Ionizing radiation induced cataracts: Recent biological and mechanistic developments and perspectives for future research.

PubMed

Ainsbury, Elizabeth A; Barnard, Stephen; Bright, Scott; Dalke, Claudia; Jarrin, Miguel; Kunze, Sarah; Tanner, Rick; Dynlacht, Joseph R; Quinlan, Roy A; Graw, Jochen; Kadhim, Munira; Hamada, Nobuyuki

The lens of the eye has long been considered as a radiosensitive tissue, but recent research has suggested that the radiosensitivity is even greater than previously thought. The 2012 recommendation of the International Commission on Radiological Protection (ICRP) to substantially reduce the annual occupational equivalent dose limit for the ocular lens has now been adopted in the European Union and is under consideration around the rest of the world. However, ICRP clearly states that the recommendations are chiefly based on epidemiological evidence because there are a very small number of studies that provide explicit biological, mechanistic evidence at doses <2Gy. This paper aims to present a review of recently published information on the biological and mechanistic aspects of cataracts induced by exposure to ionizing radiation (IR). The data were compiled by assessing the pertinent literature in several distinct areas which contribute to the understanding of IR induced cataracts, information regarding lens biology and general processes of cataractogenesis. Results from cellular and tissue level studies and animal models, and relevant human studies, were examined. The main focus was the biological effects of low linear energy transfer IR, but dosimetry issues and a number of other confounding factors were also considered. The results of this review clearly highlight a number of gaps in current knowledge. Overall, while there have been a number of recent advances in understanding, it remains unknown exactly how IR exposure contributes to opacification. A fuller understanding of how exposure to relatively low doses of IR promotes induction and/or progression of IR-induced cataracts will have important implications for prevention and treatment of this disease, as well as for the field of radiation protection. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

High lenticular tolerance to ultraviolet radiation-B by pigmented guinea-pig; application of a safety limit strategy for UVR-induced cataract.

PubMed

Mody, Vino C; Kakar, Manoj; Söderberg, Per G; Löfgren, Stefan

2012-05-01

The purpose of this study was to determine a threshold measure, maximum tolerable dose (MTD), for avoidance of UVR-B-induced cataract in the pigmented guinea-pig. Thirty pupil-dilated anesthetized young female guinea-pigs, divided into five equal groups, received between 0 and 84.9 kJ/m(2) unilateral UVR-B. Lens extraction and in vitro lens photography occurred 24 hr after exposure. Measurement of intensity of lens light scattering served as quantifying tool for the degree of cataract. Data analysis included regression, using a second order polynomial model. The applied MTD concept was based on the UVR-B dose-response curve obtained for the pigmented guinea-pig. A smaller number of pigmented guinea-pigs, pigmented rats and albino rats underwent morphometric analysis of the anterior segment geometry. All eyes exposed to UVR-B developed cataract in the anterior subcapsular region. MTD for avoidance of UVR-B-induced cataract was 69.0 kJ/m(2) in the pigmented guinea-pig. Iris was considerably thicker in the guinea-pig than in the rats. Lens blockage by the dilated iris was lowest in the guinea-pig. Maximum tolerable dose for avoidance of UVR-B-induced cataract in the pigmented guinea-pig was 69.0 kJ/m(2), over 10-fold higher than the threshold 5 kJ/m(2) obtained by Pitts et al. in the pigmented rabbit. Maximum tolerable dose is an appropriate method for estimation of toxicity for UVR-B-induced cataract in the guinea-pig. The pigmented guinea-pig is significantly less sensitive to UVR-B exposure than the pigmented rabbit and pigmented rat. © 2010 The Authors. Journal compilation © 2010 Acta Ophthalmol.

Fitness costs of increased cataract frequency and cumulative radiation dose in natural mammalian populations from Chernobyl.

PubMed

Lehmann, Philipp; Boratyński, Zbyszek; Mappes, Tapio; Mousseau, Timothy A; Møller, Anders P

2016-01-27

A cataract is a clouding of the lens that reduces light transmission to the retina, and it decreases the visual acuity of the bearer. The prevalence of cataracts in natural populations of mammals, and their potential ecological significance, is poorly known. Cataracts have been reported to arise from high levels of oxidative stress and a major cause of oxidative stress is ionizing radiation. We investigated whether elevated frequencies of cataracts are found in eyes of bank voles Myodes glareolus collected from natural populations in areas with varying levels of background radiation in Chernobyl. We found high frequencies of cataracts in voles collected from different areas in Chernobyl. The frequency of cataracts was positively correlated with age, and in females also with the accumulated radiation dose. Furthermore, the number of offspring in female voles was negatively correlated with cataract severity. The results suggest that cataracts primarily develop as a function of ionizing background radiation, most likely as a plastic response to high levels of oxidative stress. It is therefore possible that the elevated levels of background radiation in Chernobyl affect the ecology and fitness of local mammals both directly through, for instance, reduced fertility and indirectly, through increased cataractogenesis.

Historical Study of Radiation Exposures and the Incidence of Cataracts in Astronauts

NASA Technical Reports Server (NTRS)

Cucinotta, F. A.; Manuel, F. K.; Iszard, G.; Feiveson, A.; Peterson, L. E.; Hardy, D.; Marak, L.; Tung, W.; Wear, M.; Chylack, L. T., Jr.

2004-01-01

For over 35 years, astronauts in low Earth orbit or on missions to the moon have been exposed to space radiation comprised of high-energy protons, heavy ions, and secondary neutrons. We reviewed the radiation exposures received by astronauts in space and on Earth, and presented results from the first epidemiological study of cataract incidence in the astronauts. Our data suggested an increased risk for cataracts from space radiation exposures. Using parametric survival analysis and the maximum likelihood method, we estimated the dose-response and age distribution for cataract incidence in astronauts by space radiation. Considering the high-LET dose contributions on specific space missions as well as data from animal studies with neutrons and heavy ions, suggested a linear response with no dose-threshold for cataracts. However, there are unanswered questions related to the importance and the definition of clinically significant cataracts commonly used in radiation protection, especially in light of epidemiological data suggesting that the probability that sub-clinical cataracts will progress is highly dependent on the age at which cataracts appear. We briefly describe a new study that will address the measurement of cataract progression-rates in astronauts and a ground-based comparison group.

Historical Study of Radiation Exposures and the Incidence of Cataracts in Astronauts

NASA Technical Reports Server (NTRS)

Cucinotta, F. A.; Manuel, F. K.; Iszard, G.; Feiveson, A.; Peterson, L. E.; Hardy, D.; Marak, L.; Tung, W.; Wear, M.; Chylack, L. T., Jr.

2004-01-01

For over 35 years, astronauts in low Earth orbit or on missions to the moon have been exposed to space radiation comprised of high-energy protons, heavy ions, and secondary neutrons. We reviewed the radiation exposures received by astronauts in space and on Earth, and presented results from the first epidemiological study of cataract incidence in the astronauts. Our data suggested an increased risk for cataracts from space radiation exposures*. Using parametric survival analysis and the maximum likelihood method, we estimated the dose-response and age distribution for cataract incidence in astronauts by space radiation. Considering the high-LET dose contributions on specific space missions as well as data from animal studies with neutrons and heavy ions, suggested a linear response with no dose-threshold for cataracts. However, there are unanswered questions related to the importance and the definition of "clinically significant" cataracts commonly used in radiation protection, especially in light of epidemiological data suggesting that the probability that "sub-clinical" cataracts will progress is highly dependent on the age at which cataracts appear. We briefly describe a new study that will address the measurement of cataract progression-rates in astronauts and a ground-based comparison group.

Helium-ion-induced human cataractogenesis

NASA Technical Reports Server (NTRS)

Blakely, E. A.; Daftari, I. K.; Meecham, W. J.; Alonso, L. C.; Collier, J. M.; Kroll, S. M.; Gillette, E. L.; Lee, A. C.; Lett, J. T.; Cox, A. B.

1994-01-01

Retrospective and ongoing analyses of clinical records from 347 primary intraocular melanoman patients treated with helium ions at Lawrence Berkeley Laboratory (LBL) will allow examination of the exposure-response data for human cataract; which is a complication of the therapy from incidental exposure of the lens. Direct particle beam traversal of at least a portion of the lens usually is unavoidable in treatment of posterior intraocular tumors. The precise treatment planned for each patient permits quantitative assessment of the lenticular dose and its radiation quality. We are reporting our preliminary results on the development of helium-ion-induced lens opacifications and cataracts in 54 of these patients who had 10% or less of their lens in the treatment field. We believe these studies will be relevant to estimating the human risk for cataract in space flight.

Ultraviolet radiation-induced cataract in mice: the effect of age and the potential biochemical mechanism.

PubMed

Zhang, Jie; Yan, Hong; Löfgren, Stefan; Tian, Xiaoli; Lou, Marjorie F

2012-10-19

To study the effect of age on the morphologic and biochemical alterations induced by in vivo exposure of ultraviolet radiation (UV). Young and old C57BL/6 mice were exposed to broadband UVB+UVA and euthanized after 2 days. Another batch of UV-exposed young mice was monitored for changes after 1, 2, 4, and 8 days. Age-matched nonexposed mice served as controls. Lens changes were documented in vivo by slit-lamp biomicroscopy and dark field microscopy photographs ex vivo. Lens homogenates were analyzed for glutathione (GSH) level, and the activities of thioredoxin (Trx), thioltransferase (TTase), and glyceraldehyde-3-phosphate dehydrogenase (G3PD). Glutathionylated lens proteins (PSSGs) were detected by immunoblotting using GSH antibody. Western blot analysis was also done for the expression levels of TTase and Trx. Both age groups developed epithelial and superficial anterior subcapsular cataract at 2 days postexposure. The lens GSH level and G3PD activity were decreased, and PSSGs were elevated in both age groups, but more prominent in the older mice. TTase and Trx activity and protein expression were elevated only in the young mice. Interestingly, lens TTase and Trx in the young mice showed a transient increase, peaking at 2 days after UV exposure and returning to baseline at day 8, corroborated by lens transparency. The lenses of old mice were more susceptible to UV radiation-induced cataract. The upregulated TTase and Trx likely provided oxidation damage repair in the young mice.

Radiation-Induced Noncancer Risks in Interventional Cardiology: Optimisation of Procedures and Staff and Patient Dose Reduction

PubMed Central

Khairuddin Md Yusof, Ahmad

2013-01-01

Concerns about ionizing radiation during interventional cardiology have been increased in recent years as a result of rapid growth in interventional procedure volumes and the high radiation doses associated with some procedures. Noncancer radiation risks to cardiologists and medical staff in terms of radiation-induced cataracts and skin injuries for patients appear clear potential consequences of interventional cardiology procedures, while radiation-induced potential risk of developing cardiovascular effects remains less clear. This paper provides an overview of the evidence-based reviews of concerns about noncancer risks of radiation exposure in interventional cardiology. Strategies commonly undertaken to reduce radiation doses to both medical staff and patients during interventional cardiology procedures are discussed; optimisation of interventional cardiology procedures is highlighted. PMID:24027768

Cosmic Radiation and Cataracts in Airline Pilots

NASA Astrophysics Data System (ADS)

Rafnsson, V.; Olafsdottir, E.; Hrafnkelsson, J.; de Angelis, G.; Sasaki, H.; Arnarson, A.; Jonasson, F.

Nuclear cataracts have been associated with ionising radiation exposure in previous studies. A population based case-control study on airline pilots has been performed to investigate whether employment as a commercial pilot and consequent exposure to cosmic radiation were associated to lens opacification, when adjusted for known risk factors for cataracts. Cases of opacification of the ocular lens were found in surveys among pilots and a random sample of the Icelandic population. Altogether 445 male subjects underwent a detailed eye examination and answered a questionnaire. Information from the airline company on the 79 pilots employment time, annual hours flown per aircraft type, the timetables and the flight profiles made calculation of individual cumulated radiation dose (mSv) possible. Lens opacification were classified and graded according to WHO simplified cataracts grading system using slit lamp. The odds ratio from logistic regression of nuclear cataracts risk among cases and controls was 3.02 (95% CI 1.44 to 6.35) for pilots compared with non-pilots, adjusted for age, smoking and sunbathing habits, whereas that of cortical cataracts risk among cases and controls was lower than unity (non significant) for pilots compared with non-pilots in a logistic regression analysis adjusted for same factors. Length of employment as a pilot and cumulated radiation dose (mSv) were significantly related to the risk of nuclear cataracts. So the association between radiation exposure of pilots and the risk of nuclear cataracts, adjusted for age, smoking and sunbathing habits, indicates that cosmic radiation may be cause of nuclear cataract among commercial pilots.

Space radiation and cataracts in astronauts.

PubMed

Cucinotta, F A; Manuel, F K; Jones, J; Iszard, G; Murrey, J; Djojonegro, B; Wear, M

2001-11-01

For over 30 years, astronauts in Earth orbit or on missions to the moon have been exposed to space radiation comprised of high-energy protons and heavy ions and secondary particles produced in collisions with spacecraft and tissue. Large uncertainties exist in the projection of risks of late effects from space radiation such as cancer and cataracts due to the paucity [corrected] of epidemiological data. Here we present epidemiological [corrected] data linking an increased risk of cataracts for astronauts with higher lens doses (>8 mSv) of space radiation relative to other astronauts with lower lens doses (<8 mSv). Our study uses historical data for cataract incidence in the 295 astronauts participating in NASA's Longitudinal Study of Astronaut Health (LSAH) and individual occupational radiation exposure data. These results, while preliminary because of the use of subjective scoring methods, suggest that relatively low doses of space radiation may predispose crew to [corrected] an increased incidence and early appearance of cataracts.

Space radiation and cataracts in astronauts

NASA Technical Reports Server (NTRS)

Cucinotta, F. A.; Manuel, F. K.; Jones, J.; Iszard, G.; Murrey, J.; Djojonegro, B.; Wear, M.

2001-01-01

For over 30 years, astronauts in Earth orbit or on missions to the moon have been exposed to space radiation comprised of high-energy protons and heavy ions and secondary particles produced in collisions with spacecraft and tissue. Large uncertainties exist in the projection of risks of late effects from space radiation such as cancer and cataracts due to the paucity [corrected] of epidemiological data. Here we present epidemiological [corrected] data linking an increased risk of cataracts for astronauts with higher lens doses (>8 mSv) of space radiation relative to other astronauts with lower lens doses (<8 mSv). Our study uses historical data for cataract incidence in the 295 astronauts participating in NASA's Longitudinal Study of Astronaut Health (LSAH) and individual occupational radiation exposure data. These results, while preliminary because of the use of subjective scoring methods, suggest that relatively low doses of space radiation may predispose crew to [corrected] an increased incidence and early appearance of cataracts.

Eye lens radiation exposure and repeated head CT scans: A problem to keep in mind.

PubMed

Michel, Morgane; Jacob, Sophie; Roger, Gilles; Pelosse, Béatrice; Laurier, Dominique; Le Pointe, Hubert Ducou; Bernier, Marie-Odile

2012-08-01

The deterministic character of radiation-induced cataract is being called into question, raising the possibility of a risk in patients, especially children, exposed to ionizing radiation in case of repeated head CT-scans. This study aims to estimate the eye lens doses of a pediatric population exposed to repeated head CTs and to assess the feasibility of an epidemiological study. Children treated for a cholesteatoma, who had had at least one CT-scan of the middle ear before their tenth birthday, were included. Radiation exposure has been assessed from medical records and telephone interviews. Out of the 39 subjects contacted, 32 accepted to participate. A total of 76 CT-scans were retrieved from medical records. At the time of the interview (mean age: 16 years), the mean number of CT per child was 3. Cumulative mean effective and eye lens doses were 1.7mSv and 168mGy, respectively. A relatively high lens radiation dose was observed in children exposed to repeated CT-scans. Due to that exposure and despite the difficulties met when trying to reach patients' families, a large scale epidemiological study should be performed in order to assess the risk of radiation-induced cataracts associated with repeated head CT. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Eye lens radiation exposure to interventional cardiologists: a retrospective assessment of cumulative doses.

PubMed

Jacob, Sophie; Donadille, Laurent; Maccia, Carlo; Bar, Olivier; Boveda, Serge; Laurier, Dominique; Bernier, Marie-Odile

2013-03-01

Radiation dose to the eye lens is a crucial issue for interventional cardiologists (ICs) who are exposed during the procedures they perform. This paper presents a retrospective assessment of the cumulative eye lens doses of ICs enrolled in the O'CLOC study for Occupational Cataracts and Lens Opacities in interventional Cardiology. Information on the workload in the catheterisation laboratory, radiation protection equipment, eye lens dose per procedure and dose reduction factors associated with eye-protective equipment were considered. For the 129 ICs at an average age of 51 who had worked for an average period of 22 years, the estimated cumulative eye lens dose ranged from 25 mSv to more than 1600 mSv; the mean ± SD was 423 ± 359 mSv. After several years of practice, without eye protection, ICs may exceed the new ICRP lifetime eye dose threshold of 500 mSv and be at high risk of developing early radiation-induced cataracts. Radiation protection equipment can reduce these doses and should be used routinely.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hall, Matthew D.; Schultheiss, Timothy E., E-mail: schultheiss@coh.org; Smith, David D.

Purpose/Objective(s): To perform a meta-regression on published data and to model the 5-year probability of cataract development after hematopoietic stem cell transplantation (HSCT) with and without total body irradiation (TBI). Methods and Materials: Eligible studies reporting cataract incidence after HSCT with TBI were identified by a PubMed search. Seventeen publications provided complete information on radiation dose schedule, fractionation, dose rate, and actuarial cataract incidence. Chemotherapy-only regimens were included as zero radiation dose regimens. Multivariate meta-regression with a weighted generalized linear model was used to model the 5-year cataract incidence and contributory factors. Results: Data from 1386 patients in 21 seriesmore » were included for analysis. TBI was administered to a total dose of 0 to 15.75 Gy with single or fractionated schedules with a dose rate of 0.04 to 0.16 Gy/min. Factors significantly associated with 5-year cataract incidence were dose, dose times dose per fraction (D•dpf), pediatric versus adult status, and the absence of an ophthalmologist as an author. Dose rate, graft versus host disease, steroid use, hyperfractionation, and number of fractions were not significant. Five-fold internal cross-validation showed a model validity of 83% ± 8%. Regression diagnostics showed no evidence of lack-of-fit and no patterns in the studentized residuals. The α/β ratio from the linear quadratic model, estimated as the ratio of the coefficients for dose and D•dpf, was 0.76 Gy (95% confidence interval [CI], 0.05-1.55). The odds ratio for pediatric patients was 2.8 (95% CI, 1.7-4.6) relative to adults. Conclusions: Dose, D•dpf, pediatric status, and regimented follow-up care by an ophthalmologist were predictive of 5-year cataract incidence after HSCT. The low α/β ratio indicates the importance of fractionation in reducing cataracts. Dose rate effects have been observed in single institution studies but not in the combined data analyzed here. Although data were limited to articles with 5-year actuarial estimates, the development of radiation-induced cataracts extends beyond this time.« less

Use of non-subjective analysis of lens transparency in experimental radiation cataract research

NASA Technical Reports Server (NTRS)

Worgul, B. V.; Medvedovsky, C.; Wu, B.

1995-01-01

Historically the major impediment to radiation cataract follow-up has been the necessarily subjective nature of assessing the degree of lens transparency. This has spurred the development of instruments which produce video images amenable to digital analysis. One such system, the Zeiss Scheimpflug slit lamp measuring system (SLC), was incorporated into our ongoing studies of radiation cataractogenesis. It was found that the Zeiss SLC measuring system has high resolution and permits the acquisition of reproducible images of the anterior segment of the eye. Our results, based on about 650 images of lenses followed over a period of 91 weeks of radiation cataract development, showed that the changes in the light scatter of the lens correlated well with conventional assessment of radiation cataracts with the added advantages of objectivity, permanent and transportable records and linearity as cataracts become more severe. This continuous data acquisition, commencing with cataract onset, can proceed through more advanced stages. The SLC exhibits much greater sensitivity reflected in a continuously progressive severity thereby avoiding the artifactual plateaus in staging which occur using conventional scoring methods.

Potential pre-cataractous markers induced by low-dose radiation effects in cultured human lens cells

NASA Astrophysics Data System (ADS)

Blakely, E.; McNamara, M.; Bjornstad, K.; Chang, P.

The human lens is one of the most radiosensitive organs of the body. Cataract, the opacification of the lens, is a late-appearing response to radiation damage. Recent evidence indicates that exposure to relatively low doses of space radiation are associated with an increased incidence and early appearance of human cataracts (Cucinotta et al., Radiat. Res. 156:460-466, 2001). Basic research in this area is needed to integrate the early responses of various late-responding tissues into our understanding and estimation of radiation risk for space travel. In addition, these studies may contribute to the development of countermeasures for the early lenticular changes, in order to prevent the late sequelae. Radiation damage to the lens is not life threatening but, if severe, can affect vision unless surgically corrected with synthetic lens replacement. The lens, however, may be a sensitive detector of radiation effects for other cells of ectodermal origin in the body for which there are not currently clear endpoints of low-dose radiation effects. We have investigated the dose-dependent expression of several radiation-responsive endpoints using our in vitro model of differentiating human lens epithelial cells (Blakely et al., Investigative Ophthalmology &Visual Sciences, 41(12):3898-3907, 2000). We have investigated radiation effects on several gene families that include, or relate to, DNA damage, cytokines, cell-cycle regulators, cell adhesion molecules, cell cytoskeletal function and apoptotic cell death. In this paper we will summarize some of our dose-dependent data from several radiation types, and describe the model of molecular and cellular events that we believe may be associated with precataractous events in the human lens after radiation exposure. This work was supported by NASA Grant #T-965W.

Cataract frequency and subtypes involved in workers assessed for their solar radiation exposure: a systematic review.

PubMed

Modenese, Alberto; Gobba, Fabriziomaria

2018-04-16

Cataract is currently the primary cause of blindness worldwide, and one of its main risk factors is solar ultraviolet radiation exposure. According to the localization of lens opacities, three main subtypes of cataract are recognized: nuclear, cortical and posterior subcapsular cataract. One of the main determinants of individual long-term solar radiation exposure is outdoor work. We systematically reviewed scientific literature from the last 20 years to update the recent development of research on the risk of cataract in outdoor workers and on the specific subtypes involved, also investigating the methods applied to evaluate the occupational risk. A total of 15 studies were included in the review, of which 12 showed a positive association. The studies confirm the relationship of long-term occupational solar radiation exposure with cortical cataract and give new support for nuclear cataract, although no substantial new data were available to support a relation with the posterior subcapsular subtype. In most of the studies, the exposure assessment was not adequate to support a representative evaluation of the ocular risk; however, outdoor work is clearly a relevant risk factor for cataract. Further research providing a better evaluation of the relation between solar radiation exposure levels and lens damage in workers is needed and aimed to establish adequate occupational exposure limits and better preventive measures, studying also their effectiveness. © 2018 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Understanding Cataract Risk in Aerospace Flight Crew And Review of Mechanisms of Cataract Formation

NASA Technical Reports Server (NTRS)

Jones, Jeffrey A.; McCarten, M.; Manuel, K.; Djojonegoro, B.; Murray, J.; Cucinotta, F.; Feiversen, A.; Wear, M.

2006-01-01

Induction of cataracts by occupational exposure in flight crew has been an important topic of interest in aerospace medicine in the past five years, in association with numerous reports of flight-associated disease incidences. Due to numerous confounding variables, it has been difficult to determine if there is increased cataract risk directly caused by interaction with the flight environment, specifically associated with added radiation exposure during flight. Military aviator records from the United States Air Force (USAF) and Navy (USN) and US astronauts at the National Aeronautics and Space Administration (NASA)/Lyndon B. Johnson Space Center (JSC) were evaluated for the presence, location and age of diagnosis of cataracts. Military aviators were found to have a statistically significant younger average age of onset of their cataracts compared with astronauts, however the incidence density of cataracts was found to be statistically higher in astronauts than in military aviators. USAF and USN aviator s cataracts were most commonly located in the posterior subcapsular region of the lens while astronauts cataracts were most likely to originate generally in the cortical zone. A prospective clinical trial which controls for confounding variables in examination technique, cataract classification, diet, exposure, and pharmacological intervention is needed to determine what percentage of the risk for cataracts are due to radiation, and how to best develop countermeasures to protect flight crews from radiation bioeffects in the future.

Radiation dose and cataract surgery incidence in atomic bomb survivors, 1986-2005.

PubMed

Neriishi, Kazuo; Nakashima, Eiji; Akahoshi, Masazumi; Hida, Ayumi; Grant, Eric J; Masunari, Naomi; Funamoto, Sachiyo; Minamoto, Atsushi; Fujiwara, Saeko; Shore, Roy E

2012-10-01

To examine the incidence of clinically important cataracts in relation to lens radiation doses between 0 and approximately 3 Gy to address risks at relatively low brief doses. Informed consent was obtained, and human subjects procedures were approved by the ethical committee at the Radiation Effects Research Foundation. Cataract surgery incidence was documented for 6066 atomic bomb survivors during 1986-2005. Sixteen risk factors for cataract, such as smoking, hypertension, and corticosteroid use, were not confounders of the radiation effect on the basis of Cox regression analysis. Radiation dose-response analyses were performed for cataract surgery incidence by using Poisson regression analysis, adjusting for demographic variables and diabetes mellitus, and results were expressed as the excess relative risk (ERR) and the excess absolute risk (EAR) (ie, measures of how much radiation multiplies [ERR] or adds to [EAR] the risk in the unexposed group). Of 6066 atomic bomb survivors, 1028 underwent a first cataract surgery during 1986-2005. The estimated threshold dose was 0.50 Gy (95% confidence interval [CI]: 0.10 Gy, 0.95 Gy) for the ERR model and 0.45 Gy (95% CI: 0.10 Gy, 1.05 Gy) for the EAR model. A linear-quadratic test for upward curvature did not show a significant quadratic effect for either the ERR or EAR model. The linear ERR model for a 70-year-old individual, exposed at age 20 years, showed a 0.32 (95% CI: 0.09, 0.53) [corrected] excess risk at 1 Gy. The ERR was highest for those who were young at exposure. These data indicate a radiation effect for vision-impairing cataracts at doses less than 1 Gy. The evidence suggests that dose standards for protection of the eye from brief radiation exposures should be 0.5 Gy or less. © RSNA, 2012.

NASA study of cataract in astronauts (NASCA). Report 1: Cross-sectional study of the relationship of exposure to space radiation and risk of lens opacity.

PubMed

Chylack, Leo T; Peterson, Leif E; Feiveson, Alan H; Wear, Mary L; Manuel, F Keith; Tung, William H; Hardy, Dale S; Marak, Lisa J; Cucinotta, Francis A

2009-07-01

The NASA Study of Cataract in Astronauts (NASCA) is a 5-year longitudinal study of the effect of space radiation exposure on the severity/progression of nuclear, cortical and posterior subcapsular (PSC) lens opacities. Here we report on baseline data that will be used over the course of the longitudinal study. Participants include 171 consenting astronauts who flew at least one mission in space and a comparison group made up of three components: (a) 53 astronauts who had not flown in space, (b) 95 military aircrew personnel, and (c) 99 non-aircrew ground-based comparison subjects. Continuous measures of nuclear, cortical and PSC lens opacities were derived from Nidek EAS 1000 digitized images. Age, demographics, general health, nutritional intake and solar ocular exposure were measured at baseline. Astronauts who flew at least one mission were matched to comparison subjects using propensity scores based on demographic characteristics and medical history stratified by gender and smoking (ever/never). The cross-sectional data for matched subjects were analyzed by fitting customized non-normal regression models to examine the effect of space radiation on each measure of opacity. The variability and median of cortical cataracts were significantly higher for exposed astronauts than for nonexposed astronauts and comparison subjects with similar ages (P=0.015). Galactic cosmic space radiation (GCR) may be linked to increased PSC area (P=0.056) and the number of PSC centers (P=0.095). Within the astronaut group, PSC size was greater in subjects with higher space radiation doses (P=0.016). No association was found between space radiation and nuclear cataracts. Cross-sectional data analysis revealed a small deleterious effect of space radiation for cortical cataracts and possibly for PSC cataracts. These results suggest increased cataract risks at smaller radiation doses than have been reported previously.

DNA damage in lens epithelium of cataract patients in vivo and ex vivo.

PubMed

Øsnes-Ringen, Oyvind; Azqueta, Amaia O; Moe, Morten C; Zetterström, Charlotta; Røger, Magnus; Nicolaissen, Bjørn; Collins, Andrew R

2013-11-01

DNA damage has been described in the human cataractous lens epithelium, and oxidative stress generated by UV radiation and endogenous metabolic processes has been suggested to play a significant role in the pathogenesis of cataract. In this study, the aim was to explore the quality and relative quantity of DNA damage in lens epithelium of cataract patients in vivo and after incubation in a cell culture system. Capsulotomy specimens were analysed, before and after 1 week of ex vivo cultivation, using the comet assay to measure DNA strand breaks, oxidized purine and pyrimidine bases and UV-induced cyclobutane pyrimidine dimers. DNA strand breaks were barely detectable, oxidized pyrimidines and pyrimidine dimers were present at low levels, whereas there was a relatively high level of oxidized purines, which further increased after cultivation. The observed levels of oxidized purines in cataractous lens epithelium may support a theory consistent with light damage and oxidative stress as mediators of molecular damage to the human lens epithelium. Damage commonly associated with UV-B irradiation was relatively low. The levels of oxidized purines increased further in a commonly used culture system. This is of interest considering the importance and versatility of ex vivo systems in studies exploring the pathogenesis of cataract. © 2012 The Authors. Acta Ophthalmologica © 2012 Acta Ophthalmologica Scandinavica Foundation.

Cosmic radiation increases the risk of nuclear cataract in airline pilots: a population-based case-control study.

PubMed

Rafnsson, Vilhjalmur; Olafsdottir, Eydis; Hrafnkelsson, Jon; Sasaki, Hiroshi; Arnarsson, Arsaell; Jonasson, Fridbert

2005-08-01

Aviation involves exposure to ionizing radiation of cosmic origin. The association between lesions of the ocular lens and ionizing radiation is well-known. To investigate whether employment as a commercial airline pilot and the resulting exposure to cosmic radiation is associated with lens opacification. This is a population-based case-control study of 445 men. Lens opacification was classified into 4 types using the World Health Organization simplified grading system. These 4 types, serving as cases, included 71 persons with nuclear cataracts, 102 with cortical lens opacification, 69 with central optical zone involvement, and 32 with posterior subcapsular lens opacification. Control subjects are those with a different type of lens opacification or without lens opacification. Exposure was assessed based on employment time as pilots, annual number of hours flown on each aircraft type, time tables, flight profiles, and individual cumulative radiation doses (in millisieverts) calculated by a software program. Odds ratios were calculated using logistic regression. The odds ratio for nuclear cataract risk among cases and controls was 3.02 (95% confidence interval, 1.44-6.35) for pilots compared with nonpilots, adjusted for age, smoking status, and sunbathing habits. The odds ratio for nuclear cataract associated with estimation of cumulative radiation dose (in millisieverts) to the age of 40 years was 1.06 (95% confidence interval, 1.02-1.10), adjusted for age, smoking status, and sunbathing habits. The association between the cosmic radiation exposure of pilots and the risk of nuclear cataracts, adjusted for age, smoking status, and sunbathing habits, indicates that cosmic radiation may be a causative factor in nuclear cataracts among commercial airline pilots.

Low dose or low dose rate ionizing radiation-induced health effect in the human.

PubMed

Tang, Feng Ru; Loganovsky, Konstantin

2018-06-05

The extensive literature review on human epidemiological studies suggests that low dose ionizing radiation (LDIR) (≤100 mSv) or low dose rate ionizing radiation (LDRIR) (<6mSv/H) exposure could induce either negative or positive health effects. These changes may depend on genetic background, age (prenatal day for embryo), sex, nature of radiation exposure, i.e., acute or chronic irradiation, radiation sources (such as atomic bomb attack, fallout from nuclear weapon test, nuclear power plant accidents, 60 Co-contaminated building, space radiation, high background radiation, medical examinations or procedures) and radionuclide components and human epidemiological experimental designs. Epidemiological and clinical studies show that LDIR or LDRIR exposure may induce cancer, congenital abnormalities, cardiovascular and cerebrovascular diseases, cognitive and other neuropsychiatric disorders, cataracts and other eye and somatic pathology (endocrine, bronchopulmonary, digestive, etc). LDIR or LDRIR exposure may also reduce mutation and cancer mortality rates. So far, the mechanisms of LDIR- or LDRIR -induced health effect are poorly understood. Further extensive studies are still needed to clarify under what circumstances, LDIR or LDRIR exposure may induce positive or negative effects, which may facilitate development of new therapeutic approaches to prevent or treat the radiation-induced human diseases or enhance radiation-induced positive health effect. Copyright © 2018 Elsevier Ltd. All rights reserved.

Drinking water supplementation with ascorbate is not protective against UVR-B-induced cataract in the guinea pig.

PubMed

Mody, Vino C; Kakar, Manoj; Elfving, Ase; Löfgren, Stefan

2008-03-01

To study if ascorbate supplementation decreases ultraviolet radiation (UVR)-induced cataract development in the guinea pig. Sixty 6-9-week-old pigmented guinea pigs received drinking water supplemented with or without 5.5 mm l-ascorbate for 4 weeks. After supplementation, 40 animals were exposed unilaterally in vivo under anaesthesia to 80 kJ/m(2) UVR-B. One day later, the animals were killed and lenses were extracted. Degree of cataract was quantified by measurement of intensity of forward lens light scattering. Lens ascorbate concentration was determined with high-performance liquid chromatography (HPLC) with UVR detection at 254 nm. Twenty animals were used as non-exposed control. Supplementation increased lens ascorbate concentration significantly. In UVR-exposed animals, mean 95% confidence intervals (CIs) for animal-averaged lens ascorbate concentration (micromol/g wet weight lens) were 0.54 +/- 0.07 (no ascorbate) and 0.83 +/- 0.05 (5.5 mm ascorbate). In non-exposed control animals, mean 95% CIs for animal-averaged lens ascorbate concentration (micromol/g wet weight lens) were 0.72 +/- 0.12 (0 mm ascorbate) and 0.90 +/- 0.15 (5.5 mm ascorbate). All non-exposed lenses were devoid of cataract. Superficial anterior cataract developed in all UVR-exposed lenses. The lens light scattering was 39.2 +/- 14.1 milli transformed equivalent diazepam concentration (m(tEDC)) without and 35.9 +/- 14.0 m(tEDC) with ascorbate supplementation. Superficial anterior cataract develops in lenses exposed to UVR-B. Ascorbate supplementation is non-toxic to both UVR-B-exposed lenses and non-exposed control lenses. Ascorbate supplementation does not reduce in vivo lens forward light scattering secondary to UVR-B exposure in the guinea pig.

Radiation and cataract.

PubMed

Rehani, Madan M; Vano, Eliseo; Ciraj-Bjelac, Olivera; Kleiman, Norman J

2011-09-01

When this paper was about to go to press, the International Commission on Radiological Protection released a statement recommending a change in the threshold dose for the eye lens and dose limits for eye for occupationally exposed persons. It is clear that the earlier published threshold for radiation cataract is no longer valid. Epidemiological studies among Chernobyl clean-up workers, A bomb survivors, astronauts, residents of contaminated buildings, radiological technicians and recent surveys of staff in interventional rooms indicate that there is an increased incidence of lens opacities at doses below 1 Gy. Nevertheless, eye lens dosimetry is at a primitive stage and needs to be developed further. Despite uncertainties concerning dose threshold and dosimetry, it is possible to significantly reduce the risk of radiation cataract through the use of appropriate eye protection. By increasing awareness among those at risk and better adoption and increased usage of protective measures, radiation cataract can become preventable despite lowering of dose limits.

Protective effects of ebselen on sodium-selenite-induced experimental cataract in rats.

PubMed

Aydemir, Orhan; Güler, Mete; Kaya, Mehmet Kaan; Deniz, Nurettin; Üstündağ, Bilal

2012-12-01

To determine whether ebselen has a protective effect or antioxidative potential in a sodium-selenite-induced experimental cataract model. Fırat University, Elazığ, Turkey. Experimental study. Twenty-one Sprague-Dawley rat pups were randomly divided into a control group, a sodium-selenite-induced-cataract group, and an ebselen-treated group; each group contained 7 rat pups. Rats in the control group received dimethyl sulfoxide (DMSO) intraperitoneally only and rats in the sodium-selenite-induced-cataract group received 30 nmol/g body weight sodium selenite subcutaneously and DMSO intraperitoneally 10 days postpartum. Rats in the ebselen group received 30 nmol/g body weight sodium selenite subcutaneously 10 days postpartum and were treated with 5 mg/kg body weight ebselen once a day for 4 consecutive days. Cataract development was assessed weekly for 3 weeks by slitlamp examination and graded using a scale. Reduced glutathione (GSH), total nitrite, and malondialdehyde (MDA) levels in lens supernatants were measured at the end of 3 weeks. In the control group, all lenses were clear. In the ebselen-treated group, the mean cataract stage was significantly lower than in the sodium-selenite-induced-cataract group (P = .022). The GSH levels were significantly lower in the sodium-selenite-induced-cataract group than in the control and ebselen groups (P < .001). The MDA levels were lower in the ebselen group than in the sodium-selenite-induced-cataract group (P < .001). The mean total nitrite level was significantly lower in the sodium-selenite-induced-cataract group than in the ebselen group (P = .001). Ebselen had a protective effect on cataract development in a sodium-selenite-induced experimental model. The protective effect of ebselen appears to be due to inhibition of oxidative stress. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Cataract Avoidance With Proton Therapy in Ocular Melanomas.

PubMed

Thariat, Juliette; Jacob, Sophie; Caujolle, Jean-Pierre; Maschi, Celia; Baillif, Stéphanie; Angellier, Gaelle; Mathis, Thibaud; Rosier, Laurence; Carnicer, Adela; Hérault, Joel; Salleron, Julia

2017-10-01

The lens is a radiosensitive organ. Any dose of cephalic irradiation can give rise to radiation-induced cataracts. Contrary to other forms of radiotherapy, proton therapy (PT) can spare all or part of the lens due to accurate dose deposition. We investigated whether a lens-sparing approach was relevant to avoid cataracts in uveal melanoma patients. Patients were referred for PT from onco-ophthalmologists of private and academic institutions. Patients without preexisting cataracts or implants were entered in a prospective database. Dose thresholds responsible for cataracts were investigated in volumes of lens or lens periphery. Lens opacifications and de novo vision-impairing cataracts (VICs) had biannual follow up by ophthalmologists blinded to lens dose. Correlations between dose-volume relationships and VICs were assessed using univariate/multivariate regressions. Between 1991 and 2015, 1696 uveal melanoma patients were consecutively treated with PT. After a median follow up of 48 months, 14.4% and 8.7% of patients had cataracts and VIC within median times of 19 and 28 months, respectively. Median values of mean lens and lens periphery doses were 1.1 (radiobiologically effective [RBE] dose in photon-equivalent grays [GyRBE]) and 6.5 GyRBE, respectively. The lens received no dose in 25% of the patients. At an irradiated lens volume of ≤5%, there was no significantly increased risk for VIC below a dose of 10 GyRBE. A lens-sparing approach is feasible and results not only in reduced need for cataract surgery but also in better fundus-based tumor control. Reassessment of radioprotection rules for lens dose thresholds may follow.

Emerging issues in radiogenic cataracts and cardiovascular disease.

PubMed

Hamada, Nobuyuki; Fujimichi, Yuki; Iwasaki, Toshiyasu; Fujii, Noriko; Furuhashi, Masato; Kubo, Eri; Minamino, Tohru; Nomura, Takaharu; Sato, Hitoshi

2014-09-01

In 2011, the International Commission on Radiological Protection issued a statement on tissue reactions (formerly termed non-stochastic or deterministic effects) to recommend lowering the threshold for cataracts and the occupational equivalent dose limit for the crystalline lens of the eye. Furthermore, this statement was the first to list circulatory disease (cardiovascular and cerebrovascular disease) as a health hazard of radiation exposure and to assign its threshold for the heart and brain. These changes have stimulated various discussions and may have impacts on some radiation workers, such as those in the medical sector. This paper considers emerging issues associated with cataracts and cardiovascular disease. For cataracts, topics dealt with herein include (i) the progressive nature, stochastic nature, target cells and trigger events of lens opacification, (ii) roles of lens protein denaturation, oxidative stress, calcium ions, tumor suppressors and DNA repair factors in cataractogenesis, (iii) dose rate effect, radiation weighting factor, and classification systems for cataracts, and (iv) estimation of the lens dose in clinical settings. Topics for cardiovascular disease include experimental animal models, relevant surrogate markers, latency period, target tissues, and roles of inflammation and cellular senescence. Future research needs are also discussed. © The Author 2014. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

A Class I (Senofilcon A) Soft Contact Lens Prevents UVB-Induced Ocular Effects, Including Cataract, in the Rabbit In Vivo

PubMed Central

Lin, Li-Ren; Leverenz, Victor R.; Dang, Loan

2011-01-01

Purpose. UVB radiation from sunlight is known to be a risk factor for human cataract. The purpose in this study was to investigate the ability of a class I UV-blocking soft contact lens to protect against UVB-induced effects on the ocular tissues of the rabbit in vivo. Methods. Eyes of rabbits were exposed to UVB light for 30 minutes (270–360 nm, peak at 310 nm, 1.7 mW/cm2 on the cornea). Eyes were irradiated in the presence of either a UV-blocking senofilcon A contact lens, a minimally UV-blocking lotrafilcon A contact lens, or no contact lens at all. Effects on the cornea and lens were evaluated at various times after exposure. Results. Eyes irradiated with no contact lens protection showed corneal epithelial cell loss plus lens epithelial cell swelling, vacuole formation, and DNA single-strand breaks, as well as lens anterior subcapsular opacification. The senofilcon A lens protected nearly completely against the UVB-induced effects, whereas the lotrafilcon A lens showed no protection. Conclusions. The results indicate that use of a senofilcon A contact lens is beneficial in protecting ocular tissues of the rabbit against the harmful effects of UVB light, including photokeratitis and cataract. PMID:21421866

A class I (Senofilcon A) soft contact lens prevents UVB-induced ocular effects, including cataract, in the rabbit in vivo.

PubMed

Giblin, Frank J; Lin, Li-Ren; Leverenz, Victor R; Dang, Loan

2011-06-01

UVB radiation from sunlight is known to be a risk factor for human cataract. The purpose in this study was to investigate the ability of a class I UV-blocking soft contact lens to protect against UVB-induced effects on the ocular tissues of the rabbit in vivo. Eyes of rabbits were exposed to UVB light for 30 minutes (270-360 nm, peak at 310 nm, 1.7 mW/cm(2) on the cornea). Eyes were irradiated in the presence of either a UV-blocking senofilcon A contact lens, a minimally UV-blocking lotrafilcon A contact lens, or no contact lens at all. Effects on the cornea and lens were evaluated at various times after exposure. Eyes irradiated with no contact lens protection showed corneal epithelial cell loss plus lens epithelial cell swelling, vacuole formation, and DNA single-strand breaks, as well as lens anterior subcapsular opacification. The senofilcon A lens protected nearly completely against the UVB-induced effects, whereas the lotrafilcon A lens showed no protection. The results indicate that use of a senofilcon A contact lens is beneficial in protecting ocular tissues of the rabbit against the harmful effects of UVB light, including photokeratitis and cataract.

The Risk of Cataract among Survivors of Childhood and Adolescent Cancer: A Report from the Childhood Cancer Survivor Study

PubMed Central

Chodick, Gabriel; Sigurdson, Alice J.; Kleinerman, Ruth A.; Sklar, Charles A.; Leisenring, Wendy; Mertens, Ann C.; Stovall, Marilyn; Smith, Susan A.; Weathers, Rita E.; Veiga, Lene H. S.; Robison, Leslie L.; Inskip, Peter D.

2016-01-01

With therapeutic successes and improved survival after a cancer diagnosis in childhood, increasing numbers of cancer survivors are at risk of subsequent treatment-related morbidities, including cataracts. While it is well known that the lens of the eye is one of the most radiosensitive tissues in the human body, the risks associated with radiation doses less than 2 Gy are less understood, as are the long- and short-term cataract risks from exposure to ionizing radiation at a young age. In this study, we followed 13,902 five-year survivors of childhood cancer in the Childhood Cancer Survivor Study cohort an average of 21.4 years from the date of first cancer diagnosis. For patients receiving radiotherapy, lens dose (mean: 2.2 Gy; range: 0–66 Gy) was estimated based on radiotherapy records. We used unconditional multivariable logistic regression models to evaluate prevalence of self-reported cataract in relationship to cumulative radiation dose both at five years after the initial cancer diagnosis and at the end of follow-up. We modeled the radiation effect in terms of the excess odds ratio (EOR) per Gy. We also analyzed cataract incidence starting from five years after initial cancer diagnosis to the end of follow-up using Cox regression. A total of 483 (3.5%) cataract cases were identified, including 200 (1.4%) diagnosed during the first five years of follow-up. In a multivariable logistic regression model, cataract prevalence at the end of follow-up was positively associated with lens dose in a manner consistent with a linear dose-response relationship (EOR per Gy = 0.92; 95% CI: 0.65–1.20). The odds ratio for doses between 0.5 and 1.5 Gy was elevated significantly relative to doses <0.5 Gy (OR = 2.2; 95% CI: 1.3–3.7). The results from this study indicate a strong association between ocular exposure to ionizing radiation and long-term risk of pre-senile cataract. The risk of cataract increased with increasing exposure, beginning at lens doses as low as 0.5 Gy. Our findings are in agreement with a growing body of evidence of an elevated risk for lens opacities in populations exposed to doses of ionizing radiation below the previously suggested threshold level of 2 Gy. PMID:27023263

Tryptophan Cluster Protects Human γD-Crystallin from Ultraviolet Radiation-Induced Photoaggregation In Vitro

PubMed Central

Schafheimer, Nathaniel; King, Jonathan

2013-01-01

Exposure to ultraviolet radiation (UVR) is a significant risk factor for age-related cataract, a disease of the human lens and the most prevalent cause of blindness in the world. Cataract pathology involves protein misfolding and aggregation of the primary proteins of the lens, the crystallins. Human γD-crystallin (HγD-Crys) is a major γ-crystallin in the nucleus of the human lens. We report here analysis of UVR-induced damage to HγD-Crys in vitro. Irradiation of solutions of recombinant HγD-Crys with UVA/UVB light produced a rise in solution turbidity due to polymerization of the monomeric crystallins into higher molecular weight aggregates. A significant fraction of this polymerized protein was covalently linked. Photoaggregation of HγD-Crys required oxygen and its rate was protein concentration and UVR dose dependent. To investigate the potential roles of individual tryptophan residues in photoaggregation, triple W:F mutants of HγD-Crys were irradiated. Surprisingly, despite reducing UVR absorbing capacity, multiple W:F HγD-Crys mutant proteins photoaggregated more quickly and extensively than wild type. The results reported here are consistent with previous studies that postulated that an energy transfer mechanism between the highly conserved pairs of tryptophan residues in HγD-Crys could be protective against UVR-induced photodamage. PMID:23683003

Countermeasures for space radiation induced adverse biologic effects

NASA Astrophysics Data System (ADS)

Kennedy, A. R.; Wan, X. S.

2011-11-01

Radiation exposure in space is expected to increase the risk of cancer and other adverse biological effects in astronauts. The types of space radiation of particular concern for astronaut health are protons and heavy ions known as high atomic number and high energy (HZE) particles. Recent studies have indicated that carcinogenesis induced by protons and HZE particles may be modifiable. We have been evaluating the effects of proton and HZE particle radiation in cultured human cells and animals for nearly a decade. Our results indicate that exposure to proton and HZE particle radiation increases oxidative stress, cytotoxicity, cataract development and malignant transformation in in vivo and/or in vitro experimental systems. We have also shown that these adverse biological effects can be prevented, at least partially, by treatment with antioxidants and some dietary supplements that are readily available and have favorable safety profiles. Some of the antioxidants and dietary supplements are effective in preventing radiation induced malignant transformation in vitro even when applied several days after the radiation exposure. Our recent progress is reviewed and discussed in the context of the relevant literature.

Germ-line and somatic EPHA2 coding variants in lens aging and cataract.

PubMed

Bennett, Thomas M; M'Hamdi, Oussama; Hejtmancik, J Fielding; Shiels, Alan

2017-01-01

Rare germ-line mutations in the coding regions of the human EPHA2 gene (EPHA2) have been associated with inherited forms of pediatric cataract, whereas, frequent, non-coding, single nucleotide variants (SNVs) have been associated with age-related cataract. Here we sought to determine if germ-line EPHA2 coding SNVs were associated with age-related cataract in a case-control DNA panel (> 50 years) and if somatic EPHA2 coding SNVs were associated with lens aging and/or cataract in a post-mortem lens DNA panel (> 48 years). Micro-fluidic PCR amplification followed by targeted amplicon (exon) next-generation (deep) sequencing of EPHA2 (17-exons) afforded high read-depth coverage (1000x) for > 82% of reads in the cataract case-control panel (161 cases, 64 controls) and > 70% of reads in the post-mortem lens panel (35 clear lens pairs, 22 cataract lens pairs). Novel and reference (known) missense SNVs in EPHA2 that were predicted in silico to be functionally damaging were found in both cases and controls from the age-related cataract panel at variant allele frequencies (VAFs) consistent with germ-line transmission (VAF > 20%). Similarly, both novel and reference missense SNVs in EPHA2 were found in the post-mortem lens panel at VAFs consistent with a somatic origin (VAF > 3%). The majority of SNVs found in the cataract case-control panel and post-mortem lens panel were transitions and many occurred at di-pyrimidine sites that are susceptible to ultraviolet (UV) radiation induced mutation. These data suggest that novel germ-line (blood) and somatic (lens) coding SNVs in EPHA2 that are predicted to be functionally deleterious occur in adults over 50 years of age. However, both types of EPHA2 coding variants were present at comparable levels in individuals with or without age-related cataract making simple genotype-phenotype correlations inconclusive.

Germ-line and somatic EPHA2 coding variants in lens aging and cataract

PubMed Central

Bennett, Thomas M.; M’Hamdi, Oussama; Hejtmancik, J. Fielding

2017-01-01

Rare germ-line mutations in the coding regions of the human EPHA2 gene (EPHA2) have been associated with inherited forms of pediatric cataract, whereas, frequent, non-coding, single nucleotide variants (SNVs) have been associated with age-related cataract. Here we sought to determine if germ-line EPHA2 coding SNVs were associated with age-related cataract in a case-control DNA panel (> 50 years) and if somatic EPHA2 coding SNVs were associated with lens aging and/or cataract in a post-mortem lens DNA panel (> 48 years). Micro-fluidic PCR amplification followed by targeted amplicon (exon) next-generation (deep) sequencing of EPHA2 (17-exons) afforded high read-depth coverage (1000x) for > 82% of reads in the cataract case-control panel (161 cases, 64 controls) and > 70% of reads in the post-mortem lens panel (35 clear lens pairs, 22 cataract lens pairs). Novel and reference (known) missense SNVs in EPHA2 that were predicted in silico to be functionally damaging were found in both cases and controls from the age-related cataract panel at variant allele frequencies (VAFs) consistent with germ-line transmission (VAF > 20%). Similarly, both novel and reference missense SNVs in EPHA2 were found in the post-mortem lens panel at VAFs consistent with a somatic origin (VAF > 3%). The majority of SNVs found in the cataract case-control panel and post-mortem lens panel were transitions and many occurred at di-pyrimidine sites that are susceptible to ultraviolet (UV) radiation induced mutation. These data suggest that novel germ-line (blood) and somatic (lens) coding SNVs in EPHA2 that are predicted to be functionally deleterious occur in adults over 50 years of age. However, both types of EPHA2 coding variants were present at comparable levels in individuals with or without age-related cataract making simple genotype-phenotype correlations inconclusive. PMID:29267365

Non-subjective cataract analysis and its application in space radiation risk assessment

NASA Technical Reports Server (NTRS)

Wu, B.; Medvedovsky, C.; Worgul, B. V.

1994-01-01

Experimental animal studies and human observations suggest that the question is not whether or not prolonged space missions will cause cataracts to appear prematurely in the astronauts, but when and to what degree. Historically the major impediment to radiation cataract follow-up has been the necessarily subjective nature of assessing the degree of lens transparency. This has spurred the development of instruments which produce video images amenable to digital analysis. One such system, the Zeiss Scheimpflug slit lamp measuring system (SLC), was incorporated into our ongoing studies of radiation cataractogenesis. It was found that the Zeiss SLC measuring system has high resolution and permits the acquisition of reproducible images of the anterior segment of the eye. Our results, based on about 650 images of the rats lens, and followed over a period of 91 weeks of radiation cataract development, showed that the Integrated Optical Density (IOD) of the lens correlated well with conventional assessment with the added advantages of objectivity, permanent and transportable records and linearity as cataracts become more severe. This continuous data acquisition, commencing with cataract onset, can proceed through more advanced stages. The SLC exhibits much greater sensitivity reflected in a continuously progressive severity despite the artifactual plateaus in staging which occur using conventional scoring methods. Systems such as the Zeiss SLC should be used to monitor astronauts frequent visits to low earth orbit to obtain a longitudinal data-base on the influence of this activity on the lens.

Eye lens dosimetry in anesthesiology: a prospective study.

PubMed

Vaes, Bart; Van Keer, Karel; Struelens, Lara; Schoonjans, Werner; Nijs, Ivo; Vandevenne, Jan; Van Poucke, Sven

2017-04-01

The eye lens is one of the most sensitive organs for radiation injury and exposure might lead to radiation induced cataract. Eye lens dosimetry in anesthesiology has been published in few clinical trials and an active debate about the causality of radiation induced cataract is still ongoing. Recently, the International Commission on Radiological Protection (ICRP) recommended a reduction in the annual dose limit for occupational exposure for the lens of the eye from 150 to 20 mSv, averaged over a period of 5 years, with the dose in a single year not exceeding 50 mSv. This prospective study investigated eye lens dosimetry in anesthesiology practice during a routine year of professional activity. The radiation exposure measured represented the exposure in a normal working schedule of a random anesthesiologist during 1 month and this cumulative eye lens dose was extrapolated to 1 year. Next, eye lens doses were measured in anesthesiology during neuro-embolisation procedures, radiofrequency ablations or vertebroplasty/kyphoplasty procedures. The eye lens doses are measured in terms of the dose equivalent H p (3) with the Eye-D dosimeter (Radcard, Poland) close to the right eye (on the temple). In 16 anesthesiologists, the estimated annual eye lens doses range from a minimum of 0.4 mSv to a maximum of 3.5 mSv with an average dose of 1.33 mSv. Next, eye lens doses were measured for nine neuro-embolisation procedures, ten radiofrequency ablations and six vertebroplasty/kyphoplasty procedures. Average eye lens doses of 77 ± 76 µSv for neuro-embolisations, 38 ± 34 µSv for cardiac ablations and 40 ± 44 µSv for vertebro-/kyphoplasty procedures were recorded. The maximum doses were respectively 264, 97 and 122 µSv. This study demonstrated that the estimated annual eye lens dose is well below the revised ICRP's limit of 20 mSv/year. However, we demonstrated high maximum and average doses during neuro-embolisation, cardiac ablation and vertebro-/kyphoplasty procedures. With radiation induced cataract being explained as a possible stochastic effect, without a threshold dose, anesthesiologists who regularly work in a radiological environment should remain vigilant and maintain radiation safety standards at all times. This includes adequately protective equipment (protection shields, apron, thyroid shield and leaded eye wear), keeping distance, routine monitoring and appropriate education.

Association of Radiation Dose to the Eyes With the Risk for Cataract After Nonretinoblastoma Solid Cancers in Childhood.

PubMed

Allodji, Rodrigue S; Diallo, Ibrahima; El-Fayech, Chiraz; Kahlouche, Amar; Dumas, Agnès; Schwartz, Boris; Oberlin, Odile; Benadjaoud, Mohamed Amine; Labbé, Martine; Jackson, Angela; Bullet, Julien; Rubino, Carole; Haddy, Nadia; De Vathaire, Florent

2016-04-01

Few studies have been published on the association of the radiation dose received to the eyes during radiotherapy (RT) for childhood cancer and the risk for later cataract. To investigate the risk for cataract after treatment of nonretinoblastoma solid cancer in childhood. The study used data from the Euro2K cohort that includes 4389 5-year survivors of solid tumors treated from January 1, 1945, to December 31, 1985; of these, 3172 patients were treated in France. A self-reported questionnaire was sent to French survivors from September 1, 2005, to December 31, 2012, when follow-up was considered completed for this study. However, 619 patients died before the beginning of the study and 128 patients treated for a retinoblastoma or who underwent enucleation were excluded. Likewise, 429 patients with unknown addresses or who did not return the consent form and 163 nonresponders did not participate. The remaining 1833 patients who completed the questionnaire underwent analysis for this study from June 1, 2014, to December 7, 2015. Radiation doses in both eyes for individuals were estimated for all patients who had received RT. The role of the radiation dose in cataract risk was investigated using the Cox proportional hazard regression model and the excess relative or the absolute risk model. The role of ctytotoxic chemotherapy was also investigated. The 1833 patients (961 men [52.4%]; 872 women [47.6%]; mean [SD] age, 37.0 [8.5]) who returned the questionnaire were included in the analysis. After a mean follow-up of 32 years, 33 patients with unilateral or bilateral cataract were identified, for a total of 47 cataract events. The 47 events were validated by medical record review and by contacting the patients and the corresponding medical physician or ophthalmologist to obtain copies of diagnostic examinations or surgical reports. Overall, in a multivariable Cox proportional hazard regression analysis, patients who received RT had a 4.4-fold (95% CI, 1.5- to 13.0-fold) increased risk for cataract compared with patients who did not receive RT. Exposure to radiation doses of at least 10 Gy to the eyes increased the hazard ratio 39-fold (95% CI, 12.0- to 127.9-fold), relative to no radiation exposure. Although based on few patients, a strong increase in cataract risk (hazard ratio, 26.3; 95% CI, 7.1-96.6) was observed in patients treated with melphalan hydrochloride. This study can inform guideline-based recommendations for long-term follow-up for cataract.

Space Radiation and Cataracts (LBNL Summer Lecture Series)

ScienceCinema

Blakely, Eleanor [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Life Sciences Division

2018-01-23

Summer Lecture Series 2009: Eleanor Blakely, radiation biologist of the Life Sciences Division at Lawrence Berkeley National Laboratory, has been a scientist at Berkeley Lab since 1975. She is studying the effect of radiation on cataracts which concerns not only cancer patients, but also astronauts. As astronauts spend increasingly longer time in space, the effects of cosmic radiation exposure will become an increasingly important health issue- yet there is little human data on these effects. Blakely reviews this emerging field and the contributions made at Berkeley Lab

Atm heterozygous mice are more sensitive to radiation-induced cataracts than are their wild-type counterparts

NASA Technical Reports Server (NTRS)

Worgul, Basil V.; Smilenov, Lubomir; Brenner, David J.; Junk, Anna; Zhou, Wei; Hall, Eric J.

2002-01-01

It is important to know whether the human population includes genetically predisposed radiosensitive subsets. In vitro studies have shown that cells from individuals homozygous for ataxia telangiectasia (A-T) are much more radiosensitive than cells from unaffected individuals. Although cells heterozygous for the ATM gene (ATM(+/-)) may be slightly more radiosensitive in vitro, it remained to be determined whether the greater susceptibility of ATM(+/-) cells translates into an increased sensitivity for late effects in vivo, though there is a suggestion that radiotherapy patients that are heterozygous for the ATM gene may be more at risk of developing late normal tissue damage. We chose cataractogenesis in the lens as a means to assay for the effects of ATM deficiency in a late-responding tissue. One eye of wild-type, Atm heterozygous and homozygous knockout mice was exposed to 0.5-, 1.0-, 2.0-, or 4.0-Gy x rays. The animals were followed weekly for cataract development by conventional slit-lamp biomicroscopy. Cataract development in the animals of all three groups was strongly dependent on dose. The lenses of homozygous mice were the first to opacify at any given dose. Most important in the present context is that cataracts appeared earlier in the heterozygous versus wild-type animals. The data suggest that ATM heterozygotes in the human population may also be radiosensitive. This may influence the choice of individuals destined to be exposed to higher than normal doses of radiation, such as astronauts, and may also suggest that radiotherapy patients who are ATM heterozygotes could be predisposed to increased late normal tissue damage.

Orally Active Multi-Functional Antioxidants Delay Cataract Formation in Streptozotocin (Type 1) Diabetic and Gamma-Irradiated Rats

PubMed Central

Randazzo, James; Zhang, Peng; Makita, Jun; Blessing, Karen; Kador, Peter F.

2011-01-01

Background Age-related cataract is a worldwide health care problem whose progression has been linked to oxidative stress and the accumulation of redox-active metals. Since there is no specific animal model for human age-related cataract, multiple animal models must be used to evaluate potential therapies that may delay and/or prevent cataract formation. Methods/Principal Findings Proof of concept studies were conducted to evaluate 4-(5-hydroxypyrimidin-2-yl)-N,N-dimethyl-3,5-dioxopiperazine-1-sulfonamide (compound 4) and 4-(5-hydroxy-4,6-dimethoxypyrimidin-2-yl)-N,N-dimethyl-3,5-dioxopiperazine-1-sulfonamide (compound 8), multi-functional antioxidants that can independently chelate redox metals and quench free radicals, on their ability to delay the progression of diabetic “sugar” cataracts and gamma radiation-induced cataracts. Prior to 15 Gy of whole head irradiation, select groups of Long Evans rats received either diet containing compound 4 or 8, or a single i.p. injection of panthethine, a radioprotective agent. Compared to untreated, irradiated rats, treatment with pantethine, 4 and 8 delayed initial lens changes by 4, 47, and 38 days, respectively, and the average formation of posterior subcapsular opacities by 23, 53 and 58 days, respectively. In the second study, select groups of diabetic Sprague Dawley rats were administered chow containing compounds 4, 8 or the aldose reductase inhibitor AL1576. As anticipated, treatment with AL1576 prevented cataract by inhibiting sorbitol formation in the lens. However, compared to untreated rats, compounds 4 and 8 delayed vacuole formation by 20 days and 12 days, respectively, and cortical cataract formation by 8 and 3 days, respectively, without reducing lenticular sorbitol. Using in vitro lens culture in 30 mM xylose to model diabetic “sugar” cataract formation, western blots confirmed that multi-functional antioxidants reduced endoplasmic reticulum stress. Conclusions/Significance Multi-functional antioxidants delayed cataract formation in two diverse rat models. These studies provide a proof of concept that a general cataract treatment focused on reducing oxidative stress instead of a specific mechanism of cataractogenesis can be developed. PMID:21541328

The risk of radiation exposure to the eyes of the interventional pain physician.

PubMed

Fish, David E; Kim, Andrew; Ornelas, Christopher; Song, Sungchan; Pangarkar, Sanjog

2011-01-01

It is widely accepted that the use of medical imaging continues to grow across the globe as does the concern for radiation safety. The danger of lens opacities and cataract formation related to radiation exposure is well documented in the medical literature. However, there continues to be controversy regarding actual dose thresholds of radiation exposure and whether these thresholds are still relevant to cataract formation. Eye safety and the risk involved for the interventional pain physician is not entirely clear. Given the available literature on measured radiation exposure to the interventionist, and the controversy regarding dose thresholds, it is our current recommendation that the interventional pain physician use shielded eyewear. As the breadth of interventional procedures continues to grow, so does the radiation risk to the interventional pain physician. In this paper, we attempt to outline the risk of cataract formation in the scope of practice of an interventional pain physician and describe techniques that may help reduce them.

The Risk of Radiation Exposure to the Eyes of the Interventional Pain Physician

PubMed Central

Fish, David E.; Kim, Andrew; Ornelas, Christopher; Song, Sungchan; Pangarkar, Sanjog

2011-01-01

It is widely accepted that the use of medical imaging continues to grow across the globe as does the concern for radiation safety. The danger of lens opacities and cataract formation related to radiation exposure is well documented in the medical literature. However, there continues to be controversy regarding actual dose thresholds of radiation exposure and whether these thresholds are still relevant to cataract formation. Eye safety and the risk involved for the interventional pain physician is not entirely clear. Given the available literature on measured radiation exposure to the interventionist, and the controversy regarding dose thresholds, it is our current recommendation that the interventional pain physician use shielded eyewear. As the breadth of interventional procedures continues to grow, so does the radiation risk to the interventional pain physician. In this paper, we attempt to outline the risk of cataract formation in the scope of practice of an interventional pain physician and describe techniques that may help reduce them. PMID:22091381

Estrogen Protects Lenses against Cataract Induced by Transforming Growth Factor-β (TGFβ)

PubMed Central

Hales, Angela M.; Chamberlain, Coral G.; Murphy, Christopher R.; McAvoy, John W.

1997-01-01

Cataract, already a major cause of visual impairment and blindness, is likely to become an increasing problem as the world population ages. In a previous study, we showed that transforming growth factor-β (TGFβ) induces rat lenses in culture to develop opacities and other changes that have many features of human subcapsular cataracts. Here we show that estrogen protects against cataract. Lenses from female rats are more resistant to TGFβ-induced cataract than those from males. Furthermore, lenses from ovariectomized females show increased sensitivity to the damaging effects of TGFβ and estrogen replacement in vivo, or exposure to estrogen in vitro, restores resistance. Sex-dependent and estrogen-related differences in susceptibility to cataract formation, consistent with a protective role for estrogen, have been noted in some epidemiological studies. The present study in the rat indicates that estrogen provides protection against cataract by countering the damaging effects of TGFβ. It also adds to an increasing body of evidence that hormone replacement therapy protects postmenopausal women against various diseases. PMID:9016876

Caffeine Eye Drops Protect Against UV-B Cataract

PubMed Central

Kronschläger, Martin; Löfgren, Stefan; Yu, Zhaohua; Talebizadeh, Nooshin; Varma, Shambhu D.; Söderberg, Per

2013-01-01

The purpose of this study was to investigate if topically applied caffeine protects against in vivo ultraviolet radiation cataract and if so, to estimate the protection factor. Three experiments were carried out. First, two groups of Sprague-Dawley rats were pre-treated with a single application of either placebo or caffeine eye drops in both eyes. All animals were then unilaterally exposed in vivo to 8 kJ/m2 UV-B radiation for 15 min. One week later, the lens GSH levels were measured and the degree of cataract was quantified by measurement of in vitro lens light scattering. In the second experiment, placebo and caffeine pre-treated rats were divided in five UV-B radiation dose groups, receiving 0.0, 2.6, 3.7, 4.5 or 5.2 kJ/m2 UV-B radiation in one eye. Lens light scattering was determined after one week. In the third experiment, placebo and caffeine pre-treated rats were UV-B-exposed and the presence of activated caspase-3 was visualized by immunohistochemistry. There was significantly less UV-B radiation cataract in the caffeine group than in the placebo group (95% confidence interval for mean difference in lens light scattering between the groups = 0.10 ± 0.05 tEDC), and the protection factor for caffeine was 1.23. There was no difference in GSH levels between the placebo- and the caffeine group. There was more caspase-3 staining in UV-B-exposed lenses from the placebo group than in UV-B-exposed lenses from the caffeine group. Topically applied caffeine protects against ultraviolet radiation cataract, reducing lens sensitivity 1.23 times. PMID:23644096

Cataract production in mice by heavy charged particles

NASA Technical Reports Server (NTRS)

Ainsworth, E. J.; Jose, U.; Yang, V. V.; Barker, M. E.

1981-01-01

The cataractogenic effects of heavy charged particles are evaluated in mice in relation to dose and ionization density. The relative biological effectiveness in relation to linear energy transfer for various particles is considered. Results indicated that low single doses (5 to 20 rad) of Fe 56 or Ar 40 particles are cataractogenic at 11 to 18 months after irradiation; onset and density of the opacification are dose related and cataract density (grade) at 9, 11, 13, and 16 months after irradiation shows partial linear energy transfer dependence. The severity of cataracts is reduced significantly when 417 rad of Co 60 gamma radiation is given in 24 weekly 17 rad fractions compared to giving this radiation as a single dose, but cataract severity is not reduced by fractionation of C12 doses over 24 weeks.

Mimicking cataract-induced visual dysfunction by means of protein denaturation in egg albumen

NASA Astrophysics Data System (ADS)

Mandracchia, B.; Finizio, A.; Ferraro, P.

2016-03-01

As the world's population ages, cataract-induced visual dysfunction and blindness is on the increase. This is a significant global problem. The most common symptoms of cataracts are glared and blurred vision. Usually, people with cataract have trouble seeing and reading at distance or in low light and also their color perception is altered. Furthermore, cataract is a sneaky disease as it is usually a very slow but progressive process, which creates adaptation so that patients find it difficult to recognize. All this can be very difficult to explain, so we built and tested an optical device to help doctors giving comprehensive answers to the patients' symptoms. This device allows visualizing how cataract impairs vision mimicking the optical degradation of the crystalline related cataracts. This can be a valuable optical tool for medical education as well as to provide a method to illustrate the patients how cataract progression process will affect their vision.

Prevention and reversal of selenite-induced cataracts by N-acetylcysteine amide in Wistar rats.

PubMed

Maddirala, Yasaswi; Tobwala, Shakila; Karacal, Humeyra; Ercal, Nuran

2017-04-26

The present study sought to evaluate the efficacy of N-acetylcysteine amide (NACA) eye drops in reversing the cataract formation induced by sodium selenite in male Wistar rat pups. Forty male Wistar rat pups were randomly divided into a control group, an N-acetylcysteine amide-only group, a sodium selenite-induced cataract group, and a NACA-treated sodium selenite-induced cataract group. Sodium selenite was injected intraperitoneally on postpartum day 10, whereas N-acetylcysteine amide was injected intraperitoneally on postpartum days 9, 11, and 13 in the respective groups. Cataracts were evaluated at the end of week 2 (postpartum day 14) when the rat pups opened their eyes. N-acetylcysteine amide eye drops were administered beginning on week 3 until the end of week 4 (postpartum days 15 to 30), and the rats were sacrificed at the end of week 4. Lenses were isolated and examined for oxidative stress parameters such as glutathione, lipid peroxidation, and calcium levels along with the glutathione reductase and thioltransferase enzyme activities. Casein zymography and Western blot of m-calpain were performed using the water soluble fraction of lens proteins. Morphological examination of the lenses in the NACA-treated group indicated that NACA was able to reverse the cataract grade. In addition, glutathione level, thioltransferase activity, m-calpain activity, and m-calpain level (as assessed by Western blot) were all significantly higher in the NACA-treated group than in the sodium selenite-induced cataract group. Furthermore, sodium selenite- injected rat pups had significantly higher levels of malondialdehyde, glutathione reductase enzyme activity, and calcium levels, which were reduced to control levels upon treatment with NACA. The data suggest that NACA has the potential to significantly improve vision and decrease the burden of cataract-related loss of function. Prevention and reversal of cataract formation could have a global impact. Development of pharmacological agents like NACA may eventually prevent cataract formation in high-risk populations and may prevent progression of early-stage cataracts. This brings a paradigm shift from expensive surgical treatment of cataracts to relatively inexpensive prevention of vision loss.

Selenite and ebselen supplementation attenuates D-galactose-induced oxidative stress and increases expression of SELR and SEP15 in rat lens.

PubMed

Dai, Jie; Zhou, Jun; Liu, Hongmei; Huang, Kaixun

2016-12-01

Selenite and ebselen supplementation has been shown to possess anti-cataract potential in some experimental animal models of cataract, however, the underlying mechanisms remain unclear. The present study was designed to evaluate the anti-cataract effects and the underlying mechanisms of selenite and ebselen supplementation on galactose induced cataract in rats, a common animal model of sugar cataract. Transmission electron microscopy images of lens fiber cells (LFC) and lens epithelial cells (LEC) were observed in D-galactose-induced experimental cataractous rats treated with or without selenite and ebselen, also redox homeostasis and expression of proteins such as selenoprotein R (SELR), 15kD selenoprotein (SEP15), superoxide dismutase 1 (SOD1), catalase (CAT), β-crystallin protein, aldose reductase (AR) and glucose-regulated protein 78 (GRP78) were estimated in the lenses. The results showed that D-galactose injection injured rat lens and resulted in cataract formation; however, selenite and ebselen supplementation markedly alleviated ultrastructural injury of LFC and LEC. Moreover, selenite and ebselen supplementation could mitigate the oxidative damage in rat lens and increase the protein expressions of SELR, SEP15, SOD1, CAT and β-crystallin, as well as decrease the protein expressions of AR and GRP78. Taken together, these findings for the first time reveal the anti-cataract potential of selenite and ebselen in galactosemic cataract, and provide important new insights into the anti-cataract mechanisms of selenite and ebselen in sugar cataract.

Cataractogenic potential of ionizing radiations in animal models that simulate man

NASA Technical Reports Server (NTRS)

Lett, J. T.; Cox, A. B.; Lee, A. C.

1986-01-01

Aspects of experiments on radiation-induced lenticular opacification during the life spans of two animal models, the New Zealand white rabbit and the rhesus monkey, are compared and contrasted with published results from a life-span study of another animal model, the beagle dog, and the most recent data from the ongoing study of the survivors from radiation exposure at Hiroshima and Nagasaki. An important connection among the three animal studies is that all the measurements of cataract indices were made by one of the authors (Lee), so variation from personal subjectivity was reduced to a minimum. The primary objective of the rabbit experiments (radiations involved: Fe-56, Ar-40, and Ne-20 ions and Co-60 gamma photons) is an evaluation of hazards to astronauts from Galactic particulate radiations. An analogous evaluation of hazards from solar flares during space flight is being made with monkeys exposed to 32, 55, 138 and 400-MeV protons. Conclusions are drawn about the proper use of animal models to simulate radiation responses in man and the levels of radiation-induced lenticular opacification that pose risks to man in space.

Nonlinear ionizing radiation-induced changes in eye lens cell proliferation, cyclin D1 expression and lens shape.

PubMed

Markiewicz, Ewa; Barnard, Stephen; Haines, Jackie; Coster, Margaret; van Geel, Orry; Wu, Weiju; Richards, Shane; Ainsbury, Elizabeth; Rothkamm, Kai; Bouffler, Simon; Quinlan, Roy A

2015-04-01

Elevated cataract risk after radiation exposure was established soon after the discovery of X-rays in 1895. Today, increased cataract incidence among medical imaging practitioners and after nuclear incidents has highlighted how little is still understood about the biological responses of the lens to low-dose ionizing radiation (IR). Here, we show for the first time that in mice, lens epithelial cells (LECs) in the peripheral region repair DNA double strand breaks (DSB) after exposure to 20 and 100 mGy more slowly compared with circulating blood lymphocytes, as demonstrated by counts of γH2AX foci in cell nuclei. LECs in the central region repaired DSBs faster than either LECs in the lens periphery or lymphocytes. Although DSB markers (γH2AX, 53BP1 and RAD51) in both lens regions showed linear dose responses at the 1 h timepoint, nonlinear responses were observed in lenses for EdU (5-ethynyl-2'-deoxy-uridine) incorporation, cyclin D1 staining and cell density after 24 h at 100 and 250 mGy. After 10 months, the lens aspect ratio was also altered, an indicator of the consequences of the altered cell proliferation and cell density changes. A best-fit model demonstrated a dose-response peak at 500 mGy. These data identify specific nonlinear biological responses to low (less than 1000 mGy) dose IR-induced DNA damage in the lens epithelium.

Nonlinear ionizing radiation-induced changes in eye lens cell proliferation, cyclin D1 expression and lens shape

PubMed Central

Markiewicz, Ewa; Barnard, Stephen; Haines, Jackie; Coster, Margaret; van Geel, Orry; Wu, Weiju; Richards, Shane; Ainsbury, Elizabeth; Rothkamm, Kai; Bouffler, Simon; Quinlan, Roy A.

2015-01-01

Elevated cataract risk after radiation exposure was established soon after the discovery of X-rays in 1895. Today, increased cataract incidence among medical imaging practitioners and after nuclear incidents has highlighted how little is still understood about the biological responses of the lens to low-dose ionizing radiation (IR). Here, we show for the first time that in mice, lens epithelial cells (LECs) in the peripheral region repair DNA double strand breaks (DSB) after exposure to 20 and 100 mGy more slowly compared with circulating blood lymphocytes, as demonstrated by counts of γH2AX foci in cell nuclei. LECs in the central region repaired DSBs faster than either LECs in the lens periphery or lymphocytes. Although DSB markers (γH2AX, 53BP1 and RAD51) in both lens regions showed linear dose responses at the 1 h timepoint, nonlinear responses were observed in lenses for EdU (5-ethynyl-2′-deoxy-uridine) incorporation, cyclin D1 staining and cell density after 24 h at 100 and 250 mGy. After 10 months, the lens aspect ratio was also altered, an indicator of the consequences of the altered cell proliferation and cell density changes. A best-fit model demonstrated a dose-response peak at 500 mGy. These data identify specific nonlinear biological responses to low (less than 1000 mGy) dose IR-induced DNA damage in the lens epithelium. PMID:25924630

Atm heterozygous mice are more sensitive to radiation-induced cataracts than are their wild-type counterparts

PubMed Central

Worgul, Basil V.; Smilenov, Lubomir; Brenner, David J.; Junk, Anna; Zhou, Wei; Hall, Eric J.

2002-01-01

It is important to know whether the human population includes genetically predisposed radiosensitive subsets. In vitro studies have shown that cells from individuals homozygous for ataxia telangiectasia (A-T) are much more radiosensitive than cells from unaffected individuals. Although cells heterozygous for the ATM gene (ATM+/−) may be slightly more radiosensitive in vitro, it remained to be determined whether the greater susceptibility of ATM+/− cells translates into an increased sensitivity for late effects in vivo, though there is a suggestion that radiotherapy patients that are heterozygous for the ATM gene may be more at risk of developing late normal tissue damage. We chose cataractogenesis in the lens as a means to assay for the effects of ATM deficiency in a late-responding tissue. One eye of wild-type, Atm heterozygous and homozygous knockout mice was exposed to 0.5-, 1.0-, 2.0-, or 4.0-Gy x rays. The animals were followed weekly for cataract development by conventional slit-lamp biomicroscopy. Cataract development in the animals of all three groups was strongly dependent on dose. The lenses of homozygous mice were the first to opacify at any given dose. Most important in the present context is that cataracts appeared earlier in the heterozygous versus wild-type animals. The data suggest that ATM heterozygotes in the human population may also be radiosensitive. This may influence the choice of individuals destined to be exposed to higher than normal doses of radiation, such as astronauts, and may also suggest that radiotherapy patients who are ATM heterozygotes could be predisposed to increased late normal tissue damage. PMID:12119422

Evolution of light scattering and redox balance in the rat lens after in vivo exposure to close-to-threshold dose ultraviolet radiation.

PubMed

Wang, Jing; Löfgren, Stefan; Dong, Xiuqin; Galichanin, Konstantin; Söderberg, Per G

2010-11-01

To investigate the evolution of cataract development and glutathione redox balance in the rat lens after in vivo close-to-threshold dose exposure to ultraviolet radiation (UVR) around 300 nm. Three groups of 10 Sprague-Dawley rats were unilaterally exposed to 8 kJ/m² UVR-300 nm for 15 min, and a fourth group of 10 rats was kept without UVR exposure as nonexposed control animals. The exposed animals were killed at 1, 3 and 7 days after exposure. Both lenses from all animals were extracted and photographed and the intensity of forward light scattering was measured quantitatively. Thereafter, the lenses were homogenized. The concentration of reduced glutathione (GSH) and oxidized glutathione (GSSG), and the activity of glutathione reductase (GR) and glutathione peroxidase (GPx), respectively, were determined spectrophotometrically. The mean paired differences between exposed and nonexposed lenses were used as primary data in the statistical analyses. All exposed lenses developed cataract. Lens light scattering increased throughout the 7 days after UVR exposure. GSH concentration and GPx rate transiently increased at 1 day after exposure and then decreased throughout follow-up, with GSH concentration having a negative balance at the end. GSSG concentration and GR activity did not change after UVR exposure. In vivo close-to-threshold UVR exposure induces a gradual increase in rat lens opacification/cataract development and time dependently alters the redox balance in the lens. © 2010 The Authors. Journal compilation © 2010 Acta Ophthalmol.

Effects of two antioxidants; α-lipoic acid and fisetin against diabetic cataract in mice.

PubMed

Kan, Emrah; Kiliçkan, Elif; Ayar, Ahmet; Çolak, Ramis

2015-02-01

The purpose of this study was to determine whether α-lipoic acid and fisetin have protective effects against cataract in a streptozotocin-induced experimental cataract model. Twenty-eight male BALB/C mice were made diabetic by the intraperitoneal administration of streptozotocin (200 mg/kg). Three weeks after induction of diabetes, mice were divided randomly into 4 groups in which each group contained 7 mice; fisetin-treated group (group 1), α-lipoic acid-treated group (group 2), fisetin placebo group (group 3), α-lipoic acid placebo group (group 4). Fisetin and α-lipoic acid were administered intraperitoneally weekly for 5 weeks. Cataract development was assessed at the end of 8 weeks by slit lamp examination, and cataract formation was graded using a scale. All groups developed at least grade 1 cataract formation. In the fisetin-treated group, the cataract stages were significantly lower than in the placebo group (p = 0.02). In the α-lipoic acid-treated group, the cataract stages were lower than in the placebo group but it did not reach to a significant value. Both fisetin and α-lipoic acid had a protective effect on cataract development in a streptozotocin-induced experimental cataract model. The protective effect of fisetin appears as though more effective than α-lipoic acid.

Lysergic acid diethylamide: effects on the developing mouse lens.

PubMed

Hanaway, J K

1969-05-02

High doses (5 x 10-(6) gram) of LSD-25 given to Swiss-Webster females on gestation days 6, 7, 8, or 9 caused a high incidence of anterior subcapsular lens abnormalities. Accompanying this, the lens epithelium was often hyperplastic, and the lens bow was widened posteriorly in a fashion similar to cataracts induced by x-radiation. Confirmation of this effect of LSD-25 was obtained by a (duplicate) experiment 1 year after the observations reported.

Ultraviolet Radiation–Induced Cataract in Mice: The Effect of Age and the Potential Biochemical Mechanism

PubMed Central

Zhang, Jie; Yan, Hong; Löfgren, Stefan; Tian, Xiaoli; Lou, Marjorie F.

2012-01-01

Purpose. To study the effect of age on the morphologic and biochemical alterations induced by in vivo exposure of ultraviolet radiation (UV). Methods. Young and old C57BL/6 mice were exposed to broadband UVB+UVA and euthanized after 2 days. Another batch of UV-exposed young mice was monitored for changes after 1, 2, 4, and 8 days. Age-matched nonexposed mice served as controls. Lens changes were documented in vivo by slit-lamp biomicroscopy and dark field microscopy photographs ex vivo. Lens homogenates were analyzed for glutathione (GSH) level, and the activities of thioredoxin (Trx), thioltransferase (TTase), and glyceraldehyde-3-phosphate dehydrogenase (G3PD). Glutathionylated lens proteins (PSSGs) were detected by immunoblotting using GSH antibody. Western blot analysis was also done for the expression levels of TTase and Trx. Results. Both age groups developed epithelial and superficial anterior subcapsular cataract at 2 days postexposure. The lens GSH level and G3PD activity were decreased, and PSSGs were elevated in both age groups, but more prominent in the older mice. TTase and Trx activity and protein expression were elevated only in the young mice. Interestingly, lens TTase and Trx in the young mice showed a transient increase, peaking at 2 days after UV exposure and returning to baseline at day 8, corroborated by lens transparency. Conclusions. The lenses of old mice were more susceptible to UV radiation–induced cataract. The upregulated TTase and Trx likely provided oxidation damage repair in the young mice. PMID:23010639

Etiopathogenesis of cataract: An appraisal

PubMed Central

Gupta, Varun B; Rajagopala, Manjusha; Ravishankar, Basavaiah

2014-01-01

Natural eye lens is a crystalline substance to produce a clear passage for light. Cataract is opacity within the clear lens of the eye and is the dominant cause of socio-medical problem i.e., blindness worldwide. The only available treatment of cataract is surgery. However, insufficient surgical facilities in poor and developing countries and post-operative complications inspire researchers to find out other modes of treatment for cataract. In this review, an attempt has been made to appraise various etiological factors of cataract to make their perception clear to build up counterpart treatment. Present study is an assortment of various available literatures and electronic information in view of cataract etiopathogenesis. Various risk factors have been identified in development of cataracts. They can be classified in to genetic factors, ageing (systemic diseases, nutritional and trace metals deficiencies, smoking, oxidative stress etc.), traumatic, complicated (inflammatory and degenerative diseases of eye), metabolic (diabetes, galactosemia etc.), toxic substances including drugs abuses, alcohol etc., radiation (ultraviolet, electromagnetic waves etc.) are implicated as significant risk factors in the development of cataract. PMID:24618482

The NASA-Sponsored Study of Cataract in Astronauts (NASCA). Relationship of Exposure to Radiation in Space and the Risk of Cataract Incidence and Progression. Report 1: Recruitment and Methodology

NASA Technical Reports Server (NTRS)

Chylack, Leo T.; Peterson, Leif E.; Feiveson, Alan H.; Wear, Mary; Manuel, F. Keith

2007-01-01

The NASA Study of Cataract in Astronauts (NASCA) is a five-year, multi-centered, investigation of lens opacification in populations of U.S. astronauts, military pilots, and ground-based (nonaviator) comparison participants. For astronauts, the explanatory variable of most interest is radiation exposure during space flight, however to properly evaluate its effect, the secondary effects of age, nutrition, general health, solar ocular exposure, and other confounding variables encountered in non-space flight must also be considered. NASCA contains an initial baseline, cross-sectional objective assessment of the severity of cortical (C), nuclear (N), and posterior subcapsular (PSC) lens opacification, and annual follow-on assessments of severity and progression of these opacities in the population of astronauts and in participants sampled from populations of military pilots and ground-based exposure controls. From these data, NASCA will estimate the degree to which space radiation affects lens opacification for astronauts and how the overall risks of each cataract type for astronauts compared with those of the other exposure control groups after adjusting for differences in age and other explanatory variables.

Cataractogenic potential of ionizing radiations in animal models that simulate man

NASA Astrophysics Data System (ADS)

Lett, J. T.; Cox, A. B.; Lee, A. C.

Aspects of experiments on radiation-induced lenticular opacification during the life spans of two animal models, the New Zealand white rabbit and the rhesus monkey, are compared and contrasted with published results from a life span study of another animal model, the beagle dog, and the most recent data from the ongoing study of the survivors from radiation exposure at Hiroshima and Nagasaki. An important connection among the three animal studies is that all the measurements of cataract indices were made by one of the authors (A.C.L.), so variation from personal subjectivity was reduced to a minimum. The primary objective of the rabbit experiments (radiations involved: 56Fe, 40Ar and 20Ne ions and 60Co γ photons) is an evaluation of hazards to astronauts from galactic particulate radiations. An analogous evaluation of hazards from solar flares during space flight is being made with monkeys exposed to 32, 55, 138 and 400 MeV protons. Conclusions are drawn about the proper use of animal models to simulate radiation responses in man and the levels of radiation-induced lenticular opacification that pose risks to man in space.

mBAND analysis for high- and low-LET radiation-induced chromosome aberrations: a review.

PubMed

Hada, Megumi; Wu, Honglu; Cucinotta, Francis A

2011-06-03

During long-term space travel or cancer therapy, humans are exposed to high linear energy transfer (LET) energetic heavy ions. High-LET radiation is much more effective than low-LET radiation in causing various biological effects, including cell inactivation, genetic mutations, cataracts and cancer induction. Most of these biological endpoints are closely related to chromosomal damage, and cytogenetic damage can be utilized as a biomarker for radiation insults. Epidemiological data, mainly from survivors of the atomic bomb detonations in Japan, have enabled risk estimation from low-LET radiation exposures. The identification of a cytogenetic signature that distinguishes high- from low-LET exposure remains a long-term goal in radiobiology. Recently developed fluorescence in situ hybridization (FISH)-painting methodologies have revealed unique endpoints related to radiation quality. Heavy-ions induce a high fraction of complex-type exchanges, and possibly unique chromosome rearrangements. This review will concentrate on recent data obtained with multicolor banding in situ hybridization (mBAND) methods in mammalian cells exposed to low- and high-LET radiations. Chromosome analysis with mBAND technique allows detection of both inter- and intrachromosomal exchanges, and also distribution of the breakpoints of aberrations. 2011 Elsevier B.V. All rights reserved.

Towards Space Exploration of Moon, Mars Neos: Radiation Biological Basis

NASA Astrophysics Data System (ADS)

Hellweg, Christine; Baumstark-Khan, Christa; Berger, Thomas; Reitz, Guenther

2016-07-01

Radiation has emerged as the most critical issue to be resolved for long-term missions both orbital and interplanetary. Astronauts are constantly exposed to galactic cosmic radiation (GCR) of various energies with a low dose rate. Primarily late tissue sequels like genetic alterations, cancer and non-cancer effects, i.e. cataracts and degenerative diseases of e.g. the central nervous system or the cardiovascular system, are the potential risks. Cataracts were observed to occur earlier and more often in astronauts exposed to higher proportions of galactic ions (Cucinotta et al., 2001). Predictions of cancer risk and acceptable radiation exposure in space are subject to many uncertainties including the relative biological effectiveness (RBE) of space radiation especially heavy ions, dose-rate effects and possible interaction with microgravity and other spaceflight environmental factors. The initial cellular response to radiation exposure paves the way to late sequelae and starts with damage to the DNA which complexity depends on the linear energy transfer (LET) of the radiation. Repair of such complex DNA damage is more challenging and requires more time than the repair of simple DNA double strand breaks (DSB) which can be visualized by immunofluorescence staining of the phosphorylated histone 2AX (γH2AX) and might explain the observed prolonged cell cycle arrests induced by high-LET in comparison to low-LET irradiation. Unrepaired or mis-repaired DNA DSB are proposed to be responsible for cell death, mutations, chromosomal aberrations and oncogenic cell transformation. Cell killing and mutation induction are most efficient in an LET range of 90-200 keV/µm. Also the activation of transcription factors such as Nuclear Factor κB (NF-κB) and gene expression shaping the cellular radiation response depend on the LET with a peak RBE between 90 and 300 keV/µm. Such LET-RBE relationships were observed for cataract and cancer induction by heavy ions in laboratory animals, with varying maximal efficiencies. Furthermore, there is always the added risk of acute exposure to high proton fluxes during a solar particle event (SPE), which can threaten immediate survival of the astronauts in case of insufficient shielding by eliciting the acute radiation syndrome. Its symptoms depend on absorbed total radiation dose, type of radiation, the dose distribution in the body and the individual radiation sensitivity. After the prodromal stage with nausea and vomiting and a subsequent symptom-free phase, depending on dose, the hematopoietic syndrome with suppression of the acquired immune system and thrombocytopenia (0.7-4 Sv), the gastrointestinal tract syndrome (5-12 Sv) or the central nervous system syndrome (> 20 Sv) develop and they are accompanied by exacerbated innate immune responses. Exposure to large SPE has to be avoided by warning systems and stay inside a radiation shelter during the event. Treatment options encompass e.g. the administration of colony-stimulating factors (CSF), growth factors and blood transfusions to overcome the hematopoietic syndrome and the administration of antibiotics against secondary infections. A concerted action of ground-based studies and space experiments is required to improve the radiobiological basis of space radiation risk assessment and countermeasure development. References: Cucinotta FA, Manuel FK, Jones J, Iszard G, Murrey J, Djojonegro B and Wear M (2001) Space Radiation and Cataracts in Astronauts. Rad Res 156, 460-466

[Chaperon-like anticataract agents, the antiaggregants of lens crystallin. Communication 4. Study of the effect of a mixture of di- and tetrapeptides on a prolonged rat model of UV-induced cataract].

PubMed

Avetisov, S E; Polunin, G S; Sheremet, N L; Makarov, I A; Fedorov, A A; Karpova, O E; Muranov, K O; Dizhevskaia, A K; Soustov, L V; Chelnokov, E V; Bitiurin, N M; Sapogova, N V; Nemov, V V; Bodyrev, A A; Ostrovskiĭ, M A

2008-01-01

There is a potential of therapeutic action on certain stages of caractogenesis, in particular on the aggregation of water-soluble proteins of cytoplasmic lens fiber cells, giving rise to insoluble protein complexes. The effect of a combined preparation (N-acetyl carnosine and D-patethine), acting by the chaperon-like mechanism, was studied in vivo on a prolonged rat model of UV-induced cataract. The use of the combined preparation consisting of a mixture of peptides of N-acetyl carnosine and D-patethine in a ratio of 1:1 as ocular instillations and intraperitoneal injections could slow down the development of UV-induced cataract in vivo. Pathomorphological studies suggest that the combined preparation has a protective effect on lens tissue when the rat model of UV-induced cataract is employed.

Eye fluke-induced cataracts in natural fish populations: is there potential for host manipulation?

PubMed

Seppälä, O; Karvonen, A; Valtonen, E T

2011-02-01

Manipulation of host phenotype (e.g. behaviour, appearance) is suggested to be a common strategy to enhance transmission in trophically transmitted parasites. However, in many systems, evidence of manipulation comes exclusively from laboratory studies and its occurrence in natural host populations is poorly understood. Here, we examined the potential for host manipulation by Diplostomum eye flukes indirectly by quantifying the physiological effects of parasites on fish. Earlier laboratory studies have shown that Diplostomum infection predisposes fish to predation by birds (definitive hosts of the parasites) by reducing fish vision through cataract formation. However, occurrence of cataracts and the subsequent potential for host manipulation in natural fish populations has remained poorly explored. We studied the occurrence of eye fluke-induced cataracts from 7 common fish species (Gymnocephalus cernuus, Rutilus rutilus, Leuciscus leuciscus, Alburnus alburnus, Osmerus eperlanus, Coregonus lavaretus and Gasterosteus aculeatus) from the Bothnian Bay in the Baltic Sea. We found that the parasite-induced cataracts were common in fish and they also reached high levels which are likely to predispose fish to predation. However, we observed such cataracts only in species with the highest parasite abundances, which suggests that only certain hosts may be strongly affected by the infection.

A comparison of simple and realistic eye models for calculation of fluence to dose conversion coefficients in a broad parallel beam incident of protons

NASA Astrophysics Data System (ADS)

Sakhaee, Mahmoud; Vejdani-Noghreiyan, Alireza; Ebrahimi-Khankook, Atiyeh

2015-01-01

Radiation induced cataract has been demonstrated among people who are exposed to ionizing radiation. To evaluate the deterministic effects of ionizing radiation on the eye lens, several papers dealing with the eye lens dose have been published. ICRP Publication 103 states that the lens of the eye may be more radiosensitive than previously considered. Detailed investigation of the response of the lens showed that there are strong differences in sensitivity to ionizing radiation exposure with respect to cataract induction among the tissues of the lens of the eye. This motivated several groups to look deeper into issue of the dose to a sensitive cell population within the lens, especially for radiations with low energy penetrability that have steep dose gradients inside the lens. Two sophisticated mathematical models of the eye including the inner structure have been designed for the accurate dose estimation in recent years. This study focuses on the calculations of the absorbed doses of different parts of the eye using the stylized models located in UF-ORNL phantom and comparison with the data calculated with the reference computational phantom in a broad parallel beam incident of protons with energies between 20 MeV and 10 GeV. The obtained results indicate that the total lens absorbed doses of reference phantom has good compliance with those of the more sensitive regions of stylized models. However, total eye absorbed dose of these models greatly differ with each other for lower energies.

Effects of radiotherapy on uveal melanomas and adjacent tissues

PubMed Central

Groenewald, C; Konstantinidis, L; Damato, B

2013-01-01

Most uveal melanomas are treated with radiotherapy. An adequate understanding of the effects of radiation on the tumour and the healthy ocular tissues is necessary. Ionizing radiation damages cell membranes, organelles, and DNA. Irradiated cells are lysed or undergo apoptosis, necrosis, and senescence. These effects occur in tumour cells and vascular endothelial cells, resulting in tumour shrinkage, ischaemia, infarction, exudation, and fibrosis, which can cause exudative maculopathy, serous retinal detachment, rubeosis, and neovascular glaucoma (ie, ‘toxic tumour syndrome'). Such abnormalities must be distinguished from collateral damage to healthy ocular tissues that receive high doses of radiation, and these include radiation-induced retinopathy, optic neuropathy, choroidopathy, cataract, and scleral necrosis. Radiation retinopathy can be treated effectively with photodynamic therapy, anti-angiogenic agents, and intravitreal steroid injections. In some patients, optic neuropathy may improve with intravitreal steroids or anti-angiogenic agents. Neovascular glaucoma resolves with intra-cameral bevacizumab. Exudative retinal detachment can regress with intra-vitreal steroid injections. Cataract is treated in the usual manner. Scleral necrosis, if severe, may require grafting, possibly using a lamellar flap from the same eye. Depending on the bulk of the residual toxic tumour, treatment can consist of intra-vitreal steroids and/or anti-angiogenic agents, transpupillary thermotherapy or photodynamic therapy to the tumour, or surgical removal of the tumour by endo- or exo-resection. Measures aimed at preventing collateral damage include eccentric placement of ruthenium plaques or iodine seeds and delivery of a notched proton beam. The decision to treat a uveal melanoma with radiotherapy requires the ability to manage iatrogenic side effects and complications. PMID:23196647

Inhibition of aldose reductase from cataracted eye lenses by finger millet (Eleusine coracana) polyphenols.

PubMed

Chethan, S; Dharmesh, Shylaja M; Malleshi, Nagappa G

2008-12-01

Retinopathy is a major cause of blindness in the Western world, while cataract is one of the three major causes of blindness worldwide. Diabetes is one of the major risk factor in retinopathy and cataract. The prevalence of blindness in India is 15 per 1000 while cataract alone accounts for 80% of this blindness. Diabetes induced cataract is characterized by an accumulation of sorbitol which is mediated by the action of a key enzyme aldose reductase (AR). Non-enzymatic glycation (binding of glucose to protein molecule) induced during diabetes appear to be the key factor for AR mediated sugar-induced cataract. Finger millet polyphenols (FMP) being a major anti-diabetic and antioxidant component, we have evaluated them for AR inhibiting activity. Phenolic constituents in FMP such as gallic, protocatechuic, p-hydroxy benzoic, p-coumaric, vanillic, syringic, ferulic, trans-cinnamic acids and the quercetin inhibited cataract eye lens effectively, the latter was more potent with an IC(50) of 14.8nM. Structure function analysis revealed that phenolics with OH group at 4th position was important for aldose reductase inhibitory property. Also the presence of neighboring O-methyl group in phenolics denatured the AR activity. Finger millet seed coat polyphenols (SCP) has been found to inhibit AR reversibly by non-competitive inhibition. Results thus, provide a stronger evidence for the potentials of FMP in inhibiting cataractogenesis in humans.

Biometry and clinical characteristics of congenital cataracts and microphthalmia in the Miniature Schnauzer.

PubMed

Gelatt, K N; Samuelson, D A; Barrie, K P; Das, N D; Wolf, E D; Bauer, J E; Andresen, T L

1983-07-01

Forty-two Miniature Schnauzer pups and adults with congenital cataracts and microphthalmia were evaluated by serial ophthalmic examinations, slit lamp biomicroscopic photography, and A-scan ultrasonography. The cataracts were evident when the eyelids opened at 2 weeks, affecting predominantly the lens nucleus and posterior cortex. Lenticonus was evident in 19% of the cataractous lenses. Progression of the cataracts was variable and related to involvement of the equatorial and posterior cortices. Lens-induced uveitis developed in some adult dogs with advanced hypermature cataracts. The globe and lens were smaller than normal in the cataractous eyes, as ascertained by A-scan ultrasonography. Age-matched comparisons of clear lens carrier Miniature Schnauzers and normal Beagles with the cataractous Miniature Schnauzers indicated affected globes and cataractous lenses were reduced 10% to 20% in their anteroposterior lengths. The microphthalmia appeared related to the congenital microphakic cataract.

The use of the term 'radiosensitivity' through history of radiation: from clarity to confusion.

PubMed

Britel, Manon; Bourguignon, Michel; Foray, Nicolas

2018-05-01

The term 'radiosensitivity' appeared for the first time at the beginning of the 20th century, few years after the discovery of X-rays. Initially used by French and German radiologists, it illustrated the risk of radiation-induced (RI) skin reactions. From the 1950s, 'radiosensitivity' was progressively found to describe other features of RI response such as RI cancers or cataracts. To date, such confusion may raise legal issues and complexify the message addressed to general public. Here, through an historical review, we aimed to better understand how this confusion appeared. To support our historical review, a quantitative and qualitative wording analysis of the 'radiosensitivity' occurrences and its derived terms was performed with Google books, Pubmed, Web of Science™ databases, and in all the ICRP publications. While 'radiosensitivity' was historically related to RI adverse tissue events attributable to cell death, the first efforts to quantify the RI risk specific to each organ/tissue revealed some different semantic fields that are not necessarily compatible together (e.g. adverse tissue events for skin, cataracts for eyes, RI cancer for breast or thyroid). To avoid such confusion, we propose to keep the historical definition of 'radiosensitivity' to any clinical and cellular consequences of radiation attributable to cell death and to introduce the term 'radiosusceptibility' to describe the RI cancers or any feature that is attributable to cell transformation.

Grape seed extract and Zinc containing nutritional food supplement delays onset and progression of Streptozocin-induced diabetic cataract in Wistar rats.

PubMed

Satyam, Shakta Mani; Bairy, Laxminaryana Kurady; Pirasanthan, Rajadurai; Vaishnav, Rajdip Lalit

2015-05-01

Prevention of hyperglycemia and enhancement of antioxidant defense mechanisms remain major goals in the treatment of diabetic cataract. Earlier, we reported strong anti-hyperglycemic and in vitro antioxidant potential of the combined formulation of grape seed extract and Zincovit tablets. Therefore, the current study was designed to investigate effects of combined formulation of grape seed extract and Zincovit tablets against streptozocin-induced diabetic cataract in Wistar rats. Adult Wistar rats were selected and diabetes was induced by streptozocin (35 mg/kg, i.p) and divided into four groups (group II-V). The normal control (group I) and streptozocin-induced diabetic cataract control rats received only vehicle. Groups III, IV and V animals received orally 40, 80 and 160 mg/kg of combined formulation of Zincovit tablets with grape seed extract respectively for a period of 150 days. The biochemical pathways involved in the pathogenesis of cataract such as oxidative stress, polyol pathway and alterations in adenosine triphosphate, glucose-6-phosphate dehydrogenase and blood glucose were investigated, to understand the possible mechanism of action of combined formulation of grape seed extract and Zincovit tablets. Rats treated with combined formulation of grape seed extract and Zincovit tablets delayed the progression of diabetic cataract as well as it showed significant alterations in oxidative stress markers along with blood glucose, aldose reductase, glucose-6-phosphate dehydrogenase and adenosine triphosphate level in lens. Over all, the results suggest that single combined formulation of grape seed extract and Zincovit tablets may be of great value in delaying diabetic cataract of human subjects as nutritional food supplement.

Manual small incision extracapsular cataract surgery in Australia.

PubMed

van Zyl, Lourens; Kahawita, Shyalle; Goggin, Michael

2014-11-01

Examination of the results and describing the technique of manual small incision extracapsular cataract extraction on patients with advanced cataracts in urban Australia. A descriptive case series. Thirty-eight patients at three public hospitals, one tertiary and two secondary ophthalmic units in urban Australia. Forty eyes with dense mature cataracts with hand movement vision or worse underwent a planned manual small incision extracapsular cataract extraction instead of traditional phaco-emulsification. Postoperative visual aquity, surgically induced astigmatism and complications. Seventy-eight per cent of patients had an uncorrected visual acuity of 6/12 or better on the first postoperative day. Eighty-three per cent of patients had a distance corrected visual acuity of 6/9 or better 3 months postoperatively. One case was complicated by a posterior capsule rupture. No cases of endophthalmitis were reported. The summated vector mean of the surgically induced astigmatism was 0.089D at 93°. Manual small incision extracapsular cataract extraction is an efficacious cataract surgery technique with good visual outcome and is a safe alternative to phaco-emulsification in suitable cases in a first-world setting. © 2014 Royal Australian and New Zealand College of Ophthalmologists.

Amyloid Fiber Formation in Human γD-Crystallin Induced by UV-B Photodamage

PubMed Central

Moran, Sean D.; Zhang, Tianqi O.; Decatur, Sean M.; Zanni, Martin T.

2013-01-01

γD-crystallin is an abundant structural protein of the lens that is found in native and modified forms in cataractous aggregates. We establish that UV-B irradiation of γD-crystallin leads to structurally specific modifications and precipitation via two mechanisms: amorphous aggregates and amyloid fibers. UV-B radiation causes cleavage of the backbone, in large measure near the interdomain interface, where side chain oxidations are also concentrated. 2D IR spectroscopy and expressed protein ligation localize fiber formation exclusively to the C-terminal domain of γD-crystallin. The native β-sandwich domains are not retained upon precipitation by either mechanism. The similarity between the amyloid forming pathway when induced by either UV-B radiation or low pH suggests that it is the propensity for the C-terminal β-sandwich domain to form amyloid β-sheets that determines the misfolding pathway independent of the mechanism of denaturation. PMID:23957864

Photoaggregation of crystallins (main proteins of eye lens) under the effect of XeCl laser radiation

NASA Astrophysics Data System (ADS)

Soustov, Lev V.; Chelnokov, Evgeny V.; Bityurin, Nikita M.; Kiselev, A. L.; Nemov, V. V.; Sergeev, Yu. V.; Ostrovsky, Michail A.

2004-07-01

UV light is one of primary factors associated with cataract formation in the eye lens. α-, β-, γ-Crystallins maintain lens transparency, and damage to these proteins plays a major role in cataract formation. The effect of XeCl laser radiation (308 nm) on βL-crystallin solution is studied. The strong dependence of protein aggregation kinetics on both laser fluence (w) and repetition rate (F) is investigated. The kinetics features are similar to those of carbonic anhydrase photoaggregation studied previously.

Effect of Oral Lactoferrin on Cataract Surgery Induced Dry Eye: A Randomised Controlled Trial.

PubMed

Devendra, Jaya; Singh, Sneha

2015-10-01

Cataract surgery is one of the most frequently performed intra-ocular surgeries, of these manual Small Incision Cataract Surgery (SICS) is a time tested technique of cataract removal. Any corneal incisional surgery, including cataract surgery, can induce dry eye postoperatively. Various factors have been implicated, of which oneis the inflammation induced by the surgery. Lactoferrin, a glycoprotein present in tears is said to have anti-inflammatory effects, and promotes cell growth. It has been used orally in patients of immune mediated dry eye to alleviate symptoms. This study was aimed to evaluate the dry eyes induced by manual Small Incision Cataract Surgery, and the effect if any, of oral lactoferrin on the dry eyes. A single centre, prospective randomised controlled trial with a concurrent parallel design. The study was carried out on patients presenting in the OPD of Rohilkhand Medical College hospital for cataract surgery. Sixty four patients of cataract surgery were included in the study. Patients with pre-existing dry eyes, ocular disease or systemic disease predisposing to dry eyes were excluded from the study. The selected patients were assigned into two groups by simple randomisation-Control Group A-32 patients that did not receive oral lactoferrin postoperatively. Group B-32 patients that received oral lactoferrin 350 gm postoperatively from day 1 after SICS. All patients were operated for cataract and their pre and postoperative (on days 7, 14, 30 and 60) dry eye status was assessed using the mean tear film break-up time (tBUT) and Schirmer test 1 (ST 1) as the evaluating parameters. Subjective evaluation of dry eye was done using Ocular Surface Disease Index (OSDI) scoring. Data was analysed for 58 patients, as 6 did not complete the follow up. Unpaired t-test was used to calculate the p-values. There was a statistically significant difference between the tBUT values of the Control and Lactoferrin group from day 14 onwards. The tBUT of control group on day 60 was 7.86 (±0.86) seconds as compared to 13.9(± 0.99) seconds in the lactoferrin group. The Schirmer test 1 values also showed a statistically significant difference between the two groups- 15.86 (± 5.83) seconds in the control group versus 30.9 (±1.66) in the lactoferrin group on day 60. OSDI score showed 42.8% patients complaining of at least mild dry eye symptoms in the control group, as compared to 26.6% patients in the lactoferrin group on day 60. Small Incision Cataract Surgery induces dry eye postoperatively. Oral lactoferrin given postoperatively improves tear film status and dry eye after cataract surgery.

Ultraviolet radiation and the eye: an epidemiologic study.

PubMed Central

Taylor, H R

1989-01-01

Circumstantial evidence from biochemical, animal, and epidemiologic studies suggests an association between exposure to UV-B radiation (290 nm to 320 nm) and cataract. Such an association had not been proven because it had not been possible to quantify ocular UV-B exposure of individuals or to reliably grade the type and severity of cataract in field studies. We undertook an epidemiologic survey of cataract among 838 watermen who work on the Chesapeake Bay. Their individual ocular UV-B exposure was quantified for each year of life over the age of 16, on the basis of a detailed occupational history combined with laboratory and field measurements of ocular UV-B exposure. Cataracts were graded by both type and severity through clinical and photographic means. SMD changes were ascertained by fundal photography. A general medical history was taken to discover potentially confounding factors. This study showed that people with cortical lens opacities had a 21% higher UV-B exposure at each year of life than people without these opacities. A doubling in lifetime UV-B exposure led to a 60% increase in the risk of cortical cataract, and those with a high annual UV-B exposure increased their risk of cortical cataract over threefold. Corneal changes, namely pterygium and CDK, were also strongly associated with high UV-B exposure. No association was found between nuclear lens opacities or macular degeneration and UV-B exposure. This study also indicated several simple, practical measures, such as wearing spectacles or a hat, that effectively protect the eye from UV-B exposure. Thus it is easily within the power of individuals to protect their eyes from excessive UV-B exposure and reduce their risk of cortical cataract. A program of public education in this area could be a cost-effective means of reducing this important disease. PMID:2562534

The flavonoid, fisetin, inhibits UV radiation-induced oxidative stress and the activation of NF-kappaB and MAPK signaling in human lens epithelial cells.

PubMed

Yao, Ke; Zhang, Li; Zhang, Yidong; Ye, PanPan; Zhu, Ning

2008-01-01

Ultraviolet (UV) radiation-induced oxidative stress plays a significant role in the progression of cataracts. This study investigated the photoprotective effect of fisetin on UV radiation-induced oxidative stress in human lens epithelial cells and the possible molecular mechanism involved. SRA01/04 cells exposed to different doses of ultraviolet B (UVB) were cultured with various concentrations of fisetin and subsequently monitored for cell viability by the 4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT) assay. The effect of fisetin on the generation of reactive oxygen species (ROS) of SRA01/04 cells was determined by flow cytometry. Translocation of nuclear factor kappa-B (NF-kappaB) was examined by immunocytochemistry. Expression of NF-kappaB/P65, inhibiter kappa B (IkappaB), and mitogen activated protein kinase (MAPK) proteins were measured by western blot. Treatment of SRA01/04 cells with fisetin inhibited UVB-induced cell death and the generation of ROS. Fisetin inhibited UVB-induced activation and translocation of NF-kappaB/p65, which was mediated through an inhibition of the degradation and activation of IkappaB. Fisetin also inhibited UVB-induced phosphorylation of the p38 and c-Jun N-terminal kinase (JNK) proteins of the MAPK family at various time points studied. The flavonoid, fisetin, could be useful in attenuation of UV radiation-induced oxidative stress and the activation of NF-kappaB and MAPK signaling in human lens epithelial cells, which suggests that fisetin has a potential protective effect against cataractogenesis.

Increased risk of cataract development in WNIN-obese rats due to accumulation of intralenticular sorbitol.

PubMed

Reddy, Paduru Yadagiri; Giridharan, Nappan Veettil; Balakrishna, Nagalla; Validandi, Vakdevi; Pullakhandam, Raghu; Reddy, Geereddy Bhanuprakash

2013-05-01

Epidemiological studies have reported an association between obesity and increased incidence of ocular complications including cataract, yet the underlying biochemical and molecular mechanisms remained unclear. Previously we had demonstrated accumulation of sorbitol in the lens of obese rats (WNIN/Ob) and more so in a related strain with impaired glucose tolerance (WNIN/GR-Ob). However, only a few (15-20%) WNIN/Ob and WNIN/GR-Ob rats develop cataracts spontaneously with age. To gain further insights, we investigated the susceptibility of eye lens proteins of these obese rat strains to heat- and UV-induced aggregation in vitro, lens opacification upon glucose-mediated sorbitol accumulation ex vivo, and onset and progression of cataract was followed by galactose feeding and streptozotocin (STZ) injection. The results indicated increased susceptibility toward heat- or UV-induced aggregation of lens proteins in obese animals compared to their littermate lean controls. Further, in organ culture studies glucose-induced sorbitol accumulation was found to be higher and thus the lens opacification was faster in obese animals compared to their lean littermates. Also, the onset and progression of galactose- or STZ-induced cataractogenesis was faster in obese animals compared to lean control. These results together with our previous observations suggest that obesity status could lead to hyperaccumulation of sorbitol in eye lens, predisposing them to cataract, primarily by increasing their susceptibility to environmental and/or physiological factors. Further, intralenticular sorbitol accumulation beyond a threshold level could lead to cataract in WNIN/Ob and WNIN/GR-Ob rats. Copyright © 2013 International Union of Biochemistry and Molecular Biology, Inc.

Cataract after exposure to non-ionizing radiant energy.

PubMed Central

Zaret, M M; Snyder, W Z; Birenbaum, L

1976-01-01

The case histories of two individuals exposed to thermal radiation emitted from an electric oven and range were presented. In one patient, earlier exposure to medical diathermy appears to have initiated delayed or late-appearing, capsular cataracts. Instead of the anticipated slow progression, the cataractogenesis was accelerated following recent, repeated exposure to the intense, infrared radiation. In the other patient, exposed solely to infrared radiation, a chorioretinal lesion indistinguishable from the type characteristically secondary to repeated, thermal radiation was observed. More recently, the earliest sign of thermal radiation cataractogenesis, capsular opacification, has become evident. The widespread availability of radiant energy sources such as diathermy machines, microwave ovens, and electric ovens and ranges makes it imperative to examine carefully any possible hazards that may result from their use. With this in mind, radiant energy should be considered in the differential diagnosis of cataractogenesis. Images PMID:990233

Anti-Cataract Potential of Heliotropium indicum Linn on Galactose-Induced Cataract in Sprague-Dawley Rats.

PubMed

Kyei, Samuel; Koffuor, George A; Ramkissoon, Paul; Abu, Emmanuel K; Sarpong, Josephine F

2017-03-01

To evaluate the anti-cataract potential of an aqueous whole plant extract of Heliotropium indicum (HIE) on galactose-induced cataract in Sprague-Dawley rats. Cataract scores were recorded in 3-week-old Sprague-Dawley rats in which cataract was being induced by an oral administration of 1500 mgkg -1 galactose twice daily for 4 weeks, and concurrently being treated with 30, 100, or 300 mgkg -1 HIE daily over the induction period. Fasting blood glucose was monitored at weekly intervals. Changes in body weight as well as total lens protein, lens glutathione, and superoxide dismutase (SOD) were determined initially, and at the end of the experimental period. Crystalline lens weight-to-body-weight ratio was also determined for the various treatment groups at the end of the experimental period. Preliminary phytochemical screening, total antioxidant capacity, and reducing power assays were conducted on HIE. The 30 and 100 mgkg -1 HIE-treated rats recorded significantly lower (p ≤ 0.05-0.001) cataract scores (indicating very significant delays in cataractogenesis by the 3 rd and 4 th weeks of treatment) and blood glucose levels. Rats with delayed cataractogenesis also exhibited significant (p ≤ 0.05-0.001) weight gain, and reduction in lens weight. Total lens proteins glutathione and SOD levels in the crystalline lens were also significantly preserved (p ≤ 0.01-0.001). HIE showed substantial antioxidant capacity and reducing power. The aqueous whole plant extract of Heliotropium indicum delays cataractogenesis at an optimum dose of 30 mgkg -1 in Sprague-Dawley rats.

The risk of cataract in relation to metal arc welding.

PubMed

Slagor, Rebekka Michaelsen; La Cour, Morten; Bonde, Jens Peter

2016-09-01

There are indications that solar ultraviolet radiation (UVR) increases the risk of cataract, but there is only circumstantial evidence that metal welding, an important occupational source of UVR exposure, is a risk factor. The objective of this study is to unravel if metal welding increases the risk of cataract. We compared the risk of being diagnosed with cataract from 1987-2012 in a historic cohort of 4288 male metal arc welders against a reference group comprised of Danish skilled and unskilled male workers with similar age distribution. For the welders' cohort, information on welding was collected from questionnaires and, for both cohorts, information about cataract diagnosis and operation was gathered from Danish national registers. Using Cox regression analysis, the hazard ratio (HR) for cataract diagnosis and/or operation was calculated in the follow-up period adjusted for baseline data regarding age, diabetes, and social group. There were 266 welders and 29 007 referents with a diagnosis and/or operation for cataract. The unadjusted HR for cataract comparing ever-welders with referents was 1.07 [95% confidence interval (95% CI) 0.95-1.21] and the adjusted HR was 1.08 (95% CI 0.95-1.22). Age and diabetes were as expected strong risk factors. We found no increased risk of developing cataract among Danish metal welders who worked with arc welding from 1950-1985. This may be attributed to the effectiveness of personal safety equipment.

Late effects from particulate radiations in primate and rabbit tissues

NASA Astrophysics Data System (ADS)

Lett, J. T.; Cox, A. B.; Bergtold, D. S.; Lee, A. C.; Pickering, J. E.

Optic tissues in groups of New Zealand white rabbits were irradiated locally at different stages throughout the median life span of the species with a single dose (9 Gy) of 425 MeV/amu Ne ions (LET∞~30 keV/μm) and then inspected routinely for the progression of radiation cataracts. The level of early cataracts was found to be highest in the youngest group of animals irradiated (8 weeks old) but both the onset of late cataracts and loss of vision occurred earlier when animals were irradiated during the second half of the median life span. This age response can have serious implications in terms of space radiation hazards to man. Rhesus monkeys that had been subjected to whole-body skin irradiation (2.8 and 5.6 Gy) by 32 MeV protons (range in tissue ~ 1 cm) some twenty years previously were analysed for radiation damage by the propagation of skin fibroblasts in primary cultures. Such propagation from skin biopsies in MEM-α medium (serial cultivation) or in supplemented Ham's F-10 medium (cultivation without dilution) revealed late damage in the stem (precursor) cells of the skins of the animals. The proton fluxes employed in this experiment are representative of those occurring in major solar flares.

Lupeol, a pentacyclic triterpenoid isolated from Vernonia cinerea attenuate selenite induced cataract formation in Sprague Dawley rat pups.

PubMed

Asha, Radha; Gayathri Devi, V; Abraham, Annie

2016-02-05

This study investigated the inhibitory effects of active component isolated from flavonoid fraction of Vernonia cinerea (FVC), lupeol on selenite induced cataract formation. Previous reports suggest that phytochemicals or natural plant products retard the process of cataractogenesis by scavenging free oxygen radicals. Hence, the present study sought to assess the potential of lupeol on in vivo selenite induced cataract models. Lupeol, a pentacyclic triterpenoid, was isolated from the ethyl acetate fraction of methanolic extract of Vernonia cinerea, follows standard chromatographic techniques. Structural elucidation of the compound was carried out using (1)H NMR, (13)C NMR, Mass spectrometry together with other complementary techniques (UV and IR). From these, the isolated compound was identified as Lupeol (3'-hydroxylup-20(29)-ene). The antioxidant activity was comparatively studied using DPPH radical scavenging and FRAP assay. Lupeol exhibited higher DPPH radical scavenging activity as well as reducing power assay. In this study, cataract was induced by a single subcutaneous injection of sodium selenite (4 μg/g body weight) on rat pups. Lupeol was administered orally from 8th day upto 21st day at a concentration 25 μg/g body weight. Cataract was visualized on 16th day with the help of an ophthalmoscope and later on with the naked eye. On the 30th day, rats were euthanized by sodium pentothal injection, lenses were excised and the biochemical parameters such as activity of superoxide dismutase (SOD), catalase (CAT), Glutathione peroxidase (GPx), Glutathione reductase (GR), Glutathione-S-transferase (GST), Ca(2+) ATPase, glutathione content (GSH), reactive oxygen species (ROS), lipid peroxidation products (malondialdehyde) were estimated and found effective in the treatment of cataract by lupeol. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Standard-Fractionated Radiotherapy for Optic Nerve Sheath Meningioma: Visual Outcome Is Predicted by Mean Eye Dose

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abouaf, Lucie; Girard, Nicolas; Claude Bernard University, Lyon

2012-03-01

Purpose: Radiotherapy has shown its efficacy in controlling optic nerve sheath meningiomas (ONSM) tumor growth while allowing visual acuity to improve or stabilize. However, radiation-induced toxicity may ultimately jeopardize the functional benefit. The purpose of this study was to identify predictive factors of poor visual outcome in patients receiving radiotherapy for ONSM. Methods and Materials: We conducted an extensive analysis of 10 patients with ONSM with regard to clinical, radiologic, and dosimetric aspects. All patients were treated with conformal radiotherapy and subsequently underwent biannual neuroophthalmologic and imaging assessments. Pretreatment and posttreatment values of visual acuity and visual field were comparedmore » with Wilcoxon's signed rank test. Results: Visual acuity values significantly improved after radiotherapy. After a median follow-up time of 51 months, 6 patients had improved visual acuity, 4 patients had improved visual field, 1 patient was in stable condition, and 1 patient had deteriorated visual acuity and visual field. Tumor control rate was 100% at magnetic resonance imaging assessment. Visual acuity deterioration after radiotherapy was related to radiation-induced retinopathy in 2 patients and radiation-induced mature cataract in 1 patient. Study of radiotherapy parameters showed that the mean eye dose was significantly higher in those 3 patients who had deteriorated vision. Conclusions: Our study confirms that radiotherapy is efficient in treating ONSM. Long-term visual outcome may be compromised by radiation-induced side effects. Mean eye dose has to be considered as a limiting constraint in treatment planning.« less

A cost and policy analysis comparing immediate sequential cataract surgery and delayed sequential cataract surgery from the physician perspective in the United States.

PubMed

Neel, Sean T

2014-11-01

A cost analysis was performed to evaluate the effect on physicians in the United States of a transition from delayed sequential cataract surgery to immediate sequential cataract surgery. Financial and efficiency impacts of this change were evaluated to determine whether efficiency gains could offset potential reduced revenue. A cost analysis using Medicare cataract surgery volume estimates, Medicare 2012 physician cataract surgery reimbursement schedules, and estimates of potential additional office visit revenue comparing immediate sequential cataract surgery with delayed sequential cataract surgery for a single specialty ophthalmology practice in West Tennessee. This model should give an indication of the effect on physicians on a national basis. A single specialty ophthalmology practice in West Tennessee was found to have a cataract surgery revenue loss of $126,000, increased revenue from office visits of $34,449 to $106,271 (minimum and maximum offset methods), and a net loss of $19,900 to $91,700 (base case) with the conversion to immediate sequential cataract surgery. Physicians likely stand to lose financially, and this loss cannot be offset by increased patient visits under the current reimbursement system. This may result in physician resistance to converting to immediate sequential cataract surgery, gaming, and supplier-induced demand.

Biomarker for Space Radiation Risk: Painting Analysis of Chromosome Aberrations Induced by Energetic Heavy Ions in Human Cells

NASA Technical Reports Server (NTRS)

Hada, Megumi; George, Kerry; Cucinotta, Francis A.; Wu, Honglu

2007-01-01

Energetic heavy ions pose a great health risk to astronauts in extended ISS and future Lunar and Mars missions. High-LET heavy ions are particularly effective in causing various biological effects, including cell inactivation, genetic mutations, cataracts and cancer induction. Most of these biological endpoints are closely related to chromosomal damage, which can be utilized as a biomarker for radiation insults. Over the years, we have studied chromosomal damage in human fibroblast, epithelia and lymphocyte cells exposed in vitro to energetic charged particles generated at several accelerator facilities in the world. We have also studied chromosome aberrations in astronaut s peripheral blood lymphocytes before and after space flight. Various fluorescence in situ hybridization painting techniques have been used to identify from only the telomere region of the chromosome to every chromosome in a human cell. We will summarize the results of the investigations, and discuss the unique radiation signatures and biomarkers for space radiation exposure.

Late ophthalmological complications after total body irradiation in non-human primates

NASA Technical Reports Server (NTRS)

Niemer-Tucker, M. M.; Sterk, C. C.; de Wolff-Rouendaal, D.; Lee, A. C.; Lett, J. T.; Cox, A.; Emmanouilidis-van der Spek, K.; Davelaar, J.; Lambooy, A. C.; Mooy, C. M.;

Regulatory effect of acetyl-l-carnitine on expression of lenticular antioxidant and apoptotic genes in selenite-induced cataract.

PubMed

Elanchezhian, R; Sakthivel, M; Geraldine, P; Thomas, P A

2010-03-30

Differential expression of apoptotic genes has been demonstrated in selenite-induced cataract. Acetyl-l-carnitine (ALCAR) has been shown to prevent selenite cataractogenesis by maintaining lenticular antioxidant enzyme and redox system components at near normal levels and also by inhibiting lenticular calpain activity. The aim of the present experiment was to investigate the possibility that ALCAR also prevents selenite-induced cataractogenesis by regulating the expression of antioxidant (catalase) and apoptotic [caspase-3, early growth response protein-1 (EGR-1) and cytochrome c oxidase subunit I (COX-I)] genes. The experiment was conducted on 9-day-old Wistar rat pups, which were divided into normal, cataract-untreated and cataract-treated groups. Putative changes in gene expression in whole lenses removed from the rats were determined by measuring mRNA transcript levels of the four genes by RT-PCR analysis, using glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as an internal control. The expression of lenticular caspase-3 and EGR-1 genes appeared to be upregulated, as inferred by detecting increased mRNA transcript levels, while that of COX-I and catalase genes appeared to be downregulated (lowered mRNA transcript levels) in the lenses of cataract-untreated rats. However, in rats treated with ALCAR, the lenticular mRNA transcript levels were maintained at near normal (control) levels. These results suggest that ALCAR may prevent selenite-induced cataractogenesis by preventing abnormal expression of lenticular genes governing apoptosis.

The Claim of Anti-Cataract Potential of Heliotropium indicum: A Myth or Reality?

PubMed

Kyei, Samuel; Koffuor, George Asumeng; Ramkissoon, Paul; Afari, Clement; Asiamah, Emmanuel Akomanin

2015-12-01

Heliotropium indicum has several uses in traditional medicine attributable to its numerous bioactive compounds. It is used as a traditional remedy for cataracts in Ghana without any scientific verification. This study aimed at verifying the anti-cataract properties of an aqueous whole plant extract of H. indicum. The effect (cataract score) of 30, 100, and 300 mg kg(-1) extract (bid for 21 days, per os) on the development of 30 µmol kg(-1) sodium selenite-induced cataract in 10-day-old rat pups was investigated. Soluble lens proteins alpha A and alpha B crystallins, total lens protein, total lens glutathione, and aquaporin 0 in enucleated lens homogenates were determined spectrophotometrically using commercially available kits. Histopathological studies on the lenses were also performed. The 2,2-diphenyl-1-picrylhydrazyl scavenging effect and linoleic acid autoxidation (antioxidant properties) of the extract (0.1-3.0 mg ml(-1)), compared to n-propyl gallate, were ascertained using standard procedures. Cataract scores showed that the extract, at all dose levels, significantly alleviated selenite-induced cataracts (P ≤ 0.001). Markers of lens transparency (aquaporin 0, alpha A and B crystallins), as well as total lens proteins and lens glutathione levels, were significantly preserved (P ≤ 0.01-0.001). The extract exhibited activity relevant for scavenging free radicals and inhibition of lipid peroxidation. Epithelial and lens fiber integrity in the histopathological assessment were maintained with HIE treatment. The aqueous whole plant extract of H. indicum significantly inhibited the development of cataracts in rats via multiple mechanisms.

M-Band Analysis of Chromosome Aberrations in Human Epithelial Cells Induced By Low- and High-Let Radiations

NASA Technical Reports Server (NTRS)

Hada, M.; Gersey, B.; Saganti, P. B.; Wilkins, R.; Gonda, S. R.; Cucinotta, F. A.; Wu, H.

2007-01-01

Energetic primary and secondary particles pose a health risk to astronauts in extended ISS and future Lunar and Mars missions. High-LET radiation is much more effective than low-LET radiation in the induction of various biological effects, including cell inactivation, genetic mutations, cataracts and cancer. Most of these biological endpoints are closely correlated to chromosomal damage, which can be utilized as a biomarker for radiation insult. In this study, human epithelial cells were exposed in vitro to gamma rays, 1 GeV/nucleon Fe ions and secondary neutrons whose spectrum is similar to that measured inside the Space Station. Chromosomes were condensed using a premature chromosome condensation technique and chromosome aberrations were analyzed with the multi-color banding (mBAND) technique. With this technique, individually painted chromosomal bands on one chromosome allowed the identification of both interchromosomal (translocation to unpainted chromosomes) and intrachromosomal aberrations (inversions and deletions within a single painted chromosome). Results of the study confirmed the observation of higher incidence of inversions for high-LET irradiation. However, detailed analysis of the inversion type revealed that all of the three radiation types in the study induced a low incidence of simple inversions. Half of the inversions observed in the low-LET irradiated samples were accompanied by other types of intrachromosome aberrations, but few inversions were accompanied by interchromosome aberrations. In contrast, Fe ions induced a significant fraction of inversions that involved complex rearrangements of both the inter- and intrachromosome exchanges.

UV-radiation Induced Disruption of Dry-Cavities in Human γD-crystallin Results in Decreased Stability and Faster Unfolding

PubMed Central

Xia, Zhen; Yang, Zaixing; Huynh, Tien; King, Jonathan A.; Zhou, Ruhong

2013-01-01

Age-onset cataracts are believed to be expedited by the accumulation of UV-damaged human γD-crystallins in the eye lens. Here we show with molecular dynamics simulations that the stability of γD-crystallin is greatly reduced by the conversion of tryptophan to kynurenine due to UV-radiation, consistent with previous experimental evidences. Furthermore, our atomic-detailed results reveal that kynurenine attracts more waters and other polar sidechains due to its additional amino and carbonyl groups on the damaged tryptophan sidechain, thus breaching the integrity of nearby dry center regions formed by the two Greek key motifs in each domain. The damaged tryptophan residues cause large fluctuations in the Tyr-Trp-Tyr sandwich-like hydrophobic clusters, which in turn break crucial hydrogen-bonds bridging two β-strands in the Greek key motifs at the “tyrosine corner”. Our findings may provide new insights for understanding of the molecular mechanism of the initial stages of UV-induced cataractogenesis. PMID:23532089

Ultraviolet laser effects on the cornea

NASA Astrophysics Data System (ADS)

Zuclich, Joseph A.

1990-07-01

Ultraviolet radiation in the ambient environment or from artificial sources may pose both acute and chronic hazards to the skin and the ocular tissues. In general terrestrial conditions have evolved such that there are only narrow safety margins between ambient UV levels and exposure levels harmful to the human. Obvious examples of acute consequences ofUV overexposure are sunburn and snowblindness as well as analogous conditions induced by artificial sources such as the welder''s arc mercury vapor lamps and UV-emitting lasers. Further chronic UV exposure is strongly implicated as a causative agent in certain types of cataract and skin cancer. This presentation will summarize a number of specific cases where UV radiation affected the primate cornea. Data presented will include the action spectra for far- and near-UV induced ocular damage the pulsewidth and total energy dependencies of ocular thresholds studies of cumulative effects of repeated UV exposures and quantitative determinations of tissue repair or recovery rates. Depending on the exposure parameters utilized photochemical thermal or photoablative damage mechanisms may prevail. 1.

Mice heterozygous for the ATM gene are more sensitive to both X-ray and heavy ion exposure than are wildtypes

NASA Astrophysics Data System (ADS)

Worgul, B. V.; Smilenov, L.; Brenner, D. J.; Vazquez, M.; Hall, E. J.

Previous studies have shown that the eyes of ATM heterozygous mice exposed to low-LET radiation (X-rays) are significantly more susceptible to the development of cataracts than are those of wildtype mice. The findings, as well as others, run counter to the assumption underpinning current radiation safety guidelines, that individuals are all equally sensitive to the biological effects of radiation. A question, highly relevant to human space activities is whether or not, in similar fashion there may exist a genetic predisposition to high-LET radiation damage. Mice haplodeficient for the ATM gene and wildtypes were exposed to 325 mGy of 1 GeV/amu 56Fe ions at the AGS facility of Brookhaven National Laboratory. The fluence was equivalent to 1 ion per lens epithelial cell nuclear area. Controls consisted of irradiated wildtype as well as unirradiated wildtype and heterozygous mice. Prevalence analyses for stage 0.5-3.0 cataracts indicated that not only cataract onset but also progression were accelerated in the mice haplo-deficient for the ATM gene. The data show that heterozygosity for the ATM gene predisposes the eye to the cataractogenic influence of heavy ions and suggest that ATM heterozygotes in the human population may also be radiosensitive. This may have to be considered in the selection of individuals who will be exposed to both HZE particles and low-LET radiation as they may be predisposed to increased late normal tissue damage.

Relationship between cataracts and epilation in atomic bomb survivors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neriishi, Kazuo; Otake, Masanori; Kodama, Kazunori

1995-10-01

Among 1713 atomic bomb survivors who underwent ophthalmological examinations from 1963-1964, the risk of cataract formation per unit dose of radiation was significantly greater for those who reported hair loss of 67% or more after exposure (the epilation group) than for those who reported less or no hair loss (the no-epilation group) (P,0.01). Such an epilation effect has also been associated with leukemia mortality and the frequency of chromosome aberrations. Although this might be interpreted as indicating differential sensitivity to radiation between the epilation group and the no-epilation group, it could also be explained by imprecision in dose estimates. Wemore » have calculated that a 48% random error in DS86 dose estimates could be in accordance with the dose-response relationship for the prevalence of cataracts in the epilation group or the no-epilation group. Possible mechanisms for variations in radiosensitivity are discussed. 37 refs., 2 figs., 4 tabs.« less

Automatic Cataract Hardness Classification Ex Vivo by Ultrasound Techniques.

PubMed

Caixinha, Miguel; Santos, Mário; Santos, Jaime

2016-04-01

To demonstrate the feasibility of a new methodology for cataract hardness characterization and automatic classification using ultrasound techniques, different cataract degrees were induced in 210 porcine lenses. A 25-MHz ultrasound transducer was used to obtain acoustical parameters (velocity and attenuation) and backscattering signals. B-Scan and parametric Nakagami images were constructed. Ninety-seven parameters were extracted and subjected to a Principal Component Analysis. Bayes, K-Nearest-Neighbours, Fisher Linear Discriminant and Support Vector Machine (SVM) classifiers were used to automatically classify the different cataract severities. Statistically significant increases with cataract formation were found for velocity, attenuation, mean brightness intensity of the B-Scan images and mean Nakagami m parameter (p < 0.01). The four classifiers showed a good performance for healthy versus cataractous lenses (F-measure ≥ 92.68%), while for initial versus severe cataracts the SVM classifier showed the higher performance (90.62%). The results showed that ultrasound techniques can be used for non-invasive cataract hardness characterization and automatic classification. Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

p-Benzoquinone-induced aggregation and perturbation of structure and chaperone function of α-crystallin is a causative factor of cigarette smoke-related cataractogenesis.

PubMed

Chowdhury, Aritra; Choudhury, Aparajita; Chakraborty, Shruti; Ghosh, Arunava; Banerjee, Victor; Ganguly, Shinjini; Bhaduri, Gautam; Banerjee, Rajat; Das, Kalipada; Chatterjee, Indu B

2018-02-01

Cigarette smoking is a significant risk factor for cataract. However, the mechanism by which cigarette smoke (CS) causes cataract remains poorly understood. We had earlier shown that in CS-exposed guinea pig, p-benzoquinone (p-BQ) derived from CS in the lungs is carried by the circulatory system to distant organs and induces various smoke-related pathogeneses. Here, we observed that CS exposure caused accumulation of the p-BQ-protein adduct in the eye lens of guinea pigs. We also observed accumulation of the p-BQ-protein adduct in resected lens from human smokers with cataract. No such accumulation was observed in the lens of never smokers. p-BQ is a strong arylating agent that forms Michael adducts with serum albumin and haemoglobin resulting in alterations of structure and function. A major protein in the mammalian eye lens is αA-crystallin, which is a potent molecular chaperone. αA-crystallin plays a key role in maintaining the integrity and transparency of the lens. SDS-PAGE indicated that p-BQ induced aggregation of αA-crystallin. Various biophysical techniques including UV-vis spectroscopy, fluorescence spectroscopy, FT-IR, bis-ANS titration suggested a perturbation of structure and chaperone function of αA-crystallin upon p-BQ modification. Our results indicate that p-BQ is a causative agent involved in the modification of αA-crystallin and pathogenesis of CS-induced cataract. Our findings would educate public about the impacts of smoking on eye health and help to discourage them from smoking. The study might also help scientists to develop new drugs for the intervention of CS-induced cataract at an early stage. Copyright © 2017 Elsevier B.V. All rights reserved.

Non-destructive analysis of the conformational changes in human lens lipid and protein structures of the immature cataracts associated with glaucoma

NASA Astrophysics Data System (ADS)

Lin, Shan-Yang; Li, Mei-Jane; Liang, Run-Chu; Lee, Shui-Mei

1998-09-01

Previous study has supposed a possible mechanism of exacerbating cataract formation in cataractous human lens capsules induced by hypertension or glaucoma. To clarify the glaucoma-induced cataract formation of the eyes lens, changes in the human lens lipid and protein structures of immature cataractous patients with or without glaucoma were investigated. Two normal lenses, ten immature cataractous lenses without any complication and four immature cataractous lenses with glaucoma were used after surgical operation. Each de-capsulated human lens sample was sliced with a number 15 surgical blade. The intact nuclear lens regions were used for non-destructive analysis. The lens lipid and protein structures, as well as compositions of these lens samples, were determined using a Fourier transform infrared (FTIR) microspectroscopy with second-derivative, de-convolution and curve-fitting methods. The results indicate that the IR spectrum of glaucomatous lenses appeared as a shoulder only at 2853 cm -1, thus the composition of the symmetric CH 2 stretching band at 2853 (2852) cm -1 decreased more significantly in glaucomatous lens to only one half of that in normal and immature cataractous lenses. The composition of the asymmetric CH 3 stretching band at 2965 cm -1 for normal lens decreases markedly from 32 to 20% for immature cataractous lenses with or without glaucoma. The compositional ratio of component at 2965 cm -1 to component at 2928 (2930) cm -1 for normal lenses was about 0.702, and that ratio for cataractous lenses without glaucoma was 0.382 but for glaucomatous lenses was 0.377. The maximum peak position of amide I band for IR spectra of the normal lens, immature cataractous lenses without complications or glaucomatous lenses appeared respectively at 1632, 1630 or 1622 cm -1, assigned to β sheet structure. A marked difference in peak intensity of amide I band for the normal lenses and immature cataractous human lenses with or without glaucoma was observed. The peak intensity ratio of amide I /amide II (1632/1545 cm -1) for normal lenses was in the range of 2.20-2.33, whereas in the spectra of immature cataractous lenses without glaucoma this ratio (1630/1545 cm -1) was 1.28-1.41 but was 1.04-1.13 for glaucomatous lens in the intensity ratio of 1622/1545 cm -1. The intensity of the glycogen bands in the wavenumber region 1135-1076 and 1069-1032 cm -1 was found to increase for the immature cataractous lenses with or without glaucoma, as compared with the normal ones. The peaks ranging from 1633 to 1610 cm -1 assigned to β-sheet structure also exhibited a pronounced compositional difference, particularly in glaucomatous lenses. The human lens lipid and protein secondary structures were more affected by glaucoma. Higher protein side chains and reduced lipid content contributed predominantly to the CH stretching vibrations of normal lens structure, whereas high lipid content and less protein side chains dominated the CH stretching vibrations of cataractous lenses with or without glaucoma. Decrease α-helix and random coil structures but enhanced β-sheet structure in the immature cataractous human lens induced by glaucoma might result from the formation of intermolecular hydrogen-bonding insoluble protein aggregates that modify the secondary structure of protein in lenses.

Dose conversion coefficients for monoenergetic electrons incident on a realistic human eye model with different lens cell populations.

PubMed

Nogueira, P; Zankl, M; Schlattl, H; Vaz, P

2011-11-07

The radiation-induced posterior subcapsular cataract has long been generally accepted to be a deterministic effect that does not occur at doses below a threshold of at least 2 Gy. Recent epidemiological studies indicate that the threshold for cataract induction may be much lower or that there may be no threshold at all. A thorough study of this subject requires more accurate dose estimates for the eye lens than those available in ICRP Publication 74. Eye lens absorbed dose per unit fluence conversion coefficients for electron irradiation were calculated using a geometrical model of the eye that takes into account different cell populations of the lens epithelium, together with the MCNPX Monte Carlo radiation transport code package. For the cell population most sensitive to ionizing radiation-the germinative cells-absorbed dose per unit fluence conversion coefficients were determined that are up to a factor of 4.8 higher than the mean eye lens absorbed dose conversion coefficients for electron energies below 2 MeV. Comparison of the results with previously published values for a slightly different eye model showed generally good agreement for all electron energies. Finally, the influence of individual anatomical variability was quantified by positioning the lens at various depths below the cornea. A depth difference of 2 mm between the shallowest and the deepest location of the germinative zone can lead to a difference between the resulting absorbed doses of up to nearly a factor of 5000 for electron energy of 0.7 MeV.

Effect of standardized fruit extract of Luffa cylindrica on oxidative stress markers in hydrogen peroxide induced cataract.

PubMed

Dubey, Suchita; Saha, Sudipta; Kaithwas, Gaurav; Saraf, Shubhini A

2015-01-01

The ability of Luffa cylindrica Roem fruit extract (LCE) to modulate biochemical parameters was investigated by in vitro studies for its role in hydrogen peroxide induced cataract on isolated goat lenses which were incubated for 72 h at 37°C. Test groups contained 5, 10, 15, 20, 25, and 30 µg/ml of LCE along with 1 ml of H2O2 (0.5 mM) as cataract inducer. Lenses were examined for morphological variation and transparency periodically during the incubation. Biochemical parameters such as superoxide dismutase (SOD), reduced glutathione (GSH), total protein content (TPC), and malondialdehyde (MDA) were estimated. SOD, GSH, and TPC levels were found to increase proportionally with the concentration of LCE. However, MDA levels were found to be inversely proportional to the concentration of LCE. Opacity was graded as per "lens opacities classification system III." Morphological examination suggested that LCE (25 µg/ml) maintained a vision for 44 h. No lens in LCE dose groups developed dense nuclear opacity after 24 h as opposed to 80% in negative control. The results suggest that LCE can delay the onset and/or prevent the progression of cataract which can be attributed to the presence of adequate phenolics, flavonoids, and Vitamin A and its high nutritional value. This preliminary study can be further synergized by testing LCE against other in vivo and in vitro models of cataract.

Ultraviolet radiation cataract: dose dependence

NASA Astrophysics Data System (ADS)

Soderberg, Per G.; Loefgren, Stefan

1994-07-01

Current safety limits for cataract development after acute exposure to ultraviolet radiation (UVR) are based on experiments analyzing experimental data with a quantal, effect-no effect, dose-response model. The present study showed that intensity of forward light scattering is better described with a continuous dose-response model. It was found that 3, 30 and 300 kJ/m2UVR300nm induces increased light scattering within 6 h. For all three doses the intensity of forward light scattering was constant after 6 h. The intensity of forward light scattering was proportional to the log dose of UVR300nm. There was a slight increase of the intensity of forward light scattering on the contralateral side in animals that received 300 kJ/m2. Altogether 72 Sprague-Dawley male rats were included. Half of the rats were exposed in vivo on one side to UVR300nm. The other half was kept as a control group, receiving the same treatment as exposed rats but without delivery of UVR300nm to the eye. Subgroups of the rats received either of the three doses. Rats were sacrificed at varying intervals after the exposure. The lenses were extracted and the forward light scattering was estimated. It is concluded that intensity of forward light scattering in the lens after exposure to UVR300nm should be described with a continuous dose-reponse model.

[Eye lens radiation exposure during ureteroscopy with and without a face protection shield: Investigations on a phantom model].

PubMed

Zöller, G; Figel, M; Denk, J; Schulz, K; Sabo, A

2016-03-01

Eye lens radiation exposure during radiologically-guided endoscopic procedures may result in radiation-induced cataracts; therefore, we investigated the ocular radiation exposure during ureteroscopy on a phantom model. Using an Alderson phantom model and eye lens dosimeters, we measured the ocular radiation exposure depending on the number of X-ray images and on the duration of fluoroscopic imaging. The measurements were done with and without using a face protection shield. We could demonstrate that a significant ocular radiation exposure can occur, depending on the number of X-ray images and on the duration time of fluoroscopy. Eye lens doses up to 0.025 mSv were recorded even using modern digital X-ray systems. Using face protection shields this ocular radiation exposure can be reduced to a minimum. The International Commission on Radiological Protection (ICRP) recommendations of a mean eye lens dosage of 20 mSv/year may be exceeded during repeated ureteroscopy by a high volume surgeon. Using a face protection shield, the eye lens dose during ureteroscopy could be reduced to a minimum in a phantom model. Further investigations will show whether these results can be transferred to real life ureteroscopic procedures.

Radiation-associated lens changes in the cardiac catheterization laboratory: Results from the IC-CATARACT (CATaracts Attributed to RAdiation in the CaTh lab) study.

PubMed

Karatasakis, Aris; Brilakis, Harilaos S; Danek, Barbara A; Karacsonyi, Judit; Martinez-Parachini, Jose Roberto; Nguyen-Trong, Phuong-Khanh J; Alame, Aya J; Roesle, Michele K; Rangan, Bavana V; Rosenfield, Kenneth; Mehran, Roxana; Mahmud, Ehtisham; Chambers, Charles E; Banerjee, Subhash; Brilakis, Emmanouil S

2018-03-01

To examine the relationship between occupational exposure to ionizing radiation and the prevalence of lens changes in interventional cardiologists (ICs) and catheterization laboratory ("cath-lab") staff. Exposure to ionizing radiation is associated with the development of lens opacities. ICs and cath-lab staff can receive high doses of ionizing radiation without protection, and may thus be at risk for lens opacity formation. We conducted a cross-sectional study at an interventional cardiology conference. Study participants completed a questionnaire pertaining to occupational exposure to radiation and potential confounders for the development of cataracts, followed by slit-lamp examination and grading of lens findings. A total of 117 attendees participated in the study, including 99 (85%; 49 ± 11 years-old; 82% male) with occupational exposure to ionizing radiation and 18 (15%; 39 ± 12 years-old; 61% male) unexposed controls. The prevalence of overall cortical and posterior subcapsular lens changes (including subclinical findings) was higher in exposed participants compared with controls (47 vs. 17%, P = 0.015). Occupational exposure and age over 60 were independent predictors of lens changes (odds ratio [95% CI]: 6.07 [1.38-43.45] and 7.72 [1.60-43.34], respectively). The prevalence of frank opacities was low and similar between the two groups (14 vs. 6%, P = 0.461). Most lens findings consisted of subclinical changes in the periphery of the lens without impact on visual acuity. Compared with unexposed controls, ICs and cath-lab staff had a higher prevalence of lens changes that may be attributable to ionizing radiation exposure. While most of these changes were subclinical, they are important due to the potential to progress to clinical symptoms, highlighting the importance of minimizing staff radiation exposure. © 2017 Wiley Periodicals, Inc.

Effects of calcium dobesilate on Nrf2, Keap1 and HO-1 in the lenses of D-galactose-induced cataracts in rats

PubMed Central

Sun, Jinfeng; Wang, Bin; Hao, Youjuan; Yang, Xueli

2018-01-01

This study investigated the effects of calcium dobesilate on Nrf2, Keap1 and HO-1 in the lenses of D-galactose-induced cataracts in rats. Thirty Sprague-Dawley rats were randomly divided into three groups: a blank control group, a model control group and a model administration group. A normal diet was given to the rats in the blank control group and the rats with D-galactose-induced cataracts of the model control group. Calcium dobesilate was also given to the rats with D-galactose-induced cataracts of the model administration group. A slit lamp microscope was used to check the degree of lens opacity. RT-PCR and western blot analysis were used to detect the mRNA and protein expression of Nrf2, Keap1 and HO-1 in the lenses of the three groups. There was a significant difference in the degree of lens opacity among the three groups (P<0.05). The model control group was the most turbid of the three groups, followed by the model administration group. Moreover, the mRNA and protein expression of Nrf2, Keap1 and HO-1 in the lenses of the three groups were also significantly different (P<0.05). The mRNA levels of Nrf2 and HO-1 were the highest in the model control group, followed by the model administration group, and were the lowest in the blank control group. However, the mRNA expression level of Keap1 among the three groups had an opposite trend. In conclusion, calcium dobesilate can effectively increase the levels of Nrf2 and HO-1 in the lenses of diabetic cataract rats and inhibit the level of Keap1. Therefore, the therapeutic effect of calcium dobesilate against cataracts is related to the improvement of the Nrf2-Keap1 signaling pathway. PMID:29399076

Eye Lens Radiation Exposure in Greek Interventional Cardiology Article.

PubMed

Thrapsanioti, Zoi; Askounis, Panagiotis; Datseris, Ioannis; Diamanti, Ramza Anastasia; Papathanasiou, Miltiadis; Carinou, Eleftheria

2017-07-01

The lens of the eye is one of the radiosensitive tissues of the human body; if exposed to ionizing radiation can develop radiation-induced cataract at early ages. This study was held in Greece and included 44 Interventional Cardiologists (ICs) and an unexposed to radiation control group of 22 persons. Of the note, 26 ICs and the unexposed individuals underwent special eye examinations. The detected lens opacities were classified according to LOCS III protocol. Additionally, the lens doses of the ICs were measured using eye lens dosemeters. The mean dose to the lenses of the ICs per month was 0.83 ± 0.59 mSv for the left and 0.35 ± 0.38 mSv for the right eye, while the annual doses ranged between 0.7 and 11 mSv. Regarding the lens opacities, the two groups did not differ significantly in the prevalence of either nuclear or cortical lens opacities, whereas four ICs were detected with early stage subcapsular sclerosis. Though no statistically difference was observed in the cohort, the measured doses indicate that the eye doses received from the ICs can be significant. To minimize the radiation-induced risk at the eye lenses, the use of protective equipment and appropriate training on this issue is highly recommended. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Senile cataracts and myopia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Belkin, M.; Jacobs, D.R.; Jackson, S.M.

1982-01-01

A retrospective survey of 32 persons with myopia and 38 persons with emmetropia who had been operated on at two US Army hospitals on the California coast showed that the persons with myopia who had worn eyeglasses for at least 20 years underwent cataract extraction at a significantly (P less than .00005) older age than the persons with emmetropia (median age at the time of the operation was 70 years, compared with 64 years). These results support the theory that some protection against solar ultraviolet radiation is offered the eyes by eye wear worn continuously and that solar ultraviolet radiationmore » may be a contributing factor in the formation of human senile cataracts.« less

Site specific oxidation of amino acid residues in rat lens γ-crystallin induced by low-dose γ-irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Ingu; Saito, Takeshi; Research Reactor Institute, Kyoto University, Kumatori, Osaka 590-0494

Although cataracts are a well-known age-related disease, the mechanism of their formation is not well understood. It is currently thought that eye lens proteins become abnormally aggregated, initially causing clumping that scatters the light and interferes with focusing on the retina, and ultimately resulting in a cataract. The abnormal aggregation of lens proteins is considered to be triggered by various post-translational modifications, such as oxidation, deamidation, truncation and isomerization, that occur during the aging process. Such modifications, which are also generated by free radical and reactive oxygen species derived from γ-irradiation, decrease crystallin solubility and lens transparency, and ultimately leadmore » to the development of a cataract. In this study, we irradiated young rat lenses with low-dose γ-rays and extracted the water-soluble and insoluble protein fractions. The water-soluble and water-insoluble lens proteins were digested with trypsin, and the resulting peptides were analyzed by LC-MS. Specific oxidation sites of methionine, cysteine and tryptophan in rat water-soluble and -insoluble γE and γF-crystallin were determined by one-shot analysis. The oxidation sites in rat γE and γF-crystallin resemble those previously identified in γC and γD-crystallin from human age-related cataracts. Our study on modifications of crystallins induced by ionizing irradiation may provide useful information relevant to human senile cataract formation. - Highlights: • Low-dose γ-rays induced oxidation at specific residues in γE- and γF-crystallin. • The number of oxidation sites was higher in insoluble than soluble crystallins. • γ-Irradiation closely mimics the oxidation that occur in senile human cataracts.« less

Looking into future: challenges in radiation protection in medicine.

PubMed

Rehani, M M

2015-07-01

Radiation protection in medicine is becoming more and more important with increasing wider use of X-rays, documentation of effects besides the potential for long-term carcinogenic effects. With computed tomography (CT) likely to become sub-mSv in coming years, positron emission tomography (PET), single photon emission computed tomography (SPECT) and some of the nuclear medical examination will become focus of attraction as high-dose examinations, even though they are less-frequent ones. Clarity will be needed on radiation effects at levels of radiation doses encountered in a couple of CT scans and if effects are really cumulative. There is challenge to develop radiation metrics that can be used as easily as units of temperature and length and avoidance of multiple meaning of a single dose metric. Other challenges include development of biological indicators of radiation dose, transition from dose to a representative phantom to dose to individual patient, system for tracking of radiation exposure history of patient, avoidance of radiation-induced skin injury in patients and radiation cataract in staff, cutting down inappropriate referrals for radiological examinations, confidence building in patient and patient safety in radiotherapy. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Light-focusing human micro-lenses generated from pluripotent stem cells model lens development and drug-induced cataract in vitro

PubMed Central

Murphy, Patricia; Kabir, Md Humayun; Srivastava, Tarini; Mason, Michele E.; Dewi, Chitra U.; Lim, Seakcheng; Yang, Andrian; Djordjevic, Djordje; Killingsworth, Murray C.; Ho, Joshua W. K.; Harman, David G.

2018-01-01

ABSTRACT Cataracts cause vision loss and blindness by impairing the ability of the ocular lens to focus light onto the retina. Various cataract risk factors have been identified, including drug treatments, age, smoking and diabetes. However, the molecular events responsible for these different forms of cataract are ill-defined, and the advent of modern cataract surgery in the 1960s virtually eliminated access to human lenses for research. Here, we demonstrate large-scale production of light-focusing human micro-lenses from spheroidal masses of human lens epithelial cells purified from differentiating pluripotent stem cells. The purified lens cells and micro-lenses display similar morphology, cellular arrangement, mRNA expression and protein expression to human lens cells and lenses. Exposing the micro-lenses to the emergent cystic fibrosis drug Vx-770 reduces micro-lens transparency and focusing ability. These human micro-lenses provide a powerful and large-scale platform for defining molecular disease mechanisms caused by cataract risk factors, for anti-cataract drug screening and for clinically relevant toxicity assays. PMID:29217756

Light-focusing human micro-lenses generated from pluripotent stem cells model lens development and drug-induced cataract in vitro.

PubMed

Murphy, Patricia; Kabir, Md Humayun; Srivastava, Tarini; Mason, Michele E; Dewi, Chitra U; Lim, Seakcheng; Yang, Andrian; Djordjevic, Djordje; Killingsworth, Murray C; Ho, Joshua W K; Harman, David G; O'Connor, Michael D

2018-01-09

Cataracts cause vision loss and blindness by impairing the ability of the ocular lens to focus light onto the retina. Various cataract risk factors have been identified, including drug treatments, age, smoking and diabetes. However, the molecular events responsible for these different forms of cataract are ill-defined, and the advent of modern cataract surgery in the 1960s virtually eliminated access to human lenses for research. Here, we demonstrate large-scale production of light-focusing human micro-lenses from spheroidal masses of human lens epithelial cells purified from differentiating pluripotent stem cells. The purified lens cells and micro-lenses display similar morphology, cellular arrangement, mRNA expression and protein expression to human lens cells and lenses. Exposing the micro-lenses to the emergent cystic fibrosis drug Vx-770 reduces micro-lens transparency and focusing ability. These human micro-lenses provide a powerful and large-scale platform for defining molecular disease mechanisms caused by cataract risk factors, for anti-cataract drug screening and for clinically relevant toxicity assays. © 2018. Published by The Company of Biologists Ltd.

[Radiation protection in interventional radiology].

PubMed

Adamus, R; Loose, R; Wucherer, M; Uder, M; Galster, M

2016-03-01

The application of ionizing radiation in medicine seems to be a safe procedure for patients as well as for occupational exposition to personnel. The developments in interventional radiology with fluoroscopy and dose-intensive interventions require intensified radiation protection. It is recommended that all available tools should be used for this purpose. Besides the options for instruments, x‑ray protection at the intervention table must be intensively practiced with lead aprons and mounted lead glass. A special focus on eye protection to prevent cataracts is also recommended. The development of cataracts might no longer be deterministic, as confirmed by new data; therefore, the International Commission on Radiological Protection (ICRP) has lowered the threshold dose value for eyes from 150 mSv/year to 20 mSv/year. Measurements show that the new values can be achieved by applying all X‑ray protection measures plus lead-containing eyeglasses.

Laser Raman Spectroscopy of Ultraviolet-Induced Cataracts in Rabbits and Monkeys.

DTIC Science & Technology

1979-12-01

ILTRAVIOLETINHUCED CATARACTS SIN RABBITS AND MONKEYS Dwaine M. Thomas, Ph.D. ,KennethL. Schepler, Captain, USAF December 1979 Final Report for Period...3AMAN VECTROSCOPY OF .JLTRAV IOLET;NDUCED) POR U77 -FbR7 WATARACTS IN RABBITS AND MONKEYS .0 R. O,;4MIE V 111___ 2= _ 7. AUTHOR(*) S. CONTRACT OR GRANT...cataracts ABSTRACT (Continue on rev’erse side if necessary art# identify hV block numb~er) he Raman spectrl .of aormal rabbit’ana monkey lenses have been

Acute microwave irradiation and cataract formation in rabbits and monkeys.

PubMed

Kramar, P; Harris, C; Emery, A F; Guy, A W

1978-09-01

Rabbits and monkeys were irradiated in the near field of a cavity-backed 2450 MHz resonant slot radiator, to determine the cataractogenic threshold. Rabbits developed cataracts at incident "apparent" power densities of 180 mW/cm2 (E2/120 pi, where E=rms/electric field strength). Monkeys sustained facial burns, but no lens damage, even at incident "apparent" power densities of 500 mW/cm2. These results were substantiated by computer thermal models.

Solar radiation and human health

NASA Astrophysics Data System (ADS)

Juzeniene, Asta; Brekke, Pål; Dahlback, Arne; Andersson-Engels, Stefan; Reichrath, Jörg; Moan, Kristin; Holick, Michael F.; Grant, William B.; Moan, Johan

2011-06-01

The Sun has played a major role in the development of life on Earth. In Western culture, people are warned against Sun exposure because of its adverse effects: erythema, photoimmunosuppression, photoageing, photocarcinogenesis, cataracts and photokeratitis. However, Sun exposure is also beneficial, since moderate doses give beneficial physiological effects: vitamin D synthesis, reduction of blood pressure and mental health. Shortage of Sun exposure may be even more dangerous to human health than excessive exposure. Avoiding Sun exposure leads to vitamin D deficiency which is associated not only with rickets and osteomalacia, but also with increased risk of cardiovascular disease, multiple sclerosis, rheumatoid arthritis, diabetes, influenza, many types of cancer and adverse pregnancy outcomes. Solar radiation induces nitric oxide release in tissue and immediate pigment darkening which certainly play important roles, although these are still unknown. Action spectra relevant for health are described. We will also review what is known about spectral and intensity variations of terrestrial solar radiation as well as its penetration through the atmosphere and into human skin and tissue.

The effect of corneal anterior surface eccentricity on astigmatism after cataract surgery.

PubMed

Park, Choul Yong; Chuck, Roy S; Channa, Prabjot; Lim, Chi-Yeon; Ahn, Byung-Jin

2011-01-01

To evaluate the effect of cornea eccentricity on induced astigmatism after cataract surgery. The study included 125 eyes of 87 patients. Preoperative corneal astigmatism, pachymetry, and eccentricity were measured. During cataract surgery, the location of the main incision (2.8-mm clear corneal) was selected to be either superior, superior-nasal, superior-temporal, nasal, or temporal to decrease the preexisting corneal astigmatism. Aspheric intraocular lenses were implanted. Keratometry and manifest refraction were recorded 6 months after surgery. Astigmatism was calculated using vector subtraction software. Three parameters significantly affected postoperative astigmatism: preoperative amount of corneal astigmatism, eccentricity of anterior cornea, and location of the main incision. The mean surgically induced astigmatism (SIA) was calculated to be: superior = 0.82 diopters (D), superior-nasal = 0.50 D, superior-temporal = 0.63 D, temporal = 0.45 D, and nasal = 0.55 D. Superior incision induced the greatest SIA and temporal incision induced the smallest SIA. The eccentricity of anterior cornea showed significantly positive correlation with the amount of SIA (P < .001). The preoperative corneal cylinder power showed significantly positive correlation with the amount of SIA (P < .001). Postoperative astigmatism was affected by various factors in cataract surgery. The greatest postoperative astigmatism is expected in corneas with high anterior eccentricity, high preoperative corneal astigmatism, and superior location of the main incision. Copyright 2011, SLACK Incorporated.

EVALUATION OF EYE LENS DOSE TO WORKERS IN THE STEAM GENERATOR AT THE KOREAN OPTIMIZED POWER REACTOR 1000.

PubMed

Maeng, Sung Jun; Kim, Jinhwan; Cho, Gyuseong

2018-03-15

ICRP (2011) revised the dose limit to the eye lens to 20 mSv/y based on a recent epidemiological study of radiation-induced cataracts. Maintenance of steam generators at nuclear power plants is one of the highest radiation-associated tasks within a non-uniform radiation field. This study aims to evaluate eye lens doses in the steam generators of the Korean OPR1000 design. The source term was characterized based on the CRUD-specific activity, and both the eye lens dose and organ dose were simulated using MCNP6 combined with an ICRP voxel phantom and a mesh phantom, respectively. The eye lens dose was determined to be 5.39E-02-9.43E-02 Sv/h, with a negligible effect by beta particles. As the effective dose was found to be 0.81-1.21 times the lens equivalent dose depending on the phantom angles, the former can be used to estimate the lens dose in the SG of the OPR1000 for radiation monitoring purposes.

Role of pirenoxine in the effects of catalin on in vitro ultraviolet-induced lens protein turbidity and selenite-induced cataractogenesis in vivo

PubMed Central

Hu, Chao-Chien; Liao, Jiahn-Haur; Hsu, Kuang-Yang; Lin, I-Lin; Tsai, Ming-Hsuan; Wu, Wen-Hsin; Wei, Tzu-Tang; Huang, Yi-Shiang; Chiu, Shih-Jiuan; Chen, Hsiang-Yin; Wu, Shih-Hsiung

2011-01-01

Purpose In this study, we investigated the biochemical pharmacology of pirenoxine (PRX) and catalin under in vitro selenite/calcium- and ultraviolet (UV)-induced lens protein turbidity challenges. The systemic effects of catalin were determined using a selenite-induced cataractogenesis rat model. Methods In vitro cataractogenesis assay systems (including UVB/C photo-oxidation of lens crystallins, calpain-induced proteolysis, and selenite/calcium-induced turbidity of lens crystallin solutions) were used to screen the activity of PRX and catalin eye drop solutions. Turbidity was identified as the optical density measured using spectroscopy at 405 nm. We also determined the in vivo effects of catalin on cataract severity in a selenite-induced cataract rat model. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS–PAGE) was applied to analyze the integrity of crystallin samples. Results PRX at 1,000 μM significantly delayed UVC-induced turbidity formation compared to controls after 4 h of UVC exposure (p<0.05), but not in groups incubated with PRX concentrations of <1,000 μM. Results were further confirmed by SDS–PAGE. The absolute γ-crystallin turbidity induced by 4 h of UVC exposure was ameliorated in the presence of catalin equivalent to 1~100 μM PRX in a concentration-dependent manner. Samples with catalin-formulated vehicle only (CataV) and those containing PRX equivalent to 100 μM had a similar protective effect after 4 h of UVC exposure compared to the controls (p<0.05). PRX at 0.03, 0.1, and 0.3 μM significantly delayed 10 mM selenite- and calcium-induced turbidity formation compared to controls on days 0~4 (p<0.05). Catalin (equivalent to 32, 80, and 100 μM PRX) had an initial protective effect against selenite-induced lens protein turbidity on day 1 (p<0.05). Subcutaneous pretreatment with catalin (5 mg/kg) also statistically decreased the mean cataract scores in selenite-induced cataract rats on post-induction day 3 compared to the controls (1.3±0.2 versus 2.4±0.4; p<0.05). However, catalin (equivalent to up to 100 μM PRX) did not inhibit calpain-induced proteolysis activated by calcium, and neither did 100 μM PRX. Conclusions PRX at micromolar levels ameliorated selenite- and calcium-induced lens protein turbidity but required millimolar levels to protect against UVC irradiation. The observed inhibition of UVC-induced turbidity of lens crystallins by catalin at micromolar concentrations may have been a result of the catalin-formulated vehicle. Transient protection by catalin against selenite-induced turbidity of crystallin solutions in vitro was supported by the ameliorated cataract scores in the early stage of cataractogenesis in vivo by subcutaneously administered catalin. PRX could not inhibit calpain-induced proteolysis activated by calcium or catalin itself, and may be detrimental to crystallins under UVB exposure. Further studies on formulation modifications of catalin and recommended doses of PRX to optimize clinical efficacy by cataract type are warranted. PMID:21850160

Role of pirenoxine in the effects of catalin on in vitro ultraviolet-induced lens protein turbidity and selenite-induced cataractogenesis in vivo.

PubMed

Hu, Chao-Chien; Liao, Jiahn-Haur; Hsu, Kuang-Yang; Lin, I-Lin; Tsai, Ming-Hsuan; Wu, Wen-Hsin; Wei, Tzu-Tang; Huang, Yi-Shiang; Chiu, Shih-Jiuan; Chen, Hsiang-Yin; Wu, Shih-Hsiung; Wu, Tzu-Hua

2011-01-01

In this study, we investigated the biochemical pharmacology of pirenoxine (PRX) and catalin under in vitro selenite/calcium- and ultraviolet (UV)-induced lens protein turbidity challenges. The systemic effects of catalin were determined using a selenite-induced cataractogenesis rat model. In vitro cataractogenesis assay systems (including UVB/C photo-oxidation of lens crystallins, calpain-induced proteolysis, and selenite/calcium-induced turbidity of lens crystallin solutions) were used to screen the activity of PRX and catalin eye drop solutions. Turbidity was identified as the optical density measured using spectroscopy at 405 nm. We also determined the in vivo effects of catalin on cataract severity in a selenite-induced cataract rat model. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was applied to analyze the integrity of crystallin samples. PRX at 1,000 μM significantly delayed UVC-induced turbidity formation compared to controls after 4 h of UVC exposure (p<0.05), but not in groups incubated with PRX concentrations of <1,000 μM. Results were further confirmed by SDS-PAGE. The absolute γ-crystallin turbidity induced by 4 h of UVC exposure was ameliorated in the presence of catalin equivalent to 1~100 μM PRX in a concentration-dependent manner. Samples with catalin-formulated vehicle only (CataV) and those containing PRX equivalent to 100 μM had a similar protective effect after 4 h of UVC exposure compared to the controls (p<0.05). PRX at 0.03, 0.1, and 0.3 μM significantly delayed 10 mM selenite- and calcium-induced turbidity formation compared to controls on days 0~4 (p<0.05). Catalin (equivalent to 32, 80, and 100 μM PRX) had an initial protective effect against selenite-induced lens protein turbidity on day 1 (p<0.05). Subcutaneous pretreatment with catalin (5 mg/kg) also statistically decreased the mean cataract scores in selenite-induced cataract rats on post-induction day 3 compared to the controls (1.3±0.2 versus 2.4±0.4; p<0.05). However, catalin (equivalent to up to 100 μM PRX) did not inhibit calpain-induced proteolysis activated by calcium, and neither did 100 μM PRX. PRX at micromolar levels ameliorated selenite- and calcium-induced lens protein turbidity but required millimolar levels to protect against UVC irradiation. The observed inhibition of UVC-induced turbidity of lens crystallins by catalin at micromolar concentrations may have been a result of the catalin-formulated vehicle. Transient protection by catalin against selenite-induced turbidity of crystallin solutions in vitro was supported by the ameliorated cataract scores in the early stage of cataractogenesis in vivo by subcutaneously administered catalin. PRX could not inhibit calpain-induced proteolysis activated by calcium or catalin itself, and may be detrimental to crystallins under UVB exposure. Further studies on formulation modifications of catalin and recommended doses of PRX to optimize clinical efficacy by cataract type are warranted.

Occupational radiation exposure in nuclear medicine department in Kuwait

NASA Astrophysics Data System (ADS)

Alnaaimi, M.; Alkhorayef, M.; Omar, M.; Abughaith, N.; Alduaij, M.; Salahudin, T.; Alkandri, F.; Sulieman, A.; Bradley, D. A.

2017-11-01

Ionizing radiation exposure is associated with eye lens opacities and cataracts. Radiation workers with heavy workloads and poor protection measures are at risk for vision impairment or cataracts if suitable protection measures are not implemented. The aim of this study was to measure and evaluate the occupational radiation exposure in a nuclear medicine (NM) department. The annual average effective doses (Hp[10] and Hp[0.07]) were measured using calibrated thermos-luminescent dosimeters (TLDs; MCP-N [LiF:Mg,Cu,P]). Five categories of staff (hot lab staff, PET physicians, NM physicians, technologists, and nurses) were included. The average annual eye dose (Hp[3]) for NM staff, based on measurements for a typical yearly workload of >7000 patients, was 4.5 mSv. The annual whole body radiation (Hp[10]) and skin doses (Hp[0.07]) were 4.0 and 120 mSv, respectively. The measured Hp(3), Hp(10), and Hp(0.07) doses for all NM staff categories were below the dose limits described in ICRP 2014 in light of the current practice. The results provide baseline data for staff exposure in NM in Kuwait. Radiation dose optimization measures are recommended to reduce NM staff exposure to its minimal value.

Measuring aniseikonia using scattering filters to simulate cataract

NASA Astrophysics Data System (ADS)

Wilson, Jason

2011-12-01

The relationship between anisometropia and aniseikonia (ANK) is not well understood. Ametropic cataract patients provide a unique opportunity to study this relationship after undergoing emmetropizing lens extraction. Because light scatter may affect ANK measurement in cataract patients, its effect should also be evaluated. The Basic Aniseikonia Test (BAT) was evaluated using afocal size lenses to produce specific changes in retinal height. Several light scattering devices were then evaluated to determine which produced effects most similar to cataract. Contrast sensitivity and visual acuity (VA) losses were measured with each device and compared to those reported in cataract. After determining the most appropriate light scattering device, twenty healthy patients with normal visual function were recruited to perform the BAT using the filters to simulate cataract. Cataract patients were recruited from Vision America and the University of Alabama at Birmingham School of Optometry. Patients between 20 and 75 years of age with at least 20/80 VA in each eye, ≥ 2D ametropia, and normal binocular function were recruited. Stereopsis and ANK were tested and each patient completed a symptom questionnaire. ANK measurements using afocal size lenses indicated that the BAT underestimates ANK, although the effect was minimal for vertical targets and darkened surroundings, as previously reported. Based on VA and contrast sensitivity loss, Vistech scattering filters produced changes most similar to cataract. Results of the BAT using Vistech filters demonstrated that a moderate cataract but not a mild cataract may affect the ANK measurement. ANK measurements on cataract patients indicated that those with ≥ 2 D ametropia in each eye may suffer from induced ANK after the first cataract extraction. With upcoming healthcare reform, unilateral cataract extraction may be covered, but not necessarily bilateral, depending on patient VA in each eye. However, a questionnaire about symptoms at each visit in the current study showed that visual comfort did not improve after unilateral, but did improve after bilateral, cataract extraction. This indicates that quality of life should be better in bilateral cataract patients only if both cataracts are removed. This is supported by the findings of other studies. Keywords: Aniseikonia, Anisometropia, Cataract, Ametropia

General analysis of factors influencing cataract surgery practice in Shanghai residents.

PubMed

Xu, Yi; He, Jiangnan; Lin, Senlin; Zhang, Bo; Zhu, Jianfeng; Resnikoff, Serge; Lu, Lina; Zou, Haidong

2018-04-18

It was reported that lack of knowledge, less confidence of medical services, commute difficulties, and poor economic conditions would be the main barriers for cataract surgery practice. The influencing factors could have changed in cities with high developing speed. Shanghai is one of the biggest cities in China and the world. The purpose of the study was to explore the factors influencing cataract surgery practice in Shanghai. This was a population-based, cross-sectional study. A total of 2342 cataract patients older than 50 years old with cataract-induced visual impairment or who had undergone cataract surgery were recruited from rural and urban areas of Shanghai. Participants accepted a face-to-face structured questionnaire. Data were collected on patient demographics, education, work, income, health insurance, awareness about cataracts disease, treatment and related medical resources and deration policy, transportation and degree of satisfaction with hospitals. There were 417 patients who had received cataract surgery, 404 of them supplied complete information in the questionnaire. More female subjects (64.6%) than male subjects (35.4%) accepted cataract surgery among the 404 patients. Of the patients with cataract history, 36.4% of surgery patients were equal or older than 80. More people with urban medical insurance received surgery (p = 0.036). Patients who received surgery were more satisfied with local medical service (p = 0.032). In urban area, Lower income and difficulties with commutes were related to a higher rate of surgery. Cataract patients with the following features were more inclined to receive surgery: female, old age, better awareness. In urban areas low income and difficult commutes did not represent barriers for cataract surgery, probably because of appropriate cataract surgery promotion policies recent years in Shanghai. In rural areas, better healthcare reimbursement policies would likely lead to a higher uptake of cataract surgery. Further cohort studies with more controls could supply stronger evidence for our viewpoint.

Solar ultraviolet radiation in Africa: a systematic review and critical evaluation of the health risks and use of photoprotection.

PubMed

Lucas, Robyn M; Norval, Mary; Wright, Caradee Y

2016-01-01

Most information on the harmful health effects of solar ultraviolet radiation (UVR) has been obtained in populations in which the majority has fair skin. Here a systematic review of evidence on diseases related to solar UVR in Africa was undertaken, and the appropriateness of effective photoprotection for these people considered. There are few population-based studies on UV-induced skin cancers (melanoma, squamous and basal cell carcinomas) in Africa, although limited reports indicated that they occur, even in people with deeply pigmented skin. The incidence of melanoma is particularly high in the white population living in the Western Cape of South Africa and has increased significantly in recent years. Cataract is extremely common in people of all skin colours and is a frequent cause of blindness, particularly in the elderly. For both skin cancer and cataract, the proportion of the disease risk that is attributable to exposure to solar UVR in African populations, and therefore the health burden caused by UV irradiation is unclear. There was little published information on the use of sun protection in Africa. The potential disease burden attributable to solar UVR exposure of Africans is high, although accurate data to quantify this are sparse. Information is required on the incidence, prevalence and mortality for the range of UV-related diseases in different populations living throughout Africa. Photoprotection is clearly required, at least for those subpopulations at particularly high risk, but may be limited by cost and cultural acceptability.

Prevention effect in selenite-induced cataract in vivo and antioxidative effects in vitro of Crataegus pinnatifida leaves.

PubMed

Wang, Tao; Zhang, Peng; Zhao, Chunfeng; Zhang, Yi; Liu, Hong; Hu, Limin; Gao, Xiumei; Zhang, Deqin

2011-07-01

Cataract is the leading cause of blindness worldwide. It is a multifactorial disease primarily associated with oxidative stress produced by free radicals. The present study was undertaken to evaluate the anticataract potential of Crataegus pinnatifida (hawthorn tree) leaves extract in selenite-induced cataract in vivo and antioxidant effects in vitro. In vitro antioxidant assay of C. pinnatifida leaves extract on NO production inhibition, aldose reductase inhibition, and O(2)(-) radical scavenging activities gave the IC(50) of 98.3, 89.7, and 5.98 μg/mL, respectively. To characterize some major compounds in C. pinnatifida leaves extract, nine flavonoids were identified via LC-MS/MS qualitative analysis. Based on in vitro screening results, C. pinnatifida leaves extract eye drops in 0.1% hydroxypropyl methyl cellulose solution were prepared to evaluate the anticataract potential in vivo. Administration of C. pinnatifida leaves extract eye drops alternately three times a day in rat pups with selenite-induced oxidative stress significantly increased serum SOD and CAT activities, and tended to reduce MDA level compared with control group. The antioxidant enzyme SOD, CAT, and GSH activities in lens showed a significant increase. These results may be applied in the future for the prevention and treatment of cataracts.

A method to reduce patient's eye lens dose in neuro-interventional radiology procedures

NASA Astrophysics Data System (ADS)

Safari, M. J.; Wong, J. H. D.; Kadir, K. A. A.; Sani, F. M.; Ng, K. H.

2016-08-01

Complex and prolonged neuro-interventional radiology procedures using the biplane angiography system increase the patient's risk of radiation-induced cataract. Physical collimation is the most effective way of reducing the radiation dose to the patient's eye lens, but in instances where collimation is not possible, an attenuator may be useful in protecting the eyes. In this study, an eye lens protector was designed and fabricated to reduce the radiation dose to the patients' eye lens during neuro-interventional procedures. The eye protector was characterised before being tested on its effectiveness in a simulated aneurysm procedure on an anthropomorphic phantom. Effects on the automatic dose rate control (ADRC) and image quality are also evaluated. The eye protector reduced the radiation dose by up to 62.1% at the eye lens. The eye protector is faintly visible in the fluoroscopy images and increased the tube current by a maximum of 3.7%. It is completely invisible in the acquisition mode and does not interfere with the clinical procedure. The eye protector placed within the radiation field of view was able to reduce the radiation dose to the eye lens by direct radiation beam of the lateral x-ray tube with minimal effect on the ADRC system.

Space Radiation

NASA Technical Reports Server (NTRS)

Wu, Honglu

2006-01-01

Astronauts receive the highest occupational radiation exposure. Effective protections are needed to ensure the safety of astronauts on long duration space missions. Increased cancer morbidity or mortality risk in astronauts may be caused by occupational radiation exposure. Acute and late radiation damage to the central nervous system (CNS) may lead to changes in motor function and behavior, or neurological disorders. Radiation exposure may result in degenerative tissue diseases (non-cancer or non-CNS) such as cardiac, circulatory, or digestive diseases, as well as cataracts. Acute radiation syndromes may occur due to occupational radiation exposure.

Risks of radiation cataracts from interplanetary space missions.

PubMed

Lett, J T; Lee, A C; Cox, A B

1994-11-01

Recognition of the human risks from radiation exposure during manned missions in deep space has been fostered by international co-operation; interagency collaboration is facilitating their evaluation. Further co-operation can lead, perhaps by the end of this decade, to an evaluation of one of the three major risks, namely radiation cataractogenesis, sufficient for use in the planning of the manned mission to Mars.

Synthesis and biological evaluation of novel gigantol derivatives as potential agents in prevention of diabetic cataract

USDA-ARS?s Scientific Manuscript database

As a continuation of our efforts directed towards the development of natural anti-diabetic cataract agents, gigantol was isolated from Herba dendrobii and was found to inhibit both aldose reductase (AR) and inducible nitric oxide synthase (iNOS) activity, which play a significant role in the develop...

Glutathione and catalase suppress TGFβ-induced cataract-related changes in cultured rat lenses and lens epithelial explants

PubMed Central

Chamberlain, Coral G.; Cerra, Anna

2009-01-01

Purpose The damaging effects of oxidative stress and transforming growth factor-β (TGFβ)-induced transdifferentiation of lens epithelial cells have both been implicated independently in the etiology of cataract. The aim of this study was to investigate whether the presence of antioxidant systems in the lens influences the ability of lens epithelial cells to respond to TGFβ. Methods Whole lenses from young rats were cultured with or without TGFβ in the presence or absence of reduced glutathione (GSH). Lens epithelial explants from weanling rats were used to investigate the effects of GSH and catalase on TGFβ-induced cataract-related changes. Lenses were monitored for opacification for three to four days, photographed, and then processed for routine histology. Explants were assessed by phase contrast microscopy, enzyme-linked immunosorbent assay (ELISA) of α-smooth muscle actin (αSMA), and/or immunolocalization of αSMA and Pax6, markers for transdifferentiation and normal lens epithelial phenotype, respectively. Results In cultured lenses, GSH strongly suppressed TGFβ-induced opacification and subcapsular plaque formation. In explants, both GSH and catalase suppressed changes typically associated with TGFβ-induced transdifferentiation including wrinkling of the lens capsule, cell-surface blebbing, apoptotic cell loss, induction of αSMA, and loss of Pax6 expression. Conclusions This study suggests that antioxidant systems present in the normal lens, which protect the epithelium against the damaging effects of reactive oxygen species, may also serve to protect it against the potentially cataractogenic effects of TGFβ. Taken together with other recent studies, it also raises the possibility that TGFβ may induce cataract-related changes in lens epithelial cells via release of hydrogen peroxide. PMID:19421408

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hata, Masaharu, E-mail: mhata@syd.odn.ne.jp; Omura, Motoko; Koike, Izumi

Purpose: Among extranodal lymphomas, orbital mucosa-associated lymphoid tissue (MALT) lymphoma is a relatively rare presentation. We performed a review to ascertain treatment efficacy and toxicity of radiation therapy for orbital MALT lymphoma. We also evaluated changes in visual acuity after irradiation. Methods and Materials: Thirty patients with orbital MALT lymphoma underwent radiation therapy with curative intent. Clinical stages at diagnosis were stage I{sub E}A in 29 patients and stage II{sub E}A in 1 patient. Total doses of 28.8 to 45.8 Gy (median, 30 Gy) in 15 to 26 fractions (median, 16 fractions) were delivered to the tumors. Results: All irradiatedmore » tumors were controlled during the follow-up period of 2 to 157 months (median, 35 months) after treatment. Two patients had relapses that arose in the cervical lymph node and the ipsilateral palpebral conjunctiva outside the radiation field at 15 and 67 months after treatment, respectively. The 5-year local progression-free and relapse-free rates were 100% and 96%, respectively. All 30 patients are presently alive; the overall and relapse-free survival rates at 5 years were 100% and 96%, respectively. Although 5 patients developed cataracts of grade 2 at 8 to 45 months after irradiation, they underwent intraocular lens implantation, and their eyesight recovered. Additionally, there was no marked deterioration in the visual acuity of patients due to irradiation, with the exception of cataracts. No therapy-related toxicity of grade 3 or greater was observed. Conclusions: Radiation therapy was effective and safe for patients with orbital MALT lymphoma. Although some patients developed cataracts after irradiation, visual acuity was well preserved.« less

Eye lens dosimetry and the study on radiation cataract in interventional cardiologists.

PubMed

Matsubara, Kosuke; Lertsuwunseri, Vorarit; Srimahachota, Suphot; Krisanachinda, Anchali; Tulvatana, Wasee; Khambhiphant, Bharkbhum; Sudchai, Waraporn; Rehani, Madan

2017-12-01

To determine the eye lens dose of the Interventional Cardiology (IC) personnel using optically stimulated luminescent dosimeter (OSLD) and the prevalence and risk of radiation - associated lens opacities in Thailand. 48 IC staff, with age- and sex- matches 37 unexposed controls obtained eye examines. Posterior lens change was graded using a modified Merriam-Focht technique by two independent ophthalmologists. Occupational exposure (mSv) was measured in 42 IC staff, using 2 OSLD badges place at inside lead apron and at collar. Annual eye lens doses (mSv) were also measured using 4 nanoDots OSL placed outside and inside lead glass eyewear. The prevalence of radiation-associated posterior lens opacities was 28.6% (2/7) for IC, 19.5% (8/41) for nurses, and 2.7% (1/37) for controls. The average and range of annual whole body effective dose, Hp(10), equivalent dose at skin of the neck, Hp(0.07) and equivalent dose at eye lens, Hp(3) were 0.80 (0.05-6.79), 5.88 (0.14-35.28), and 5.73 (0.14-33.20) mSv respectively. The annual average and range of eye lens dose using nano Dots OSL showed the outside lead glass eyewear on left and right sides as 8.06 (0.17-32.45), 3.55(0.06-8.04) mSv and inside left and right sides as 3.91(0.05-14.26) and 2.44(0.06-6.24) mSv respectively. Eye lens doses measured by OSLD badges and nano Dot dosimeter as Hp(10), Hp(0.07) and Hp(3). The eyes of the IC personnel were examined annually by two ophthalmologists for the prevalence of cataract induced by radiation. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Allopurinol therapy and cataractogenesis in humans

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lerman, S.; Megaw, J.M.; Gardner, K.

1982-08-01

Long-term ingestion of allopurinol, an antihyperuricemic agent used to treat gout, may be related to the development of lens opacities in relatively young patients (second to fifth decades of life). Cataracts obtained from three patients taking allopurinol were subjected to high-resolution phosphorescence spectroscopy. The characteristic allopurinol triplet was demonstrated in all three cataracts. Identical spectra were obtained for normal human lenses incubated in media containing 10(-3)M allopurinol and exposed to 1.2 mW/cm2 ultraviolet radiation for 16 hours; control lenses (irradiated without allopurinol) showed no allopurinol triplets. Similar data were obtained for lenses from rats given one dose of allopurinol andmore » exposed to ultraviolet radiation overnight. These data provide evidence that allopurinol can be photobound in rat and human lenses and suggest its cataractogenic potential.« less

Free radicals, antioxidants and eye diseases: evidence from epidemiological studies on cataract and age-related macular degeneration.

PubMed

Fletcher, A E

2010-01-01

Cataract and age-related macular degeneration (AMD) are the major causes of vision impairment and blindness worldwide. Both conditions are strongly age related with earlier signs (usually asymptomatic) occurring in middle age and becoming severer and more prevalent with increasing age. The aetiology of these conditions is thought to fit with the 'free radical theory' of ageing which postulates that ageing and age-related diseases result from the accumulation of cellular damage from reactive oxygen species (ROS). Mitochondrial energy production is a major source of endogenous ROS. External sources of ROS include environmental sources especially solar radiation, biomass fuels and tobacco smoking. There is strong evidence from epidemiological studies that smoking is a risk factor for both cataract and AMD. There is moderate evidence for an association with sunlight and cataract but weak evidence for sunlight and AMD. The few studies that have investigated this suggest an adverse effect of biomass fuels on cataract risk. The antioxidant defence system of the lens and retina include antioxidant vitamins C and E and the carotenoids lutein and zinc, and there is mixed evidence on their associations with cataract and AMD from epidemiological studies. Most epidemiological studies have been conducted in well-nourished western populations but evidence is now emerging from other populations with different dietary patterns and antioxidant levels. Copyright 2010 S. Karger AG, Basel.

Sprouty Is a Negative Regulator of Transforming Growth Factor β–Induced Epithelial-to-Mesenchymal Transition and Cataract

PubMed Central

Shin, Eun Hye H; Basson, M Albert; Robinson, Michael L; McAvoy, John W; Lovicu, Frank J

2012-01-01

Fibrosis affects an extensive range of organs and is increasingly acknowledged as a major component of many chronic disorders. It is now well accepted that the elevated expression of certain inflammatory cell–derived cytokines, especially transforming growth factor β (TGFβ), is involved in the epithelial-to-mesenchymal transition (EMT) leading to the pathogenesis of a diverse range of fibrotic diseases. In lens, aberrant TGFβ signaling has been shown to induce EMT leading to cataract formation. Sproutys (Sprys) are negative feedback regulators of receptor tyrosine kinase (RTK)-signaling pathways in many vertebrate systems, and in this study we showed that they are important in the murine lens for promoting the lens epithelial cell phenotype. Conditional deletion of Spry1 and Spry2 specifically from the lens leads to an aberrant increase in RTK-mediated extracellular signal-regulated kinase 1/2 phosphorylation and, surprisingly, elevated TGFβ-related signaling in lens epithelial cells, leading to an EMT and subsequent cataract formation. Conversely, increased Spry overexpression in lens cells can suppress not only TGFβ-induced signaling, but also the accompanying EMT and cataract formation. On the basis of these findings, we propose that a better understanding of the relationship between Spry and TGFβ signaling will not only elucidate the etiology of lens pathology, but will also lead to the development of treatments for other fibrotic-related diseases associated with TGFβ-induced EMT. PMID:22517312

Towards standardization of UV eye protection: what can be learned from photodermatology?

PubMed

Krutmann, Jean; Béhar-Cohen, Francine; Baillet, Gilles; de Ayguavives, Tito; Ortega Garcia, Paula; Peña-García, Pablo; Remé, Charlotte; Wolffsohn, James

2014-01-01

While knowledge about standardization of skin protection against ultraviolet radiation (UVR) has progressed over the past few decades, there is no uniform and generally accepted standardized measurement for UV eye protection. The literature provides solid evidence that UV can induce considerable damage to structures of the eye. As well as damaging the eyelids and periorbital skin, chronic UV exposure may also affect the conjunctiva and lens. Clinically, this damage can manifest as skin cancer and premature skin ageing as well as the development of pterygia and premature cortical cataracts. Modern eye protection, used daily, offers the opportunity to prevent these adverse sequelae of lifelong UV exposure. A standardized, reliable and comprehensive label for consumers and professionals is currently lacking. In this review we (i) summarize the existing literature about UV radiation-induced damage to the eye and surrounding skin; (ii) review the recent technological advances in UV protection by means of lenses; (iii) review the definition of the Eye-Sun Protection Factor (E-SPF®), which describes the intrinsic UV protection properties of lenses and lens coating materials based on their capacity to absorb or reflect UV radiation; and (iv) propose a strategy for establishing the biological relevance of the E-SPF. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Efficacy of the RADPAD Protection Drape in Reducing Operators' Radiation Exposure in the Catheterization Laboratory: A Sham-Controlled Randomized Trial.

PubMed

Vlastra, Wieneke; Delewi, Ronak; Sjauw, Krischan D; Beijk, Marcel A; Claessen, Bimmer E; Streekstra, Geert J; Bekker, Robbert J; van Hattum, Juliette C; Wykrzykowska, Joanna J; Vis, Marije M; Koch, Karel T; de Winter, Robbert J; Piek, Jan J; Henriques, José P S

2017-11-01

Interventional cardiologists are increasingly exposed to radiation-induced diseases like cataract and the stochastic risk of left-sided brain tumors. The RADPAD is a sterile, disposable, lead-free shield placed on the patient with the aim to minimize operator-received scatter radiation. The objective of the trial was to examine the RADPAD's efficacy in a real-world situation. In the current, double-blind, sham-controlled, all-comer trial, patients undergoing diagnostic catheterization or percutaneous coronary interventions were randomized in a 1:1:1 ratio to a radiation absorbing shield (RADPAD), standard treatment (NOPAD), or a sham shield (SHAMPAD). The sham shield allowed testing for shield-induced radiation behavior. The primary outcome was the difference in relative exposure of the primary operator between the RADPAD and NOPAD arms and was defined as the ratio between operator's exposure (E in µSv) and patient exposure (dose area product in mGy·cm 2 ), measured per procedure. A total of 766 consecutive coronary procedures were randomized to the use of RADPAD (N=255), NOPAD (N=255), or SHAMPAD (N=256). The use of RADPAD was associated with a 20% reduction in relative operator exposure compared with that of NOPAD ( P =0.01) and a 44% relative exposure reduction compared with the use of a SHAMPAD ( P <0.001). Use of the SHAMPAD was associated with a 43% higher relative radiation exposure than procedures with NOPAD ( P =0.009). In clinical daily practice, the standard use of the RADPAD radiation shield reduced operator radiation exposure compared with procedures with NOPAD or SHAMPAD. This study supports the routine use of RADPAD in the catheterization laboratory. URL: https://www.clinicaltrials.gov. Unique identifier: NCT03139968. © 2017 American Heart Association, Inc.

Detection of DNA damage by space radiation in human fibroblast cells flown on the International Space Station

NASA Astrophysics Data System (ADS)

Wu, Honglu; Feiveson, Alan; Karouia, Fathi; Stodieck, Louis; Zhang, Ye; Lu, Tao; Wong, Michael

2016-07-01

Although charged particles in space have been detected with radiation detectors on board the spacecraft since the early discovery of the Van Allen Belts, reports on the effects of direct exposure to space radiation in biological systems have been limited. Measurement of biological effects of space radiation has been difficult due to the low dose and low dose rate nature of the radiation environment, and the difficulty in separating the radiation effects from microgravity and other space environmental factors. In astronauts, only a few changes, such as increased chromosome aberrations in lymphocytes and early onset of cataracts, attributed primarily to the exposure to space radiation. In a recent experiment, human fibroblast cells were flown on the International Space Station (ISS). Cells were kept at 370C in space and fixed on Days 3 and 14 after reaching orbit. After returning to the ground, the fixed cells were analyzed for phosphorylation of a histone protein H2AX by immunofluorescent staining of cells, which is a widely used biomarker for DNA double strand breaks. The 3-dimensional γg-H2AX foci were captured with a laser confocal microscope. Quantitative analysis revealed a small fraction of foci that were larger and displayed a track pattern in the flight samples in comparison to the ground controls. To confirm that the foci data from the flight study was actually induced from space radiation exposure, human fibroblast cells were exposed to low- and high-LET protons and high-LET Fe ions on the ground. High-LET protons and Fe ions were found to induce foci of the pattern that were observed in the flown cells.

The influence of dose, dose-rate and particle fragmentation on cataract induction by energetic iron ions

NASA Technical Reports Server (NTRS)

Medvedovsky, C.; Worgul, B. V.; Huang, Y.; Brenner, D. J.; Tao, F.; Miller, J.; Zeitlin, C.; Ainsworth, E. J.

1994-01-01

Because activities in space necessarily involve chronic exposure to a heterogeneous charged particle radiation field it is important to assess the influence of dose-rate and the possible modulating role of heavy particle fragmentation on biological systems. Using the well-studied cataract model, mice were exposed to plateau 600 MeV/amu Fe-56 ions either as acute or fractionated exposures at total doses of 5-504 cGy. Additional groups of mice received 20, 360 and 504 cGy behind 50 mm of polyethylene, which simulates body shielding. The reference radiation consisted of Co-60 gamma radiation. The animals were examined by slit lamp biomicroscopy over their three year life spans. In accordance with our previous observations with heavy particles, the cataractogenic potential of the 600 MeV/amu Fe-56 ions was greater than for low-Linear Energy Transfer (LET) radiation and increased with decreasing dose relative to gamma rays. Fractionation of a given dose of Fe-56 ions did not reduce the cataractogenicity of the radiation compared to the acute regimen. Fragmentation of the beam in the polyethylene did not alter the cataractotoxicity of the ions, either when administered singly or in fractions.

The influence of dose, dose-rate and particle fragmentation on cataract induction by energetic iron ions

NASA Astrophysics Data System (ADS)

Medvedovsky, C.; Worgul, B. V.; Huang, Y.; Brenner, D. J.; Tao, F.; Miller, J.; Zeitlin, C.; Ainsworth, E. J.

1994-10-01

Because activities in space necessarily involve chronic exposure to a heterogeneous charged particle radiation field it is important to assess the influence of dose-rate and the possible modulating role of heavy particle fragmentation on biological systems. Using the well-studied cataract model, mice were exposed to plateau 600 MeV/amu 56Fe ions either as acute or fractionated exposures at total doses of 5 - 504 cGy. Additional groups of mice received 20, 360 and 504 cGy behind 50 mm of polyethylene, which simulates body shielding. The reference radiation consisted of 60Co γ radiation. The animals were examined by slit lamp biomicroscopy over their three year life spans. In accordance with our previous observations with heavy particles, the cataractogenic potential of the 600 MeV/amu 56Fe ions was greater than for low-LET radiation and increased with decreasing dose relative to γ-rays. Fractionation of a given dose of 56Fe ions did not reduce the cataractogenicity of the radiation compared to the acute regimen. Fragmentation of the beam in the polyethylene did not alter the cataractotoxicity of the ions, either when administered singly or in fractions.

Outcome of cataract surgery following simple limbal epithelial transplantation for lime injury-induced limbal stem cell deficiency

PubMed Central

Nair, Dhanyasree

2015-01-01

A 19-year-old woman presented to us after being diagnosed elsewhere with right eye total limbal stem cell deficiency resulting from a lime burn. She was advised to undergo limbal stem cell transplantation, but failed to immediately do so. Two years later, she underwent cultivated limbal epithelial transplantation (CLET). As she had severe loss of vision with persisting conjunctival nodule and symblepharon 2 years following surgery, an impression of failed CLET was formed. Subsequently, simple limbal epithelial transplantation (SLET) was performed. Nine months later, she developed a cataract in her right eye; the cataract was extracted and posterior chamber intraocular lens implanted. The unaided visual acuity improved from light perception at presentation to 20/60 at 1-week postoperatively. At 5 months follow-up, the patient continued to maintain 20/60 visual acuity in her right eye. This case describes the outcome of cataract surgery following SLET, emphasising the need to perform cataract surgery in complicated cataracts for a better visual prognosis. PMID:26698204

Lack of Radiation Maculopathy After Palladium-103 Plaque Radiotherapy for Iris Melanoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yousef, Yacoub A.; Finger, Paul T., E-mail: pfinger@eyecancer.com

2012-07-15

Purpose: To report on the risk of radiation maculopathy for iris and iridociliary melanomas treated by {sup 103}Pd plaque radiotherapy. Methods and Materials: This is a retrospective clinical case series of 30 eyes in 30 patients with melanomas limited to the iris or invading the ciliary body. The main outcome measures included demographic information, laterality, tumor size, location, visual acuity, radiation dose, local control, retinal evaluation, and duration of follow-up. Results: Thirty patients were followed for a median 36 months (range, 12-90 months). Sixteen of 30 tumors (53%) were pure iris melanomas, and 14 (47%) were primary iris melanomas extendingmore » into the ciliary body. Radiation dosimetry showed that the median tumor apex dose was 85 Gy (range, 75-100 Gy), lens dose 43.5 Gy (range, 17.8-60 Gy), fovea dose 1.8 Gy (range, 1.3-5 Gy), and central optic disc dose 1.7 Gy (range, 1.3-4.7 Gy). Cataracts developed in 20 of the 28 phakic eyes (71.4%). No patient in this series developed radiation maculopathy or radiation optic neuropathy. Last best-corrected visual acuity was {>=}20/25 in 28 patients (93%) at a median 36 months' follow-up. Conclusion: Though visual acuities were transiently affected by radiation cataract, no radiation maculopathy or optic neuropathy has been noted after {sup 103}Pd treatment of iris and iridociliary melanomas.« less

Lightless cataract surgery using a near-infrared operating microscope.

PubMed

Kim, Bong-Hyun

2006-10-01

To describe the near-infrared (NIR) operating microscopy (NIOM) system using the NIR wavelength as the illumination source and to evaluate the feasibility of this system for lightless cataract surgery. HenAm Kim Eye Center, Haenam-Gun, South Korea. In this noncomparative interventional case series, cataract surgery was performed in 4 patients with bilateral cataract using the NIOM system in 1 eye and conventional microscopy in the fellow eye. The primary components of the system include an optical filter, a stereoscopic camera, head-mounted displays, and a recording system. This system uses invisible NIR (wavelength 850 to 1300 nm) illumination to facilitate cataract surgery without light. The differences between the NIOM system and conventional microscopy during cataract surgery were evaluated. The NIOM system provided excellent 3-dimensional viewing in real time. The image resolution was sufficient while performing all steps of cataract surgery. Immediately postoperatively and at 10 and 30 minutes and 1 hour, the visual acuity was better in the 4 eyes in which the NIOM system was used than in the 4 eyes in which conventional microscopy was used. However, using the NIOM system required good surgical skill. Lightless cataract surgery using the NIOM system seems useful for obtaining good visual acuity immediately postoperatively. The system may also reduce the incidence of light-induced retinal toxicity and the need for mydriatic administration and be a good educational tool.

Space radiation risk limits and Earth-Moon-Mars environmental models

NASA Astrophysics Data System (ADS)

Cucinotta, Francis A.; Hu, Shaowen; Schwadron, Nathan A.; Kozarev, K.; Townsend, Lawrence W.; Kim, Myung-Hee Y.

2010-12-01

We review NASA's short-term and career radiation limits for astronauts and methods for their application to future exploration missions outside of low Earth orbit. Career limits are intended to restrict late occurring health effects and include a 3% risk of exposure-induced death from cancer and new limits for central nervous system and heart disease risks. Short-term dose limits are used to prevent in-flight radiation sickness or death through restriction of the doses to the blood forming organs and to prevent clinically significant cataracts or skin damage through lens and skin dose limits, respectively. Large uncertainties exist in estimating the health risks of space radiation, chiefly the understanding of the radiobiology of heavy ions and dose rate and dose protraction effects, and the limitations in human epidemiology data. To protect against these uncertainties NASA estimates the 95% confidence in the cancer risk projection intervals as part of astronaut flight readiness assessments and mission design. Accurate organ dose and particle spectra models are needed to ensure astronauts stay below radiation limits and to support the goal of narrowing the uncertainties in risk projections. Methodologies for evaluation of space environments, radiation quality, and organ doses to evaluate limits are discussed, and current projections for lunar and Mars missions are described.

Status of NCRP Scientific Committee 1-23 Commentary on Guidance on Radiation Dose Limits for the Lens of the Eye.

PubMed

Dauer, Lawrence T; Ainsbury, Elizabeth A; Dynlacht, Joseph; Hoel, David; Klein, Barbara E K; Mayer, Don; Prescott, Christina R; Thornton, Raymond H; Vano, Eliseo; Woloschak, Gayle E; Flannery, Cynthia M; Goldstein, Lee E; Hamada, Nobuyuki; Tran, Phung K; Grissom, Michael P; Blakely, Eleanor A

2016-02-01

Previous National Council on Radiation Protection and Measurements (NCRP) publications have addressed the issues of risk and dose limitation in radiation protection and included guidance on specific organs and the lens of the eye. NCRP decided to prepare an updated commentary intended to enhance the previous recommendations provided in earlier reports. The NCRP Scientific Committee 1-23 (SC 1-23) is charged with preparing a commentary that will evaluate recent studies on the radiation dose response for the development of cataracts and also consider the type and severity of the cataracts as well as the dose rate; provide guidance on whether existing dose limits to the lens of the eye should be changed in the United States; and suggest research needs regarding radiation effects on and dose limits to the lens of the eye. A status of the ongoing work of SC 1-23 was presented at the Annual Meeting, "Changing Regulations and Radiation Guidance: What Does the Future Hold?" The following represents a synopsis of a few main points in the current draft commentary. It is likely that several changes will be forthcoming as SC 1-23 responds to subject matter expert review and develops a final document, expected by mid 2016.

Mice heterozygous for the ATM gene are more sensitive to heavy ions exposure than are wildtypes

NASA Astrophysics Data System (ADS)

Worgul, B.; Smilenov, L.; Brenner, D.; Vazquez, M.; Hall, E.

Previous studies have shown that the eyes of atm heterozygous mice exposed to Low LET radiation (X-rays) are more susceptible to the development of cataracts than are those of wildtype mice. The findings, as well as others, run counter to the assumption underpinning current radiation safety guidelines, that individuals are all equally sensitive to the biological effects of radiation. A question, highly relevant to human space activities is whether or not, in similar fashion there may exist a genetic predisposition to High LET radiation damage. Again the lens and, its primary radiopathy, cataract, were used to assay for the effects of ATM deficiency in a late-responding tissue. Together with those of wildtypes, the eyes of AT heterozygous knockout mice were exposed to 325 mGy of 1 GEV/amu 56Fe ions at the AGS facility of Brookhaven National Laboratory. The fluence was equivalent to 1 ion per nuclear area. As was the case in the earlier X-ray studies all irradiations were done on the 28th day after birth. Controls consisted of wildtype irradiated as well as unirradiated wildtype and heterozygotes. Ten mice from each group were examined weekly by conventional slitlamp biomicroscopy for a total of 35 weeks. The time required for prevalence to reach 50% (T50) as an endpoint for each stage indicated that not only cataract onset but also progression were accelerated in the mice haplo-deficient for the atm gene. For example the T50 for definitive cataract onset (stage 1) in the atm heterozygotes was 10 weeks whereas 17 weeks were required for the wildtypes. Similarly at the conclusion of the experiment (35 weeks), 40% of the lenses of allele-deficient mice had progressed to stage 3 (near fully opaque and obviously visually debilitating), while only one lens (5%) from the wildtype irradiated eyes achieved that stage. The data show that heterozygosity for the atm gene predisposes the eye to the cataractogenic influence of heavy ions and suggest that AT heterozygotes in the human population may also be radiosensitive. This may have to be considered in the selection of individuals who will be exposed to both HZE particles and Low-LET radiation as they may be predisposed to increased late normal tissue damage. Supported by NASA Grant NAG 9-1148 and Research to Prevent Blindness, Inc.

Contribution of Cholesterol and Oxysterols in the Physiopathology of Cataract: Implication for the Development of Pharmacological Treatments

PubMed Central

Vejux, Anne; Samadi, Mohammad; Lizard, Gérard

2011-01-01

The development of cataract is associated with some lipid changes in human lens fibers, especially with increased accumulation and redistribution of cholesterol inside these cells. Some direct and indirect lines of evidence, also suggest an involvement of cholesterol oxide derivatives (also named oxysterols) in the development of cataract. Oxysterol formation can result either from nonenzymatic or enzymatic processes, and some oxysterols can induce a wide range of cytotoxic effects (overproduction of reactive oxygen species (ROS); phospholipidosis) which might contribute to the initiation and progression of cataract. Thus, the conception of molecules capable of regulating cholesterol homeostasia and oxysterol levels in human lens fibers can have some interests and constitute an alternative to surgery at least at early stages of the disease. PMID:21577274

Antioxidant potential of fungal metabolite nigerloxin during eye lens abnormalities in galactose-fed rats.

PubMed

Suresha, Bharathinagar S; Srinivasan, Krishnapura

2013-10-01

The role of osmotic and oxidative stress has been strongly implicated in the pathogenesis of cataract. Nigerloxin, a fungal metabolite, has been shown to possess aldose reductase inhibition and improved antioxidant defense system in lens of diabetic rats. In the present study, the beneficial influence of nigerloxin was investigated in galactose-induced cataract in experimental animals. Cataract was induced in Wistar rats by feeding 30% galactose in diet. Groups of galactose-fed rats were orally administered with nigerloxin (25 and 100 mg/kg body weight/day) for 24 days. Lens aldose reductase activity was increased significantly in galactose-fed animals. Lens lipid peroxides and advanced glycation end products were also significantly increased. Antioxidant molecule - reduced glutathione, total thiols and activities of antioxidant enzymes superoxide dismutase and glutathione peroxidase were decreased in the lens of galactose-fed animals. Oral administration of nigerloxin once a day for 24 days at a dose of 100 mg/kg body weight, significantly decreased lens lipid peroxides and advanced glycation end products in galactose-fed rats. Lens aldose reductase activity was reduced and lens antioxidant molecules and antioxidant enzyme activities were elevated significantly by nigerloxin administration. The results suggest that alteration in polyol pathway and antioxidant defense system were countered by nigerloxin in the lens of galactose-fed animals, suggesting the potential of nigerloxin in ameliorating the development of galactose-induced cataract in experimental animals.

Polyphenols of Cassia tora leaves prevents lenticular apoptosis and modulates cataract pathology in Sprague-Dawley rat pups.

PubMed

Sreelakshmi, V; Abraham, Annie

2016-07-01

Cataract is a leading cause of visual impairment worldwide with multifactorial etiology and is a significant global health problem with increasing prevalence with age. Currently, no pharmacological measures are discovered to prevent and treat cataract and a significant number of epidemiological studies have suggested the potential role of antioxidants in the prevention of cataract by scavenging free radicals and preventing lens protein derangement and lenticular cell damage. The main goal of the present study is to evaluate Cassia tora leaves; an edible leafy vegetable employed in Ayurvedic and Chinese system of medicine for eye rejuvenation in preventing selenite-induced cataract in rat pups and to identify the active components that produce the effect. ECT pre-treatment effectively restored both enzymatic and metabolic antioxidant levels, membrane integrity and reduced metal accumulation and thus down-regulate epithelial cell death. Gene expression studies also confirmed these findings. ESI-MS analysis of ECT revealed the presence of chrysophanol, emodin, kaemferol, quercetin, stigmasterol and isoquercetin. The study suggests the possible role of C. tora in alleviating cataract pathology and presence of many anthraquinones and flavonoids. As it is an edible plant, the incorporation of these leaves in daily vegetables might prevent or delay the onset and maturation of cataract. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

A Review of Non-Cancer Effects, Especially Circulatory and Ocular Diseases1

PubMed Central

Little, Mark P.

2014-01-01

There is a well-established association between high doses (> 5 Gy) of ionizing radiation exposure and damage to the heart and coronary arteries, although only recently have studies with high quality individual dosimetry been conducted that would enable quantification of this risk adjusting for concomitant chemotherapy. The association between lower dose exposures and late occurring circulatory disease has only recently begun to emerge in the Japanese atomic bomb survivors and in various occupationally-exposed cohorts, and is still controversial. Excess relative risks per unit dose in moderate and low dose epidemiological studies are somewhat variable, possibly a result of confounding and effect modification by well known (but unobserved) risk factors. Radiation doses of 1 Gy or more are associated with increased risk of posterior subcapsular cataract. Accumulating evidence from the Japanese atomic bomb survivors, Chernobyl liquidators, US astronauts and various other exposed groups suggest that cortical cataracts may also be associated with ionizing radiation, although there is little evidence that nuclear cataracts are radiogenic. The dose response appears to be linear, although modest thresholds (of no more than about 0.6 Gy) cannot be ruled out. A variety of other non-malignant effects have been observed after moderate/low dose exposure in various groups, in particular respiratory and digestive disease and central nervous system (and in particular neuro-cognitive) damage. However, because these are generally only observed in isolated groups, or because the evidence is excessively heterogeneous, these associations must be treated with caution. PMID:23903347

Biomarkers of oxidative stress and cataract. Novel drug delivery therapeutic strategies targeting telomere reduction and the expression of telomerase activity in the lens epithelial cells with N-acetylcarnosine lubricant eye drops: anti-cataract which helps to prevent and treat cataracts in the eyes of dogs and other animals.

PubMed

Babizhayev, Mark A; Yegorov, Yegor E

2014-01-01

Cataracts in small animals are shown to be at least partially caused by oxidative damage to lens epithelial cells (LECs) and the internal lens; biomarkers of oxidative stress in the lens are considered as general biomarkers for life expectancy in the canine and other animals. Telomeres lengths and expressed telomerase activity in canine LECs may serve as important monitors of oxidative damage in normal LECs with documented higher levels of telomerase activity in cataractous LECs during cells' lifespan. Loss of functional telomere length below a critical threshold in LECs of canines during the effect of UV and chronic oxidative stress or metabolic failure, can activate programs leading to LEC senescence or death. Telomerase is induced in LECs of canines at critical stages of cataractogenesis initiation and exposure to oxidative stress through the involvement of catalytically active prooxidant transition metal (iron) ions. This work documents that transition metal ions (such as, ferrous ions- catalytic oxidants) might induce premature senescence in LECs of canines, telomere shortening with increased telomerase activity as adaptive response to UV light, oxidative and metabolic stresses. The therapeutic treatment with 1% N-acetylcarnosine (NAC) prodrug delivery is beneficial for prevention and dissolution of ripe cataracts in canines. This biological activity is based on the findings of ferroxidase activity pertinent to the dipeptide carnosine released ophthalmically from NAC prodrug of L-carnosine, stabilizing properties of carnosine on biological membranes based on the ability of the imidazole-containing dipeptides to interact with lipid peroxidation products and reactive oxygen species (ROS), to prevent membrane damage and delute the associated with membrane fragements protein aggregates. The advent of therapeutic treatment of cataracts in canines with N-acetylcarnosine lubricant eye drops through targeting the prevention of loss of functional telomere length below a critical threshold and "flirting" with an indirect effect with telomerase expression in LECs of canines during the effects of UV, chronic oxidative stress increases the successful rate of cataract management challenges in home veterinary care.

Hydrogen saline prevents selenite-induced cataract in rats

PubMed Central

Yang, Chun-xiao; Ding, Tian-bing

2013-01-01

Purpose The aim of this study was to investigate the potential antioxidative effect and mechanism for the protective effects of hydrogen saline on selenite-induced cataract in rats. Methods Sprague-Dawley rat pups were divided into the following groups: control (Group A), selenite induced (Group B), and selenite plus hydrogen saline treated (Group C). Rat pups in Groups B and C received a single subcutaneous injection of sodium selenite (25 μmol/kg bodyweight) on postnatal day 12. Group C also received an intraperitoneal injection of H2 saline (5 ml/kg bodyweight) daily from postnatal day 8 to postnatal day 17. The development of cataract was assessed weekly by slit-lamp examination for 2 weeks. After sacrifice, extricated lenses were analyzed for activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glutathione S-transferase, levels of malondialdehyde, reduced glutathione (GSH), and total sulfhydryl contents. Results The magnitude of lens opacification in Group B was significantly higher than in Group A (p<0.05), while Group C had less opacification than Group B (p<0.05). Compared with Group B, the mean activities of the antioxidant enzymes superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glutathione S-transferase, levels of GSH, and total sulfhydryl contents were higher, whereas the level of malondialdehyde was lower following treatment with hydrogen saline(p<0.05). Conclusions This is an initial report showing that hydrogen saline can prevent selenite-induced cataract in rats. It acts via maintaining antioxidant enzymes and GSH, protecting the sulfhydryl group, and inhibiting lipid peroxidation. PMID:23922487

Pinus densiflora bark extract prevents selenite-induced cataract formation in the lens of Sprague Dawley rat pups.

PubMed

Kim, Jun; Choung, Se-Young

2017-01-01

Rat pups treated with sodium selenite are typically used as an in vivo model to mimic age-related nuclear cataract. Reactive oxygen species (ROS) production, lipid peroxidation, reduction of antioxidant enzymes, crystalline proteolysis, and apoptosis are considered factors that contribute to pathogenesis of age-related nuclear cataract. In the present study, we investigated whether Pinus densiflora bark extract has potential to prevent cataract formation and elucidated the underlying mechanism. Sprague Dawley rats were divided into six groups (n=10). Group 1 rat pups (the control) were treated with only normal saline. The rat pups in groups 2 to 6 were given a subcutaneous injection with sodium selenite (18 μmol/kg bodyweight) on postnatal (P) day 10. Group 3 rat pups (the positive control) were given gastric intubation with curcumin (80 mg/kg bodyweight) on P9, P10, and P11. The rat pups in groups 4 to 6 were given gastric intubation with P. densiflora bark extract 40 mg/kg, 80 mg/kg, and 120 mg/kg, respectively, on P9, P10, and P11. This study showed that P. densiflora bark extract dose-dependently prevented cataract formation. Water-soluble protein, glutathione, superoxide dismutase, glutathione peroxidase, and catalase activity levels were found to be high, and conversely, water-insoluble protein, malondialdehyde, and Ca 2+ -ATPase were found to be low in the groups treated with P. densiflora bark extract compared to group 2. Real-time PCR analysis showed αA-crystalline, lens-specific m-calpain ( Lp84 ), lens-specific intermediates (filensin and phakinin), and antiapoptotic factor ( Bcl-2 ) were downregulated, and the apoptotic factors (caspase-3 and Bax) and plasma membrane Ca 2+ -ATPase ( PMCA-1 ) were upregulated in group 2 compared to group 1. P. densiflora bark extract regulated the imbalance of these genes. The increased cleavage form of caspase-3 was lowered in the groups treated with P. densiflora bark extract. In conclusion, P. densiflora bark extract prevented selenite-induced cataract formation via regulating antioxidant enzymes, inhibiting m -calpain-induced proteolysis, and apoptosis, and thus, maintained the transparency of the lens. These results suggested that P. densiflora bark extract could be a new agent for preventing age-related nuclear cataract.

Dose conversion coefficients for monoenergetic electrons incident on a realistic human eye model with different lens cell populations

NASA Astrophysics Data System (ADS)

Nogueira, P.; Zankl, M.; Schlattl, H.; Vaz, P.

2011-11-01

The radiation-induced posterior subcapsular cataract has long been generally accepted to be a deterministic effect that does not occur at doses below a threshold of at least 2 Gy. Recent epidemiological studies indicate that the threshold for cataract induction may be much lower or that there may be no threshold at all. A thorough study of this subject requires more accurate dose estimates for the eye lens than those available in ICRP Publication 74. Eye lens absorbed dose per unit fluence conversion coefficients for electron irradiation were calculated using a geometrical model of the eye that takes into account different cell populations of the lens epithelium, together with the MCNPX Monte Carlo radiation transport code package. For the cell population most sensitive to ionizing radiation—the germinative cells—absorbed dose per unit fluence conversion coefficients were determined that are up to a factor of 4.8 higher than the mean eye lens absorbed dose conversion coefficients for electron energies below 2 MeV. Comparison of the results with previously published values for a slightly different eye model showed generally good agreement for all electron energies. Finally, the influence of individual anatomical variability was quantified by positioning the lens at various depths below the cornea. A depth difference of 2 mm between the shallowest and the deepest location of the germinative zone can lead to a difference between the resulting absorbed doses of up to nearly a factor of 5000 for electron energy of 0.7 MeV.

Space Radiation Heart Disease Risk Estimates for Lunar and Mars Missions

NASA Technical Reports Server (NTRS)

Cucinotta, Francis A.; Chappell, Lori; Kim, Myung-Hee

2010-01-01

The NASA Space Radiation Program performs research on the risks of late effects from space radiation for cancer, neurological disorders, cataracts, and heart disease. For mortality risks, an aggregate over all risks should be considered as well as projection of the life loss per radiation induced death. We report on a triple detriment life-table approach to combine cancer and heart disease risks. Epidemiology results show extensive heterogeneity between populations for distinct components of the overall heart disease risks including hypertension, ischaemic heart disease, stroke, and cerebrovascular diseases. We report on an update to our previous heart disease estimates for Heart disease (ICD9 390-429) and Stroke (ICD9 430-438), and other sub-groups using recent meta-analysis results for various exposed radiation cohorts to low LET radiation. Results for multiplicative and additive risk transfer models are considered using baseline rates for US males and female. Uncertainty analysis indicated heart mortality risks as low as zero, assuming a threshold dose for deterministic effects, and projections approaching one-third of the overall cancer risk. Medan life-loss per death estimates were significantly less than that of solid cancer and leukemias. Critical research questions to improve risks estimates for heart disease are distinctions in mechanisms at high doses (>2 Gy) and low to moderate doses (<2 Gy), and data and basic understanding of radiation doserate and quality effects, and individual sensitivity.

Cataracts induced by neodymium-yttrium-aluminium-garnet laser lysis of vitreous floaters.

PubMed

Koo, Ellen H; Haddock, Luis J; Bhardwaj, Namita; Fortun, Jorge A

2017-06-01

Neodymium-yttrium-aluminium-garnet (Nd:YAG) laser vitreolysis has been proposed as a treatment modality for symptomatic vitreous floaters. The purpose of this paper is to report two cases of cataracts associated with posterior capsular compromise, induced by Nd:YAG laser vitreolysis for symptomatic vitreous floaters. Case series. Two patients who underwent ND:YAG laser vitreolysis for symptomatic floaters, presented with decline in visual acuity in the treated eye after the laser procedure. At the slit-lamp biomicroscope, each patient was found to have a posterior subcapsular cataract in the treated eye, with obvious loss of integrity of the posterior capsule. These two patients underwent cataract extraction by the same surgeon via phacoemulsification. Both eyes were found to have a defect in the posterior capsule intraoperatively. In both cases, a three-piece acrylic intraocular lens implant was placed in the sulcus, achieving optic capture. The best-corrected visual acuity (BCVA) was 20/20 in both patients, at 1 month following the surgery. At 2 months, one patient had a BCVA of 20/15. The second patient maintained a BCVA of 20/20 at 3 months. Secondary cataract formation accompanied by loss of integrity of the posterior capsule is a potential complication of Nd:YAG laser vitreolysis for symptomatic floaters. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Site specific oxidation of amino acid residues in rat lens γ-crystallin induced by low-dose γ-irradiation.

PubMed

Kim, Ingu; Saito, Takeshi; Fujii, Norihiko; Kanamoto, Takashi; Chatake, Toshiyuki; Fujii, Noriko

2015-10-30

Although cataracts are a well-known age-related disease, the mechanism of their formation is not well understood. It is currently thought that eye lens proteins become abnormally aggregated, initially causing clumping that scatters the light and interferes with focusing on the retina, and ultimately resulting in a cataract. The abnormal aggregation of lens proteins is considered to be triggered by various post-translational modifications, such as oxidation, deamidation, truncation and isomerization, that occur during the aging process. Such modifications, which are also generated by free radical and reactive oxygen species derived from γ-irradiation, decrease crystallin solubility and lens transparency, and ultimately lead to the development of a cataract. In this study, we irradiated young rat lenses with low-dose γ-rays and extracted the water-soluble and insoluble protein fractions. The water-soluble and water-insoluble lens proteins were digested with trypsin, and the resulting peptides were analyzed by LC-MS. Specific oxidation sites of methionine, cysteine and tryptophan in rat water-soluble and -insoluble γE and γF-crystallin were determined by one-shot analysis. The oxidation sites in rat γE and γF-crystallin resemble those previously identified in γC and γD-crystallin from human age-related cataracts. Our study on modifications of crystallins induced by ionizing irradiation may provide useful information relevant to human senile cataract formation. Copyright © 2015 Elsevier Inc. All rights reserved.

Systemic complications of trinitrotoluene (TNT) in exposed workers.

PubMed

Naderi, Mostafa; Ghanei, Mostafa; Shohrati, Majid; Saburi, Amin; Babaei, Mahmoud; Najafian, Bita

2013-03-01

2,4,6-trinitrotoluene (TNT) has been widely used as an explosive. TNT can induce some well-recognized toxic impacts comprising toxic hepatitis, aplastic anemia and cataract. The aim of study was evaluation of TNT exposed workers for systemic complication. In a cross-sectional study, we carried out Liver Function Test (LFT), complete blood count (CBC) and slit lamp biomicroscopy to compare the prevalence and severity of these 3 complications between 47 male TNT exposed workers (with at least one year continuous experience of TNT exposure) and 43 unexposed male hospital worker who hadn't had any previous contacts with TNT. We also performed Pulmonary Function Test (PFT) to assess the probable obstructive/restrictive abnormalities, caused by TNT. Mean alkaline phosphatase (ALP) level of TNT exposed group was significantly higher than the unexposed group (p = 0.023) Forced Expiratory Volume in one second to Forced Vital Capacity (FEV1/FVC) ratios of both groups were in the range of restrictive pattern (82.03% and 81.42% for the exposed and unexposed group, respectively) with no meaningful difference. We didn't find out any specific TNT induced cataract and general cortical cataract (CC) and nuclear sclerotic cataract (NSC) prevalence was not significantly different. we haven't found TNT as a chemical, causing toxic hepatitis or aplastic anemia; neither did we find it as a compound, responsible for a meaningful increase in cataract prevalence. However, due to the increased ALP serum levels and FEV1/FVC ratios among TNT workers, safety precautions are advised.

Ultraviolet radiation, human health, and the urban forest

Treesearch

Gordon M. Heisler; Richard H. Grant

2000-01-01

Excess exposure to ultraviolet (UV) radiation from the sun, particularly the ultraviolet B (UVB) portion, has been linked with adverse effects on human health ranging from skin cancers to eye diseases such as cataracts. Trees may prevent even greater disease rates in humans by reducing UV exposure. Tree shade greatly reduces UV irradiance when both the sun and sky are...

Laser-induced fluorescence spectroscopy of the secondary cataract

NASA Astrophysics Data System (ADS)

Maslov, N. A.; Larionov, P. M.; Rozhin, I. A.; Druzhinin, I. B.; Chernykh, V. V.

2016-06-01

Excitation-emission matrices of laser-induced fluorescence of lens capsule epithelium, the lens nucleus, and the lens capsule are investigated. A solid-state laser in combination with an optical parametric generator tunable in the range from 210 to 350 nm was used for excitation of fluorescence. The spectra of fluorescence of all three types of tissues exhibit typical features that are specific to them and drastically differ from one another. This effect can be used for intrasurgical control of presence of residual lens capsule epithelium cells in the capsular bag after surgical treatment of a cataract.

UVA-UVB photoprotective activity of topical formulations containing Morinda citrifolia extract.

PubMed

Serafini, Mairim Russo; Detoni, Cassia Britto; Menezes, Paula dos Passos; Pereira Filho, Rose Nely; Fortes, Vanessa Silveira; Vieira, Maria José Fonseca; Guterres, Sílvia Stanisçuaski; Cavalcanti de Albuquerque Junior, Ricardo Luiz; Araújo, Adriano Antunes de Souza

2014-01-01

Exposure to solar radiation, particularly its ultraviolet (UV) component, has a variety of harmful effects on human health. Some of these effects include sunburn cell formations, basal and squamous cell cancers, melanoma, cataracts, photoaging of the skin, and immune suppression. The beneficial photoprotective effects of topical formulations with the extract, Morinda citrifolia, have not been investigated. This present study aims to investigate the potential benefits of M. citrifolia topical application on the dorsal skin of mice, exposed to UVA-UVB light. Using 7 days of treatment, [before (baseline values) and 20 h after UV exposure], the thickness, skin barrier damage (TEWL), erythema, and histological alterations were evaluated. The results showed that the formulations containing the extract protected the skin against UV-induced damage.

TU-E-201-02: Eye Lens Dosimetry From CT Perfusion Studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, D.

Madan M. Rehani, Massachusetts General Hospital and Harvard Medical School, Boston Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionalists Radiation induced cataract is a major threat among staff working in interventional suites. Nearly 16 million interventional procedures are performed annually in USA. Recent studies by the principal investigator’s group, primarily among interventional cardiologists, on behalf of the International Atomic Energy Agency, show posterior subcapsular (PSC) changes in the eye lens in 38–53% of main operators and 21–45% of support staff. These changes have potential to lead to cataract in future years, as per information from A-Bombmore » survivors. The International Commission on Radiological Protection has reduced dose limit for staff by a factor of 7.5 (from 150 mSv/y to 20 mSv/y). With increasing emphasis on radiation induced cataracts and reduction in threshold dose for eye lens, there is a need to implement strategies for estimating eye lens dose. Unfortunately eye lens dosimetry is at infancy when it comes to routine application. Various approaches are being tried namely direct measurement using active or passive dosimeters kept close to eyes, retrospective estimations and lastly correlating patient dose in interventional procedures with staff eye dose. The talk will review all approaches available and ongoing active research in this area, as well as data from surveys done in Europe on status of eye dose monitoring in interventional radiology and nuclear medicine. The talk will provide update on how good is Hp(10) against Hp(3), estimations from CTDI values, Monte Carlo based simulations and current status of eye lens dosimetry in USA and Europe. The cataract risk among patients is in CT examinations of the head. Since radiation induced cataract predominantly occurs in posterior sub-capsular (PSC) region and is thus distinguishable from age or drug related cataracts and is also preventable, actions on awareness can lead to avoidance or even prevention. Learning Objectives: To understand recent changes in eye lens dose limits and thresholds for tissue reactions To understand different approaches to dose estimation for eye lens To learn about challenges in eye lens opacities among staff in interventional fluoroscopy Di Zhang, Toshiba America Medical Systems, Tustin, CA, USA Eye lens radiation dose from brain perfusion CT exams CT perfusion imaging requires repeatedly exposing one location of the head to monitor the uptake and washout of iodinated contrast. The accumulated radiation dose to the eye lens can be high, leading to concerns about potential radiation injury from these scans. CTDIvol assumes continuous z coverage and can overestimate eye lens dose in CT perfusion scans where the table do not increment. The radiation dose to the eye lens from clinical CT brain perfusion studies can be estimated using Monte Carlo simulation methods on voxelized patient models. MDCT scanners from four major manufacturers were simulated and the eye lens doses were estimated using the AAPM posted clinical protocols. They were also compared to CTDIvol values to evaluate the overestimation from CTDIvol. The efficacy of eye lens dose reduction techniques such as tilting the gantry and moving the scan location away from the eyelens were also investigated. Eye lens dose ranged from 81 mGy to 279 mGy, depending on the scanner and protocol used. It is between 59% and 63% of the CTDIvol values reported by the scanners. The eye lens dose is significantly reduced when the eye lenses were not directly irradiated. CTDIvol should not be interpreted as patient dose; this study has shown it to overestimate dose to the eye lens. These results may be used to provide more accurate estimates of actual dose to ensure that protocols are operated safely below thresholds. Tilting the gantry or moving the scanning region further away from the eyes are effective for reducing lens dose in clinical practice. These actions should be considered when they are consistent with the clinical task and patient anatomy. Learning Objectives: To become familiar with method of eye dose estimation for patient in specific situation of brain perfusion CT To become familiar with level of eye lens radiation doses in patients undergoing brain perfusion MDCT To understand methods for reducing eye lens dose to patient Jong Min Park, Department of Radiation Oncology, Seoul National University Hospital, Seoul, Korea Eye lens dosimetry in radiotherapy using contact lens-shaped applicator Dose calculation accuracy of commercial treatment planning systems is relatively low at shallow depths. Therefore, in-vivo measurements are often performed in the clinic to verify delivered doses to eye lens which are located at shallow depth. Current in-vivo dosimetry for eye lens during radiotherapy is generally performed with small in-vivo dosimeters on the surface of patient eyelid. Since this procedure potentially contains considerable uncertainty, a contact lens-shaped applicator made of acrylic (lens applicator) was developed for in-vivo measurements of eye lens dose during radiotherapy to reduce uncertainty. The lens applicator allows the insertion of commercially available metal oxide semiconductor field effect transistor (MOSFET) dosimeters. Computed tomography (CT) images of an anthropomorphic phantom with and without the lens applicator were acquired. A total of 20 VMAT plans were delivered to an anthropomorphic phantom and the doses with the lens applicator and the doses at the surface of the eyelid were measured using both micro and standard MOSFET dosimeters. The differences in measured dose at the surface of the eyelid from the calculated lens dose were acquired. The differences between the measured and the calculated doses at the lens applicator, as well as the differences between the measured and the calculated doses at the surface of the eyelid were acquired. The statistical significance of the differences was analyzed. The average difference between the measured and the calculated dose with the lens applicator was 16.8 % ± 10.4 % with a micro MOSFET dosimeter and 16.6 % ± 10.9% with a standard MOSFET dosimeter. The average difference without the lens applicator was 35.9% ± 41.5% with micro MOSFET dosimeter and 42.9% ± 52.2% with standard MOSFET dosimeter. The maximum difference with micro MOSFET dosimeter was 46% with the applicator and 188.4% without the applicator. For the standard MOSFET dosimeter, the maximum difference was 44.4% with the applicator and 246.4% without the applicator. The lens applicator allowed reduction of the differences between the calculated and the measured dose during in-vivo measurement for the eye lens as compared to in-vivo measurement at the surface of the eyelid. Learning Objectives: To understand limitations of dose calculation with commercial treatment planning system for eye lens during radiotherapy To learn about current in-vivo dosimetry methods for eye lens in the clinic To understand limitations of in-vivo dosimetry for eye lens during radiotherapy Di Zhang is an employee of Toshiba America Medical Systems.« less

TU-E-201-03: Eye Lens Dosimetry in Radiotherapy Using Contact Lens-Shaped Applicator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Park, J.

Madan M. Rehani, Massachusetts General Hospital and Harvard Medical School, Boston Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionalists Radiation induced cataract is a major threat among staff working in interventional suites. Nearly 16 million interventional procedures are performed annually in USA. Recent studies by the principal investigator’s group, primarily among interventional cardiologists, on behalf of the International Atomic Energy Agency, show posterior subcapsular (PSC) changes in the eye lens in 38–53% of main operators and 21–45% of support staff. These changes have potential to lead to cataract in future years, as per information from A-Bombmore » survivors. The International Commission on Radiological Protection has reduced dose limit for staff by a factor of 7.5 (from 150 mSv/y to 20 mSv/y). With increasing emphasis on radiation induced cataracts and reduction in threshold dose for eye lens, there is a need to implement strategies for estimating eye lens dose. Unfortunately eye lens dosimetry is at infancy when it comes to routine application. Various approaches are being tried namely direct measurement using active or passive dosimeters kept close to eyes, retrospective estimations and lastly correlating patient dose in interventional procedures with staff eye dose. The talk will review all approaches available and ongoing active research in this area, as well as data from surveys done in Europe on status of eye dose monitoring in interventional radiology and nuclear medicine. The talk will provide update on how good is Hp(10) against Hp(3), estimations from CTDI values, Monte Carlo based simulations and current status of eye lens dosimetry in USA and Europe. The cataract risk among patients is in CT examinations of the head. Since radiation induced cataract predominantly occurs in posterior sub-capsular (PSC) region and is thus distinguishable from age or drug related cataracts and is also preventable, actions on awareness can lead to avoidance or even prevention. Learning Objectives: To understand recent changes in eye lens dose limits and thresholds for tissue reactions To understand different approaches to dose estimation for eye lens To learn about challenges in eye lens opacities among staff in interventional fluoroscopy Di Zhang, Toshiba America Medical Systems, Tustin, CA, USA Eye lens radiation dose from brain perfusion CT exams CT perfusion imaging requires repeatedly exposing one location of the head to monitor the uptake and washout of iodinated contrast. The accumulated radiation dose to the eye lens can be high, leading to concerns about potential radiation injury from these scans. CTDIvol assumes continuous z coverage and can overestimate eye lens dose in CT perfusion scans where the table do not increment. The radiation dose to the eye lens from clinical CT brain perfusion studies can be estimated using Monte Carlo simulation methods on voxelized patient models. MDCT scanners from four major manufacturers were simulated and the eye lens doses were estimated using the AAPM posted clinical protocols. They were also compared to CTDIvol values to evaluate the overestimation from CTDIvol. The efficacy of eye lens dose reduction techniques such as tilting the gantry and moving the scan location away from the eyelens were also investigated. Eye lens dose ranged from 81 mGy to 279 mGy, depending on the scanner and protocol used. It is between 59% and 63% of the CTDIvol values reported by the scanners. The eye lens dose is significantly reduced when the eye lenses were not directly irradiated. CTDIvol should not be interpreted as patient dose; this study has shown it to overestimate dose to the eye lens. These results may be used to provide more accurate estimates of actual dose to ensure that protocols are operated safely below thresholds. Tilting the gantry or moving the scanning region further away from the eyes are effective for reducing lens dose in clinical practice. These actions should be considered when they are consistent with the clinical task and patient anatomy. Learning Objectives: To become familiar with method of eye dose estimation for patient in specific situation of brain perfusion CT To become familiar with level of eye lens radiation doses in patients undergoing brain perfusion MDCT To understand methods for reducing eye lens dose to patient Jong Min Park, Department of Radiation Oncology, Seoul National University Hospital, Seoul, Korea Eye lens dosimetry in radiotherapy using contact lens-shaped applicator Dose calculation accuracy of commercial treatment planning systems is relatively low at shallow depths. Therefore, in-vivo measurements are often performed in the clinic to verify delivered doses to eye lens which are located at shallow depth. Current in-vivo dosimetry for eye lens during radiotherapy is generally performed with small in-vivo dosimeters on the surface of patient eyelid. Since this procedure potentially contains considerable uncertainty, a contact lens-shaped applicator made of acrylic (lens applicator) was developed for in-vivo measurements of eye lens dose during radiotherapy to reduce uncertainty. The lens applicator allows the insertion of commercially available metal oxide semiconductor field effect transistor (MOSFET) dosimeters. Computed tomography (CT) images of an anthropomorphic phantom with and without the lens applicator were acquired. A total of 20 VMAT plans were delivered to an anthropomorphic phantom and the doses with the lens applicator and the doses at the surface of the eyelid were measured using both micro and standard MOSFET dosimeters. The differences in measured dose at the surface of the eyelid from the calculated lens dose were acquired. The differences between the measured and the calculated doses at the lens applicator, as well as the differences between the measured and the calculated doses at the surface of the eyelid were acquired. The statistical significance of the differences was analyzed. The average difference between the measured and the calculated dose with the lens applicator was 16.8 % ± 10.4 % with a micro MOSFET dosimeter and 16.6 % ± 10.9% with a standard MOSFET dosimeter. The average difference without the lens applicator was 35.9% ± 41.5% with micro MOSFET dosimeter and 42.9% ± 52.2% with standard MOSFET dosimeter. The maximum difference with micro MOSFET dosimeter was 46% with the applicator and 188.4% without the applicator. For the standard MOSFET dosimeter, the maximum difference was 44.4% with the applicator and 246.4% without the applicator. The lens applicator allowed reduction of the differences between the calculated and the measured dose during in-vivo measurement for the eye lens as compared to in-vivo measurement at the surface of the eyelid. Learning Objectives: To understand limitations of dose calculation with commercial treatment planning system for eye lens during radiotherapy To learn about current in-vivo dosimetry methods for eye lens in the clinic To understand limitations of in-vivo dosimetry for eye lens during radiotherapy Di Zhang is an employee of Toshiba America Medical Systems.« less

TU-E-201-00: Eye Lens Dosimetry for Patients and Staff

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

Madan M. Rehani, Massachusetts General Hospital and Harvard Medical School, Boston Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionalists Radiation induced cataract is a major threat among staff working in interventional suites. Nearly 16 million interventional procedures are performed annually in USA. Recent studies by the principal investigator’s group, primarily among interventional cardiologists, on behalf of the International Atomic Energy Agency, show posterior subcapsular (PSC) changes in the eye lens in 38–53% of main operators and 21–45% of support staff. These changes have potential to lead to cataract in future years, as per information from A-Bombmore » survivors. The International Commission on Radiological Protection has reduced dose limit for staff by a factor of 7.5 (from 150 mSv/y to 20 mSv/y). With increasing emphasis on radiation induced cataracts and reduction in threshold dose for eye lens, there is a need to implement strategies for estimating eye lens dose. Unfortunately eye lens dosimetry is at infancy when it comes to routine application. Various approaches are being tried namely direct measurement using active or passive dosimeters kept close to eyes, retrospective estimations and lastly correlating patient dose in interventional procedures with staff eye dose. The talk will review all approaches available and ongoing active research in this area, as well as data from surveys done in Europe on status of eye dose monitoring in interventional radiology and nuclear medicine. The talk will provide update on how good is Hp(10) against Hp(3), estimations from CTDI values, Monte Carlo based simulations and current status of eye lens dosimetry in USA and Europe. The cataract risk among patients is in CT examinations of the head. Since radiation induced cataract predominantly occurs in posterior sub-capsular (PSC) region and is thus distinguishable from age or drug related cataracts and is also preventable, actions on awareness can lead to avoidance or even prevention. Learning Objectives: To understand recent changes in eye lens dose limits and thresholds for tissue reactions To understand different approaches to dose estimation for eye lens To learn about challenges in eye lens opacities among staff in interventional fluoroscopy Di Zhang, Toshiba America Medical Systems, Tustin, CA, USA Eye lens radiation dose from brain perfusion CT exams CT perfusion imaging requires repeatedly exposing one location of the head to monitor the uptake and washout of iodinated contrast. The accumulated radiation dose to the eye lens can be high, leading to concerns about potential radiation injury from these scans. CTDIvol assumes continuous z coverage and can overestimate eye lens dose in CT perfusion scans where the table do not increment. The radiation dose to the eye lens from clinical CT brain perfusion studies can be estimated using Monte Carlo simulation methods on voxelized patient models. MDCT scanners from four major manufacturers were simulated and the eye lens doses were estimated using the AAPM posted clinical protocols. They were also compared to CTDIvol values to evaluate the overestimation from CTDIvol. The efficacy of eye lens dose reduction techniques such as tilting the gantry and moving the scan location away from the eyelens were also investigated. Eye lens dose ranged from 81 mGy to 279 mGy, depending on the scanner and protocol used. It is between 59% and 63% of the CTDIvol values reported by the scanners. The eye lens dose is significantly reduced when the eye lenses were not directly irradiated. CTDIvol should not be interpreted as patient dose; this study has shown it to overestimate dose to the eye lens. These results may be used to provide more accurate estimates of actual dose to ensure that protocols are operated safely below thresholds. Tilting the gantry or moving the scanning region further away from the eyes are effective for reducing lens dose in clinical practice. These actions should be considered when they are consistent with the clinical task and patient anatomy. Learning Objectives: To become familiar with method of eye dose estimation for patient in specific situation of brain perfusion CT To become familiar with level of eye lens radiation doses in patients undergoing brain perfusion MDCT To understand methods for reducing eye lens dose to patient Jong Min Park, Department of Radiation Oncology, Seoul National University Hospital, Seoul, Korea Eye lens dosimetry in radiotherapy using contact lens-shaped applicator Dose calculation accuracy of commercial treatment planning systems is relatively low at shallow depths. Therefore, in-vivo measurements are often performed in the clinic to verify delivered doses to eye lens which are located at shallow depth. Current in-vivo dosimetry for eye lens during radiotherapy is generally performed with small in-vivo dosimeters on the surface of patient eyelid. Since this procedure potentially contains considerable uncertainty, a contact lens-shaped applicator made of acrylic (lens applicator) was developed for in-vivo measurements of eye lens dose during radiotherapy to reduce uncertainty. The lens applicator allows the insertion of commercially available metal oxide semiconductor field effect transistor (MOSFET) dosimeters. Computed tomography (CT) images of an anthropomorphic phantom with and without the lens applicator were acquired. A total of 20 VMAT plans were delivered to an anthropomorphic phantom and the doses with the lens applicator and the doses at the surface of the eyelid were measured using both micro and standard MOSFET dosimeters. The differences in measured dose at the surface of the eyelid from the calculated lens dose were acquired. The differences between the measured and the calculated doses at the lens applicator, as well as the differences between the measured and the calculated doses at the surface of the eyelid were acquired. The statistical significance of the differences was analyzed. The average difference between the measured and the calculated dose with the lens applicator was 16.8 % ± 10.4 % with a micro MOSFET dosimeter and 16.6 % ± 10.9% with a standard MOSFET dosimeter. The average difference without the lens applicator was 35.9% ± 41.5% with micro MOSFET dosimeter and 42.9% ± 52.2% with standard MOSFET dosimeter. The maximum difference with micro MOSFET dosimeter was 46% with the applicator and 188.4% without the applicator. For the standard MOSFET dosimeter, the maximum difference was 44.4% with the applicator and 246.4% without the applicator. The lens applicator allowed reduction of the differences between the calculated and the measured dose during in-vivo measurement for the eye lens as compared to in-vivo measurement at the surface of the eyelid. Learning Objectives: To understand limitations of dose calculation with commercial treatment planning system for eye lens during radiotherapy To learn about current in-vivo dosimetry methods for eye lens in the clinic To understand limitations of in-vivo dosimetry for eye lens during radiotherapy Di Zhang is an employee of Toshiba America Medical Systems.« less

TU-E-201-01: Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionists

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rehani, M.

Madan M. Rehani, Massachusetts General Hospital and Harvard Medical School, Boston Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionalists Radiation induced cataract is a major threat among staff working in interventional suites. Nearly 16 million interventional procedures are performed annually in USA. Recent studies by the principal investigator’s group, primarily among interventional cardiologists, on behalf of the International Atomic Energy Agency, show posterior subcapsular (PSC) changes in the eye lens in 38–53% of main operators and 21–45% of support staff. These changes have potential to lead to cataract in future years, as per information from A-Bombmore » survivors. The International Commission on Radiological Protection has reduced dose limit for staff by a factor of 7.5 (from 150 mSv/y to 20 mSv/y). With increasing emphasis on radiation induced cataracts and reduction in threshold dose for eye lens, there is a need to implement strategies for estimating eye lens dose. Unfortunately eye lens dosimetry is at infancy when it comes to routine application. Various approaches are being tried namely direct measurement using active or passive dosimeters kept close to eyes, retrospective estimations and lastly correlating patient dose in interventional procedures with staff eye dose. The talk will review all approaches available and ongoing active research in this area, as well as data from surveys done in Europe on status of eye dose monitoring in interventional radiology and nuclear medicine. The talk will provide update on how good is Hp(10) against Hp(3), estimations from CTDI values, Monte Carlo based simulations and current status of eye lens dosimetry in USA and Europe. The cataract risk among patients is in CT examinations of the head. Since radiation induced cataract predominantly occurs in posterior sub-capsular (PSC) region and is thus distinguishable from age or drug related cataracts and is also preventable, actions on awareness can lead to avoidance or even prevention. Learning Objectives: To understand recent changes in eye lens dose limits and thresholds for tissue reactions To understand different approaches to dose estimation for eye lens To learn about challenges in eye lens opacities among staff in interventional fluoroscopy Di Zhang, Toshiba America Medical Systems, Tustin, CA, USA Eye lens radiation dose from brain perfusion CT exams CT perfusion imaging requires repeatedly exposing one location of the head to monitor the uptake and washout of iodinated contrast. The accumulated radiation dose to the eye lens can be high, leading to concerns about potential radiation injury from these scans. CTDIvol assumes continuous z coverage and can overestimate eye lens dose in CT perfusion scans where the table do not increment. The radiation dose to the eye lens from clinical CT brain perfusion studies can be estimated using Monte Carlo simulation methods on voxelized patient models. MDCT scanners from four major manufacturers were simulated and the eye lens doses were estimated using the AAPM posted clinical protocols. They were also compared to CTDIvol values to evaluate the overestimation from CTDIvol. The efficacy of eye lens dose reduction techniques such as tilting the gantry and moving the scan location away from the eyelens were also investigated. Eye lens dose ranged from 81 mGy to 279 mGy, depending on the scanner and protocol used. It is between 59% and 63% of the CTDIvol values reported by the scanners. The eye lens dose is significantly reduced when the eye lenses were not directly irradiated. CTDIvol should not be interpreted as patient dose; this study has shown it to overestimate dose to the eye lens. These results may be used to provide more accurate estimates of actual dose to ensure that protocols are operated safely below thresholds. Tilting the gantry or moving the scanning region further away from the eyes are effective for reducing lens dose in clinical practice. These actions should be considered when they are consistent with the clinical task and patient anatomy. Learning Objectives: To become familiar with method of eye dose estimation for patient in specific situation of brain perfusion CT To become familiar with level of eye lens radiation doses in patients undergoing brain perfusion MDCT To understand methods for reducing eye lens dose to patient Jong Min Park, Department of Radiation Oncology, Seoul National University Hospital, Seoul, Korea Eye lens dosimetry in radiotherapy using contact lens-shaped applicator Dose calculation accuracy of commercial treatment planning systems is relatively low at shallow depths. Therefore, in-vivo measurements are often performed in the clinic to verify delivered doses to eye lens which are located at shallow depth. Current in-vivo dosimetry for eye lens during radiotherapy is generally performed with small in-vivo dosimeters on the surface of patient eyelid. Since this procedure potentially contains considerable uncertainty, a contact lens-shaped applicator made of acrylic (lens applicator) was developed for in-vivo measurements of eye lens dose during radiotherapy to reduce uncertainty. The lens applicator allows the insertion of commercially available metal oxide semiconductor field effect transistor (MOSFET) dosimeters. Computed tomography (CT) images of an anthropomorphic phantom with and without the lens applicator were acquired. A total of 20 VMAT plans were delivered to an anthropomorphic phantom and the doses with the lens applicator and the doses at the surface of the eyelid were measured using both micro and standard MOSFET dosimeters. The differences in measured dose at the surface of the eyelid from the calculated lens dose were acquired. The differences between the measured and the calculated doses at the lens applicator, as well as the differences between the measured and the calculated doses at the surface of the eyelid were acquired. The statistical significance of the differences was analyzed. The average difference between the measured and the calculated dose with the lens applicator was 16.8 % ± 10.4 % with a micro MOSFET dosimeter and 16.6 % ± 10.9% with a standard MOSFET dosimeter. The average difference without the lens applicator was 35.9% ± 41.5% with micro MOSFET dosimeter and 42.9% ± 52.2% with standard MOSFET dosimeter. The maximum difference with micro MOSFET dosimeter was 46% with the applicator and 188.4% without the applicator. For the standard MOSFET dosimeter, the maximum difference was 44.4% with the applicator and 246.4% without the applicator. The lens applicator allowed reduction of the differences between the calculated and the measured dose during in-vivo measurement for the eye lens as compared to in-vivo measurement at the surface of the eyelid. Learning Objectives: To understand limitations of dose calculation with commercial treatment planning system for eye lens during radiotherapy To learn about current in-vivo dosimetry methods for eye lens in the clinic To understand limitations of in-vivo dosimetry for eye lens during radiotherapy Di Zhang is an employee of Toshiba America Medical Systems.« less

Fourier transform infrared spectral evidences for protein conformational changes in immature cataractous human lens capsules accelerated by myopia and/or systemic hypertension

NASA Astrophysics Data System (ADS)

Lin, Shan-Yang; Lee, Shui-Mei; Li, Mei-Jane; Liang, Run-Chu

1997-08-01

The possible changes in protein structures of the cataractous human lens capsules of the immature patients with myopia and/or systemic hypertension have been investigated using Fourier transform infrared (FT-IR) microspectroscopy. Second-derivative and deconvolution methods have been applied to obtain the position of the overlapping components of the amide I band and assign them to different secondary structures. Changes in the protein secondary structure and composition of amide I band were estimated quantitatively from Fourier self-deconvolution and curve fitting algorithms. The results indicate that myopia and/or systemic hypertension were found to significantly modify the protein secondary structure of the cataractous human lens capsules to increase the β-type structure and random coil and decrease the α-helix structure. Myopia-induced conformational change in triple helix structure was more pronounced. In conclusion, myopia and/or systemic hypertension seem to modify the conformation of the protein structures in cataractous human lens capsule to change ionic permeation through lens capsule to accelerate the cataract formation of senile patients.

A Hypothesis on Biological Protection from Space Radiation Through the Use of New Therapeutic Gases

NASA Technical Reports Server (NTRS)

Schoenfeld, Michael P.; Ansari,Rafat R.; Nakao, Atsunori; Wink, David

2011-01-01

Radiation exposure to astronauts could be a significant obstacle for long duration manned space exploration because of current uncertainties regarding the extent of biological effects. Furthermore, concepts for protective shielding also pose a technically challenging issue due to the nature of cosmic radiation and current mass and power constraints with modern exploration technology. The concern regarding exposure to cosmic radiation is the biological damage it induces. As damage is associated with increased oxidative stress, it is important and would be enabling to mitigate and/or prevent oxidative stress prior to the development of clinical symptoms and disease. This paper hypothesizes a "systems biology" approach in which a combination of chemical and biological mitigation techniques are used conjunctively. It proposes using new, therapeutic, medical gases as both chemical radioprotectors for radical scavenging and biological signaling molecules for management of the body s response to exposure. From reviewing radiochemistry of water, biological effects of CO, H2, NO, and H2S gas, and mechanisms of radiation biology, it is concluded that this approach may have great therapeutic potential for radiation exposure. Furthermore, it also appears to have similar potential for curtailing the pathogenesis of other diseases in which oxidative stress has been implicated including, cardiovascular disease, cancer, chronic inflammatory disease, hypertension, ischemia/reperfusion injury, acute respiratory distress syndrome, parkinson s and alzheimer s disease, cataracts, and aging

A Hypothesis on Biological Protection from Space Radiation Through the Use of New Therapeutic Gases as Medical Counter Measures

NASA Technical Reports Server (NTRS)

Schoenfeld, Michael P.; Ansari, Rafat R.; Nakao, Atsunori; Wink, David

2012-01-01

Radiation exposure to astronauts could be a significant obstacle for long duration manned space exploration because of current uncertainties regarding the extent of biological effects. Furthermore, concepts for protective shielding also pose a technically challenging issue due to the nature of cosmic radiation and current mass and power constraints with modern exploration technology. The concern regarding exposure to cosmic radiation is the biological damage it induces. As damage is associated with increased oxidative stress, it is important and would be enabling to mitigate and/or prevent oxidative stress prior to the development of clinical symptoms and disease. This paper hypothesizes a "systems biology" approach in which a combination of chemical and biological mitigation techniques are used conjunctively. It proposes using new, therapeutic, medical gases as both chemical radioprotectors for radical scavenging and biological signaling molecules for management of the body s response to exposure. From reviewing radiochemistry of water, biological effects of CO, H2, NO, and H2S gas, and mechanisms of radiation biology, it is concluded that this approach may have great therapeutic potential for radiation exposure. Furthermore, it also appears to have similar potential for curtailing the pathogenesis of other diseases in which oxidative stress has been implicated including cardiovascular disease, cancer, chronic inflammatory disease, hypertension, ischemia/reperfusion injury, acute respiratory distress syndrome, Parkinson s and Alzheimer s disease, cataracts, and aging.

A Hypothesis on Biological Protection from Space Radiation Through the Use of New Therapeutic Gases

NASA Technical Reports Server (NTRS)

Schoenfeld, Michael P.; Ansari, Rafat R.; Nakao, Atsunori; Wink, David

2011-01-01

Radiation exposure to astronauts could be a significant obstacle for long duration manned space exploration because of current uncertainties regarding the extent of biological effects. Furthermore, concepts for protective shielding also pose a technically challenging issue due to the nature of cosmic radiation and current mass and power constraints with modern exploration technology. The concern regarding exposure to cosmic radiation is the biological damage it induces. As damage is associated with increased oxidative stress, it is important and would be enabling to mitigate and/or prevent oxidative stress prior to the development of clinical symptoms and disease. This paper hypothesizes a "systems biology" approach in which a combination of chemical and biological mitigation techniques are used conjunctively. It proposes using new, therapeutic, medical gases as both chemical radioprotectors for radical scavenging and biological signaling molecules for management of the body s response to exposure. From reviewing radiochemistry of water, biological effects of CO, H2, NO, and H2S gas, and mechanisms of radiation biology, it is concluded that this approach may have great therapeutic potential for radiation exposure. Furthermore, it also appears to have similar potential for curtailing the pathogenesis of other diseases in which oxidative stress has been implicated including cardiovascular disease, cancer, chronic inflammatory disease, hypertension, ischemia/reperfusion injury, acute respiratory distress syndrome, Parkinson s and Alzheimer s disease, cataracts, and aging.

Guidance on radiation dose limits for the lens of the eye: overview of the recommendations in NCRP Commentary No. 26.

PubMed

Dauer, Lawrence T; Ainsbury, Elizabeth A; Dynlacht, Joseph; Hoel, David; Klein, Barbara E K; Mayer, Donald; Prescott, Christina R; Thornton, Raymond H; Vano, Eliseo; Woloschak, Gayle E; Flannery, Cynthia M; Goldstein, Lee E; Hamada, Nobuyuki; Tran, Phung K; Grissom, Michael P; Blakely, Eleanor A

2017-10-01

This review summarizes the conclusions and recommendations of the new National Council on Radiation Protection and Measurements (NCRP) Commentary No. 26 guidance on radiation dose limits for the lens of the eye. The NCRP addressed radiation protection principles in respect to the lens of the eye, discussed the current understanding of eye biology and lens effects, reviewed and evaluated epidemiology, and assessed exposed populations with the potential for significant radiation exposures to the lens while suggesting monitoring and protection practices. Radiation-induced damage to the lens of the eye can include the loss of clarity resulting in opacification or clouding several years after exposure. The impact is highly dependent on the type of radiation, how the exposure of the lens was delivered, the genetic susceptibilities of the individual exposed, and the location of the opacity relative to the visual axis of the individual. The preponderance of epidemiological evidence suggests that lens damage could occur at lower doses than previously considered and the NCRP has determined that it is prudent to reduce the recommended annual lens of the eye occupational dose limit from an equivalent dose of 150 mSv to an absorbed dose of 50 mGy. Significant additional research is still needed in the following areas: comprehensive evaluation of the overall effects of ionizing radiation on the eye, dosimetry methodology and dose-sparing optimization techniques, additional high quality epidemiology studies, and a basic understanding of the mechanisms of cataract development.

Long term followup of cataracts in children after renal transplantation.

PubMed Central

Wilson, W A; Fine, R N

1979-01-01

In reviewing the course of 218 renal transplantation recipients 55% have developed PSC of which eleven patients have had surgery on one or both eyes; The operations in general have been uncomplicated, and the visual results have been excellent with the exception of one case that had a detached retina. The cataracts were probably induced by heavy corticosteroid therapy as the larger the dosage and the younger the recipient, the more prone were they to the development of lens changes. Phacoemulsification was preferred in this series as the more expeditious technique, leading to a clearer anterior chamber with less chance of developing a secondary cataract. Images FIGURE 1 FIGURE 2 PMID:397659

Ursodeoxycholic acid prevents selenite-induced oxidative stress and alleviates cataract formation: In vitro and in vivo studies

PubMed Central

Qi, Hui-Ping; Wei, Shu-Qin; Gao, Xiang-Chun; Yu, Nan-Nan; Hu, Wan-Zhen; Bi, Sheng

2012-01-01

Objective To evaluate the antioxidative and anticataractogenic potential effect of ursodeoxycholic acid (UDCA) on selenite-induced cataract in vitro and in vivo. Methods Enucleated rat lenses were incubated in M199 medium alone (Group I), with 200 μM selenite (Group II), or with 200 μM selenite and 500 μM UDCA (Group III). Selenite was administered on the third day and UDCA treatment was from the second to the fifth day. The development of cataracts was observed under an inverted microscope. Total antioxidative capabilities (T-AOC), mean activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (Gpx), glutathione reductase (GR) and glutathione S-transferase (GST), levels of reduced glutathione (GSH), malondialdehyde (MDA), and total sulfhydryl content were analyzed in lenticular samples. In vivo, cataracts were induced in 12-day-old pups by single subcutaneous injections of sodium selenite. The test groups received 180 mg/kg bodyweight/day of UDCA intraperitoneally on postpartum days 11–16 or 0.5% UDCA drops four times daily on postpartum days 11–25. Results In vitro, morphological examination of the lenses revealed dense vacuolization and opacification in Group II, minimal vacuolization in 12.5% of Group III, and no opacification in 87.5% of Group III. In Group I, all lenses were clear. UDCA significantly (p<0.05) restored GSH and total sulfhydryl, and decreased MDA levels. T-AOC and the mean activities of the antioxidant enzymes were elevated following treatment with UDCA. In vivo, 0.5% UDCA drops resulted in only 20% nuclear cataract development and 180 mg/kg of UDCA intraperitoneally led to 50% development, compared to 100% in the control group (p<0.05). Conclusions UDCA prevents selenite toxicity and cataractogenesis by maintaining antioxidant status and GSH, protecting the sulfhydryl group, and inhibiting lipid peroxidation in lenses. PMID:22275806

Dual function of TGFβ in lens epithelial cell fate: implications for secondary cataract

PubMed Central

Boswell, Bruce A.; Korol, Anna; West-Mays, Judith A.; Musil, Linda S.

2017-01-01

The most common vision-disrupting complication of cataract surgery is posterior capsule opacification (PCO; secondary cataract). PCO is caused by residual lens cells undergoing one of two very different cell fates: either transdifferentiating into myofibroblasts or maturing into lens fiber cells. Although TGFβ has been strongly implicated in lens cell fibrosis, the factors responsible for the latter process have not been identified. We show here for the first time that TGFβ can induce purified primary lens epithelial cells within the same culture to undergo differentiation into either lens fiber cells or myofibroblasts. Marker analysis confirmed that the two cell phenotypes were mutually exclusive. Blocking the p38 kinase pathway, either with direct inhibitors of the p38 MAP kinase or a small-molecule therapeutic that also inhibits the activation of p38, prevented TGFβ from inducing epithelial–myofibroblast transition and cell migration but did not prevent fiber cell differentiation. Rapamycin had the converse effect, linking MTOR signaling to induction of fiber cell differentiation by TGFβ. In addition to providing novel potential therapeutic strategies for PCO, our findings extend the so-called TGFβ paradox, in which TGFβ can induce two disparate cell fates, to a new epithelial disease state. PMID:28209733

Influence of galactose cataract on erythrocytic and lenticular glutathione metabolism in albino rats.

PubMed

Jyothi, M; Sanil, R; Shashidhar, S

2011-01-01

Glutathione depletion has been postulated to be the prime reason for galactose cataract. The current research seeks the prospect of targeting erythrocytes to pursue the lens metabolism by studying the glutathione system. To study the activity of the glutathione-linked scavenger enzyme system in the erythrocyte and lens of rats with cataract. Experiments were conducted in 36 male albino rats weighing 80 ± 20 g of 28 days of age. The rats were divided into two major groups, viz. experimental and control. Six rats in each group were sacrificed every 10 days, for 30 days. Cataract was induced in the experimental group by feeding the rats 30% galactose (w/w). The involvement of reduced glutathione (GSH) and the linked enzymes was studied in the erythrocytes and lens of cataractous as well as control rats. Parametric tests like one-way ANOVA and Student's 't' test were used for comparison. Correlation linear plot was used to compare the erythrocyte and lens metabolism. The concentration of GSH and the activity of linked enzymes were found decreased with the progression of cataract, and also in comparison to the control. The same linear fashion was also observed in the erythrocytes. Depletion of GSH was the prime factor for initiating galactose cataract in the rat model. This depletion may in turn result in enzyme inactivation leading to cross-linking of protein and glycation. The correlation analysis specifies that the biochemical mechanism in the erythrocytes and lens is similar in the rat model.

Effect of 5-S-GAD on UV-B-induced cataracts in rats.

PubMed

Kawada, Hiroyoshi; Kojima, Masami; Kimura, Takahito; Natori, Shunji; Sasaki, Kazuyuki; Sasaki, Hiroshi

2009-09-01

5-S-Glutathionyl-N-beta-alanyl-3,4-dihydroxyphenylalanine (5-S-GAD) is a novel antibacterial substance purified from Sarcophaga peregrina (flesh fly) that has both a radical scavenging activity and antioxidative activity. This is a report of an investigation of the effect of 5-S-GAD (eyedrops) on UVB-induced cataracts in rats. Brown Norway male rats (n = 32; 7 weeks old) were treated with either 5-S-GAD 0.1%, 5-SGAD 1%, astaxanthin (AST) 0.1% suspension eyedrops or the vehicle alone (the solution without 5-S-GAD) three times a day (three doses at 5-min intervals each time). The treatment was scheduled 2 days before UV-B exposure and 2 days after UV-B exposure. Exposure to 100-200 mJ/cm(2) UV-B was performed once a week between drug treatments for 9 consecutive weeks, with a total dose of 1200 mJ/cm(2) UV-B. Ocular penetration of 5-S-GAD was analyzed using high-pressure liquid chromatography (HPLC). Cataract formation was documented by an anterior eye segment analysis system once a week under mydriasis. The light-scattering intensity (LSI) of the anterior superficial cortex region was measured. In the eighth to ninth week after the start of UV-B exposure, the LSI of anterior subcapsular lenses of 5-S-GAD-treated groups, as detected by HPLC, was significantly lower (P < 0.05) than that of the control, whereas no such difference was found in the AST-treated group. 5-S-GAD eyedrop application may delay the progression of UV-B-induced cataract in rats.

Late biological effects of heavy charged particles: Cataracts, vascular injury and life shortening in mice

NASA Astrophysics Data System (ADS)

Ainsworth, E. J.; Jose, J. G.; Barker, M. E.; Alpen, E. L.

1980-07-01

Risks associated with extended habitation in a space environment, particularly hazards to space workers that might result from exposure to high energy heavy ion particles (HZE), were studied. Biological effects of HZE were investigated in mice to assess their potential adverse health hazards. The potential effects of HZE particles on the crystalline lens of the eye and the carcinogenic effects and blood vessel (vascular) damage from radiation were evaluated by a risk assessment. Animal experiments to evaluate dose response relationships for tumor induction/promotion and for vascular injury were introduced. Cataract productions and preliminary results on cacinogenic and vascular effects are presented for perspective.

Late biological effects of heavy charged particles: Cataracts, vascular injury and life shortening in mice

NASA Technical Reports Server (NTRS)

Ainsworth, E. J.; Jose, J. G.; Barker, M. E.; Alpen, E. L.

1980-01-01

Risks associated with extended habitation in a space environment, particularly hazards to space workers that might result from exposure to high energy heavy ion particles (HZE), were studied. Biological effects of HZE were investigated in mice to assess their potential adverse health hazards. The potential effects of HZE particles on the crystalline lens of the eye and the carcinogenic effects and blood vessel (vascular) damage from radiation were evaluated by a risk assessment. Animal experiments to evaluate dose response relationships for tumor induction/promotion and for vascular injury were introduced. Cataract productions and preliminary results on cacinogenic and vascular effects are presented for perspective.

Regulation of Electromagnetic Radiation: A Confusing Course through Modulating E and H Waves.

DTIC Science & Technology

1982-02-15

29 Biological Effects of RFR: Clinical Findings ......... 30 Cataract ........... . o . o ....... o 30 Psychological Effects...Claims Act alleges injuries to a contractor employee conducting tests of potential effects of electromagnetic pulse radiation on a Minuteman missile site...absorption is the position of the receiving object (e.g. human being, animal or simulated model test subject) relative to the E, H or K planes (K is a

Non-Invasive Early Detection and Molecular Analysis of Low X-ray Dose Effects in the Lens

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goldstein, Lee

This is the Final Progress Report for DOE-funded research project DE-PS02-08ER08-01 titled “Non-Invasive Early Detection and Molecular Analysis of Low X-ray Dose Effects in the Lens”. The project focuses on the effects of low-linear energy transfer (LET) radiation on the ocular lens. The lens is an exquisitely radiosensitive tissue with a highly-ordered molecular structure that is amenable to non-invasive optical study from the periphery. These merits point to the lens as an ideal target for laser-based molecular biodosimetry (MBD). Following exposure to different types of ionizing radiations, the lens demonstrates molecular changes (e.g., oxidation, racemization, crosslinkage, truncation, aggregation, etc.) thatmore » impact the structure and function of the long-lived proteins in the cytosol of lens fiber cells. The vast majority of proteins in the lens comprise the highly-ordered crystallins. These highly conserved lens proteins are amongst the most concentrated and stable in the body. Once synthesized, the crystallins are retained in the fiber cell cytoplasm for life. Taken together, these properties point to the lens as an ideal system for quantitative in vivo MBD assessment using quasi-elastic light scattering (QLS) analysis. In this project, we deploy a purpose-designed non-invasive infrared laser QLS instrument as a quantitative tool for longitudinal assessment of pre-cataractous molecular changes in the lenses of living mice exposed to low-dose low-LET radiation compared to non-irradiated sham controls. We hypothesize that radiation exposure will induce dose-dependent changes in the molecular structure of matrix proteins in the lens. Mechanistic assays to ascertain radiation-induced molecular changes in the lens focus on protein aggregation and gene/protein expression patterns. We anticipate that this study will contribute to our understanding of early molecular changes associated with radiation-induced tissue pathology. This study also affords potential for translational development of molecular biodosimetry instrumentation to assess human exposure to mixed radiation fields.« less

UVA-UVB Photoprotective Activity of Topical Formulations Containing Morinda citrifolia Extract

PubMed Central

Serafini, Mairim Russo; Detoni, Cassia Britto; Menezes, Paula dos Passos; Pereira Filho, Rose Nely; Fortes, Vanessa Silveira; Vieira, Maria José Fonseca; Guterres, Sílvia Stanisçuaski; de Albuquerque Junior, Ricardo Luiz Cavalcanti; Araújo, Adriano Antunes de Souza

2014-01-01

Exposure to solar radiation, particularly its ultraviolet (UV) component, has a variety of harmful effects on human health. Some of these effects include sunburn cell formations, basal and squamous cell cancers, melanoma, cataracts, photoaging of the skin, and immune suppression. The beneficial photoprotective effects of topical formulations with the extract, Morinda citrifolia, have not been investigated. This present study aims to investigate the potential benefits of M. citrifolia topical application on the dorsal skin of mice, exposed to UVA-UVB light. Using 7 days of treatment, [before (baseline values) and 20 h after UV exposure], the thickness, skin barrier damage (TEWL), erythema, and histological alterations were evaluated. The results showed that the formulations containing the extract protected the skin against UV-induced damage. PMID:25133171

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goda, Jayant Sastri; Le, Lisa W.; Lapperriere, Normand J.

Purpose: To evaluate the clinical outcomes and late effects of radiation therapy (RT) in localized primary orbital mucosa-associated lymphoma tissue (MALT) lymphoma (POML). Methods and Materials: From 1989 to 2007, 89 patients with Stage IE POML received RT. The median age was 56 years old. Sites involved conjunctiva (59 patients [66%]), lacrimal gland (20 patients [23%]), and soft tissue (10 patients [11%]). Megavoltage beam(s) was used in 91%, electrons in 7%, and orthovoltage in 2% of cases. The dose given was 25 Gy in 97% and 30 Gy in 3% of patients. Lens shielding was possible in 57% of patients.more » Results: The median follow-up was 5.9 years. Complete response or unconfirmed complete response was seen in 88 patients (99%). Relapse occurred in 22 patients (25%). First relapse sites were local (2 patients [9%]), in the contralateral orbit (5 patients [23%]), and distant (15 patients [68%]). The 7-year overall survival (OS), cause-specific survival (CSS), relapse-free survival (RFS), and local control (LC) rates were 91%, 96%, 64%, and 97%, respectively. Radiation-related late sequelae were documented in 40 patients (45%). Cataracts were observed in 22 patients (Grade 1 in 2 patients; Grade 3 in 20 patients). The incidence of Grade 3 cataract at 7 years was 25%. Other late sequelae (n = 28) were dry eye(s) (22 patients [Grade 1 in 14 patients; Grade 2 in 2 patients; Grade 3 in 2 patients; n/s in 4 patients), keratitis (3 patients), macular degeneration/cystoid edema (2 patients), and vitreous detachment (1 patient). Five patients developed Grade 3 noncataract late effects. Lens shielding reduced the incidence of Grade 3 cataract and all Grade {>=}2 late sequelae. Seventeen patients (16 with cataracts) underwent surgery; 23 patients were treated conservatively. The outcome for managing late effects was generally successful, with 30 patients completely improved, and 9 patients with persisting late sequelae (10%). Conclusions: POML responds favorably to moderate doses of RT but results in significant late morbidity. The majority of late effects were successfully managed. Lens shielding reduced the risk of cataracts and other late sequelae.« less

Modifiers of radiation effects in the eye

NASA Astrophysics Data System (ADS)

Kleiman, Norman J.; Stewart, Fiona A.; Hall, Eric J.

2017-11-01

World events, including the threat of radiological terrorism and the fear of nuclear accidents, have highlighted an urgent need to develop medical countermeasures to prevent or reduce radiation injury. Similarly, plans for manned spaceflight to a near-Earth asteroid or journey to Mars raise serious concerns about long-term effects of space radiation on human health and the availability of suitable therapeutic interventions. At the same time, the need to protect normal tissue from the deleterious effects of radiotherapy has driven considerable research into the design of effective radioprotectors. For more than 70 years, animal models of radiation cataract have been utilized to test the short and long-term efficacy of various radiation countermeasures. While some compounds, most notably the Walter Reed (WR) class of radioprotectors, have reported limited effectiveness when given before exposure to low-LET radiation, the human toxicity of these molecules at effective doses limits their usefulness. Furthermore, while there has been considerable testing of eye responses to X- and gamma irradiation, there is limited information about using such models to limit the injurious effects of heavy ions and neutrons on eye tissue. A new class of radioprotector molecules, including the sulfhydryl compound PrC-210, are reported to be effective at much lower doses and with far less side effects. Their ability to modify ocular radiation damage has not yet been examined. The ability to non-invasively measure sensitive, radiation-induced ocular changes over long periods of time makes eye models an attractive option to test the radioprotective and radiation mitigating abilities of new novel compounds.

Evident Biological Effects of Space Radiation in Astronauts

NASA Technical Reports Server (NTRS)

Wu, Honglu

2004-01-01

Though cancer risks are the primary concern for astronauts exposed to space radiation and a number of astronauts have developed cancer, identifying a direct association or cause of disease has been somewhat problematic due to a lack of statistics and a lack of an appropriate control group. However, several bio,logical effects observed in astronauts are believed to be primarily due to exposure to space radiation. Among those are, light flashes experienced by astronauts from early missions, cataract development in the crewmembers and excess chromosome aberrations detected in astronauts' lymphocytes postmission. The space radiation environment and evident biological effects will be discussed.

Combined Effects of Gamma Radiation and High Dietary Iron on Peripheral Leukocyte Distribution and Function

NASA Technical Reports Server (NTRS)

Crucian, Brian E.; Morgan, Jennifer L. L.; Quiriarte, Heather A.; Sams, Clarence F.; Smith, Scott M.; Zwart, Sara R.

2012-01-01

Both radiation and increased iron stores can independently increase oxidative damage, resulting in protein, lipid and DNA oxidation. Oxidative stress increases the risk of many health problems including cancer, cataracts, and heart disease. This study, a subset of a larger interdisciplinary investigation of the combined effect of iron overload on sensitivity to radiation injury, monitored immune parameters in the peripheral blood of rats subjected to gamma radiation, high dietary iron or both. Specific immune measures consisted of: (1) peripheral leukocyte distribution, (2) plasma cytokine levels and (3) cytokine production profiles following whole blood mitogenic stimulation

Space Radiation and its Associated Health Consequences

NASA Technical Reports Server (NTRS)

Wu, Honglu

2007-01-01

During space travel, astronauts are exposed to energetic particles of a complex composition and energy distribution. For the same amount of absorbed dose, these particles can be much more effective than X- or gamma rays in the induction of biological effects, including cell inactivation, genetic mutations, cataracts, and cancer induction. Several of the biological consequences of space radiation exposure have already been observed in astronauts. This presentation will introduce the space radiation environment and discuss its associated health risks. Accurate assessment of the radiation risks and development of respective countermeasures are essential for the success of future exploration missions to the Moon and Mars.

Quantitative microlocalization of diffusible ions in normal and galactose cataractous rat lens by secondary ion mass spectrometry.

PubMed

Burns, M S; File, D M

1986-11-01

Secondary ion mass spectrometry (SIMS) is a surface analytical technique with high sensitivity for elemental detection and microlocalization capabilities within the micrometre range. Quantitative analysis of epoxy resins and gelatin have been reported (Burns-Bellhorn & File, 1979). We report here the first application of this technique to quantitative microlocalization in the context of a physiological problem--analyses of sodium, potassium and calcium in normal and galactose-induced cataract in rat lens. It is known that during the development of galactose-induced cataract the whole lens content of potassium is decreased, sodium is increased and, in late stages, calcium concentration increases. Whether these alterations in diffusible ions occur homogeneously or heterogeneously is not known. Standard curves were generated from epoxy resins containing known concentrations of sodium, potassium or calcium organometallic compounds using the Cameca IMS 300 Secondary Ion Mass Spectrometer. Normal and cataractous lenses were prepared by freezing in isopentane in a liquid nitrogen bath followed by freeze-drying at -30 degrees C. After dry embedding in epoxy resin, 10 microns thick sections of lens were pressure mounted on silicon wafers, overcoated with gold, and ion emission measured under the same instrumental conditions used to obtain the standard curves. Quantitative analysis of an area 27 microns in diameter, or a total analysed volume of 1.1 microns3, was performed by using a mechanical aperture in the ion optical system. Ion images provided qualitative microanalysis with a lateral resolution of 1 micron. Control rat lenses gave values for sodium and potassium content with a precision of +/- 17% or less. These values were compared to flame photometry and atomic absorption measurements of normal lenses and were accurate within 25%. Analysis of serum and blood also gave accurate and precise measurements of these elements. Normal rat lenses had a gradient of sodium, and, to a lesser degree, of potassium from the cortex to the nucleus. Development of galactose-induced cataract was heterogeneous by morphological criteria, beginning at the lens equator and spreading from the cortex into the nucleus. However, the loss of potassium and increase in sodium concentration occurred at early stages in both the cortex and nucleus cells, possibly because these cells are interconnected by gap junctions. There is a local alteration in elemental content prior to morphologically demonstrable cataract formation.(ABSTRACT TRUNCATED AT 400 WORDS)

Surgical management and histologic and immunohistochemical features of a cataract and retrolental plaque secondary to persistent hyperplastic tunica vasculosa lentis/persistent hyperplastic primary vitreous (PHTVL/PHPV) in a Bloodhound puppy.

PubMed

Gemensky-Metzler, Anne J; Wilkie, David A

2004-01-01

The objective of this study was to describe the clinical, histologic and immunohistochemical features, the surgical treatment, and outcome of a cataract secondary to persistent hyperplastic tunica vasculosa lentis/persistent hyperplastic primary vitreous (PHTVL/PHPV) in a dog. A 4-month-old male Bloodhound dog presented for evaluation of a cataract. A complete ophthalmic examination and ocular ultrasonography were performed. A resorbing cataract with intralenticular hemorrhage, lens induced uveitis, and PHTVL/PHPV were diagnosed. Extracapsular cataract extraction using phacoemulsification was performed. A primary posterior capsulectomy was performed to remove a retrolental plaque with the posterior capsule; the excised plaque was submitted for histopathology and immunohistochemical staining. A 41-Diopter intraocular lens (IOL) was implanted. Functional vision was maintained postoperatively during the 21-month follow-up period. Histologically, the posterior capsule was coiled and exhibited duplication. The retrolental plaque was comprised of dense fibrous connective tissue, blood vessels, free red blood cells, hemosiderin-laden macrophages, a pocket of neural tissue and numerous perivascular mast cells. With immunohistochemical staining, the neural elements were determined to be glial cells compatible with astrocytes. Cataract secondary to PHTVL/PHPV can be successfully treated using phacoemulsification and planned posterior capsulectomy. Posterior lens capsule duplication, mast cells and astrocytic glial cells may be normal components of the fibrovascular retrolental plaque associated with PHTVL/PHPV.

Dominant ER Stress-Inducing WFS1 Mutations Underlie a Genetic Syndrome of Neonatal/Infancy-Onset Diabetes, Congenital Sensorineural Deafness, and Congenital Cataracts.

PubMed

De Franco, Elisa; Flanagan, Sarah E; Yagi, Takuya; Abreu, Damien; Mahadevan, Jana; Johnson, Matthew B; Jones, Garan; Acosta, Fernanda; Mulaudzi, Mphele; Lek, Ngee; Oh, Vera; Petz, Oliver; Caswell, Richard; Ellard, Sian; Urano, Fumihiko; Hattersley, Andrew T

2017-07-01

Neonatal diabetes is frequently part of a complex syndrome with extrapancreatic features: 18 genes causing syndromic neonatal diabetes have been identified to date. There are still patients with neonatal diabetes who have novel genetic syndromes. We performed exome sequencing in a patient and his unrelated, unaffected parents to identify the genetic etiology of a syndrome characterized by neonatal diabetes, sensorineural deafness, and congenital cataracts. Further testing was performed in 311 patients with diabetes diagnosed before 1 year of age in whom all known genetic causes had been excluded. We identified 5 patients, including the initial case, with three heterozygous missense mutations in WFS1 (4/5 confirmed de novo). They had diabetes diagnosed before 12 months (2 before 6 months) (5/5), sensorineural deafness diagnosed soon after birth (5/5), congenital cataracts (4/5), and hypotonia (4/5). In vitro studies showed that these WFS1 mutations are functionally different from the known recessive Wolfram syndrome-causing mutations, as they tend to aggregate and induce robust endoplasmic reticulum stress. Our results establish specific dominant WFS1 mutations as a cause of a novel syndrome including neonatal/infancy-onset diabetes, congenital cataracts, and sensorineural deafness. This syndrome has a discrete pathophysiology and differs genetically and clinically from recessive Wolfram syndrome. © 2017 by the American Diabetes Association.

Protective effects of Cassia tora leaves in experimental cataract by modulating intracellular communication, membrane co-transporters, energy metabolism and the ubiquitin-proteasome pathway.

PubMed

Sreelakshmi, V; Abraham, Annie

2017-12-01

Cataract is the clouding of eye lens which causes impairment in vision and accounts for the leading factor of global blindness. Functional food-based prevention of cataract finds application in vision research because of its availability and easy access to all classes of the society. Cassia tora Linn. (Caesalpinaceae) is an edible plant mentioned in the traditional systems of medicine for whole body health, especially to the eyes. The present study evaluates the potential of ethyl acetate fraction of Cassia tora leaves (ECT) on experimental cataract. Cataract was induced by a single subcutaneous injection of sodium selenite (4 μg/g body weight) on 10th day. ECT was supplemented orally from 8th day up to 12th day at a concentration of 5 μg/g body weight and marker parameters were evaluated after 30 days. The production of MPO and the activation of calpain were reduced 52.17% and 36.67% by ECT in lens tissue, respectively. It modulated the energy status by significantly increasing the activity of CCO 1 (55.56%) and ATP production (41.88%). ECT maintained the ionic balance in the lens by reducing the level of sodium (50%) and increasing the level of potassium (42.5%). It also reduced cell junction modifications and preserved a functional ubiquitin-proteasome pathway. The results reinforce the growing attention on wild plant food resources for preventive protection against cataract. The data suggest the value of Cassia tora leaves as a functional food for ameliorating cataract pathology.

Early light deprivation effects on human cone-driven retinal function.

PubMed

Esposito Veneruso, Paolo; Ziccardi, Lucia; Magli, Giulia; Parisi, Vincenzo; Falsini, Benedetto; Magli, Adriano

2017-03-01

To assess whether the early light deprivation induced by congenital cataract may influence the cone-driven retinal function in humans. Forty-one patients affected by congenital cataract (CC) who had undergone uncomplicated cataract extraction surgery and intraocular lens implant, and 14 healthy subjects (HS) were enrolled. All patients underwent complete ophthalmological and orthoptic evaluations and best-corrected visual acuity (BCVA) measurement; light-adapted full-field electroretinograms (ERG) and photopic negative responses (PhNR) were recorded to obtain a reliable measurement of the outer/inner retinal function and of the retinal ganglion cells' function respectively. Mean values of light-adapted ERG a- and b-wave and PhNR amplitude of CC eyes were significantly reduced and photopic ERG b-wave implicit time mean values were significantly delayed when compared to HS ones. When studying photopic ERG mean amplitudes at 5 ms, significant differences were found when comparing CC and control eyes. In CC eyes, statistically significant correlations were found between a- and b- wave amplitudes and PhNR amplitudes. No significant correlations were found between ERG parameters and BCVA, as well as between the age of CC patients at surgery and the time elapsed from lens extraction. No significant differences were found when functional parameters of bilateral and unilateral congenital cataract (uCC) eyes were compared, however uCC eyes showed significant differences when compared with contralateral healthy eyes. We found a significant impairment of cone-driven retinal responses in patients with a history of congenital cataract. These changes might result from the long-lasting effects of early light deprivation on the cone retinal pathways. Our findings support the relevance of retinal involvement in deficits induced by early light deprivation. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Unfolded-protein response–associated stabilization of p27(Cdkn1b) interferes with lens fiber cell denucleation, leading to cataract

PubMed Central

Lyu, Lei; Whitcomb, Elizabeth A.; Jiang, Shuhong; Chang, Min-Lee; Gu, Yumei; Duncan, Melinda K.; Cvekl, Ales; Wang, Wei-Lin; Limi, Saima; Reneker, Lixing W.; Shang, Fu; Du, Linfang; Taylor, Allen

2015-01-01

Failure of lens fiber cell denucleation (LFCD) is associated with congenital cataracts, but the pathobiology awaits elucidation. Recent work has suggested that mechanisms that direct the unidirectional process of LFCD are analogous to the cyclic processes associated with mitosis. We found that lens-specific mutations that elicit an unfolded-protein response (UPR) in vivo accumulate p27(Cdkn1b), show cyclin-dependent kinase (Cdk)-1 inhibition, retain their LFC nuclei, and are cataractous. Although a UPR was not detected in lenses expressing K6W-Ub, they also accumulated p27 and showed failed LFCD. Induction of a UPR in human lens epithelial cells (HLECs) also induced accumulation of p27 associated with decreased levels of S-phase kinase-associated protein (Skp)-2, a ubiquitin ligase that regulates mitosis. These cells also showed decreased lamin A/C phosphorylation and metaphase arrest. The suppression of lamin A/C phosphorylation and metaphase transition induced by the UPR was rescued by knockdown of p27. Taken together, these data indicate that accumulation of p27, whether related to the UPR or not, prevents the phosphorylation of lamin A/C and LFCD in maturing LFCs in vivo, as well as in dividing HLECs. The former leads to cataract and the latter to metaphase arrest. These results suggest that accumulation of p27 is a common mechanism underlying retention of LFC nuclei.—Lei, L., Whitcomb, E. A., Jiang, S., Chang, M.-L., Gu, Y., Duncan, M. K., Cvekl, A., Wang, W.-L., Limi, S., Reneker, L. W., Shang, F., Du, L., Taylor, A. Unfolded protein response–associated stabilization of p27(Cdkn1b) interferes with lens fiber cell denucleation, leading to cataract. PMID:26590164

Comparison of postoperative corneal changes between dry eye and non-dry eye in a murine cataract surgery model.

PubMed

Kwon, Jin Woo; Chung, Yeon Woong; Choi, Jin A; La, Tae Yoon; Jee, Dong Hyun; Cho, Yang Kyung

2016-01-01

To compare the effects of the surgical insult of cataract surgery on corneal inflammatory infiltration, neovascularization (NV) and lymphangiogenesis (LY) between the dry eye and non-dry eye in murine cataract surgery models. We established two groups of animals, one with normal eyes (non-dry eye) and the second with induced dry eyes. In both groups, we used surgical insults to mimic human cataract surgery, which consisted of lens extraction, corneal incision and suture. After harvesting of corneas on the 9(th) postoperative day and immunohistochemical staining, we compared NV, LY and CD11b+ cell infiltration in the corneas. Dry eye group had significantly more inflammatory infiltration (21.75%±7.17% vs 3.65%±1.49%; P=0.049). The dry eye group showed significantly more NV (48.21%±4.02% vs 26.24%±6.01%; P=0.016) and greater levels of LY (9.27%±0.48% vs 4.84%±1.15%; P=0.007). In corneas on which no surgery was performed, there was no induction of NV in both the dry and non-dry group, but dry eye group demonstrated more CD11b+ cells infiltration than the non-dry eye group (0.360%±0.160% vs 0.023%±0.006%; P=0.068). Dry eye group showed more NV than non-dry eye group in both topical PBS application and subconjunctival PBS injection (P=0.020 and 0.000, respectively). In a murine cataract surgery model, preexisting dry eye can induce more postoperative NV, LY, and inflammation in corneal tissue.

Comparison of postoperative corneal changes between dry eye and non-dry eye in a murine cataract surgery model

PubMed Central

Kwon, Jin Woo; Chung, Yeon Woong; Choi, Jin A; La, Tae Yoon; Jee, Dong Hyun; Cho, Yang Kyung

2016-01-01

AIM To compare the effects of the surgical insult of cataract surgery on corneal inflammatory infiltration, neovascularization (NV) and lymphangiogenesis (LY) between the dry eye and non-dry eye in murine cataract surgery models. METHODS We established two groups of animals, one with normal eyes (non-dry eye) and the second with induced dry eyes. In both groups, we used surgical insults to mimic human cataract surgery, which consisted of lens extraction, corneal incision and suture. After harvesting of corneas on the 9th postoperative day and immunohistochemical staining, we compared NV, LY and CD11b+ cell infiltration in the corneas. RESULTS Dry eye group had significantly more inflammatory infiltration (21.75%±7.17% vs 3.65%±1.49%; P=0.049). The dry eye group showed significantly more NV (48.21%±4.02% vs 26.24%±6.01%; P=0.016) and greater levels of LY (9.27%±0.48% vs 4.84%±1.15%; P=0.007). In corneas on which no surgery was performed, there was no induction of NV in both the dry and non-dry group, but dry eye group demonstrated more CD11b+ cells infiltration than the non-dry eye group (0.360%±0.160% vs 0.023%±0.006%; P=0.068). Dry eye group showed more NV than non-dry eye group in both topical PBS application and subconjunctival PBS injection (P=0.020 and 0.000, respectively). CONCLUSION In a murine cataract surgery model, preexisting dry eye can induce more postoperative NV, LY, and inflammation in corneal tissue. PMID:26949638

Effects of Short-term Preoperative Topical Ketorolac on Pupil Diameter in Eyes Undergoing Femtosecond Laser-Assisted Capsulotomy.

PubMed

Diakonis, Vasilios F; Kontadakis, Georgios A; Anagnostopoulos, Apostolos G; Yesilirmak, Nilufer; Waren, Daniel P; Cabot, Florence; Yoo, Sonia H; Donaldson, Kendall E

2017-04-01

To assess pupil diameter before and after femtosecond laser-assisted capsulotomy in patients who were pretreated with a short-term topical nonsteroidal anti-inflammatory drug (NSAID) (ketorolac) versus those without pretreatment. This prospective, randomized, observational case series included consecutive patients scheduled to undergo cataract extraction using the Catalys femtosecond laser platform (Abbott Medical Optics, Inc., Santa Ana, CA) to perform only capsulotomies. The same protocol for preoperative medical mydriasis was used for all patients, whereas pupil diameter was assessed using a surgical ruler immediately before and 3 minutes after femtosecond laser-assisted capsulotomy. The patients were divided into two groups: one received short-term topical ketorolac preoperatively and the other did not receive NSAID pretreatment (control). A total of 42 eyes of 42 patients (1 eye per patient) were included in the study. Mean pupillary miosis was 0.79 ± 1.08 and 1.57 ± 1.19 mm for the ketorolac and control groups, respectively. There was a statistically significant decrease in pupil diameter for both groups individually (P < .05). There was also a statistically significant difference between the two groups (P < .05) with the induced miosis in the eyes that did not receive topical NSAIDs prior to cataract extraction being twofold greater when compared with the miosis of the eyes that received ketorolac pretreatment. Short-term topical use of ketorolac prior to femtosecond laser-assisted cataract surgery seems to induce significantly less pupillary miosis in comparison to eyes that did not receive NSAID pretreatment. NSAID use is advised prior to femtosecond laser-assisted cataract surgery to minimize pupil miosis-related surgical difficulties or complications during cataract extraction. [J Refract Surg. 2017;33(4):230-234.]. Copyright 2017, SLACK Incorporated.

Detection of DNA Damage by Space Radiation in Human Fibroblast Cells Flown on the International Space Station

NASA Technical Reports Server (NTRS)

Wu, Honglu; Lu, Tao; Wong, Michael; Beno, Jonathan; Countryman, Stefanie; Stodieck, Louis; Karouia, Fathi; Zhang, Ye

2015-01-01

Although charged particles in space have been detected with radiation detectors on board spacecraft since the early discovery of the Van Allen Belt, reports on effects of direct exposure to space radiation in biological systems have been limited. Measurement of biological effects of space radiation has been difficult due to the low dose and low dose rate nature of the radiation environment, and the difficulty in separating the radiation effects from microgravity and other space environmental factors. In astronauts, only a small number of changes, such as increased chromosome aberrations in lymphocytes and early onset of cataracts, attributed primarily to the exposure to space radiation. In a recent experiment, human fibroblast cells were flown on the International Space Station (ISS). Cells fixed on Days 3 and 14 after reaching orbit were analyzed for phosphorylation of a histone protein H2AX by immunofluorescent staining of cells, which is a widely used marker for DNA double strand breaks. The 3-dimensional gamma-H2AX foci were captured with a laser confocal microscope. Quantitative analysis revealed a small fraction of foci that were larger and displayed a track pattern in the flight samples in comparison to the ground control. Human fibroblast cells were also exposed to low dose rate gamma rays, as well as to protons and Fe ions. Comparison of the pattern and distribution of the foci after gamma ray and charged particle exposure to our flight results confirmed that the foci found in the flown cells were indeed induced by space radiation.

Coated with nanomaterials intraocular lenses, ophthalmic and human body implantable devices with high catalytic antioxidant activities: a new nanotechnology strategy of peroxidase cellular enzyme mimics increasing the biocompatibility and therapeutic deployment of the medical prosthetic device.

PubMed

Babizhayev, Mark A

2013-04-01

While cataract surgery is generally recognized as being one of the safest operations, there is still a significant complication rate. From 30 to 50% of all patients in the United States having cataract extraction develop opacification of the posterior lens capsule within two years and require laser treatment with its own significant risk of complications. Of the patients having cataract surgery, 0.8% develop retinal detachments, from 0.6% to 1.3% were rehospitalized for corneal edema or required corneal transplantation and about 0.1% presented with endophthalmitis . Thus, aside from secondary cataract, about 2% of 1.3 million people, or 26,000 individuals in the United States annually develop serious complications as a result of cataract surgery. The aim of this investigation was to increase the safety and effectiveness of an individual intraocular lens (IOL) preventing an impairment in peroxide metabolism of the mature human cataractous lenses compared to normal lenses employing the specific nanotechnology coating which substitutes the inhibitory effect of the implantable device towards the active species of oxygen and the ability of IOL to regulate the H2O2 and lipid hydroperoxides levels in the surrounding medium. The implantation of IOLs with metabolic activity improves the capability of the surrounding ocular tissues to withstand oxidative stress induced in ocular humors by the photochemical and other metabolic reactions. The coated implantable medical device with thin film of platinum applied with magnetron sputtering, reacts as a body enzyme with deleterious peroxide compounds and free radical oxygen species in body fluids and tissue when said device is implanted into human body. The IOL having haptics coated with thin film of platinum, catalyzes the reduction of peroxide compounds to decrease their levels within the aqueous humor. Further, the coatings also scavenge toxic free radicals of oxygen, thus preventing cellular dysfunction resulting from oxidative attack. Coated IOLs according to the patented nanotechnology can address the vast majority of cataract surgery-induced complications, such as secondary cataract, intraocular inflammation (endophthalmitis) and foreign body reactions, cystoid macular oedema, corneal edema. The nanotechnology offers physicians and surgeons to develop and commercialize costeffective therapeutic medical implantable devices, products and support systems with metabolic activities for the treatment of ophthalmic diseases and of a wide range of pathological states and disorders which are treated by insertion of the implantable and prosthetic (polymeric) devices.

High- and low-LET Radiation-induced Chromosome Aberrations in Human Epithelial Cells Cultured in 3-dimensional Matrices

NASA Technical Reports Server (NTRS)

Hada, M.; George K.; Cucinotta, F. A.; Wu, H.

2008-01-01

Energetic heavy ions pose a great health risk to astronauts who participate in extended ISS missions and will be an even greater concern for future manned lunar and Mars missions. High-LET heavy ions are particularly effective in causing various biological effects, including cell inactivation, genetic mutations, cataracts and cancer induction. Most of these biological endpoints are closely related to chromosomal damage, which can be utilized as a biomarker for radiation insults. Previously, we had studied low- and high-LET radiation-induced chromosome aberrations in human epithelial cells cultured in 2-dimension (2D) using the multicolor banding fluorescence in situ hybridization (mBAND) technique. However, it has been realized that the biological response to radiation insult in a 2D in vitro cellular environment can differ significantly from the response in 3-dimension (3D) or at the actual tissue level. In this study, we cultured human epithelial cells in 3D to provide a more suitable model for human tissue. Human mammary epithelial cells (CH184B5F5/M10) were grown in Matrigel to form 3D structures, and exposed to Fe-ions at NASA Space Radiation Laboratory (NSRL) at the Brookhaven National Laboratory or 137Cs-gamma radiation source at the University of Texas MD Anderson Cancer Center. After exposure, cells were allowed to repair for 16hr before dissociation and subcultured at low density in 2D. G2 and metaphase chromosomes in the first cell cycle were collected in the first cell cycle after irradiation using a chemical-induced premature chromosome condensation (PCC) technique, and chromosome aberrations were analyzed using mBAND technique. With this technique, individually painted chromosomal bands on one chromosome allowed the identification of interchromosomal aberrations (translocation to unpainted chromosomes) and intrachromosomal aberrations (inversions and deletions within a single painted chromosome). Our data indicate a significant difference in the chromosome aberration yield between 2D and 3D cell cultures after gamma exposures, but not after Fe ion exposures. Therefore, the Relative Biological Effect (RBE) for induction of chromosome aberrations obtained in a 2D model may not accurately represent RBE values obtained for tissue exposure.

Near infrared radiation damage mechanism in the lens

NASA Astrophysics Data System (ADS)

Söderberg, Per G.; Talebizadeh, Nooshin; Galichanin, Konstantin; Kronschläger, Martin; Schulmeister, Karl; Yu, Zhaohua

2015-03-01

The current data strongly indicates that there is no photochemical effect of in vivo exposure to 1090 nm near IRR radiation within the pupil. Four groups of 20 Sprague-Dawley rats were unilaterally exposed in vivo to 96 W·cm-2 centered inside the pupil for 10, 18, 33 and 60 min, respectively depending on group belonging. This resulted in radiant exposure doses of 57, 103, 198 and 344 kJ·cm-2. Temperature evolution at the limbus during the exposure and difference of intensity of forward light scattering between the exposed and the contralateral not exposed eye was measured at 1 week after exposure. The temperature at the limbus was found to increase exponentially towards an asymptote with an asymptote temperature of around 7 °C and a time constant (1/k) of around 15 s. No increase of light scattering was found despite that the cumulated radiant exposure dose was [80;250] times the threshold for photochemically induced cataract suggested by previous empirical data. It is concluded that at 1090 nm near IRR there is no photochemical effect.

Radiation-induced eye lens changes and risk for cataract in interventional cardiology.

PubMed

Ciraj-Bjelac, O; Rehani, M; Minamoto, A; Sim, K H; Liew, H B; Vano, E

2012-01-01

Recent studies have reported a significant increase in eye lens opacities among staff in the cardiac catheterization laboratory but indicated further studies are needed to confirm the findings. To evaluate the prevalence of opacities in eyes of cardiologists, radiographers and nurses working in interventional cardiology. The eyes of 52 staff in interventional cardiology facilities and 34 age- and sex-matched unexposed controls were screened in a cardiology conference held in Kuala Lumpur by dilated slit-lamp examination, and posterior lens changes were graded. Individual cumulative lens X-ray exposures were calculated from responses to a questionnaire in terms of workload and working practice. The prevalence of posterior lens opacities among interventional cardiologists was 53%, while in nurses and radiographers it was 45%. Corresponding relative risks were 2.6 (95% CI: 1.2-5.4) and 2.2 (95% CI: 0.98-4.9), for interventional cardiologists and support staff, respectively. This study confirms a statistically significant increase in radiation-associated posterior lens changes in the eyes of interventional cardiology staff. Copyright © 2012 S. Karger AG, Basel.

Non-Invasive Health Diagnostics using Eye as a 'Window to the Body'

NASA Technical Reports Server (NTRS)

Ansari, Rafat R.

2002-01-01

As a 'window to the body', the eye offers the opportunity to use light in various forms to detect ocular and systemic abnormalities long before clinical symptoms appear and help develop preventative/therapeutic countermeasures early. The effects of space travel on human body are similar to those of normal aging. For example, radiation exposure in space could lead to formation of cataracts and cancer by damaging the DNA and causing gene mutation. Additionally, the zero-gravity environment causes fluid shifts in the upper extremities of the body and changes the way blood flows and organ system performs. Here on Earth, cataract, age-related macular degeneration (AMD), diabetic retinopathy (DR), and glaucoma are major eye diseases and are expected to double in next two decades. To detect, prevent, and treat untoward effects of prolonged space travel in real-time requires the development of non-invasive diagnostic technologies that are compact and powerful. We are developing fiber-optic sensors to evaluate the ocular tissues in health, aging, and disease employing the techniques of dynamic light scattering (cataract, uveitis, Alzheimer's, glaucoma, DR, radiation damage, refractive surgery outcomes), auto-fluorescence (aging, DR), laser-Doppler flowmetry (choroidal blood flow), Raman spectroscopy (AMD), polarimetry (diabetes), and retinal oximetry (occult blood loss). The non-invasive feature of these technologies integrated in a head-mounted/goggles-like device permits frequent repetition of tests, enabling evaluation of the results to therapy that may ultimately be useful in various telemedicine applications on Earth and in space.

Radiofrequency/Microwave Radiation Biological Effects and Safety Standards: A Review

DTIC Science & Technology

1994-06-01

reported that a 50 year old woman had developed cataracts after intermittent exposure to a 2.45 GHz microwave oven. The incident power density levels were...include: Survelance, Communications, Command and Control, Intelligence, Signal Processing, Computer Sience and Technology, Electrom Technology, Photoracs and laiity Saences. S* I l I

Detection of DNA Damage by Space Radiation in Human Fibroblasts Flown on the International Space Station

NASA Technical Reports Server (NTRS)

Lu, Tao; Zhang, Ye; Wong, Michael; Feiveson, Alan; Gaza, Ramona; Stoffle, Nicholas; Wang, Huichen; Wilson, Bobby; Rohde, Larry; Stodieck, Louis;

Detection of DNA damage by space radiation in human fibroblasts flown on the International Space Station.

PubMed

Lu, Tao; Zhang, Ye; Wong, Michael; Feiveson, Alan; Gaza, Ramona; Stoffle, Nicholas; Wang, Huichen; Wilson, Bobby; Rohde, Larry; Stodieck, Louis; Karouia, Fathi; Wu, Honglu

2017-02-01

Although charged particles in space have been detected with radiation detectors on board spacecraft since the discovery of the Van Allen Belts, reports on the effects of direct exposure to space radiation in biological systems have been limited. Measurement of biological effects of space radiation is challenging due to the low dose and low dose rate nature of the radiation environment, and due to the difficulty in distinguishing the radiation effects from microgravity and other space environmental factors. In astronauts, only a few changes, such as increased chromosome aberrations in their lymphocytes and early onset of cataracts, are attributed primarily to their exposure to space radiation. In this study, cultured human fibroblasts were flown on the International Space Station (ISS). Cells were kept at 37°C in space for 14 days before being fixed for analysis of DNA damage with the γ-H2AX assay. The 3-dimensional γ-H2AX foci were captured with a laser confocal microscope. Quantitative analysis revealed several foci that were larger and displayed a track pattern only in the Day 14 flight samples. To confirm that the foci data from the flight study was actually induced from space radiation exposure, cultured human fibroblasts were exposed to low dose rate γ rays at 37°C. Cells exposed to chronic γ rays showed similar foci size distribution in comparison to the non-exposed controls. The cells were also exposed to low- and high-LET protons, and high-LET Fe ions on the ground. Our results suggest that in G1 human fibroblasts under the normal culture condition, only a small fraction of large size foci can be attributed to high-LET radiation in space. Published by Elsevier Ltd.

Detection of DNA damage by space radiation in human fibroblasts flown on the International Space Station

NASA Astrophysics Data System (ADS)

Lu, Tao; Zhang, Ye; Wong, Michael; Feiveson, Alan; Gaza, Ramona; Stoffle, Nicholas; Wang, Huichen; Wilson, Bobby; Rohde, Larry; Stodieck, Louis; Karouia, Fathi; Wu, Honglu

2017-02-01

Although charged particles in space have been detected with radiation detectors on board spacecraft since the discovery of the Van Allen Belts, reports on the effects of direct exposure to space radiation in biological systems have been limited. Measurement of biological effects of space radiation is challenging due to the low dose and low dose rate nature of the radiation environment, and due to the difficulty in distinguishing the radiation effects from microgravity and other space environmental factors. In astronauts, only a few changes, such as increased chromosome aberrations in their lymphocytes and early onset of cataracts, are attributed primarily to their exposure to space radiation. In this study, cultured human fibroblasts were flown on the International Space Station (ISS). Cells were kept at 37 °C in space for 14 days before being fixed for analysis of DNA damage with the γ-H2AX assay. The 3-dimensional γ-H2AX foci were captured with a laser confocal microscope. Quantitative analysis revealed several foci that were larger and displayed a track pattern only in the Day 14 flight samples. To confirm that the foci data from the flight study was actually induced from space radiation exposure, cultured human fibroblasts were exposed to low dose rate γ rays at 37 °C. Cells exposed to chronic γ rays showed similar foci size distribution in comparison to the non-exposed controls. The cells were also exposed to low- and high-LET protons, and high-LET Fe ions on the ground. Our results suggest that in G1 human fibroblasts under the normal culture condition, only a small fraction of large size foci can be attributed to high-LET radiation in space.

Alterations in the lenticular protein profile in experimental selenite-induced cataractogenesis and prevention by ellagic acid.

PubMed

Sakthivel, Muniyan; Geraldine, Pitchairaj; Thomas, Philip A

2011-08-01

Accumulating evidence suggests that oxidative stress underlies age-related formation of cataract, and that antioxidants retard cataractogenesis. This study aimed to evaluate whether ellagic acid, a natural polyphenol with antioxidant properties, prevents alterations in the lenticular protein profile in an experimental model of selenite cataract. Alterations in lenticular protein were determined by two-dimensional electrophoresis (2DE) and image analysis. Eluted αA-crystallin spots were analyzed by mass spectrometry. Western blot analysis was also performed to confirm the differential expression of certain crystallins and cytoskeletal proteins. In cataractous lenses, 2DE and image analysis revealed approximately 45 and 60 prominent spots in soluble and insoluble protein fractions respectively. Analysis of the pI and molecular weight of protein spots revealed differences in the expression of crystallin proteins in soluble and insoluble fractions. Western blot analysis confirmed changes in the expression of αA- and βB1- crystallins in both soluble and insoluble protein fractions, while mass spectrometry confirmed the degradation of αA-crystallin in selenite cataractous lenses. Western blot analysis also confirmed the occurrence of altered expression of certain cytoskeletal proteins in insoluble fractions. However, the lenticular protein profile in lenses from selenite-challenged, ellagic acid-treated rats was essentially similar to that noted in lenses from normal rats. The present study confirms the importance of structural and cytoskeletal proteins in the maintenance of lenticular transparency; the results also suggest that ellagic acid prevents lenticular protein alterations induced by selenite in an experimental setting.

Identification of long non-coding RNA and mRNA expression in βΒ2-crystallin knockout mice.

PubMed

Jia, Yin; Xiong, Kang; Ren, Han-Xiao; Li, Wen-Jie

2018-05-01

βΒ2-crystallin (CRYBB2) is expressed at an increased level in the postnatal lens cortex and is associated with cataracts. Improved understanding of the underlying biology of cataracts is likely to be critical for the development of early detection strategies and new therapeutics. The present study aimed to identify long non-coding RNAs (lncRNAs) and mRNAs associated with CRYBB2 knockdown (KO)-induced cataracts. RNAs from 3 non-treated mice and 3 CRYBB2 KO mice were analyzed using the Affymetrix GeneChip Mouse Gene 2.0 ST array. A total of 149 lncRNAs and 803 mRNAs were identified to have upregulated expression, including Snora73b, Klk1b22 and Rnu3a, while the expression levels of 180 lncRNAs and 732 mRNAs were downregulated in CRYBB2 KO mice, including Snord82, Snhg9 and Foxn3. This lncRNA and mRNA expression profile of mice with CRYBB2 KO provides a basis for studying the genetic mechanisms of cataract progression.

Wavefront shaping to correct intraocular scattering

NASA Astrophysics Data System (ADS)

Artal, Pablo; Arias, Augusto; Fernández, Enrique

2018-02-01

Cataracts is a common ocular pathology that increases the amount of intraocular scattering. It degrades the quality of vision by both blur and contrast reduction of the retinal images. In this work, we propose a non-invasive method, based on wavefront shaping (WS), to minimize cataract effects. For the experimental demonstration of the method, a liquid crystal on silicon (LCoS) spatial light modulator was used for both reproduction and reduction of the realistic cataracts effects. The LCoS area was separated in two halves conjugated with the eye's pupil by a telescope with unitary magnification. Thus, while the phase maps that induced programmable amounts of intraocular scattering (related to cataract severity) were displayed in a one half of the LCoS, sequentially testing wavefronts were displayed in the second one. Results of the imaging improvements were visually evaluated by subjects with no known ocular pathology seeing through the instrument. The diffracted intensity of exit pupil is analyzed for the feedback of the implemented algorithms in search for the optimum wavefront. Numerical and experimental results of the imaging improvements are presented and discussed.

Postoperative corneal shape changes: microincision versus small-incision coaxial cataract surgery.

PubMed

Hayashi, Ken; Yoshida, Motoaki; Hayashi, Hideyuki

2009-02-01

To compare changes in corneal topography and in regular and irregular astigmatism after coaxial clear corneal microincision cataract surgery (MICS) and after coaxial small-incision cataract surgery (SICS). Hayashi Eye Hospital, Fukuoka, Japan. Induced corneal astigmatism was determined using vector analysis. The averaged corneal shape changes and degree of irregular astigmatism were examined using videokeratography preoperatively as well as 2 days and 1, 2, 4, and 8 weeks postoperatively. One hundred twenty eyes of 60 patients scheduled for phacoemulsification were evaluated. Sixty eyes had MICS (2.00 mm), and the 60 contralateral eyes had SICS (2.65 mm). The mean induced corneal astigmatism was significantly less in the MICS group than in the SICS group (P

A study of lens opacification for a Mars mission

NASA Technical Reports Server (NTRS)

Shinn, J. L.; Wilson, J. W.; Cox, A. B.; Lett, J. T.

1991-01-01

A method based on risk-related cross sections is used to estimate risks of 'stationary' cataracts caused by radiation exposures during extended missions in deep space. Estimates of the even more important risk of late degenerative cataractogenesis are made on the basis of the limited data available. Data on lenticular opacification in the New Zealand white rabbit, an animal model from which such results can be extrapolated to humans, are analyzed by the Langley cosmic ray shielding code (HZETRN) to generate estimates of stationary cataract formation resulting from a Mars mission. The effects of the composition of shielding material and the relationship between risk and LET are given, and the effects of target fragmentation on the risk coefficients are evaluated explicitly.

A fiber optic sensor for ophthalmic refractive diagnostics

NASA Technical Reports Server (NTRS)

Ansari, Rafat R.; Dhadwal, Harbans S.; Campbell, Melanie C. W.; Dellavecchia, Michael A.

1992-01-01

This paper demonstrates the application of a lensless fiber optic spectrometer (sensor) to study the onset of cataracts. This new miniaturized and rugged fiber optic probe is based upon dynamic light scattering (DLS) principles. It has no moving parts, no apertures, and requires no optical alignment. It is flexible and easy to use. Results are presented for cold-induced cataract in excised bovine eye lenses, and aging effects in excised human eye lenses. The device can be easily incorporated into a slit-lamp apparatus (ophthalmoscope) for complete eye diagnostics.

The location of incision in cataract surgery and its impact on induced astigmatism.

PubMed

Hashemi, Hassan; Khabazkhoob, Mehdi; Soroush, Sara; Shariati, Reyhane; Miraftab, Mohammad; Yekta, Abbasali

2016-01-01

The purpose of the present study is a systematic review of previous studies on choosing the best incision site for the correction of astigmatism in cataract surgery and assessing the amount of surgically induced astigmatism (SIA) with each approach. Regardless of astigmatism axis, studies show that using an on-axis incision is associated with favorable results for 0.5-1.0 diopter (D) of astigmatism. In cases with more than 1.0 D astigmatism, paired on-axis incisions can be appreciably efficient in astigmatism correction and cause at least 1.5 D SIA. Considering the amount of SIA, a temporal incision is the best approach when the patient has minimal amounts of corneal astigmatism preoperatively. At higher levels of astigmatism, if no other astigmatism correction method is used simultaneously, the temporal incision is used less frequently; however, since it is associated with the least SIA, it is still the choice site when another correction method is used. The temporal incisions in cataract surgery are associated with little SIA and are appropriate choices for mild preoperative astigmatism. At higher levels of preoperative astigmatism, superior incisions are associated with better results when combined methods are not applied.

Comparison of surgically induced astigmatism in various incisions in manual small incision cataract surgery.

PubMed

Jauhari, Nidhi; Chopra, Deepak; Chaurasia, Rajan Kumar; Agarwal, Ashutosh

2014-01-01

To determine the surgically induced astigmatism (SIA) in Straight, Frown and Inverted V shape (Chevron) incisions in manual small incision cataract surgery (SICS). A prospective cross sectional study was done on a total of 75 patients aged 40y and above with senile cataract. The patients were randomly divided into three groups (25 each). Each group received a particular type of incision (Straight, Frown or Inverted V shape incisions). Manual SICS with intraocular lens (IOL) implantation was performed. The patients were compared 4wk post operatively for uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA) and SIA. All calculations were performed using the SIA calculator version 2.1, a free software program. The study was analyzed using SPSS version 15.0 statistical analysis software. The study found that 89.5% of patients in Straight incision group, 94.2% in Frown incision group and 95.7% in Inverted V group attained BCVA post-operatively in the range of 6/6 to 6/18. Mean SIA was minimum (-0.88±0.61D×90 degrees) with Inverted V incision which was statistically significant. Inverted V (Chevron) incision gives minimal SIA.

Evaluation of the Combined Effects of Gamma Radiation and High Dietary Iron on Peripheral Leukocyte Distribution and Function

NASA Technical Reports Server (NTRS)

Crucian, Brian E.; Morgan, Jennifer L. L.; Quiriarte, Heather A.; Sams, Clarence F.; Smith, Scott M.; Zwart, Sara R.

2011-01-01

NASA is concerned with the health risks to astronauts, particularly those risks related to radiation exposure. Both radiation and increased iron stores can independently increase oxidative damage, resulting in protein, lipid and DNA oxidation. Oxidative stress increases the risk of many health problems including cancer, cataracts, and heart disease. This study, a subset of a larger interdisciplinary investigation of the combined effect of iron overload on sensitivity to radiation injury, monitored immune parameters in the peripheral blood of rats subjected to gamma radiation, high dietary iron or both. Specific immune measures consisted of (A) peripheral leukocyte distribution; (B) plasma cytokine levels; (C) cytokine production profiles following whole blood stimulation of either T cells or monocytes.

Altered DNA Methylation and Expression Profiles of 8-Oxoguanine DNA Glycosylase 1 in Lens Tissue from Age-related Cataract Patients.

PubMed

Wang, Yong; Li, Fei; Zhang, Guowei; Kang, Lihua; Qin, Bai; Guan, Huaijin

2015-01-01

Oxidative stress and DNA damage contribute to the pathogenesis of age-related cataract (ARC). Most oxidative DNA lesions are repaired via the base excision repair (BER) proteins including 8-oxoguanine DNA glycosylase 1 (OGG1). This study examined DNA methylation of CpG islands upstream of OGG1 and their relation to the gene expression in lens cortex from ARC patients. The clinical case-control study consisted of 15 cortical type of ARC patients and 15 age-matched non-ARC controls who received transparent lens extraction due to vitreoretinal diseases. OGG1 expression in lens cortex was analyzed by qRT-PCR and Western blot. The localization and the proportion of cells positive for OGG1 were determined by immunofluorescence. Bisulfite-sequencing PCR (BSP) was performed to evaluate the methylation status of CpG islands near OGG1 in DNA extracted from lens cortex. To test relationship between the methylation and the expression of the gene of interest, 5-Aza-2'-deoxycytidine (5-Aza-dC) was used to induce demethylation of cultured human lens epithelium B-3 (HLE B-3). To test the role of OGG1 in the repair of cellular damage, HLE B-3 was transfected with OGG1 vector, followed by ultraviolet radiation b (UVB) exposure to induce apoptosis. The mRNA and protein levels of OGG1 were significantly reduced in the lens cortex of ARC. Immunofluorescence showed that the proportion of OGG1-positive cells decreased significantly in ARC cortex in comparison with the control. The CpG island in first exon of OGG1 displayed hypermethylation in the DNA extracted from the lens cortex of ARC. Treatment of HLEB-3 cells with 5-Aza-dC upregulated OGG1 expression. UVB-induced apoptosis was attenuated after transfection with OGG1. A reduced OGG1 expression was correlated with hypermethylation of a CpG island of OGG1 in lens cortex of ARC. The role of epigenetic change in OGG1 gene in the susceptibility to oxidative stress induced cortical ARC is warranted to further study.

Long-term follow-up of the genital organs and eye lenses in three cases of acute radiation sickness from a 60Co radiation accident in China.

PubMed

Xing, Zhi Wei; Jiang, En Hai; Du, Jian Ying; Zhao, Feng Ling; Fu, Bao Hua; Jiang, Li Ping; Wang, Xiao Guang; Zhao, Xin Ran; Liu, Qiang; Jiang, Bo

2015-01-01

A follow-up study aimed primarily at investigating late radiation effects on the genital organs and eye lenses was performed between 1999 and 2010 on three individuals who suffered from acute radiation sickness in China. The examination included a medical history, a physical examination, ultrasonography, laboratory analysis, and an ophthalmologic examination. In Case 1, amenorrhea occurred after exposure to a Co source. The uterus and ovaries were significantly narrowed in the second year following exposure. The estradiol level decreased significantly during the first 3 y; progesterone was lowest in the second year; and levels of follicle-stimulating hormone and luteinizing hormone increased, especially in the first year. The lenses in both eyes appeared opaque 6 mo after the exposure, resulting in a gradual deterioration in visual acuity. In Case 2 (8 y old), the levels of testosterone and estradiol were normal. In Case 3, the levels of testosterone and estradiol were also normal, but the sperm count was 0 from 6 mo to 1 y, and the proportion of abnormal sperm was increased from 3-5 y after the accident. The lenses in Case 3 also began to turn opaque in the ninth year after the accident. In Case 1, the ovarian function was reduced, leading to amenorrhea and early menopause. In Case 3, the sperm count was reduced and the number of abnormal sperm was increased due to testicular damage by radiation. Radiation-induced cataracts occurred in both Case 1 and Case 3.

The Origin of Cataracts in the Lens from Infrared Laser Radiation.

DTIC Science & Technology

1980-08-31

melanin, absorbs only very slightly at wavelengths greater than 1000 am (Hayes and Wolbarsht 1968; Blois , 1969) as shown in Figure 2, the total IX...program, especially B. S. Yamanashi, M. A. Orr, I. B. C. Matheson, J. S. Zigler and R. Antonucci. REFERENCES 1. Blois , M. S., Jr. Biological free

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harada, Ken, E-mail: keharada@ncc.go.jp; Murakami, Naoya; Kitaguchi, Mayuka

Purpose: To evaluate the natural history, behavior of progression, prognostic factors, and treatment-related adverse effects of primary ocular adnexal mucosa-associated lymphoid tissue (MALT) lymphoma (POAML). Methods and Materials: Eighty-six patients with histologically proven stage I POAML treated with radiation therapy at National Cancer Center Hospital, Tokyo between 1990 and 2010 were retrospectively reviewed. The median age was 56 years (range, 18-85 years). The median dose administered was 30 Gy (range, 30-46 Gy). Seventy-seven patients (90%) were treated by radiation therapy alone. Results: The median follow-up duration was 9 years (range, 0.9-22 years). The 5- and 10-year overall survival (OS) rates were 97.6% and 93.5%, respectively, andmore » no patients died of lymphoma. Patients with tumor sizes ≥4 cm showed a greater risk of contralateral relapse (P=.012). Six patients with contralateral relapse were seen and treated by radiation therapy alone, and all the lesions were controlled well, with follow-up times of 3 to 12 years. There was 1 case of local relapse after radiation therapy alone, and 3 cases of relapse occurred in a distant site. Cataracts developed in 36 of the 65 eyes treated without lens shielding and in 12 of the 39 patients with lens shielding (P=.037). Conclusions: The majority of patients with POAML showed behavior consistent with that of localized, indolent diseases. Thirty gray of local irradiation seems to be quite effective. The initial bilateral involvement and contralateral orbital relapses can be also controlled with radiation therapy alone. Lens shielding reduces the risk of cataract.« less

Short-term outcomes of small incision cataract surgery provided by a regional population in the Pacific.

PubMed

Bhikoo, Riyaz; Vellara, Hans; Lolokabaira, Salome; Murray, Neil; Sikivou, Biu; McGhee, Charles

2017-11-01

This study aims to describe patient demographics, visual and surgical outcomes of a cohort undergoing small incision cataract surgery at a Pacific regional ophthalmic training facility. This is a prospective, longitudinal study conducted at the Pacific Eye Institute, Fiji. One hundred fifty-six patients underwent small incision cataract surgery. Preoperatively, a complete ophthalmic examination, including pachymetry and macular optical coherence tomography performed by two independent investigators. Temporal small incision cataract surgery with intraocular lens insertion was performed by ophthalmologists, and trainee ophthalmologists. Follow-up occurred at day one, four weeks and 3 months. Patient characteristics, visual outcomes including surgically induced astigmatism and complications. Ninety-one per cent (142/156) attended 3-month follow-up with median age 63 years (range 19-82), 52% female (81/156) and 58% (90/156) Fijian ethnicity. In 37% (57/156), the contralateral eye was pseudophakic. Mean preoperative best spectacle-corrected visual acuity was logMAR 1.44 (6/165). At 3 months, 74% (105/142) achieved ≥6/18 unaided vision (94% [133/142] best spectacle-corrected visual acuity). Mean postoperative spherical equivalent was -0.78 (SD 0.95) D and mean surgically induced astigmatism 1.04 (0.57) D. Complications included posterior capsular rupture with vitreous loss (4% [6/156]), optical coherence tomography confirmed macular oedema (8% [12/152] at 4 weeks), significant posterior capsular opacity (23% [31/136]) and >5% increase in preoperative pachymetry (1% [1/142]) at 3 months. Reduction in preoperative best spectacle-corrected visual acuity occurred in 2% (3/142). No cases of endophthalmitis. Small incision cataract surgery provided to a regional population is effective with 94% achieving the World Health Organisation's definition of 'Good Vision' (≥6/18). Refinements in biometric and surgical techniques may allow a greater proportion of patients to achieve good unaided vision. © 2017 Royal Australian and New Zealand College of Ophthalmologists.

M-BAND Analysis of Chromosome Aberration Induced by Fe-Ions in Human Epithelial Cells Cultured in 3-Dimensional Matrices

NASA Technical Reports Server (NTRS)

Hada, M.; Cucinotta, F. A.; Wu, H.

2008-01-01

Energetic heavy ions pose a great health risk to astronauts in extended ISS and future lunar and Mars missions. High-LET heavy ions are particularly effective in causing various biological effects, including cell inactivation, genetic mutations, cataracts and cancer induction. Most of these biological endpoints are closely related to chromosomal damage, which can be utilized as a biomarker for radiation insults. Previously, we had studied low- and high-LET radiation-induced chromosome aberrations in human epithelial cells cultured in 2-dimension (2D) using the multicolor banding fluorescence in situ hybridization (mBAND) technique. However, it has been realized that the biological response to radiation insult in a 2D cellular environment in vitro can differ significantly from the response in 3-dimension (3D) or at the actual tissue level. In this study, we cultured human epithelial cells in 3D to provide a more suitable model for human tissue. Human mammary epithelia cells (CH184B5F5/M10) were grown in Matrigel to form 3D structures, and exposed to Fe-ions at NASA Space Radiation Laboratory (NSRL) at the Brookhaven National Laboratory or 137Cs-gamma radiation source at the University of Texas MD Anderson Cancer Center. After exposure, cells were allowed to repair for 16hr before dissociation and subcultued at low density in 2D. G2 and metaphase chromosomes in the first cell cycle were collected using a chemical-induced premature chromosome condensation (PCC) technique, and chromosome aberrations were analyzed using mBAND technique. With this technique, individually painted chromosomal bands on one chromosome allowed the identification of interchromosomal aberrations (translocation to unpainted chromosomes) and intrachromosomal aberrations (inversions and deletions within a single painted chromosome). Our data indicate a significant difference of the chromosome aberration yield between 2D and 3D cell cultures for gamma exposures, but not for Fe ion exposures. Therefore, the RBE for chromosome aberrations obtained in a 2D model may not represent accurately the RBE for tissues.

Alzheimer's and Danish dementia peptides induce cataract and perturb retinal architecture in rats.

PubMed

Reddy, G Bhanuprakash; Reddy, P Yadagiri; Surolia, Avadhesha

2017-03-01

Familial Danish dementias (FDDs) are autosomal dominant neurodegenerative disorders that are associated with visual defects. In some aspects, FDD is similar to Alzheimer's disease (AD)- the amyloid deposits in FDD and AD are made of short peptides: amyloid β (Aβ) in AD and ADan in FDD. Previously, we demonstrated an interaction between the dementia peptides and α-crystallin leading to lens opacification in organ culture due to impaired chaperone activity of α-crystallin. Herein, we report the in vivo effects of ADan and Aβ on the eye. ADan [reduced (ADan-red) and oxidized (ADan-oxi)] and Aβ (Aβ1-40 and Aβ1-42) were injected intravitreally in rats. The onset of cataract was seen after injection of all the peptides, but the cataract matured by 2 weeks in the case of ADan-red, 5 weeks for ADan-oxi and 6 weeks for Aβ1-40, while Aβ1-42 had minimal effect on cataract progression. The severity of cataract is associated with insolubilization and alterations in crystallins and loss of chaperone activity of α-crystallin. Further, disruption of the architecture of the retina was evident from a loss of rhodopsin, increased gliosis, and the thinning of the retina. These results provide a basis for the dominant heredo-otoophthalmo-encephalopathy (HOOE)/FDD syndrome and indicate that ADan peptides are more potent than Aβpeptides in inflicting visual impairment.

Early detection of cataract and response to pantethine therapy with non-invasive static and dynamic light scattering

NASA Astrophysics Data System (ADS)

Ansari, Rafat R.; King, James F.; Seeberger, Teri; Clark, John I.

2003-07-01

Cataractogenesis is a risk factor for space travelers. Here on earth, half of all blindness is due to cataracts. At this time, the only known treatment is surgical removal of the lens. In this paper, we present static and dynamic light scattering (DLS) measurements of early onset of cataract before it has any effect on vision and to test the effectiveness of pantethine as an anticataract agent in reversing cataracts. In this preliminary study, experiments were conducted on 12 rodents. Static measurements were performed by scanning the animal eye (cornea to retina) at a laser power of 80 microwatts to collect photons or scattered intensity in steps of 10 microns. The rodents studied were control, selenite injected, and selenite plus pantethine injected. Selenite was used to induce cataracts. Static and dynamic changes (increase in light scatter and crystalline size) in the lenses are quantitatively measured as early as 1 day post selenite injections. Scattering intensity and DLS measurements from lenses of animals administered pantethine resembled controls. These subtle molecular changes are not noticeable when the animals are examined with conventional ophthalmic instruments because their lenses remain transparent. Acknowledgements: Technical support from C.Ganders, University of Washington, Seattle, NEI research grant EY04542 (JIC) and support under a NASA-NEI/NIH interagency agreement (RRA) are greatly appreciated. JFK works for QSS Inc. at NASA GRC.

Reliability of automatic biometric iris recognition after phacoemulsification or drug-induced pupil dilation.

PubMed

Seyeddain, Orang; Kraker, Hannes; Redlberger, Andreas; Dexl, Alois K; Grabner, Günther; Emesz, Martin

2014-01-01

To investigate the reliability of a biometric iris recognition system for personal authentication after cataract surgery or iatrogenic pupil dilation. This was a prospective, nonrandomized, single-center, cohort study for evaluating the performance of an iris recognition system 2-24 hours after phacoemulsification and intraocular lens implantation (group 1) and before and after iatrogenic pupil dilation (group 2). Of the 173 eyes that could be enrolled before cataract surgery, 164 (94.8%) were easily recognized postoperatively, whereas in 9 (5.2%) this was not possible. However, these 9 eyes could be reenrolled and afterwards recognized successfully. In group 2, of a total of 184 eyes that were enrolled in miosis, a total of 22 (11.9%) could not be recognized in mydriasis and therefore needed reenrollment. No single case of false-positive acceptance occurred in either group. The results of this trial indicate that standard cataract surgery seems not to be a limiting factor for iris recognition in the large majority of cases. Some patients (5.2% in this study) might need "reenrollment" after cataract surgery. Iris recognition was primarily successful in eyes with medically dilated pupils in nearly 9 out of 10 eyes. No single case of false-positive acceptance occurred in either group in this trial. It seems therefore that iris recognition is a valid biometric method in the majority of cases after cataract surgery or after pupil dilation.

Evidence Report: Risk of Cardiovascular Disease and Other Degenerative Tissue Effects from Radiation Exposure

NASA Technical Reports Server (NTRS)

Patel, Zarana; Huff, Janice; Saha, Janapriya; Wang, Minli; Blattnig, Steve; Wu, Honglu; Cucinotta, Francis

2015-01-01

Occupational radiation exposure from the space environment may result in non-cancer or non-CNS degenerative tissue diseases, such as cardiovascular disease, cataracts, and respiratory or digestive diseases. However, the magnitude of influence and mechanisms of action of radiation leading to these diseases are not well characterized. Radiation and synergistic effects of radiation cause DNA damage, persistent oxidative stress, chronic inflammation, and accelerated tissue aging and degeneration, which may lead to acute or chronic disease of susceptible organ tissues. In particular, cardiovascular pathologies such as atherosclerosis are of major concern following gamma-ray exposure. This provides evidence for possible degenerative tissue effects following exposures to ionizing radiation in the form of the GCR or SPEs expected during long-duration spaceflight. However, the existence of low dose thresholds and dose-rate and radiation quality effects, as well as mechanisms and major risk pathways, are not well-characterized. Degenerative disease risks are difficult to assess because multiple factors, including radiation, are believed to play a role in the etiology of the diseases. As additional evidence is pointing to lower, space-relevant thresholds for these degenerative effects, particularly for cardiovascular disease, additional research with cell and animal studies is required to quantify the magnitude of this risk, understand mechanisms, and determine if additional protection strategies are required.The NASA PEL (Permissive Exposure Limit)s for cataract and cardiovascular risks are based on existing human epidemiology data. Although animal and clinical astronaut data show a significant increase in cataracts following exposure and a reassessment of atomic bomb (A-bomb) data suggests an increase in cardiovascular disease from radiation exposure, additional research is required to fully understand and quantify these adverse outcomes at lower doses (less than 0.5 gray (SI unit for ionizing radiation dosage, i.e. one joule of radiation energy per one kilogram of matter)) to facilitate risk prediction. This risk has considerable uncertainty associated with it, and no acceptable model for projecting degenerative tissue risk is currently available. In particular, risk factors such as obesity, alcohol, and tobacco use can act as confounding factors that contribute to the large uncertainties. The PELs could be violated under certain scenarios, including following a large SPE (solar proton event) or long-term GCR (galactic cosmic ray) exposure. Specifically, for a Mars mission, the accumulated dose is sufficiently high that epidemiology data and preliminary risk estimates suggest a significant risk for cardiovascular disease. Ongoing research in this area is intended to provide the evidence base for accurate risk quantification to determine criticality for extended duration missions. Data specific to the space radiation environment must be compiled to quantify the magnitude of this risk to decrease the uncertainty in current PELs and to determine if additional protection strategies are required. New research results could lead to estimates of cumulative radiation risk from CNS and degenerative tissue diseases that, when combined with the cancer risk, may have major negative impacts on mission design, costs, schedule, and crew selection. The current report amends an earlier report (Human Research Program Requirements Document, HRP-47052, Rev. C, dated Jan 2009) in order to provide an update of evidence since 2009.

Cataractogenesis from high-LET radiation and the Casarett model

NASA Astrophysics Data System (ADS)

Cox, A. B.; Lee, A. C.; Lett, J. T.; Ainsworth, E. J.; Jose, J. G.

Space radiations, especially heavy ions, constitute significant hazards to astronauts. These hazards will increase as space missions lengthen. Moreover, the dangers to astronauts will be enhanced by the persistence, or even the progression, of biological damage throughout their subsequent life spans. To assist in the assessment of risks to astronauts, we are investigating the long-term effects of heavy ions on specific animal tissues. In one study, the eyes of rabbits of various ages were exposed to a single dose of Bragg plateau 20Ne ions (LET∞ ≅ 30 keV/μm). The development of cataracts has shown a pronounced age-related response during the first year after irradiation, and will be followed for two more years. In other studies, mice were exposed to single or fractionated doses of 12C ions (4-cm spread-out Bragg peak; dose-averaged LET∞ = 70-80 keV/μm) or 60Co γ-photons (LET∞ = 0.3 keV/μm). Measurements of the frequency of posterior lens opacification have shown that the tissue sparing observed with dose fractionation of γ-photons was absent when 12C-ion doses were fractionated. Development of posterior lens cataracts was also followed for long periods (up to 21 months) in mice exposed to single doses of Bragg plateau HZE particles (40Ar, 20Ne and 12C ions: LET∞ ≅ 100, 30 and 10 keV/μm, respectively) or 225 kVp X-rays. Based on average cataract levels at the different observation times, the RBE's (RBE = relative biological effectiveness) for the ions were circa 5, 3 and 1-2, respectively, over the range of doses used (0.05-0.9 Gy). Investigations of cataractogenesis are useful for exploring the model of radiation damage proposed by Casarett [1] and by Rubin and Casarett [2] with a tissue not connected directly to the vasculature.

Light Modulates Ocular Complications in an Albino Rat Model of Type 1 Diabetes Mellitus.

PubMed

Andrawus, Elias; Veildbaum, Gizi; Zemel, Esther; Leibu, Rina; Perlman, Ido; Shehadeh, Naim

2017-07-01

The purpose of the study was to assess potential interactions of light exposure and hyperglycemia upon ocular complications in diabetic rats. Streptozotocin-induced (STZ-induced) diabetic rats ( N = 39) and non-diabetic rats ( N = 9) were distributed into eight groups according to the irradiance and color of the light phase during the 12/12-hour light/dark regime. Follow-up lasted 90 days and included assessment of cataract development and electroretinogram (ERG) recordings. Stress to the retina was also assessed by glial fibrillary acidic protein immunocytochemistry. Cataract development was fast in diabetic rats that were exposed to unattenuated white light or to bright colored lights during the light phase. Diabetic rats that were kept under attenuated brown or yellow light during the light phase exhibited slower rate of cataract development. Electroretinogram responses indicated very severe retinal damage in diabetic rats kept under bright colored lights in the blue-yellow range or bright white light during the light phase. Electroretinogram damage was milder in rats kept under bright red light or attenuated yellow or brown light during the light phase. Glial fibrillary acidic protein expression in retinal Müller cells was consistent with ERG assessment of retinal damage. Attenuating white light and filtering out short wavelengths have a protective effect on the eyes of diabetic rats as evident by slower rate of cataract formation and a smaller degree of retinal damage. Our findings suggest that special glasses attenuating light exposure and filtering out short wavelengths (400-530 nm) may be beneficial for diabetic patients.

Protective effect of Pterocarpus marsupium bark extracts against cataract through the inhibition of aldose reductase activity in streptozotocin-induced diabetic male albino rats.

PubMed

Xu, YanLi; Zhao, Yongxia; Sui, YaNan; Lei, XiaoJun

2018-04-01

The present study was aimed to investigate the protective effect of Pterocarpus marsupium bark extracts against cataract in streptozotocin-induced diabetic male albino rats. Aldose reductase is a key enzyme in the intracellular polyol pathway, which plays a major role in the development of diabetic cataract. Rats were divided into five groups as normal control, diabetic control, and diabetic control treated with different concentrations of Pterocarpus marsupium bark extracts. Presence of major constituents in Pterocarpus marsupium bark extract was performed by qualitative analysis. Body weight changes, blood glucose, blood insulin, and reduced glutathione (GSH) and aldose reductase mRNA and protein expression were determined. Rat body weight gain was noted following treatment with bark extracts. The blood glucose was reduced up to 36% following treatment with bark extracts. The blood insulin and tissue GSH contents were substantially increased more than 100% in diabetic rats following treatment with extracts. Aldose reductase activity was reduced up to 79.3% in diabetic rats following treatment with extracts. V max , K m , and K i of aldose reductase were reduced in the lens tissue homogenate compared to the diabetic control. Aldose reductase mRNA and protein expression were reduced more than 50% following treatment with extracts. Treatment with Pterocarpus marsupium bark was able to normalize these levels. Taking all these data together, it is concluded that the use of Pterocarpus marsupium bark extracts could be the potential therapeutic approach for the reduction of aldose reductase against diabetic cataract.

Reduction of oxidative-nitrosative stress underlies anticataract effect of topically applied tocotrienol in streptozotocin-induced diabetic rats

PubMed Central

Abdul Nasir, Nurul Alimah; Agarwal, Renu; Sheikh Abdul Kadir, Siti Hamimah; Vasudevan, Sushil; Tripathy, Minaketan; Iezhitsa, Igor; Mohammad Daher, Aqil; Ibrahim, Mohd Ikraam; Mohd Ismail, Nafeeza

2017-01-01

Cataract, a leading cause of blindness, is of special concern in diabetics as it occurs at earlier onset. Polyol accumulation and increased oxidative-nitrosative stress in cataractogenesis are associated with NFκB activation, iNOS expression, ATP depletion, loss of ATPase functions, calpain activation and proteolysis of soluble to insoluble proteins. Tocotrienol was previously shown to reduce lens oxidative stress and inhibit cataractogenesis in galactose-fed rats. In current study, we investigated anticataract effects of topical tocotrienol and possible mechanisms involved in streptozotocin-induced diabetic rats. Diabetes was induced in Sprague Dawley rats by intraperitoneal injection of streptozotocin. Diabetic rats were treated with vehicle (DV) or tocotrienol (DT). A third group consists of normal, non-diabetic rats were treated with vehicle (NV). All treatments were given topically, bilaterally, twice daily for 8 weeks with weekly slit lamp monitoring. Subsequently, rats were euthanized and lenses were subjected to estimation of polyol accumulation, oxidative-nitrosative stress, NFκB activation, iNOS expression, ATP levels, ATPase activities, calpain activity and total protein levels. Cataract progression was delayed from the fifth week onwards in DT with lower mean of cataract stages compared to DV group (p<0.01) despite persistent hyperglycemia. Reduced cataractogenesis in DT group was accompanied with lower aldose reductase activity and sorbitol level compared to DV group (p<0.01). DT group also showed reduced NFκB activation, lower iNOS expression and reduced oxidative-nitrosative stress compared to DV group. Lenticular ATP and ATPase and calpain 2 activities in DT group were restored to normal. Consequently, soluble to insoluble protein ratio in DT group was higher compared to DV (p<0.05). In conclusion, preventive effect of topical tocotrienol on development of cataract in STZ-induced diabetic rats could be attributed to reduced lens aldose reductase activity, polyol levels and oxidative-nitrosative stress. These effects of tocotrienol invlove reduced NFκB activation, lower iNOS expression, restoration of ATP level, ATPase activities, calpain activity and lens protein levels. PMID:28350848

Reduction of oxidative-nitrosative stress underlies anticataract effect of topically applied tocotrienol in streptozotocin-induced diabetic rats.

PubMed

Abdul Nasir, Nurul Alimah; Agarwal, Renu; Sheikh Abdul Kadir, Siti Hamimah; Vasudevan, Sushil; Tripathy, Minaketan; Iezhitsa, Igor; Mohammad Daher, Aqil; Ibrahim, Mohd Ikraam; Mohd Ismail, Nafeeza

2017-01-01

Cataract, a leading cause of blindness, is of special concern in diabetics as it occurs at earlier onset. Polyol accumulation and increased oxidative-nitrosative stress in cataractogenesis are associated with NFκB activation, iNOS expression, ATP depletion, loss of ATPase functions, calpain activation and proteolysis of soluble to insoluble proteins. Tocotrienol was previously shown to reduce lens oxidative stress and inhibit cataractogenesis in galactose-fed rats. In current study, we investigated anticataract effects of topical tocotrienol and possible mechanisms involved in streptozotocin-induced diabetic rats. Diabetes was induced in Sprague Dawley rats by intraperitoneal injection of streptozotocin. Diabetic rats were treated with vehicle (DV) or tocotrienol (DT). A third group consists of normal, non-diabetic rats were treated with vehicle (NV). All treatments were given topically, bilaterally, twice daily for 8 weeks with weekly slit lamp monitoring. Subsequently, rats were euthanized and lenses were subjected to estimation of polyol accumulation, oxidative-nitrosative stress, NFκB activation, iNOS expression, ATP levels, ATPase activities, calpain activity and total protein levels. Cataract progression was delayed from the fifth week onwards in DT with lower mean of cataract stages compared to DV group (p<0.01) despite persistent hyperglycemia. Reduced cataractogenesis in DT group was accompanied with lower aldose reductase activity and sorbitol level compared to DV group (p<0.01). DT group also showed reduced NFκB activation, lower iNOS expression and reduced oxidative-nitrosative stress compared to DV group. Lenticular ATP and ATPase and calpain 2 activities in DT group were restored to normal. Consequently, soluble to insoluble protein ratio in DT group was higher compared to DV (p<0.05). In conclusion, preventive effect of topical tocotrienol on development of cataract in STZ-induced diabetic rats could be attributed to reduced lens aldose reductase activity, polyol levels and oxidative-nitrosative stress. These effects of tocotrienol invlove reduced NFκB activation, lower iNOS expression, restoration of ATP level, ATPase activities, calpain activity and lens protein levels.

[Value the correction of corneal astigmatism in cataract surgery].

PubMed

Wang, J; Cao, Y X

2018-05-11

The aim of modern micro-incision phacoemulsification combined with foldable intraocular lens implantation and femtosecond laser-assisted cataract surgery is evolving from a simple pursuit of recuperation to a refractive procedure, which involves the correction of ametropia according to preoperative and postoperative refractive conditions, especially corneal astigmatism, in order to achieve the goal of optimized postoperative uncorrected full range of vision. Nowadays, due attention to the effect of preoperative corneal astigmatism, surgery-induced astigmatism and residual astigmatism after operation is lacked, which affect postoperative visual acuity significantly. There are many effective ways to reduce corneal astigmatism after cataract surgery including selecting appropriate size and location of clear corneal incision, employing astigmatism keratotomy and the implantation of Toric intraocular lenses, which need to be appropriately applied and popularized. At the same time, surgical indications, predictability and safety should also be taken into account. (Chin J Ophthalmol, 2018, 54: 321-323) .

Ocular residual astigmatism (ORA) in pre-cataract eyes prior to and after refractive lens exchange.

PubMed

Katz, Toam; Steinberg, Johannes; Druchkiv, Vasyl; Linke, Stephan J; Frings, Andreas

2017-08-01

The purpose of this study was to analyze ocular residual astigmatism (ORA) before and after implantation of two different optical types of non-toric multifocal intraocular lenses (MIOL) in pre-cataract patients. This retrospective cohort study analyzed 72 eyes from 72 consecutive patients after MIOL surgery . To investigate magnitude and axis of astigmatic changes, the concepts of true corneal astigmatism and Alpins vector method were applied. There were no statistically significant between-group differences prior to surgery. The mean refractive surgically induced astigmatism (RSIA) (P = 0.063) and the topographic SIA (TSIA) (P = 0.828) did not differ significantly between the lenses, and the summated vector mean for ORA was reduced in terms of magnitude by approximately 0.30 Diopter. ORA in pseudophakic eyes mainly results from the posterior corneal surface and less from IOL tilting, postoperative posterior capsule shrinkage, or secondary cataract.

Effects of green and red light in βL-crystallin and ovalbumin

PubMed Central

Espinoza, J. Horacio; Reynaga-Hernández, Elizabeth; Ruiz-García, Jaime; Montero-Morán, Gabriela; Sanchez-Dominguez, Margarita; Mercado-Uribe, Hilda

2015-01-01

The effects of visible light on biological systems have been widely studied. In particular, the alterations of blue light on the ocular lens have recently attracted much attention. Here, we present a study about the effects produced by green and red light on two different proteins: βL-crystallin and ovalbumin. Based on differential scanning calorimetry (DSC), circular dichroism (CD), dynamic light scattering (DLS), and fluorescence emission measurements, we found that both wavelengths induce structural changes in these proteins. We also observed that βL-crystallin aggregates. Our work may advance our understanding about conformational and aggregation processes in proteins subjected to visible radiation and the possible relationship with cataracts. While blue light has been considered the only harmful component in the visible espectrum, our findings show the possibility that lower energy components may be also of some concern. PMID:26656181

Featured Article: Inhibition of diabetic cataract by glucose tolerance factor extracted from yeast

PubMed Central

Cohen, Revital; Eliaz, Anat; Dovrat, Ahuva

2016-01-01

Diabetes leads to many complications; among them is the development of cataract. Hyperglycemia brings to increased polyol concentration in the lens, to glycation of lens proteins, and to elevated level of ROS (Reactive Oxygen Species) causing oxidative stress. The glucose tolerance factor (GTF) was found by several groups to decrease hyperglycemia and oxidative stress both in diabetic animals and humans. The aim of our study was to explore the damages induced by high glucose to the eye lens and to assess the protective effects of GTF both in vivo and in vitro. The in vivo study included control healthy rats, streptozotocin (STZ) diabetic untreated rats, and STZ diabetic rats orally treated with 15 doses of GTF. The diabetic untreated rats developed cataracts, whereas the development of cataract was totally or partially prevented in GTF treated animals. In vitro studies were done on bovine lenses incubated for 14 days. Half of the lenses were incubated in normal glucose conditions, and half in high glucose conditions (450 mg%). To one group of the normal or high glucose condition GTF was added. The optical quality of all the lenses was measured daily by an automated scanning laser system. The control lenses, whether with or without GTF addition, did not show any reduction in their quality. High glucose conditions induced optical damage to the lenses. Addition of GTF to high glucose conditions prevented this damage. High glucose conditions affected the activity of aldose reductase and sodium potassium ATPase in lens epithelial cell. Addition of GTF decreased the destructive changes induced by high glucose conditions. The amount of soluble cortical lens proteins was decreased and structural changes were detected in lenses incubated in high glucose medium. These changes could be prevented when GTF was added to high glucose medium. Our findings demonstrate the anticataractogenic potential of GTF. PMID:26825353

An ocular drug delivery system containing zinc diethyldithiocarbamate and HPbetaCD inclusion complex--corneal permeability, anti-cataract effects and mechanism studies.

PubMed

Wang, Siling; Li, Dexin; Ito, Yoshimasa; Liu, Xia; Zhang, Jinghai; Wu, Chunfu

2004-10-01

Our purpose was to study the formulation and anti-cataract effects of aqueous eye drops containing a high concentration of zinc diethyldithiocarbamate (Zn-DDC). A possible mechanism of the anti-cataract effect of Zn-DDC was also studied. Zn-DDC and hydroxypropyl-beta-cyclodextrin (HPbetaCD) inclusion complex (Zn-DDC/HPbetaCD) was studied using the saturation solution method and characterized by differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (IR). Suitable formulations for Zn-DDC eye drops were established by means of in-vitro trans-corneal penetration experiments. The anti-cataract effect of the selected formulation was demonstrated by the delay in lens opacity development in hereditary shumuya cataract rats (SCRs). Semiquantitative reverse transcription polymerase chain reaction (RT-PCR) was performed to study the effect of diethyldithiocarbamate (DDC), a metabolite of Zn-DDC, on the transcription inducible nitric oxide synthase (iNOS) mRNA in human lens epithelial cells (HLEC). In the presence of 22% (w/v) HPbetaCD, the solubility of Zn-DDC in water (0.2 mM) was increased almost 850 fold (to 17 mM), by the formation of Zn-DDC/HPbetaCD. The stoichiometry of Zn-DDC inclusion was 1:1. The Zn-DDC/HPbetaCD stability constant, Ks (1:1) was estimated to be 3453 M(-1). The ophthalmic preparation containing 0.1% HPMC and 0.1% poloxamer 188 (P188) exhibited better permeability than the others in-vitro, and significantly delayed cataract formation in SCRs compared with non-treated SCRs. DDC inhibits the transcription of iNOS mRNA in HLEC. We concluded that this drug delivery system increases both the drug solubility in aqueous eye drops and the permeability of drug through the rabbit cornea, by the formation of a drug-cyclodextrin inclusion complex and the addition of polymers and penetration enhancers. The preparation effectively prevented the development of cataracts in SCRs. DDC, the metabolite of Zn-DDC, may be one of the factors in the prevention of cataract formation because it inhibits the transcription of iNOS mRNA.

The anti-cataract molecular mechanism study in selenium cataract rats for baicalin ophthalmic nanoparticles.

PubMed

Li, Nan; Han, Zhenzhen; Li, Lin; Zhang, Bing; Liu, Zhidong; Li, Jiawei

2018-01-01

The objective of this study was to investigate the effects of the solid lipid nanoparticles of baicalin (BA-SLNs) on an experimental cataract model and explore the molecular mechanism combined with bioinformatics analysis. The transparency of lens was observed daily by slit-lamp and photography. Lenticular opacity was graded. Two-dimensional gel electrophoresis (2-DE) was employed to analyze the differential protein expression modes in each group. Proteins of interest were subjected to protein identification by nano-liquid chromatography tandem mass spectrometry (LC-MS/MS). Bioinformatics analysis was performed using the Ingenuity Pathway Analysis (IPA) online software to comprehend the biological implications of the proteins identified by proteomics. At the end of the sodium selenite-induced cataract progression, almost all lenses from the model group developed partial nuclear opacity; however, all lenses were clear and normal in the blank group. There was no significant difference between the BA-SLNs group and the blank group. Many protein spots were differently expressed in 2-DE patterns of total proteins of lenses from each group, and 65 highly different protein spots were selected to be identified between the BA-SLNs group and the model group. A total of 23 proteins were identified, and 12 of which were crystalline proteins. We considered crystalline proteins to play important roles in preserving the normal expression levels of proteins and the transparency of lenses. The general trend in the BA-SLN-treated lenses' data showed that BA-SLNs regulated the protein expression mode of cataract lenses to normal lenses. Our findings suggest that BA-SLNs may be a potential therapeutic agent in treating cataract by regulating protein expression and may also be a strong candidate for future clinical research.

Ethanol extract of Moringa oliefera prevents in vitro glucose induced cataract on isolated goat eye lens.

PubMed

Kurmi, Raghvendra; Ganeshpurkar, Aditya; Bansal, Divya; Agnihotri, Abhishek; Dubey, Nazneen

2014-02-01

The aim of current work was to evaluate in vitro anticataract potential of Moringa oliefera extract. Goat eye lenses were divided into 4 groups; Group served as control, Group II as toxic control, Group III and Group IV were incubated in extract (250 μg/ml and 500 μg/ml of extract of M. oliefera) Group II, III and IV were incubated in 55 mM glucose in artificial aqueous humor to induce lens opacification. Estimation of total, water soluble protein, catalase, glutathione and malondialdehyde along with photographic evaluation of lens was done. Group II (toxic control) lenses showed high amount of MDA (Malondialdehyde), soluble, insoluble protein, decreased catalase and glutathione levels, while lenses treated with Moringa oliefera extract (Group III and Group IV) showed significant (FNx01 P < 0.05) reduction in MDA and increased level of catalase, glutathione, total and soluble protein. Results of present findings suggest protective effect of Moringa oliefera in prevention of in vitro glucose induced cataract.

The Development of Countermeasures for Space Radiation Induced Adverse Health Effects

NASA Astrophysics Data System (ADS)

Kennedy, Ann

The Development of Countermeasures for Space Radiation Induced Adverse Health Effects Ann R. Kennedy Department of Radiation Oncology, University of Pennsylvania School of Medicine, 195 John Morgan Building, 3620 Hamilton Walk, Philadelphia, PA, United States 19104-6072 The development of countermeasures for radiation induced adverse health effects is a lengthy process, particularly when the countermeasure/drug has not yet been evaluated in human trials. One example of a drug developed from the bench to the clinic is the soybean-derived Bowman-Birk inhibitor (BBI), which has been developed as a countermeasure for radiation induced cancer. It was originally identified as a compound/drug that could prevent the radiation induced carcinogenic process in an in vitro assay system in 1975. The first observation that BBI could inhibit carcinogenesis in animals was in 1985. BBI received Investigational New Drug (IND) Status with the U.S. Food and Drug Administration (FDA) in 1992 (after several years of negotiation with the FDA about the potential IND status of the drug), and human trials began at that time. Phase I, II and III human trials utilizing BBI have been performed under several INDs with the FDA, and an ongoing Phase III trial will be ending in the very near future. Thus, the drug has been in development for 35 years at this point, and it is still not a prescription drug on the market which is available for human use. A somewhat less time-consuming process is to evaluate compounds that are on the GRAS (Generally Recognized as Safe) list. These compounds would include some over-the-counter medications, such as antioxidant vitamins utilized in human trials at the levels for which Recommended Dietary Allowances (RDAs) have been established. To determine whether GRAS substances are able to have beneficial effects on radiation induced adverse health effects, it is still likely to be a lengthy process involving many years to potentially decades of human trial work. The human trials necessary to demonstrate "efficacy" for a beneficial effect on the long term adverse health effects of radiation, such as the development of cancer, cataracts, etc., is expected to take particularly long periods of time. To avoid the long time delay in the development of new drugs as countermeasures for radiation induced adverse health effects, the NSBRI Center for Acute Radiation Research (CARR) is currently focused on the use of drugs that have already been approved for human use by the FDA. Currently there are no approved countermeasures for external radiation exposure by the US Army or by NASA. The appropriate medications for symptoms of the Acute Radiation Syndrome (ARS) due to exposure to solar particle event (SPE) radiation are unknown, but there are medications appropriate for ARS symptoms caused by exposure to conventional ra-diation. The Armed Forces Radiobiology Research Institute (AFRRI) has medical guidelines for ARS medications (http://www.afrri.usuhs.mil/outreach/guidance.htm#policies), as does the US Dept. of Health and Human Services (the REMM (Radiation Event Medical Manage-ment) site (http://www.remm.nlm.gov). Supportive care when ARS symptoms develop include the administration of antimicrobial agents (which can include systemic antibiotics [especially those directed at gram-negative bacteria]), antiemetic agents, antidiarrheal agents, fluids, elec-trolytes, analgesic agents and topical burn creams (Waselenko, J.K. et al. Ann. Intern. Med. 140: 1037, 2004). For nausea and vomiting, serotonin receptor antagonists (5HT3 receptor antagonists) are very effective prophylaxis. There are two drugs that have been approved by the FDA (Zofran and Kytril) for radiation induced nausea and vomiting. Kytril (granisetron) is preferred by the US Army and is currently maintained in the US National Stockpile. Both of these drugs are known to stop retching and vomiting when given either before or after irradi-ation, even when vomiting and/or retching are occurring. Immune suppression can occur due to declines in white blood cells and infection is a possibility. Of particular importance is the radiation induced decline in neutrophil counts. Methods for controlling infection during the critical neutropenic phase can be used. Investigations of the CARR grant use FDA approved drugs for ARS symptoms in animals exposed to SPE radiations. ACKNOWLEDGEMENTS: The research investigations of the CARR grant are supported by the National Space Biomedical Research Institute (NSBRI) through NASA NCC 9-58.

Characterization and prevalence of cataracts in Labrador Retrievers in The Netherlands.

PubMed

Kraijer-Huver, Ingrid M G; Gubbels, Ed J; Scholten, Janneke; Djajadiningrat-Laanen, Sylvia C; Boevé, Michael H; Stades, Frans C

2008-10-01

To assess the prevalence and distribution of types of cataract, investigate the effects of selective breeding on cataract development, and identify the relationship between posterior polar cataract and other types of cortical cataracts in Labrador Retrievers in The Netherlands. 9,017 Labrador Retrievers. Records of 18,283 ophthalmic examinations performed by veterinary ophthalmologists from 1977 through 2005 were reviewed. There were 522 dogs affected by hereditary cataracts in 1 or both eyes without progressive retinal atrophy (PRA) and 166 PRA-affected dogs with cataracts. These cataracts were divided into 3 groups: posterior polar (triangular) cataract, extensive immature and mature cataract, and a miscellaneous group. Dogs with PRA were analyzed separately. From 1980 through 2000, the prevalence of hereditary cataracts was stable at 8%. The prevalence of cataracts in offspring of cataract-affected dogs was significantly increased, compared with the prevalence in offspring of nonaffected dogs. The distribution of types of cataract was significantly different between dogs with primary cataracts and PRA-affected dogs. Dogs with posterior polar (triangular) cataracts produced affected offspring with the same distribution of types of cataracts as the entire population of primary cataract-affected dogs. Cataract development in the Labrador Retriever population in The Netherlands appears to be a predominantly genetic disorder. Posterior polar (triangular) cataracts appear to be related to other types of hereditary cataract. Although there is no conclusive evidence, it seems valid to continue exclusion of all Labrador Retrievers affected by any type of primary cataract from breeding.

[Radiation exposure during spiral-CT of the paranasal sinuses].

PubMed

Dammann, F; Momino-Traserra, E; Remy, C; Pereira, P L; Baumann, I; Koitschev, A; Claussen, C D

2000-03-01

Determination of the radiation doses in spiral CT of the paranasal sinuses using a variety of mAs values and scan protocols. CT examinations of the paranasal sinuses were performed using an Alderson-Rando phantom. Radiation dose was determined by LiF-TLD at the level of high risk organs in the head and neck region for combinations of different scan parameters (2/3, 3/3, 3/4 mm) and decreasing charges (200, 150, 100, 50, 25 mAs) on a spiral CT. Additional measurements were performed on three other CT scanners using the 2/3 mm protocol at 50 mAs, and a single slice technique (5/5 mm) on one scanner. The lowest dose values found were 1.88 mGy for the eye lenses, 1.35 mGy for the parotid gland, 0.03 mGy for the thyroid gland and 0.1 mGy for the medulla oblongata using 2 mm collimation and 3 mm table feed at 25 mAs. Maximal dose values resulted using the 3/3 mm protocol at 200 mAs (31.00 mGy for the eye lense, 0.65 mGy for the thyroid gland). There were no significant differences found between the different CT scanners. Using up-to-date CT scanners, radiation exposure may be reduced by a factor of 15-20 compared to that of conventional CT technique. Thus, the exposure of the eye lens comes to only a thousandth of the value supposedly inducing a cataract, as published by the ICRP.

Dose estimation of eye lens for interventional procedures in diagnosis

NASA Astrophysics Data System (ADS)

Liu, Yu-Rong; Huang, Chia-Yu; Hsu, Ching-Han; Hsu, Fang-Yuh

2017-11-01

The International Commission on Radiological Protection (ICRP) recommended that the equivalent dose limit for the lens of the eye be decreased from 150 mSv/y (ICRP, 2007) to 20 mSv/y averaged over five years (ICRP, 2011). How to accurately measure the eye-lens dose has, therefore, been an issue of interest recently. Interventional radiologists are at a higher risk of radiation-induced eye injury, such as cataracts, than all other occupational radiation workers. The main objective of this study is to investigate the relationship between the doses to the eye lenses of interventional radiologists measured by different commercial eye-lens dosimeters. This study measured a reference eye-lens dose, which involved placing thermoluminescent dosimeter (TLD) chips at the surface of the eye of the Rando Phantom, and the TLD chips were covered by a 3-mm-thick tissue-equivalent bolus. Commercial eye-lens dosimeters, such as a headband dosimeter and standard personnel dose badges, were placed at the positions recommended by the manufacturers. The results show that the personnel dose badge is not an appropriate dosimeter for evaluating eye-lens dose. Dose deviations for different dosimeters are discussed and presented in this study.

Radiation-induced cataracts: the Health Protection Agency's response to the ICRP statement on tissue reactions and recommendation on the dose limit for the eye lens.

PubMed

Bouffler, Simon; Ainsbury, Elizabeth; Gilvin, Phil; Harrison, John

2012-12-01

This paper presents the response of the Health Protection Agency (HPA) to the 2011 statement from the International Commission on Radiological Protection (ICRP) on tissue reactions and recommendation of a reduced dose limit for the lens of the eye. The response takes the form of a brief review of the most recent epidemiological and mechanistic evidence. This is presented together with a discussion of dose limits in the context of the related risk and the current status of eye dosimetry, which is relevant for implementation of the limits. It is concluded that although further work is desirable to quantify better the risk at low doses and following protracted exposures, along with research into the mechanistic basis for radiation cataractogenesis to inform selection of risk projection models, the HPA endorses the conclusion reached by the ICRP in their 2011 statement that the equivalent dose limit for the lens of the eye should be reduced from 150 to 20 mSv per year, averaged over a five year period, with no year's dose exceeding 50 mSv.

Results of endocapsular phacofracture debulking of hard cataracts.

PubMed

Davison, James A

2015-01-01

To present a phacoemulsification technique for hard cataracts and compare postoperative results using two different ultrasonic tip motions during quadrant removal. A phacoemulsification technique which employs in situ fracture and endocapsular debulking for hard cataracts is presented. The prospective study included 56 consecutive cases of hard cataract (LOCS III NC [Lens Opacification Classification System III, nuclear color], average 4.26), which were operated using the Infiniti machine and the Partial Kelman tip. Longitudinal tip movement was used for sculpting for all cases which were randomized to receive longitudinal or torsional/interjected longitudinal (Intelligent Phaco [IP]) strategies for quadrant removal. Measurements included cumulative dissipated energy (CDE), 3 months postoperative surgically induced astigmatism (SIA), and corneal endothelial cell density (ECD) losses. No complications were recorded in any of the cases. Respective overall and longitudinal vs IP means were as follows: CDE, 51.6±15.6 and 55.7±15.5 vs 48.6±15.1; SIA, 0.36±0.2 D and 0.4±0.2 D vs 0.3±0.2 D; and mean ECD loss, 4.1%±10.8% and 5.9%±13.4% vs 2.7%±7.8%. The differences between longitudinal and IP were not significant for any of the three categories. The endocapsular phacofracture debulking technique is safe and effective for phacoemulsification of hard cataracts using longitudinal or torsional IP strategies for quadrant removal with the Infiniti machine and Partial Kelman tip.

Morphologic features and surgically induced astigmatism of femtosecond laser versus manual clear corneal incisions.

PubMed

Zhu, Sha; Qu, Naibin; Wang, Wei; Zhu, Yanan; Shentu, Xingchao; Chen, Peiqing; Xu, Wen; Yao, Ke

2017-11-01

To compare the morphologic features and surgically induced astigmatism (SIA) between laser and manual clear corneal incisions (CCIs) after femtosecond laser-assisted cataract surgery. Eye Center, 2nd Affiliated Hospital, Medical College of Zhejiang University, Hangzhou, China. Prospective case series. Patients had femtosecond laser-assisted cataract surgery with a CCI created with the laser or manually after random allocation. The corrected distance visual acuity, corneal topography, and anterior segment optical coherence tomography were assessed at the 1-day, 1-week, 1-month, and 3-month follow-ups. The laser CCI group comprised 45 eyes and the manual CCI group, 48 eyes. The SIA was significantly lower in the manual CCI group than the laser CCI group at all visits (P < .05). At the 1-day and 1-week follow-ups, the mean CCI thickness was significantly smaller in the manual CCI group (P < .05). In the laser CCI group, the perpendicular linear distance between the external wound opening and the corneal vertex central line was statistically shorter than in the manual CCI group (P < .05). At 3 months, the SIA was correlated with the perpendicular linear distance with a Pearson correlation coefficient of -0.341 (P = .001). Femtosecond laser-created CCIs for cataract surgery caused more SIA than manually created CCIs, which could have resulted from inaccurate or uncertain corneal incision positioning of the femtosecond machine. Manual creation of CCIs is recommended in femtosecond laser-assisted cataract surgery until the locating system for the femtosecond laser incision is updated. Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Cataracts

MedlinePlus

... Oncology Oculoplastics/Orbit Refractive Management/Intervention Retina/Vitreous Uveitis Focus On Pediatric Ophthalmology ... Are Cataracts? Pediatric Cataracts Cataract Diagnosis and Treatment Cataract Surgery IOL Implants: Lens Replacement After Cataracts ...

Radiation cataracts: mechanisms involved in their long delayed occurrence but then rapid progression.

PubMed

Wolf, Norman; Pendergrass, William; Singh, Narendra; Swisshelm, Karen; Schwartz, Jeffrey

2008-02-05

This study was directed to assess the DNA damage and DNA repair response to X-ray inflicted lens oxidative damage and to investigate the subsequent changes in lens epithelial cell (LEC) behavior in vivo that led to long delayed but then rapidly developing cataracts. Two-month-old C57Bl/6 female mice received 11 Grays (Gy) of soft x-irradiation to the head only. The animals' eyes were examined for cataract status in 30 day intervals by slit lamp over an 11 month period post-irradiation. LEC migration, DNA fragment, free DNA retention, and reactive oxygen species (ROS) presence were established in the living lenses with fluorescent dyes using laser scanning confocal microscopy (LSCM). The extent and removal of initial LEC DNA damage were determined by comet assay. Immunohistochemistry was used to determine the presence of oxidized DNA and the response of a DNA repair protein in the lenses. This treatment resulted in advanced cortical cataracts that developed 5-11 months post-irradiation but then appeared suddenly within a 30 day period. The initially incurred DNA strand breaks were repaired within 30 min, but DNA damage remained as shown 72 h post-irradiation by the presence of the DNA adduct, 8-hydroxyguanosine (8-OHG), and a DNA repair protein, XRCC1. This was followed months later by abnormal behavior by LEC descendant cells with abnormal differentiation and migration patterns as seen with LSCM and fluorescent dyes. The sudden development of cortical cataracts several months post-irradiation coupled with the above findings suggests an accumulation of damaged descendants from the initially x-irradiated LECs. As these cells migrate abnormally and leave acellular lens surface sites, eventually a crisis point may arrive for lens entry of environmental O(2) with resultant ROS formation that overwhelms protection by resident antioxidant enzymes and results in the coagulation of lens proteins. The events seen in this study indicate the retention and transmission of progenitor cell DNA damage in descendant LEC. The cellular and molecular events parallel those previously reported for LSCM observations in age-related cataracts.

Radiation-induced ocular injury in the dog: a histological study.

PubMed

Ching, S V; Gillette, S M; Powers, B E; Roberts, S M; Gillette, E L; Withrow, S J

1990-08-01

Radiation-induced ocular injury secondary to treatment of nasal cancer occurs in humans and animals. Dogs with nasal carcinomas were randomized to receive 36 to 67.5 Gy in fractionated doses given in 4 weeks using a 6 MV linear accelerator. Ophthalmic examinations were performed according to a predetermined protocol and eyes were removed for histologic examination when dogs were euthanatized. The eye in the radiation field exhibited greater injury than the contralateral eye with nasal areas of the globe having more severe lesions than temporal areas. Lesions occurred in all dogs and at all doses. At 1 month or less postirradiation treatment, all dogs had blepharitis, keratoconjunctivitis and corneal epithelial atrophy. Surface lesions persisted in all eyes, becoming less severe and more chronic with time. At 3-6 months postirradiation treatment, degenerative angiopathy of retinal vessels appeared with multifocal retinal hemorrhage and mild diffuse retinal degeneration which affected outer layers first and progressed inwardly with time. At 6 months postirradiation treatment, there were cataracts, fibrosis of retinal vessel walls with loss of vascular smooth muscle, retinal hemorrhage, and mild to moderate retinal degeneration. At 1 year postirradiation treatment, retinal vessels remained sclerotic, retinal hemorrhage was less frequent, and there was moderate retinal degeneration with swelling and loss of ganglion cells. By 2 years or more postirradiation treatment, optic nerve axonal degeneration secondary to retinal changes had appeared. Tapetal and choroidal atrophy were inconsistently seen. Thus, ocular lesions at the doses received developed along a relatively predictable time course and recovery was not seen. Structures of the canine eye appear sufficiently sensitive that even relatively low total doses given in small doses per fraction cause significant long-term injury.

Assessment of Health Consequences of Steel Industry Welders' Occupational Exposure to Ultraviolet Radiation.

PubMed

Zamanian, Zahra; Mortazavi, Saied Mohammad Javad; Asmand, Ebrahim; Nikeghbal, Kiana

2015-01-01

Welding is among the most important frequently used processes in the industry with a wide range of applications from the food industry to aerospace and from precision tools to shipbuilding. The aim of this study was to assess the level of steel industry welders' exposure to ultraviolet (UV) radiation and to investigate the health impacts of these exposures. In this case-control study, we measured the intensity of UV at the workers' wrist in Fars Steel Company through manufacture of different types of heavy metal structures, using UV-meter model 666230 made by Leybold Co., from Germany. The population under the study comprised 400 people including 200 welders as the exposed group and 200 nonwelders as the unexposed group. The results of the questionnaire were analyzed using SPSS software, version 19. The average, standard deviation, maximum and minimum of the UV at the welders' wrist were 0.362, 0.346, 1.27, and 0.01 μW/cm(2), respectively. There was a significantly (P < 0.01) higher incidence of cataracts, keratoconjunctivitis, dermatitis and erythema in welders than in their nonwelders. This study showed that the time period of UV exposure in welders is higher than the permissible contact threshold level. Therefore, considering the outbreak of the eye and skin disorders in the welders, decreasing exposure time, reducing UV radiation level, and using personal protective equipment seem indispensable. As exposure to UV radiation can be linked to different types of skin cancer, skin aging, and cataract, welders should be advised to decrease their occupational exposures.

Assessment of Health Consequences of Steel Industry Welders’ Occupational Exposure to Ultraviolet Radiation

PubMed Central

Zamanian, Zahra; Mortazavi, Saied Mohammad Javad; Asmand, Ebrahim; Nikeghbal, Kiana

2015-01-01

Background: Welding is among the most important frequently used processes in the industry with a wide range of applications from the food industry to aerospace and from precision tools to shipbuilding. The aim of this study was to assess the level of steel industry welders’ exposure to ultraviolet (UV) radiation and to investigate the health impacts of these exposures. Methods: In this case–control study, we measured the intensity of UV at the workers’ wrist in Fars Steel Company through manufacture of different types of heavy metal structures, using UV-meter model 666230 made by Leybold Co., from Germany. Results: The population under the study comprised 400 people including 200 welders as the exposed group and 200 nonwelders as the unexposed group. The results of the questionnaire were analyzed using SPSS software, version 19. The average, standard deviation, maximum and minimum of the UV at the welders’ wrist were 0.362, 0.346, 1.27, and 0.01 μW/cm2, respectively. There was a significantly (P < 0.01) higher incidence of cataracts, keratoconjunctivitis, dermatitis and erythema in welders than in their nonwelders. Conclusions: This study showed that the time period of UV exposure in welders is higher than the permissible contact threshold level. Therefore, considering the outbreak of the eye and skin disorders in the welders, decreasing exposure time, reducing UV radiation level, and using personal protective equipment seem indispensable. As exposure to UV radiation can be linked to different types of skin cancer, skin aging, and cataract, welders should be advised to decrease their occupational exposures. PMID:26900437

Reactive Oxygen Species and the Aging Eye: Specific Role of Metabolically Active Mitochondria in Maintaining Lens Function and in the Initiation of the Oxidation-Induced Maturity Onset Cataract--A Novel Platform of Mitochondria-Targeted Antioxidants With Broad Therapeutic Potential for Redox Regulation and Detoxification of Oxidants in Eye Diseases.

PubMed

Babizhayev, Mark A; Yegorov, Yegor E

2016-01-01

The aging eye appears to be at considerable risk from oxidative stress. A great deal of research indicates that dysfunctional mitochondria are the primary site of reactive oxygen species (ROS). More than 95% of O2 produced during normal metabolism is generated by the electron transport chain in the inner mitochondrial membrane. Mitochondria are also the major target of ROS. Cataract formation, the opacification of the eye lens, is one of the leading causes of human blindness worldwide, accounting for 47.8% of all causes of blindness. Cataracts result from the deposition of aggregated proteins in the eye lens and lens fiber cell plasma membrane damage, which causes clouding of the lens, light scattering, and obstruction of vision. ROS-induced damage in the lens cell may consist of oxidation of proteins, DNA damage, and/or lipid peroxidation, all of which have been implicated in cataractogenesis. This article is an attempt to integrate how mitochondrial ROS are altered in the aging eye along with those protective and repair therapeutic systems believed to regulate ROS levels in ocular tissues and how damage to these systems contributes to age-onset eye disease and cataract formation. Mitochondria-targeted antioxidants might be used to effectively prevent ROS-induced oxidation of lipids and proteins in the inner mitochondrial membrane in vivo. As a result of the combination of weak metal chelating, OH and lipid peroxyl radicals scavenging, reducing activities to liberated fatty acid, and phospholipid hydroperoxides, carnosine and carcinine appear to be physiological antioxidants able to efficiently protect the lipid phase of biologic membranes and aqueous environments and act as the antiapoptotic natural drug compounds The authors developed and patented the new ophthalmic compositions, including N-acetylcarnosine, acting as a prodrug of naturally targeted to mitochondria L-carnosine endowed with pluripotent antioxidant activities combined with mitochondria-targeted rechargeable antioxidant (either MitoVit E, Mito Q, or SkQs) as a potent medicine to treat ocular diseases. Such specificity is explained by the fact that developed compositions might be used to effectively prevent ROS-induced oxidation of lipids and proteins in the inner mitochondrial membrane in vivo and outside mitochondria in the cellular and tissue structures of the lens and eye compartments. Mitochondrial targeting of compounds with universal types of antioxidant activity represents a promising approach for treating a number of ROS-related ocular diseases of the aging eye and can be implicated in the management of cataracts.

Methotrimeprazine-induced Corneal Deposits and Cataract Revealed by Urine Drug Profiling Test

PubMed Central

Kim, Seong Taeck; Kim, Joon Mo; Kim, Won Young; Choi, Gwang Ju

2010-01-01

Two schizophrenic patients who had been taking medication for a long period presented with visual disturbance of 6-month duration. Slit-lamp examination revealed fine, discrete, and brownish deposits on the posterior cornea. In addition, bilateral star-shaped anterior subcapsular lens opacities, which were dense, dust-like granular deposits, were noted. Although we strongly suspected that the patient might have taken one of the drugs of the phenothiazine family, we were unable to obtain a history of medications other than haloperidol and risperidone, which were taken for 3 yr. We performed a drug profiling test using urine samples and detected methotrimeprazine. The patient underwent surgery for anterior subcapsular lens opacities. Visual acuity improved in both eyes, but the corneal deposits remained. We report an unusual case of methotrimeprazine-induced corneal deposits and cataract in a patient with psychosis, identified by using the urine drug profiling test. PMID:21060765

Is the current public health message on UV exposure correct?

PubMed Central

Lucas, Robyn M.; Repacholi, Mike H.; McMichael, Anthony J.

2006-01-01

Current sun safety messages stress the importance of sun protection in avoiding the consequences of excessive exposure to ultraviolet radiation (UVR), such as skin cancers, cataracts and other eye diseases, and viral infections caused by UV-induced immunosuppression. However, adequate exposure to UVR has an important role in human health, primarily through UV-induced production of vitamin D, a hormone essential to bone health. Vitamin D insufficiency may be associated with increased risks of some cancers, autoimmune diseases and mental health disorders such as schizophrenia. Here, we review the evolution of current sun exposure practices and sun-safe messages and consider not only the benefits, but also the detrimental effects that such messages may have. UVR-induced vitamin D production can be inhibited by factors such as deep skin pigmentation, indoor lifestyles, older age, sun avoidance behaviours and clothing habits that limit skin exposure, with deleterious consequences for health. There is some early evidence that sun-safe messages are beginning to cause a decrease in skin cancer rates in young people. After the widespread promotion of sun safety, it may now be appropriate to refine public health messages to take better account of variations between groups and their susceptibility to the dangers and benefits of sun exposure. PMID:16799733

Autosomal dominant congenital nuclear cataracts in strain 13/N guinea pigs.

PubMed

Amsbaugh, D F; Stone, S H

1984-01-01

Bilateral cataracts observed in the eyes of a 13/N guinea pig and one of her two offspring led to studies to determine the nature of this cataract and its possible heritability. The cataract was determined to be of the nuclear type, was congenital, and apparently transmitted by a single autosomal dominant gene. The cataractous condition of the mother had no effect on the percentage of litters containing stillborns. The cataractous condition of the offspring had no effect on their viability in utero, i.e., there was no greater incidence of stillborns among cataractous than among non-cataractous offspring. The birthweights of the cataractous animals were lower, but not significantly, than those of their non-cataractous littermates; however, the survivability to weaning of the cataractous offspring was reduced significantly when compared to their non-cataractous siblings.

Modified cataract surgery with telescopic magnification for patients with age-related macular degeneration.

PubMed

Iizuka, Megumi; Gorfinkel, John; Mandelcorn, Mark; Lam, Wai-Ching; Devenyi, Robert; Markowitz, Samuel N

2007-12-01

The most desirable effect following cataract surgery in the presence of age-related macular degeneration (AMD) is to obtain an improvement in distance resolution acuity, and the only optical solution to this is the use of telescopic magnification. The purpose of the study was to develop and verify the clinical utility of inducing low-grade telescopic magnification (<33%) at the time of cataract surgery by the choice of an appropriate intraocular lens power and spectacle glasses in patients with AMD and cataract. The design was a prospective, nonrandomized, interventional case series involving 6 patients aged 74-86 (mean 80; SD 4) years with AMD and cataract. Participants were males and females, equal in number, who had visual acuity of less than 20/400 in the weaker eye. Standard cataract surgery was performed in the weaker eye. The power of the intraocular lens was derived from the reduced Gullstrand model of the eye in such a way that at the intraocular lens plane a minus lens was created, which, together with a plus lens in matching glasses, formed a Galilean telescopic system with magnification of up to 33%. Outcome measures were visual acuity, contrast sensitivity, and activities of daily living (ADL) scores. The mean power of the implanted intraocular lenses was 6.31 (SD 2.42) diopters and, according to the theoretical derivations, achieved magnification between 20% and 30% (mean 26%; SD 4.92%). Visual acuity improved for the group from a mean of 20/525 (logMAR 1.48; SD 0.13) to a mean of 20/290 (logMAR 1.20; SD 0.21). Contrast sensitivity improved significantly (p < 0.001) only in the lower spatial frequencies. Postoperatively, ADL scores improved significantly in all patients except one. At the end of the follow-up period, 3 patients reported that they would like to proceed with similar surgery for the other eye. An optimal surgical telescopic device based on low-grade telescopic magnification may improve functional vision for usage in all tasks in AMD patients. All patients from this study were satisfied following surgery and viewed study outcomes as positive and beneficial, and some patients responded with enthusiasm. Surgeons are encouraged to use this modified technique of cataract surgery in low-vision patients with AMD and cataract.

Special Issue: 4th International Workshop on Space Radiation (IWSRR)

NASA Technical Reports Server (NTRS)

Cucinotta, Francis A.

2007-01-01

This special issue of the journal "Radiation and Environmental Biophysics" contains 20 peer-reviewed papers contributed by leading space radiation researcher's world-wide attending the 4th IWSRR. Manuscripts cover a broad range of topics ranging from radiation environments and transport in shielding and planetary surfaces to new results in understanding the biological effects of protons and high-charge and energy (HZE) nuclei on the risk of cancer, and degenerative diseases such as central nervous system effects, heart disease, and cataracts. The issue provides a snapshot of the state-of-the-art of the research in this field, demonstrating both the important results gathered in the past few years with experiments at accelerators, and the need for more research to quantify the risk and develop countermeasures.

[Multifocal intraocular lenses. A review].

PubMed

Auffarth, G U; Dick, H B

2001-02-01

Modern cataract surgery has developed tremendously during the past 10-15 years. Improved surgical techniques, as well as improved implant materials and designs, have enlarged patient profiles and indications for cataract surgery. This also created much higher expectations from the patients' site. The loss of accommodation is loss of quality of life for presbyopic and especially young pseudophakic patients. Therefore cataract surgery with multifocal IOL implantation is not only of academic interest, but reflects demands and expectations of our patients. Multifocal IOLs have been implanted since 1986, starting with 2-3 zone refractive and diffractive designs. Due to surgical techniques of that time MIOL decentration and surgically induced astigmatism were possible complications. In addition reduced contrast sensitivity and increased glare were common problems of MIOL because of their optical principles. New developments in this field in recent years such as the multizonal, progressive refractive MIOL in combination with improved surgical techniques have overcome those initial problems. Therefore, modern multifocal IOLs can be considered not only for correction of aphakia but also for refractive purposes.

Cataract and its surgery in Fiji.

PubMed

Brian, Garry; Ramke, Jacqueline; Szetu, John; Qoqonokana, Mundi Qalo

2011-07-01

To characterize cataract and its surgery among adults aged ≥40 years in Fiji. Population-based cross-sectional survey using multistage cluster random sampling. 1381 (= 73.0% participation); eight provinces on Viti Levu. Interview-based questionnaire; visual acuity measured; autorefraction; dilated ocular examination. Prevalence; predictors; surgical outcomes. Being Indian (P = 0.001), elderly (P < 0.001), and previous/current smoker (P = 0.036) were predictive of at least one unoperated vision-impairing or operated cataract. Gender (P = 0.062) and diabetes (P = 0.384) were not. Unoperated cataract (predominantly nucleosclerosis) was the second most frequent (25.0%) cause of low vision (<6/18, ≥6/60) and commonest (71.1%) of blindness (<6/60). Ethnicity-gender-age-domicile adjusted and extrapolating to the Fiji population aged ≥40 years, prevalence of cataract-induced low vision and blindness were each 1.7% (95% confidence interval [CI] 1.0-2.4%). At least one eye of 4.6% and both of 1.8% participants had surgery (86.4% extracapsular). Gender (P = 0.213), age (P = 0.472) and rural/urban domicile (P = 0.895) were not predictors of surgery among those who required it in at least one eye. After intraocular lens surgery: 50.7% had pupillary posterior capsular opacification; mean spherical equivalent was -1.37 ± 1.95D (range, -6.38 to +2.25D); mean cylindrical error was 2.31 ± 1.75D (range, 0.0 to 8.75D); ≥N8 for 39.5%; ≥6/18 for 56.6%; <6/60 for 19.7%, with 2.6% no light perception. Ethnicity-gender-age-domicile adjusted and extrapolating to the Fiji population aged ≥40 years, Cataract Surgical Coverage (Person) was 47.5% (95%CI 29.2-65.8%) at <6/18, and 65.2% (95%CI 37.8-92.6%) at <6/60. Fiji cataract services and outcomes compare favourably with those of neighbouring Papua New Guinea and Timor Leste. © 2011 The Authors. Clinical and Experimental Ophthalmology © 2011 Royal Australian and New Zealand College of Ophthalmologists.

Change in corneal aberrations after cataract surgery with 2 types of aspherical intraocular lenses.

PubMed

Marcos, Susana; Rosales, Patricia; Llorente, Lourdes; Jiménez-Alfaro, Ignacio

2007-02-01

To study the effect of cataract surgery through 3.2 mm superior incisions on corneal aberrations with 2 types of monofocal intraocular lenses (IOLs) with an aspherical design. Instituto de Optica, Consejo Superior de Investigaciones Científicas, and Fundación Jiménez Díaz, Madrid, Spain. Corneal topography of 43 eyes was obtained before and after small corneal incision cataract surgery. Twenty-two eyes had implantation of a Tecnis Z9000 silicone IOL (Advanced Medical Optics) and 21 had implantation of an AcrySof IQ SN60WF acrylic IOL (Alcon Research Labs) using the recommended injector for each IOL type. The intended incision size (3.2 mm) was similar in the 2 groups. Corneal aberrations were estimated using custom-developed algorithms (based on ray tracing) for 10.0 mm and 5.0 mm pupils. Comparisons between preoperative and postoperative measurements and across the groups were made for individual Zernike terms and root-mean-square (RMS) wavefront error. The RMS (excluding tilt and defocus) did not change in the AcrySof IQ group and increased significantly in the Tecnis group with the 10.0 mm and 5.0 mm pupil diameters. Spherical aberration and coma-like terms did not change significantly; however, vertical astigmatism, vertical trefoil, and vertical tetrafoil changed significantly with surgery with the 10.0 mm and 5.0 mm pupil diameters (P<.0005). The induced wave aberration pattern for 3rd- and higher-order aberrations consistently showed a superior lobe, resulting from a combination of positive vertical trefoil (Z(3)(-3)) and negative tetrafoil (Z(4)(4)). The mean vertical astigmatism increased by 2.47 microm +/- 1.49 (SD) and 1.74 +/- 1.44 microm, vertical trefoil increased by 1.81 +/- 1.19 microm and 1.20 +/- 1.34 microm, and tetrafoil increased by -1.10 +/- 0.78 microm and -0.89 +/- 0.68 microm in the Tecnis group and AcrySof IQ group, respectively. There were no significant differences between the corneal aberrations in the 2 postoperative groups, although there was a tendency toward more terms or orders changing statistically significantly in the Tecnis group, which had slightly higher amounts of induced aberrations. Cataract surgery with a small superior incision induced consistent and significant changes in several corneal Zernike terms (vertical astigmatism, trefoil, and tetrafoil), resulting in a significantly increased overall corneal RMS wavefront error. These results can be used to improve predictions of optical performance with new IOL designs using computer eye models and identify the potentially different impact of incision strategies on cataract surgery.

Microcoaxial cataract surgery outcomes: comparison of 1.8 mm system and 2.2 mm system.

PubMed

Lee, Kyung-Min; Kwon, Hyung-Goo; Joo, Choun-Ki

2009-05-01

To compare clinical outcomes of a 1.8 mm and a 2.2 mm microcoaxial cataract surgery system. Department of Ophthalmology and Visual Science, Kangnam St. Mary's Hospital, College of Medicine, Catholic University of Korea, Seoul, Korea. In a prospective study, eyes were randomly selected to have phacoemulsification using a Stellaris system or an Intrepid Infiniti system. The initial incision size was 1.8 mm and 2.2 mm, respectively. Measured intraoperative parameters included phacoemulsification time, mean cumulative dissipated ultrasound energy (CDE), change in incision size at each step of surgery, and total volume of balanced salt solution (BSS) used. The best corrected visual acuity (BCVA), corneal astigmatism, corneal thickness, and endothelial cell count were evaluated preoperatively and postoperatively. The study evaluated 86 eyes of 78 patients (43 eyes in each group). There were no significant differences in postoperative BCVA, surgically induced astigmatism, or amount of BSS used between the 2 systems (P >.05). However, for high-density cataracts, the 1.8 mm group had a greater change between the initial incision size and the incision size after phacoemulsification (P = .019, nuclear opalescence [NO] NO3; P = .001, NO4), a longer phacoemulsification time (P = .013, NO3), greater mean CDE (P = .005, NO3; P = .001, NO4), and greater corneal endothelial cell loss (P = .003, NO4). Both systems were safe and effective in microcoaxial phacoemulsification. The 1.8 mm system performed better with cortical-type cataract and the 2.2 mm system, with high-density nuclear-type cataract.

Results of endocapsular phacofracture debulking of hard cataracts

PubMed Central

Davison, James A

2015-01-01

Purpose/aim of the study To present a phacoemulsification technique for hard cataracts and compare postoperative results using two different ultrasonic tip motions during quadrant removal. Materials and methods A phacoemulsification technique which employs in situ fracture and endocapsular debulking for hard cataracts is presented. The prospective study included 56 consecutive cases of hard cataract (LOCS III NC [Lens Opacification Classification System III, nuclear color], average 4.26), which were operated using the Infiniti machine and the Partial Kelman tip. Longitudinal tip movement was used for sculpting for all cases which were randomized to receive longitudinal or torsional/interjected longitudinal (Intelligent Phaco [IP]) strategies for quadrant removal. Measurements included cumulative dissipated energy (CDE), 3 months postoperative surgically induced astigmatism (SIA), and corneal endothelial cell density (ECD) losses. Results No complications were recorded in any of the cases. Respective overall and longitudinal vs IP means were as follows: CDE, 51.6±15.6 and 55.7±15.5 vs 48.6±15.1; SIA, 0.36±0.2 D and 0.4±0.2 D vs 0.3±0.2 D; and mean ECD loss, 4.1%±10.8% and 5.9%±13.4% vs 2.7%±7.8%. The differences between longitudinal and IP were not significant for any of the three categories. Conclusion The endocapsular phacofracture debulking technique is safe and effective for phacoemulsification of hard cataracts using longitudinal or torsional IP strategies for quadrant removal with the Infiniti machine and Partial Kelman tip. PMID:26203213

NASCA Report 2: Longitudinal Study of Relationship of Exposure to Space Radiation and Risk of Lens Opacity

NASA Technical Reports Server (NTRS)

Chylack, Leon T., Jr.; Peterson, Leif E.; Feiveson, Alan H.; Tung, William H.; Wear, Mary L.; Marak, Lisa J.; Hardy, Dale S.; Cucinotta, Francis A.

2011-01-01

The NASA Study of Cataract in Astronauts (NASCA) was a five-year longitudinal study of the effect of space radiation exposure on the severity/progression of nuclear (N), cortical (C), and posterior subcapsular (PSC) lens opacities. It began in 2003 and was completed in December, 2009. Participants included 171 consenting astronauts who flew at least one mission in space, and comparison subjects consisted of three groups, a) 53 astronauts who had not flown in space, b) 95 military aircrew personnel, and c) 99 non-aircrew, ground-based subjects.

Induction and repair of DNA strand breaks in bovine lens epithelial cells after high LET irradiation

NASA Astrophysics Data System (ADS)

Baumstark-Khan, C.; Heilmann, J.; Rink, H.

The lens epithelium is the initiation site for the development of radiation induced cataracts. Radiation in the cortex and nucleus interacts with proteins, while in the epithelium, experimental results reveal mutagenic and cytotoxic effects. It is suggested that incorrectly repaired DNA damage may be lethal in terms of cellular reproduction and also may initiate the development of mutations or transformations in surviving cells. The occurrence of such genetically modified cells may lead to lens opacification. For a quantitative risk estimation for astronauts and space travelers it is necessary to know the relative biological effectiveness (RBE), because the spacial and temporal distribution of initial physical damage induced by cosmic radiation differ significantly from that of X-rays. RBEs for the induction of DNA strand breaks and the efficiency of repair of these breaks were measured in cultured diploid bovine lens epithelial cells exposed to different LET irradiation to either 300 kV X-rays or to heavy ions at the UNILAC accelerator at GSI. Accelerated ions from Z=8 (O) to Z=92 (U) were used. Strand breaks were measured by hydroxyapatite chromatography of alkaline unwound DNA (overall strand breaks). Results showed that DNA damage occurs as a function of dose, of kinetic energy and of LET. For particles having the same LET the severity of the DNA damage increases with dose. For a given particle dose, as the LET rises, the numbers of DNA strand breaks increase to a maximum and then reach a plateau or decrease. Repair kinetics depend on the fluence (irradiation dose). At any LET value, repair is much slower after heavy ion exposure than after X-irradiation. For ions with an LET of less than 10,000 keV μ -1 more than 90 percent of the strand breaks induced are repaired within 24 hours. At higher particle fluences, especially for low energetic particles with a very high local density of energy deposition within the particle track, a higher proportion of non-rejoined breaks is found, even after prolonged periods of incubation. At the highest LET value (16,300 keV μ -1 no significant repair is observed. These LET-dependencies are consistent with the current mechanistic model for radiation induced cataractogenesis which postulates that genomic damage to the surviving fraction of epithelial cells is responsible for lens opacification.

Ethanol extract of Moringa oliefera prevents in vitro glucose induced cataract on isolated goat eye lens

PubMed Central

Kurmi, Raghvendra; Ganeshpurkar, Aditya; Bansal, Divya; Agnihotri, Abhishek; Dubey, Nazneen

2014-01-01

Aim of Study: The aim of current work was to evaluate in vitro anticataract potential of Moringa oliefera extract. Materials and Methods: Goat eye lenses were divided into 4 groups; Group served as control, Group II as toxic control, Group III and Group IV were incubated in extract (250 μg/ml and 500 μg/ml of extract of M. oliefera) Group II, III and IV were incubated in 55 mM glucose in artificial aqueous humor to induce lens opacification. Estimation of total, water soluble protein, catalase, glutathione and malondialdehyde along with photographic evaluation of lens was done. Results: Group II (toxic control) lenses showed high amount of MDA (Malondialdehyde), soluble, insoluble protein, decreased catalase and glutathione levels, while lenses treated with Moringa oliefera extract (Group III and Group IV) showed significant (* P < 0.05) reduction in MDA and increased level of catalase, glutathione, total and soluble protein. Conclusion: Results of present findings suggest protective effect of Moringa oliefera in prevention of in vitro glucose induced cataract. PMID:24008789

Dosimetric and Late Radiation Toxicity Comparison Between Iodine-125 Brachytherapy and Stereotactic Radiation Therapy for Juxtapapillary Choroidal Melanoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krema, Hatem, E-mail: htmkrm19@yahoo.com; Heydarian, Mostafa; Beiki-Ardakani, Akbar

2013-07-01

Purpose: To compare the dose distributions and late radiation toxicities for {sup 125}I brachytherapy (IBT) and stereotactic radiation therapy (SRT) in the treatment of juxtapapillary choroidal melanoma. Methods: Ninety-four consecutive patients with juxtapapillary melanoma were reviewed: 30 have been treated with IBT and 64 with SRT. Iodine-125 brachytherapy cases were modeled with plaque simulator software for dosimetric analysis. The SRT dosimetric data were obtained from the Radionics XKnife RT3 software. Mean doses at predetermined intraocular points were calculated. Kaplan-Meier estimates determined the actuarial rates of late toxicities, and the log–rank test compared the estimates. Results: The median follow-up was 46more » months in both cohorts. The 2 cohorts were balanced with respect to pretreatment clinical and tumor characteristics. Comparisons of radiation toxicity rates between the IBT and SRT cohorts yielded actuarial rates at 50 months for cataracts of 62% and 75% (P=.1), for neovascular glaucoma 8% and 47% (P=.002), for radiation retinopathy 59% and 89% (P=.0001), and for radiation papillopathy 39% and 74% (P=.003), respectively. Dosimetric comparisons between the IBT and SRT cohorts yielded mean doses of 12.8 and 14.1 Gy (P=.56) for the lens center, 17.6 and 19.7 Gy (P=.44) for the lens posterior pole, 13.9 and 10.8 Gy (P=.30) for the ciliary body, 61.9 and 69.7 Gy (P=.03) for optic disc center, and 48.9 and 60.1 Gy (P<.0001) for retina at 5-mm distance from tumor margin, respectively. Conclusions: Late radiation-induced toxicities were greater with SRT, which is secondary to the high-dose exposure inherent to the technique as compared with IBT. When technically feasible, IBT is preferred to treat juxtapapillary choroidal melanoma.« less

Characterizing a Rat Brca2 Knockout Model

DTIC Science & Technology

2007-05-01

synechiae (adhesion of iris to lens), and anterior segment dysgenesis (adhesion of lens to cornea). The cataractous lens cells extend circumferentially...around the lens capsule to the posterior (arrowheads). ac, anterior chamber; c, cornea; i, iris ; l, lens; lc, lens capsule; r, retina; m, mineralization...to DSB forma - tion, chromosomal damage, and cell death resulting from ionizing radiation (reviewed by Pellegrini and Venkitaraman, 2004). Evidence from

Alterations in lenticular proteins during ageing and selenite-induced cataractogenesis in Wistar rats

PubMed Central

Sakthivel, Muniyan; Elanchezhian, Rajan; Thomas, Philip A.

2010-01-01

Purpose To determine putative alterations in the major lenticular proteins in Wistar rats of different ages and to compare these alterations with those occurring in rats with selenite-induced cataract. Methods Lenticular transparency was determined by morphological examination using slit-lamp biomicroscopy. Alterations in lenticular protein were determined by sodium dodecyl sulfate-PAGE (SDS–PAGE) and confirmed immunologically by western blot. Results Morphological examination did not reveal observable opacities in the lenses of the rats of different age groups; however, dense nuclear opacities were noted in lenses of rats in the selenite-cataract group. Western blot assays revealed age-related changes in soluble and urea-soluble lenticular proteins. Decreased αA- and βB1-crystallins in the soluble fraction and aggregation of αA-crystallin, in addition to the degraded fragment of βB1-crystallin, in the urea-soluble fraction appeared to occur in relation to increasing age of the rats from which the lenses were taken; similarly, cytoskeletal proteins appeared to decline with increasing age. The lenses from rats in the selenite-cataract group exhibited similar changes, except that there was also high molecular weight aggregation of αA-crystallin. Conclusions The results of this study suggest that there is loss, as well as aggregation, of αA-crystallin in the aging rat lens, although there is no accompanying loss of lenticular transparency. PMID:20300567

Alterations in lenticular proteins during ageing and selenite-induced cataractogenesis in Wistar rats.

PubMed

Sakthivel, Muniyan; Elanchezhian, Rajan; Thomas, Philip A; Geraldine, Pitchairaj

2010-03-16

To determine putative alterations in the major lenticular proteins in Wistar rats of different ages and to compare these alterations with those occurring in rats with selenite-induced cataract. Lenticular transparency was determined by morphological examination using slit-lamp biomicroscopy. Alterations in lenticular protein were determined by sodium dodecyl sulfate-PAGE (SDS-PAGE) and confirmed immunologically by western blot. Morphological examination did not reveal observable opacities in the lenses of the rats of different age groups; however, dense nuclear opacities were noted in lenses of rats in the selenite-cataract group. Western blot assays revealed age-related changes in soluble and urea-soluble lenticular proteins. Decreased alphaA- and betaB1-crystallins in the soluble fraction and aggregation of alphaA-crystallin, in addition to the degraded fragment of betaB1-crystallin, in the urea-soluble fraction appeared to occur in relation to increasing age of the rats from which the lenses were taken; similarly, cytoskeletal proteins appeared to decline with increasing age. The lenses from rats in the selenite-cataract group exhibited similar changes, except that there was also high molecular weight aggregation of alphaA-crystallin. The results of this study suggest that there is loss, as well as aggregation, of alphaA-crystallin in the aging rat lens, although there is no accompanying loss of lenticular transparency.

Bilateral cataract extraction with posterior chamber intraocular lens implantation simultaneous in pediatric cataracts.

PubMed

Caça, Ihsan; Sakalar, Yildirim Bayezit; Ari, Seyhmus; Alakus, Fuat; Dogan, Eyüp

2008-01-01

We evaluated the results of simultaneous bilateral cataract extraction with intraocular lens (IOL) inplantation 32 pediatric cataract patients. Simultaneous cataract extraction and posterior capsulotomy with anterior vitrectomy and IOL implantation is an effective and safe procedure in bilateral pediatric cataracts treatment.

Delayed effects of proton irradiation in Macaca Mulatta (22-year summary)

NASA Astrophysics Data System (ADS)

Woods, D. H.; Hardy, K. A.; Cox, A. B.; Salmon, Y. L.; Yochmowitz, M. G.; Cordts, R. E.

1989-05-01

Lifetime observations on a group of rhesus monkeys indicate that life expectancy loss from exposure to protons in the energy range encountered in the Van Allen belts and solar proton events can be correlated with the dose and energy of radiation. The primary cause of life shortening is nonleukemic cancers. Radiation also increased the rise of endometriosis (an abnormal proliferation of the lining of the uterus in females). Other effects associated with radiation exposures are lowered glucose tolerance and increased incidence of cataracts. Calculations of the relative risk of fatal cancers in the irradiated subjects reveal that the total body surface dose required to double the risk of death from cancer over a 20-year post exposure period varies with the linear energy transfer (LET) of the radiation. The ability to determine the integrated dose and LET spectrum in space radiation exposures of humans is, therefore, critical to the assessment of lifetime cancer risk.

End-To-End Risk Assesment: From Genes and Protein to Acceptable Radiation Risks for Mars Exploration

NASA Technical Reports Server (NTRS)

Cucinotta, Francis A.; Schimmerling, Walter

2000-01-01

The human exploration of Mars will impose unavoidable health risks from galactic cosmic rays (GCR) and possibly solar particle events (SPE). It is the goal of NASA's Space Radiation Health Program to develop the capability to predict health risks with significant accuracy to ensure that risks are well below acceptable levels and to allow for mitigation approaches to be effective at reasonable costs. End-to-End risk assessment is the approach being followed to understand proton and heavy ion damage at the molecular, cellular, and tissue levels in order to predict the probability of the major health risk including cancer, neurological disorders, hereditary effects, cataracts, and acute radiation sickness and to develop countermeasures for mitigating risks.

Proton beam radiotherapy of iris melanoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Damato, Bertil; Kacperek, Andrzej; Chopra, Mona

2005-09-01

Purpose: To report on outcomes after proton beam radiotherapy of iris melanoma. Methods and Materials: Between 1993 and 2004, 88 patients with iris melanoma received proton beam radiotherapy, with 53.1 Gy in 4 fractions. Results: The patients had a mean age of 52 years and a median follow-up of 2.7 years. The tumors had a median diameter of 4.3 mm, involving more than 2 clock hours of iris in 32% of patients and more than 2 hours of angle in 27%. The ciliary body was involved in 20%. Cataract was present in 13 patients before treatment and subsequently developed inmore » another 18. Cataract had a 4-year rate of 63% and by Cox analysis was related to age (p = 0.05), initial visual loss (p < 0.0001), iris involvement (p < 0.0001), and tumor thickness (p < 0.0001). Glaucoma was present before treatment in 13 patients and developed after treatment in another 3. Three eyes were enucleated, all because of recurrence, which had an actuarial 4-year rate of 3.3% (95% CI 0-8.0%). Conclusions: Proton beam radiotherapy of iris melanoma is well tolerated, the main problems being radiation-cataract, which was treatable, and preexisting glaucoma, which in several patients was difficult to control.« less

Radiation therapy of carcinoma of the maxillary antrum (in Japanese)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matsuura, S.; Taketa, C.; Ono, I.

1973-06-01

The total number of 187 cases with carcinoma of the maxillary antrum treated at National Cancer Center from 1962 to 1971 were divided into two groups. Group A (1962 to 1966) consisted of 90 cases, of which 72.2% received mainly radiotherapy with dose over 6000 rad. Group B (1967 to 1972) consisted of 97 cases, of which patients irradiated with over 6000 rad was 21.6% and intraarterial infusion of 5-FU was combined. As the injuries after irradiation, 48 cases developed radiation cataract. Advanced disturbances of visual acuity by cataract was caused by the radiation with over 4000 rad in aboutmore » two-thirds of them within 2yrs and in one third within 3to 5 yrs. In 13 patients with shielding of the eyeball from the beginning, no complications of the eyes were found except in one patient. In the injuries of the bone and the soft tissue, the fragments of the bones irradiated with high doses were easily infected and were incurable when osteomyelitis was complicated. Five cases in the over5-year survival cases showed third-degree injuries of the tissue from external irradiation with over 6000 rad. The 3-year crude survival rate of A and B group was 51.6 and 46.0% respectively, and the 5-year crude survival rate in the whole was 42.2%. Adequate combination of radiotherapy, intraarterial infusion for chemotherapy, and surgery are now under study. At present, the dose of 5-Fu was tentatively determined at 3000 mg and the radiation was 4000 rad. For the improvement of therapeutic results, programmings with plans of radiotherapy of each case and the managements of the detailed information on personal history are now under preparation as a radiotherapy using electric computer. (JA)« less

Cataracts in congenital toxoplasmosis.

PubMed

Arun, Veena; Noble, A Gwendolyn; Latkany, Paul; Troia, Robert N; Jalbrzikowski, Jessica; Kasza, Kristen; Karrison, Ted; Cezar, Simone; Sautter, Mari; Greenwald, Mark J; Mieler, William; Mets, Marilyn B; Alam, Ambereen; Boyer, Kenneth; Swisher, Charles N; Roizen, Nancy; Rabiah, Peter; Del Monte, Monte A; McLeod, Rima

2007-12-01

To determine the incidence and natural history of cataracts in children with congenital toxoplasmosis. Children referred to the National Collaborative Chicago-based Congenital Toxoplasmosis Study (NCCCTS) between 1981 and 2005 were examined by ophthalmologists at predetermined times according to a specific protocol. The clinical course and treatment of patients who developed cataracts were reviewed. In the first year of life, 134 of 173 children examined were treated with pyrimethamine, sulfadiazine, and leukovorin, while the remaining 39 were not treated. Cataracts occurred in 27 eyes of 20 patients (11.6%, 95% confidence interval [7.2%, 17.3%]). Fourteen cataracts were present at birth and 13 developed postnatally. Locations of the cataracts included anterior polar (three eyes), anterior subcapsular (six eyes), nuclear (five eyes), posterior subcapsular (seven eyes), and unknown (six eyes). Thirteen cataracts were partial, nine total, and five with unknown complexity. Twelve cataracts remained stable, 12 progressed, and progression was not known for 3. Five of 27 eyes had cataract surgery, with 2 of these developing glaucoma. Sixteen eyes of 11 patients had retinal detachment and cataract. All eyes with cataracts had additional ocular lesions. In the NCCCTS cohort, 11.6% of patients were diagnosed with cataracts. There was considerable variability in the presentation, morphology, and progression of the cataracts. Associated intraocular pathology was an important cause of morbidity.

Determining the acoustic properties of the lens using a high-frequency ultrasonic needle transducer.

PubMed

Huang, Chih-Chung; Zhou, Qifa; Ameri, Hossein; Wu, Da Wei; Sun, Lei; Wang, Shyh-Hau; Humayun, Mark S; Shung, K Kirk

2007-12-01

Ultrasonic parameters including sound velocity and attenuation coefficient have recently been found to be useful in characterizing the cataract lens noninvasively. However, the regional changes of these acoustic parameters in the lens cannot be detected directly by those ultrasonic measurements. This prompted us to fabricate a 46-MHz needle transducer (lead magnesium niobate-lead titanate [PMN-PT] single crystal) with an aperture size of 0.4 mm and a diameter of 0.9 mm for directly measuring the sound velocity and frequency-dependent attenuation coefficient in lenses. These parameters have been shown to be related to the hardness of a cataract, and hence this technique may allow surgeons to detect the acoustic properties of the cataract via a small incision on the cornea before/during phacoemulsification surgery. To verify the performance of the needle transducer, experiments were performed on porcine lenses in which two types of cataracts (nucleus and cortical) were induced artificially. The needle transducer was mounted on a positioning system and its tip was inserted into the lens, allowing the anterior-to-posterior profiles of acoustic parameters along the lens axis to be obtained immediately. The experimental results show that the acoustic parameters are not constant within a single normal lens. The sound velocity and ultrasound attenuation coefficient (at 46 MHz) were 1701.2 +/- 8.4 m/s (mean +/- SD) and 9.42 +/- 0.57 dB/mm, respectively, at the nucleus, and 1597.2 +/- 9.6, 1589.3 +/- 6.1 m/s and 0.42 +/- 0.26 and 0.40 +/- 0.33 dB/mm close to the anterior and posterior capsules, respectively. Finally, the data obtained demonstrate that regional variations in the acoustic properties of lenses corresponding to the hardness of different types of cataract can be detected sensitively by a needle transducer.

Preventive role of lens antioxidant defense mechanism against riboflavin-mediated sunlight damaging of lens crystallins.

PubMed

Anbaraki, Afrooz; Khoshaman, Kazem; Ghasemi, Younes; Yousefi, Reza

2016-10-01

The main components of sunlight reaching the eye lens are UVA and visible light exerting their photo-damaging effects indirectly by the aid of endogenous photosensitizer molecules such as riboflavin (RF). In this study, lens proteins solutions were incubated with RF and exposed to the sunlight. Then, gel mobility shift analysis and different spectroscopic assessments were applied to examine the structural damaging effects of solar radiation on these proteins. Exposure of lens proteins to direct sunlight, in the presence of RF, leads to marked structural crosslinking, oligomerization and proteolytic instability. These structural damages were also accompanied with reduction in the emission fluorescence of Trp and Tyr and appearance of a new absorption peak between 300 and 400nm which can be related to formation of new chromophores. Also, photo-oxidation of lens crystallins increases their oligomeric size distribution as examined by dynamic light scattering analysis. The above mentioned structural insults, as potential sources of sunlight-induced senile cataract and blindness, were significantly attenuated in the presence of ascorbic acid and glutathione which are two important components of lens antioxidant defense system. Therefore, the powerful antioxidant defense mechanism of eye lens is an important barrier against molecular photo-damaging effects of solar radiations during the life span. Copyright © 2016 Elsevier B.V. All rights reserved.

Which lamp will be optimum to eye? Incandescent, fluorescent or LED etc

PubMed Central

Chen, Liang; Zhang, Xiao-Wei

2014-01-01

Low frequency flicker, high frequency flicker, strong light, strong blue light, infrared, ultraviolet, electromagnetic radiation, ripple flicker and dimming flicker produced by different lamps have negative impact on vision, eyes and health. Negative impact on eyes resulting in myopia or cataract etc: the solution is to remove all the negative factors by applying upright lighting technology and that is optimum to vision, eyes and health. PMID:24634884

Which lamp will be optimum to eye? Incandescent, fluorescent or LED etc.

PubMed

Chen, Liang; Zhang, Xiao-Wei

2014-01-01

Low frequency flicker, high frequency flicker, strong light, strong blue light, infrared, ultraviolet, electromagnetic radiation, ripple flicker and dimming flicker produced by different lamps have negative impact on vision, eyes and health. Negative impact on eyes resulting in myopia or cataract etc: the solution is to remove all the negative factors by applying upright lighting technology and that is optimum to vision, eyes and health.

Cataract surgery practices in the United States Veterans Health Administration.

PubMed

Havnaer, Annika G; Greenberg, Paul B; Cockerham, Glenn C; Clark, Melissa A; Chomsky, Amy

2017-04-01

To describe current cataract surgery practices within the United States Veterans Health Administration (VHA). Veterans Health Administration hospitals in the U.S. Retrospective data analysis. An initial e-mail containing a link to an anonymous 32-question survey of cataract surgery practices was sent to participants in May 2016. Two reminder e-mails were sent to nonresponders 1 week and 2 weeks after the initial survey was sent; the remaining nonresponders were called twice over a 2-week period. The data were analyzed using descriptive statistics. The response rate was 75% (67/89). Cataract surgeons routinely ordered preoperative testing in 29 (45%) of 65 sections and preoperative consultations in 26 (39%) of 66 sections. In 22 (33%) of 66 sections, cataract surgeons administered intracameral antibiotics. In 61 (92%) of 66 sections, cataract surgeons used toric intraocular lenses (IOLs). In 20 (30%) of 66 sections, cataract surgeons used multifocal IOLs. Cataract surgeons in 6 (9%) of 66 sections performed femtosecond laser-assisted cataract surgery. In 6 (9%) of 66 sections, cataract surgeons performed immediate sequential bilateral cataract surgery. Forty-nine (74%) ophthalmology chiefs reported a high level of satisfaction with Veterans Affairs ophthalmology. The survey results indicate that in cataract surgery in the VHA, routine preoperative testing is commonly performed and emerging practices, such as femtosecond laser-assisted cataract surgery and immediate sequential bilateral cataract surgery, have limited roles. The results of this survey could benchmark future trends in U.S. cataract surgery practices, especially in teaching hospital settings. Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Correction of irregular and induced regular corneal astigmatism with toric IOL after posterior segment surgery: a case series.

PubMed

Kolozsvári, Bence L; Losonczy, Gergely; Pásztor, Dorottya; Fodor, Mariann

2017-01-13

Toric intraocular lens (IOL) implantation can be an effective method for correcting corneal astigmatism in patients with vitreoretinal diseases and cataract. Our purpose is to report the outcome of toric IOL implantation in two cases - a patient with scleral-buckle-induced regular corneal astigmatism and a patient with keratoconus following pars plana vitrectomy. As far as we are aware, there are no reported cases of toric IOL implantation in a vitrectomized eye with keratoconus nor of toric IOL implantation in patients with scleral-buckle-induced regular corneal astigmatism. Two patients with myopia and high corneal astigmatism underwent cataract operation with toric IOL implantation after posterior segment surgery. Myopia and high astigmatism (>2.5 diopter) were caused by previous scleral buckling in one case and by keratoconus in the other case. Pre- and postoperative examinations during the follow-up of included uncorrected and spectacle corrected distance visual acuity (UCDVA/CDVA), automated kerato-refractometry (Topcon), Pentacam HR, IOL Master (Zeiss) axial length measurements and fundus optical coherence tomography (Zeiss). One year postoperatively, the UCDVA and CDVA were 20/25 and 20/20 in both cases, respectively. The absolute residual refractive astigmatism was 1.0 and 0.75 Diopters, respectively. The IOL rotation was within 3° in both eyes, therefore IOL repositioning was not necessary. Complications were not observed in our cases. These cases demonstrate that toric IOL implantation is a predictable and safe method for the correction of high corneal astigmatism in complicated cases with different origins. Irregular corneal astigmatism in keratoconus or scleral-buckle-induced regular astigmatisms can be equally well corrected with the use of toric IOL during cataract surgery. Previous scleral buckling or pars plana vitrectomy seem to have no impact on the success of the toric IOL implantation, even in keratoconus. IOL rotational stability and refractive predictability in patients with a previous vitreoretinal surgery can be as good as in uncomplicated cases.

A Review of Radiation Protection Solutions for the Staff in the Cardiac Catheterisation Laboratory.

PubMed

Badawy, Mohamed Khaldoun; Deb, Pradip; Chan, Robert; Farouque, Omar

2016-10-01

Adverse health effects of radiation exposure to staff in cardiac catheterisation laboratories have been well documented in the literature. Examples include increased risk of cataracts as well as possible malignancies. These risks can be partly mitigated by reducing scatter radiation exposure to staff during diagnostic and interventional cardiac procedures. There are currently commercially available radiation protection tools, including radioprotective caps, gloves, eyewear, thyroid collars, aprons, mounted shields, table skirts and patient drapes to protect staff from excessive radiation exposure. Furthermore, real-time dose feedback could lead to procedural changes that reduce operator dose. The objective of this review is to examine the efficacy of these tools and provide practical recommendations to reduce occupational radiation exposure with the aim of minimising long-term adverse health outcomes. Copyright © 2016 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

Ku80 Counters Oxidative Stress-Induced DNA Damage and Cataract Formation in the Human Lens.

PubMed

Smith, Andrew John Oliver; Ball, Simon Sidney Robert; Manzar, Kamal; Bowater, Richard Peter; Wormstone, Ian Michael

2015-12-01

Oxidative stress in the human lens leads to a wide range of damage including DNA strand breaks, which are likely to contribute to cataract formation. The protein Ku80 is a fundamental component of the nonhomologous end-joining pathway that repairs DNA double strand breaks. This study investigates the putative impact of Ku80 in cataract prevention in the human lens. The present study used the human lens epithelial cell line FHL124 and whole human lens organ culture. Targeted siRNA was used to deplete Ku80, with Western blot and immunocytochemistry employed to assess Ku80 expression levels. Oxidative stress was induced with hydrogen peroxide and DNA strand breaks measured by alkaline comet assay and γH2AX foci counts. Visual quality of whole human lenses was measured with image analysis software. Expression of Ku80 was predominately found in the cell nucleus of both FHL124 cells and native human lens epithelium. Treatment of FHL124 cells and whole lens cultures with siRNA targeted against Ku80 resulted in a significant knockdown at the protein level. Application of oxidative stress (30 μM H2O2) created more DNA strand breaks when added to Ku80 knockdown cells than in scrambled siRNA control cells as determined by the alkaline comet assay and the number of γH2AX foci. In whole lens cultures, exposure to 1 mM H2O2 resulted in more lens opacity in Ku80 knockdown lenses than match-paired controls. Depletion of Ku80 in the lens through acute change or a consequence of aging is likely to increase levels of DNA strand breaks, which could negatively influence physiological function and promote lens opacity. It is therefore feasible that Ku80 plays a role in retarding cataract formation.

Corneal Optical Quality Following Sub 1.8 mm Micro-Incision Cataract Surgery vs. 2.2 mm Mini-Incision Coaxial Phacoemulsification

PubMed Central

Alió, Jorge L.; Elkady, Bassam; Ortiz, Dolores

2010-01-01

Purpose: To study and compare the effects of the micro-incision cataract surgery (MICS-sub 1.8 mm) and miniincision coaxial phacoemulsification (2.2 mm) on the optical quality of the cornea characterized in terms of corneal aberrations. Materials and Methods: Fifty eyes underwent MICS and 50 mini-incision phacoemulsification, by the same surgeon. Both types of cataract surgery were performed using low ultrasound power and through a clear corneal incision, placed on the steepest corneal meridian ranging from 1.6 to 1.8 in MICS (Group I) and from 2.12 to 2.3 mm in mini-incision coaxial phacoemulsification (Group II). Seidel and Zernike aberration coefficients and RMS values were obtained for a 6-mm pupil preoperatively and one month after surgery. Results: The corneal astigmatism did not show statistically significant changes in either of the two groups: (MICS: –0.73 ± 0.63, –0.65 ± 0.53 D, P = 0.25), (mini-incision phacoemulsification; –1.21 ± 1.52, –1.00 ± 1.19 D, P = 0.12). The total RMS remained unchanged after MICS (1.77 ± 1.7, 1.65 ± 1.3 μm, P = 0.18) and mini-incision phacoemulsification (2.00 ± 1.87, 2.09 ± 1.8 μm, P = 0.41). Statistically significant changes were found for coma (P = 0.004) and higher-order aberrations (P < 0.001), showing MICS significantly less changes in cornea. Conclusions: Both MICS and mini-incision phacoemulsification do not degrade the optical quality of the cornea. Both surgeries do not induce a modification of the corneal astigmatism, even in the axis. It seems that 2 mm is the limit around which no optical changes are induced by cataract surgery in the human cornea. PMID:20543945

The structural alteration and aggregation propensity of glycated lens crystallins in the presence of calcium: Importance of lens calcium homeostasis in development of diabetic cataracts

NASA Astrophysics Data System (ADS)

ZM, Sara Zafaranchi; Khoshaman, Kazem; Masoudi, Raheleh; Hemmateenejad, Bahram; Yousefi, Reza

2017-01-01

The imbalance of the calcium homeostasis in the lenticular tissues of diabetic patients is an important risk factor for development of cataract diseases. In the current study, the impact of elevated levels of calcium ions were investigated on structure and aggregation propensity of glycated lens crystallins using gel electrophoresis and spectroscopic assessments. The glycated proteins indicated significant resistance against calcium-induced structural insults and aggregation. While, glycated crystallins revealed an increased conformational stability; a slight instability was observed for these proteins upon interaction with calcium ions. Also, in the presence of calcium, the proteolytic pattern of native crystallins was altered and that of glycated protein counterparts remained almost unchanged. According to results of this study it is suggested that the structural alteration of lens crystallins upon glycation may significantly reduce their calcium buffering capacity in eye lenses. Therefore, under chronic hyperglycemia accumulation of this cataractogenic metal ion in the lenticular tissues may subsequently culminate in activation of different pathogenic pathways, leading to development of lens opacity and cataract diseases.

Aldose reductase inhibitory, anti-cataract and antioxidant potential of selected medicinal plants from the Marathwada region, India.

PubMed

Gacche, R N; Dhole, N A

2011-04-01

The water, ethanol and chloroform extracts of selected plants such as Adhatoda vasica (L.) (Acanthaceae), Caesalpinia bonduc (L.), Cassia fistula (L.) (Caesalpiniaceae) and Biophytum sensitivum (L.) (Oxalidaceae) were evaluated for rat lens aldose reductase inhibitory (RLAR) potential, anti-cataract and antioxidant activities. All the samples inhibited the aldose reductase considerably and exhibited anti-cataract activity, while C. fistula (IC(50), 0.154 mg mL(-1)) showed significant RLAR inhibitory activity as compared to the other tested samples, and was further found to be more effective in maintaining sugar-induced lens opacity in the rat lens model. The antioxidant potential of plant extracts was determined using DPPH (2,2-diphenyl-1-picryl hydrazine), hydroxyl (OH), nitric oxide (NO) and hydrogen peroxide (H(2)O(2)) scavenging activities, along with determination of reducing power, ferrous ion chelating ability and inhibition of polyphenol oxidase (PPO). The extracts of the tested plant showed significant free radical scavenging activities and inhibited the activity of enzyme PPO, a model oxidising enzyme. The plant samples were found to possess considerable amounts of vitamin C, total polyphenols and flavonoids.

Towards a Better Understanding of the Effects of UV on Atlantic Walruses, Odobenus rosmarus rosmarus: A Study Combining Histological Data with Local Ecological Knowledge.

PubMed

Martinez-Levasseur, Laura M; Furgal, Chris M; Hammill, Mike O; Burness, Gary

2016-01-01

Walruses, Odobenus rosmarus, play a key role in the Arctic ecosystem, including northern Indigenous communities, which are reliant upon walruses for aspects of their diet and culture. However, walruses face varied environmental threats including rising sea-water temperatures and decreasing ice cover. An underappreciated threat may be the large amount of solar ultraviolet radiation (UV) that continues to reach the Arctic as a result of ozone loss. UV has been shown to negatively affect whales. Like whales, walrus skin is unprotected by fur, but in contrast, walruses spend long periods of time hauled-out on land. In this study, we combined the results of histological analyses of skin sections from five Atlantic walruses, Odobenus rosmarus rosmarus, collected in Nunavik (Northern Quebec, Canada) with qualitative data obtained through the interviews of 33 local walrus hunters and Inuit Elders. Histological analyses allowed us to explore UV-induced cellular lesions and interviews with experienced walrus hunters and Elders helped us to study the incidences and temporal changes of UV-induced gross lesions in walruses. At the microscopic scale, we detected a range of skin abnormalities consistent with UV damage. However, currently such UV effects do not seem to be widely observed at the whole-animal level (i.e., absence of skin blistering, erythema, eye cataract) by individuals interviewed. Although walruses may experience skin damage under normal everyday UV exposure, the long-term data from local walrus hunters and Inuit Elders did not report a relation between the increased sun radiation secondary to ozone loss and walrus health.

Femtosecond laser-assisted compared with standard cataract surgery for removal of advanced cataracts.

PubMed

Hatch, Kathryn M; Schultz, Tim; Talamo, Jonathan H; Dick, H Burkhard

2015-09-01

To compare effective phacoemulsification time (EPT) for the removal of brunescent cataracts treated with femtosecond laser-assisted cataract surgery with standard cataract phacoemulsification techniques. Ruhr University Eye Hospital, Bochum, Germany. Comparative prospective case study. The Lens Opacities Classification System III (LOCS III) grading system was used to measure eyes divided into 4 groups having cataract surgery. Groups 1 and 2 contained eyes with LOCS III grade nuclear opalescence (NO) 3 cataracts treated with standard cataract surgery and femtosecond laser-assisted cataract surgery, respectively. Groups 3 and 4 contained brunescent cataracts, LOCS III grades NO5, treated with standard cataract surgery and femtosecond laser-assisted cataract surgery, respectively. There were 240 eyes, with 60 eyes in each group. The EPT in Group 1 ranged from 0.46 to 3.10 (mean 1.38); the EPT in all eyes in Group 2 was 0 (P < .001). The EPT in Groups 3 and 4 was 2.12 to 19.29 (mean 6.85) and 0 to 6.75 (mean 1.35), respectively (P < .001). A comparison between EPT in Groups 1 and 4 showed that EPT in Group 4 was also lower than in Group 1 (P = .013). Groups 4 and 1 were the most statistically similar of all groups compared, suggesting that EPT for a femtosecond laser-treated grade 5 cataract was most similar to that of a standard-treated grade 3 cataract. Femtosecond laser pretreatment for brunescent cataracts allowed for a significant reduction in EPT compared with manual standard phacoemulsification techniques. Drs. Hatch, Talamo, and Dick are consultants to Abbott Medical Optics, Inc. Dr. Schultz has no financial or proprietary interest in any material or method mentioned. Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Cataract prevalence varies substantially with assessment systems: comparison of clinical and photographic grading in a population-based study.

PubMed

Tan, Anna C S; Wang, Jie Jin; Lamoureux, Ecosse L; Wong, Wanling; Mitchell, Paul; Li, Jialiang; Tan, Ava Grace; Wong, Tien Y

2011-08-01

Cataract is the major cause of blindness worldwide yet there is no consensus on its assessment and definition. This study compares age-related cataract prevalence derived from two commonly used methods: clinical assessment using the Lens Opacity Classification System (LOCS III) and photographic grading using the Wisconsin Cataract Grading System (Wisconsin System). The Singapore Malay Eye Study is a population-based study of 3,280 Singapore Malays aged 40-80 years. Presence of nuclear, cortical and posterior sub-capsular cataract was assessed clinically during slit-lamp examination using LOCS III, and via slit-lamp and retro-illumination photographic grading using the Wisconsin System. Analyses were conducted to determine agreement in cataract prevalence estimates between the two grading Systems and approaches. Poor agreement was found between severity levels of the two grading scales for all three cataract types. Using currently accepted cut-offs to define nuclear (≥ 4 on both LOCS III and Wisconsin System), cortical (≥ 2 in LOCS III, ≥ 25% in Wisconsin) and PSC (≥ 2 in LOCS III, ≥ 5 % in Wisconsin) cataract, the LOCS III overestimated the prevalence of significant cataract as compared to the Wisconsin System, with nuclear cataract prevalence, 27.5% (LOCS III) versus 17.0% (Wisconsin System), cortical cataract prevalence, 27.9% versus 7.0% and posterior sub-capsular cataract prevalence, 7.8% versus 5.1%. The prevalence of cataract in a population varies substantially by measurement methods, with systematically different estimates found using the two most frequent cataract grading systems. This study re-emphasizes the need for global standards to assess and define cataract for epidemiologic and clinical studies.

Smoking, socioeconomic factors, and age-related cataract: The Singapore Malay Eye study.

PubMed

Wu, Renyi; Wang, Jie Jin; Mitchell, Paul; Lamoureux, Ecosse L; Zheng, Yingfeng; Rochtchina, Elena; Tan, Ava G; Wong, Tien Yin

2010-08-01

To describe the relationship of smoking, sex, and socioeconomic factors with age-related cataract in Malay adults in Singapore. In a population-based study, 3280 Malay individuals aged 40 to 80 years participated (78.7% response rate). All had interviews, systemic examination, and laboratory investigations. Lens opacity was graded from slitlamp and retroillumination photographs using the Wisconsin Cataract Grading System. Smoking-cataract associations were compared with the Blue Mountains Eye Study in Australia. Of 2927 participants (89.2%) with gradable lens photographs, 1338 (45.7%) had cataract. After adjusting for age, sex, body mass index, hypertension, and diabetes, current smokers had a higher prevalence of nuclear cataract (odds ratio [OR], 2.06; 95% confidence interval [CI], 1.46-2.98), cortical cataract (OR, 1.33; 95% CI, 1.02-1.74), posterior subcapsular cataract (OR, 1.39; 95% CI, 1.02-1.91), or any cataract (OR, 1.48; 95% CI, 1.10-1.99). These associations were not seen in the Blue Mountains Eye Study. Primary or lower education (OR, 1.67; 95% CI, 1.06-2.64) and low monthly income (OR, 1.43; 95% CI, 1.09-1.87) were both associated with nuclear cataract, while small-sized public housing was associated with posterior subcapsular cataract (OR, 1.70; 95% CI, 1.28-2.25). Among men, 43.5% currently smoked compared with only 3.2% of women. The population attributable risk of nuclear cataract due to smoking was estimated to be 17.6% in men. Smoking and indicators of low socioeconomic status were associated with cataract in Malay persons, with 1 in 6 nuclear cataract cases in men attributable to smoking. Smoking-cataract associations were stronger in Malay than in white persons.

Cat-Map: putting cataract on the map

PubMed Central

Bennett, Thomas M.; Hejtmancik, J. Fielding

2010-01-01

Lens opacities, or cataract(s), may be inherited as a classic Mendelian disorder usually with early-onset or, more commonly, acquired with age as a multi-factorial or complex trait. Many genetic forms of cataract have been described in mice and other animal models. Considerable progress has been made in mapping and identifying the genes and mutations responsible for inherited forms of cataract, and genetic determinants of age-related cataract are beginning to be discovered. To provide a convenient and accurate summary of current information focused on the increasing genetic complexity of Mendelian and age-related cataract we have created an online chromosome map and reference database for cataract in humans and mice (Cat-Map). PMID:21042563

Cataract surgery among Medicare beneficiaries.

PubMed

Schein, Oliver D; Cassard, Sandra D; Tielsch, James M; Gower, Emily W

2012-10-01

To present descriptive epidemiology of cataract surgery among Medicare recipients in the United States. Cataract surgery performed on Medicare beneficiaries in 2003 and 2004. Medicare claims data were used to identify all cataract surgery claims for procedures performed in the United States in 2003-2004. Standard assumptions were used to limit the claims to actual cataract surgery procedures performed. Summary statistics were created to determine the number of procedures performed for each outcome of interest: cataract surgery rates by age, sex, race and state; surgical volume by facility type and surgeon characteristics; time interval between first- and second-eye cataract surgery. The national cataract surgery rate for 2003-2004 was 61.8 per 1000 Medicare beneficiary person-years. The rate was significantly higher for females and for those aged 75-84 years. After adjustment for age and sex, blacks had approximately a 30% lower rate of surgery than whites. While only 5% of cataract surgeons performed more than 500 cataract surgeries annually, these surgeons performed 26% of the total cataract surgeries. Increasing surgical volume was found to be highly correlated with use of ambulatory surgical centers and reduced time interval between first- and second-eye surgery in the same patient. The epidemiology of cataract surgery in the United States Medicare population documents substantial variation in surgical rates by race, sex, age, and by certain provider characteristics.

Elimination of avoidable blindness due to cataract: Where do we prioritize and how should we monitor this decade?

PubMed Central

Murthy, Gudlavalleti V S; John, Neena; Shamanna, Bindiganavale R; Pant, Hira B

2012-01-01

Background: In the final push toward the elimination of avoidable blindness, cataract occupies a position of eminence for the success of the Right to Sight initiative. Aims: Review existing situation and assess what monitoring indicators may be useful to chart progress towards attaining the goals of Vision 2020. Settings and Design: Review of published papers from low and middle income countries since 2000. Materials and Methods: Published population-based data on prevalence of cataract blindness/visual impairment were accessed and prevalence of cataract blindness/visual impairment computed, where not reported. Data on prevalence of cataract blindness, cataract surgical coverage at different visual acuity cut offs, surgical outcomes, and prevalence of cataract surgery were analyzed. Scatter plots were used to look at relationships of some variables, with Human Development Index (HDI) rank. Available data on Cataract Surgical Rate (CSR) was plotted against prevalence of cataract surgery reported from surveys. Results: Worse HDI Ranks were associated with higher prevalence of cataract blindness. Most studies showed that a significant proportion of the blind were covered by surgery, while a fifth showed that a significant proportion, were operated before they went blind. A good visual outcome after surgery was positively correlated with higher surgical coverage. CSR was positively correlated with cataract surgical coverage. Conclusions: Cataract surgical coverage is increasing in most countries at vision <3/60 and visual outcomes after cataract surgery are improving. Establishing population-based surveillance of cataract surgical need and performance is a strong monitoring tool and will help program planners immensely. PMID:22944756

First and second eye cataract surgery and driver self-regulation among older drivers with bilateral cataract: a prospective cohort study.

PubMed

Agramunt, Seraina; Meuleners, Lynn B; Fraser, Michelle L; Chow, Kyle C; Ng, Jonathon Q; Raja, Vignesh

2018-02-17

Driving a car is the most common form of transport among the older population. Common medical conditions such as cataract, increase with age and impact on the ability to drive. To compensate for visual decline, some cataract patients may self-regulate their driving while waiting for cataract surgery. However, little is known about the self-regulation practices of older drivers throughout the cataract surgery process. The aim of this study is to assess the impact of first and second eye cataract surgery on driver self-regulation practices, and to determine which objective measures of vision are associated with driver self-regulation. Fifty-five older drivers with bilateral cataract aged 55+ years were assessed using the self-reported Driving Habits Questionnaire, the Mini-Mental State Examination and three objective visual measures in the month before cataract surgery, at least one to three months after first eye cataract surgery and at least one month after second eye cataract surgery. Participants' natural driving behaviour in four driving situations was also examined for one week using an in-vehicle monitoring device. Two separate Generalised Estimating Equation logistic models were undertaken to assess the impact of first and second eye cataract surgery on driver-self-regulation status and which changes in visual measures were associated with driver self-regulation status. The odds of being a self-regulator in at least one driving situation significantly decreased by 70% after first eye cataract surgery (OR: 0.3, 95% CI: 0.1-0.7) and by 90% after second eye surgery (OR: 0.1, 95% CI: 0.1-0.4), compared to before first eye surgery. Improvement in contrast sensitivity after cataract surgery was significantly associated with decreased odds of self-regulation (OR: 0.02, 95% CI: 0.01-0.4). The findings provide a strong rationale for providing timely first and second eye cataract surgery for older drivers with bilateral cataract, in order to improve their mobility and independence.

Risk of Cataract among Subjects with the Acquired Immune Deficiency Syndrome Free of Ocular Opportunistic Infections

PubMed Central

Kempen, John H.; Sugar, Elizabeth A.; Varma, Rohit; Dunn, James P.; Heinemann, Murk-Hein; Jabs, Douglas A.; Lyon, Alice T.; Lewis, Richard A.

2014-01-01

Purpose To evaluate the risk of cataract in the setting of AIDS. Design Prospective cohort study. Participants Subjects with AIDS free of ocular opportunistic infections throughout catamnesis. Methods During 1998–2008 inclusive, subjects ≥13 years of age were enrolled. Demographic characteristics and clinical characteristics were documented at enrollment and semiannually. Main Outcome Measures Cataract was defined as high-grade lens opacity observed by biomicroscopy and judged to be the cause of a best-corrected visual acuity worse than 20/40. Eyes that underwent cataract surgery during follow-up were considered to have developed cataract prior to the first visit when pseudophakia or aphakia was observed. Results Among 1,606 participants (3,212 eyes), at enrollment 1.9% (95% confidence interval (CI): 1.3%−2.7%) were observed to have cataract or prior cataract surgery. Among the 2,812 eyes initially free of cataract, and followed longitudinally (median follow-up=4.6 years), the incidence of cataract was 0.37%/eye-year (95% CI: 0.26%– 0.53%). In addition to age, significant cataract risk factors included prior cataract in the contralateral eye (adjusted hazard ratio (aHR)=21.6, 95% CI: 10.4–44.8), anterior segment inflammation (aHR=4.40, 95% CI: 1.64–11.9), prior retinal detachment (aHR=4.94, 95% CI: 2.21–11.0), and vitreous inflammation (aHR=7.12, 95% CI: 2.02– 25.0), each studied as a time-updated characteristic. Detectable HIV RNA in peripheral blood was associated with lower risk of cataract at enrollment (adjusted odds ratio=0.32, 95% CI: 0.12–0.80) but not of incident cataract (aHR=1.58, 95% CI: 0.90–2.76). After adjustment for other factors, neither the then current absolute CD4+ T cell count nor antiretroviral therapy status showed consistent association with cataract risk, nor did an additive diagnosis of other other co-morbidities. Compared to the available population-based studies that used similar definitions of cataract, the age-specific prevalence of cataract in our cohort was higher than in one of two such studies, and the age-specific incidence of cataract surgery was higher. Conclusions Our results suggest cataract may occur earlier among patients with AIDS free of ocular opportunistic infections than in the general population. Cataract risk was associated most strongly with age and with other ocular morbidity in this population. With improved survival, the burden of cataract likely will increase for persons with HIV/AIDS. PMID:25109932

Saving Your Students' Skin. Undergraduate Experiments that Probe UV Protection by Sunscreens and Sunglasses

NASA Astrophysics Data System (ADS)

Abney, James R.; Scalettar, Bethe A.

1998-06-01

Recent scientific evidence suggests that chlorofluorocarbons have substantially depleted the ozone layer, the earth's primary filter for ultraviolet radiation. At the same time, medical evidence has accumulated which suggests that exposure to ultraviolet radiation is a major cause of prevalent human health disorders, including skin cancer and cataracts. For these reasons, consumer purchases of sunscreens and sunglasses, which provide protection from ultraviolet radiation, have soared, and manufacturer interest in improving these products has intensified. This article describes absorption spectroscopy experiments that illustrate the mechanism of action of sunscreens and sunglasses and that highlight the differences between different products. The experiments are well suited to incorporation into an undergraduate science laboratory and will expose students to absorption phenomena in a familiar context with substantial environmental and medical relevance.

The first cataract surgeons in Latin America: 1611–1830

PubMed Central

Leffler, Christopher T; Wainsztein, Ricardo D

2016-01-01

We strove to identify the earliest cataract surgeons in Latin America. Probably by 1611, the Genovese oculist Francisco Drago was couching cataracts in Mexico City. The surgeon Melchor Vásquez de Valenzuela probably performed cataract couching in Lima by 1697. Juan Peré of France demonstrated cataract couching in Veracruz and Mexico City between 1779 and 1784. Juan Ablanedo of Spain performed couching in Veracruz in 1791. Cataract extraction might have been performed in Havana and Caracas by 1793 and in Mexico by 1797. The earliest contemporaneously documented cataract extractions in Latin America were performed in Guatemala City by Narciso Esparragosa in 1797. In addition to Esparragosa, surgeons born in the New World who established the academic teaching of cataract surgery included José Miguel Muñoz in Mexico and José María Vargas in Caracas. Although cataract surgery came quite early to Latin America, its availability was initially inconsistent and limited. PMID:27143845

Evaluation of antioxidants and argpyrimidine in normal and cataractous lenses in north Indian population

PubMed Central

Mynampati, Bharani K; Ghosh, Sujata; Muthukumarappa, Thungapathra; Ram, Jagat

2017-01-01

AIM To assess the level of glutathione, thioltransferase, and argpyrimidine in nuclear and cortical cataractous lenses as well as in the clear lenses in the north Indian population. METHODS Human cataractous lenses were collected from the patients who underwent extracapsular cataract extraction surgery; clear lenses were collected from the freshly donated eye bank eyes. Antioxidant molecules such as glutathione and thioltransferase enzyme activity were measured; simultaneously in these lenses a blue fluorophore argpyrimidine, an advanced glycation end (AGE) product level was assessed using high performance liquid chromatography (HPLC). RESULTS The protein concentration was found to be present at higher levels in the control lenses compared to cataract lenses. A significant decrease in the glutathione level was observed in the nuclear cataractous lenses compared to cortical cataractous (P=0.004) and clear lenses (P≤0.005), but no significant change in the level of antioxidant enzyme thioltransferase was observed. Further, argpyrimidine a blue fluorophore (AGE) was found to be significantly higher in the nuclear cataract (P=0.013) compared to cortical cataract lenses. CONCLUSION Antioxidants such as glutathione significantly decrease in age-related nuclear and cortical cataract and an AGE, argpyrimidine are present at significantly higher levels in nuclear cataract. PMID:28730112

Differential cataract blindness by sex in India: Evidence from two large national surveys.

PubMed

Pant, Hira B; Bandyopadhyay, Souvik; John, Neena; Chandran, Anil; Gudlavalleti, Murthy Venkata S

2017-02-01

Women suffer disproportionately more from cataract blindness compared to males in low- and middle-income countries. Two large population-based surveys have been undertaken in India at an interval of 7 years and data from these surveys provided an opportunity to assess the trends in gender differentials in cataract blindness. Data were extracted from the surveys to discern sex differences in cataract blindness. Multivariate analysis was performed to adjust for confounders and their impact on gender differences in cataract blindness. Blindness was defined as presenting vision <20/400 in the better eye, and a cataract blind person was defined as a blind person where the principal cause of loss of vision was cataract. Prevalence of cataract blindness was higher in females compared to males in both surveys. The odds of cataract blindness for females did not change over time as observed in the surveys (1999-2001 and 2006-2007). Adjusted odds ratio from logistic regression analysis revealed that females continued to be at a higher risk of cataract blindness. Sex differences continued in India in relation to cataract blindness despite the gains made by the national program.

Biological Applications and Effects of Optical Masers.

DTIC Science & Technology

1984-06-01

term ocular effects of optical radiation on aging and macular degeneration is discussed and a final draft of the report of the Working Group assessing...exposure to short wavelength light on aging and degeneration of the retina and lens leading to degenerative maculopathies and senile cataract. Dr. Ham...chaired the Working Group assigned the task of assessing light damage to the RPE and its possible relationship to aging and macular degeneration of the

Geometrical gradients in the distribution of temperature and absorbed ultraviolet radiation in ocular tissues.

PubMed

Sliney, David H

2002-01-01

The geographical variations in the incidence of age-related ocular changes such as presbyopia and cataracts and diseases such as pterygium and droplet keratopathies have led to theories pointing to sunlight, ultraviolet radiation (UVR) exposure and ambient temperature as potential etiological factors. Some epidemiological evidence also points to an association of age-related macular degeneration to sunlight exposure. The actual distribution of sunlight exposure and the determination of temperature variations of different tissues within the anterior segment of the eye are difficult to assess. Of greatest importance are the geometrical factors that influence selective UVR exposures to different segments of the lens, cornea and retina. Studies show that the temperature of the lens and cornea varies by several degrees depending upon climate, and that the incidence of nuclear cataract incidence is greater in areas of higher ambient temperature (i.e., in the tropics). Likewise, sunlight exposure to local areas of the cornea, lens and retina varies greatly in different environments. However, epidemiological studies of the influence of environmental UVR in the development of cataract, pterygium, droplet keratopathies and age-related macular degeneration have produced surprisingly inconsistent findings. The lack of consistent results is seen to be due largely to either incomplete or erroneous estimates of outdoor UV exposure dose. Geometrical factors dominate the determination of UVR exposure of the eye. The degree of lid opening limits ocular exposure to rays entering at angles near the horizon. Clouds redistribute overhead UVR to the horizon sky. Mountains, trees and building shield the eye from direct sky exposure. Most ground surfaces reflect little UVR. The result is that highest UVR exposure occurs during light overcast where the horizon is visible and ground surface reflection is high. By contrast, exposure in a high mountain valley (lower ambient temperature) with green foliage results in a much lower ocular dose. Other findings of these studies show that retinal exposure to light and UVR in daylight occurs largely in the superior retina.

Inverse association of vitamin C with cataract in older people in India.

PubMed

Ravindran, Ravilla D; Vashist, Praveen; Gupta, Sanjeev K; Young, Ian S; Maraini, Giovanni; Camparini, Monica; Jayanthi, R; John, Neena; Fitzpatrick, Kathryn E; Chakravarthy, Usha; Ravilla, Thulasiraj D; Fletcher, Astrid E

2011-10-01

To examine the association between vitamin C and cataract in the Indian setting. Population-based cross-sectional analytic study. A total of 5638 people aged ≥60 years. Enumeration of randomly sampled villages in 2 areas of north and south India to identify people aged ≥60 years. Participants were interviewed for socioeconomic and lifestyle factors (tobacco, alcohol, household cooking fuel, work, and diet); attended a clinical examination, including lens photography; and provided a blood sample for antioxidant analysis. Plasma vitamin C was measured using an enzyme-based assay in plasma stabilized with metaphosphoric acid, and other antioxidants were measured by reverse-phase high-pressure liquid chromatography. Cataract and type of cataract were graded from digital lens images using the Lens Opacity Classification System III (LOCS III), and cataract was classified from the grade in the worse eye of ≥4 for nuclear cataract, ≥3 for cortical cataract, and ≥2 for posterior subcapsular cataract (PSC). Any cataract was defined as any unoperated or operated cataract. Of 7518 enumerated people, 5638 (75%) provided data on vitamin C, antioxidants, and potential confounders. Vitamin C was inversely associated with cataract (adjusted odds ratio [OR] for highest to lowest quartile = 0.61; 95% confidence interval (CI), 0.51-0.74; P=1.1×10(-6)). Inclusion of other antioxidants in the model (lutein, zeaxanthin, retinol, β-carotene, and α-tocopherol) made only a small attenuation to the result (OR 0.68; 95% CI, 0.57-0.82; P < 0.0001). Similar results were seen with vitamin C by type of cataract: nuclear cataract (adjusted OR 0.66; CI, 0.54-0.80; P < 0.0001), cortical cataract (adjusted OR 0.70; CI, 0.54-0.90; P < 0.002), and PSC (adjusted OR 0.58; CI, 0.45-0.74; P < 0.00003). Lutein, zeaxanthin, and retinol were significantly inversely associated with cataract, but the associations were weaker and not consistently observed by type of cataract. Inverse associations were also observed for dietary vitamin C and cataract. We found a strong association with vitamin C and cataract in a vitamin C-depleted population. The author(s) have no proprietary or commercial interest in any materials discussed in this article. Copyright © 2011 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Relationship between socioeconomic and lifestyle factors and cataracts in Koreans: the Korea National Health and Nutrition Examination Survey 2008-2011.

PubMed

Nam, G E; Han, K; Ha, S G; Han, B-D; Kim, D H; Kim, Y-H; Cho, K H; Park, Y G; Ko, B-J

2015-07-01

Cataracts are the leading cause of visual impairment and blindness, and therefore early identification and modification of the risk factors for cataracts are meaningful. This study aimed to investigate the relationship between socioeconomic status (SES) and lifestyle factors, and age-related cataracts in South Korea. This cross-sectional study was based on data collected in the 2008-2011 Korea National Health and Nutrition Examination Survey. A total of 15 866 subjects, aged ≥40 years, were included. SES was defined using household income and education level. Sociodemographic, lifestyle, and other associated factors were assessed by health interviews and examinations. Cataracts were diagnosed via slit-lamp examination using the Lens Opacities Classification System III. The prevalence of any cataract was 38.9% in men and 42.3% in women (P<0.001). In women, the risk of cataracts increased with decreases in household income (P-value for trend=0.016 and 0.041 in any, and cortical cataract, respectively) and education level (P-value for trend=0.009, 0.027, and 0.016 in any, nuclear, and cortical cataract, respectively) after adjusting for confounding factors. Current smoking was correlated with nuclear cataracts in men (OR 1.21; 95% CI: 1.00, 1.46 in age-adjusted analysis) and cataract surgery in women (OR 2.25; 95% CI: 1.00, 5.04 in multivariate-adjusted analysis). Socioeconomic disparities in cataract prevalence were observed in women; current smoking increased the risk of nuclear cataracts in men and surgery in women. Public health interventions focusing on gender differences are warranted to prevent and treat cataracts.

Cataract Surgery among Medicare Beneficiaries

PubMed Central

Schein, Oliver D.; Cassard, Sandra D.; Tielsch, James M.; Gower, Emily W.

2014-01-01

Purpose To present descriptive epidemiology of cataract surgery among Medicare recipients in the United States. Setting Cataract surgery performed on Medicare beneficiaries in 2003 and 2004. Methods Medicare claims data were used to identify all cataract surgery claims for procedures performed in the United States in 2003-2004. Standard assumptions were used to limit the claims to actual cataract surgery procedures performed. Summary statistics were created to determine the number of procedures performed for each outcome of interest: cataract surgery rates by age, race, and gender; surgical volume by facility type, surgeon characteristics, and state; time interval between first- and second-eye cataract surgery. Results The national cataract surgery rate for 2003-2004 was 61.8 per 1000 Medicare beneficiary person-years. The rate was significantly higher for females and for those 75-84. After adjustment for age and gender, blacks had approximately a 30% lower rate of surgery than whites. While only 5% of cataract surgeons performed more than 500 cataract surgeries annually, these surgeons performed 26% of the total cataract surgeries. Increasing surgical volume was found to be highly correlated with use of ambulatory surgical centers and reduced time interval between first- and second-eye surgery in the same patient. Conclusions The epidemiology of cataract surgery in the United States Medicare population documents substantial variation in surgical rates by race, gender, age, and by certain provider characteristics. PMID:22978526

Identification of cataract and post-cataract surgery optical images using artificial intelligence techniques.

PubMed

Acharya, Rajendra Udyavara; Yu, Wenwei; Zhu, Kuanyi; Nayak, Jagadish; Lim, Teik-Cheng; Chan, Joey Yiptong

2010-08-01

Human eyes are most sophisticated organ, with perfect and interrelated subsystems such as retina, pupil, iris, cornea, lens and optic nerve. The eye disorder such as cataract is a major health problem in the old age. Cataract is formed by clouding of lens, which is painless and developed slowly over a long period. Cataract will slowly diminish the vision leading to the blindness. At an average age of 65, it is most common and one third of the people of this age in world have cataract in one or both the eyes. A system for detection of the cataract and to test for the efficacy of the post-cataract surgery using optical images is proposed using artificial intelligence techniques. Images processing and Fuzzy K-means clustering algorithm is applied on the raw optical images to detect the features specific to three classes to be classified. Then the backpropagation algorithm (BPA) was used for the classification. In this work, we have used 140 optical image belonging to the three classes. The ANN classifier showed an average rate of 93.3% in detecting normal, cataract and post cataract optical images. The system proposed exhibited 98% sensitivity and 100% specificity, which indicates that the results are clinically significant. This system can also be used to test the efficacy of the cataract operation by testing the post-cataract surgery optical images.

The global state of cataract blindness.

PubMed

Lee, Cameron M; Afshari, Natalie A

2017-01-01

Cataracts are a significant cause of blindness and visual impairment worldwide. The present article reviews the literature and describes the current extent of cataracts globally, barriers to treatment, and recommendations for improving the treatment of cataracts. Prevalence and absolute number of blind because of cataracts remain high, although rates are declining in many areas globally. The age-standardized prevalence of blindness in adults older than 50 remains highest in western sub-Saharan Africa, with a rate of 6.0%. The greatest declines in age-standardized blindness because of cataracts in adults older than 50 between 1990 and 2010 were in East Asia, tropical Latin America, and western Europe. Recent studies have largely found higher rates of cataracts in women than in men. A new simulator for training ophthalmologists in manual small-incision cataract surgery holds promise for the future. The rates of cataract surgery are increasing and postoperative outcomes are improving worldwide, yet challenges to reducing the cataract burden further remain. Cost, an insufficient number of ophthalmologists, and low government funding remain significant barriers but investment in further eye care infrastructure and training of additional ophthalmologists would improve the current situation.

Different alpha crystallin expression in human age-related and congenital cataract lens epithelium.

PubMed

Yang, Jing; Zhou, Sheng; Guo, Minfei; Li, Yuting; Gu, Jianjun

2016-05-28

The purpose of this study was to investigate the different expressions of αA-crystallin and αB-crystallin in human lens epithelium of age-related and congenital cataracts. The central part of the human anterior lens capsule approximately 5 mm in diameter together with the adhering epithelial cells, were harvested and processed within 6 hours after cataract surgery from age-related and congenital cataract patients or from normal eyes of fresh cadavers. The mRNA and soluble protein levels of αA-crystallin and αB-crystallin in the human lens epithelium were detected by real-time PCR and western blots, respectively. The mRNA and soluble protein expressions of αA-crystallin and αB-crystallin in the lens epithelium were both reduced in age-related and congenital cataract groups when compared with the normal control group. However, the degree of α-crystallin loss in the lens epithelium was highly correlated with different cataract types. The α-crystallin expression of the lens epithelium was greatly reduced in the congenital cataract group but only moderately decreased in the age-related cataract group. The reduction of αA-crystallin soluble protein levels in the congenital cataract group was approximately 2.4 fold decrease compared with that of the age-related cataract group, while an mRNA fold change of 1.67 decrease was observed for the age-related cataract group. Similarly, the reduction of soluble protein levels of αB-crystallin in the congenital cataract group was approximately a 1.57 fold change compared with that of the age-related cataract group. A 1.75 fold change for mRNA levels compared with that of the age-related cataract group was observed. The results suggest that the differential loss of α-crystallin in the human lens epithelium could be associated with the different mechanisms of cataractogenesis in age-related versus congenital cataracts, subsequently resulting in different clinical presentations.

Serum 25-hydroxyvitamin D and Age-Related Cataract.

PubMed

Park, Sangshin; Choi, Nam-Kyong

2017-10-01

Cataract and insufficient vitamin D intake are both increasing worldwide concerns, yet little is known about the relationship between serum 25-hydroxyvitamin D (25(OH)D) levels and age-related cataract. We performed this study to determine the association between serum 25(OH)D levels and age-related cataract in adults. Study participants comprised 16,086 adults aged 40 years or older who had never been diagnosed with or undergone surgery for cataract using Korean National Health and Nutrition Examination Survey data from 2008 to 2012. Participants were assessed to have cataract when diagnosed with cortical, nuclear, anterior subcapsular, posterior subcapsular, or mixed cataract. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to evaluate the magnitude and significance of the association between serum 25(OH)D levels and cataract in multivariable logistic regression models. The OR for nuclear cataract with the highest quintile of serum 25(OH)D levels was 0.86 (95% CI 0.75-0.99) compared to the lowest quintile. A linear trend across quintiles was significant. Natural log-transformed serum 25(OH)D levels were also significantly associated with nuclear cataract (OR 0.84, 95% CI 0.75-0.95). The opulation-attributable fraction of nuclear cataract due to serum 25(OH)D insufficiency (<30 ng/mL) was 8.8% (p = 0.048). Serum 25(OH)D levels were inversely associated with the risk of nuclear cataract. Prospective studies investigating the effects of serum 25(OH)D levels on the development of nuclear cataract are needed to confirm our findings.

Computational Design of Epoxy/ Boron Carbide Nanocomposites for Radiation Shielding Applications

NASA Astrophysics Data System (ADS)

Bejagam, Karteek; Galehdari, Nasim; Espinosa, Ingrid; Deshmukh, Sanket A.; Kelkar, Ajit D.

An individual working in industries that include nuclear power plants, healthcare industry, and aerospace are knowingly or unknowingly exposed to radiations of different energies. Exposure to high-energy radiations such as α/ β particle emissions or gamma ray electromagnetic radiations enhances the health risks that can lead to carcinogenesis, cardiac problems, cataracts, and other acute radiation syndromes. The best possible solution to protect one from the exposure to radiations is shielding. In the present study, we have developed a new algorithm to generate a range of different structures of Diglycidyl Ether of Bisphenol F (EPON 862) and curing agent Diethylene Toluene Diamine (DETDA) resins with varying degrees of crosslinking. 3, 5, and 10 weight percent boron carbide was employed as filling materials to study its influence on the thermal and mechanical properties of composite. We further conduct the reactive molecular dynamics (RMD) simulations to investigate the effect of radiation exposure on the structural, physical, and mechanical properties of these Epoxy/Boron Carbide nanocomposites. Where possible the simulation results were compared with the experimental data.

Molecular Genetics of Cataract

PubMed Central

Shiels, Alan; Hejtmancik, J. Fielding

2017-01-01

Lens opacities or cataract(s) represent a universally important cause of visual impairment and blindness. Typically, cataract is acquired with aging as a complex disorder involving environmental and genetic risk factors. Cataract may also be inherited with an early onset either in association with other ocular and/or systemic abnormalities or as an isolated lens phenotype. Here we briefly review recent advances in gene discovery for inherited and age-related forms of cataract that are providing new insights into lens development and aging. PMID:26310156

Induction and repair of DNA strand breaks in bovine lens epithelial cells after high LET irradiation

NASA Astrophysics Data System (ADS)

Baumstark-Khan, C.; Heilmann, J.; Rink, H.

The lens epithelium is the initiation site for the development of radiation induced cataracts. While in the cortex and nucleus radiation interacts with proteins, experimental results from cultured lenses and lens epithelial cells demonstrate mutagenic and cytotoxic effects in the epithelium. It is suggested that incorrectly repaired DNA damage may be lethal in terms of cellular reproduction and also may initiate the development of mutations or transformations in surviving cells. The occurrence of such genetically modified cells may lead to lens opacification. For a quantitative risk estimation for astronauts and space travelers it is necessary to know the radiation's relative biological effectiveness (RBE), because cosmic rays differ significantly from X-rays. RBEs for the induction of DNA strand breaks and the efficiency of repair of these breaks were measured in cultured diploid bovine lens epithelial cells exposed to different LET irradiations. Irradiations were performed either with 300 kV X-rays or at the UNILAC accelerator at GSI. Accelerated ions from Z=8 (O) to Z=92 (U) were used. For strand break measurements hydroxyapatite chromatography of alka-line unwound DNA (overall strand breaks) and non-denaturing filter elution technique (double strand breaks) were applied. Experiments showed that DNA damage occurs as a function of dose, of kinetic energy and of LET. For particles having the same LET the severity of the DNA damage increases with dose. For a given particle dose, as the LET rises, the numbers of DNA strand breaks increase to a maximum and then reach a plateau or decrease. Repair kinetics depend on the fluence (irradiation dose). At any LET value, repair is much slower after heavy ion exposure than after X-irradiation. For ions with an LET of less than 10,000 keV/μm more than 90 percent of the strand breaks induced are repaired within 24 hours. At higher particle fluences, especially for low energetic particles with a very high local density of energy deposition within the particle track, a higher proportion of non-rejoined breaks is found, even after prolonged periods of incubation. At the highest LET value (16,300 keV/μm) no significant repair is observed. These observations are consistent with the current theory of the mechanism of radiation induced cataractogenesis which posts that genomic damage to the epithelial cells surviving the exposure is responsible for lens opacification.

Optical patient interface in femtosecond laser-assisted cataract surgery: contact corneal applanation versus liquid immersion.

PubMed

Talamo, Jonathan H; Gooding, Philip; Angeley, David; Culbertson, William W; Schuele, Georg; Andersen, Daniel; Marcellino, George; Essock-Burns, Emma; Batlle, Juan; Feliz, Rafael; Friedman, Neil J; Palanker, Daniel

2013-04-01

To compare 2 optical patient interface designs used for femtosecond laser-assisted cataract surgery. Optimedica Corp., Santa Clara, California, USA, and Centro Laser, Santo Domingo, Dominican Republic. Experimental and clinical studies. Laser capsulotomy was performed during cataract surgery with a curved contact lens interface (CCL) or a liquid optical immersion interface (LOI). The presence of corneal folds, incomplete capsulotomy, subconjunctival hemorrhage, and eye movement during laser treatment were analyzed using video and optical coherence tomography. The induced rise of intraocular pressure (IOP) was measured in porcine and cadaver eyes. Corneal folds were identified in 70% of the CCL cohort; 63% of these had areas of incomplete capsulotomies beneath the corneal folds. No corneal folds or incomplete capsulotomies were identified in the LOI cohort. The mean eye movement during capsulotomy creation (1.5 sec) was 50 μm with a CCL and 20 μm with an LOI. The LOI cohort had 36% less subconjunctival hemorrhage than the CCL cohort. During suction, the mean IOP rise was 32.4 mm Hg ± 3.4 (SD) in the CCL group and 17.7 ± 2.1 mm Hg in the LOI group. Curved contact interfaces create corneal folds that can lead to incomplete capsulotomy during laser cataract surgery. A liquid interface eliminated corneal folds, improved globe stability, reduced subconjunctival hemorrhage, and lowered IOP rise. Copyright © 2013 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Introduction of a Toric Intraocular Lens to a Non-Refractive Cataract Practice: Challenges and Outcomes

PubMed Central

Kirwan, Clare; Nolan, John M; Stack, Jim; Dooley, Ian; Moore, Johnny; Moore, Tara CB; Beatty, Stephen

2016-01-01

Aim To identify challenges inherent in introducing a toric intraocular lens (IOL) to a non-refractive cataract practice, and evaluate residual astigmatism achieved and its impact on patient satisfaction. Methods Following introduction of a toric IOL to a cataract practice with all procedures undertaken by a single, non-refractive, surgeon (SB), pre-operative, intra-operative and post-operative data was analysed. Attenuation of anticipated post-operative astigmatism was examined, and subjectively perceived visual functioning was assessed using validated questionnaires. Results Median difference vector (DV, the induced astigmatic change [by magnitude and axis] that would enable the initial surgery to achieve intended target) was 0.93D; median anticipated DV with a non-toric IOL was 2.38D. One eye exhibited 0.75D residual astigmatism, compared to 3.8D anticipated residual astigmatism with a non-toric IOL. 100% of respondents reported satisfaction of ≥ 6/10, with 37.84% of respondents entirely satisfied (10/10). 17 patients (38.63%) reported no symptoms of dysphotopsia (dysphoptosia score 0/10), only 3 respondents (6.8%) reported a clinically meaningful level of dysphotopsia (≥ 4/10). Mean post-operative NEI VF-11 score was 0.54 (+/-0.83; scale 0 – 4). Conclusion Use of a toric IOL to manage astigmatism during cataract surgery results in less post-operative astigmatism than a non-toric IOL, resulting in avoidance of unacceptable post-operative astigmatism. PMID:27830188

Biological Effects of Space Radiation and Development of Effective Countermeasures

PubMed Central

Kennedy, Ann R.

2014-01-01

As part of a program to assess the adverse biological effects expected from astronaut exposure to space radiation, numerous different biological effects relating to astronaut health have been evaluated. There has been major focus recently on the assessment of risks related to exposure to solar particle event (SPE) radiation. The effects related to various types of space radiation exposure that have been evaluated are: gene expression changes (primarily associated with programmed cell death and extracellular matrix (ECM) remodeling), oxidative stress, gastrointestinal tract bacterial translocation and immune system activation, peripheral hematopoietic cell counts, emesis, blood coagulation, skin, behavior/fatigue (including social exploration, submaximal exercise treadmill and spontaneous locomotor activity), heart functions, alterations in biological endpoints related to astronaut vision problems (lumbar puncture/intracranial pressure, ocular ultrasound and histopathology studies), and survival, as well as long-term effects such as cancer and cataract development. A number of different countermeasures have been identified that can potentially mitigate or prevent the adverse biological effects resulting from exposure to space radiation. PMID:25258703

Biological effects of space radiation and development of effective countermeasures

NASA Astrophysics Data System (ADS)

Kennedy, Ann R.

2014-04-01

As part of a program to assess the adverse biological effects expected from astronauts' exposure to space radiation, numerous different biological effects relating to astronauts' health have been evaluated. There has been major focus recently on the assessment of risks related to exposure to solar particle event (SPE) radiation. The effects related to various types of space radiation exposure that have been evaluated are: gene expression changes (primarily associated with programmed cell death and extracellular matrix (ECM) remodeling), oxidative stress, gastrointestinal tract bacterial translocation and immune system activation, peripheral hematopoietic cell counts, emesis, blood coagulation, skin, behavior/fatigue (including social exploration, submaximal exercise treadmill and spontaneous locomotor activity), heart functions, alterations in biological endpoints related to astronauts' vision problems (lumbar puncture/intracranial pressure, ocular ultrasound and histopathology studies), and survival, as well as long-term effects such as cancer and cataract development. A number of different countermeasures have been identified that can potentially mitigate or prevent the adverse biological effects resulting from exposure to space radiation.

Delayed effects of proton irradiation in Macaca Mulatta (22-year summary)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Woods, D.H.; Hardy, K.A.; Cox, A.B.

1989-05-15

Lifetime observations on a group of rhesus monkeys indicate that life expectancy loss from exposure to protons in the energy range encountered in the Van Allen belts and solar proton events can be correlated with the dose and energy of radiation. The primary cause of life shortening is nonleukemic cancers. Radiation also increased the rise of endometriosis (an abnormal proliferation of the lining of the uterus in females). Other effects associated with radiation exposures are lowered glucose tolerance and increased incidence of cataracts. Calculations of the relative risk of fatal cancers in the irradiated subjects reveal that the total bodymore » surface dose required to double the risk of death from cancer over a 20-year post exposure period varies with the linear energy transfer (LET) of the radiation. The ability to determine the integrated dose and LET spectrum in space radiation exposures of humans is, therefore, critical to the assessment of lifetime cancer risk.« less

Review Recent progress in identification and characterization of loci associated with sex-linked congenital cataract.

PubMed

Zhang, D D; Du, J Z; Topolewski, J; Wang, X M

2016-07-29

Congenital cataract is a common cause of blindness in children; however, its pathogenesis remains unclear. Genetic factors have been shown to play an important role in the pathogenesis of congenital cataract. The current genetic models of congenital cataract include autosomal dominant, autosomal recessive, and sex-linked inheritance. Sex-linked congenital cataract could be inherited through the X or Y chromosome. Congenital cataract is a symptom associated with several X-linked disorders, including Nance-Horan syndrome, Lowe syndrome, Conradi-Hünermann-Happle syndrome, oculo-facio-cardio-dental syndrome, and Alport syndrome. On the other hand, the mechanism and characteristics of Y-linked congenital cataract remains to be identified. Despite its rarity, sex-linked congenital cataract has been known to seriously affect the quality of life of patients. In this review, we present our current understanding of the genes and loci associated with sex-linked congenital cataract. This could help identify novel approaches for the prevention, early diagnosis, and comprehensive disease treatment.

Barriers to Cataract Surgery in Africa: A Systematic Review.

PubMed

Aboobaker, Shaheer; Courtright, Paul

2016-01-01

Cataract remains the leading cause of blindness in Africa. We performed a systematic literature search of articles reporting barriers to cataract surgery in Africa. PubMed and Google Scholar databases were searched with the terms "barriers, cataract, Africa, cataract surgery, cataract surgical coverage (CSC), and rapid assessment of avoidable blindness (RAAB)." The review covered from 1999 to 2014. In RAAB studies, barriers related to awareness and access were more commonly reported than acceptance. Other type of studies reported cost as the most common barrier. Some qualitative studies tended to report community and family dynamics as barriers to cataract surgery. CSC was lower in females in 88.2% of the studies. The variability in outcomes of studies of barriers to cataract surgery could be due to context and the type of data collection. It is likely that qualitative data will provide a deeper understanding of the complex social, family, community, financial and gender issues relating to barriers to uptake of cataract surgery in Africa.

Induction and repair of DNA strand breaks in bovine lens epithelial cells after high LET irradiation.

PubMed

Baumstark-Khan, C; Heilmann, J; Rink, H

2003-01-01

The lens epithelium is the initiation site for the development of radiation induced cataracts. Radiation in the cortex and nucleus interacts with proteins, while in the epithelium, experimental results reveal mutagenic and cytotoxic effects. It is suggested that incorrectly repaired DNA damage may be lethal in terms of cellular reproduction and also may initiate the development of mutations or transformations in surviving cells. The occurrence of such genetically modified cells may lead to lens opacification. For a quantitative risk estimation for astronauts and space travelers it is necessary to know the relative biological effectiveness (RBE), because the spacial and temporal distribution of initial physical damage induced by cosmic radiation differ significantly from that of X-rays. RBEs for the induction of DNA strand breaks and the efficiency of repair of these breaks were measured in cultured diploid bovine lens epithelial cells exposed to different LET irradiation to either 300 kV X-rays or to heavy ions at the UNILAC accelerator at GSI. Accelerated ions from Z=8 (O) to Z=92 (U) were used. Strand breaks were measured by hydroxyapatite chromatography of alkaline unwound DNA (overall strand breaks). Results showed that DNA damage occurs as a function of dose, of kinetic energy and of LET. For particles having the same LET the severity of the DNA damage increases with dose. For a given particle dose, as the LET rises, the numbers of DNA strand breaks increase to a maximum and then reach a plateau or decrease. Repair kinetics depend on the fluence (irradiation dose). At any LET value, repair is much slower after heavy ion exposure than after X-irradiation. For ions with an LET of less than 10,000 keV micrometers-1 more than 90 percent of the strand breaks induced are repaired within 24 hours. At higher particle fluences, especially for low energetic particles with a very high local density of energy deposition within the particle track, a higher proportion of non-rejoined breaks is found, even after prolonged periods of incubation. At the highest LET value (16,300 keV micrometers-1) no significant repair is observed. These LET-dependencies are consistent with the current mechanistic model for radiation induced cataractogenesis which postulates that genomic damage to the surviving fraction of epithelial cells is responsible for lens opacification. c2003 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

The lens and cataracts.

PubMed

Matthews, Andrew G

2004-08-01

It is conservatively estimated that some form of lens opacity is present in 5% to 7% of horses with otherwise clinically normal eyes.These opacities can range from small epicapsular remnants of the fetal vasculature to dense and extensive cataract. A cataract is defined technically as any opacity or alteration in the optical homogeneity of the lens involving one or more of the following: anterior epithelium, capsule, cortex, or nucleus. In the horse, cataracts rarely involve the entire lens structure (ie, complete cataracts) and are more usually localized to one anatomic landmark or sector of the lens. Complete cataracts are invariably associated with overt and significant visual disability. Focal or incomplete cataracts alone seldom cause any apparent visual dysfunction in affected horses,however.

Ionizing irradiation not only inactivates clonogenic potential in primary normal human diploid lens epithelial cells but also stimulates cell proliferation in a subset of this population.

PubMed

Fujimichi, Yuki; Hamada, Nobuyuki

2014-01-01

Over the past century, ionizing radiation has been known to induce cataracts in the crystalline lens of the eye, but its mechanistic underpinnings remain incompletely understood. This study is the first to report the clonogenic survival of irradiated primary normal human lens epithelial cells and stimulation of its proliferation. Here we used two primary normal human cell strains: HLEC1 lens epithelial cells and WI-38 lung fibroblasts. Both strains were diploid, and a replicative lifespan was shorter in HLEC1 cells. The colony formation assay demonstrated that the clonogenic survival of both strains decreases similarly with increasing doses of X-rays. A difference in the survival between two strains was actually insignificant, although HLEC1 cells had the lower plating efficiency. This indicates that the same dose inactivates the same fraction of clonogenic cells in both strains. Intriguingly, irradiation enlarged the size of clonogenic colonies arising from HLEC1 cells in marked contrast to those from WI-38 cells. Such enhanced proliferation of clonogenic HLEC1 cells was significant at ≥2 Gy, and manifested as increments of ≤2.6 population doublings besides sham-irradiated controls. These results suggest that irradiation of HLEC1 cells not only inactivates clonogenic potential but also stimulates proliferation of surviving uniactivated clonogenic cells. Given that the lens is a closed system, the stimulated proliferation of lens epithelial cells may not be a homeostatic mechanism to compensate for their cell loss, but rather should be regarded as abnormal. This is because these findings are consistent with the early in vivo evidence documenting that irradiation induces excessive proliferation of rabbit lens epithelial cells and that suppression of lens epithelial cell divisions inhibits radiation cataractogenesis in frogs and rats. Thus, our in vitro model will be useful to evaluate the excessive proliferation of primary normal human lens epithelial cells that may underlie radiation cataractogenesis, warranting further investigations.

A Computer Based Cognitive Simulation of Cataract Surgery

DTIC Science & Technology

2011-12-01

for zonular absence, assess for notable lenticular astigmatism ** How and when do you decide to use a capsular tension ring? (Expert) Zonular...INTRODUCTION The Virtual Mentor Cataract Surgery Trainer is a computer based, cognitive simulation of phacoemulsification cataract surgery. It is...the Cataract Trainer. BODY Phacoemulsification cataract surgery (phaco) is a difficult procedure to learn, with little margin for error. As in other

Blindness and cataract surgical services in Atsinanana region, Madagascar.

PubMed

Randrianaivo, Jean-Baptiste; Anholt, R Michele; Tendrisoa, Diarimirindra Lazaharivony; Margiano, Nestor Jean; Courtright, Paul; Lewallen, Susan

2014-01-01

To assess the prevalence and causes of avoidable blindness in Atsinanana Region, Madagascar, with the Rapid Assessment of Avoidable Blindness (RAAB) survey. We analyzed the hospital records to supplement the findings for public health care planning. Only villages within a two-hour walk from a road, about half of the population of Atsinanana was included. Seventy-two villages were selected by population-proportional-to-size sampling. In each village, compact segment sampling was used to select 50 people over age 50 for eye examination using standard RAAB methods. Records at the two hospitals providing cataract surgery in the region were analyzed for information on patients who underwent cataract surgery in 2010. Cataract incidence rate and target cataract surgery rate (CSR) was modeled from age-specific prevalence of cataract. The participation rate was 87% and the sample prevalence of blindness was 1.96%. Cataract was responsible for 64% and 85.7% of blindness and severe visual impairment, respectively. Visual impairment was due to cataract (69.4%) and refractive error (14.1%). There was a strong positive correlation between cataract surgical rate by district and the proportion of people living within 2 hours of a road. There were marked differences in the profiles of the cataract patients at the two facilities. The estimated incidence of cataract at the 6/18 level was 2.4 eyes per 100 people over age 50 per year. Although the survey included only people with reasonable access, the main cause of visual impairment was still cataract. The incidence of cataract is such that it ought to be possible to eliminate it as a cause of visual impairment, but changes in service delivery at hospitals and strategies to improve access will be necessary for this change.

Trauma-induced pemphigus: a case series of 36 patients.

PubMed

Daneshpazhooh, Maryam; Fatehnejad, Mina; Rahbar, Ziba; Balighi, Kamran; Ghandi, Narges; Ghiasi, Maryam; Abedini, Robabeh; Lajevardi, Vahideh; Chams-Davatchi, Cheyda

2016-02-01

Pemphigus is a group of autoimmune diseases characterized by intraepidermal acantholytic blisters. Isomorphic responses, or Koebner phenomenon (KP), defined as the appearance of typical lesions of a disease following trauma are rarely reported in pemphigus. Our aim was to present patients who developed new pemphigus lesions as a result of skin trauma. The medical files of pemphigus patients from the Autoimmune Bullous Diseases Research Center, who had a history of trauma before the onset or flare of their disease, between 1999 and 2013 were reviewed. Thirty-six pemphigus vulgaris (PV) patients had a history of trauma. Thirteen patients developed new-onset PV and the other 23 had previously been diagnosed with PV. Pemphigus lesions developed most often following major surgeries including abdominal, orthopedic, and chest surgeries as well as dental procedures, blunt physical trauma, and skin surgeries. Moreover, post-cataract laser surgery, burns, radiation therapy, and physiotherapy were also shown to induce pemphigus. Mean time between trauma and lesions was 4.7 weeks for recurrent PV and 15.0 weeks for new-onset PV. Unnecessary surgery and blunt trauma should be avoided in pemphigus patients. Furthermore, posttraumatic pemphigus should be suspected in poorly healing surgical wounds and confirmatory biopsies are mandatory. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

Aging and Health: Cataracts

MedlinePlus

... Community Home › Aging & Health A to Z › Cataracts Font size A A A Print Share Glossary Basic ... every year in the US. The Most Common Types of Cataracts Cataracts are categorized depending on their ...

Development of cataract and corneal opacity in mice due to radon exposure

NASA Astrophysics Data System (ADS)

Abdelkawi, S. A.; Abo-Elmagd, M.; Soliman, H. A.

This work investigates the radiation damage on the eye of albino mice exposed to effective radon doses ranging from 20.92 to 83.68 mSv. These doses were taken over 2-8 weeks using a radon chamber constructed by the National Institute for Standard (Egypt). The guidance on the quality assurance program for radon measurements was followed. Therefore, the estimated doses received by the laboratory animals meet the requirements of national standardE The refractive index(RI) and protein concentration were measured for soluble proteins of both corneas and lenses. In addition, the sodium dodecyle sulfate polyacrylamide gel electrophoresis (SDSPAGE) technique was used. The results show increasing of the RI of both cornea and lens proteins and decreasing in total protein concentration of exposed animals. These results were accompanied with changes in the SDSPAGE profile for both cornea and lens. Therefore, radon exposure produces substantial hazards to the cornea and lens of experimental animals and has a crucial role in the development of cataract and corneal opacity.

Aetiology of congenital and paediatric cataract in an Australian population

PubMed Central

Wirth, M G; Russell-Eggitt, I M; Craig, J E; Elder, J E; Mackey, D A

2002-01-01

Background/aim: Paediatric cataract is a major cause of childhood blindness. Several genes associated with congenital and paediatric cataracts have been identified. The aim was to determine the incidence of cataract in a population, the proportion of hereditary cataracts, the mode of inheritance, and the clinical presentation. Methods: The Royal Children's Hospital and the Royal Victorian Eye and Ear Hospital have a referral base for almost all paediatric patients with cataracts in south eastern Australia. The database contains cases seen over the past 25 years. The medical histories of these patients were reviewed. Results: 421 patients with paediatric cataract were identified, which gives an estimated incidence of 2.2 per 10 000 births. Of the 342 affected individuals with a negative family history, 50% were diagnosed during the first year of life, and 56/342 (16%) were associated with a recognised systemic disease or syndrome. Unilateral cataract was identified in 178/342 (52%) of sporadic cases. 79 children (from 54 nuclear families) had a positive family history. Of these 54 families, 45 were recruited for clinical examination and DNA collection. Ten nuclear families were subsequently found to be related, resulting in four larger pedigrees. Thus, 39 families have been studied. The mode of inheritance was autosomal dominant in 30 families, X linked in four, autosomal recessive in two, and uncertain in three. In total, 178 affected family members were examined; of these 8% presented with unilateral cataracts and 43% were diagnosed within the first year of life. Conclusions: In the paediatric cataract population examined, approximately half of the patients were diagnosed in the first year of life. More than 18% had a positive family history of cataracts. Of patients with hereditary cataracts 8% presented with unilateral involvement. Identification of the genes that cause paediatric and congenital cataract should help clarify the aetiology of some sporadic and unilateral cataracts. PMID:12084750

Visual outcome and impact on quality of life after surgeries differ in children operated for unilateral and bilateral cataract (Pune study 2011)

PubMed Central

Paryani, Mukesh; Khandekar, Rajiv B.; Dole, Kuldeep; Dharmadhikari, Sheetal; Rishikeshi, Nikhil

2012-01-01

Background: We compared vision and quality of life (VQL) of children aged 5-15 years and operated for unilateral and bilateral cataract between 2008 and 2010 in western India. Materials and Methods: In this cohort study, ophthalmologists assessed vision, anterior and posterior segment of eyes with cataract. Children completed a functional vision questionnaire (LVP-FVQ). Follow up at 6 months after surgery included the best corrected visual acuity (BCVA), FVQ and eye assessment. The improvement of BCVA and quality of life were compared in group of unilateral and bilateral cataract. Result: A total of 20 (70%) bilateral and 7 (39%) unilateral cataract were operated within 1 month of detection. All 48 eyes with bilateral cataract were congenital and 12 (67%) unilateral cataract were traumatic. Among bilateral group, 27 eyes [56.2% (95% confidence interval (CI) 44.4-72.2)] and in unilateral group 11 eyes [61.1% (95% CI 38.6-83.6)] had vision ≥ 20/60 at 6 months follow up. The visual gain was significantly higher in children who were operated between 1 month and 1 year of detection (adjusted Odds ratio (OR) = 15.6 P = 0.03). Positive impact on VQL in bilateral group was noted in 50%, 27%, and 13% children for subscale of distant vision, near vision, and field of vision, respectively. There was positive impact in these subscales among children with unilateral cataract. Thirty percent eyes with bilateral cataract and 22% of eyes with unilateral cataract improved their vision. Surgery within 1 month of cataract was significant predictor of improved vision (OR = 16.6 P = 0.02). Conclusion: Vision and VQL improved in children with unilateral and bilateral cataract. However, it was better 6 months following surgery in children with bilateral cataract than in children with unilateral cataract. PMID:23439722

Pre-cataract surgery test using speckle pattern

NASA Astrophysics Data System (ADS)

Jutamulia, Suganda; Wihardjo, Erning; Widjaja, Joewono

2016-11-01

A laser diode device for pre cataract surgery test is proposed. The operation is based on the speckle generated on the retina by the cataract lens, when the cataract lens is illuminated with a coherent laser light.

Relationship of cataract symptoms of preoperative patients and vision-related quality of life.

PubMed

Lee, Jae Eun; Fos, Peter J; Sung, Jung Hye; Amy, Brian W; Zuniga, Miguel A; Lee, Won Jae; Kim, Jae Chang

2005-10-01

This study was conducted in an attempt to describe the status of cataract symptoms of preoperative cataract patients, as well as to determine the relationship between cataract symptom and vision-related quality of life measures. A cross-sectional study design was used. Study subjects were selected using non-probabilistic methods. The study sample consisted of 132 patients scheduled for cataract surgery in one eye. Information was obtained from study subjects by conducting face-to-face interviews. Study subjects were adult cataract patients at Samsung and Kunyang General Hospitals in Seoul, Korea, and Tulane University Hospital and Clinics in New Orleans, Louisiana, United States of America. Degree to which study subjects were "bothered" by cataract symptoms was measured by using the 5-item Cataract Symptom Scores (CSS). The number of symptoms, highest scored symptom among the five, number of symptoms extremely bothering, and the mean of cataract symptom score were created based on the CSS measure. Vision-related quality of life was assessed by using the Visual Function 14 Items (VF-14) and Global Measure of Vision (GMV) for trouble and satisfaction. The symptoms "blurry vision" and "worsening of vision" were most frequently reported. The symptom "colors looking different" was rarely reported among preoperative cataract patients. The degree to which study subjects were bothered by "blurry vision" and "seeing glare, halo, or rings" was highly associated with visual function, visual trouble, and visual satisfaction. Multiple regression analysis revealed that the newly developed cataract symptom-related scales, as well as total amount of degree to which study subjects were "bothered" by symptoms were highly related to vision-related quality of life measures. These relationships were persistent after controlling for major socio-demographic variables. The results indicate that cataract symptoms are highly associated with vision-related quality of life. The results also suggest that the number of symptoms, highest scored symptom among the five, number of symptoms extremely bothering, and the mean cataract symptom scores should be considered an important cataract symptom-related scale when analyzing quality of life, including cataract symptom.

M-BAND analysis of chromosome aberration induced by Fe-ions in human epithelial cells cultured in 3-dimensional matrices

NASA Astrophysics Data System (ADS)

Hada, Megumi; Cucinotta, Francis A.; Wu, Honglu

Energetic heavy ions pose a great health risk to astronauts in extended ISS and future lunar and Mars missions. High-LET heavy ions are particularly effective in causing various biological effects, including cell inactivation, genetic mutations, cataracts and cancer induction. Most of these biological endpoints are closely related to chromosomal damage, which can be utilized as a biomarker for radiation insults. Previously, we had studied lowand high-LET radiationinduced chromosome aberrations in human epithelial cells cultured in 2-dimension (2D) using the multicolor banding fluorescence in situ hybridization (mBAND) technique. However, it has been realized that the biological response to radiation insult in a 2D cellular environment in vitro can differ significantly from the response in 3-dimension (3D) or at the actual tissue level. In this study, we cultured human epithelial cells in 3D to provide a more suitable model for human tissue. Human mammary epithelial cells (CH184B5F5/M10) were grown in Matrigel to form 3D structures, and exposed to Fe-ions at NASA Space Radiation Laboratory (NSRL) at the Brookhaven National Laboratory or 137 Cs-gamma radiation source at the University of Texas MD Anderson Cancer Center. After exposure, cells were allowed to repair for 16hr before dissociation and subcultured at low density in 2D. G2 and metaphase chromosomes in the first cell cycle were collected using a chemical-induced premature chromosome condensation (PCC) technique, and chromosome aberrations were analyzed using mBAND technique. With this technique, individually painted chromosomal bands on one chromosome allowed the identification of interchromosomal aberrations (translocation to unpainted chromosomes) and intrachromosomal aberrations (inversions and deletions within a single painted chromosome). Our data indicate a significant difference of the chromosome aberration yield between 2D and 3D cell cultures for gamma exposures, but not for Fe ion exposures. Therefore, the RBE for chromosome aberrations obtained in a 2D model may not represent accurately the RBE for tissues.

Number of People Blind or Visually Impaired by Cataract Worldwide and in World Regions, 1990 to 2010.

PubMed

Khairallah, Moncef; Kahloun, Rim; Bourne, Rupert; Limburg, Hans; Flaxman, Seth R; Jonas, Jost B; Keeffe, Jill; Leasher, Janet; Naidoo, Kovin; Pesudovs, Konrad; Price, Holly; White, Richard A; Wong, Tien Y; Resnikoff, Serge; Taylor, Hugh R

2015-10-01

To estimate prevalence and number of people visually impaired or blind due to cataract. Based on the Global Burden of Diseases Study 2010 and ongoing literature research, we examined how many people were affected by moderate to severe vision impairment (MSVI; presenting visual acuity <6/18, ≥3/60) and blindness (presenting visual acuity <3/60) due to cataract. In 2010, of overall 32.4 million blind and 191 million vision impaired, 10.8 million people were blind and 35.1 million were visually impaired due to cataract. Cataract caused worldwide 33.4% of all blindness in 2010, and 18.4% of all MSVI. These figures were lower in the high-income regions (<15%) and higher (>40%) in South and Southeast Asia and Oceania. From 1990 to 2010, the number of blind or visually impaired due to cataract decreased by 11.4% and by 20.2%, respectively; the age-standardized global prevalence of cataract-related blindness and MSVI reduced by 46% and 50%, respectively, and the worldwide crude prevalence of cataract-related blindness and MSVI reduced by 32% and 39%, respectively. The percentage of global blindness and MSVI caused by cataract decreased from 38.6% to 33.4%, and from 25.6% to 18.4%, respectively. This decrease took place in almost all world regions, except East Sub-Saharan Africa. In 2010, one in three blind people was blind due to cataract, and one of six visually impaired people was visually impaired due to cataract. Despite major improvements in terms of reduction of prevalence, cataract remains a major public health problem.

Epidemiological correlates of cataract cases in tertiary health care center in rural area of maharashtra.

PubMed

Avachat, Shubhada Sunil; Phalke, Vaishali; Kambale, Suchit

2014-01-01

The most recent estimates from World Health Organization (WHO) reveal that 47.8% of global blindness is due to cataract. Cataract has been documented to be the most significant cause of bilateral blindness in India. The most recent estimates from WHO reveal that 47.8% of global blindness is due to cataract and in south Asia region which includes India, 51% of blindness is due to cataract. In India cataract is the principal cause of blindness accounting for 62.6% cases of blindness. The key to the success of the Global Vision 2020: The right to sight initiative is a special effort to tackle cataract blindness which includes estimation of magnitude of the problem and understanding factors associated with it. Therefore, a study was conducted in the hospital to estimate the magnitude of cataract and study various epidemiological factors associated with it. A cross-sectional study was conducted in a tertiary health center in rural area. Total 746 patients who availed services from ophthalmology department during study period were included in the study and relevant data was collected from them. Data analysis was done by percentages, proportions, and tests of significance (Chi-square test). Out of 746 patients, 400 (53.6%) were suffering from cataract. Senile cataract was the most common cause (54%). Fifty-five percent patients were in the age group of 60-80 years and majority of them were from low socioeconomic strata. The prevalence of cataract in a medical college hospital in rural area was 53.6%. Age, sex, and educational status were significantly associated with cataract.

Nutritional modulation of cataract

USDA-ARS?s Scientific Manuscript database

Cataract, or lens opacification, remains a major cause of blindness worldwide. Cataracts reduce vision in over eighty million people, causing blindness in eighteen million people. The number afflicted by cataract will increase dramatically as the proportion of the elderly global population increase...

Fruit and vegetable intake and vitamins C and E are associated with a reduced prevalence of cataract in a Spanish Mediterranean population

PubMed Central

2013-01-01

Background Cataract is among the major causes of vision impairment and blindness worldwide. Epidemiological studies support the role of antioxidants in the etiology of cataract, but the evidence for one specific antioxidant over another is inconsistent. Few studies have examined the association of cataract with fruit and vegetable intake with inconclusive results. In the present study, the relationship between cataract and fruit and vegetable intake and dietary and blood levels of carotenoids, vitamins C and E were examined in a Spanish Mediterranean population. Methods The present work is an analysis of data from 599 elderly ( ≥ 65 years) participants from the Spanish segment of the EUREYE study. This is a European multi-center cross-sectional population-based study. Cataract was diagnosed using a slit-lamp examination and defined as any lens opacity in either eye or evidence of its removal (cataract extraction). Energy-adjusted intake of fruit and vegetables and antioxidant vitamins was estimated using a semi-quantitative food frequency questionnaire. Plasma concentrations of vitamin C were analyzed by a colorimetric method and carotenoids and α-tocopherol by a HPLC method. The associations between cataract and quartiles of fruit and vegetable intake and plasma antioxidants were investigated using logistic regression models. Results Of the 599 elderly recruited, 433 (73%) had cataract or cataract extraction, 54% were women and 46% were men. After adjustments, increasing quartiles of combined fruit and vegetable intake were associated with decreasing reduction of odds of cataract or cataract extraction, (P for trend = 0.008). Increasing quartiles of dietary intakes from 107 mg/d of vitamin C showed a significant decreasing association with prevalence of cataract or cataract extraction (P for trend = 0.047). For vitamin E, a protective association was found from intakes from 8 mg/d, but no linear trend was observed across quartiles of intake (P for trend = 0.944). Conclusions High daily intakes of fruit and vegetables and vitamins C and E were associated with a significantly decreased of the prevalence of cataract or cataract surgery. This study reinforces the WHO recommendations on the benefits of diets rich in fruit and vegetables. PMID:24106773

Ancestry, Socioeconomic Status, and Age-Related Cataract in Asians: The Singapore Epidemiology of Eye Diseases Study.

PubMed

Chua, Jacqueline; Koh, Jia Yu; Tan, Ava Grace; Zhao, Wanting; Lamoureux, Ecosse; Mitchell, Paul; Wang, Jie Jin; Wong, Tien Yin; Cheng, Ching-Yu

2015-11-01

To determine the prevalence of age-related cataract and its ancestral and socioeconomic risk factors in a multi-ethnic Asian population. Population-based, cross-sectional study. A total of 10 033 adults (3353 Chinese, 3280 Malays, and 3400 Indians) aged >40 years in the Singapore Epidemiology of Eye Diseases Study. Study participants were invited for a structured interview and received a standardized comprehensive eye examination. Digital lens photographs were taken from eyes of each participant and graded for nuclear, cortical, and posterior subcapsular (PSC) cataract, following the Wisconsin Cataract Grading System. Prevalence data were compared with the Blue Mountains Eye Study (BMES) in Australia. Information on medical and lifestyle factors was collected using questionnaires and blood samples. To increase the precision of racial definition, genetic ancestry was derived from genome-wide single nucleotide polymorphism markers using principal component analysis. Regression models were used to investigate the association of cataract with socioeconomic factors (education and income) and genetic ancestry. Age-related cataract. A total of 8750 participants (94.0%) had gradable lens photographs. The age-standardized prevalence of cataract surgery in Chinese (16.0%), Malays (10.6%), and Indians (20.2%) was higher than in white subjects (4.1%). We found the age-standardized cataract prevalence in Chinese (30.4%), Malays (37.8%), and Indians (33.1%) was higher than in whites (18.5%). Cataract was 1.5 to 2 times more common in Asians and began 10 years earlier than in white subjects. Malays had significantly higher age-standardized prevalence of nuclear, cortical, and PSC cataract than Chinese (P<0.001). The severity of nuclear, cortical, and PSC cataract was significantly correlated with genetic ancestry in our South East Asian population. Less education and lower income were associated with cataract for Chinese and Indians but not Malays. The presence of visual impairment associated with cataract was higher in people aged ≥60 years and Malays. We showed that people of different Asian ethnicities had a higher prevalence and earlier age of onset of cataract than Europeans. People of Malay ancestry have a greater severity for all cataract subtypes than people of Chinese ancestry. Education and income were associated with cataract for certain Asian subgroups. Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Calculation of the change in corneal astigmatism following cataract extraction.

PubMed

Cravy, T V

1979-01-01

Obtaining a minimal amount of postoperative astigmatism following cataract surgery is becoming increasingly important. One aspect of the patient's surgery which should not be overlooked is the preoperative keratometry which provides a basis for preoperative planning of surgical technique to be used and a point of reference for determining the amount of change in astigmatism produced by the surgery. Analysis of the surgically induced change in astigmatism using the calculations described in this paper will allow the surgeon to evaluate his own techniques and to maximize his potential for obtaining consistently good postoperative astigmatic results without the need for suture removal. The method presented is based upon concepts in common use in surgical ophthalmology and requires only simple mathematical procedures, familiar to all with a background in algebra and trigonometry.

Inhibition of copper-mediated aggregation of human γD-crystallin by Schiff bases.

PubMed

Chauhan, Priyanka; Muralidharan, Sai Brinda; Velappan, Anand Babu; Datta, Dhrubajyoti; Pratihar, Sanjay; Debnath, Joy; Ghosh, Kalyan Sundar

2017-06-01

Protein aggregation, due to the imbalance in the concentration of Cu 2+ and Zn 2+ ions is found to be allied with various physiological disorders. Copper is known to promote the oxidative damage of β/γ-crystallins in aged eye lens and causes their aggregation leading to cataract. Therefore, synthesis of a small-molecule 'chelator' for Cu 2+ with complementary antioxidant effect will find potential applications against aggregation of β/γ-crystallins. In this paper, we have reported the synthesis of different Schiff bases and studied their Cu 2+ complexation ability (using UV-Vis, FT-IR and ESI-MS) and antioxidant activity. Further based on their copper complexation efficiency, Schiff bases were used to inhibit Cu 2+ -mediated aggregation of recombinant human γD-crystallin (HGD) and β/γ-crystallins (isolated from cataractous human eye lens). Among these synthesized molecules, compound 8 at a concentration of 100 μM had shown ~95% inhibition of copper (100 μM)-induced aggregation. Compound 8 also showed a positive cooperative effect at a concentration of 5-15 μM on the inhibitory activity of human αA-crystallin (HAA) during Cu 2+ -induced aggregation of HGD. It eventually inhibited the aggregation process by additional ~20%. However, ~50% inhibition of copper-mediated aggregation of β/γ-crystallins (isolated from cataractous human eye lens) was recorded by compound 8 (100 μM). Although the reductive aminated products of the imines showed better antioxidant activity due to their lower copper complexing ability, they were found to be non-effective against Cu 2+ -mediated aggregation of HGD.

Smoking and its association with cataract: results of the Andhra Pradesh eye disease study from India.

PubMed

Krishnaiah, Sannapaneni; Vilas, Kovai; Shamanna, Bindiganavale R; Rao, Gullapalli N; Thomas, Ravi; Balasubramanian, Dorairajan

2005-01-01

To investigate the associations between tobacco smoking and various forms of cataracts among the people of a state in India. A population-based cross-sectional epidemiologic study was conducted in the south Indian state of Andhra Pradesh (AP). A total of 10,293 subjects of all ages from one urban and three rural areas, representative of the population of AP, were interviewed, and each underwent a detailed dilated ocular evaluation by trained professionals. Data were analyzed for 7416 (72%) of the subjects aged >15 years. Increasing age was significantly associated with all cataract types and history of prior cataract surgery and/or total cataract. In multivariate analyses, after adjusting for all demographic factors and for history of smoking, females, illiterate persons, and those belonging to the extreme lower socioeconomic status group were found to have a significantly higher prevalence of any cataract, adjusted odds ratio (OR)=1.60 (95% confidence interval [CI]: 1.24-1.96), 1.46 (95% CI: 1.17-1.70), and 1.92 (95% CI: 1.14-3.24), respectively. After adjustment, cigarette and cigar smokers had a significantly higher prevalence of any cataract, adjusted OR=1.51 (95% CI: 1.10-2.06) and 1.44 (95% CI: 1.12-1.84), respectively, compared with those who had never smoked ("never-smokers"). A significantly higher prevalence of nuclear, cortical cataract, and history of prior cataract surgery and/ or total cataract was found among cigarette smokers. A dose-response relationship was seen with respect to cigarette and cigar smoking. After adjustment, compared with never-smokers, cigarette smokers who smoked heavily (>14 "pack-years" of smoking) had a significantly higher prevalence of nuclear cataract (OR=1.65; 95% CI: 1.10-2.59), cortical cataract (OR=2.11; 95% CI: 1.38-3.24), and history of prior cataract surgery and/or total cataract (OR=2.10; 95% CI: 1.05-4.22). Nuclear cataract was significantly higher in cigar smokers (adjusted OR=1.55; 95% CI: 1.16-2.01) and in cigar smokers who smoked heavily (>21 person-years of smoking; OR=1.50; 95% CI: 1.10-1.95), compared with never-smokers. Consistent with other studies, tobacco smoking was strongly associated with a higher prevalence of nuclear and cortical cataracts and history of prior cataract surgery in this population. These findings suggest yet another need to educate the community on the importance of cessation of tobacco smoking and perhaps incorporating an antismoking message into school health programs.

[15 years after the accident at the Chernobyl Nuclear Power Plant].

PubMed

Buldakov, L A; Gus'kova, A K

2002-01-01

Health effects as a result of the accident at the Chernobyl nuclear power plant occurred in 1986 are considered in the paper. Wrong prognosis of the health effects with respect to mortality and morbidity among the population exposed to low radiation doses is shown. Proven increase in thyroid cancer cases among people who were children aged from 0 to 18 at the time of the accident is shown. Linear relationship between thyroid cancer cases and dose to thyroid ranged from 0.2 to 4.0 Gy is considered. An additional absolute risk of thyroid cancer in children varies in the range 1.9-2.6 cases per 10(4) person-year Gy. During the fifteen years following the accident no cases of acute and chronic radiation sickness have been revealed because the population living in contaminated areas received low radiation doses. Also, exposures to low radiation doses did not result in excess of malignant tumors among population. In some cases the outcomes of acute radiation sickness were as follows: radiation damages to the skin, cancer cataracts, development of oncopathology.

Cataract - Multiple Languages

MedlinePlus

... Section Cataract - العربية (Arabic) Bilingual PDF Health Information Translations Chinese, Simplified (Mandarin dialect) (简体中文) Expand Section Cataract - ... Chinese, Simplified (Mandarin dialect)) Bilingual PDF ... Health Information Translations Chinese, Traditional (Cantonese dialect) (繁體中文) Expand Section Cataract - ...

Lenticular abnormalities in children.

PubMed

Khokhar, Sudarshan; Agarwal, Tushar; Kumar, Gaurav; Kushmesh, Rakhi; Tejwani, Lalit Kumar

2012-01-01

To study the lenticular problems in children presenting at an apex institute. Retrospective analysis of records (< 14 years) of new lens clinic cases was done. Of 1,047 children, 687 were males. Mean age at presentation was 6.35 ± 4.13 years. Developmental cataract was seen in 45.6% and posttraumatic cataract in 29.7% of patients. Other abnormalities were cataract with retinal detachment, persistent hyperplastic primary vitreous, subluxated lens, micro/spherophakia, cataract secondary to uveitis, intraocular lens complications, cataract with choroidal coloboma, and visual axis opacification. Developmental and posttraumatic cataracts were the most common abnormalities. Delayed presentation is of concern. Copyright 2012, SLACK Incorporated.

Tropomyosin 2 heterozygous knockout in mice using CRISPR-Cas9 system displays the inhibition of injury-induced epithelial-mesenchymal transition, and lens opacity

PubMed Central

Shibata, Teppei; Shibata, Shinsuke; Ishigaki, Yasuhito; Kiyokawa, Etsuko; Ikawa, Masahito; Singh, Dhirendra P.; Sasaki, Hiroshi; Kubo, Eri

2018-01-01

The process of epithelial–mesenchymal transition (EMT) of lens epithelial cells (LECs) after cataract surgery contributes to tissue fibrosis, wound healing and lens regeneration via a mechanism not yet fully understood. Here, we show that tropomyosin 2 (Tpm2) plays a critical role in wound healing and lens aging. Posterior capsular opacification (PCO) after lens extraction surgery was accompanied by elevated expression of Tpm2. Tpm2 heterozygous knockout mice, generated via the clustered regularly interspaced short palindromic repeat/ Cas9 (CRISPR/Cas9) system showed promoted progression of cataract with age. Further, injury-induced EMT of the mouse lens epithelium, as evaluated histologically and by the expression patterns of Tpm1 and Tpm2, was attenuated in the absence of Tpm2. In conclusion, Tpm2 may be important in maintaining lens physiology and morphology. However, Tpm2 is involved in the progression of EMT during the wound healing process of mouse LECs, suggesting that inhibition of Tpm2 may suppress PCO. PMID:29510160

Effects of enhanced UV-B radiation on secondary metabolites in forage plants and potential consequences for multiple trophic responses involving mammalian herbivores

NASA Astrophysics Data System (ADS)

Thines, Nicole J.; Bassman, John H.; Shipley, Lisa A.; Slusser, James R.

2004-10-01

Herbivores represent the interface between primary production and higher trophic levels. The effects of enhanced UV-B radiation on microbes, invertebrate herbivores, and detritivores has received limited study in both terrestrial and aquatic ecosystems. However, although direct effects (e.g. melanoma, cataracts) on mammals have been documented, indirect effects (e.g., resulting from changes in plant chemistry) of enhanced UV-B on mammalian herbivores have not been evaluated. Although the diet of mammalian herbivores has little effect on nutritional quality for their associated predators, to the extent changes in plant chemistry affect aspects of population dynamics (e.g., growth, fecundity, densities), higher trophic levels can be affected. In this study, different forage species of varying inherent levels of key secondary metabolites are being grown in the field under either ambient or ambient plus supplemental UV-B radiation simulating a 15% stratospheric ozone depletion for Pullman, Washington. At various time intervals, foliage is being sampled and analyzed for changes in secondary metabolites and other attributes. Using controlled feeding trials, changes in plant secondary metabolites are being related to preference and digestibility in specialist and generalist mammalian hindgut herbivores, digestion in ruminants and non-ruminants, and to selected aspects of population dynamics in mammalian herbivores. Results suggest how UV-B-induced changes in plant secondary chemistry affect animal nutrition, and thus animal productivity in a range of mammalian herbivores. Reductions in palatability and digestibility of plant material along with reductions in fecundity and other aspects of population dynamics could have significant economic ramifications for farmers, ranchers and wildlife biologists.

Significance of Interactions of Low Molecular Weight Crystallin Fragments in Lens Aging and Cataract Formation*

PubMed Central

Santhoshkumar, Puttur; Udupa, Padmanabha; Murugesan, Raju; Sharma, K. Krishna

2008-01-01

Analysis of aged and cataract lenses shows the presence of increased amounts of crystallin fragments in the high molecular weight aggregates of water-soluble and water-insoluble fractions. However, the significance of accumulation and interaction of low molecular weight crystallin fragments in aging and cataract development is not clearly understood. In this study, 23 low molecular mass (<3.5-kDa) peptides in the urea-soluble fractions of young, aged, and aged cataract human lenses were identified by mass spectroscopy. Two peptides, αB-(1–18) (MDIAIHHPWIRRPFFPFH) and βA3/A1-(59–74) (SD(N)AYHIERLMSFRPIC), present in aged and cataract lens but not young lens, and a third peptide, γS-(167–178) (SPAVQSFRRIVE) present in all three lens groups were synthesized to study the effects of interaction of these peptides with intact α-, β-, and γ-crystallins and alcohol dehydrogenase, a protein used in aggregation studies. Interaction of αB-(1–18) and βA3/A1-(59–74) peptides increased the scattering of light by β- and γ-crystallin and alcohol dehydrogenase. The ability of α-crystallin subunits to function as molecular chaperones was significantly reduced by interaction with αB-(1–18) and βA3/A1-(59–74) peptides, whereas γS peptide had no effect on chaperone-like activity of α-crystallin. The βA3/A1-(59–74 peptide caused a 5.64-fold increase in αB-crystallin oligomeric mass and partial precipitation. Replacing hydrophobic residues in αB-(1–18) and βA3/A1-(59–74) peptides abolished their ability to induce crystallin aggregation and light scattering. Our study suggests that interaction of crystallin-derived peptides with intact crystallins could be a key event in age-related protein aggregation in lens and cataractogenesis. PMID:18227073

Exome Sequencing of 18 Chinese Families with Congenital Cataracts: A New Sight of the NHS Gene

PubMed Central

Sun, Wenmin; Xiao, Xueshan; Li, Shiqiang; Guo, Xiangming; Zhang, Qingjiong

2014-01-01

Purpose The aim of this study was to investigate the mutation spectrum and frequency of 34 known genes in 18 Chinese families with congenital cataracts. Methods Genomic DNA and clinical data was collected from 18 families with congenital cataracts. Variations in 34 cataract-associated genes were screened by whole exome sequencing and then validated by Sanger sequencing. Results Eleven candidate variants in seven of the 34 genes were detected by exome sequencing and then confirmed by Sanger sequencing, including two variants predicted to be benign and the other pathogenic mutations. The nine mutations were present in 9 of the 18 (50%) families with congenital cataracts. Of the four families with mutations in the X-linked NHS gene, no other abnormalities were recorded except for cataract, in which a pseudo-dominant inheritance form was suggested, as female carriers also had different forms of cataracts. Conclusion This study expands the mutation spectrum and frequency of genes responsible for congenital cataract. Mutation in NHS is a common cause of nonsyndromic congenital cataract with pseudo-autosomal dominant inheritance. Combined with our previous studies, a genetic basis could be identified in 67.6% of families with congenital cataracts in our case series, in which mutations in genes encoding crystallins, genes encoding connexins, and NHS are responsible for 29.4%, 14.7%, and 11.8% of families, respectively. Our results suggest that mutations in NHS are the common cause of congenital cataract, both syndromic and nonsyndromic. PMID:24968223

[Analysis of cataract surgical rate and its influencing factors in Shanghai, China].

PubMed

Zhu, Ming-ming; Zhu, Jian-feng; Zou, Hai-dong; He, Xian-gui; Zhao, Rong; Lu, Li-na

2013-12-17

To explore the cataract surgical rate (CSR) of Shanghai from 2006 to 2012 and examine its influencing factors. As of 2003, a cataract surgery registration form had been filled by physicians after every cataract surgery in Shanghai. The local eye disease prevention team then entered the relevant information into the Shanghai Cataract Operations Database. Based upon this database, CSR of Shanghai was calculated. And the number of cataract surgeries was compared between Shanghai urban and suburban districts as well as among different medical institutions. The overall CSR in Shanghai increased from 1741 in 2006 to 2313 in 2012. In 2012, CSR in urban districts reached 6013 while it stood at 460 and 584 in inner and outer suburb districts respectively. The number of hospitals performing cataract surgery in urban districts was much more than that in suburbs. And the average number of cataract surgeries per hospital per year in suburbs was only one third of that (748 cases) in urban areas. The number of cataract surgeries at in private hospitals increased rapidly during the past 7 years. The number of 1921 cases was nearly twice as many as that at tertiary hospitals in 2012. Phacoemulsification surgery was the most popular surgical choice for cataract removal, accounting for 98.40% of total cataract surgeries in 2012. Until 2012, CSR in Shanghai dropped below the target of World Health Organization (WHO). A low level of CSR in suburbs is a major influencing factor for the overall level of CSR in Shanghai.

Photochemical effects in the lens from near infrared radiation?

NASA Astrophysics Data System (ADS)

Söderberg, Per G.; Al-Saqry, Riyadh; Schulmeister, Karl; Gallichanin, Konstantin; Kronschläger, Martin; Yu, Zhaohua

2009-02-01

Conclusion: The current data are consistent with a potential photochemical effect of in vivo exposure of the crystalline lens to near infrared radiation since the onset of cataract after in just above threshold dose was at least 18 hrs delayed after the exposure. Materials and methods: The eyes of 6 weeks old Sprague-Dawley rats were exposed unilaterally in vivo to 1090 nm, 6.2 W quasi-top hat spatial distribution with a 3 mm spot on the anterior lens surface within the dilated pupil. First, four exposure time groups of rats were exposed to increasing exposure times. At 24 hrs after exposure, the difference of light scattering between the lenses from the same animal was measured. Then, based on the first experiment, four post-exposure time groups were exposed unilaterally in vivo to 8 s of 1090 nm, 6.2 W quasi-top hat spatial distribution with a 3 mm spot on the anterior lens surface within the dilated pupil. After, the intended post-exposure time, the difference of light scattering between the lenses from the same animal was measured. Results: A 3 mm spot of 6.2 W induces light scattering in the lens with exposures of at least 8 s. Further, after 8 s of 6.2 W within a 3 mm spot on the lens surface, the light scattering increase in the lens was delayed at least 18 hrs after the exposure.

UV Induced Degradation of Polycarbonate-Based Lens Materials and Implications for the Heath Care Field

NASA Astrophysics Data System (ADS)

Harkay, J. R.; Henry, Jerry

2006-10-01

Experimental research is being carried out at Keene State at the undergraduate level that utilizes facilities in both physics and chemistry to study the effects of mono- and polychromatic UV radiation from various sources, including a Deuterium lamp, a solarization unit (at Polyonics, a local industry), and the Sun, to study the photodegradation of polycarbonate-based lens materials used to produce eyewear. Literature in the field of optometry and ophthalmology indicates a correlation between exposure to the UVB band of natural sunlight and the onset of cataract formation, as well as other eye disorders. The public is usually advised that plastic eyeglass lenses will provide protection from this damaging radiation. It is well known that polycarbonate plastic ``yellows'' when exposed to intense sunlight and, particularly, UV light^1,2, either via photo-Fries rearrangement or by a photooxidative process, forming polyconjugated systems and is an industrial concern primarily for cosmetic reasons. We have preliminary data, however, that indicates that the yellowing'' is an indication of a more sinister problem in the case of eyeglasses in that it is accompanied by an increase in transmissivity in the UVB band where the wearer expects and needs protection. Our group includes a local optometrist who will share results with peers in his field. [1] A. Andrady, J. Polymer Sci., 42, 1991 [2] E. P. Gorelov, Inst. Khim. Fiz., Russian Federation

Cataract Blindness in Osun State, Nigeria: Results of a Survey

PubMed Central

Kolawole, Olubayo U.; Ashaye, Adeyinka O.; Mahmoud, Abdulraheem O.; Adeoti, Caroline O.

2012-01-01

Purpose: To estimate the burden of blindness and visual impairment due to cataract in Egbedore Local Government Area of Osun State, Nigeria. Materials and Methods: Twenty clusters of 60 individuals who were 50 years or older were selected by systematic random sampling from the entire community. A total of 1,183 persons were examined. Results: The age- and sex-adjusted prevalence of bilateral cataract-related blindness (visual acuity (VA) < 3/60) in people of 50 years and older was 2.0% (95% confidence interval (CI): 1.6–2.4%). The Cataract Surgical Coverage (CSC) (persons) was 12.1% and Couching Coverage (persons) was 11.8%. The age- and sex-adjusted prevalence of bilateral operable cataract (VA < 6/60) in people of 50 years and older was 2.7% (95% CI: 2.3–3.1%). In this last group, the cataract intervention (surgery + couching) coverage was 22.2%. The proportion of patients who could not attain 6/60 vision after surgery were 12.5, 87.5, and 92.9%, respectively, for patients who underwent intraocular lens (IOL) implantation, cataract surgery without IOL implantation and those who underwent couching. “Lack of awareness” (30.4%), “no need for surgery” (17.6%), cost (14.6%), fear (10.2%), “waiting for cataract to mature” (8.8%), AND “surgical services not available” (5.8%) were reasons why individuals with operable cataract did not undergo cataract surgery. Conclusions: Over 600 operable cataracts exist in this region of Nigeria. There is an urgent need for an effective, affordable, and accessible cataract outreach program. Sustained efforts have to be made to increase the number of IOL surgeries, by making IOL surgery available locally at an affordable cost, if not completely free. PMID:23248537

Prevalence and risk factors for cataract in diabetes: Sankara Nethralaya Diabetic Retinopathy Epidemiology and Molecular Genetics Study, report no. 17.

PubMed

Raman, Rajiv; Pal, Swakshyar Saumya; Adams, James Subrat Kumar; Rani, Padmaja Kumari; Vaitheeswaran, Kulothungan; Sharma, Tarun

2010-12-01

To report the prevalence of cataract and its subtypes in patients with type 2 diabetes mellitus and the risk factors associated with these cataracts. One thousand two hundred eighty-three eligible subjects with type 2 diabetes mellitus, enrolled from a cross-sectional study, underwent examination at the base hospital. Lens opacity was graded by a trained ophthalmologist according to the Lens Opacity Classification System (LOCS) III system. The age- and sex-adjusted prevalence of cataract in the study was 65.7% (95% confidence interval [CI], 65.6-65.8). Mixed cataracts were more common than monotype ones (41.6% vs. 19.4%). The prevalence of cataract was higher in women, subjects with known diabetes and those with longer duration of diabetes (51.4%, 50.3%, and 64.5%, respectively). The risk factors for any type of cataract were increasing age (odds ratio [OR], 1.14; 95% CI, 1.11-1.16), macroalbuminuria (OR, 4.61; 95% CI, 1.56-13.59) and increasing glycosylated hemoglobin (OR, 1.92; 95% CI, 1.22-3.00); higher hemoglobin (OR, 0.38; 95% CI, 0.22-0.64) was the protective factor. The risk factors for nuclear cataract included increasing age (OR, 1.15) and high serum triglycerides (OR, 6.83). For cortical cataract, increasing age (OR, 1.14) and poor glycemic control (OR, 2.43) were the risk factors; increasing hemoglobin (OR, 0.41) was the protective factor. For posterior subcapsular cataract, the risk factors included increasing age (OR, 1.11), being of the female sex (OR, 9.12), employment (OR, 9.80), and duration of diabetes (OR, 21.37). Nearly two thirds of the diabetic population showed evidence of cataract; mixed cataracts were more common than the monotypes ones.

Carbohydrate nutrition, glycemic index, and the 10-y incidence of cataract.

PubMed

Tan, Jennifer; Wang, Jie Jin; Flood, Victoria; Kaushik, Shweta; Barclay, Alan; Brand-Miller, Jennie; Mitchell, Paul

2007-11-01

Although dietary carbohydrates are thought to play a role in cataractogenesis, few epidemiologic studies have examined links between carbohydrate nutrition and cataract. We investigated the associations between dietary glycemic index (GI), glycemic load (GL), total carbohydrate intake, and 10-y incident nuclear, cortical, and posterior subcapsular cataract. Of 3654 baseline participants in an Australian population aged >/=49 y (1992-1994), 933 were seen after 5 and/or 10 y, had completed a detailed semiquantitative food-frequency questionnaire, had no previous cataract surgery or baseline cataract, and had photographs taken to assess incident cataract with the Wisconsin Cataract Grading System. Dietary information was collected with a validated food questionnaire. GI was calculated from a customized database of Australian foods. GI, GL, and all other nutrients were energy adjusted. Hazard ratios (HRs) and 95% CIs were calculated with the use of discrete logistic models. After age, sex, diabetes, and other factors were controlled for, each SD increase in GI significantly predicted incident cortical cataract (HR: 1.19; 95% CI: 1.01, 1.39). Participants within the highest compared with the lowest quartile of GI were more likely to develop incident cortical cataract (HR: 1.77; 95% CI: 1.13, 2.78; P for trend = 0.035). These findings were similar after excluding participants with diabetes, although they were slightly attenuated and marginally nonsignificant (HR: 1.16; 95% CI: 0.98, 1.37, per SD increase in GI). No association was found between GI and nuclear or posterior subcapsular cataract and between GL or carbohydrate quantity and any cataract subtype. In an Australian cohort, poorer dietary carbohydrate quality, reflected by high GI, predicted incident cortical cataract.

Cataract surgical coverage and outcome in the Tibet Autonomous Region of China

PubMed Central

Bassett, K L; Noertjojo, K; Liu, L; Wang, F S; Tenzing, C; Wilkie, A; Santangelo, M; Courtright, P

2005-01-01

Background: A recently published, population based survey of the Tibet Autonomous Region (TAR) of China reported on low vision, blindness, and blinding conditions. This paper presents detailed findings from that survey regarding cataract, including prevalence, cataract surgical coverage, surgical outcome, and barriers to use of services. Methods: The Tibet Eye Care Assessment (TECA) was a prevalence survey of people from randomly selected households from three of the seven provinces of the TAR (Lhoka, Nakchu, and Lingzhr), representing its three main environmental regions. The survey, conducted in 1999 and 2000, assessed visual acuity, cause of vision loss, and eye care services. Results: Among the 15 900 people enumerated, 12 644 were examined (79.6%). Cataract prevalence was 5.2% and 13.8%, for the total population, and those over age 50, respectively. Cataract surgical coverage (vision <6/60) for people age 50 and older (85–90% of cataract blind) was 56% overall, 70% for men and 47% for women. The most common barriers to use of cataract surgical services were distance and cost. In the 216 eyes with cataract surgery, 60% were aphakic and 40% were pseudophakic. Pseudophakic surgery left 19% of eyes blind (<6/60) and an additional 20% of eyes with poor vision (6/24–6/60). Aphakic surgery left 24% of eyes blind and an additional 21% of eyes with poor vision. Even though more women remained blind than men, 28% versus 18% respectively, the different was not statistically significant (p = 0.25). Conclusions: Cataract surgical coverage was remarkably high despite the difficulty of providing services to such an isolated and sparse population. Cataract surgical outcome was poor for both aphakic and pseudophakic surgery. Two main priorities are improving cataract surgical quality and cataract surgical coverage, particularly for women. PMID:15615736

Current status of cataract blindness and Vision 2020: the right to sight initiative in India.

PubMed

Murthy, Gvs; Gupta, Sanjeev K; John, Neena; Vashist, Praveen

2008-01-01

India is a signatory to the World Health Organization resolution on Vision 2020: The right to sight. Efforts of all stakeholders have resulted in increased number of cataract surgeries performed in India, but the impact of these efforts on the elimination of avoidable blindness is unknown. Projection of performance of cataract surgery over the next 15 years to determine whether India is likely to eliminate cataract blindness by 2020. Data from three national level blindness surveys in India over three decades, and projected age-specific population till 2020 from US Census Bureau were used to develop a model to predict the magnitude of cataract blindness and impact of Vision 2020: the right to sight initiatives. Using age-specific data for those aged 50+ years it was observed that prevalence of blindness at different age cohorts (above 50 years) reduced over three decades with a peak in 1989. Projections show that among those aged 50+ years, the quantum of cataract surgery would double (3.38 million in 2001 to 7.63 million in 2020) and cataract surgical rate would increase from 24025/million 50+ in 2001 to 27817/million 50+ in 2020. Though the prevalence of cataract blindness would decrease, the absolute number of cataract blind would increase from 7.75 million in 2001 to 8.25 million in 2020 due to a substantial increase in the population above 50 years in India over this period. Considering existing prevalence and projected incidence of cataract blindness over the period 2001-2020, visual outcomes after cataract surgery and sight restoration rate, elimination of cataract blindness may not be achieved by 2020 in India.

Folic Acid, Vitamin B6, and Vitamin B12 in Combination and Age-Related Cataract in a Randomized Trial of Women.

PubMed

Christen, William G; Glynn, Robert J; Chew, Emily Y; Albert, Christine M; Manson, JoAnn E

2016-01-01

To examine the incidence of cataract and cataract extraction in a trial of folic acid and vitamins B6 and B12. In a randomized, double-masked, placebo-controlled trial, 5442 female health professionals aged 40 years or older with preexisting cardiovascular disease (CVD) or three or more CVD risk factors were randomly assigned to receive a combination of folic acid (2.5 mg/day), vitamin B6 (50 mg/day), and vitamin B12 (1 mg/day), or placebo. A total of 3925 of these women did not have a diagnosis of cataract at baseline and were included in this analysis. The primary endpoint was age-related cataract, defined as an incident age-related lens opacity, responsible for a reduction in best-corrected visual acuity to 20/30 or worse, based on self-report confirmed by medical record review. Extraction of incident age-related cataract was a secondary endpoint of the trial. During an average of 7.3 years of treatment and follow-up, 408 cataracts and 275 cataract extractions were documented. There were 215 cataracts in the combination treatment group and 193 in the placebo group (hazard ratio, HR, 1.10, 95% confidence interval, CI, 0.90-1.33; p = 0.36). For the secondary endpoint of cataract extraction, there were 155 in the combination treatment group and 120 in the placebo group (HR 1.28, 95% CI 1.01-1.63; p = 0.04). In this large-scale randomized trial of women at high risk of CVD, daily supplementation with a combination of folic acid, vitamin B6, and vitamin B12 had no significant effect on cataract, but may have increased the risk of cataract extraction.

Surgery for cataracts in people with age-related macular degeneration

PubMed Central

Casparis, Heather; Lindsley, Kristina; Kuo, Irene C; Sikder, Shameema; Bressler, Neil M

2017-01-01

Background Cataract and age-related macular degeneration (AMD) are common causes of decreased vision that often occur simultaneously in people over age 50. Although cataract surgery is an effective treatment for cataract-induced visual loss, some clinicians suspect that such an intervention may increase the risk of worsening of underlying AMD and thus have deleterious effects on vision. Objectives The objective of this review was to evaluate the effectiveness and safety of cataract surgery compared with no surgery in eyes with AMD. Search methods We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (2016, Issue 11), Ovid MEDLINE, Epub Ahead of Print, In-Process & Other Non-Indexed Citations, Ovid MEDLINE Daily (January 1946 to December 2016), Embase (January 1980 to December 2016), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982to December 2016), the ISRCTN registry (www.isrctn.com/editAdvancedSearch), ClinicalTrials.gov (www.clinicaltrials.gov), and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 2 December 2016. Selection criteria We included randomized controlled trials (RCTs) and quasi-randomized trials that enrolled participants whose eyes were affected by both cataract and AMD in which cataract surgery was compared with no surgery. Data collection and analysis Two review authors independently evaluated the search results against the inclusion and exclusion criteria. Two review authors independently extracted data, assessed risk of bias for included studies, and graded the certainty of evidence. We followed methods as recommended by Cochrane. Main results We included two RCTs with a total of 114 participants (114 study eyes) with visually significant cataract and AMD. We identified no ongoing trials. Participants in each RCT were randomized to immediate cataract surgery (within two weeks of enrollment) or delayed cataract surgery (six months after enrollment). The risk of bias was unclear for most domains in each study; one study was registered prospectively. In one study conducted in Australia outcomes were reported only at six months (before participants in the delayed-surgery group had cataract surgery). At six months, the immediate-surgery group showed mean improvement in best-corrected visual acuity (BCVA) compared with the delayed-surgery group (mean difference (MD) -0.15 LogMAR, 95% confidence interval (CI) -0.28 to -0.02; 56 participants; moderate-certainty evidence). In the other study, conducted in Austria, outcomes were reported only at 12 months (12 months after participants in the immediate-surgery group and six months after participants in the delayed-surgery group had cataract surgery). There was uncertainty as to which treatment group had better improvement in distance visual acuity at 12 months (unit of measure not reported; very low-certainty evidence). At 12 months, the mean change from baseline between groups in cumulated drusen or geographic atrophy area size was small and there was uncertainty which, if either, of the groups was favored (MD 0.76, 95% CI -8.49 to 10.00; 49 participants; low-certainty evidence). No participant in one study had exudative AMD develop in the study eye during 12 months of follow-up; in the other study, choroidal neovascularization developed in the study eye of 1 of 27 participants in the immediate-surgery group versus 0 of 29 participants in the delayed-surgery group at six months (risk ratio 3.21, 95% CI 0.14 to 75.68; 56 participants; very low-certainty evidence). Quality of life was measured using two different questionnaires. Scores on the Impact of Vision Impairment (IVI) questionnaire suggested that the immediate-surgery group fared better regarding vision-related quality of life than the delayed-surgery group at six months (MD in IVI logit scores 1.60, 95% CI 0.61 to 2.59; low-certainty evidence). However, we could not analyze scores from the Visual Function-14 (VF-14) questionnaire from the other study due to insufficient data. No postoperative complication was reported from either study. Authors' conclusions At this time, it is not possible to draw reliable conclusions from the available data as to whether cataract surgery is beneficial or harmful in people with AMD after 12 months. Although cataract surgery provides short-term (six months) improvement in BCVA in eyes with AMD compared with no surgery, it is unclear whether the timing of surgery has an effect on long-term outcomes. Physicians must make recommendations to their AMD patients regarding cataract surgery based on experience and clinical judgment until large controlled trials are conducted and their findings published. There is a need for prospective RCTs in which cataract surgery is compared with no surgery in people with AMD to better evaluate whether cataract surgery is beneficial or harmful in all or a subset of AMD patients. However, ethical considerations preclude withholding surgery, or delaying it for several years, if it may be a potentially beneficial treatment. Designers of future trials are encouraged to utilize existing standardized systems for grading cataract and AMD and for measuring key outcomes: visual acuity, change in visual acuity, worsening of AMD, quality of life measures, and adverse events. PMID:28206671

Towards a Better Understanding of the Effects of UV on Atlantic Walruses, Odobenus rosmarus rosmarus: A Study Combining Histological Data with Local Ecological Knowledge

PubMed Central

Martinez-Levasseur, Laura M.; Furgal, Chris M.; Hammill, Mike O.; Burness, Gary

2016-01-01

Walruses, Odobenus rosmarus, play a key role in the Arctic ecosystem, including northern Indigenous communities, which are reliant upon walruses for aspects of their diet and culture. However, walruses face varied environmental threats including rising sea-water temperatures and decreasing ice cover. An underappreciated threat may be the large amount of solar ultraviolet radiation (UV) that continues to reach the Arctic as a result of ozone loss. UV has been shown to negatively affect whales. Like whales, walrus skin is unprotected by fur, but in contrast, walruses spend long periods of time hauled-out on land. In this study, we combined the results of histological analyses of skin sections from five Atlantic walruses, Odobenus rosmarus rosmarus, collected in Nunavik (Northern Quebec, Canada) with qualitative data obtained through the interviews of 33 local walrus hunters and Inuit Elders. Histological analyses allowed us to explore UV-induced cellular lesions and interviews with experienced walrus hunters and Elders helped us to study the incidences and temporal changes of UV-induced gross lesions in walruses. At the microscopic scale, we detected a range of skin abnormalities consistent with UV damage. However, currently such UV effects do not seem to be widely observed at the whole-animal level (i.e., absence of skin blistering, erythema, eye cataract) by individuals interviewed. Although walruses may experience skin damage under normal everyday UV exposure, the long-term data from local walrus hunters and Inuit Elders did not report a relation between the increased sun radiation secondary to ozone loss and walrus health. PMID:27049757

Implications of the implementation of the revised dose limit to the lens of the eye: the view of IRPA professionals.

PubMed

Broughton, J; Cantone, M C; Ginjaume, M; Shah, B; Czarwinski, R

2015-06-01

In April 2011, the International Commission on Radiological Protection issued a statement on reduction of the equivalent dose limits for the lens of the eye, and strongly recommended its consideration in the revision of the International Atomic Energy Agency's International Basic Safety Standards on Radiation Protection. The reduced dose limit was incorporated in the final version of the Basic Safety Standards. As significant concern was expressed by radiation protection professionals worldwide, the International Radiation Protection Association (IRPA) established a task group to assess the impact of implementation of the revised dose limit for the lens of the eye for occupational exposure. IRPA Associate Societies (ASs) were asked for their views using a questionnaire addressing three topics: implications for dosimetry, implications for methods of protection, and wider implications. The responses received indicate various methods of approach and express different points of view, reflecting nuances of particular ASs or specific professional groups. Topic experts nominated by ASs were selected to assist with collation of responses, and a report was produced by the task group. Conclusions were drawn on the three issues, including potential cost implications. A number of recommendations were drawn from the responses received including: the request for more understanding about the relationship between exposure of the lens of the eye and cataract formation, and further guidance to assist implementation; the importance of economic and social considerations when introducing the limits into national regulations; the need to propose or define procedures related to employment of people with existing or pre-cataract conditions; and the practical aspects relating to dosimetry and protective equipment. © The International Society for Prosthetics and Orthotics Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Dynamic Light-Scattering Probe Used for the Very Early Detection of Cataracts and to Measure Response to Therapy (or Treatment)

NASA Technical Reports Server (NTRS)

Ansari,Rafat R.; Clark, John I.; King, James F.

2002-01-01

Half of all blindness worldwide is due to cataracts, and 34 million Americans over the age of 65 have cataracts. This figure is expected to rise to 70 million by the year 2030. Currently, no medical treatment is available to prevent or halt the progression of a cataract; nor is there any way to reverse a cataract once it has been detected by conventional methods. The only known treatment is surgical removal of the lens. It is estimated that over $5 billion will be spent this year for the treatment of cataract patients in the United States alone. According to Carl Kupfer, M.D., former Director of the National Eye Institute at the National Institutes of Health, "A delay in cataract formation of about 10 years would reduce the prevalence of visually disabling cataracts by about 45 percent." However, this vision remains a dream because of the lack of objective methods that can be used to detect cataracts very early and, hence, can be used for screening potential anticataract drugs. This is about to change. The National Eye Institute and NASA entered into a formal interagency agreement in late 1996 to develop and test a dynamic light-scattering (DLS) device to detect the earliest changes due to cataract formation. The new DLS probe developed by Dr. Ansari at the NASA Glenn Research Center is several orders of magnitude more sensitive than conventional clinical systems. This ultrahigh sensitivity enables the probe to detect the onset of a cataract before it has any effect on vision and allows researchers to test the effectiveness of anticataract drugs in reversing cataracts. This device (see the following illustration) was originally designed to study transport phenomena in microgravity fluid physics experiments onboard the space shuttle orbiters and space station. It will be very useful in testing anticataract drugs to halt or reverse the progression of cataracts during longitudinal clinical trials.

Cerebral gigantism (Sotos' syndrome) and cataracts.

PubMed

Yeh, H; Price, R L; Lonsdale, D

1978-01-01

A five-year-old girl with cerebral gigantism (Sotos' syndrome) and cataracts is described. Sotos' syndrome, characterized by generalized gigantism with normal endocrine studies has rarely been reported with ocular abnormalities and never with cataracts. It is important to study any child with cataracts for systemic disease.

The results of ab interno laser thermal sclerostomy combined with cataract surgery versus trabeculectomy combined with cataract surgery 6 to 12 months postoperatively.

PubMed

Kendrick, R; Kollarits, C R; Khan, N

1996-07-01

When cataract surgery and glaucoma surgery are combined, the theoretical advantages of pressure control, removal of the visual impairment, and protection against an increase in intraocular pressure (IOP) in the immediate postoperative period are gained. The authors' objective was to determine whether ab interno laser thermal sclerostomy (LTS) combined with cataract surgery would be as effective as trabeculectomy combined with cataract surgery. Ab interno LTS was compared with trabeculectomy, retrospectively, for patients who had undergone combined cataract and glaucoma surgery. There was no significant difference in the numbers of patients using no medications or fewer medications at 6 and 12 months. There was a greater reduction in IOP in the LTS group. LTS may be better than trabeculectomy in combined cataract and glaucoma surgery because it reduces the IOP more. Compared with trabeculectomy, LTS is simpler to perform and adds less operating time to cataract surgery. Continued follow-up is recommended.

Clinical Applications of Wavefront Refraction

PubMed Central

Bruce, Adrian S.; Catania, Louis J.

2014-01-01

ABSTRACT Purpose To determine normative reference ranges for higher-order wavefront error (HO-WFE), compare these values with those in common ocular pathologies, and evaluate treatments. Methods A review of 17 major studies on HO-WFE was made, involving data for a total of 31,605 subjects. The upper limit of the 95% confidence interval (CI) for HO-WFE was calculated from the most comprehensive of these studies using normal healthy patients aged 20 to 80 years. There were no studies identified using the natural pupil size for subjects, and for this reason, the HO-WFE was tabulated for pupil diameters of 3 to 7 mm. Effects of keratoconus, pterygium, cataract, and dry eye on HO-WFE were reviewed and treatment efficacy was considered. Results The calculated upper limit of the 95% CI for HO-WFE in a healthy normal 35-year-old patient with a mesopic pupil diameter of 6 mm would be 0.471 μm (471 nm) root-mean-square or less. Although the normal HO-WFE increases with age for a given pupil size, it is not yet completely clear how the concurrent influence of age-related pupillary miosis affects these findings. Abnormal ocular conditions such as keratoconus can induce a large HO-WFE, often in excess of 3.0 μm, particularly attributed to coma. For pterygium or cortical cataract, a combination of coma and trefoil was more commonly induced. Nuclear cataract can induce a negative spherical HO-WFE, usually in excess of 1.0 μm. Conclusions The upper limit of the 95% CI for HO-WFE root-mean-square is about 0.5 μm with normal physiological pupil sizes. With ocular pathologies, HO-WFE can be in excess of 1.0 μm, although many devices and therapeutic and surgical treatments are reported to be highly effective at minimizing HO-WFE. More accurate normative reference ranges for HO-WFE will require future studies using the subjects’ natural pupil size. PMID:25216319

Mitochondria-targeted plastoquinone derivatives as tools to interrupt execution of the aging program. 4. Age-related eye disease. SkQ1 returns vision to blind animals.

PubMed

Neroev, V V; Archipova, M M; Bakeeva, L E; Fursova, A Zh; Grigorian, E N; Grishanova, A Yu; Iomdina, E N; Ivashchenko, Zh N; Katargina, L A; Khoroshilova-Maslova, I P; Kilina, O V; Kolosova, N G; Kopenkin, E P; Korshunov, S S; Kovaleva, N A; Novikova, Yu P; Philippov, P P; Pilipenko, D I; Robustova, O V; Saprunova, V B; Senin, I I; Skulachev, M V; Sotnikova, L F; Stefanova, N A; Tikhomirova, N K; Tsapenko, I V; Shchipanova, A I; Zinovkin, R A; Skulachev, V P

2008-12-01

Mitochondria-targeted cationic plastoquinone derivative SkQ1 (10-(6'-plastoquinonyl) decyltriphenylphosphonium) has been investigated as a potential tool for treating a number of ROS-related ocular diseases. In OXYS rats suffering from a ROS-induced progeria, very small amounts of SkQ1 (50 nmol/kg per day) added to food were found to prevent development of age-induced cataract and retinopathies of the eye, lipid peroxidation and protein carbonylation in skeletal muscles, as well as a decrease in bone mineralization. Instillation of drops of 250 nM SkQ1 reversed cataract and retinopathies in 3-12-month-old (but not in 24-month-old) OXYS rats. In rabbits, experimental uveitis and glaucoma were induced by immunization with arrestin and injections of hydroxypropyl methyl cellulose to the eye anterior sector, respectively. Uveitis was found to be prevented or reversed by instillation of 250 nM SkQ1 drops (four drops per day). Development of glaucoma was retarded by drops of 5 microM SkQ1 (one drop daily). SkQ1 was tested in veterinarian practice. A totally of 271 animals (dogs, cats, and horses) suffering from retinopathies, uveitis, conjunctivitis, and cornea diseases were treated with drops of 250 nM SkQ1. In 242 cases, positive therapeutic effect was obvious. Among animals suffering from retinopathies, 89 were blind. In 67 cases, vision returned after SkQ1 treatment. In ex vivo studies of cultivated posterior retina sector, it was found that 20 nM SkQ1 strongly decreased macrophagal transformation of the retinal pigmented epithelial cells, an effect which might explain some of the above SkQ1 activities. It is concluded that low concentrations of SkQ1 are promising in treating retinopathies, cataract, uveitis, glaucoma, and some other ocular diseases.

The advanced glaucoma intervention study, 6: effect of cataract on visual field and visual acuity. The AGIS Investigators.

PubMed

2000-12-01

To investigate the effect of cataract on visual function and the role of cataract in explaining a race-treatment interaction in outcomes of glaucoma surgery. The Advanced Glaucoma Intervention Study (AGIS) enrolled 332 black patients (451 eyes) and 249 white patients (325 eyes) with advanced glaucoma. Eyes were randomly assigned to an argon laser trabeculoplasty (ALT)-trabeculectomy-trabeculectomy sequence or a trabeculectomy-ALT-trabeculectomy sequence. From the AGIS experience with cataract surgery during follow-up, we estimated the expected change in visual function scores from before cataract surgery to after cataract surgery. Then, for eyes with cataract not removed, we used these estimates of expected change to adjust visual function scores for the presumed effects of cataract. In turn, we used the adjusted scores to obtain cataract-adjusted main outcome measures. Average percent of eyes with decrease of visual field (APDVF) and average percent of eyes with decrease of visual acuity (APDVA). Within the 2 months before cataract surgery, visual acuity was better in eyes of white patients than of black patients by an average of approximately 2 lines on the visual acuity test chart. Cataract surgery improved visual acuity and visual field defect scores, with the amounts of improvement greater when preoperative visual acuity was lower. Adjustments for cataract brought about the following relative reductions: for APDVF, a relative reduction of 5% to 11% in black patients and 9% to 11% in white patients; for APDVA, a relative reduction of 45% to 49% in black patients and 31% to 38% in white patients; and for the APDVF and APDVA race-treatment interactions, relative reductions of 25% and 45%, respectively. On average, visual function scores improved after cataract surgery. The findings of reduced race-treatment interactions after adjustment for cataract do not alter our earlier conclusion that the AGIS 7-year results support use of the ALT-trabeculectomy-trabeculectomy sequence for black patients and of the trabeculectomy-ALT-trabeculectomy sequence for white patients without life-threatening health problems. The choice of treatment should take into account individual patient characteristics and needs.

Comparison of surgically induced astigmatism between femtosecond laser and manual clear corneal incisions for cataract surgery.

PubMed

Diakonis, Vasilios F; Yesilirmak, Nilufer; Cabot, Florence; Kankariya, Vardhaman P; Kounis, George A; Warren, Daniel; Sayed-Ahmed, Ibrahim O; Yoo, Sonia H; Donaldson, Kendall

2015-10-01

To assess the surgically induced corneal astigmatism (SIA) introduced by femtosecond laser-assisted clear corneal incisions (CCIs) for cataract extraction and to compare it with the SIA of manually created CCIs. Bascom Palmer Eye Institute, Miller School of Medicine, Miami, Florida, USA. Prospective nonrandomized comparative case series. Eyes received femtosecond laser-assisted CCIs (Group 1) or manual CCIs (Group 2). The surgical plan included 1 primary and 1 secondary port; the sites of the incisions were the same in both groups and were diametrically opposed between the right eye and left eye. The SIA was assessed using the preoperative and 1-month postoperative keratometric values obtained from corneal topography examinations. This study included 72 eyes of 68 patients with a mean age of 69.0 years ± 9.87 (SD) (range 36 to 90 years). Thirty-six eyes received femtosecond laser-assisted CCIs (Group 1) and 36 received manual CCIs (Group 2). The mean preoperative topographic corneal astigmatism was -1.19 ± 0.68 diopters (D) (range 0 to 2.50 D) and -0.92 ± 0.63 D (range 0.10 to 2.45 D) for Group 1 and Group 2, respectively, whereas, 1 month after cataract surgery, it was -1.16 ± 0.63 D (range 0.20 to 2.57 D) and -0.95 ± 0.64 D (range 0.21 to 2.37 D), respectively. Multivariate vector analysis revealed no statistically significant difference between the 2 groups for preoperative astigmatism, postoperative astigmatism, and SIA (P > .05 for all comparisons between Group 1 and Group 2). Femtosecond laser-assisted and manual corneal incisions for cataract surgery did not appear to significantly alter corneal astigmatism, whereas they showed comparable SIA. Drs. Yoo and Donaldson are speakers for and consultants to Alcon Surgical, Inc., and Abbott Medical Optics, Inc. No other author has a financial or proprietary interest in any material or method mentioned. Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Inheritance of congenital cataracts and microphthalmia in the Miniature Schnauzer.

PubMed

Gelatt, K N; Samuelson, D A; Bauer, J E; Das, N D; Wolf, E D; Barrie, K P; Andresen, T L

1983-06-01

Congenital cataracts and microphthalmia in the Miniature Schnauzer were inherited as an autosomal recessive trait. Eighteen matings of affected X affected Miniature Schnauzers resulted in 87 offspring with congenital cataracts and microphthalmia (49 males/38 females). Two matings of congenital cataractous and microphthalmic Miniature Schnauzers (2 females) X a normal Miniature Schnauzer (1 male) yielded 11 clinically normal Miniature Schnauzers (7 males/4 females). Eighteen matings of congenital cataractous and microphthalmic Miniature Schnauzers (6 males) X carrier Miniature Schnauzers (9 females) produced 81 offspring; 39 exhibited congenital cataracts and microphthalmia (20 males/19 females) and 42 had clinically normal eyes (17 males/25 females).

Carbon footprint and cost-effectiveness of cataract surgery.

PubMed

Venkatesh, Rengaraj; van Landingham, Suzanne W; Khodifad, Ashish M; Haripriya, Aravind; Thiel, Cassandra L; Ramulu, Pradeep; Robin, Alan L

2016-01-01

This article raises awareness about the cost-effectiveness and carbon footprint of various cataract surgery techniques, comparing their relative carbon emissions and expenses: manual small-incision cataract surgery (MSICS), phacoemulsification, and femtosecond laser-assisted cataract surgery. As the most commonly performed surgical procedure worldwide, cataract surgery contributes significantly to global climate change. The carbon footprint of a single phacoemulsification cataract surgery is estimated to be comparable to that of a typical person's life for 1 week. Phacoemulsification has been estimated to be between 1.4 and 4.7 times more expensive than MSICS; however, given the lower degree of postoperative astigmatism and other potential complications, phacoemulsification may still be preferable to MSICS in relatively resource-rich settings requiring high levels of visual function. Limited data are currently available regarding the environmental and financial impact of femtosecond laser-assisted cataract surgery; however, in its current form, it appears to be the least cost-effective option. Cataract surgery has a high value to patients. The relative environmental impact and cost of different types of cataract surgery should be considered as this treatment becomes even more broadly available globally and as new technologies are developed and implemented.

Three hundred and three dogs with cataracts seen in Rio de Janeiro, Brazil.

PubMed

Baumworcel, Natasha; Soares, Ana M B; Helms, Gustavo; Rei, Paulo R L; Castro, Maria Cristina N

2009-01-01

To describe the most common canine breeds affected with cataracts in Rio de Janeiro. Three hundred and three dogs were included in this retrospective study. Animal ages ranged from 6 months to 14.8 years. All records of dogs seen by the Ophthalmology Service of Policlínica Veterinária Botafogo between January 2005 and June 2008 were reviewed. Animals with cataracts were separated, and breed and age were evaluated. Most of the dogs presented with cataracts were Toy Poodles with a mean age of 8.2 years, followed by Cocker Spaniels and Bichon Frises. The percentage of Toy Poodles affected with cataracts was 13.8% while 33.3% of Bichon Frise was diagnosed with cataracts. Toy Poodles are a popular breed in Rio de Janeiro. Without regulations on breeding, the prevalence of cataracts may increase rapidly. Furthermore, due to the relatively late onset of cataract formation in the Toy Poodle (mean 8.2 years of age), affected animals may have produced several litters of puppies. This study emphasizes the importance of screening for the presence of inherited ocular abnormalities such as cataracts prior to breeding.

Impact on the Japanese atomic bomb survivors of radiation received from the bombs.

PubMed

Cullings, Harry M

2014-02-01

The Radiation Effects Research Foundation (RERF) studies various cohorts of Japanese atomic bomb survivors, the largest being the Life Span Study (LSS), which includes 93,741 persons who were in Hiroshima or Nagasaki at the times of the bombings; there are also cohorts of persons who were exposed in utero and survivors' children. This presentation attempts to summarize the total impact of the radiation from the bombs on the survivors from both an individual perspective (both age-specific and integrated lifetime risk, along with a measure of life expectancy that describes how the risk affects the individual given age at exposure) and a group perspective (estimated numbers of excess occurrences in the cohort), including both early and late effects. As survivors' doses ranged well into the acutely lethal range at closer distances, some of them experienced acute signs and symptoms of radiation exposure in addition to being at risk of late effects. Although cancer has always been a primary concern among late effects, estimated numbers of excess cancers and hematopoietic malignancies in the LSS are a small fraction of the total due to the highly skewed dose distribution, with most survivors receiving small doses. For example, in the latest report on cancer incidence, 853 of 17,448 incident solid cancers were estimated to be attributable to radiation from the bombs. RERF research indicates that risk of radiation-associated cancer varies among sites and that some benign tumors such as uterine myoma are also associated with radiation. Noncancer late effects appear to be in excess in proportion to radiation dose but with an excess relative risk about one-third that of solid cancer and a correspondingly small overall fraction of cases attributable to radiation. Specific risks were found for some subcategories, particularly circulatory disease, including stroke and precedent conditions such as hypertension. Radiation-related cataract in the atomic bomb survivors is well known, with evidence in recent years of risk at lower dose levels than previously appreciated. In addition to somatic effects, survivors experienced psychosocial effects such as uncertainty, social stigma, or rejection, and other social pressures. Developmental deficits associated with in utero exposure, notably cognitive impairment, have also been described. Interaction of radiation with other risk factors has been demonstrated in relation to both cancer and noncancer diseases. Current research interests include whether radiation increases risk of diabetes or conditions of the eye apart from cataract, and there continues to be keen interest as to whether there are heritable effects in survivors' children, despite negative findings to date. Introduction of Impact on the Japanese Atomic- Bomb Survivors (Video 1:52, http://links.lww.com/HP/A29).

A link between maternal malnutrition and depletion of glutathione in the developing lens: a possible explanation for idiopathic childhood cataract?

PubMed

Kumar, Deepa; Lim, Julie C; Donaldson, Paul J

2013-11-01

Lens cataract is the leading cause of blindness in developing countries. While cataract is primarily a disease of old age and is relatively rare in children, accounting for only four per cent of global blindness, childhood cataract is responsible for a third of the economic cost of blindness. While many of the causes of cataract in children are known, over half of childhood cataracts are idiopathic with no known cause. The incidence of idiopathic cataract is highest in developing countries and studies have discovered that low birth weight is a risk factor in the development of idiopathic childhood cataract. As low birth weight is a reflection of poor foetal growth, it is possible that maternal malnutrition, which is endemic in some developing countries, results in the altered physiology of the foetal lens. We have conducted a review of the literature that provides evidence for a link between maternal malnutrition, low birth weight and the development of childhood cataract. Using our accumulated knowledge on the pathways that deliver nutrients to the adult lens, we propose a cellular mechanism, by which oxidative stress caused by maternal malnutrition affects the development of antioxidant defence pathways in the embryonic lens, leading to an accelerated onset of nuclear cataract in childhood. © 2013 The Authors. Clinical and Experimental Optometry © 2013 Optometrists Association Australia.

Identification of a novel missense mutation of MAF in a Japanese family with congenital cataract by whole exome sequencing: a clinical report and review of literature.

PubMed

Narumi, Yoko; Nishina, Sachiko; Tokimitsu, Motoharu; Aoki, Yoko; Kosaki, Rika; Wakui, Keiko; Azuma, Noriyuki; Murata, Toshinori; Takada, Fumio; Fukushima, Yoshimitsu; Kosho, Tomoki

2014-05-01

Congenital cataracts are the most important cause of severe visual impairment in infants. Genetic factors contribute to the disease development and 29 genes are known to cause congenital cataracts. Identifying the genetic cause of congenital cataracts can be difficult because of genetic heterogeneity. V-maf avian musculoaponeurotic fibrosarcoma oncogene homolog (MAF) encodes a basic region/leucine zipper transcription factor that plays a key role as a regulator of embryonic lens fiber cell development. MAF mutations have been reported to cause juvenile-onset pulverulent cataract, microcornea, iris coloboma, and other anterior segment dysgenesis. We report on six patients in a family who have congenital cataracts were identified MAF mutation by whole exome sequencing (WES). The heterozygous MAF mutation Q303L detected in the present family occurs in a well conserved glutamine residue at the basic region of the DNA-binding domain. All affected members showed congenital cataracts. Three of the six members showed microcornea and one showed iris coloboma. Congenital cataracts with MAF mutation exhibited phenotypically variable cataracts within the family. Review of the patients with MAF mutations supports the notion that congenital cataracts caused by MAF mutations could be accompanied by microcornea and/or iris coloboma. WES is a useful tool for detecting disease-causing mutations in patients with genetically heterogeneous conditions. © 2014 Wiley Periodicals, Inc.

Effects of N-acetylcysteine and glutathione ethyl ester drops on streptozotocin-induced diabetic cataract in rats.

PubMed

Zhang, Shu; Chai, Fei-Yan; Yan, Hong; Guo, Yong; Harding, J J

2008-05-12

To evaluate the effect of N-acetylcysteine (NAC) and glutathione ethyl ester (GSH-EE) eye drops on the progression of diabetic cataract formation induced by streptozotocin (STZ). One hundred and thirty Sprague-Dawley (SD) rats were selected, and diabetes was induced by streptozotocin (65 mg/kg bodyweight) in a single intraperitoneal injection. The control group (group I) received only vehicle. Then, 78 rats with random blood glucose above 14 mmol/l were divided into four groups (group II-V). The drug-treated rats received NAC and GSH-EE eye drops five days before STZ injection. Group I and V animals received sodium phosphate buffer drops (pH 7.4), and those in groups II, III, and IV received 0.01% NAC, 0.05% NAC, and 0.1% GSH-EE drops, respectively. Lens transparency was monitored with a slit lamp biomicroscope and classified into six stages. At the end of four weeks, eight weeks, and 13 weeks, animals were killed and components involved in the pathogenesis of diabetic cataract including thiols (from glutathione and protein), glutathione reductase (GR), catalase (CAT), and glycated proteins were investigated in the lens extracts. Blood glucose, urine glucose, and bodyweight were also determined. The progression in lens opacity induced by diabetes showed a biphasic pattern in which an initial slow increase in the first seven weeks after STZ injection was followed by a rapid increase in the next six weeks. The progression of lens opacity in the treated groups (group II-IV) was slower than that of the untreated group (group V) in the earlier period and especially in the fourth week. There were statistically significant differences between the treated groups and the untreated group (p<0.05). However, these differences became insignificant after the sixth week, and the progression of lens opacification in all diabetic groups became aggravated. The content of thiol (from glutathione and protein), glutathione reductase (GR), and catalase (CAT) were lower in the lens extracts of the diabetic rats four weeks, eight weeks, and 13 weeks after the STZ injection while the levels of thiol and CAT activity were both higher in the treated groups (group II-IV) than in the untreated group (group V) at every stage. However, there was no statistically significant difference (p>0.05). Moreover, the diabetes resulted in an increased level of glycated proteins in both the treated groups and the untreated group, but there was no statistically significant difference between all the diabetic groups (p>0.05). NAC and GSH-EE can slightly inhibit the progression of the diabetic cataract at the earlier stage. They may maintain lens transparency and function by serving as a precursor for glutathione biosynthesis and by protecting sulfhydryl groups from oxidation.

Trends in cataract surgical rate and resource utilisation in Egypt.

PubMed

Elbieh, Islam; Bascaran, Covadonga; Blanchet, Karl; Foster, Allen

2018-06-08

To describe cataract services in Egypt and explore resources and practices in public and private sectors. The study was conducted between June and August 2015. All facilities in the country providing cataract services were contacted to obtain information on surgeries performed in 2014. Hospitals performing eye surgery in Quena, Sharkia, and Fayoum regions were visited and a questionnaire on resources for cataract surgery was completed. Cataract surgery was offered in the public sector by 64 government and 16 university teaching hospitals and in the private sector by 101 hospitals. Over 90% of all facilities in the country contacted participated in the study. In 2014, the national cataract surgical rate (CSR) was 3674 varying in governorates from 7579 in Ismailia to 402 in Suez. The private sector performed 70% of cataract surgeries. Analysis of three regions showed an 11.7% increase in cataract output between 2010 and 2014. The average number of cataract surgeries per unit in 2014 was 2272 in private, 1633 in university, and 824 in government hospitals. Private hospitals had 60% of human resources for eye care. Phacoemulsification was the surgical technique in 85.6% of private, 72.1% of university, and 41% of government hospitals. Reasons explaining the differences in output between public and private sectors were the lack of trainers, supervisors, and incentives. The private sector provides most of the cataract services in Egypt, resulting in inadequate services for the poor. There is a 15-fold variation in CSR between the best and least served regions. The public sector could increase cataract output by improving training, supervision, and incentives.

Grading nuclear, cortical and posterior subcapsular cataracts using an objective scatter index measured with a double-pass system.

PubMed

Vilaseca, Meritxell; Romero, Maria José; Arjona, Montserrat; Luque, Sergio Oscar; Ondategui, Juan Carlos; Salvador, Antoni; Güell, José L; Artal, Pablo; Pujol, Jaume

2012-09-01

To evaluate objectively intraocular scattering in eyes with nuclear, cortical and posterior subcapsular cataracts by means of an objective scatter index (OSI) obtained from double-pass images. To compare the results with those obtained using clinical conventional procedures. In this prospective, observational, cross-sectional, non-consecutive case series study, 188 eyes with cataracts of 136 patients were analysed (123 eyes had nuclear, 41 eyes had cortical and 24 eyes had posterior subcapsular cataracts). The control group consisted of 117 eyes of 68 healthy patients. Patient examination included subjective refraction, best spectacle-corrected visual acuity (BSCVA), cataract grade using the lens opacities classification system III (LOCS III) and OSI. We found a decrease in the BSCVA and an increase in the OSI with increasing cataract grade. Statistically significant differences were observed when the OSI of eyes without cataracts and those with different LOCS III were compared. The comparison between the OSI and LOCS III reported good percentages of agreement regarding the number of eyes classified in equivalent levels: 72.4% (nuclear cataracts), 86.6% (cortical cataracts) and 84.3% (posterior subcapsular cataracts). A non-linear regression model was applied between OSI and BSCVA, which resulted in the following multiple correlation coefficients: r=0.878 (nuclear), r=0.843 (cortical) and r=0.844 (posterior subcapsular). The results of the study showed that OSI is a useful parameter for evaluating large amounts of intraocular scattering that can be used, in combination with other conventional procedures, as a valuable tool in clinical practice to grade cataracts objectively.

Mortality after endophthalmitis following contemporary phacoemulsification cataract surgery.

PubMed

Crosby, Niall; Polkinghorne, Philip J; Kim, Bia; McGhee, Charles; Welch, Sarah; Riley, Andrew

2018-04-24

To determine if endophthalmitis following cataract surgery is linked to increased mortality. Increased mortality has been linked to patients with cataract and cataract surgery. We tested the hypothesis that post-cataract endophthalmitis has a greater risk of death than pseudophakes who do not develop this complication. Case-control study conducted in a tertiary public hospital. The study group comprised 50 consecutive patients with post-cataract endophthalmitis, and these were matched with selected controls. Patients with endophthalmitis following cataract surgery were identified from a prospective electronic surgical database. Subsequently, it was determined if the patient was deceased at the time of sequestration (September 2015), and the date of death was recorded. A previously described population who had undergone cataract surgery in the same facility was selected as a control group, and the population was case-matched in terms age, gender, presence or absence of diabetes and/or hypertension. The median survival rates were determined for the control group and the patients with post-cataract endophthalmitis. Fifty patients were identified as undergoing endophthalmitis post-cataract surgery, and 48 (n = 48) met inclusion criteria (mean age 72 years ±12 SD with 30:18 F:M); 17% were diabetic, and 50% had systemic hypertension. No statistically significant difference in median survival between the study and control cases was identified (100 months (95% confidence interval 86-114) vs. 106 months (95% confidence interval 66-146), respectively, P = 0.756). Post-cataract endophthalmitis was not associated with an increased rate of mortality in this study. © 2018 Royal Australian and New Zealand College of Ophthalmologists.

Radiation effects on late cytopathological parameters in the murine lens relative to particle fluence

NASA Astrophysics Data System (ADS)

Tao, F.; Powers-Risius, P.; Alpen, E. L.; Medvedovsky, C.; David, J.; Worgul, B. V.

1994-10-01

Lenses of mice irradiated with 250 MeV protons, 670 MeV/amu20Ne, 600 MeV/amu 56Fe, 600 MeV/amu 93Nb and 593 MeV/amu 139La ions were evaluated by analyzing cytopathological indicators which have been implicated in the cataractogenic process. The LETs ranged from 0.40 keV/μm to 953 keV/μm and fluences from 1.31 × 103/mm2 to 4.99 × 107/mm2. 60Co γ-rays were used as the reference radiation. The doses ranged from 10 to 40 cGy. The lenses were assessed 64 weeks post irradiation in order to observe the late effects of LET and dose on the target cell population of the lens epithelium. Our study shows that growth dependent pathological changes occur at the cellular level as a function of dose and LET. The shapes of the RBE-LET and RBE-dose curves are consistent with previous work on eye and other biological systems done in both our laboratory and others. The RBEmax's were estimated, for the most radiation cataract related cytological changes, MN frequency and MR disorganization, by calculating the ratio of the initial slopes of dose effect curve for various heavy ions to that of 60Co γ-ray. For each ion studied, the RBEmax derived from micronucleus (MN) frequency is similar to that derived from meridional row (MR) disorganization, suggesting that heavy ions are equally efficient at producing each type of damage. Furthermore, on a per particle basis (particle/cell nucleus), both MN frequency and MR disorganization are LET dependent indicating that these classic precataractogenic indicators are multi-gene effects. Poisson probability analysis of the particle number traversing cell nuclei (average area = 24 μm2)suggested that single nuclear traversals determine these changes. By virtue of their precataractogenic nature the data on these endpoints intimate that radiation cataract may also be the consequence of single hits. In any case, these observations are consistent with the current theory of the mechanism of radiation cataractogenesis, which proposes that genomic damage to the epithelial cells surviving the exposure is responsible for opacification.

Risk of radiation induced cataracts: investigation of radiation exposure to the eye lens during endourologic procedures.

PubMed

Hartmann, Josefin; Distler, Florian A; Baumueller, Martin; Guni, Ewald; Pahernik, Sascha A; Wucherer, Michael

2018-06-14

Due to new radiobiological data, the ICRP recommends a dose limit of 20mSv per year to the eye lens. Therefore, the IAEA International Basic Safety Standard and the EU council directive 2013/59/EURATOM requires a reduction of the annual dose limit from 150mSv to 20mSv. Urologists are exposed to an elevated radiation exposure in the head region during fluoroscopic interventions, due to the commonly used overtable X-ray tubes and the rarely used radiation protection for the head. Aim of the study was to analyze real radiation exposure to the eye lens of the urologist during various interventions during which the patient is in the lithotomy position. The partial body doses (forehead and apron collar) of the urologists and surgical staff were measured over a period of two months. 95 interventions were performed on Uroskop Omnia Max workplaces (Siemens Healthineers, Erlangen, Germany). Interventions were class-divided in less (stage I) and more complex (stage II) interventions. Two dosimeter-types were applied: well-calibrated electronic personal dosimeter EPD Mk2 and self-calibrated TLD-100H (both Thermo Fisher Scientific, Waltham, USA). The radiation exposure parameters were documented using the dose area product (DAP) and the fluoroscopy time (FT). The correlation between DAP and the apron dose of the urologist was in average 0.07µSv per 1µGym². The more experienced urologists yielded a mean DAP of 166µGym² for stage I and 415µGym² for stage II procedures. The interventionist was exposed with 10µSv in mean outside the lead apron collar. The mean dose value of the eye lenses per intervention was ascertained to 20µSv (mean DAP: 233µGym²). The study setup allows a differentiated and time-resolved measurement of the radiation exposure, which was found heterogeneous depending on intervention and surgeon. In this setting, approximately 1000 interventions can be performed until the annual eye lens dose limit is achieved.

Mutations and mechanisms in congenital and age-related cataracts

PubMed Central

Shiels, Alan; Hejtmancik, J. Fielding

2017-01-01

The crystalline lens plays an important role in the refractive vision of vertebrates by facilitating variable fine focusing of light onto the retina. Loss of lens transparency, or cataract, is a frequently acquired cause of visual impairment in adults and may also present during childhood. Genetic studies have identified mutations in over 30 causative genes for congenital or other early-onset forms of cataract as well as several gene variants associated with age-related cataract. However, the pathogenic mechanisms resulting from genetic determinants of cataract are only just beginning to be understood. Here, we briefly summarize current concepts pointing to differences in the molecular mechanisms underlying congenital and age-related forms of cataract. PMID:27334249

Changing trends in barriers to cataract surgery in India.

PubMed

Vaidyanathan, K; Limburg, H; Foster, A; Pandey, R M

1999-01-01

Cataract is a major cause of blindness in Asia. Efforts in India to provide cataract surgical services have had limited success in reaching the cataract-blind population. Earlier studies identified the major barriers to cataract surgery as poverty, lack of transportation or felt need, or sex related; and the critical barriers in rural areas as lack of awareness, difficult access, and cost. Compared with these earlier data, the results of the present study in Karnataka State indicate a shift in the character of the barriers. They now appear to be more related to case selection and service provision. These shifts are analysed and alternative strategies to increase the uptake to cataract surgery are recommended.

Inherited Congenital Cataract: A Guide to Suspect the Genetic Etiology in the Cataract Genesis

PubMed Central

Messina-Baas, Olga; Cuevas-Covarrubias, Sergio A.

2017-01-01

Cataracts are the principal cause of treatable blindness worldwide. Inherited congenital cataract (CC) shows all types of inheritance patterns in a syndromic and nonsyndromic form. There are more than 100 genes associated with cataract with a predominance of autosomal dominant inheritance. A cataract is defined as an opacity of the lens producing a variation of the refractive index of the lens. This variation derives from modifications in the lens structure resulting in light scattering, frequently a consequence of a significant concentration of high-molecular-weight protein aggregates. The aim of this review is to introduce a guide to identify the gene involved in inherited CC. Due to the manifold clinical and genetic heterogeneity, we discarded the cataract phenotype as a cardinal sign; a 4-group classification with the genes implicated in inherited CC is proposed. We consider that this classification will assist in identifying the probable gene involved in inherited CC. PMID:28611546

Cataract surgery in juvenile xanthogranuloma: case report and a brief review of literature.

PubMed

Muralidhar, R; Jain, Ashish; Vijayalakshmi, P; Suparna, G; Santhi, R; Shetty, Shashikanth

2013-11-01

There is limited literature on the management of cataracts in juvenile xanthogranuloma (JXG). A 2-month-old girl presented to us with hyphema, secondary glaucoma OU and skin nodules suggestive of JXG. She developed bilateral cataracts during her follow-up and was treated successfully with cataract surgery and aphakic rehabilitation.

Objective functional visual outcomes of cataract surgery in patients with good preoperative visual acuity

PubMed Central

Zhu, X; Ye, H; He, W; Yang, J; Dai, J; Lu, Y

2017-01-01

Purpose To explore the objective functional visual outcomes of cataract surgery in patients with good preoperative visual acuity. Methods We enrolled 130 cataract patients whose best-corrected visual acuity (BCVA) was 20/40 or better preoperatively. Objective visual functions were evaluated with a KR-1W analyzer before and at 1 month after cataract surgery. Results The nuclear (N), cortical (C), and N+C groups had very high preoperative ocular and internal total high-order aberrations (HOAs), coma, and abnormal spherical aberrations. At 1 month after cataract surgery, in addition to the remarkable increase of both uncorrected visual acuity and BCVA, both ocular and internal HOAs in the three groups decreased significantly after cataract surgery (all P<0.05). Point spread function and modulation transfer functions were also improved significantly in these patients (all P<0.05). Conclusions The objective functional vision of patients with 20/40 or better preoperative BCVA improved significantly after cataract surgery. This finding shows that the arbitrary threshold of BCVA worse than 20/40 in China cannot always be used to determine who will benefit from cataract surgery. PMID:27858933

Surgical, medical and developmental outcomes in patients with Down syndrome and cataracts.

PubMed

Santoro, Stephanie L; Atoum, Dema; Hufnagel, Robert B; Motley, William W

2017-01-01

Individuals with Down syndrome have an increased risk for congenital cataracts, but descriptions of surgical, medical and developmental outcomes are sparse. Retrospective review of medical charts of patients with Down syndrome with visits to Cincinnati Children's Hospital from 1988 to 2013 was performed. A case series of five patients with Down syndrome and cataracts is presented. A total of 47 patients with Down syndrome without cataracts were used as a developmental control. Developmental quotients were compared using an independent-sample, unequal variance t-test. Post-operative cataract complication rates ranged from 20% to 60%. Visual outcomes were varied; significant associations between complication rate and visual outcome were not found. Developmental quotients did not show an association with number of complications, but were lower for children with Down syndrome with cataracts requiring surgery compared to children with Down syndrome without cataracts. In children with Down syndrome and congenital cataract, surgical intervention has risk for post-operative complications. Further investigation is needed to determine if there is an association between surgical complications and visual or developmental outcomes.

Pediatric cataract: challenges and future directions

PubMed Central

Medsinge, Anagha; Nischal, Ken K

2015-01-01

Cataract is a significant cause of visual disability in the pediatric population worldwide and can significantly impact the neurobiological development of a child. Early diagnosis and prompt surgical intervention is critical to prevent irreversible amblyopia. Thorough ocular evaluation, including the onset, duration, and morphology of a cataract, is essential to determine the timing for surgical intervention. Detailed assessment of the general health of the child, preferably in conjunction with a pediatrician, is helpful to rule out any associated systemic condition. Although pediatric cataracts have a diverse etiology, with the majority being idiopathic, genetic counseling and molecular testing should be undertaken with the help of a genetic counselor and/or geneticist in cases of hereditary cataracts. Advancement in surgical techniques and methods of optical rehabilitation has substantially improved the functional and anatomic outcomes of pediatric cataract surgeries in recent years. However, the phenomenon of refractive growth and the process of emmetropization have continued to puzzle pediatric ophthalmologists and highlight the need for future prospective studies. Posterior capsule opacification and secondary glaucoma are still the major postoperative complications necessitating long-term surveillance in children undergoing cataract surgery early in life. Successful management of pediatric cataracts depends on individualized care and experienced teamwork. We reviewed the etiology, preoperative evaluation including biometry, choice of intraocular lens, surgical techniques, and recent developments in the field of childhood cataract. PMID:25609909

Incidence and Characteristics of Cataract Surgery in Poland, during 2010-2015.

PubMed

Nowak, Michał S; Grabska-Liberek, Iwona; Michalska-Małecka, Katarzyna; Grzybowski, Andrzej; Kozioł, Milena; Niemczyk, Wojciech; Więckowska, Barbara; Szaflik, Jacek P

2018-03-02

Background: To assess the incidence and characteristic of cataract surgery in Poland from 2010 to 2015 and to interpret these findings. Patients and methods: Data from all patients who underwent cataract surgery alone or in combined procedures in Poland between January 2010 and December 2015 were evaluated. Patient data were from the national database of hospitalizations maintained by National Health Fund. Data on the population of Poland were obtained from Central Statistical Office of Poland. Results: In total, 1,218,777 cataract extractions (alone or combined with other procedures) were performed in 1,081,345 patients during 2010-2015. Overall, the incidence of cataract surgery increased from 5.22/1000 person-years in 2010 to 6.17/1000 person-years in 2015. Phacoemulsification was performed in 97.46% of cataract extractions, and 3.02% of cataract extractions were combined procedures. The rate of one-day procedures increased from 28.3% in 2010 to 43.1% in 2015. The probability of second-eye surgery 12 months after the first-eye surgery increased from 44% in 2010 to 73% in 2015 (log-rank test p < 0.0001). Conclusion: In Poland, from 2010 to 2015, the total incidence of cataract surgery, the number of people who underwent surgery, and the number of one-day cataract surgeries increased significantly.

Lanosterol reverses protein aggregation in cataracts.

PubMed

Zhao, Ling; Chen, Xiang-Jun; Zhu, Jie; Xi, Yi-Bo; Yang, Xu; Hu, Li-Dan; Ouyang, Hong; Patel, Sherrina H; Jin, Xin; Lin, Danni; Wu, Frances; Flagg, Ken; Cai, Huimin; Li, Gen; Cao, Guiqun; Lin, Ying; Chen, Daniel; Wen, Cindy; Chung, Christopher; Wang, Yandong; Qiu, Austin; Yeh, Emily; Wang, Wenqiu; Hu, Xun; Grob, Seanna; Abagyan, Ruben; Su, Zhiguang; Tjondro, Harry Christianto; Zhao, Xi-Juan; Luo, Hongrong; Hou, Rui; Jefferson, J; Perry, P; Gao, Weiwei; Kozak, Igor; Granet, David; Li, Yingrui; Sun, Xiaodong; Wang, Jun; Zhang, Liangfang; Liu, Yizhi; Yan, Yong-Bin; Zhang, Kang

2015-07-30

The human lens is comprised largely of crystallin proteins assembled into a highly ordered, interactive macro-structure essential for lens transparency and refractive index. Any disruption of intra- or inter-protein interactions will alter this delicate structure, exposing hydrophobic surfaces, with consequent protein aggregation and cataract formation. Cataracts are the most common cause of blindness worldwide, affecting tens of millions of people, and currently the only treatment is surgical removal of cataractous lenses. The precise mechanisms by which lens proteins both prevent aggregation and maintain lens transparency are largely unknown. Lanosterol is an amphipathic molecule enriched in the lens. It is synthesized by lanosterol synthase (LSS) in a key cyclization reaction of a cholesterol synthesis pathway. Here we identify two distinct homozygous LSS missense mutations (W581R and G588S) in two families with extensive congenital cataracts. Both of these mutations affect highly conserved amino acid residues and impair key catalytic functions of LSS. Engineered expression of wild-type, but not mutant, LSS prevents intracellular protein aggregation of various cataract-causing mutant crystallins. Treatment by lanosterol, but not cholesterol, significantly decreased preformed protein aggregates both in vitro and in cell-transfection experiments. We further show that lanosterol treatment could reduce cataract severity and increase transparency in dissected rabbit cataractous lenses in vitro and cataract severity in vivo in dogs. Our study identifies lanosterol as a key molecule in the prevention of lens protein aggregation and points to a novel strategy for cataract prevention and treatment.

Lenticular changes in congenital iridolenticular choroidal coloboma.

PubMed

Mohamed, Ashik; Chaurasia, Sunita; Ramappa, Muralidhar; Sangwan, Virender S; Jalali, Subhadra

2014-10-01

To evaluate the lenticular changes associated with congenital iridolenticular choroidal coloboma. Retrospective, observational case series. setting: Tertiary eye care center in south India. study population: Total of 145 eyes of 98 patients. observation procedure: Medical records of all patients with the diagnosis of congenital iridolenticular choroidal coloboma between January 2011 and December 2012 were reviewed retrospectively for demographic profile, extent of coloboma, and associated lenticular changes. Median age of patients at the time of initial visit was 23 years (interquartile range, 13-38 years). The male-to-female ratio was ∼ 1:1. Forty-eight percent had bilateral involvement. Lens showed cataract changes in 68 eyes (48.9%). The most common type of cataract was nuclear sclerosis, which was noted in 51% of cases. A distinct type of cataract, called "coloboma cataract" (characterized by linear opacity in the region of the coloboma), was observed in 29% of cases. Other associated findings were phacodonesis in 3 eyes, dislocation in 3 eyes, and subluxation in 5 eyes. Disc and/or macular involvement in 57 eyes (39.3%) did not influence the type or density of cataract (P > .05). Congenital iridolenticular choroidal coloboma is associated with early cataractous changes. The most common type of cataract is nuclear sclerosis. The type and density of cataract do not seem to be related to the extent of the choroidal coloboma. We suggest a distinct description with the nomenclature "coloboma cataract" to be considered in the clinical grading of cataracts in patients with this condition. Copyright © 2014 Elsevier Inc. All rights reserved.

Plasma catalase activity and malondialdehyde level in patients with cataract.

PubMed

Ateş, N A; Yildirim, O; Tamer, L; Unlü, A; Ercan, B; Muşlu, N; Kanik, A; Hatungil, R; Atik, U

2004-08-01

Oxidative mechanisms play a major role in the aetiology and pathogenesis of cataract, especially in age-related cataract. Our study aims to investigate systemic oxidant and antioxidant markers in cataract patients. The activity of erythrocyte catalase and the level of malondialdehyde in plasma were measured in 40 patients with cataract and 60 healthy control subjects. The malondialdehyde level, as an index of lipid peroxidation, was determined by thiobarbitüric acid reaction according to Yagi. The determination of catalase activity was measured by a method that was defined by Beutler. Catalase enzyme activity and malondialdehyde level were evaluated to find out whether there was a significant difference in these variables. Analysis of variance was used by forming a general linear model that takes age and gender as the covariate. CAT activity was found to be 13 920.2 +/- 847.9 U/l in cataract patients and 16 061.3 +/- 1126.6 U/l in control subjects. CAT activity in cataract patients was significantly lower than the control subjects (P = 0.008). Plasma MDA level is significantly higher in patients with cataract 4.47 +/- 0.35 nmol/ml compared to the control subjects 2.94 +/- 0.26 nmol/ml (P = 0.0001). There was no significant difference between different cataract subgroups when erythrocyte CAT activities and plasma MDA levels were compared (P = 0.322, 0.062). This study shows that oxidant/antioxidant balances alter in the presence of cataract.

Impact of cataract surgery in reducing visual impairment: a review.

PubMed

Khandekar, Rajiv; Sudhan, Anand; Jain, B K; Deshpande, Madan; Dole, Kuldeep; Shah, Mahul; Shah, Shreya

2015-01-01

The aim was to assess the impact of cataract surgeries in reducing visual disabilities and factors influencing it at three institutes of India. A retrospective chart review was performed in 2013. Data of 4 years were collected on gender, age, residence, presenting a vision in each eye, eye that underwent surgery, type of surgery and the amount the patient paid out of pocket for surgery. Visual impairment was categorized as; absolute blindness (no perception of light); blind (<3/60); severe visual impairment (SVI) (<6/60-3/60); moderate visual impairment (6/18-6/60) and; normal vision (≥6/12). Statistically analysis was performed to evaluate the association between visual disabilities and demographics or other possible barriers. The trend of visual impairment over time was also evaluated. We compared the data of 2011 to data available about cataract cases from institutions between 2002 and 2009. There were 108,238 cataract cases (50.6% were female) that underwent cataract surgery at the three institutions. In 2011, 71,615 (66.2%) cases underwent surgery. There were 45,336 (41.9%) with presenting vision < 3/60 and 75,393 (69.7%) had SVI in the fellow eye. Blindness at presentation for cataract surgery was associated to, male patients, Institution 3 (Dristi Netralaya, Dahod) surgeries after 2009, cataract surgeries without Intra ocular lens implant implantation, and patients paying <25 US $ for surgery. Predictors of SVI at time of cataract surgery were, male, Institution 3 (OM), phaco surgeries, those opting to pay 250 US $ for cataract surgeries. Patients with cataract seek eye care in late stages of visual disability. The goal of improving vision related quality of life for cataract patients during the early stages of visual impairment that is common in industrialized countries seems to be non-attainable in the rural India.

Impact of cataract surgery on vision-related life performances: the usefulness of Real-Life Vision Test for cataract surgery outcomes evaluation

PubMed Central

Ni, W; Li, X; Hou, Z; Zhang, H; Qiu, W; Wang, W

2015-01-01

Purpose Real-Life Vision Test (RLVT) is a newly developed performance-based measures of functional vision. This present study is designed to determine whether it could be a meaningful assessment for cataract surgery outcomes evaluation. Patients and methods Age-related cataract patients (56) who scheduled for bilateral cataract surgery and 44 age-matched controls were evaluated by four types of measurements: (1) demographic, medical, cognitive and depressive evaluation, and the reaction time testing; (2) clinical measures (visual acuity, contrast sensitivity, stereopsis, and color perception); (3) the 25-item National Eye Institute's Visual Functioning Questionnaire (NEI-VFQ); (4) the RLVT. Spearman's coefficients and multiple regression analysis were conducted to investigate the relationship among RLVT, clinical measures, and self-report assessment of visual function. Results The results of RLVT, clinical measures, and NEI-VFQ total scores were improved significantly after cataract surgery. There were no differences between control subjects and post-surgery patients with respect to NEI-VFQ-25 total scores, self-rating depression scale scores and three tasks of RLVT. Change of RLVT was significantly associated with the change of clinical measures in the cataract group. Multiple regression analysis demonstrated that change of distance, intermediate, and near visual acuity, and binocular contrast sensitivity were significant predictors of improvements of RLVT. Conclusions Cataract surgery could improve real-world visual ability effectively for cataract patients. Our study highlights the potential usefulness of RLVT as an adjunct to the current outcomes evaluation system for cataract surgery. The use of RLVT combined with clinical and self-survey methods may be the comprehensive strategy to manifest the impact of cataract surgery on patients' overall vision-related quality of life. PMID:26272444

Older drivers and cataract: driving habits and crash risk.

PubMed

Owsley, C; Stalvey, B; Wells, J; Sloane, M E

1999-04-01

Cataract is a leading cause of vision impairment in older adults, affecting almost half of those over age 75 years. Driving is a highly visual task and, as with other age groups, older adults rely on the personal automobile for travel. The purpose of this study was to examine the role of cataract in driving. Older adults (aged 55-85 years) with cataract (n = 279) and those without cataract (n = 105) who were legally licensed to drive were recruited from eye clinics to participate in a driving habits interview to assess driving status, exposure, difficulty, and "space" (the distance of driving excursions from home base). Crash data over the prior 5 years were procured from state records. Visual functional tests documented the severity of vision impairment. Compared to those without cataract, older drivers with cataract were approximately two times more likely to report reductions in days driven and number of destinations per week, driving slower than the general traffic flow, and preferring someone else to drive. Those with cataract were five times more likely to have received advice about limiting their driving. Those with cataract were four times more likely to report difficulty with challenging driving situations, and those reporting driving difficulty were two times more likely to reduce their driving exposure. Drivers with cataract were 2.5 times more likely to have a history of at-fault crash involvement in the prior 5 years (adjusted for miles driven/week and days driven/week). These associations remained even after adjustments for the confounding effects of advanced age, impaired general health, mental status deficit, or depression. Older drivers with cataract experience a restriction in their driving mobility and a decrease in their safety on the road. These findings serve as a baseline for our ongoing study evaluating whether improvements in vision following cataract surgery expand driving mobility and improve driver safety.

Awareness and eye health-seeking practices for cataract among urban slum population of Delhi: The North India eye disease awareness study.

PubMed

Misra, Vasundhra; Vashist, Praveen; Singh, Senjam Suraj; Malhotra, Sumit; Gupta, Vivek; Dwivedi, S N; Gupta, Sanjeev K

2017-12-01

The objective of the study was to assess the awareness and health-seeking practices related to cataract in urban slums of Delhi. This study design was a population-based cross-sectional study. Participants aged 18-60 years were recruited from randomly selected five slums of South Delhi. They were interviewed using a semi-structured interview schedule on awareness and eye health-seeking practices related to cataract. The practices were recorded if the respondents themselves or any other member of the family was diagnosed with cataract in previous 2 years. A total of 1552 respondents participated in the study, of which, 89.9% had heard of cataract but only (42%) were aware of any symptom of cataract. The common symptoms of cataract reported by the participants were white opacity in eyes (25.9%) and loss of vision (20.6%). Surgery as a treatment of cataract was known to only 559 (40.1%) participants. Awareness about surgery as treatment of cataract was significantly higher among people aged 45-60 years (adjusted odds ratio = 2.89, 95% confidence interval = 2.11-3.97) and in educated people (adjusted OR = 3.69 95% CI = 2.37-5.73). Out of 84 respondents who had been diagnosed with cataract, the health-seeking practices were observed by 70 (83.3%) participants. Among them, 51 (72.9%) had undergone surgery and another 19 (27.1%) had been advised to wait for surgery. Most of the operated patients 48 (94.1%) attended the postoperative follow-up. The study findings suggest the majority of participants have heard of cataract, but there is low awareness of its symptoms and treatment, and good eye health-seeking practices observed for cataract in urban slum population. Gaps in awareness observed can be filled up by implementing proper eye health education programs.

Evaluation of advanced glycation end-products in diabetic and inherited canine cataracts.

PubMed

Bras, I Dineli; Colitz, Carmen M H; Kusewitt, Donna F; Chandler, Heather; Lu, Ping; Gemensky-Metzler, Anne J; Wilkie, David A

2007-02-01

The receptor for advanced glycation end-products (RAGE) increases in the human cataract and should correlate with increased DNA damage and proliferation of lens epithelial cells (LECs). The purpose of this study was to measure and immunolocalize RAGE in normal and cataractous canine LECs, and to determine whether there was a correlation between RAGE and DNA damage (gadd45), cell-cycle regulation (p21), and LEC proliferation (proliferating cell nuclear antigen, PCNA). Thirty-two anterior lens capsules from 22 dogs that underwent cataract surgery and 10 lenses from dogs with normal eyes were evaluated. Eleven of the cataractous lenses were from diabetic patients (n=16), and eleven were from patients with inherited cataracts (n=16). Standard immunohistochemical staining was performed using antibodies against RAGE, gadd45, p21, PCNA, alpha-smooth muscle actin, and TGF-beta. Immunostaining intensity for each antibody was given a score of 0-4+. Standard Western blot analysis on normal and cataractous lens capsules was performed using the same antibodies as in the immunohistochemical staining. Comparisons were also made based on age and sex. Real-time reverse transcriptase-polymerase chain reaction (qRT-PCR) was performed for RAGE. There was an increase in RAGE expression with age in normal LECs, but no significant difference was seen when normal adult LECs were compared to cataractous LECs. The stage of the cataract and the presence of LIU were not associated with a significant increase in RAGE expression. There was no age-dependent difference in the normal lenses for gadd45, p21, or PCNA. Significant up-regulation of p21 (P < 0.05) and PCNA (P < 0.05) was seen in diabetic cataracts compared to inherited cataracts. RAGE and PCNA expression did not increase with cataractogenesis, possibly due to overexpression associated with normal aging and constant exposure to oxidative stress from sunlight-related ultraviolet irradiation, respectively. However, p21 and PCNA increased in diabetic cataractogenesis suggesting cell cycle and proliferation dysregulation. This may be related to the rapid onset in this type of cataract compared with the more chronic and slower-to-develop inherited cataracts.

Association of Sex With the Global Burden of Cataract.

PubMed

Lou, Lixia; Ye, Xin; Xu, Peifang; Wang, Jingyi; Xu, Yufeng; Jin, Kai; Ye, Juan

2018-02-01

Eye disease burden could help guide health policy making. Differences in cataract burden by sex is a major concern of reducing avoidable blindness caused by cataract. To investigate the association of sex with the global burden of cataract by year, age, and socioeconomic status using disability-adjusted life-years (DALYs). This international, comparative burden-of-disease study extracted the global, regional, and national sex-specific DALY numbers, crude DALY rates, and age-standardized DALY rates caused by cataract by year and age from the Global Burden of Disease Study 2015. The DALY data were collected from January 1, 1990, through December 31, 2015, for ever 5 years. The human development index (HDI) in 2015 was extracted as an indicator of national socioeconomic status from the Human Development Report. Comparisons of sex-specific DALY estimates due to cataract by year, age, and socioeconomic status at the global level. Paired Wilcoxon signed rank test, Pearson correlation, and linear regression analyses were performed to evaluate the socioeconomic-associated sex differences in cataract burden. Differences in rates of cataract by sex were similar between 1990 and 2015, with age-standardized DALY rates of 54.5 among men vs 65.0 among women in 1990 and 52.3 among men vs 67.0 among women in 2015. Women had higher rates than men of the same age, and sexual differences increased with age. Paired Wilcoxon signed rank test revealed that age-standardized DALY rates among women were higher than those among men for each HDI-based country group (z range, -4.236 to -6.093; P < .001). The difference (female minus male) in age-standardized DALY rates (r = -0.610 [P < .001]; standardized β = -0.610 [P < .001]) and the female to male age-standardized DALY rate ratios (r = -0.180 [P = .02]; standardized β = -0.180 [P = .02]) were inversely correlated with HDI. Although global cataract health care is progressing, sexual differences in cataract burden showed little improvement in the past few decades. Worldwide, women have a higher cataract burden than men. Older age and lower socioeconomic status are associated with greater differences in rates of cataract by sex. Our findings may enhance public awareness of sexual differences in global cataract burden and emphasize the importance of making sex-sensitive health policy to manage global vision loss caused by cataract.

Changing patterns of cataract services in North-West Nigeria: 2005–2016

PubMed Central

Muhammad, Nasiru; Adamu, Mohammed Dantani; Caleb, Mpyet; Maishanu, Nuhu Mohammed; Jabo, Aliyu Mohammed; Rabiu, Muhammad Mansur; Bascaran, Covadonga; Isiyaku, Sunday

2017-01-01

Purpose This study was conducted to assess the impact of the eye care programme on cataract blindness and cataract surgical services in Sokoto, Nigeria over a 12 year period 2005–2016. Methods Data from the 2005 population based cross-sectional study of blindness in Sokoto state was re-analysed to obtain baseline estimates of the prevalence of cataract blindness and cataract surgical coverage for persons 50 years and over in Wurno health zone. A population based survey of a representative sample of persons 50 years and over in Wurno health zone was conducted in July 2016. Data on eye health workforce, infrastructure and cataract surgical services between 2005 and 2016 were analysed from relevant documents. Results In 2005 the unadjusted prevalence of bilateral cataract blindness (<3/60) in people 50 years and over in Wurno health zone was 5.6% (95% CI: 3.1, 10.1). By 2016 this had fallen to 2.1% (95% CI 1.5%, 2.7%), with the age-sex adjusted prevalence being 1.9% (95% CI 1.3%, 2.5%). The CSC for persons with visual acuity <3/60, <6/60, <6/18 for Wurno health zone was 9.1%, 7.1% and 5.5% respectively in 2005 and this had increased to 67.3%, 62.1% and 34.7% respectively in 2016. The CSR in Sokoto state increased from 272 (1005 operations) in 2006, to 596 (2799 operations) in 2014. In the 2005 survey, couching (a procedure used by traditional practitioners to dislocate the lens into the vitreous cavity) accounted for 87.5% of all cataract interventions, compared to 45.8% in the 2016 survey participants. In 2016 18% of eyes having a cataract operation with IOL implantation had a presenting visual acuity of <6/60 (poor outcome) with the main causes being postoperative complications (53%) and uncorrected refractive error (29%). Conclusion Between 2005 and 2016 there was a doubling in cataract surgical rate, a 7 times increase in cataract surgical coverage (<3/60), and a decrease in cataract blindness and the proportion of eyes being couched. However, there remains a high prevalence of un-operated cataract in 2016 indicating a need to further improve access to affordable and good quality cataract surgical services. PMID:28817733

Association of Cataract Surgery With Mortality in Older Women: Findings from the Women's Health Initiative.

PubMed

Tseng, Victoria L; Chlebowski, Rowan T; Yu, Fei; Cauley, Jane A; Li, Wenjun; Thomas, Fridtjof; Virnig, Beth A; Coleman, Anne L

2018-01-01

Previous studies have suggested an association between cataract surgery and decreased risk for all-cause mortality potentially through a mechanism of improved health status and functional independence, but the association between cataract surgery and cause-specific mortality has not been previously studied and is not well understood. To examine the association between cataract surgery and total and cause-specific mortality in older women with cataract. This prospective cohort study included nationwide data collected from the Women's Health Initiative (WHI) clinical trial and observational study linked with the Medicare claims database. Participants in the present study were 65 years or older with a diagnosis of cataract in the linked Medicare claims database. The WHI data were collected from January 1, 1993, through December 31, 2015. Data were analyzed for the present study from July 1, 2014, through September 1, 2017. Cataract surgery as determined by Medicare claims codes. The outcomes of interest included all-cause mortality and mortality attributed to vascular, cancer, accidental, neurologic, pulmonary, and infectious causes. Mortality rates were compared by cataract surgery status using the log-rank test and Cox proportional hazards regression models adjusting for demographics, systemic and ocular comorbidities, smoking, alcohol use, body mass index, and physical activity. A total of 74 044 women with cataract in the WHI included 41 735 who underwent cataract surgery. Mean (SD) age was 70.5 (4.6) years; the most common ethnicity was white (64 430 [87.0%]), followed by black (5293 [7.1%]) and Hispanic (1723 [2.3%]). The mortality rate was 2.56 per 100 person-years in both groups. In covariate-adjusted Cox models, cataract surgery was associated with lower all-cause mortality (adjusted hazards ratio [AHR], 0.40; 95% CI, 0.39-0.42) as well as lower mortality specific to vascular (AHR, 0.42; 95% CI, 0.39-0.46), cancer (AHR, 0.31; 95% CI, 0.29-0.34), accidental (AHR, 0.44; 95% CI, 0.33-0.58), neurologic (AHR, 0.43; 95% CI, 0.36-0.53), pulmonary (AHR, 0.63; 95% CI, 0.52-0.78), and infectious (AHR, 0.44; 95% CI, 0.36-0.54) diseases. In older women with cataract in the WHI, cataract surgery is associated with lower risk for total and cause-specific mortality, although whether this association is explained by the intervention of cataract surgery is unclear. Further study of the interplay of cataract surgery, systemic disease, and disease-related mortality would be informative for improved patient care.

The Association of Outdoor Activity and Age-Related Cataract in a Rural Population of Taizhou Eye Study: Phase 1 Report

PubMed Central

Ye, Xiaofang; Wang, Xiaofeng; Cai, Lei; Xu, Jianming; Lu, Yi

2015-01-01

Purpose To study the relationship between outdoor activity and risk of age-related cataract (ARC) in a rural population of Taizhou Eye Study (phrase 1 report). Method A population-based, cross-sectional study of 2006 eligible rural adults (≥45 years old) from Taizhou Eye Study was conducted from Jul. to Sep. 2012. Participants underwent detailed ophthalmologic examinations including uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), intraocular pressure (IOP), slit lamp and fundus examinations as well as questionnaires about previous outdoor activity and sunlight protection methods. ARC was recorded by LOCSⅢ classification system. The prevalence of cortical, nuclear and posterior subcapsular cataract were assessed separately for the risk factors and its association with outdoor activity. Results Of all 2006 eligible participants, 883 (44.0%) adults were diagnosed with ARC. The prevalence rates of cortical, nuclear and posterior subcapsular cataract per person were 41.4%, 30.4% and 1.5%, respectively. Women had a higher tendency of nuclear and cortical cataract than men (OR = 1.559, 95% CI 1.204–2.019 and OR = 1.862, 95% CI 1.456–2.380, respectively). Adults with high myopia had a higher prevalence of nuclear cataract than adults without that (OR = 2.528, 95% CI 1.055–6.062). Multivariable logistic regression revealed that age was risk factor of nuclear (OR = 1.190, 95% CI 1.167–1.213) and cortical (OR = 1.203, 95% CI 1.181–1.226) cataract; eyes with fundus diseases was risk factor of posterior subcapsular cataract (OR = 6.529, 95% CI 2.512–16.970). Outdoor activity was an independent risk factor of cortical cataract (OR = 1.043, 95% CI 1.004–1.083). The risk of cortical cataract increased 4.3% (95% CI 0.4%-8.3%) when outdoor activity time increased every one hour. Furthermore, the risk of cortical cataract increased 1.1% (95% CI 0.1%-2.0%) when cumulative UV-B exposure time increased every one year. Conclusion Outdoor activity was an independent risk factor for cortical cataract, but was not risk factor for nuclear and posterior subcapsular cataract. The risk of cortical cataract increased 4.3% when outdoor activity time increased every one hour. In addition, the risk of cortical cataract increased 1.1% (95% CI 0.1%-2.0%) when cumulative UV-B exposure time increased every one year. PMID:26284359

One-shot LC-MS/MS analysis of post-translational modifications including oxidation and deamidation of rat lens α- and β-crystallins induced by γ-irradiation.

PubMed

Kim, Ingu; Saito, Takeshi; Fujii, Norihiko; Kanamoto, Takashi; Fujii, Noriko

2016-12-01

The eye lens is a transparent organ that functions to focus light and images on the retina. The transparency and high refraction of the lens are maintained by the function of α-, β-, and γ-crystallins. These long-lived proteins are subject to various post-translational modifications, such as oxidation, deamidation, truncation and isomerization, which occur gradually during the aging process. Such modifications, which are generated by UV light and oxidative stress, decrease crystallin solubility and lens transparency, and ultimately lead to the development of age-related cataracts. Here, we irradiated young rat lenses with γ-rays (5-500 Gy) and extracted the water-soluble (WS) and water-insoluble (WI) protein fractions. The WS and WI lens proteins were digested with trypsin, and the resulting peptides were analyzed by one-shot LC-MS/MS to determine the specific sites of oxidation of methionine and tryptophan, deamidation sites of asparagine and glutamine, and isomerization of aspartyl in rat α- and β-crystallins in the WS and WI fractions. Oxidation and deamidation occurred in several crystallins after irradiation at more than, respectively, 50 and 5 Gy; however, isomerization did not occur in any crystallin even after exposure to 500 Gy of irradiation. The number of oxidation and deamidation sites was much higher in the WI than in the WS fraction. Furthermore, the oxidation and deamidation sites in rat crystallins resemble those reported in crystallins from human age-related cataracts. Thus, this study on post-translational modifications of crystallins induced by ionizing irradiation may provide useful information relevant to the formation of human age-related cataracts.

Neurological and developmental findings in children with cataracts.

PubMed

Pike, M G; Jan, J E; Wong, P K

1989-06-01

Ninety-seven children who were born between 1954 and 1986 and presented to the Visually Impaired Program of British Columbia's Children's Hospital, Vancouver, Canada, with a primary ophthalmologic diagnosis of cataracts, were assessed neurologically, ophthalmologically, audiologically, and developmentally. Causal factors included prenatal infection (35 cases), hereditary cataracts (22 cases), various syndromes and metabolic disorders (9 cases), trauma (1 case), and unknown (30 cases). Ninety children were diagnosed to have congenital cataracts while 7 acquired them. Findings indicated that prenatal infection continues to be a cause of infantile cataracts, despite rubella immunization; that prematurity is not, as has been stated in the past, a cause of infantile cataract; and that careful neurological, audiological, and developmental examination is vital in the assessment of likely causes of this condition.

Vector Analysis of Corneal Astigmatism After Combined Femtosecond-Assisted Phacoemulsification and Arcuate Keratotomy.

PubMed

Chan, Tommy C Y; Cheng, George P M; Wang, Zheng; Tham, Clement C Y; Woo, Victor C P; Jhanji, Vishal

2015-08-01

To evaluate the outcomes of femtosecond-assisted arcuate keratotomy combined with cataract surgery in eyes with low to moderate corneal astigmatism. Retrospective, interventional case series. This study included patients who underwent combined femtosecond-assisted phacoemulsification and arcuate keratotomy between March 2013 and August 2013. Keratometric astigmatism was evaluated before and 2 months after the surgery. Vector analysis of the astigmatic changes was performed using the Alpins method. Overall, 54 eyes of 54 patients (18 male and 36 female; mean age, 68.8 ± 11.4 years) were included. The mean preoperative (target-induced astigmatism) and postoperative astigmatism was 1.33 ± 0.57 diopters (D) and 0.87 ± 0.56 D, respectively (P < .001). The magnitude of error (difference between surgically induced and target-induced astigmatism) (-0.13 ± 0.68 D), as well as the correction index (ratio of surgically induced and target-induced astigmatism) (0.86 ± 0.52), demonstrated slight undercorrection. The angle of error was very close to 0, indicating no significant systematic error of misaligned treatment. However, the absolute angle of error showed a less favorable range (17.5 ± 19.2 degrees), suggesting variable factors such as healing or alignment at an individual level. There were no intraoperative or postoperative complications. Combined phacoemulsification with arcuate keratotomy using femtosecond laser appears to be a relatively easy and safe means for management of low to moderate corneal astigmatism in cataract surgery candidates. Misalignment at an individual level can reduce its effectiveness. This issue remains to be elucidated in future studies. Copyright © 2015 Elsevier Inc. All rights reserved.

Assessment of Levels of Ultraviolet A Light Protection in Automobile Windshields and Side Windows.

PubMed

Boxer Wachler, Brian S

2016-07-01

Ultraviolet A (UV-A) light is associated with the risks of cataract and skin cancer. To assess the level of UV-A light protection in the front windshields and side windows of automobiles. In this cross-sectional study, 29 automobiles from 15 automobile manufacturers were analyzed. The outside ambient UV-A radiation, along with UV-A radiation behind the front windshield and behind the driver's side window of all automobiles, was measured. The years of the automobiles ranged from 1990 to 2014, with an average year of 2010. The automobile dealerships were located in Los Angeles, California. Amount of UV-A blockage from windshields and side windows. The average percentage of front-windshield UV-A blockage was 96% (range, 95%-98% [95% CI, 95.7%-96.3%]) and was higher than the average percentage of side-window blockage, which was 71% (range, 44%-96% [95% CI, 66.4%-75.6%]). The difference between these average percentages is 25% (95% CI, 21%-30% [P < .001]). A high level of side-window UV-A blockage (>90%) was found in 4 of 29 automobiles (13.8%). The level of front-windshield UV-A protection was consistently high among automobiles. The level of side-window UV-A protection was lower and highly variable. These results may in part explain the reported increased rates of cataract in left eyes and left-sided facial skin cancer. Automakers may wish to consider increasing the degree of UV-A protection in the side windows of automobiles.

[Deceleration of cataract development in rats under the action of N-acetylcarnosine and D-pantethine mixture].

PubMed

Avetisov, S É; Sheremet, N L; Muranov, K O; Polianskiĭ, N B; Polunin, G S; Ostrovskiĭ, M A

2014-01-01

The effect of a mixture of N-acetylcarnosine and D-pantethine (1 : 1, m/m) on UV-A induced cataract in rats was studied. It is shown that instillation of a 5% mixture into the eyes or intraperitoneal injections (25 or 150 mg/kg) inhibit the formation of cataracts, starting from 82nd day of the experiment (p < 0.03), after which the protective effect of the mixture significantly increases (p = 0.0003). UV-A irradiation significantly (p < 0.01) increased the content of water-insoluble proteins in the lens. The use of the mixture of N-Acetylcarnosine and D-pantethine prevented (p < 0.001) an increase in the content of water-insoluble proteins caused by UV-A irradiation. Gel permeation chromatography data showed that, in the control group, water insoluble proteins consist of 3 fractions (40 kDa, 100 - 200 kDa, and1000 kDa). UV-A irradiation reduced the amount of protein in fraction 1 and increases the amount of protein in the fractions 2 and 3. The use of the mixture of N-acetylcarnosine and D-pantethine reduced the effects of UV-A light. The authors attribute the effect of the N-acetylcarnosine and D-pantethine mixture to their chaperone-like properties.

Whole Exome Sequencing in Dominant Cataract Identifies a New Causative Factor, CRYBA2, and a Variety of Novel Alleles in Known Genes

PubMed Central

Reis, Linda M.; Tyler, Rebecca C.; Muheisen, Sanaa; Raggio, Victor; Salviati, Leonardo; Han, Dennis P.; Costakos, Deborah; Yonath, Hagith; Hall, Sarah; Power, Patricia; Semina, Elena V.

2013-01-01

Pediatric cataracts are observed in 1–15 per 10,000 births with 10–25% of cases attributed to genetic causes; autosomal dominant inheritance is the most commonly observed pattern. Since the specific cataract phenotype is not sufficient to predict which gene is mutated, whole exome sequencing (WES) was utilized to concurrently screen all known cataract genes and to examine novel candidate factors for a disease-causing mutation in probands from 23 pedigrees affected with familial dominant cataract. Review of WES data for 36 known cataract genes identified causative mutations in nine pedigrees (39%) in CRYAA, CRYBB1, CRYBB3, CRYGC (2), CRYGD, GJA8 (2), and MIP and an additional likely causative mutation in EYA1; the CRYBB3 mutation represents the first dominant allele in this gene and demonstrates incomplete penetrance. Examination of crystallin genes not yet linked to human disease identified a novel cataract gene, CRYBA2, a member of the βγ-crystallin superfamily. The p.(Val50Met) mutation in CRYBA2 cosegregated with disease phenotype in a four-generation pedigree with autosomal dominant congenital cataracts with incomplete penetrance. Expression studies detected cryba2 transcripts during early lens development in zebrafish, supporting its role in congenital disease. Our data highlight the extreme genetic heterogeneity of dominant cataract as the eleven causative/likely causative mutations affected nine different genes and the majority of mutant alleles were novel. Furthermore, these data suggest that less than half of dominant cataract can be explained by mutations in currently known genes. PMID:23508780

Effect of cataract surgery on retinal nerve fiber layer thickness parameters using scanning laser polarimetry (GDxVCC).

PubMed

Dada, Tanuj; Behera, Geeta; Agarwal, Anand; Kumar, Sanjeev; Sihota, Ramanjit; Panda, Anita

2010-01-01

To study the effect of cataract extraction on the retinal nerve fiber layer (RNFL) thickness, and assessment by scanning laser polarimetry (SLP), with variable corneal compensation (GDx VCC), at the glaucoma service of a tertiary care center in North India. Thirty-two eyes of 32 subjects were enrolled in the study. The subjects underwent RNFL analysis by SLP (GDx VCC) before undergoing phacoemulsification cataract extraction with intraocular lens (IOL) implantation (Acrysof SA 60 AT) four weeks following cataract surgery. The RNFL thickness parameters evaluated both before and after surgery included temporal, superior, nasal, inferior, temporal (TSNIT) average, superior average, inferior average, and nerve fiber index (NFI). The mean age of subjects was 57.6 +/- 11.7 years (18 males, 14 females). Mean TSNIT average thickness (microm) pre- and post-cataract surgery was 49.2 +/- 14.1 and 56.5 +/- 7.6 ( P = 0.001). There was a statistically significant increase in RNFL thickness parameters (TSNIT average, superior average, and inferior average) and decrease in NFI post-cataract surgery as compared to the baseline values. Mean NFI pre- and post-cataract surgery was 41.3 +/- 15.3 and 21.6 +/- 11.8 ( P = 0.001). Measurement of RNFL thickness parameters by scanning laser polarimetry is significantly altered following cataract surgery. Post the cataract surgery, a new baseline needs to be established for assessing the longitudinal follow-up of a glaucoma patient. The presence of cataract may lead to an underestimation of the RNFL thickness, and this should be taken into account when analyzing progression in a glaucoma patient.

Unfolded protein response activation in cataracts.

PubMed

Torres-Bernal, Beatriz E; Torres-Bernal, Luis Fernando; Gutiérrez-Campos, Rafael R; Kershenobich Stalnikowitz, David D; Barba-Gallardo, Luis Fernando; Chayet, Arturo A; Ventura-Juárez, Javier

2014-10-01

To analyze the expression of 78 kDa glucose-regulated protein (GRP78) and activating transcription factor 6 (ATF6), 2 factors in the unfolded protein response (UPR), in age-related and diabetes-associated cataract. Universidad Autónoma de Aguascalientes, Aguascalientes, México. Experimental study. The qualitative and quantitative expression of GRP78 and ATF6 were measured in surgical samples from 11 senile cataracts, 9 diabetic-associated cataracts, and 3 normal lenses. Both proteins were detected by immunofluorescence and immunogold-conjugated antibodies. Quantitative morphometry was used to analyze the differences in GRP78 and ATF6 between samples. The Mann-Whitney test was used for statistical analysis. Scanning electron microscopy showed the characteristic organization of fibers in normal lenses with regular alignment and interdigitation between them. On the other hand, lenses from eyes with senile or diabetic cataract showed the same pattern of misalignment and disorganization of the fibers. Both proteins were detected through immunofluorescence in senile and diabetic cataracts, but not in normal lenses. Immunogold-conjugated antibodies and transmission electron microscopy showed that GRP78 and ATF6 grains were 30% higher and 35% higher, respectively, in diabetic cataracts than in senile cataracts (P<.05). These data show for the first time in humans that GRP78 and ATF6 are present in lens fibers of senile cataracts and diabetic cataracts, establishing that the UPR may be important in the process of cataractogenesis. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2014 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Prevalence of pterygium and cataract in indigenous populations of the Brazilian Amazon rain forest.

PubMed

Paula, J S; Thorn, F; Cruz, A A V

2006-05-01

To compare the prevalence of pterygium and cataract in four indigenous populations of the Brazilian Amazonian rain forest (Arawak, Tukano, Maku, and Yanomami) with different ethnic and social behaviour backgrounds. A cross-sectional pterygium and cataract survey was performed in 624 adult Indians of the Brazilian rain forest belonging to four different ethnic groups. The Indians were classified according to their social behaviour in two groups: Arawak and Tukano (group 1) and Maku and Yanomami (group 2). Slit-lamp biomicroscopy was employed to examine the entire sample. All subjects were classified as 1 or 0 according to the presence or absence pterygium and cataract. Sex and age were also recorded. chi(2)-tests revealed that the prevalence of pterygium and cataract differed significantly between groups 1 and 2. For pterygia: 36.6% (97/265) and 5.0% (18/359), respectively (chi(2)=101.2, P<0.0001), and for cataracts: 24.5% (65/265) and 13.7% (49/359) respectively (chi(2)=12.09, P=0.0005). Gender was not associated with pterygium (P=0.1326) and cataract (P=0.2263) in both groups. Elderly subjects showed a significantly higher prevalence of cataract (P<0.0001). The prevalence of pterygia did not increase with age (P=0.8079) in both groups. Indians of group 1 have higher prevalence of pterygia and cataract than Indians of group 2. Social behaviour, especially the rate of sun exposure, appears to be the main factor for the different rates of pterygium and cataract displayed by these indigenous people of the Brazilian rain forest.

The Comparison between Torsional and Conventional Mode Phacoemulsification in Moderate and Hard Cataracts

PubMed Central

Kim, Dong-Hyun; Wee, Won-Ryang; Lee, Jin-Hak

2010-01-01

Purpose To compare the intraoperative performances and postoperative outcomes of cataract surgery performed with longitudinal phacoemulsification and torsional phacoemulsification in moderate and hard cataracts. Methods Of 85 patients who had senile cataracts, 102 eyes were operated on using the Infiniti Vision System. Preoperative examinations (slit lamp examination, mean central corneal thickness, and central endothelial cell counts) were performed for each patient. Cataracts were subdivided into moderate and hard, according to the Lens Opacities Classification System III grading of nucleus opalescence (NO). Eyes in each cataract group were randomly assigned to conventional and torsional phaco-mode. Intraoperative parameters, including ultrasound time (UST), cumulative dissipated energy (CDE), and the balanced salt solution plus (BSSP) volume utilized were evaluated. Best corrected visual acuity (BCVA) was checked on postoperative day 30; mean central corneal thickness and central endothelial cell counts were investigated on postoperative days 7 and 30. Results Preoperative BCVA and mean grading of NO showed no difference in both groups. Preoperative endothelial cell count and central corneal thickness also showed no significant difference in both groups. In the moderate cataract group, the CDE, UST, and BSSP volume were significantly lower in the torsional mode than the longitudinal mode, but they did not show any difference in the hard cataract group. Torsional group showed less endothelial cell loss and central corneal thickening at postoperative day seven in moderate cataracts but showed no significant differences, as compared with the longitudinal group, by postoperative day 30. Conclusions Torsional phacoemulsification showed superior efficiency for moderate cataracts, as compared with longitudinal phacoemulsification, in the early postoperative stage. PMID:21165231

The comparison between torsional and conventional mode phacoemulsification in moderate and hard cataracts.

PubMed

Kim, Dong-Hyun; Wee, Won-Ryang; Lee, Jin-Hak; Kim, Mee-Kum

2010-12-01

To compare the intraoperative performances and postoperative outcomes of cataract surgery performed with longitudinal phacoemulsification and torsional phacoemulsification in moderate and hard cataracts. Of 85 patients who had senile cataracts, 102 eyes were operated on using the Infiniti Vision System. Preoperative examinations (slit lamp examination, mean central corneal thickness, and central endothelial cell counts) were performed for each patient. Cataracts were subdivided into moderate and hard, according to the Lens Opacities Classification System III grading of nucleus opalescence (NO). Eyes in each cataract group were randomly assigned to conventional and torsional phaco-mode. Intraoperative parameters, including ultrasound time (UST), cumulative dissipated energy (CDE), and the balanced salt solution plus (BSSP) volume utilized were evaluated. Best corrected visual acuity (BCVA) was checked on postoperative day 30; mean central corneal thickness and central endothelial cell counts were investigated on postoperative days 7 and 30. Preoperative BCVA and mean grading of NO showed no difference in both groups. Preoperative endothelial cell count and central corneal thickness also showed no significant difference in both groups. In the moderate cataract group, the CDE, UST, and BSSP volume were significantly lower in the torsional mode than the longitudinal mode, but they did not show any difference in the hard cataract group. Torsional group showed less endothelial cell loss and central corneal thickening at postoperative day seven in moderate cataracts but showed no significant differences, as compared with the longitudinal group, by postoperative day 30. Torsional phacoemulsification showed superior efficiency for moderate cataracts, as compared with longitudinal phacoemulsification, in the early postoperative stage.

Prevalence and vision-related outcomes of cataract surgery in Gujarat, India.

PubMed

Murthy, Gudlavalleti V S; Vashist, Praveen; John, Neena; Pokharel, Gopal; Ellwein, Leon B

2009-01-01

Investigate the prevalence and vision-related outcomes of cataract surgery in an area of high cataract surgical rate. Cluster sampling was used in randomly selecting individuals > or = 50 years of age in 2007. Participants were queried regarding year and place of previous cataract surgery. Cataract surgical procedures and evidence of surgical complications were recorded. The principal cause was identified for eyes presenting with visual acuity (VA) < or = 20/40. A total of 4,738 persons were examined and 834 (17.6%) had cataract surgery. Intra-ocular lenses (IOLs) were used in 84.1% of the 1,299 cataract-operated eyes, with more than half of these having manual small incision surgery. Surgical coverage among the cataract blind (visual acuity [VA] < 20/200) was estimated as 72.2%. Coverage was associated with older age, literacy, and urban residence; gender was not significant. Among cataract-operated eyes, 18.7% presented with VA > or = 20/32 and 18.0% were < 20/200. With best-corrected acuity, the corresponding percentages were 55.7% and 11.0%. Presenting and best-corrected VA > or = 20/63 were associated with young age, literacy, and IOL surgery; urban residence and surgery in non-governmental organizations (NGO)/private facilities were also significant for presenting VA; and recent surgery was significant for best-corrected VA. Refractive error was the main cause of vision impairment/blindness in cataract-operated eyes. Refractive error and posterior capsule opacification, easily treatable causes of visual impairment, are common among the operated. A greater emphasis on the quality of visual acuity outcomes along with sustained efforts to provide access to affordable surgery is needed.

Trends in Medicare Service Volume for Cataract Surgery and the Impact of the Medicare Physician Fee Schedule.

PubMed

Gong, Dan; Jun, Lin; Tsai, James C

2017-08-01

To calculate the associations between Medicare payment and service volume for complex and noncomplex cataract surgeries. The 2005-2009 CMS Part B National Summary Data Files, CMS Part B Carrier Summary Data Files, and the Medicare Physician Fee Schedule. Conducting a retrospective, longitudinal analysis using a fixed-effects model of Medicare Part B carriers representing all 50 states and the District of Columbia from 2005 to 2009, we calculated the Medicare payment-service volume elasticities for noncomplex (CPT 66984) and complex (CPT 66982) cataract surgeries. Service volume data were extracted from the CMS Part B National Summary and Carrier Summary Data Files. Payment data were extracted from the Medicare Physician Fee Schedule. From 2005 to 2009, the proportion of total cataract services billed as complex increased from 3.2 to 6.7 percent. Every 1 percent decrease in Medicare payment was associated with a nonsignificant change in noncomplex cataract service volume (elasticity = 0.15, 95 percent CI [-0.09, 0.38]) but a statistically significant increase in complex cataract service volume (elasticity = -1.12, 95 percent CI [-1.60, -0.63]). Reduced Medicare payment was associated with a significant increase in complex cataract service volume but not in noncomplex cataract service volume, resulting in a shift toward performing a greater proportion of complex cataract surgeries from 2005 to 2009. © Health Research and Educational Trust.

Exploiting ensemble learning for automatic cataract detection and grading.

PubMed

Yang, Ji-Jiang; Li, Jianqiang; Shen, Ruifang; Zeng, Yang; He, Jian; Bi, Jing; Li, Yong; Zhang, Qinyan; Peng, Lihui; Wang, Qing

2016-02-01

Cataract is defined as a lenticular opacity presenting usually with poor visual acuity. It is one of the most common causes of visual impairment worldwide. Early diagnosis demands the expertise of trained healthcare professionals, which may present a barrier to early intervention due to underlying costs. To date, studies reported in the literature utilize a single learning model for retinal image classification in grading cataract severity. We present an ensemble learning based approach as a means to improving diagnostic accuracy. Three independent feature sets, i.e., wavelet-, sketch-, and texture-based features, are extracted from each fundus image. For each feature set, two base learning models, i.e., Support Vector Machine and Back Propagation Neural Network, are built. Then, the ensemble methods, majority voting and stacking, are investigated to combine the multiple base learning models for final fundus image classification. Empirical experiments are conducted for cataract detection (two-class task, i.e., cataract or non-cataractous) and cataract grading (four-class task, i.e., non-cataractous, mild, moderate or severe) tasks. The best performance of the ensemble classifier is 93.2% and 84.5% in terms of the correct classification rates for cataract detection and grading tasks, respectively. The results demonstrate that the ensemble classifier outperforms the single learning model significantly, which also illustrates the effectiveness of the proposed approach. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Relationship between postoperative refractive outcomes and cataract density: multiple regression analysis.

PubMed

Ueda, Tetsuo; Ikeda, Hitoe; Ota, Takeo; Matsuura, Toyoaki; Hara, Yoshiaki

2010-05-01

To evaluate the relationship between cataract density and the deviation from the predicted refraction. Department of Ophthalmology, Nara Medical University, Kashihara, Japan. Axial length (AL) was measured in eyes with mainly nuclear cataract using partial coherence interferometry (IOLMaster). The postoperative AL was measured in pseudophakic mode. The AL difference was calculated by subtracting the postoperative AL from the preoperative AL. Cataract density was measured with the pupil dilated using anterior segment Scheimpflug imaging (EAS-1000). The predicted postoperative refraction was calculated using the SRK/T formula. The subjective refraction 3 months postoperatively was also measured. The mean absolute prediction error (MAE) (mean of absolute difference between predicted postoperative refraction and spherical equivalent of postoperative subjective refraction) was calculated. The relationship between the MAE and cataract density, age, preoperative visual acuity, anterior chamber depth, corneal radius of curvature, and AL difference was evaluated using multiple regression analysis. In the 96 eyes evaluated, the MAE was correlated with cataract density (r = 0.37, P = .001) and the AL difference (r = 0.34, P = .003) but not with the other parameters. The AL difference was correlated with cataract density (r = 0.53, P<.0001). The postoperative refractive outcome was affected by cataract density. This should be taken into consideration in eyes with a higher density cataract. (c) 2010 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

The challenges in improving outcome of cataract surgery in low and middle income countries

PubMed Central

Lindfield, Robert; Vishwanath, Kalluru; Ngounou, Faustin; Khanna, Rohit C

2012-01-01

Cataract is the leading cause of blindness globally and surgery is the only known measure to deal with it effectively. Providing high quality cataract surgical services is critical if patients with cataract are to have their sight restored. A key focus of surgery is the outcome of the procedure. In cataract surgery this is measured predominantly, using visual acuity. Population- and hospital-based studies have revealed that the visual outcome of cataract surgery in many low and middle income settings is frequently sub-optimal, often failing to reach the recommended standards set by the World Health Organization (WHO). Another way of measuring outcome of cataract surgery is to ask patients for their views on whether surgery has changed the functioning of their eyes and their quality of life. There are different tools available to capture patient views and now, these patient-reported outcomes are becoming more widely used. This paper discusses the visual outcome of cataract surgery and frames the outcome of surgery within the context of the surgical service, suggesting that the process and outcome of care cannot be separated. It also discusses the components of patient-reported outcome tools and describes some available tools in more detail. Finally, it describes a hierarchy of challenges that need to be addressed before a high quality cataract surgical service can be achieved. PMID:22944761

Operating Room Performance Improves after Proficiency-Based Virtual Reality Cataract Surgery Training.

PubMed

Thomsen, Ann Sofia Skou; Bach-Holm, Daniella; Kjærbo, Hadi; Højgaard-Olsen, Klavs; Subhi, Yousif; Saleh, George M; Park, Yoon Soo; la Cour, Morten; Konge, Lars

2017-04-01

To investigate the effect of virtual reality proficiency-based training on actual cataract surgery performance. The secondary purpose of the study was to define which surgeons benefit from virtual reality training. Multicenter masked clinical trial. Eighteen cataract surgeons with different levels of experience. Cataract surgical training on a virtual reality simulator (EyeSi) until a proficiency-based test was passed. Technical performance in the operating room (OR) assessed by 3 independent, masked raters using a previously validated task-specific assessment tool for cataract surgery (Objective Structured Assessment of Cataract Surgical Skill). Three surgeries before and 3 surgeries after the virtual reality training were video-recorded, anonymized, and presented to the raters in random order. Novices (non-independently operating surgeons) and surgeons having performed fewer than 75 independent cataract surgeries showed significant improvements in the OR-32% and 38%, respectively-after virtual reality training (P = 0.008 and P = 0.018). More experienced cataract surgeons did not benefit from simulator training. The reliability of the assessments was high with a generalizability coefficient of 0.92 and 0.86 before and after the virtual reality training, respectively. Clinically relevant cataract surgical skills can be improved by proficiency-based training on a virtual reality simulator. Novices as well as surgeons with an intermediate level of experience showed improvement in OR performance score. Copyright © 2017 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Association of vitamin C with the risk of age-related cataract: a meta-analysis.

PubMed

Wei, Lin; Liang, Ge; Cai, Chunmei; Lv, Jin

2016-05-01

Whether vitamin C is a protective factor for age-related cataract remains unclear. Thus, we conducted a meta-analysis to summarize the evidence from epidemiological studies of vitamin C and the risk of age-related cataract. Pertinent studies were identified by searching in PubMed and in Webscience. The random effect model was used to combine the results. Meta-regression and subgroups analyses were used to explore potential sources of between-study heterogeneity. Publication bias was estimated using Egger's regression asymmetry test. Finally, 15 articles with 20 studies for vitamin C intake and eight articles with 10 studies for serum ascorbate were included in this meta-analysis. The relative risk (RR) and 95% confidence interval of cataract for the highest versus the lowest category of vitamin C intake was 0.814 (0.707-0.938), and the associations were significant in America and Asia. Significant association of cataract risk with highest versus the lowest category of serum ascorbate was found in general [0.704 (0.564-0.879)]. Inverse associations were also found between serum ascorbate and nuclear cataract and posterior subcapsular cataract. Higher vitamin C intake and serum ascorbate might be inversely associated with risk of cataract. Vitamin C intake should be advocated for the primary prevention of cataract. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Simultaneous versus Sequential Bilateral Cataract Surgery for Infants with Congenital Cataracts: Visual Outcomes and Economic Costs

PubMed Central

Dave, Hreem; Phoenix, Vidya; Becker, Edmund R.; Lambert, Scott R.

2015-01-01

OBJECTIVES To compare the incidence of adverse events, visual outcomes and economic costs of sequential versus simultaneous bilateral cataract surgery for infants with congenital cataracts. METHODS We retrospectively reviewed the incidence of adverse events, visual outcomes and medical payments associated with simultaneous versus sequential bilateral cataract surgery for infants with congenital cataracts who underwent cataract surgery when 6 months of age or younger at our institution. RESULTS Records were available for 10 children who underwent sequential surgery at a mean age of 49 days for the first eye and 17 children who underwent simultaneous surgery at a mean age of 68 days (p=.25). We found a similar incidence of adverse events between the two treatment groups. Intraoperative or postoperative complications occurred in 14 eyes. The most common postoperative complication was glaucoma. No eyes developed endophthalmitis. The mean absolute interocular difference in logMAR visual acuities between the two treatment groups was 0.47±0.76 for the sequential group and 0.44±0.40 for the simultaneous group (p=.92). Hospital, drugs, supplies and professional payments were on average 21.9% lower per patient in the simultaneous group. CONCLUSIONS Simultaneous bilateral cataract surgery for infants with congenital cataracts was associated with a 21.9% reduction in medical payments and no discernible difference in the incidence of adverse events or visual outcome. PMID:20697007

Putative free radical-scavenging activity of an extract of Cineraria maritima in preventing selenite-induced cataractogenesis in Wistar rat pups

PubMed Central

Anitha, Thirugnanasambandhar Sivasubramanian; Muralidharan, Arumugam Ramachandran; Annadurai, Thangaraj; Jesudasan, Christdas Arul Nelson; Thomas, Philip Aloysius

2013-01-01

Purpose To investigate the possible free radical-scavenging activity of an extract of Cineraria maritima on selenite-induced cataractous lenses in Wistar rat pups. Methods In the present study, Wistar rat pups were divided into three experimental groups. On P10, Group I (control) rat pups received an intraperitoneal injection of 0.89% saline. Rats in groups II (selenite-challenged, untreated) and III (selenite-challenged, C. maritima treated) received a subcutaneous injection of sodium selenite (19 μmol/kg bodyweight); Group III rat pups also received an intraperitoneal injection of the extract of C. maritima (350 mg/kg bodyweight) once daily P9–14. Both eyes of each pup were examined from P16 until P30. Cytochemical localization of nitroblue tetrazolium salts and generation of superoxide, hydroxyl, and nitric oxide levels were measured. The expression of the inducible nitric oxide synthase gene was evaluated with reverse transcription-PCR. Immunoblot analysis was also performed to confirm the differential expression of the inducible nitric oxide synthase protein. Results Subcutaneous injection of sodium selenite led to severe oxidative damage in the lenticular tissues, shown by increased formation of formazan crystals, elevated generation of superoxide, hydroxyl, and nitric oxide radicals, and elevated inducible nitric oxide synthase gene and protein expression that possibly contributed to the opacification of the lens and thus cataract formation. When rat pups were treated with intraperitoneal administration of the extract of C. maritima, the generation of free radicals as well as the messenger ribonucleic acid and protein expression of inducible nitric oxide synthase were maintained at near normal levels. Conclusions The data generated by this study suggest that an ethanolic extract of C. maritima possibly prevents cataractogenesis in a rat model by minimizing free radical generation. PMID:24357923

Time-reversed ultrasonically encoded optical focusing through highly scattering ex vivo human cataractous lenses

NASA Astrophysics Data System (ADS)

Liu, Yan; Shen, Yuecheng; Ruan, Haowen; Brodie, Frank L.; Wong, Terence T. W.; Yang, Changhuei; Wang, Lihong V.

2018-01-01

Normal development of the visual system in infants relies on clear images being projected onto the retina, which can be disrupted by lens opacity caused by congenital cataract. This disruption, if uncorrected in early life, results in amblyopia (permanently decreased vision even after removal of the cataract). Doctors are able to prevent amblyopia by removing the cataract during the first several weeks of life, but this surgery risks a host of complications, which can be equally visually disabling. Here, we investigated the feasibility of focusing light noninvasively through highly scattering cataractous lenses to stimulate the retina, thereby preventing amblyopia. This approach would allow the cataractous lens removal surgery to be delayed and hence greatly reduce the risk of complications from early surgery. Employing a wavefront shaping technique named time-reversed ultrasonically encoded optical focusing in reflection mode, we focused 532-nm light through a highly scattering ex vivo adult human cataractous lens. This work demonstrates a potential clinical application of wavefront shaping techniques.

The global burden of cataract.

PubMed

Rao, Gullapalli N; Khanna, Rohit; Payal, Abhishek

2011-01-01

To review the previous year's literature related to prevalence of blindness in general, blindness due to cataract, cataract surgical coverage (CSC) and cataract surgical rates (CSRs). Cataracts are the major cause of blindness and visual impairment in developing countries and contributes to more than 90% of the total disability adjusted life years. This review shows that coverage continues to be a problem in many countries, especially for the female population, those residing in rural areas and those who are illiterate. Although CSR is an indicator of the availability and acceptability of services, for measuring the impact of the program, we should look at combining CSR with CSC. This strategy would also enable us achieve our goal of eliminating avoidable blindness due to cataracts by the year 2020. Cataracts still continue- to be a major cause of blindness globally and with the rapidly aging population, it is a challenge to tackle. We need to plan a comprehensive strategy addressing issues related to availability, affordability, accessibility and acceptability of eye-care services.

Rosmarinic Acid Restores Complete Transparency of Sonicated Human Cataract Ex Vivo and Delays Cataract Formation In Vivo.

PubMed

Chemerovski-Glikman, Marina; Mimouni, Michael; Dagan, Yarden; Haj, Esraa; Vainer, Igor; Allon, Raviv; Blumenthal, Eytan Z; Adler-Abramovich, Lihi; Segal, Daniel; Gazit, Ehud; Zayit-Soudry, Shiri

2018-06-19

Cataract, the leading cause of vision impairment worldwide, arises from abnormal aggregation of crystallin lens proteins. Presently, surgical removal is the only therapeutic approach. Recent findings have triggered renewed interest in development of non-surgical treatment alternatives. However, emerging treatments are yet to achieve full and consistent lens clearance. Here, the first ex vivo assay to screen for drug candidates that reduce human lenticular protein aggregation was developed. This assay allowed the identification of two leading compounds as facilitating the restoration of nearly-complete transparency of phacoemulsified cataractous preparation ex vivo. Mechanistic studies demonstrated that both compounds reduce cataract microparticle size and modify their amyloid-like features. In vivo studies confirmed that the lead compound, rosmarinic acid, delays cataract formation and reduces the severity of lens opacification in model rats. Thus, the ex vivo assay may provide an initial platform for broad screening of potential novel therapeutic agents towards pharmacological treatment of cataract.

Impact of Oncoming Headlight Glare With Cataracts: A Pilot Study

PubMed Central

Hwang, Alex D.; Tuccar-Burak, Merve; Goldstein, Robert; Peli, Eli

2018-01-01

Purpose: Oncoming headlight glare (HLG) reduces the visibility of objects on the road and may affect the safety of nighttime driving. With cataracts, the impact of oncoming HLG is expected to be more severe. We used our custom HLG simulator in a driving simulator to measure the impact of HLG on pedestrian detection by normal vision subjects with simulated mild cataracts and by patients with real cataracts. Methods: Five normal vision subjects drove nighttime scenarios under two HLG conditions (with and without HLG: HLGY and HLGN, respectively), and three vision conditions (with plano lens, simulated mild cataract, and optically blurred clip-on). Mild cataract was simulated by applying a 0.8 Bangerter diffusion foil to clip-on plano lenses. The visual acuity with the optically blurred lenses was individually chosen to match the visual acuity with the simulated cataract clip-ons under HLGN. Each nighttime driving scenario contains 24 pedestrian encounters, encompassing four pedestrian types; walking along the left side of the road, walking along the right side of the road, crossing the road from left to right, and crossing the road from right to left. Pedestrian detection performances of five patients with mild real cataracts were measured using the same setup. The cataract patients were tested only in HLGY and HLGN conditions. Participants’ visual acuity and contrast sensitivity were also measured in the simulator with and without stationary HLG. Results: For normal vision subjects, both the presence of oncoming HLG and wearing the simulated cataract clip-on reduced pedestrian detection performance. The subjects performed worst in events where the pedestrian crossed from the left, followed by events where the pedestrian crossed from the right. Significant interactions between HLG condition and other factors were also found: (1) the impact of oncoming HLG with the simulated cataract clip-on was larger than with the plano lens clip-on, (2) the impact of oncoming HLG was larger with the optically blurred clip-on than with the plano lens clip-on, but smaller than with the simulated cataract clip-on, and (3) the impact was larger for the pedestrians that crossed from the left than those that crossed from the right, and for the pedestrians walking along the left side of the road than walking along the right side of the road, suggesting that the pedestrian proximity to the glare source contributed to the performance reduction. Under HLGN, almost no pedestrians were missed with the plano lens or the simulated cataract clip-on (0 and 0.5%, respectively), but under HLGY, the rate of pedestrian misses increased to 0.5 and 6%, respectively. With the optically blurred clip-on, the percent of missed pedestrians under HLGN and HLGY did not change much (5% and 6%, respectively). Untimely response rate increased under HLGY with the plano lens and simulated cataract clip-ons, but the increase with the simulated cataract clip-on was significantly larger than with the plano lens clip-on. The contrast sensitivity with the simulated cataract clip-on was significantly degraded under HLGY. The visual acuity with the plano lens clip-on was significantly improved under HLGY, possibly due to pupil myosis. The impact of HLG measured for real cataract patients was similar to the impact on performance of normal vision subjects with simulated cataract clip-ons. Conclusion: Even with mild (simulated or real) cataracts, a substantial negative effect of oncoming HLG was measurable in the detection of crossing and walking-along pedestrians. The lowered pedestrian detection rates and longer response times with HLGY demonstrate a possible risk that oncoming HLG poses to patients driving with cataracts. PMID:29559933

Topical Anesthesia for Cataract Surgery: The Patients' Perspective

PubMed Central

Apil, Aytekin; Ekinci, Metin; Cagatay, Halil Huseyin; Keles, Sadullah; Ceylan, Erdinc; Cakici, Ozgur

2014-01-01

Purpose. To evaluate the analgesic efficacy of 0.5% propacaine hydrochloride as topical anesthesia during phacoemulsification surgery. Methods. Intraoperative pain intensity was assessed using a 5-category verbal rating scale during each of three surgical stages. Pain scores from each surgical stage and total pain scores were compared for the factors of patient age, gender, cataract laterality, and type. Results. In comparison of cataract type subgroups, the mean total pain scores and mean stage 2 pain scores in both white mature cataract (WMC) and corticonuclear plus posterior subcapsular cataract (CN + PSC) groups were significantly higher than in the PSC-only (PSC) group (P < 0.05). Conclusion. Phacoemulsification with topical anesthesia is not a completely painless procedure. Pain intensity varies with cataract type and stage of surgery. PMID:25050180

Early changes in morphology and intraocular pressure by size of clear corneal incision.

PubMed

Cheng, Bing; Liu, Yi; Liu, Yizhi; Xie, Bin Bin; Xi, Lei; Yang, Ye

2011-06-01

We compared changes in morphology and intraocular pressure (IOP) induced by clear 2.2-mm and 3.0-mm corneal incisions in a cohort of patients with cataracts. In 160 eyes (from 70 men and 90 women at the Ophthalmic Center of Sun Yat-sen University), optical coherence tomography and tonometry were performed at 1, 5, and 24 hours after cataract surgery. The main outcome measures were IOP, postoperative changes in Descemet membrane detachment (DMD), healing of the surgical incision, and inflammation of the anterior chamber. Five hours after surgery, patients with 2.2-mm and 3.0-mm incisions had lower IOPs (P < 0.017) as measured by noncontact tonometry, but the difference was significant only among patients with grade V cataracts (2.2 mm, 12.6 ± 1.2 mm Hg; 3.0 mm, 14.5 ± 0.9 mm Hg, P < 0.05). The incidence of endothelial gap at 24 hours after surgery was significantly higher in the 2.2-mm (50%) versus 3.0-mm (11.1%) group of patients with grade V cataracts (P < 0.05). The incidence of DMD at 5 hours was also significantly higher in the 2.2-mm group (75%) than in the 3.0-mm group (22.2%) only among patients with this grade (P < 0.05). Incision width made no difference among patients with grade I-IV lens nuclei; but among those with grade V, 3.0-mm incisions had significantly less endothelial gaping, less DMD, and higher mean IOPs. For these patients, smaller incisions may not be optimal, and eyes may be especially vulnerable within 5 hours of surgery.

A comparable study of clinical and optical outcomes after 1.8, 2.0 mm microcoaxial and 3.0 mm coaxial cataract surgery.

PubMed

Yu, Yi-Bo; Zhu, Ya-Nan; Wang, Wei; Zhang, Yi-Dong; Yu, Yin-Hui; Yao, Ke

2016-01-01

To evaluate the clinical and optical outcomes after clear corneal incision cataract surgery (CICS) with three different incision sizes (1.8, 2.0 and 3.0 mm). Eyes of 150 patients with age-related cataract scheduled for coaxial cataract surgery were randomized to three groups: 1.8, 2.0, or 3.0 mm CICS. Intraoperative data and postoperative outcomes including surgically induced astigmatism (SIA), the corneal incision thickness, wavefront aberrations and modulation transfer function (MTF) of cornea were obtained. There were no significant differences among the three groups in demographic characteristics and intraoperative outcome. The 1.8 and 2.0 mm microincisions showed more satisfactory clinical outcomes than the 3.0 mm incision. The 1.8 mm incision showed significantly less SIA than the 2.0 mm incision until postoperative 1mo (P<0.05), but the difference was only 0.14-0.18 D. Combined with less increased incision thickness only at postoperative 1d (P=0.013), the 1.8 mm incision presented better uncorrected distance visual acuity (UCDVA) than the 2.0 mm incision only at 1d postoperatively (P=0.008). For higher-order aberrations and other Zernike coefficients, there were no significant differences between the 1.8 mm group and 2.0 mm group (P>0.05). Converting from 3.0 mm CICS to 1.8 or 2.0 mm CICS result in better clinical and optical outcomes. However, when incision is 1.8 mm, the benefits from further reduction in size compared with 2.0 mm are limited. The necessity to reduce the incision size is to be deliberated.

Therapeutic uses of drug-carrier systems for imidazole-containing dipeptide compounds that act as pharmacological chaperones and have significant impact on the treatment of chronic diseases associated with increased oxidative stress and the formation of advanced glycation end products.

PubMed

Babizhayev, Mark A; Yegorov, Yegor E

2010-01-01

The purpose of this study was to determine how the naturally occurring molecules N-acetylcarnosine, L-carnosine, and carcinine, which are chemical or pharmacological chaperones, affect the cells and biomolecules of patients with skin diseases, cosmetic skin lesions, or underlying clinically significant visual impairment such as age-related cataracts, age-related retinal degeneration, and ocular complications of diabetes. We evaluated and characterized the effects of cited pharmacological chaperones on enzyme activity, protein structure in tissues, and other biomarkers of diseases in skin cells and tissues or in ocular tissues (human cataractous and normal lenses) derived from ophthalmic patients or age-matched donors. The samples were used to test imidazole-containing peptidomimetic chemical/pharmacological chaperones in relation to oxidative stress induced by reaction with lipid peroxides or advanced non-enzymatic glycation processes. Chaperone function is characterized by interaction with other proteins, mediating their folding, transport, and interaction with other molecules, lipid peroxidation products, and membranes. Although these therapies remain on hold pending further investigation, we present growing evidence demonstrating the ability of N-acetylcarnosine (lubricant eye drops) or carcinine pharmacological chaperone therapy to act as novel treatments for age-related cataracts, age-related macular degeneration, and ocular complications of diabetes. Finally, we examine strategies for identifying potential chaperone compounds and for experimentally demonstrating chaperone and transglycating (de-glycation) types of activity in in vitro and in vivo models of human age-related eye diseases, such as cataracts, and advanced glycation tissue protein-engineered systems.

Entropic Imaging of Cataract Lens: An In Vitro Study

PubMed Central

Shung, K. Kirk; Tsui, Po-Hsiang; Fang, Jui; Ma, Hsiang-Yang; Wu, Shuicai; Lin, Chung-Chih

2014-01-01

Phacoemulsification is a common surgical method for treating advanced cataracts. Determining the optimal phacoemulsification energy depends on the hardness of the lens involved. Previous studies have shown that it is possible to evaluate lens hardness via ultrasound parametric imaging based on statistical models that require data to follow a specific distribution. To make the method more system-adaptive, nonmodel-based imaging approach may be necessary in the visualization of lens hardness. This study investigated the feasibility of applying an information theory derived parameter – Shannon entropy from ultrasound backscatter to quantify lens hardness. To determine the physical significance of entropy, we performed computer simulations to investigate the relationship between the signal-to-noise ratio (SNR) based on the Rayleigh distribution and Shannon entropy. Young's modulus was measured in porcine lenses, in which cataracts had been artificially induced by the immersion in formalin solution in vitro. A 35-MHz ultrasound transducer was used to scan the cataract lenses for entropy imaging. The results showed that the entropy is 4.8 when the backscatter data form a Rayleigh distribution corresponding to an SNR of 1.91. The Young's modulus of the lens increased from approximately 8 to 100 kPa when we increased the immersion time from 40 to 160 min (correlation coefficient r = 0.99). Furthermore, the results indicated that entropy imaging seemed to facilitate visualizing different degrees of lens hardening. The mean entropy value increased from 2.7 to 4.0 as the Young's modulus increased from 8 to 100 kPa (r = 0.85), suggesting that entropy imaging may have greater potential than that of conventional statistical parametric imaging in determining the optimal energy to apply during phacoemulsification. PMID:24760103

Risk of cataract in persons with cytomegalovirus retinitis and the acquired immune deficiency syndrome.

PubMed

Kempen, John H; Sugar, Elizabeth A; Lyon, Alice T; Lewis, Richard Alan; Jabs, Douglas A; Heinemann, Murk-Hein; Dunn, James P

2012-11-01

To evaluate cataract risk in eyes of patients with AIDS and cytomegalovirus (CMV) retinitis and to identify risk factors. Prospective cohort study. Patients with AIDS and CMV retinitis. Patients 13 years of age and older were enrolled between 1998 and 2008. Demographic and clinical characteristics, slit-lamp biomicroscopy findings, and dilated ophthalmoscopy results were documented at quarterly visits. Cataract status was determined at the initial visit (prevalence) and at follow-up visits (incidence). For cataract, a high grade of lens opacity by biomicroscopy to which best-corrected visual acuity worse than 20/40 was attributed. Eyes that had undergone cataract surgery before enrollment or between visits also were counted as having cataract. Seven hundred twenty-nine eyes of 489 patients diagnosed with CMV retinitis were evaluated. Higher prevalence was observed for patients with bilateral versus unilateral CMV retinitis (adjusted odds ratio [aOR], 2.74; 95% confidence interval [CI], 1.76-4.26) and, among unilateral CMV retinitis cases, for eyes with retinitis versus without retinitis (15% vs. 1.4%; P<0.0001). The age-adjusted prevalence of cataract among CMV retinitis cases was higher than that in a population-based sample (P<0.0001). Cataract prevalence increased with age (aOR, 11.77; 95% CI, 2.28-60.65 for age ≥ 60 years vs. younger than 40 years) and longer duration of retinitis (aOR, 1.36; 95% CI, 1.20-1.54 per year). Among eyes with CMV retinitis initially free of cataract, the cataract incidence was 8.1%/eye-year (95% CI, 6.7%-10.0%). Prior retinal detachment was associated with higher cataract risk (if repaired with silicone oil: adjusted hazard ratio [aHR], 10.37; 95% CI, 6.51-16.52; otherwise: aHR, 2.90; 95% CI, 1.73-4.87). Large CMV retinitis lesions also were associated with higher risk of cataract (for involvement of 25-49% retinal area: aHR, 2.30; 95% CI, 1.51-3.50; for ≥ 50% involvement: aHR, 3.63; 95% CI, 2.18-6.04), each with respect to ≤ 24% involvement, as were anterior segment inflammation (aHR, 2.27; 95% CI, 1.59-3.25) and contralateral cataract (aHR, 2.52; 95% CI, 1.74-3.66). Cytomegalovirus retinitis is associated with a high absolute and relative risk of cataract. Among several risk factors, large retinal lesion size and use of silicone oil in retinal detachment repair are potentially modifiable, albeit not in all cases. Cataract is likely to be an increasingly important cause of visual morbidity in this population. Copyright © 2012 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Risk of Cataract in Persons with Cytomegalovirus Retinitis and the Acquired Immune Deficiency Syndrome

PubMed Central

Kempen, John H.; Sugar, Elizabeth A.; Lyon, Alice T.; Lewis, Richard Alan; Jabs, Douglas A.; Heinemann, Murk-Hein; Dunn, James P.

2012-01-01

Objective To evaluate cataract risk in eyes of patients with AIDS and cytomegalovirus (CMV) retinitis and to identify risk factors. Design Prospective cohort study. Participants Patients with AIDS and CMV retinitis. Methods Patients 13 years of age and older were enrolled between 1998 and 2008. Demographic and clinical characteristics, slit-lamp biomicroscopy findings, and dilated ophthalmoscopy results were documented at quarterly visits. Cataract status was determined at the initial visit (prevalence) and at follow-up visits (incidence). Main Outcome Measures For cataract, a high grade of lens opacity by biomicroscopy to which best-corrected visual acuity worse than 20/40 was attributed. Eyes that had undergone cataract surgery before enrollment or between visits also were counted as having cataract. Results Seven hundred twenty-nine eyes of 489 patients diagnosed with CMV retinitis were evaluated. Higher prevalence was observed for patients with bilateral versus unilateral CMV retinitis (adjusted odds ratio [aOR], 2.74; 95% confidence interval [CI], 1.76–4.26) and, among unilateral CMV retinitis cases, for eyes with retinitis versus without retinitis (15% vs. 1.4%; P<0.0001). The age-adjusted prevalence of cataract among CMV retinitis cases was higher than that in a population-based sample (P<0.0001). Cataract prevalence increased with age (aOR, 11.77; 95% CI, 2.28–60.65 for age ≥60 years vs. younger than 40 years) and longer duration of retinitis (aOR, 1.36; 95% CI, 1.20–1.54 per year). Among eyes with CMV retinitis initially free of cataract, the cataract incidence was 8.1%/eye-year (95% CI, 6.7%–10.0%). Prior retinal detachment was associated with higher cataract risk (if repaired with silicone oil: adjusted hazard ratio [aHR], 10.37; 95% CI, 6.51–16.52; otherwise: aHR, 2.90; 95% CI, 1.73–4.87). Large CMV retinitis lesions also were associated with higher risk of cataract (for involvement of 25–49% retinal area: aHR, 2.30; 95% CI, 1.51–3.50; for ≥50% involvement: aHR, 3.63; 95% CI, 2.18–6.04), each with respect to ≤24% involvement, as were anterior segment inflammation (aHR, 2.27; 95% CI, 1.59–3.25) and contralateral cataract (aHR, 2.52; 95% CI, 1.74–3.66). Conclusions Cytomegalovirus retinitis is associated with a high absolute and relative risk of cataract. Among several risk factors, large retinal lesion size and use of silicone oil in retinal detachment repair are potentially modifiable, albeit not in all cases. Cataract is likely to be an increasingly important cause of visual morbidity in this population. PMID:22853972

Tissue Culture Modelling of Microwave Induced Cataracts of the Eye Lens.

DTIC Science & Technology

1979-08-01

CONTROLLING OFFICE NAME AND ADDRESS RDR~d5- US Army Medical Research and Development Commiam jAug : Fort Detrick, Frederick, MD 21701. 13. NUMUEROFAES15 1...U.S.A. Table of Contents 1. Introduction ......................................................... 6 2. Materials and Methods...and abence of Vitamin E.....................................................13 °A 6 Introduction : IIt has been known for many years that cortical

Accuracy, Repeatability and Instrument Myopia Induced by a Clinical Aberrometer - The Complete Ophthalmic Analysis System (COAS)

DTIC Science & Technology

2006-06-01

measurement. The Lancet, 1, 307-3 10. Boxer Wachler, B.S. (2003). Effect of pupil size on visual function under monocular and binocular conditions in LASIK ...and non- LASIK patients. J Cataract Refract Surg, 29 (2), 275- 278. Boxer Wachler, B.S., Huynh, V.N., El-Shiaty, A.F., & Goldberg, D. (2002

UV-B-induced damage to the lens in vitro: prevention by caffeine.

PubMed

Varma, Shambhu D; Hegde, Kavita R; Kovtun, Svitlana

2008-10-01

Ultraviolet (UV) irradiation is one of the significant risk factors in the genesis of cataracts. Pathogenetically, the process can be triggered by the intraocular generation of various reactive species of oxygen that are well known to be initiated by the penetration of light, especially of the UV frequencies. The contribution of UV exposure in the etiology of this disease is likely to increase further due to ozone depletion in the upper atmosphere. The present studies were undertaken to examine if the UV effects can be attenuated with the xanthine-based alkaloids primarily present in tea and coffee. We have examined this possibility by in vitro lens culture studies with caffeine. As expected, mice lenses incubated in Tyrode solution exposed to UV at 302 nm are physiologically damaged, as evidenced by the inhibition of the active transport of (86)Rb(+), an ion acting as a surrogate of the K(+). There was a simultaneous decrease in the levels of adenosine triphosphate and glutathione. The addition of caffeine to the medium prevented such deleterious effects. That caffeine and perhaps other xanthinoids have a protective effect against cataract formation induced by UV has hence been demonstrated for the first time.

Extensive bilateral corneal edema 6 weeks after cataract surgery: Keratopathy due to Asclepias physocarpa: a case report.

PubMed

Matsuura, Kazuki; Hatta, Shiro; Terasaka, Yuki; Inoue, Yoshitsugu

2017-01-18

Surgeons may be unaware of the ability of plant toxins to cause corneal damage. Therefore, corneal damage following intraocular surgery due to plant toxins may be misdiagnosed as postoperative infection. A 74-year-old man presented with hyperemia and reduced visual acuity in both eyes 6 weeks after uneventful cataract surgery. We observed extensive hyperemia and corneal stromal edema with Descemet's folds in both eyes. After obtaining a detailed patient history, we diagnosed plant toxin-induced corneal edema due to Asclepias physocarpa, which can induce corneal edema by inhibiting the Na + /K + ATPase activity of the corneal endothelium. Antimicrobial and steroid eye drops and an oral steroid were prescribed accordingly. Symptons began to improve on day 3 and had almost completely resolved by day 6. At 1 month, the patient had fully recovered without any sequelae. The correct diagnosis was possible in the present case as symptoms were bilateral and the patient was able to report his potential exposure to plant toxins. However, if the symptoms had been unilateral and the patient had been unaware of these toxins, he may have undergone unnecessary surgical interventions to treat non-existent postoperative endophthalmitis.

Cataract, visual impairment and long-term mortality in a rural cohort in India: the Andhra Pradesh Eye Disease Study.

PubMed

Khanna, Rohit C; Murthy, Gudlavalleti V S; Giridhar, Pyda; Krishnaiah, Sannapaneni; Pant, Hira B; Palamaner Subash Shantha, Ghanshyam; Chakrabarti, Subhabrata; Gilbert, Clare; Rao, Gullapalli N

2013-01-01

A large-scale prevalence survey of blindness and visual impairment (The Andhra Pradesh Eye Diseases Study [APEDS1]) was conducted between 1996-2000 on 10,293 individuals of all ages in three rural and one urban clusters in Andhra Pradesh, Southern India. More than a decade later (June 2009-March 2010), APEDS1 participants in rural clusters were traced (termed APEDS2) to determine ocular risk factors for mortality in this longitudinal cohort. Mortality hazard ratio (HR) analysis was performed for those aged >30 years at APEDS1, using Cox proportional hazard regression models to identify associations between ocular exposures and risk of mortality. Blindness and visual impairment (VI) were defined using Indian definitions. 799/4,188 (19.1%) participants had died and 308 (7.3%) had migrated. Mortality was higher in males than females (p<0.001). In multivariable analysis, after adjusting for age, gender, diabetes, hypertension, body mass index, smoking and education status the mortality HR was 1.9 (95% CI: 1.5-2.5) for blindness; 1.4 (95% CI: 1.2-1.7) for VI; 1.8 (95% CI: 1.4-2.3) for pure nuclear cataract, 1.5 (95% CI: 1.1-2.1) for pure cortical cataract; 1.96 (95% CI: 1.6-2.4) for mixed cataract, 2.0 (95% CI: 1.4-2.9) for history of cataract surgery, and 1.58 (95% CI: 1.3-1.9) for any cataract. When all these factors were included in the model, the HRs were attenuated, being 1.5 (95% CI: 1.1-2.0) for blindness and 1.2 (95% CI: 0.9-1.5) for VI. For lens type, the HRs were as follows: pure nuclear cataract, 1.6 (95% CI: 1.3-2.1); pure cortical cataract, 1.5 (95% CI: 1.1-2.1); mixed cataract, 1.8 (95% CI: 1.4-2.2), and history of previous cataract surgery, 1.8 (95% CI: 1.3-2.6). All types of cataract, history of cataract surgery and VI had an increased risk of mortality that further suggests that these could be potential markers of ageing.

Long-term physical activity and risk of age-related cataract: a population-based prospective study of male and female cohorts.

PubMed

Zheng Selin, Jinjin; Orsini, Nicola; Ejdervik Lindblad, Birgitta; Wolk, Alicja

2015-02-01

To examine the association of total and specific types of physical activity, including walking or bicycling, exercising, work or occupational activity, home or housework, and leisure time inactivity with the risk of age-related cataract in women and men. Population-based prospective cohort study. A total of 52 660 participants (23 853 women and 28 807 men) 45 to 83 years of age from the Swedish Mammography Cohort and the Cohort of Swedish Men. Physical activity was assessed using a self-administered questionnaire at baseline. Cataract diagnosis and extraction were identified through linkage to registers. Incident age-related cataract diagnosis and cataract extraction. During a mean 12.1 years of follow-up (between January 1, 1998, and December 31, 2011; 634 631 person-years), 11 580 incident age-related cataract cases were identified. After adjusting for potential confounders, the highest quartile of total physical activity was statistically significantly associated with 13% decreased risk of cataract compared with the lowest (hazard ratio [HR], 0.87; 95% confidence interval [CI], 0.82-0.92). Walking or bicycling (>60 minutes/day vs. hardly ever; HR, 0.88; 95% CI, 0.82-0.95) and work or occupational activity (heavy manual labor vs. mostly sitting; HR, 0.84; 95% CI, 0.78-0.91) also were associated with decreased risk of cataract. Exercise training and home or housework were not associated with cataract risk. Leisure time inactivity was associated with increased risk of cataract (>6 vs. <1 hours/day; HR, 1.27; 95% CI, 1.07-1.50). The HR for high long-term total physical activity compared with low levels both at 30 years of age and at baseline was 0.76 (95% CI, 0.69-0.85). Our findings indicate that high total physical activity, especially in the long term, and such specific types of physical activity as walking or bicycling and work or occupational activity, may be associated with decreased risk of age-related cataract. Conversely, high inactivity levels may be associated with increased risk of cataract. Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Sunshine is good medicine. The health benefits of ultraviolet-B induced vitamin D production.

PubMed

Grant, W B; Strange, R C; Garland, C F

2003-04-01

Most public health statements regarding exposure to solar ultraviolet radiation (UVR) recommend avoiding it, especially at midday, and using sunscreen. Excess UVR is a primary risk factor for skin cancers, premature photoageing and the development of cataracts. In addition, some people are especially sensitive to UVR, sometimes due to concomitant illness or drug therapy. However, if applied uncritically, these guidelines may actually cause more harm than good. Humans derive most of their serum 25-hydroxycholecalciferol (25(OH)D3) from solar UVB radiation (280-315 nm). Serum 25(OH)D3 metabolite levels are often inadequate for optimal health in many populations, especially those with darker skin pigmentation, those living at high latitudes, those living largely indoors and in urban areas, and during winter in all but the sunniest climates. In the absence of adequate solar UVB exposure or artificial UVB, vitamin D can be obtained from dietary sources or supplements. There is compelling evidence that low vitamin D levels lead to increased risk of developing rickets, osteoporosis and osteomaloma, 16 cancers (including cancers of breast, ovary, prostate and non-Hodgkin's lymphoma), and other chronic diseases such as psoriasis, diabetes mellitus, hypertension, heart disease, myopathy, multiple sclerosis, schizophrenia, hyperparathyroidism and susceptibility to tuberculosis. The health benefits of UVB seem to outweigh the adverse effects. The risks can be minimized by avoiding sunburn, excess UVR exposure and by attention to dietary factors, such as antioxidants and limiting energy and fat consumption. It is anticipated that increasing attention will be paid to the benefits of UVB radiation and vitamin D and that health guidelines will be revised in the near future.

Global prevalence and economic and humanistic burden of astigmatism in cataract patients: a systematic literature review.

PubMed

Anderson, David F; Dhariwal, Mukesh; Bouchet, Christine; Keith, Michael S

2018-01-01

To systematically review the published evidence on the prevalence and economic and humanistic burden of astigmatism in cataract patients. For this systematic literature review, the Medline, PubMed, Embase, and Cochrane databases were searched from 1996 to September 2015 for available scientific literature that met the inclusion criteria. Studies published in the English language reporting prevalence and humanistic and economic burden in patients diagnosed with cataract and astigmatism were included. Of 3,649 papers reviewed, 31 studies from 32 publications met the inclusion criteria of this review. Preexisting astigmatism ≥1 D was present in up to 47% of cataract eyes. The cost burden of residual uncorrected astigmatism after cataract surgery was driven by the cost of spectacles, which was estimated to range from $2,151 to $3,440 in the US and $1,786 to $4,629 in Europe over a lifetime. In cataract patients, both preexisting and postoperative residual astigmatism were associated with poor vision-related patient satisfaction and quality of life, as well as higher spectacle burden. Astigmatism correction during cataract surgery appears to improve visual outcomes and results in overall lifetime cost savings compared to astigmatism correction with postoperative vision correction. There is a high prevalence of preexisting astigmatism in cataract patients. Although published data are limited, both preoperative astigmatism and postoperative residual astigmatism affect visual function and vision-related quality of life, resulting in increased humanistic burden. Suboptimal correction of astigmatism during cataract surgery drives the continuous need for vision correction with spectacles in the postoperative period. Patients must bear the out-of-pocket expenses, since payers often do not reimburse the cost of spectacles. Greater access to astigmatism correction during cataract surgery could improve visual outcomes and quality of life in patients. More research is required to gain a better understanding of the disease burden of astigmatism in cataract patients.

Global prevalence and economic and humanistic burden of astigmatism in cataract patients: a systematic literature review

PubMed Central

Anderson, David F; Dhariwal, Mukesh; Bouchet, Christine; Keith, Michael S

2018-01-01

Purpose To systematically review the published evidence on the prevalence and economic and humanistic burden of astigmatism in cataract patients. Materials and methods For this systematic literature review, the Medline, PubMed, Embase, and Cochrane databases were searched from 1996 to September 2015 for available scientific literature that met the inclusion criteria. Studies published in the English language reporting prevalence and humanistic and economic burden in patients diagnosed with cataract and astigmatism were included. Results Of 3,649 papers reviewed, 31 studies from 32 publications met the inclusion criteria of this review. Preexisting astigmatism ≥1 D was present in up to 47% of cataract eyes. The cost burden of residual uncorrected astigmatism after cataract surgery was driven by the cost of spectacles, which was estimated to range from $2,151 to $3,440 in the US and $1,786 to $4,629 in Europe over a lifetime. In cataract patients, both preexisting and postoperative residual astigmatism were associated with poor vision-related patient satisfaction and quality of life, as well as higher spectacle burden. Astigmatism correction during cataract surgery appears to improve visual outcomes and results in overall lifetime cost savings compared to astigmatism correction with postoperative vision correction. Conclusion There is a high prevalence of preexisting astigmatism in cataract patients. Although published data are limited, both preoperative astigmatism and postoperative residual astigmatism affect visual function and vision-related quality of life, resulting in increased humanistic burden. Suboptimal correction of astigmatism during cataract surgery drives the continuous need for vision correction with spectacles in the postoperative period. Patients must bear the out-of-pocket expenses, since payers often do not reimburse the cost of spectacles. Greater access to astigmatism correction during cataract surgery could improve visual outcomes and quality of life in patients. More research is required to gain a better understanding of the disease burden of astigmatism in cataract patients. PMID:29563768

Long-Term Visual Outcomes of Secondary Intraocular Lens Implantation in Children with Congenital Cataracts

PubMed Central

Jiang, Yongxiang; Lu, Yi

2015-01-01

Aim The aim of this study was to evaluate the long-term visual outcomes and factors affecting visual results in children undergoing secondary intraocular lens (IOL) implantation following primary congenital cataract extraction. Methods Children with congenital cataracts who underwent secondary IOL implantation for aphakia at the Eye and ENT Hospital of Fudan University between January 1, 2001, and December 31, 2007, were retrospectively reviewed. One eye was randomly selected in children with bilateral cataracts. Laterality, type of cataract (total or partial opacity), sex, age at primary and secondary surgeries, visual axis opacity (VAO), compliance with amblyopia therapy, postoperative ocular complications, refractive error, ocular alignment, and best corrected visual acuity (BCVA) at last follow-up were recorded; potential factors that might have affected the visual results were evaluated. Results Seventy-six bilateral and 34 unilateral congenital cataract cases were analyzed; the mean ages of the children were 12.70±5.06 and 12.50±2.71 years at final follow-up, the mean follow-up periods from IOL implantation were 94.93±24.22 and 109.09±18.89 months, and the mean BCVA (Log MAR) values were 0.51±0.37 and 1.05±0.46, respectively. Final BCVA after secondary IOL implantation was significantly associated with laterality, type of cataract, age at primary cataract extraction, compliance with amblyopia therapy, and refractive correction after surgery. No significant associations were found between BCVA and sex, age at secondary IOL implantation, VAO, or other ocular complications. The most common ocular complications were VAO and elevated intraocular pressure after surgery. There were no other complications, with the exception of one eye with IOL dislocation. Conclusions The results indicate that the important determinants of long-term visual outcomes in children with congenital cataracts undergoing secondary IOL implantation are laterality, cataract type, age at initial cataract extraction, compliance with amblyopia therapy, and refractive error. PMID:26230501

Use of Cooking Fuels and Cataract in a Population-Based Study: The India Eye Disease Study

PubMed Central

Ravilla, Thulasiraj D.; Gupta, Sanjeev; Ravindran, Ravilla D.; Vashist, Praveen; Krishnan, Tiruvengada; Maraini, Giovanni; Chakravarthy, Usha; Fletcher, Astrid E.

2016-01-01

Background: Biomass cooking fuels are commonly used in Indian households, especially by the poorest socioeconomic groups. Cataract is highly prevalent in India and the major cause of vision loss. The evidence on biomass fuels and cataract is limited. Objectives: To examine the association of biomass cooking fuels with cataract and type of cataract. Methods: We conducted a population-based study in north and south India using randomly sampled clusters to identify people ≥ 60 years old. Participants were interviewed and asked about cooking fuel use, socioeconomic and lifestyle factors and attended hospital for digital lens imaging (graded using the Lens Opacity Classification System III), anthropometry, and blood collection. Years of use of biomass fuels were estimated and transformed to a standardized normal distribution. Results: Of the 7,518 people sampled, 94% were interviewed and 83% of these attended the hospital. Sex modified the association between years of biomass fuel use and cataract; the adjusted odds ratio (OR) for a 1-SD increase in years of biomass fuel use and nuclear cataract was 1.04 (95% CI: 0.88, 1.23) for men and 1.28 (95% CI: 1.10, 1.48) for women, p interaction = 0.07. Kerosene use was low (10%). Among women, kerosene use was associated with nuclear (OR = 1.76, 95% CI: 1.04, 2.97) and posterior subcapsular cataract (OR = 1.71, 95% CI: 1.10, 2.64). There was no association among men. Conclusions: Our results provide robust evidence for the association of biomass fuels with cataract for women but not for men. Our finding for kerosene and cataract among women is novel and requires confirmation in other studies. Citation: Ravilla TD, Gupta S, Ravindran RD, Vashist P, Krishnan T, Maraini G, Chakravarthy U, Fletcher AE. 2016. Use of cooking fuels and cataract in a population-based study: the India Eye Disease Study. Environ Health Perspect 124:1857–1862; http://dx.doi.org/10.1289/EHP193 PMID:27227523

Use of Cooking Fuels and Cataract in a Population-Based Study: The India Eye Disease Study.

PubMed

Ravilla, Thulasiraj D; Gupta, Sanjeev; Ravindran, Ravilla D; Vashist, Praveen; Krishnan, Tiruvengada; Maraini, Giovanni; Chakravarthy, Usha; Fletcher, Astrid E

2016-12-01

Biomass cooking fuels are commonly used in Indian households, especially by the poorest socioeconomic groups. Cataract is highly prevalent in India and the major cause of vision loss. The evidence on biomass fuels and cataract is limited. To examine the association of biomass cooking fuels with cataract and type of cataract. We conducted a population-based study in north and south India using randomly sampled clusters to identify people ≥ 60 years old. Participants were interviewed and asked about cooking fuel use, socioeconomic and lifestyle factors and attended hospital for digital lens imaging (graded using the Lens Opacity Classification System III), anthropometry, and blood collection. Years of use of biomass fuels were estimated and transformed to a standardized normal distribution. Of the 7,518 people sampled, 94% were interviewed and 83% of these attended the hospital. Sex modified the association between years of biomass fuel use and cataract; the adjusted odds ratio (OR) for a 1-SD increase in years of biomass fuel use and nuclear cataract was 1.04 (95% CI: 0.88, 1.23) for men and 1.28 (95% CI: 1.10, 1.48) for women, p interaction = 0.07. Kerosene use was low (10%). Among women, kerosene use was associated with nuclear (OR = 1.76, 95% CI: 1.04, 2.97) and posterior subcapsular cataract (OR = 1.71, 95% CI: 1.10, 2.64). There was no association among men. Our results provide robust evidence for the association of biomass fuels with cataract for women but not for men. Our finding for kerosene and cataract among women is novel and requires confirmation in other studies. Citation: Ravilla TD, Gupta S, Ravindran RD, Vashist P, Krishnan T, Maraini G, Chakravarthy U, Fletcher AE. 2016. Use of cooking fuels and cataract in a population-based study: the India Eye Disease Study. Environ Health Perspect 124:1857-1862; http://dx.doi.org/10.1289/EHP193.

Zinc Supplementation Ameliorates Diabetic Cataract Through Modulation of Crystallin Proteins and Polyol Pathway in Experimental Rats.

PubMed

Barman, Susmita; Srinivasan, Krishnapura

2018-05-13

Non-enzymatic glycation of lens proteins and elevated polyol pathway in the eye lens have been the characteristic features of a diabetic condition. We have previously reported the benefits of zinc supplementation in reducing hyperglycemia and associated metabolic abnormalities and oxidative stress in diabetic rats. The current study explored whether zinc supplementation protects against cataractogenesis through modulation of glycation of lens proteins, elevated polyol pathway, oxidative stress, and proportion of different heat shock proteins in the eye lens of diabetic rats. Streptozotocin-induced diabetic rats were fed with a zinc-enriched diet (5 and 10 times of normal) for 6 weeks. Supplemental zinc alleviated the progression and maturation of diabetes-induced cataract. Zinc was also effective in preventing the reduced content of total and imbalanced proportion of soluble proteins in the lens. Supplemental zinc also alleviated cross-linked glycation and concomitant expression of the receptor of glycated products and oxidative stress indicators in the eye lens. Zinc supplementation further induced the concentration of heat shock protein in the eye lens of diabetic rats, specifically α-crystallin. Zinc supplementation counteracted the elevated activity and expression of polyol pathway enzymes and molecules in the lens. The results of this animal study endorsed the advantage of zinc supplementation in exerting the antiglycating influence and downregulating polyol pathway enzymes to defer cataractogenesis in diabetic rats.

Recognizing Cataracts

MedlinePlus

... age-related cataract. They recommend eating plenty of green leafy vegetables, fruits, nuts and other healthy foods. Also, don’t smoke, because smoking may speed cataract development. To screen for early signs of eye disease, Bishop recommends ...

Effect of cataract surgery on retinal nerve fiber layer thickness parameters using scanning laser polarimetry (GDxVCC)

PubMed Central

Dada, Tanuj; Behera, Geeta; Agarwal, Anand; Kumar, Sanjeev; Sihota, Ramanjit; Panda, Anita

2010-01-01

Purpose: To study the effect of cataract extraction on the retinal nerve fiber layer (RNFL) thickness, and assessment by scanning laser polarimetry (SLP), with variable corneal compensation (GDx VCC), at the glaucoma service of a tertiary care center in North India. Materials and Methods: Thirty-two eyes of 32 subjects were enrolled in the study. The subjects underwent RNFL analysis by SLP (GDx VCC) before undergoing phacoemulsification cataract extraction with intraocular lens (IOL) implantation (Acrysof SA 60 AT) four weeks following cataract surgery. The RNFL thickness parameters evaluated both before and after surgery included temporal, superior, nasal, inferior, temporal (TSNIT) average, superior average, inferior average, and nerve fiber index (NFI). Results: The mean age of subjects was 57.6 ± 11.7 years (18 males, 14 females). Mean TSNIT average thickness (μm) pre- and post-cataract surgery was 49.2 ± 14.1 and 56.5 ± 7.6 (P = 0.001). There was a statistically significant increase in RNFL thickness parameters (TSNIT average, superior average, and inferior average) and decrease in NFI post-cataract surgery as compared to the baseline values. Mean NFI pre- and post-cataract surgery was 41.3 ± 15.3 and 21.6 ± 11.8 (P = 0.001). Conclusions: Measurement of RNFL thickness parameters by scanning laser polarimetry is significantly altered following cataract surgery. Post the cataract surgery, a new baseline needs to be established for assessing the longitudinal follow-up of a glaucoma patient. The presence of cataract may lead to an underestimation of the RNFL thickness, and this should be taken into account when analyzing progression in a glaucoma patient. PMID:20689193

[Rehabilitation methods for children with complicated cataract].

PubMed

Ivanov, G; Cuşnir, V; Septichina, Natalia; Cuşnir, Vitalie

2010-01-01

The work deals with the results of surgical treatment of 155 patients, who had uveal cataract, by method of facoemulsification with artificial crystalline lens transplanting. The age of the sick varied from 3 to 15 as a result of a complex treatment, involving determination of ethnic factor in the development of uveal cataract, before- and after-operation conservative medical treatment, surgical treatment of abscuration ambliopia 78.1% children and the keenness of sight 0.4 and 68.7% got binocularious sight. The study lot of posttraumatic cataract affected children included 189 patients, from them 68 with stationary cataract, 87 with intumescent cataract and 34 with postoperatorial aphakia. Age from 2 to 15 years. 76.3% cases of evolution without postoperatorial complications, in 13.7% intraoperatorial were observed different complications. The work presents the results of surgical treatment 196 of children, who had innate cataract, by the method of facoasoriation with soft intra-eyepiece lens transplanting from 133 patients who had two-sided cataract, 63 had monolateral cataract. All children underwent laser simulation and videocomputer auto-training in post-operation period. As a result of the treatment, 66.8% patients got the amelioration of sight with 0.4, and 58% got binocular sight. The children's age varied between 6 months and 15 years. This article presents a review of the treatment results of 213 children with posttraumatic, congenital and complicated cataracts. The rehabilitation of the patients with the lens pathology includes a complex of measures of early diagnosis, surgery, optimal correction, medical treatment before and after surgery, the prophilaxis and treatment of complications. This approach permits to increase the visual acuity in 83.8% and to restore the binocular vision in 71.4% patients.

Coverage of hospital-based cataract surgery and barriers to the uptake of surgery among cataract blind persons in nigeria: the Nigeria National Blindness and Visual Impairment Survey.

PubMed

Abubakar, Tafida; Gudlavalleti, Murthy V S; Sivasubramaniam, Selvaraj; Gilbert, Clare E; Abdull, Mohammed M; Imam, Abdullahi U

2012-04-01

To determine cataract surgical coverage, and barriers to modern cataract surgery in Nigeria. Multistage stratified cluster random sampling was used to identify a nationally representative sample of 15,027 persons aged 40+ years. All underwent visual acuity testing, frequency doubling technology visual field testing, autorefraction, and measurement of best corrected vision if <6/12 in one or both eyes. An ophthalmologist examined the anterior segment and fundus through an undilated pupil for all participants. Participants were examined by a second ophthalmologist using a slit lamp and dilated fundus examination using a 90 diopter condensing lens if vision was <6/12 in one or both eyes, there were optic disc changes suggestive of glaucoma, and 1 in 7 participants regardless of findings. All those who had undergone cataract surgery were asked where and when this had taken place. Individuals who were severely visually impaired or blind from unoperated cataract were asked to explain why they had not undergone surgery. A total of 13,591 participants were examined (response rate 89.9%). Prevalence of cataract surgery was 1.6% (95% confidence interval 1.4-1.8), significantly higher among those aged ≥70 years. Cataract surgical coverage (persons) in Nigeria was 38.3%. Coverage was 1.7 times higher among males than females. Coverage was only 9.1% among women in the South-South geopolitical zone. Over one third of those who were cataract blind said they could not afford surgery (36%). Cataract surgical coverage in Nigeria was among the lowest in the world. Urgent initiatives are necessary to improve surgical output and access to surgery.

Revalidation and electronic cataract surgery audit: a Scottish survey on current practice and opinion.

PubMed

Megaw, R; Rane-Malcolm, T; Brannan, S; Smith, R; Sanders, R

2011-11-01

To determine current knowledge and opinion on revalidation, and methods of cataract surgery audit in Scotland and to outline the current and future possibilities for electronic cataract surgery audit. In 2010 we conducted a prospective, cross-sectional, Scottish-wide survey on revalidation knowledge and opinion, and cataract audit practice among all senior NHS ophthalmologists. Results were anonymised and recorded manually for analysis. In all, 61% of the ophthalmologists surveyed took part. Only 33% felt ready to take part in revalidation, whereas 76% felt they did not have adequate information about the process. Also, 71% did not feel revalidation would improve patient care, but 85% agreed that cataract surgery audit is essential for ophthalmic practice. In addition, 91% audit their cataract outcomes; 52% do so continuously. Further, 63% audit their subspecialist surgical results. Only 25% audit their cataract surgery practice electronically, and only 12% collect clinical data using a hospital PAS system. Funding and system incompatibility were the main reasons cited for the lack of electronic audit setup. Currently, eight separate hospital IT patient administration systems are used across 14 health boards in Scotland. Revalidation is set to commence in 2012. The Royal College of Ophthalmologists will use cataract outcome audit as a tool to ensure surgical competency for the process. Retrospective manual auditing of cataract outcome is time consuming, and can be avoided with an electronic system. Scottish ophthalmologists view revalidation with scepticism and appear to have inadequate knowledge of the process. However, they strongly agree with the concept of cataract surgery audit. The existing and future electronic applications that may support surgical audit are commercial electronic records, web-based applications, centrally funded software applications, and robust NHS connections between community and hospital.

Willingness to Pay for Cataract Surgery Provided by a Senior Surgeon in Urban Southern China

PubMed Central

Lin, Xianhua; Ling, Yunlan; Lin, Xiaofeng; Li, Mingge; Lamoureux, Ecosse; Zheng, Yingfeng

2015-01-01

Purpose To study willingness to pay for cataract surgery and surgical service provided by a senior cataract surgeon in urban Southern China. Methods This study was a cross-sectional willingness-to-pay (WTP) interview using bidding formats. Two-hundred eleven persons with presenting visual impairment in either eye due to cataract were enrolled at a tertiary eye hospital. Participants underwent a comprehensive eye examination and a WTP interview for both surgery and service provided by a senior surgeon. Demographic information, socioeconomic status and clinical data were recorded. Results Among 211 (98% response rate) persons completing the interview, 53.6% were women and 80.6% were retired. About 72.2% had a monthly income lower than 1000 renminbi (US $161). A total of 189 (89.6%) were willing to pay for cataract and the median amount of WTP was 6000 renminbi (US$968). And 102 (50.7%) were willing to pay additional fees for surgery performed by a senior surgeon, and the median amount of WTP was 500 renminbi (US$81). In regression models adjusting for age and gender, persons with preexisting eye diseases other than cataract, were more likely to pay for cataract surgery and service provided by a senior surgeon (P = 0.04 for both). Conclusions In urban China, cataract patients, especially those with preexisting eye conditions, are willing to pay additional fees for a senior surgeon. Moving to a system where the price of cataract surgery is proportional to the consultant’ skill and expertise is possible and may have a potential impact on waiting list and quality of eye care. Further studies are needed to examine the impact of such pricing system on attitudes and choices of cataract patients. PMID:26575284

Nuclear Cataract Shows Significant Familial Aggregation in an Older Population after Adjustment for Possible Shared Environmental Factors

PubMed Central

Congdon, Nathan; Broman, Karl W.; Lai, Hong; Munoz, Beatriz; Bowie, Heidi; Gilber, Donna; Wojciechowski, Robert; Alston, Christine; West, Sheila K.

2011-01-01

Purpose To quantify the association between siblings in age-related nuclear cataract, after adjusting for known environmental and personal risk factors. Methods All participants (probands) in the Salisbury Eye Evaluation (SEE) project and their locally resident siblings underwent digital slit lamp photography and were administered a questionnaire to assess risk factors for cataract including: age, gender, lifetime sun exposure, smoking and diabetes history, and use of alcohol and medications such as estrogens and steroids. In addition, blood pressure, body mass index, and serum antioxidants were measured in all participants. Lens photographs were graded by trained observers masked to the subjects' identity, using the Wilmer Cataract Grading System. The odds ratio for siblings for affectedness with nuclear cataract and the sibling correlation of nuclear cataract grade, after adjusting for covariates, were estimated with generalized estimating equations. Results Among 307 probands (mean age, 77.6 ± 4.5 years) and 434 full siblings (mean age, 72.4 ± 7.4 years), the average sibship size was 2.7 per family. After adjustment for covariates, the probability of development of nuclear cataract was significantly increased (odds ratio [OR] = 2.07, 95% confidence interval [CI], 1.30–3.30) among individuals with a sibling with nuclear cataract (nuclear grade ≥ 3.0). The final fitted model indicated a magnitude of heritability for nuclear cataract of 35.6% (95% CI: 21.0%–50.3%) after adjustment for the covariates. Conclusions Findings in this study are consistent with a genetic effect for age-related nuclear cataract, a common and clinically significant form of lens opacity. PMID:15223793

Enhancement and restoration of non-uniform illuminated Fundus Image of Retina obtained through thin layer of cataract.

PubMed

Mitra, Anirban; Roy, Sudipta; Roy, Somais; Setua, Sanjit Kumar

2018-03-01

Retinal fundus images are extensively used in manually or without human intervention to identify and analyze various diseases. Due to the comprehensive imaging arrangement, there is a large radiance, reflectance and contrast inconsistency within and across images. A novel method is proposed based on the cataract physical model to reduce the generated blurriness of the fundus image at the time of image acquisition through the thin layer of cataract by the fundus camera. After the blurriness reduction the method is proposed the enhancement procedure of the images with an objective on contrast perfection with no preamble of artifacts. Due to the uneven distribution of thickness of the cataract, the cataract surroundings are first predicted in the domain of frequency. Second, the resultant image of first step enhanced by the intensity histogram equalization in the adapted Hue Saturation Intensity (HSI) color image space such as the gamut problem can be avoided. The concluding image with suitable color and disparity is acquired by using the proposed max-min color correction approach. The result indicates that not only the proposed method can more effectively enhanced the non-uniform image of retina obtain through thin layer of cataract, but also the resulting image show appropriate brightness and saturation and maintain complete color space information. The projected enhancement method has been tested on the openly available datasets and the result evaluated with the standard used image enhancement algorithms and the cataract removal method. Results show noticeable development over existing methods. Cataract often prevents the clinician from objectively evaluating fundus feature. Cataract also affect subjective test. Enhancement and restoration of non-uniform illuminated Fundus Image of Retina obtained through thin layer of Cataract has shown here to be potentially beneficial. Copyright © 2018 Elsevier B.V. All rights reserved.

Amyloid β1-43 Accumulates in the Lens Epithelium of Cortical Opacification in Japanese Patients.

PubMed

Nagai, Noriaki; Mano, Yu; Otake, Hiroko; Shibata, Teppei; Kubo, Eri; Sasaki, Hiroshi

2017-06-01

We investigated the accumulation of amyloid β (Aβ1-40, Aβ1-42, Aβ1-43) in the lens epithelium of patients with opacification of five different types (cortical cataract [COR]; nuclear cataract [NUC]; posterior subcapsular cataract [PSC]; retrodots [RD]; and water clefts [WC]). Samples were collected from Japanese patients taken during cataract surgery; Aβ levels and mRNA expression were determined by ELISA and a real-time RT-PCR method, respectively. Levels of Aβ1-40 and Aβ1-42 in the lens epithelium of patients with COR, NUC, PSC, RD, and WC showed no significant differences in comparison with transparent lens epithelium. Levels of Aβ1-43 in the lens epithelium of patients with PSC and WC were not detected, and NUC and RD were slightly elevated. In contrast to the results in these cataract types, high Aβ1-43 levels were observed in the lens epithelium of patients with COR, and a close relationship was observed between Aβ1-43 levels and the degree of lens opacification (R = 0.8229, n = 6). The levels of Aβ1-43 were also higher in the lens epithelium of patients with mixed-cataract showing cortical opacification, and the Aβ1-43 levels in the lens epithelium of mixed-cataract patients with cortical opacification was significantly higher than in that of mixed-cataract patients without cortical opacification. In addition, the level of an amyloid precursor protein mRNA in the lens epithelium of mixed-cataract patients with cortical opacification was significantly higher than in transparent lens and mixed-cataract patients without cortical opacification. We found high levels of Aβ1-43 accumulation in the lens epithelium of Japanese patients with cortical opacification.

Indication for cataract surgery. Do we have evidence of who will benefit from surgery? A systematic review and meta-analysis.

PubMed

Kessel, Line; Andresen, Jens; Erngaard, Ditte; Flesner, Per; Tendal, Britta; Hjortdal, Jesper

2016-02-01

The need for cataract surgery is expected to rise dramatically in the future due to the increasing proportion of elderly citizens and increasing demands for optimum visual function. The aim of this study was to provide an evidence-based recommendation for the indication of cataract surgery based on which group of patients are most likely to benefit from surgery. A systematic literature search was performed in the MEDLINE, CINAHL, EMBASE and COCHRANE LIBRARY databases. Studies evaluating the outcome after cataract surgery according to preoperative visual acuity and visual complaints were included in a meta-analysis. We identified eight observational studies comparing outcome after cataract surgery in patients with poor (<20/40) and fair (>20/40) preoperative visual acuity. We could not find any studies that compared outcome after cataract surgery in patients with few or many preoperative visual complaints. A meta-analysis showed that the outcome of cataract surgery, evaluated as objective and subjective visual improvement, was independent on preoperative visual acuity. There is a lack of scientific evidence to guide the clinician in deciding which patients are most likely to benefit from surgery. To overcome this shortage of evidence, many systems have been developed internationally to prioritize patients on waiting lists for cataract surgery, but the Swedish NIKE (Nationell Indikationsmodell för Katarakt Ekstraktion) is the only system where an association to the preoperative scoring of a patient has been related to outcome of cataract surgery. We advise that clinicians are inspired by the NIKE system when they decide which patients to operate to ensure that surgery is only offered to patients who are expected to benefit from cataract surgery. © 2015 The Authors. Acta Ophthalmologica published by John Wiley & Sons Ltd on behalf of Acta Ophthalmologica Scandinavica Foundation.

Willingness to Pay for Cataract Surgery Provided by a Senior Surgeon in Urban Southern China.

PubMed

Wang, Mei; Zuo, Yajing; Lin, Xianhua; Ling, Yunlan; Lin, Xiaofeng; Li, Mingge; Lamoureux, Ecosse; Zheng, Yingfeng

2015-01-01

To study willingness to pay for cataract surgery and surgical service provided by a senior cataract surgeon in urban Southern China. This study was a cross-sectional willingness-to-pay (WTP) interview using bidding formats. Two-hundred eleven persons with presenting visual impairment in either eye due to cataract were enrolled at a tertiary eye hospital. Participants underwent a comprehensive eye examination and a WTP interview for both surgery and service provided by a senior surgeon. Demographic information, socioeconomic status and clinical data were recorded. Among 211 (98% response rate) persons completing the interview, 53.6% were women and 80.6% were retired. About 72.2% had a monthly income lower than 1000 renminbi (US $161). A total of 189 (89.6%) were willing to pay for cataract and the median amount of WTP was 6000 renminbi (US$968). And 102 (50.7%) were willing to pay additional fees for surgery performed by a senior surgeon, and the median amount of WTP was 500 renminbi (US$81). In regression models adjusting for age and gender, persons with preexisting eye diseases other than cataract, were more likely to pay for cataract surgery and service provided by a senior surgeon (P = 0.04 for both). In urban China, cataract patients, especially those with preexisting eye conditions, are willing to pay additional fees for a senior surgeon. Moving to a system where the price of cataract surgery is proportional to the consultant' skill and expertise is possible and may have a potential impact on waiting list and quality of eye care. Further studies are needed to examine the impact of such pricing system on attitudes and choices of cataract patients.

Clinical study on evaluation of anti-cataract effect of Triphaladi Ghana Vati and Elaneer Kuzhambu Anjana in Timira (immature cataract).

PubMed

Bhati, Hitesh; Manjusha, R

2015-01-01

Senile cataract is the leading cause of blindness according to the World Health Report, 1998. Till date no accepted medical treatment is available for cataract. In Ayurveda visual disturbances are described in the context of Timira, Kacha and Linganasha. Timira is an early stage characterized by blurring of vision and Linganasha is end stage where complete loss of vision occurs. Ancient scholars have advocated different Anjana application and oral medications in the Timira and Kacha stage. To study the efficacy of test drugs Triphaladi Ghana Vati and Elaneer Kuzhambu Anjana in immature cataract. In this trial patients having Senile Immature Cataract were randomized with equal probability to one of the two treatment Groups A and B (n = 20 each). In Group A Triphaladi Ghana Vati 500 mg internally for 3 months and in Group B Triphaladi Ghana Vati 500 mg internally and Elaneer Kuzhambu Anjana for local application were given. Assessment was done on the basis of blurring of vision, visualization of nonexisting things, difficulty in bright light and dim light or night vision, distant visual acuity, pinhole vision, best corrected visual acuity and cataract grading on slit lamp. Both groups showed statistically significant changes in blurring of vision, difficulty in glare, daytime and bright light, distant visual activity, pinhole vision, and best-corrected visual acuity. Group B also showed significant changes in difficulty in night time, visualization of nonexisting things and in nuclear cataract. The study establishes that test drugs can reduce and control the progress of immature cataract, and combined therapy was found more effective. Chakshushya Rasayana, early diagnosis and proper management on Doshic lines can prevent arrest or delay senile cataract.

Clinical study on evaluation of anti-cataract effect of Triphaladi Ghana Vati and Elaneer Kuzhambu Anjana in Timira (immature cataract)

PubMed Central

Bhati, Hitesh; Manjusha, R.

2015-01-01

Introduction: Senile cataract is the leading cause of blindness according to the World Health Report, 1998. Till date no accepted medical treatment is available for cataract. In Ayurveda visual disturbances are described in the context of Timira, Kacha and Linganasha. Timira is an early stage characterized by blurring of vision and Linganasha is end stage where complete loss of vision occurs. Ancient scholars have advocated different Anjana application and oral medications in the Timira and Kacha stage. Aim: To study the efficacy of test drugs Triphaladi Ghana Vati and Elaneer Kuzhambu Anjana in immature cataract. Materials and Methods: In this trial patients having Senile Immature Cataract were randomized with equal probability to one of the two treatment Groups A and B (n = 20 each). In Group A Triphaladi Ghana Vati 500 mg internally for 3 months and in Group B Triphaladi Ghana Vati 500 mg internally and Elaneer Kuzhambu Anjana for local application were given. Assessment was done on the basis of blurring of vision, visualization of nonexisting things, difficulty in bright light and dim light or night vision, distant visual acuity, pinhole vision, best corrected visual acuity and cataract grading on slit lamp. Results: Both groups showed statistically significant changes in blurring of vision, difficulty in glare, daytime and bright light, distant visual activity, pinhole vision, and best-corrected visual acuity. Group B also showed significant changes in difficulty in night time, visualization of nonexisting things and in nuclear cataract. Conclusion: The study establishes that test drugs can reduce and control the progress of immature cataract, and combined therapy was found more effective. Chakshushya Rasayana, early diagnosis and proper management on Doshic lines can prevent arrest or delay senile cataract. PMID:27313415

Hereditary pediatric cataract on the Arabian Peninsula

PubMed Central

Khan, Arif O.

2011-01-01

Hereditary pediatric cataract on the Arabian Peninsula does not follow the same epidemiological patterns as described for Western populations. This article describes selected genetic causes for inherited pediatric cataract in the region. PMID:23960971

Pediatric cataract

PubMed Central

Khokhar, Sudarshan Kumar; Pillay, Ganesh; Dhull, Chirakshi; Agarwal, Esha; Mahabir, Manish; Aggarwal, Pulak

2017-01-01

Pediatric cataract is a leading cause of childhood blindness. Untreated cataracts in children lead to tremendous social, economical, and emotional burden to the child, family, and society. Blindness related to pediatric cataract can be treated with early identification and appropriate management. Most cases are diagnosed on routine screening whereas some may be diagnosed after the parents have noticed leukocoria or strabismus. Etiology of pediatric cataract is varied and diagnosis of specific etiology aids in prognostication and effective management. Pediatric cataract surgery has evolved over years, and with improving knowledge of myopic shift and axial length growth, outcomes of these patients have become more predictable. Favorable outcomes depend not only on effective surgery, but also on meticulous postoperative care and visual rehabilitation. Hence, it is the combined effort of parents, surgeons, anesthesiologists, pediatricians, and optometrists that can make all the difference. PMID:29208814

Paediatric cataract blindness in the developing world: surgical techniques and intraocular lenses in the new millennium

PubMed Central

Wilson, M E; Pandey, S K; Thakur, J

2003-01-01

Paediatric cataract blindness presents an enormous problem to developing countries in terms of human morbidity, economic loss, and social burden. Managing cataracts in children remains a challenge: treatment is often difficult, tedious, and requires a dedicated team effort. To assure the best long term outcome for cataract blind children, appropriate paediatric surgical techniques need to be defined and adopted by ophthalmic surgeons of developing countries. The high cost of operative equipment and the uneven world distribution of ophthalmologists, paediatricians, and anaesthetists create unique challenges. This review focuses on issues related to paediatric cataract management that are appropriate and suitable for ophthalmic surgeons in the developing world. Practical guidelines and recommendations have also been provided for ophthalmic surgeons and health planners dealing with childhood cataract management in the developing world. PMID:12488254

EPHA2 Polymorphisms in Estonian Patients with Age-Related Cataract.

PubMed

Celojevic, Dragana; Abramsson, Alexandra; Seibt Palmér, Mona; Tasa, Gunnar; Juronen, Erkki; Zetterberg, Henrik; Zetterberg, Madeleine

2016-01-01

Ephrin receptors (Ephs) are tyrosine kinases that together with their ligands, ephrins, are considered important in cell-cell communication, especially during embryogenesis but also for epithelium homeostasis. Studies have demonstrated the involvement of mutations or common variants of the gene encoding Eph receptor A2 (EPHA2), in congenital cataract and in age-related cataract. This study investigated a number of disease-associated single nucleotide polymorphisms (SNPs) in EPHA2 in patients with age-related cataract. The study included 491 Estonian patients who had surgery for age-related cataract, classified as nuclear, cortical, posterior subcapsular and mixed lens opacities, and 185 controls of the same ethnical origin. Seven SNPs in EPHA2 (rs7543472, rs11260867, rs7548209, rs3768293, rs6603867, rs6678616, rs477558) were genotyped using TaqMan Allelic Discrimination. Statistical analyses for single factor associations used χ(2)-test and logistic regression was performed including relevant covariates (age, sex and smoking). In single-SNP allele analysis, only the rs7543472 showed a borderline significant association with risk of cataract (p = 0.048). Regression analysis with known risk factors for cataract showed no significant associations of the studied SNPs with cataract. Stratification by cataract subtype did not alter the results. Adjusted odds ratios were between 0.82 and 1.16 (95% confidence interval 0.61-1.60). The present study does not support a major role of EphA2 in cataractogenesis in an Estonian population.

Simultaneous vs sequential bilateral cataract surgery for infants with congenital cataracts: Visual outcomes, adverse events, and economic costs.

PubMed

Dave, Hreem; Phoenix, Vidya; Becker, Edmund R; Lambert, Scott R

2010-08-01

To compare the incidence of adverse events and visual outcomes and to compare the economic costs of sequential vs simultaneous bilateral cataract surgery for infants with congenital cataracts. Retrospective review of simultaneous vs sequential bilateral cataract surgery for infants with congenital cataracts who underwent cataract surgery when 6 months or younger at our institution. Records were available for 10 children who underwent sequential surgery at a mean age of 49 days for the first eye and 17 children who underwent simultaneous surgery at a mean age of 68 days (P = .25). We found a similar incidence of adverse events between the 2 treatment groups. Intraoperative or postoperative complications occurred in 14 eyes. The most common postoperative complication was glaucoma. No eyes developed endophthalmitis. The mean (SD) absolute interocular difference in logMAR visual acuities between the 2 treatment groups was 0.47 (0.76) for the sequential group and 0.44 (0.40) for the simultaneous group (P = .92). Payments for the hospital, drugs, supplies, and professional services were on average 21.9% lower per patient in the simultaneous group. Simultaneous bilateral cataract surgery for infants with congenital cataracts is associated with a 21.9% reduction in medical payments and no discernible difference in the incidence of adverse events or visual outcomes. However, our small sample size limits our ability to make meaningful comparisons of the relative risks and visual benefits of the 2 procedures.

A Comparison of Endothelial Cell Loss in Combined Cataract and MIGS (Hydrus) Procedure to Phacoemulsification Alone: 6-Month Results

PubMed Central

Fea, Antonio M.; Consolandi, Giulia; Pignata, Giulia; Cannizzo, Paola Maria Loredana; Lavia, Carlo; Billia, Filippo; Rolle, Teresa; Grignolo, Federico M.

2015-01-01

Purpose. To compare the corneal endothelial cell loss after phacoemulsification, alone or combined with microinvasive glaucoma surgery (MIGS), in nonglaucomatous versus primary open angle glaucoma (POAG) eyes affected by age-related cataract. Methods. 62 eyes of 62 patients were divided into group 1 (n = 25, affected by age-related cataract) and group 2 (n = 37, affected by age-related cataract and POAG). All patients underwent cataract surgery. Group 2 was divided into subgroups A (n = 19, cataract surgery alone) and B (n = 18, cataract surgery and MIGS). Prior to and 6 months after surgery the patients' endothelium was studied. Main outcomes were CD (cell density), SD (standard deviation), CV (coefficient of variation), and 6A (hexagonality coefficient) variations after surgeries. Results. There were no significant differences among the groups concerning preoperative endothelial parameters. The differences in CD before and after surgery were significant in all groups: 9.1% in group 1, 17.24% in group 2A, and 11.71% in group 2B. All endothelial parameters did not significantly change after surgery. Conclusions. Phacoemulsification determined a loss of endothelial cells in all groups. After surgery the change in endothelial parameters after MIGS was comparable to the ones of patients who underwent cataract surgery alone. PMID:26664740

Macroeconomic landscape of refractive surgery in the United States.

PubMed

Corcoran, Kevin J

2015-07-01

This review examines the economic history of refractive surgery and the decline of laser-assisted in-situ keratomileusis (LASIK) in the USA, and the emergence of refractive cataract surgery as an area of growth. Since it peaked in 2007 at 1.4 million procedures per year, LASIK has declined 50% in the USA, whereas refractive cataract surgery, including presbyopia-correcting intraocular lenses (IOLs), astigmatism-correcting IOLs, and femtosecond laser-assisted cataract surgery, has grown to 350 000 procedures per year, beginning in 2003. Patients are price-sensitive and responsive to publicity (good or bad) about refractive surgery and refractive cataract surgery. LASIK's decline has been partially offset by the emergence of refractive cataract surgery. About 11% of all cataract surgery in the USA involves presbyopia-correcting IOLs, astigmatism-correcting IOLs, or a femtosecond laser. From the surgeon's perspective, there are high barriers to entry into the marketplace for refractive surgery and refractive cataract surgery due to the high capital cost of excimer and femtosecond lasers, the high skill level required to deliver spectacular results to demanding patients who pay out of pocket, and the necessity to perform a high volume of surgeries to satisfy both of these requirements. Probably, less than 7% of US cataract surgeons can readily meet all of these requirements.

[Pay attention to the complexity of cataract surgery of no vitreous eyes].

PubMed

Bao, Y Z

2017-04-11

With wide-spread performance of pars plana vitrectomy, cataract surgeries with no vitreous are getting more and more. This kind of surgery has great difference between individuals and it lacks randomized large sample clinical trial. Surgical strategy decision was basically relied on the surgeon's personal experience. We should fully aware the individual and common characteristics of no vitreous cataract surgery. Surgical time should be carefully decided. Complete ocular examination, evaluation, design of cataract surgical procedure and appropriate intra-ocular lens selection are needed. We must pay highly attention on the cataract surgery of no vitreous eyes. (Chin J Ophthalmol, 2017, 53: 241-243) .

Resident and young physician experience with complex cataract surgery and new cataract and refractive technology: Results of the ASCRS 2016 Young Eye Surgeons survey.

PubMed

Schallhorn, Julie M; Ciralsky, Jessica B; Yeu, Elizabeth

2017-05-01

A survey was offered to attendees of the 2016 annual meeting of the American Society of Cataract and Refractive Surgery (ASCRS) as well as online to ASCRS members. Of the 429 self-identified surgeons in training or those with fewer than 5 years in practice, 83% had performed complex cataract surgery using iris expansion devices or capsular tension rings (63%) and 70% had implanted a toric intraocular lens (IOL). A minority of respondents had performed laser-assisted cataract surgery (27%) or implanted presbyopia-correcting IOLs (39%), and only half (50%) had performed laser vision correction (LVC). Comfort with complex cataract and IOL procedures improved with increasing number of cases performed until greater than 10 cases. From this we can conclude that young surgeons have adequate exposure to complex cataracts but lack experience in refractive surgery and new IOL technology. Reported surgeon confidence improved with increased experience and exposure. Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Glaucoma and cataract surgery: two roads merging into one.

PubMed

Shah, Manjool; Law, Geoffrey; Ahmed, Iqbal Ike K

2016-01-01

To discuss the increasing utilization of cataract extraction in the management of glaucoma and to highlight advances in surgical care that can promote synergistic treatment of these comorbid conditions. Recent years have demonstrated significant advances in the management of glaucoma through the use of novel microinvasive glaucoma devices. Furthermore, an increased understanding of the role of cataract surgery in the treatment of various glaucomas warrants review. Nevertheless, cataract surgery in the glaucoma patient warrants specific preoperative, intraoperative, and postoperative planning to optimize visual function and quality of life while mitigating potential risk factors for adverse events. Although the challenges of performing cataract extraction on glaucoma patients exist, the potential benefit to these patients is substantial. With attention to pre- and perioperative surgical planning and intraoperative technique, as well as with awareness and potential utilization of novel devices and treatment strategies, cataract extraction offers a unique platform for anatomical and functional improvement in this increasingly common cohort of patients.

Incidence of environmental and genetic factors causing congenital cataract in Children of Lahore.

PubMed

Naz, Shagufta; Sharif, Saima; Badar, Hafsa; Rashid, Farzana; Kaleem, Afshan; Iqtedar, Mehwish

2016-07-01

To check the incidence of environmental and genetic factors causing congenital cataract in infants. The descriptive study was conducted at Layton Rahmatullah Benevolent Trust, Lahore, Pakistan, from October 2013 to April 2014, and comprised children under 15 years of age who had rubella syndrome, herpes simplex, birth trauma, trisomy 21, Nance-Horan syndrome or Lowe's syndrome. Of the 38,000 cases examined, 120(0.3%) patients were diagnosed with congenital cataract. Of them, 52(43.33%)were aged between 2 and 5 years,22(18.33%) <11 years and 10(8.33%) ?15 years. Bilateral congenital cataract was observed in 91(75.83%) patients and unilateral congenital cataract in 29(24.17%). Environmental factors caused 72(62.07%) cases and genetic factors caused 44(37.93%).. Congenital cataract predominated in boys compared to girls. Early diagnosis and adequate therapy requires specific technology, as well as long-term and permanent care..

Bacterial endophthalmitis after resident-performed cataract surgery.

PubMed

Hollander, David A; Vagefi, M Reza; Seiff, Stuart R; Stewart, Jay M

2006-05-01

To determine if there is an increased rate of postoperative bacterial endophthalmitis after resident-performed cataract extraction relative to the reported rates of experienced surgeons. Retrospective, observational case series. The operative reports of the resident-performed cataract surgeries at San Francisco General Hospital between 1983 and 2002 were reviewed. Cases of culture-positive bacterial endophthalmitis and vitreous loss were identified. Between 1983 and 2002, three cases (0.11%) of culture-positive bacterial endophthalmitis occurred after 2718 resident-performed cataract extractions. The overall vitreous loss rate was 6.7%. Two endophthalmitis cases were acute (Staphylococcus epidermidis, Streptococcus viridans), presenting within five days of surgeries complicated by vitreous loss, and one case was delayed-onset (Corynebacterium species) after Nd:YAG posterior capsulotomy after uncomplicated cataract extraction. Despite higher rates of vitreous loss, the rate of endophthalmitis following resident-performed cataract surgery remains comparable with the rates of more experienced surgeons.

Rapid assessment of cataract surgical coverage in rural Zululand.

PubMed

Rotchford, A P; Johnson, G J

2000-10-01

Cataract surgical coverage (CSC) is a useful indicator of the degree of success of a cataract intervention programme. However, because previously described methods are time-consuming and labour-intensive, they are rarely performed. This study describes a simple and inexpensive assessment of CSC based on screening of pensioners at pension delivery sites in a rural district. Random cluster-based cross-sectional survey. State pension distribution sites in Hlabisa, a rural district in KwaZulu-Natal, South Africa. 562 old-age pensioners. Subjects found to be blind (visual acuity < 3/60) and those reporting a history of eye surgery were examined using a torch and direct ophthalmoscope by an ophthalmologist. Cases of blindness due to operable cataract and post-cataract surgical subjects were identified. CSC was found to be 38.5% (95% confidence interval 29.1-47.9%). Blindness prevalence was 10.3%, with 69.0% due to cataract.

Nutritional modulation of cataract

PubMed Central

Weikel, Karen A; Garber, Caren; Baburins, Alyssa; Taylor, Allen

2014-01-01

Lens opacification or cataract reduces vision in over 80 million people worldwide and blinds 18 million. These numbers will increase dramatically as both the size of the elderly demographic and the number of those with carbohydrate metabolism-related problems increase. Preventative measures for cataract are critical because the availability of cataract surgery in much of the world is insuficient. Epidemiologic literature suggests that the risk of cataract can be diminished by diets that are optimized for vitamin C, lutein/zeaxanthin, B vitamins, omega-3 fatty acids, multivitamins, and carbohydrates: recommended levels of micronutrients are salutary. The limited data from intervention trials provide some support for observational studies with regard to nuclear – but not other types of – cataracts. Presented here are the beneficial levels of nutrients in diets or blood and the total number of participants surveyed in epidemiologic studies since a previous review in 2007. PMID:24279748

Oxidative stress markers in aqueous humor of patients with senile cataracts.

PubMed

Sawada, Hideko; Fukuchi, Takeo; Abe, Haruki

2009-01-01

To investigate the levels of oxidative stress markers in human eyes with senile cataracts. We conducted a retrospective, case-controlled study of 57 patients with senile cataracts. To assess oxidative stress markers in the eye, we measured the enzymatic activities of superoxide dismutase (SOD) and catalase (CAT) as well as the total protein levels in aqueous humor. In aqueous humor, SOD and CAT activity levels were 0.133 +/- 0.020 and 1.223 +/- 0.081 U/ml, respectively; protein levels were 2.372 +/- 0.166 mg/ml (means +/- SEM). We observed a significant increase in SOD activity and the protein level in progressed nuclear cataracts. No significant age-associated difference in antioxidant enzyme levels was detected. Significant increases in the levels of SOD activity and total protein correlated with the severity of the cataract but not with patient age, suggesting that progressed cataract is associated with molecules leaking from the lens capsule.

The Effect of a Mediterranean Diet on the Incidence of Cataract Surgery.

PubMed

García-Layana, Alfredo; Ciufo, Gianfranco; Toledo, Estefania; Martínez-González, Miguel A; Corella, Dolores; Fitó, Montse; Estruch, Ramon; Gómez-Gracia, Enrique; Fiol, Miguel; Lapetra, José; Serra-Majem, Lluís; Pintó, Xavier; Portillo, Maria P; Sorli, José V; Bulló, Mónica; Vinyoles, Ernest; Sala-Vila, Aleix; Ros, Emilio; Salas-Salvadó, Jordi; Arós, Fernando

2017-05-03

Cataract is a leading cause of vision impairment worldwide, and surgery is the only available treatment. The process that initiates lens opacification is dependent on the oxidative stress experienced by the lens components. A healthy overall dietary pattern, with the potential to reduce oxidative stress, has been suggested as a means to decrease the risk of developing cataract. We aimed to investigate the hypothesis that an intervention with a Mediterranean diet (MedDiet) rather than a low-fat diet could decrease the incidence of cataract surgery in elderly subjects. We included 5802 men and women (age range: 55-80 years) from the Prevención con Dieta Mediterránea study (multicenter, parallel-group, randomized controlled clinical trial) who had not undergone cataract surgery. They were randomly assigned to one of three intervention groups: (1) a MedDiet enriched with extra-virgin olive oil (EVOO) ( n = 1998); (2) a MedDiet enriched with nuts ( n = 1914), and a control group recommended to follow a low-fat diet ( n = 1890). The incidence of cataract surgery was recorded yearly during follow-up clinical evaluations. Primary analyses were performed on an intention-to-treat basis. Cox regression analyses were used to assess the relationship between the nutritional intervention and the incidence of cataract surgery. During a follow-up period of 7.0 years (mean follow-up period: 5.7 years; median: 5.9 years), 559 subjects underwent cataract surgery. Two hundred and six participants from the MedDiet + EVOO group, 174 from the MedDiet + Nuts group, and 179 from the control group underwent cataract surgery. We did not observe a reduction in the incidence of cataract surgery in the MedDiet groups compared to the control group. The multivariable adjusted hazard ratios were 1.03 (95% confidence interval [CI]: 0.84-1.26, p = 0.79) for the control group versus the MedDiet + EVOO group and 1.06 (95% CI: 0.86-1.31, p = 0.58) for the control group versus the MedDiet + Nuts group. To our knowledge, this is the first large randomized trial assessing the role of a MedDiet on the incidence of cataract surgery. Our results showed that the incidence of cataract surgery was similar in the MedDiet with EVOO, MedDiet with nuts, and low-fat diet groups. Further studies are necessary to investigate whether a MedDiet could have a preventive role in cataract surgery.

The Effect of a Mediterranean Diet on the Incidence of Cataract Surgery

PubMed Central

García-Layana, Alfredo; Ciufo, Gianfranco; Toledo, Estefania; Martínez-González, Miguel A.; Corella, Dolores; Fitó, Montse; Estruch, Ramon; Gómez-Gracia, Enrique; Fiol, Miguel; Lapetra, José; Serra-Majem, Lluís; Pintó, Xavier; Portillo, Maria P.; Sorli, José V.; Bulló, Mónica; Vinyoles, Ernest; Sala-Vila, Aleix; Ros, Emilio; Salas-Salvadó, Jordi; Arós, Fernando

2017-01-01

Background: Cataract is a leading cause of vision impairment worldwide, and surgery is the only available treatment. The process that initiates lens opacification is dependent on the oxidative stress experienced by the lens components. A healthy overall dietary pattern, with the potential to reduce oxidative stress, has been suggested as a means to decrease the risk of developing cataract. We aimed to investigate the hypothesis that an intervention with a Mediterranean diet (MedDiet) rather than a low-fat diet could decrease the incidence of cataract surgery in elderly subjects. Methods: We included 5802 men and women (age range: 55–80 years) from the Prevención con Dieta Mediterránea study (multicenter, parallel-group, randomized controlled clinical trial) who had not undergone cataract surgery. They were randomly assigned to one of three intervention groups: (1) a MedDiet enriched with extra-virgin olive oil (EVOO) (n = 1998); (2) a MedDiet enriched with nuts (n = 1914), and a control group recommended to follow a low-fat diet (n = 1890). The incidence of cataract surgery was recorded yearly during follow-up clinical evaluations. Primary analyses were performed on an intention-to-treat basis. Cox regression analyses were used to assess the relationship between the nutritional intervention and the incidence of cataract surgery. Results: During a follow-up period of 7.0 years (mean follow-up period: 5.7 years; median: 5.9 years), 559 subjects underwent cataract surgery. Two hundred and six participants from the MedDiet + EVOO group, 174 from the MedDiet + Nuts group, and 179 from the control group underwent cataract surgery. We did not observe a reduction in the incidence of cataract surgery in the MedDiet groups compared to the control group. The multivariable adjusted hazard ratios were 1.03 (95% confidence interval [CI]: 0.84–1.26, p = 0.79) for the control group versus the MedDiet + EVOO group and 1.06 (95% CI: 0.86–1.31, p = 0.58) for the control group versus the MedDiet + Nuts group. Conclusions: To our knowledge, this is the first large randomized trial assessing the role of a MedDiet on the incidence of cataract surgery. Our results showed that the incidence of cataract surgery was similar in the MedDiet with EVOO, MedDiet with nuts, and low-fat diet groups. Further studies are necessary to investigate whether a MedDiet could have a preventive role in cataract surgery. PMID:28467363

Three-Dimensional Cataract Crystalline Lens Imaging With Swept-Source Optical Coherence Tomography.

PubMed

de Castro, Alberto; Benito, Antonio; Manzanera, Silvestre; Mompeán, Juan; Cañizares, Belén; Martínez, David; Marín, Jose María; Grulkowski, Ireneusz; Artal, Pablo

2018-02-01

To image, describe, and characterize different features visible in the crystalline lens of older adults with and without cataract when imaged three-dimensionally with a swept-source optical coherence tomography (SS-OCT) system. We used a new SS-OCT laboratory prototype designed to enhance the visualization of the crystalline lens and imaged the entire anterior segment of both eyes in two groups of participants: patients scheduled to undergo cataract surgery, n = 17, age range 36 to 91 years old, and volunteers without visual complains, n = 14, age range 20 to 81 years old. Pre-cataract surgery patients were also clinically graded according to the Lens Opacification Classification System III. The three-dimensional location and shape of the visible opacities were compared with the clinical grading. Hypo- and hyperreflective features were visible in the lens of all pre-cataract surgery patients and in some of the older adults in the volunteer group. When the clinical examination revealed cortical or subcapsular cataracts, hyperreflective features were visible either in the cortex parallel to the surfaces of the lens or in the posterior pole. Other type of opacities that appeared as hyporeflective localized features were identified in the cortex of the lens. The OCT signal in the nucleus of the crystalline lens correlated with the nuclear cataract clinical grade. A dedicated OCT is a useful tool to study in vivo the subtle opacities in the cataractous crystalline lens, revealing its position and size three-dimensionally. The use of these images allows obtaining more detailed information on the age-related changes leading to cataract.

Factors Associated with Complications and Postoperative Visual Outcomes of Cataract Surgery; a Study of 1,632 Cases

PubMed Central

Thanigasalam, Thevi; Reddy, Sagili Chandrashekara; Zaki, Rafdzah Ahmad

2015-01-01

Purpose: Cataract surgery is the most common intraocular surgery performed all over the world and has advanced technically in recent years. As in all surgeries, complications are unavoidable. Herein we report factors associated with complications and visual outcomes of cataract surgery. Methods: This retrospective cohort study included data of 1,632 cataract surgeries performed from 2007 to 2010 which was obtained from the cataract registry of the Malaysian National Eye Database. Demographic features, ocular and systemic comorbidites, grade of surgeon expertise and duration of surgery, type of anesthesia, intraoperative and postoperative complications, and the type of intraocular lens were recorded. Best corrected visual acuities were compared before and after the operation. Results: Mean patient age was 66.9 years with equal gender distribution. The majority of subjects had age related cataracts. Phacoemulsification was done faster than other surgeries, especially by specialist surgeons. History of prior ocular surgery and operations performed under general anesthesia were associated with greater complications. Phacoemulsification was associated with less complications and better visual outcomes. The age and etiology of cataract did not affect complications. Malays, absence of ocular comorbidities, left eyes and eyes operated under local anesthesia were more likely to experience more visual improvement. Gender, age, cause of cataract, systemic comorbidities and surgeon expertise as well as intra-and postoperative complications did not affect the visual outcomes. Conclusion: Phacoemulsification had good visual outcomes in cataract surgery. Duration of surgery, expertise of the surgeon and complications did not affect the visual outcomes. PMID:27051481

Recurrent mutation in the crystallin alpha A gene associated with inherited paediatric cataract.

PubMed

Javadiyan, Shari; Craig, Jamie E; Souzeau, Emmanuelle; Sharma, Shiwani; Lower, Karen M; Pater, John; Casey, Theresa; Hodson, Trevor; Burdon, Kathryn P

2016-02-11

Cataract is a major cause of childhood blindness worldwide. The purpose of this study was to determine the genetic cause of paediatric cataract in a South Australian family with a bilateral lamellar paediatric cataract displaying variable phenotypes. Fifty-one genes implicated in congenital cataract in human or mouse were sequenced in an affected individual from an Australian (Caucasian) family using a custom Ampliseq library on the Ion Torrent Personal Genome Machine. Reads were mapped against the human genome (hg19) and variants called with the Torrent Suite software. Variants were annotated to dbSNP 137 using Ion Reporter (IR 1.6.2) and were prioritised for validation if they were novel or rare and were predicted to be protein changing. We identified a previously reported oligomerization disrupting mutation, c.62G > A (p.R21Q), in the Crystallin alpha A (CRYAA) gene segregating in this three generation family. No other novel or rare coding mutations were detected in the known cataract genes sequenced. Microsatellite markers were used to compare the haplotypes between the family reported here and a previously published family with the same segregating mutation. Haplotype analysis indicated a potential common ancestry between the two South Australian families with this mutation. The work strengthens the genotype-phenotype correlations between this functional mutation in the crystallin alpha A (CRYAA) gene and paediatric cataract. The p.R21Q mutation is the most likely cause of paediatric cataract in this family. The recurrence of this mutation in paediatric cataract families is likely due to a familial relationship.

[Outcome of cataract surgery in patients with pigmentary retinal degeneration].

PubMed

Grześk, Magdalena; Kałuzny, Józef; Malukiewicz-Wiśniewska, Grazyna

2007-01-01

To evaluate the results of cataract surgery in patients with RP because retinitis pigmentosa is one of the disease entities that belongs to tapeto-retinal degenerations. The occurrence of RP appearance is 1:4000 to 1:3000. Twenty patients with RP (7 women and 13 men, 33 eyes), who underwent cataract surgery were examined retrospectively. Average age in our group was 46.6 years. Visual acuity, intraocular pressure, slip lamp examination, fundus examination, cataract morphology, visual field were taken before surgery and on discharge, on the basis of medical documentation. Control examination was taken, on average, eighty one months after cataract surgery. Nine eyes were operated by phacoemulsification, 24 eyes by means of extracapsular cataract extraction. In the same way control group of 18 patients who underwent cataract surgery without RP (33 eyes) was examined. In RP group in 63.6% patients on discharge from the hospital and in 60.6% patients during the control examination, improvement of visual acuity was revealed. Deterioration was noted in 18.2% of patients on discharge from hospital and in 24.2% of patients during the control examination. In the control group improvement of visual acuity was revealed in 90.9% of patients on discharge and in 97% patients during the control examination, whereas deterioration of visual acuity occurred in 6.1% patients on discharge and in 3% patients during the check examination. In patients with retinitis pigmentosa cataract occurs earlier then in the control group. Cataract surgery for relatively minor opacities is beneficial in patients with RP, and causes improvement of visual acuity in most of eyes undergoing surgery.

A Mutation in the Start Codon of γ-Crystallin D Leads to Nuclear Cataracts in the Dahl SS/Jr-Ctr Strain

PubMed Central

Johnson, Ashley C.; Lee, Jonathan W.; Harmon, Ashlyn C.; Morris, Zaliya; Wang, Xuexiang; Fratkin, Jonathan; Rapp, John P.; Gomez-Sanchez, Elise; Garrett, Michael R.

2013-01-01

Cataracts are a major cause of blindness. The most common forms of cataracts are age and UV related and develops mostly in the elderly, while congenital cataracts appear at birth or in early childhood. The Dahl salt-sensitive (SS/Jr) rat is an extensively used model of salt-sensitive hypertension that exhibits concomitant renal disease. In the mid 1980’s, cataracts appeared in a few animals in the Dahl S colony, presumably the result of a spontaneous mutation. The mutation was fixed and bred to establish the SS/Jr-Ctr substrain. The SS/Jr-Ctr substrain has been exclusively used by a single investigator to study the role of steroids and hypertension. Using a classical positional cloning approach, we localized the cataract gene with high-resolution to a less than 1 Mbp region on chromosome 9 using an F1 (SS/Jr-Ctr X SHR) X SHR backcross population. The 1 Mbp region contained only 13 genes, including 4 genes from the γ-crystallins (Cryg) gene family which are known to play a role in cataract formation. All of the γ-crystallins were sequenced and a novel point mutation in the start codon (ATG → GTG) of the Crygd gene was identified which led to the complete absence of CRYGD protein in the eyes of the SS/Jr-Ctr strain. In summary, the identification of the genetic cause in this novel cataract model may provide an opportunity to better understand the development of cataracts, particularly in the context of hypertension. PMID:23404175

Ophthalmic nepafenac use in the Netherlands and Denmark.

PubMed

Margulis, Andrea V; Houben, Eline; Hallas, Jesper; Overbeek, Jetty A; Pottegård, Anton; Torp-Pedersen, Tobias; Perez-Gutthann, Susana; Arana, Alejandro

2017-08-01

To describe nepafenac use in the Netherlands and Denmark with reference to its approved indications. For context, we also describe the use of ketorolac and diclofenac. We identified users in the PHARMO Database Network (the Netherlands, 2008-2013) and the Danish national health registers (Denmark, 1994-2014). We described prevalence of cataract surgery and duration of use in patients with cataract surgery with and without diabetes. In the Netherlands, 9530 nepafenac users (mean age, 71 years; 60% women) contributed 12 691 therapy episodes, of which 21% had a recently recorded cataract surgery. Of 2266 episodes in adult non-diabetic patients with cataract surgery, 60% had one bottle dispensed (treatment duration ≤21 days). Of 441 episodes in adult diabetic patients with cataract surgery, 90% had up to two bottles dispensed (≤60 days). Denmark had 60 403 nepafenac users (mean age, 72 years; 58% women) and 73 648 episodes (41% had recorded cataract surgery). Of 26 649 nepafenac episodes in adult non-diabetic patients with cataract surgery, 92% had one bottle dispensed. Of 3801 episodes in adult diabetic patients with cataract surgery, 99.8% had up to two bottles dispensed. Use patterns of nepafenac, ketorolac and diclofenac were roughly similar in the Netherlands, but not in Denmark. Less than half of therapy episodes were related to cataract surgery; around 90% of episodes with surgery were within the approved duration. Underrecording of ophthalmic conditions and procedures was a challenge in this study. © 2017 The Authors Acta Ophthalmologica published by John Wiley & Sons Ltd on behalf of Acta Ophthalmologica Scandinavica Foundation.

Age-related Cataract in a Randomized Trial of Vitamins E and C in Men

PubMed Central

Christen, William G.; Glynn, Robert J.; Sesso, Howard D.; Kurth, Tobias; MacFadyen, Jean; Bubes, Vadim; Buring, Julie E.; Manson, JoAnn E.; Michael Gaziano, J.

2010-01-01

Objective To test whether supplementation with alternate day vitamin E or daily vitamin C affects the incidence of age-related cataract in a large-scale randomized trial of men. Design Randomized, double-masked, placebo-controlled trial. Participants Eleven thousand five hundred forty-five apparently healthy US male physicians aged 50 years or older who were without a diagnosis of cataract at baseline. Intervention Participants were randomly assigned to receive 400 IU of vitamin E or placebo on alternate days, and 500 mg of vitamin C or placebo daily. Main Outcome Measure Incident cataract responsible for a reduction in best-corrected visual acuity to 20/30 or worse based on self-report confirmed by medical record review. Results After 8 years of treatment and follow-up, a total of 1,174 incident cataracts were confirmed. There were 579 cataracts in the vitamin E treated group and 595 in the vitamin E placebo group (hazard ratio [HR], 0.99; 95 percent confidence interval [CI], 0.88 to 1.11). For vitamin C, there were 593 cataracts in the treated group and 581 in the placebo group (HR, 1.02; CI, 0.91 to 1.14). Conclusions In a large-scale randomized trial of US male physicians, long-term alternate day use of 400 IU of vitamin E and/or daily use of 500 mg of vitamin C had no significant beneficial or harmful effect on the risk of cataract. Application to Clinical Practice Long-term use of vitamin E and/or vitamin C supplements has no appreciable effect on cataract. PMID:21060040

Saffron administration prevents selenite-induced cataractogenesis

PubMed Central

Makri, Olga E.; Ferlemi, Anastasia-Varvara; Lamari, Fotini N.

2013-01-01

Purpose The present study sought to investigate whether Crocus sativus stigmas (saffron) extract prevents selenium-induced cataractogenesis in vivo, and to study its possible protective mechanism. Methods Wistar rat pups were randomized into three groups. Group I (control) received subcutaneous injection of normal saline on postnatal day 10. Groups II (selenite-treated) and III (selenite+saffron-treated) received subcutaneous injection of sodium selenite (20 µmol/kg body weight) on postnatal day 10. Group III also received intraperitoneal injections of saffron extract (60 mg/kg body weight) on postnatal days 9 and 12. On postpartum day 21, rats were sacrificed and the lenses were isolated and examined for cataract formation. Activities of superoxide dismutase, glutathione peroxidase, catalase, and glutathione levels, as markers of antioxidant defense, were measured in the isolated lenses. Levels of the indicator of lipid peroxidation, malondialdehyde, and protein oxidation (sulfhydryl content) in the lens were also determined. The effect of the different treatments on lens protein profile was evaluated through an estimation of the soluble to insoluble protein ratio and sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis of the water-soluble fraction (WSF) of lens proteins. Results Saffron demonstrated significant protection against selenite-induced cataractogenesis in vivo. The mean activities of superoxide dismutase, glutathione peroxidase, catalase, and glutathione levels were significantly increased in group III compared to the selenite-treated group. Saffron significantly prevented selenite-induced lipid peroxidation, protein oxidation, and proteolysis and insolubilization of the lens WSF. Conclusions Saffron extract prevented selenite-induced cataract formation in Wistar rats, possibly through the reinforcement of antioxidant status, reduction of the intensity of lipid peroxidation, protection of the sulfhydryl groups, and inhibition of proteolysis of the lens WSF. These findings highlight the anticataractogenic potential of saffron by virtue of its antioxidant property. PMID:23734088

Absence of acute ocular damage in humans after prolonged exposure to intense RF EMF

NASA Astrophysics Data System (ADS)

Adibzadeh, F.; van Rhoon, G. C.; Verduijn, G. M.; Naus-Postema, N. C.; Paulides, M. M.

2016-01-01

The eye is considered to be a critical organ when determining safety standards for radio frequency (RF) radiation. Experimental data obtained using animals showed that RF heating of the eye, particularly over a specific threshold, can induce cataracts. During the treatment of cancer in the head and neck by hyperthermia, the eyes receive a considerable dose of RF radiation due to stray radiation from the prolonged (60 min) and intense exposure at 434 MHz of this region. In the current study, we verified the exposure guidelines for humans by determining the association between the electromagnetic and thermal dose in the eyes with the reported ocular effects. We performed a simulation study to retrospectively assess the specific absorption rate (SAR) and temperature increase in the eyes of 16 selected patients (encompassing a total of 74 treatment sessions) whose treatment involved high power delivery as well as a minimal distance between the tumor site and the eye. Our results show that the basic restrictions on the peak 10 g spatial-averaged SAR (10 W kg-1) and peak tissue temperature increase (1 °C) are exceeded by up to 10.4 and 4.6 times, on average, and by at least 6.2 and 1.8 times when considering the lower limit of the 95% confidence interval. Evaluation of the acute effects according to patients’ feedback (all patients), the common toxicity criteria scores (all patients) and an ophthalmology investigation (one patient with the highest exposure) revealed no indication of any serious acute ocular effect, even though the eyes were exposed to high electromagnetic fields, leading to a high thermal dose. We also found that, although there is a strong correlation (R 2  =  0.88) between the predicted induced SAR and temperature in the eye, there are large uncertainties regarding the temperature-SAR relationship. Given this large uncertainty (129%) compared with the uncertainty of 3D temperature simulations (61%), we recommend using temperature simulations as a dosimetric measure in electromagnetic exposure risk assessments.

Cataract, Visual Impairment and Long-Term Mortality in a Rural Cohort in India: The Andhra Pradesh Eye Disease Study

PubMed Central

Khanna, Rohit C.; Murthy, Gudlavalleti V. S.; Giridhar, Pyda; Krishnaiah, Sannapaneni; Pant, Hira B.; Palamaner Subash Shantha, Ghanshyam; Chakrabarti, Subhabrata; Gilbert, Clare; Rao, Gullapalli N.

2013-01-01

Background A large-scale prevalence survey of blindness and visual impairment (The Andhra Pradesh Eye Diseases Study [APEDS1]) was conducted between 1996-2000 on 10,293 individuals of all ages in three rural and one urban clusters in Andhra Pradesh, Southern India. More than a decade later (June 2009-March 2010), APEDS1 participants in rural clusters were traced (termed APEDS2) to determine ocular risk factors for mortality in this longitudinal cohort. Methods and Findings Mortality hazard ratio (HR) analysis was performed for those aged >30 years at APEDS1, using Cox proportional hazard regression models to identify associations between ocular exposures and risk of mortality. Blindness and visual impairment (VI) were defined using Indian definitions. 799/4,188 (19.1%) participants had died and 308 (7.3%) had migrated. Mortality was higher in males than females (p<0.001). In multivariable analysis, after adjusting for age, gender, diabetes, hypertension, body mass index, smoking and education status the mortality HR was 1.9 (95% CI: 1.5-2.5) for blindness; 1.4 (95% CI: 1.2-1.7) for VI; 1.8 (95% CI: 1.4-2.3) for pure nuclear cataract, 1.5 (95% CI: 1.1-2.1) for pure cortical cataract; 1.96 (95% CI: 1.6-2.4) for mixed cataract, 2.0 (95% CI: 1.4-2.9) for history of cataract surgery, and 1.58 (95% CI: 1.3-1.9) for any cataract. When all these factors were included in the model, the HRs were attenuated, being 1.5 (95% CI: 1.1-2.0) for blindness and 1.2 (95% CI: 0.9-1.5) for VI. For lens type, the HRs were as follows: pure nuclear cataract, 1.6 (95% CI: 1.3-2.1); pure cortical cataract, 1.5 (95% CI: 1.1-2.1); mixed cataract, 1.8 (95% CI: 1.4-2.2), and history of previous cataract surgery, 1.8 (95% CI: 1.3-2.6). Conclusions All types of cataract, history of cataract surgery and VI had an increased risk of mortality that further suggests that these could be potential markers of ageing. PMID:24282482

Cataract surgery cost utility revisited in 2012: a new economic paradigm.

PubMed

Brown, Gary C; Brown, Melissa M; Menezes, Alicia; Busbee, Brandon G; Lieske, Heidi B; Lieske, Philip A

2013-12-01

To assess the 2012 cost utility of cataract surgery in the United States and to compare 2012 cost-utility data with those from 2000. Value-Based Medicine (Flourtown, PA), patient preference-based, comparative effectiveness analysis and cost-utility analysis using 2012 real United States dollars. Previously published Patient Outcomes Research Team Study data and time tradeoff utilities obtained from patients with vision loss. Visual acuity measurements from patients wtih untreated cataract were used as controls. Thirteen-year, average, first-eye and second-eye cataract surgery cost-utility analysis using the societal and third-party insurer cost perspectives. Patient value gain in quality-adjusted life years (QALYs) and percent gain in quality of life as well as the cost-utility ratio using the dollars expended per QALY gained. Patient and financial value outcomes were discounted at 3% annually with net present value analysis. First-eye cataract surgery conferred 1.6212 QALYs over the 13-year model, a 20.8% quality-of-life gain. Bilateral cataract surgery conferred 2.8152 QALYs over 13 years, a 36.2% improvement in quality of life. The direct ophthalmic medical cost for unilateral cataract surgery in 2012 United States nominal dollars was $2653, an inflation-adjusted 34.2% less than in 2000 and 85% less than in 1985. The 2012 inflation-adjusted physician fee was 10.1% of that in 1985. The 13-year societal cost perspective, financial return on investment (ROI) for first-eye cataract surgery was $121,198, a 4567% gain. The third-party insurer cost perspective average cost-utility ratio was $2653/1.6212 = $1636/QALY for unilateral cataract surgery, whereas the societal cost perspective average cost-utility ratio was -$121,198/1.6212 = -$74,759/QALY. The net 13-year $123.4-billion financial ROI from a 1-year cohort of cataract surgery patients was accrued: Medicare, $36.4 billion; Medicaid, $3.3 billion; other insurers, $9.6 billion; patients, $48.6 billion; and increased United States national productivity, $25.4 billion. Cataract surgery in 2012 greatly improved quality of life and was highly cost effective. It was 34.4% less expensive than in 2000 and 85% less expensive than in 1985. Initial cataract surgery yielded an extraordinary 4567% financial ROI to society over the 13-year model. Copyright © 2013 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Epidemiologic study of age-related cataracts among an elderly Chinese population in Shih-Pai, Taiwan.

PubMed

Tsai, Su-Ying; Hsu, Wen-Ming; Cheng, Ching-Yu; Liu, Jorn-Hon; Chou, Pesus

2003-06-01

The purpose of this study was to determine the prevalence and risk factors for age-related cataracts in a metropolitan elderly Chinese population in Shihpai, Taipei, Taiwan. Population-based cross-sectional study. A total of 2045 subjects at least 65 years of age were invited to participate, and 1361 (66.6%) participated in the survey. An eye examination, including lens opacity grading, was conducted by ophthalmologists using the Lens Opacity Classification System III (LOCS III). A structured questionnaire was used for data collection. Interviewers also collected information on subjects' blood pressure, lifestyle (cigarette smoking and alcohol intake), medical history, and waist and hip circumferences. Subjects were defined as having age-related cataracts if there was any type of lens opacity with an LOCS III grade of more than 2 in one or both eyes. When both eyes of an individual had age-related cataracts, the more affected eye was used for analysis. Among the 1361 participants, 806 were diagnosed with age-related cataracts. The prevalence was 59.2% (95% confidence interval, 56.6%-61.8%). Women had a higher prevalence of cataracts than men (64.0% vs. 56.1%, P = 0.004). The prevalence of age-related cataracts increased with age (P = 0.001). Nuclear opacity was the most prevalent type (38.9%), followed by cortical opacity (21.9%) and posterior subcapsular opacity (9.2%). On the basis of the final logistic regression model, after controlling for all other covariates, increased age and female gender were factors that were associated with an increased risk for all types of cataracts. Besides age and gender, the most significant risk factor for nuclear cataracts was current cigarette smoking; the significant predictors for cortical cataracts were higher systolic blood pressure, a history of cigarette smoking in the past, and history of diabetes; the significant predictor for posterior subcapsular cataracts was higher systolic blood pressure. The increasing prevalence of age-related cataracts with age highlights the need to seek appropriate medical services and for preventative interventions. Elderly people often ignore the importance of seeking vision services and care to prevent blindness or visual impairment. These findings suggest that the elderly need to be educated regarding the importance of eye care by physicians and hygiene authorities in Taiwan.

Advances in pharmacological strategies for the prevention of cataract development

PubMed Central

Gupta, S K; Selvan, V Kalai; Agrawal, S S; Saxena, Rohit

2009-01-01

Cataractous-opacification of the lens is one of the leading causes of blindness in India. The situation can be managed by surgical removal of the cataractous lens. Various pharmacological strategies have been proposed for the prevention and treatment of cataract. Information on possible benefits of putative anticataract agents comes from a variety of approaches, ranging from laboratory experiments, both in vitro and in vivo, to epidemiological studies in patients. This review deals with the various mechanisms, and possible pharmacological interventions for the prevention of cataract. The article also reviews research on potential anticataractous agents, including aldose reductase inhibitors, glutathione boosters, antiglycating agents, vitamins and various drugs from indigenous sources. PMID:19384010

Cataract Surgery Tool

NASA Technical Reports Server (NTRS)

1977-01-01

The NASA-McGannon cataract surgery tool is a tiny cutter-pump which liquefies and pumps the cataract lens material from the eye. Inserted through a small incision in the cornea, the tool can be used on the hardest cataract lens. The cutter is driven by a turbine which operates at about 200,000 revolutions per minute. Incorporated in the mechanism are two passages for saline solutions, one to maintain constant pressure within the eye, the other for removal of the fragmented lens material and fluids. Three years of effort have produced a design, now being clinically evaluated, with excellent potential for improved cataract surgery. The use of this tool is expected to reduce the patient's hospital stay and recovery period significantly.

Multi-resolution voxel phantom modeling: a high-resolution eye model for computational dosimetry

NASA Astrophysics Data System (ADS)

Caracappa, Peter F.; Rhodes, Ashley; Fiedler, Derek

2014-09-01

Voxel models of the human body are commonly used for simulating radiation dose with a Monte Carlo radiation transport code. Due to memory limitations, the voxel resolution of these computational phantoms is typically too large to accurately represent the dimensions of small features such as the eye. Recently reduced recommended dose limits to the lens of the eye, which is a radiosensitive tissue with a significant concern for cataract formation, has lent increased importance to understanding the dose to this tissue. A high-resolution eye model is constructed using physiological data for the dimensions of radiosensitive tissues, and combined with an existing set of whole-body models to form a multi-resolution voxel phantom, which is used with the MCNPX code to calculate radiation dose from various exposure types. This phantom provides an accurate representation of the radiation transport through the structures of the eye. Two alternate methods of including a high-resolution eye model within an existing whole-body model are developed. The accuracy and performance of each method is compared against existing computational phantoms.

Cataract formation associated with ocular toxocariasis.

PubMed

Ahn, Seong Joon; Woo, Se Joon; Hyon, Joon Young; Park, Kyu Hyung

2013-06-01

To report the clinical features of cataracts in eyes with ocular toxocariasis. Department of Ophthalmology, Seoul National University Bundang Hosptal, Seongnam, South Korea. Retrospective observational case series. The clinical diagnosis of ocular toxocariasis was based on the following characteristic features: retinal granuloma with or without ocular inflammation and positive results in serum antibody enzyme-linked immunosorbent assay. Patients younger than 60 years who presented with a unilateral cataract and were diagnosed with ocular toxocariasis between January 2009 and January 2012 were included. Demographic and ocular examination data for all patients showing atypical cataract features were collected. All cataracts were documented with anterior segment photography. Seven of 83 patients (8.4%) presented with an atypical cataract in the eye with ocular toxocariasis only. The mean patient age was 49.7 years ± 8.3 (SD) (range 38 to 59 years). All patients had small, round, white lens opacities resembling retinal granulomas. The granuloma-like opacities were located primarily in the lens midperiphery and in the subcapsular level. The lens opacity migrated in 1 patient. Ocular toxocariasis can cause a cataract with distinctive clinical features. These cataracts show a granuloma-like opacity primarily in the posterior subcapsular level; the opacity can migrate. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2013 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Non-syndromic posterior lenticonus a cause of childhood cataract: evidence for X-linked inheritance.

PubMed

Russell-Eggitt, I M

2000-12-01

When an X-linked pedigree of posterior lenticonus with cataract was identified further evidence for X-linked inheritance of this condition was sought. Forty-three cases of posterior lenticonus were identified from a database of 354 children with cataract. Two children with the X-linked syndromes of Lowe and Nance-Horan and 3 children with Fanconi syndrome have been excluded from further analysis. None of the children was deaf. None of the non-syndromic cases had microcornea. There were 38 cases of non-syndromic posterior lenticonus (approximately 11%). There were 15 children from 13 pedigrees and 23 apparently sporadic cases. Of the 106 cases on the database with unilateral cataract 15 had posterior lenticonus (approximately 14%). Eleven of 13 pedigrees were compatible with X-linked inheritance or autosomal dominant inheritance with variable expression. However, in 2 pedigrees there was father to son transmission. Posterior lenticonus is a common cause of unilateral infantile cataract, but is thought to be a rare cause of bilateral cataracts. This study suggests that posterior lenticonus is responsible for a significant proportion of childhood cataracts (approximately 14% of unilateral and approximately 9% of bilateral cases). Posterior lenticonus is generally thought to occur as a sporadic condition. This study demonstrates that there is a family history of early-onset cataract in a significant number of bilateral cases (approximately 58%).