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Sample records for exhibit decreased intraocular

  1. Thermoelectric device exhibiting decreased stress

    SciTech Connect

    Heath, D.L.; Chou, D.J.

    1985-02-05

    A thermoelectric device exhibiting both structural integrity and decreased stress across the device notwithstanding the application of thermally cycled temperature differentials thereacross includes, electrically interconnected thermoelectric elements and a rigidly affixed substrate. Thermal stress is relieved by using flexible conductors to interconnect the thermoelectric elements, and by the use of a flexile joint to attach a second substrate to the remainder of the device. Complete elimination of the second substrate may also be used to eliminate stress. Presence of the rigidly affixed substrate gives the device sufficient structural integrity to enable it to withstand rugged conditions.

  2. Argon laser trabeculoplasty as a means of decreasing intraocular pressure from ''normal'' levels in glaucomatous eyes

    SciTech Connect

    Sharpe, E.D.; Simmons, R.J.

    1985-06-15

    The authors conducted a retrospective study of 67 patients (85 eyes) with severe glaucoma to determine whether argon laser trabeculoplasty could reduce intraocular pressures below the ''normal'' range. All patients had initial intraocular pressures of less than or equal to 19 mm Hg. Success was defined as a decrease in intraocular pressure of at least 20%, no increase in medications, stable visual field, and no subsequent glaucoma surgery. After an average follow-up period of 30 months, treatment was successful in 31 cases. One half of the failures occurred by six months and 11 failures (30%) occurred after 12 months. Sixteen patients were able to decrease their medications. Two patients achieved intraocular pressures between 6 and 9 mm Hg and 20 between 10 and 12 mm Hg.

  3. Elevated intraocular pressure decreases response sensitivity of inner retinal neurons in experimental glaucoma mice

    PubMed Central

    Pang, Ji-Jie; Frankfort, Benjamin J.; Gross, Ronald L.; Wu, Samuel M.

    2015-01-01

    Glaucoma is the second leading cause of blindness in the United States and the world, characterized by progressive degeneration of the optic nerve and retinal ganglion cells (RGCs). Glaucoma patients exhibit an early diffuse loss of retinal sensitivity followed by focal loss of RGCs in sectored patterns. Recent evidence has suggested that this early sensitivity loss may be associated with dysfunctions in the inner retina, but detailed cellular and synaptic mechanisms underlying such sensitivity changes are largely unknown. In this study, we use whole-cell voltage-clamp techniques to analyze light responses of individual bipolar cells (BCs), AII amacrine cells (AIIACs), and ON and sustained OFF alpha-ganglion cells (ONαGCs and sOFFαGCs) in dark-adapted mouse retinas with elevated intraocular pressure (IOP). We present evidence showing that elevated IOP suppresses the rod ON BC inputs to AIIACs, resulting in less sensitive AIIACs, which alter AIIAC inputs to ONαGCs via the AIIAC→cone ON BC→ONαGC pathway, resulting in lower ONαGC sensitivity. The altered AIIAC response also reduces sOFFαGC sensitivity via the AIIAC→sOFFαGC chemical synapses. These sensitivity decreases in αGCs and AIIACs were found in mice with elevated IOP for 3–7 wk, a stage when little RGC or optic nerve degeneration was observed. Our finding that elevated IOP alters neuronal function in the inner retina before irreversible structural damage occurs provides useful information for developing new diagnostic tools and treatments for glaucoma in human patients. PMID:25675503

  4. Pregnenolone sulfate decreases intraocular pressure and changes expression of sigma receptor in a model of chronic ocular hypertension.

    PubMed

    Sun, Xian; Cheng, Fang; Meng, Bo; Yang, Binbin; Song, Wulian; Yuan, Huiping

    2012-06-01

    Sigma receptors are Ca(2+)-sensitive, ligand-operated receptor chaperones at the mitochondrion-associated endoplasmic reticulum membrane. This study describes the effect of the sigma receptor 1 agonist pregnenolone sulfate on intraocular pressure (IOP) and sigma receptor 1 expression in rat retinas after chronic ocular hypertension. Chronic ocular hypertension was induced by occlusion of episcleral veins. Retinal histological sections were obtained to determine inner plexiform layer thickness and the number of cell bodies in the ganglion cell layer. Sigma receptor expression in rat retinas was analyzed by RT-PCR and Western blotting. Cauterization caused IOP to increase >73%, and the pressure was maintained for 2 months. A time-dependent loss of ganglion cells and retinal thickness occurred at elevated IOP. High IOP decreased sigma receptor 1 expression during the first week, but expression was increased at 8 weeks. Injected pregnenolone significantly decreased IOP, prevented ganglion cell loss, protected inner plexiform layer thickness, and increased sigma receptor 1 expression in episcleral vein-cauterized rats. Sigma receptors appear to be neuroprotective and potential targets for glaucoma therapeutics.

  5. Atracurium and intraocular pressure.

    PubMed Central

    Murphy, D F; Eustace, P; Unwin, A; Magner, J B

    1985-01-01

    The effect of atracurium on intraocular pressure was studied by comparing it with pancuronium in a randomised controlled trial. The intraocular pressure was measured in patients undergoing cataract surgery before administration of the muscle relaxant, at 1, 3, and 5 minutes after its administration, and at 1 minute after tracheal intubation. Atracurium was found to decrease intraocular pressure to a significantly greater degree than pancuronium. The intraocular pressure after tracheal intubation was found to be significantly higher than that measured immediately after induction of anaesthesia. The authors conclude that atracurium provides an acceptable alternative to pancuronium for ophthalmic surgery but does not overcome the ocular hypertensive effect of tracheal intubation. PMID:3899166

  6. Laminin α4 Deficient Mice Exhibit Decreased Capacity for Adipose Tissue Expansion and Weight Gain

    PubMed Central

    Movérare-Skrtic, Sofia; Kortesmaa, Jarkko; Soininen, Raija; Bergström, Göran; Ohlsson, Claes; Chong, Li Yen; Rozell, Björn; Emont, Margo; Cohen, Ronald N.; Brey, Eric M.; Tryggvason, Karl

    2014-01-01

    Obesity is a global epidemic that contributes to the increasing medical burdens related to type 2 diabetes, cardiovascular disease and cancer. A better understanding of the mechanisms regulating adipose tissue expansion could lead to therapeutics that eliminate or reduce obesity-associated morbidity and mortality. The extracellular matrix (ECM) has been shown to regulate the development and function of numerous tissues and organs. However, there is little understanding of its function in adipose tissue. In this manuscript we describe the role of laminin α4, a specialized ECM protein surrounding adipocytes, on weight gain and adipose tissue function. Adipose tissue accumulation, lipogenesis, and structure were examined in mice with a null mutation of the laminin α4 gene (Lama4−/−) and compared to wild-type (Lama4+/+) control animals. Lama4−/− mice exhibited reduced weight gain in response to both age and high fat diet. Interestingly, the mice had decreased adipose tissue mass and altered lipogenesis in a depot-specific manner. In particular, epididymal adipose tissue mass was specifically decreased in knock-out mice, and there was also a defect in lipogenesis in this depot as well. In contrast, no such differences were observed in subcutaneous adipose tissue at 14 weeks. The results suggest that laminin α4 influences adipose tissue structure and function in a depot-specific manner. Alterations in laminin composition offers insight into the roll the ECM potentially plays in modulating cellular behavior in adipose tissue expansion. PMID:25310607

  7. Intraocular cyclophotocoagulation.

    PubMed

    Shields, M B

    1986-01-01

    Laser energy, as a cyclodestructive source for the treatment of glaucoma, can be delivered by several routes. The transscleral approach has the advantages of being noninvasive and relatively quick and easy, but the disadvantages of unpredictable results and a high complication rate. Transpupillary cyclophotocoagulation has fewer complications, but is only possible in a small number of eyes. The intraocular intraocular route is a newer technique, which utilises endophotocoagulation through a pars plana incision to treat ciliary processes in aphakic eyes. Visualisation for intraocular cyclophotocoagulation can be either transpupillary with scleral depression to expose the processes or by the use of an endoscope.

  8. Decreased visual acuity resulting from glistening and sub-surface nano-glistening formation in intraocular lenses: A retrospective analysis of 5 cases

    PubMed Central

    Matsushima, Hiroyuki; Nagata, Mayumi; Katsuki, Yoko; Ota, Ichiro; Miyake, Kensaku; Beiko, George H.H.; Grzybowski, Andrzej

    2015-01-01

    Background To report on five patients with decreased visual acuity due to glistening and severe sub-surface nano-glistening (SSNG) formation within their intraocular lenses (IOLs). Design Case reports and analysis of extracted IOLs. Participants and samples We report improved visual acuity when IOLs with severe glistening and SSNG were exchanged for clear IOLs in five patients. Methods Case reports. Main outcome measures The main outcome measure was visual acuity. The secondary outcome measure was light transmission. Explanted IOLs were subjected to investigation. Pre- and postoperative slit lamp images of the anterior eye and microscopic images of the extracted IOLs were taken and compared. Light transmission of the IOL was measured using a double beam type spectrophotometer. An integrated value of the percentage light transmittance in the visible light spectrum was calculated. Results We report on five patients whose visual acuity improved when IOLs were exchanged because of severe glistening and SSNG. All of the affected IOLs were MA60BM (Alcon, Forth Wroth Texas, USA) and the original implantation had occurred over a range of 6–15 years prior to the IOL exchange. Light transmission was decreased in all affected lenses compared to a similar control IOL. Conclusions Although only a few reports of cases in which glistening and SSNG have progressed to the level of decreased visual function have been published, the likelihood is that this phenomena will increase as the severity and incidence of these inclusions have been shown to increase with time. Appropriate evaluations of visual function in such patients are needed and consideration should be given to IOL exchange in symptomatic patients. PMID:26586975

  9. Primary Intraocular Lymphoma

    PubMed Central

    Faia, Lisa J.; Chan, Chi-Chao

    2009-01-01

    Primary intraocular lymphoma, recently suggested to be renamed primary retinal lymphoma, is a subset of primary central nervous system lymphoma and is usually an aggressive diffuse large B-cell lymphoma. Between 56% and 85% of patients who initially present with primary intraocular lymphoma alone will develop cerebral lesions. Patients typically complain of decreased vision and floaters, most likely secondary to the chronic vitritis and subretinal lesions. The diagnosis of primary intraocular lymphoma can be difficult to make and requires tissue for diagnosis. The atypical lymphoid cells are large and display a high nuclear to cytoplasmic ratio, prominent nucleoli, and basophilic cytoplasm. Flow cytometry, immunohistochemistry, cytokine analysis, and gene rearrangements also aid in the diagnosis. Local and systemic treatments, such as chemotherapy and radiation, are employed, although the relapse rate remains high. PMID:19653715

  10. Severe South American Ocular Toxoplasmosis Is Associated with Decreased Ifn-γ/Il-17a and Increased Il-6/Il-13 Intraocular Levels

    PubMed Central

    de-la-Torre, Alejandra; Sauer, Arnaud; Pfaff, Alexander W.; Bourcier, Tristan; Brunet, Julie; Speeg-Schatz, Claude; Ballonzoli, Laurent; Villard, Odile; Ajzenberg, Daniel; Sundar, Natarajan; Grigg, Michael E.

    2013-01-01

    In a cross sectional study, 19 French and 23 Colombian cases of confirmed active ocular toxoplasmosis (OT) were evaluated. The objective was to compare clinical, parasitological and immunological responses and relate them to the infecting strains. A complete ocular examination was performed in each patient. The infecting strain was characterized by genotyping when intraocular Toxoplasma DNA was detectable, as well as by peptide-specific serotyping for each patient. To characterize the immune response, we assessed Toxoplasma protein recognition patterns by intraocular antibodies and the intraocular profile of cytokines, chemokines and growth factors. Significant differences were found for size of active lesions, unilateral macular involvement, unilateral visual impairment, vitreous inflammation, synechiae, and vasculitis, with higher values observed throughout for Colombian patients. Multilocus PCR-DNA sequence genotyping was only successful in three Colombian patients revealing one type I and two atypical strains. The Colombian OT patients possessed heterogeneous atypical serotypes whereas the French were uniformly reactive to type II strain peptides. The protein patterns recognized by intraocular antibodies and the cytokine patterns were strikingly different between the two populations. Intraocular IFN-γ and IL-17 expression was lower, while higher levels of IL-13 and IL-6 were detected in aqueous humor of Colombian patients. Our results are consistent with the hypothesis that South American strains may cause more severe OT due to an inhibition of the protective effect of IFN-γ. PMID:24278490

  11. Whole-Genome Sequences of Burkholderia pseudomallei Isolates Exhibiting Decreased Meropenem Susceptibility.

    PubMed

    Price, Erin P; Smith, Melissa Laird; Paxinos, Ellen E; Tallon, Luke J; Sadzewicz, Lisa; Sengamalay, Naomi; Baird, Robert W; Currie, Bart J; Sarovich, Derek S

    2017-04-06

    We report here paired isogenic Burkholderia pseudomallei genomes obtained from three patients receiving intravenous meropenem for melioidosis treatment, with post-meropenem isolates developing decreased susceptibility. Two genomes were finished, and four were drafted to improved high-quality standard. These genomes will be used to identify meropenem resistance mechanisms in B. pseudomallei.

  12. Whole-Genome Sequences of Burkholderia pseudomallei Isolates Exhibiting Decreased Meropenem Susceptibility

    PubMed Central

    Smith, Melissa Laird; Paxinos, Ellen E.; Tallon, Luke J.; Sadzewicz, Lisa; Sengamalay, Naomi; Baird, Robert W.; Currie, Bart J.

    2017-01-01

    ABSTRACT We report here paired isogenic Burkholderia pseudomallei genomes obtained from three patients receiving intravenous meropenem for melioidosis treatment, with post-meropenem isolates developing decreased susceptibility. Two genomes were finished, and four were drafted to improved high-quality standard. These genomes will be used to identify meropenem resistance mechanisms in B. pseudomallei. PMID:28385830

  13. Ascorbate-Deficient vtc2 Mutants in Arabidopsis Do Not Exhibit Decreased Growth.

    PubMed

    Lim, Benson; Smirnoff, Nicholas; Cobbett, Christopher S; Golz, John F

    2016-01-01

    In higher plants the L-galactose pathway represents the major route for ascorbate biosynthesis. The first committed step of this pathway is catalyzed by the enzyme GDP-L-galactose phosphorylase and is encoded by two paralogs in Arabidopsis - VITAMIN C2 (VTC2) and VTC5. The first mutant of this enzyme, vtc2-1, isolated via an EMS mutagenesis screen, has approximately 20-30% of wildtype ascorbate levels and has been reported to have decreased growth under standard laboratory conditions. Here, we show that a T-DNA insertion into the VTC2 causes a similar reduction in ascorbate levels, but does not greatly affect plant growth. Subsequent segregation analysis revealed the growth defects of vtc2-1 mutants segregate independently of the vtc2-1 mutation. These observations suggest that it is the presence of an independent cryptic mutation that affects growth of vtc2-1 mutants, and not the 70-80% decrease in ascorbate levels that has been assumed in past studies.

  14. Autistic Children Exhibit Decreased Levels of Essential Fatty Acids in Red Blood Cells

    PubMed Central

    Brigandi, Sarah A.; Shao, Hong; Qian, Steven Y.; Shen, Yiping; Wu, Bai-Lin; Kang, Jing X.

    2015-01-01

    Omega-6 (n-6) and omega-3 (n-3) polyunsaturated fatty acids (PUFA) are essential nutrients for brain development and function. However, whether or not the levels of these fatty acids are altered in individuals with autism remains debatable. In this study, we compared the fatty acid contents between 121 autistic patients and 110 non-autistic, non-developmentally delayed controls, aged 3–17. Analysis of the fatty acid composition of red blood cell (RBC) membrane phospholipids showed that the percentage of total PUFA was lower in autistic patients than in controls; levels of n-6 arachidonic acid (AA) and n-3 docosahexaenoic acid (DHA) were particularly decreased (p < 0.001). In addition, plasma levels of the pro-inflammatory AA metabolite prostaglandin E2 (PGE2) were higher in a subset of the autistic participants (n = 20) compared to controls. Our study demonstrates an alteration in the PUFA profile and increased production of a PUFA-derived metabolite in autistic patients, supporting the hypothesis that abnormal lipid metabolism is implicated in autism. PMID:25946342

  15. Phakic Intraocular Lenses

    MedlinePlus

    ... Implants and Prosthetics Phakic Intraocular Lenses Phakic Intraocular Lenses Share Tweet Linkedin Pin it More sharing options Linkedin Pin it Email Print Phakic intraocular lenses are new devices used to correct nearsightedness. These ...

  16. Intraocular magnet of Parel.

    PubMed Central

    Crock, G. W.; Janakiraman, P.; Reddy, P.

    1986-01-01

    The intraocular magnet (IOM) is a new device based on permanent magnetism providing controlled energy for removal of magnetic intraocular foreign bodies. Its use is reported in 11 cases. Images PMID:3801364

  17. Bilateral intraocular pressure elevation and decrease of facility of aqueous humour outflow as a consequence of regional lymphoedema of head and neck.

    PubMed

    Holló, G

    1993-06-01

    Aqueous humour drainage to the deep cervical lymphatics has been proven in animal experiments, but there have been no observations of changes in intraocular pressure (IOP) or aqueous humour drainage as a consequence of lymph drainage dysfunction. The history of a patient with non-Hodgkin's lymphoma, who underwent a left-sided radical neck dissection in January 1991, is reported. From the end of 1991 lymphoedema of the head and neck, predominantly on the right side, developed without venous stasis but with significant bilateral IOP elevation and aqueous humour outflow reduction, refract to conventional treatment. Two days after cytostatic treatment the lymphoedema disappeared, and IOP and aqueous humour outflow became normal. Four days later the patient died because of an acute bronchopneumonia. The pathological examination revealed an intact internal jugular venous system, enlarged lymph nodes and, as a consequence of previous irradiation, cicatrization in the right side of the neck. On the left side, there was absence of the internal jugular vein and jugular lymphatic trunk due to previous radical neck dissection. Our case suggests that regional lymphatic stasis and the absence of the collateral drainage to the contralateral side significantly reduces the aqueous humour outflow and leads to a bilateral, secondary IOP elevation.

  18. Mice with neuropathic pain exhibit morphine tolerance due to a decrease in the morphine concentration in the brain.

    PubMed

    Ochiai, Wataru; Kaneta, Mitsumasa; Nagae, Marina; Yuzuhara, Ami; Li, Xin; Suzuki, Haruka; Hanagata, Mika; Kitaoka, Satoshi; Suto, Wataru; Kusunoki, Yoshiki; Kon, Risako; Miyashita, Kazuhiko; Masukawa, Daiki; Ikarashi, Nobutomo; Narita, Minoru; Suzuki, Tsutomu; Sugiyama, Kiyoshi

    2016-09-20

    The chronic administration of morphine to patients with neuropathic pain results in the development of a gradual tolerance to morphine. Although the detailed mechanism of this effect has not yet been elucidated, one of the known causes is a decrease in μ-opioid receptor function with regard to the active metabolite of morphine, M-6-G(morphine-6-glucuronide), in the ventrotegmental area of the midbrain. In this study, the relationship between the concentration of morphine in the brain and its analgesic effect was examined after the administration of morphine in the presence of neuropathic pain. Morphine was orally administered to mice with neuropathic pain, and the relationship between morphine's analgesic effect and its concentration in the brain was analysed. In addition, the expression levels of the conjugation enzyme, UGT2B (uridine diphosphate glucuronosyltransferase), which has morphine as its substrate, and P-gp, which is a transporter involved in morphine excretion, were examined. In mice with neuropathic pain, the concentration of morphine in the brain was significantly decreased, and a correlation was found between this decrease and the decrease in the analgesic effect. It was considered possible that this decrease in the brain morphine concentration may be due to an increase in the expression level of P-gp in the small intestine and to an increase in the expression level and binding activity of UGT2B in the liver. The results of this study suggest the possibility that a sufficient analgesic effect may not be obtained when morphine is administered in the presence of neuropathic pain due to a decrease in the total amount of morphine and M-6-G that reach the brain.

  19. Cattle with increased severity of bovine respiratory disease complex exhibit decreased capacity to protect against histone cytotoxicity.

    PubMed

    Matera, J A; Wilson, B K; Hernandez Gifford, J A; Step, D L; Krehbiel, C R; Gifford, C A

    2015-04-01

    Bovine respiratory disease complex (BRDC) is the leading cause of morbidity and mortality in feedlot cattle. Significant inflammation and lesions are often observed in lungs of infected cattle. During acute inflammatory responses, histones contribute to mortality in rodents and humans and serum proteins can protect against histone-induced cytotoxicity. We hypothesized that cattle experiencing chronic or fatal cases of BRDC have reduced ability to protect against cytotoxic effects of histones. Serum samples were collected from 66 bull calves at the time of normal feedlot processing procedures. Animals were retrospectively assigned to groups consisting of calves never treated for BRDC (control [CONT]; n = 10), calves treated with antimicrobials once for BRDC (1T; n = 16), calves treated twice for BRDC (2T; n = 13), calves treated 3 times for BRDC (3T; n = 14), or calves treated 4 times for BRDC (4T; n = 13). Samples were also collected each time animals received antimicrobial treatment; animals within a group were further sorted by calves that recovered and calves that died to test histone cytotoxicity. Bovine kidney cells were cultured in duplicate in 96-well plates and exposed to 0 or 50 μg/mL of total histones for 18 h with 1% serum from each animal. Cell viability was assessed by the addition of resazurin for 6 h followed by fluorescent quantification. Fluorescent values from serum alone were subtracted from values obtained for histone treatment for each animal. Serum from CONT, 1T, and 2T at initial processing all exhibited a similar (P > 0.10) response to histone treatment with fluorescent values of -312 ± 557, -1,059 ± 441, and -975 ± 489, respectively. However, 3T and 4T demonstrated an impaired capacity (P < 0.05) to protect against histones (-2,778 ± 471 and -3,026 ± 489) at initial processing when compared to the other groups. When sorted by mortality within group, calves that were treated twice and recovered (-847 ± 331) demonstrated a greater (P

  20. Effects of Different Intensities of Exercise on Intraocular Pressure

    ERIC Educational Resources Information Center

    Rowe, Deryl; And Others

    1976-01-01

    The decrease in intraocular pressure during exercise and the first few minutes of recovery is related to a decrease in blood pH and an increase in blood lactate concentration, not to the intensity of the exercise. (MB)

  1. Pseudophakia and intraocular pressure.

    PubMed

    Radius, R L; Schultz, K; Sobocinski, K; Schultz, R O; Easom, H

    1984-06-01

    We studied the change in intraocular pressure in 373 consecutive eyes undergoing cataract extraction with intraocular lens implantation between Jan. 1, 1981, and May 31, 1982. There was a mean increase in intraocular pressure of 0.1 mm Hg following this surgery. This increase, however, was not statistically significant (P greater than .5). There was a mean rise in pressure of 0.8 mm Hg in the eyes undergoing intracapsular surgery and a mean fall in pressure of 0.6 mm Hg in the eyes undergoing extracapsular surgery (P less than .05). The change in pressure was unrelated to age, surgeon, or lens type. The results of a separate analysis of 16 eyes with a preoperative diagnosis of glaucoma and eight eyes with ocular hypertension were similar.

  2. Former Abusers of Anabolic Androgenic Steroids Exhibit Decreased Testosterone Levels and Hypogonadal Symptoms Years after Cessation: A Case-Control Study

    PubMed Central

    Selmer, Christian; Østergren, Peter Busch; Pedersen, Karen Boje; Schou, Morten; Gustafsson, Finn; Faber, Jens; Juul, Anders; Kistorp, Caroline

    2016-01-01

    Aims Abuse of anabolic androgenic steroids (AAS) is highly prevalent among male recreational athletes. The objective of this study was to investigate the impact of AAS abuse on reproductive hormone levels and symptoms suggestive of hypogonadism in current and former AAS abusers. Methods This study had a cross-sectional case-control design and involved 37 current AAS abusers, 33 former AAS abusers (mean (95%CI) elapsed duration since AAS cessation: 2.5 (1.7; 3.7) years) and 30 healthy control participants. All participants were aged 18–50 years and were involved in recreational strength training. Reproductive hormones (FSH, LH, testosterone, inhibin B and anti-Müllerian hormone (AMH)) were measured using morning blood samples. Symptoms of hypogonadism (depressive symptoms, fatigue, decreased libido and erectile dysfunction) were recorded systematically. Results Former AAS abusers exhibited significantly lower median (25th –75th percentiles) total and free testosterone levels than control participants (total testosterone: 14.4 (11.9–17.7) nmol/l vs. 18.8 (16.6–22.0) nmol/l) (P < 0.01). Overall, 27.2% (13.3; 45.5) of former AAS abusers exhibited plasma total testosterone levels below the lower reference limit (12.1 nmol/l) whereas no control participants exhibited testosterone below this limit (P < 0.01). Gonadotropins were significantly suppressed, and inhibin B and AMH were significantly decreased in current AAS abusers compared with former AAS abusers and control participants (P < 0.01). The group of former AAS abusers had higher proportions of participants with depressive symptoms ((24.2%) (11.1; 42.2)), erectile dysfunction ((27.3%) (13.3; 45.6)) and decreased libido ((40.1%) (23.2; 57.0)) than the other two groups (trend analyses: P < 0.05). Conclusions Former AAS abusers exhibited significantly lower plasma testosterone levels and higher frequencies of symptoms suggestive of hypogonadism than healthy control participants years after AAS cessation

  3. Intraocular radiation blocking

    SciTech Connect

    Finger, P.T.; Ho, T.K.; Fastenberg, D.M.; Hyman, R.A.; Stroh, E.M.; Packer, S.; Perry, H.D. )

    1990-09-01

    Iodine-based liquid radiographic contrast agents were placed in normal and tumor-bearing (Greene strain) rabbit eyes to evaluate their ability to block iodine-125 radiation. This experiment required the procedures of tumor implantation, vitrectomy, air-fluid exchange, and 125I plaque and thermoluminescent dosimetry (TLD) chip implantation. The authors quantified the amount of radiation attenuation provided by intraocularly placed contrast agents with in vivo dosimetry. After intraocular insertion of a blocking agent or sham blocker (saline) insertion, episcleral 125I plaques were placed across the eye from episcleral TLD dosimeters. This showed that radiation attenuation occurred after blocker insertion compared with the saline controls. Then computed tomographic imaging techniques were used to describe the relatively rapid transit time of the aqueous-based iohexol compared with the slow transit time of the oil-like iophendylate. Lastly, seven nontumor-bearing eyes were primarily examined for blocking agent-related ocular toxicity. Although it was noted that iophendylate induced intraocular inflammation and retinal degeneration, all iohexol-treated eyes were similar to the control eyes at 7 and 31 days of follow-up. Although our study suggests that intraocular radiopaque materials can be used to shield normal ocular structures during 125I plaque irradiation, a mechanism to keep these materials from exiting the eye must be devised before clinical application.

  4. Effects of angiotensin, vasopressin and atrial natriuretic peptide on intraocular pressure in anesthetized rats

    NASA Technical Reports Server (NTRS)

    Palm, D. E.; Shue, S. G.; Keil, L. C.; Balaban, C. D.; Severs, W. B.

    1995-01-01

    The effects of atrial natriuretic peptide (ANP), vasopressin (AVP) and angiotensin (ANG) on blood and intraocular pressures of pentobarbital anesthetized rats were evaluated following intravenous, intracerebroventricular or anterior chamber routes of administration. Central injections did not affect intraocular pressure. Equipressor intravenous infusions of ANG raised, whereas AVP decreased, intraocular pressure. Direct infusions of a balanced salt solution (0.175 microliter/min) raised intraocular pressure between 30 and 60 min. Adding ANG or ANP slightly reduced this solvent effect but AVP was markedly inhibitory. An AVP-V1 receptor antagonist reversed the blunting of the solvent-induced rise by the peptide, indicating receptor specificity. Acetazolamide pretreatment lowered intraocular pressure, but the solvent-induced rise in intraocular pressure and inhibition by AVP still occurred without altering the temporal pattern. Thus, these effects appear unrelated to aqueous humor synthesis rate. The data support the possibility of intraocular pressure regulation by peptides acting from the blood and aqueous humor.

  5. Arabidopsis serotonin N-acetyltransferase knockout mutant plants exhibit decreased melatonin and salicylic acid levels resulting in susceptibility to an avirulent pathogen.

    PubMed

    Lee, Hyoung Yool; Byeon, Yeong; Tan, Dun-Xian; Reiter, Russel J; Back, Kyoungwhan

    2015-04-01

    Serotonin N-acetyltransferase (SNAT) is the penultimate enzyme in the melatonin biosynthesis pathway in plants. We examined the effects of SNAT gene inactivation in two Arabidopsis T-DNA insertion mutant lines. After inoculation with the avirulent pathogen Pseudomonas syringe pv. tomato DC3000 harboring the elicitor avrRpt2 (Pst-avrRpt2), melatonin levels in the snat knockout mutant lines were 50% less than in wild-type Arabidopsis Col-0 plants. The snat knockout mutant lines exhibited susceptibility to pathogen infection that coincided with decreased induction of defense genes including PR1, ICS1, and PDF1.2. Because melatonin acts upstream of salicylic acid (SA) synthesis, the reduced melatonin levels in the snat mutant lines led to decreased SA levels compared to wild-type, suggesting that the increased pathogen susceptibility of the snat mutant lines could be attributed to decreased SA levels and subsequent attenuation of defense gene induction. Exogenous melatonin treatment failed to induce defense gene expression in nahG Arabidopsis plants, but restored the induction of defense gene expression in the snat mutant lines. In addition, melatonin caused translocation of NPR1 (nonexpressor of PR1) protein from the cytoplasm into the nucleus indicating that melatonin-elicited pathogen resistance in response to avirulent pathogen attack is SA-dependent in Arabidopsis.

  6. Intraocular lens fabrication

    DOEpatents

    Salazar, Mike A.; Foreman, Larry R.

    1997-01-01

    This invention describes a method for fabricating an intraocular lens made rom clear Teflon.TM., Mylar.TM., or other thermoplastic material having a thickness of about 0.025 millimeters. These plastic materials are thermoformable and biocompatable with the human eye. The two shaped lenses are bonded together with a variety of procedures which may include thermosetting and solvent based adhesives, laser and impulse welding, and ultrasonic bonding. The fill tube, which is used to inject a refractive filling material is formed with the lens so as not to damage the lens shape. A hypodermic tube may be included inside the fill tube.

  7. Intraocular lens fabrication

    DOEpatents

    Salazar, M.A.; Foreman, L.R.

    1997-07-08

    This invention describes a method for fabricating an intraocular lens made from clear Teflon{trademark}, Mylar{trademark}, or other thermoplastic material having a thickness of about 0.025 millimeters. These plastic materials are thermoformable and biocompatable with the human eye. The two shaped lenses are bonded together with a variety of procedures which may include thermosetting and solvent based adhesives, laser and impulse welding, and ultrasonic bonding. The fill tube, which is used to inject a refractive filling material is formed with the lens so as not to damage the lens shape. A hypodermic tube may be included inside the fill tube. 13 figs.

  8. Laser therapy in intraocular tumors

    NASA Astrophysics Data System (ADS)

    Carstocea, Benone D.; Gafencu, Otilia L.; Apostol, Silvia

    1995-01-01

    Intraocular tumors present special problems of diagnosis and treatment. Diagnostic methods include, in addition to systemic and ophthalmological examinations, ancillary examinations such as transillumination, fluorescein angiography, ultrasonography, radioactive phosphorus uptake test, radiology, computerized tomography, and fine-needle aspiration biopsy with cytological analyses. Previously, enucleation of the involved eye was generally accepted as management of malignant tumors. Improved therapeutic methods such as photocoagulation and better surgical techniques now provide a variety of therapeutical alternatives. This study consists of 21 cases of intraocular tumors that were managed by Argon laser photocoagulation. Four cases were intraocular metastasis and 17 cases were primitive intraocular tumors. Argon laser therapy proved to be totally ineffective for the intraocular metastasis and a very adequate therapy for the primitive tumors. Tumor extirpations (choroidal, cillary body, or iris tumors) using laser lancet proved to be more suitable than classic surgery.

  9. Intraocular pressure reduction and regulation system

    NASA Technical Reports Server (NTRS)

    Baehr, E. F.; Burnett, J. E.; Felder, S. F.; Mcgannon, W. J.

    1979-01-01

    An intraocular pressure reduction and regulation system is described and data are presented covering performance in: (1) reducing intraocular pressure to a preselected value, (2) maintaining a set minimum intraocular pressure, and (3) reducing the dynamic increases in intraocular pressure resulting from external loads applied to the eye.

  10. Intraocular pressure reduction and regulation

    NASA Technical Reports Server (NTRS)

    Baehr, E. F.; Mcgannon, W. J.

    1979-01-01

    System designed to reduce intraocular pressure hydraulically to any level desired by physician over set time and in controlled manner has number of uses in ophthalmology. Device may be most immediately useful in treatment of glaucoma.

  11. The control of aniseikonia after intraocular lens implantation.

    PubMed

    Hillman, J S; Hawkswell, A

    1985-01-01

    This paper reports a study of postoperative refraction and eikonometry of 50 patients who had unilateral cataract extraction with implantation of a pupil-supported intraocular lens. The mean postoperative aniseikonia (+/- SD) was 1.97 (+/- 1.82). A statistically significant relationship was shown between anisometropia and aniseikonia. Despite aniseikonia of up to 7.8 per cent there were no diplopia problems as the visual system exhibits a high degree of tolerance. It is concluded that aniseikonia can be controlled to within clinically acceptable limits by the simple calculation of intraocular lens power for isometropia.

  12. [Experimental investigations on the mode of action of alcoholic liquor on the intra-ocular pressure (author's transl)].

    PubMed

    Leydhecker, W; Krieglstein, G K; Uhlich, E

    1978-07-01

    The reasons for the decrease of intraocular pressure after drinking of alcohol were examined. The dose of alcohol was 2 ml 38% Weinbrand per kg body weight, which corresponds to 53 ml pure alcohol for a person of 70 kg body weight. The tonographic data gave no correlation between the blood-alcohol level and the changes of intraocular pressure. The antidiuretic hormon also had no correlation to the intraocular pressure changes. Tonometry with the same frequency as in this study but without alcohol showed no alteration of intraocular pressure. It is suggested that alcohol acts probably by a decrease of secretion of aqueous humour by central actions.

  13. Far-field brainstem responses evoked by vestibular and auditory stimuli exhibit increases in interpeak latency as brain temperature is decreased

    NASA Technical Reports Server (NTRS)

    Hoffman, L. F.; Horowitz, J. M.

    1984-01-01

    The effect of decreasing of brain temperature on the brainstem auditory evoked response (BAER) in rats was investigated. Voltage pulses, applied to a piezoelectric crystal attached to the skull, were used to evoke stimuli in the auditory system by means of bone-conducted vibrations. The responses were recorded at 37 C and 34 C brain temperatures. The peaks of the BAER recorded at 34 C were delayed in comparison with the peaks from the 37 C wave, and the later peaks were more delayed than the earlier peaks. These results indicate that an increase in the interpeak latency occurs as the brain temperature is decreased. Preliminary experiments, in which responses to brief angular acceleration were used to measure the brainstem vestibular evoked response (BVER), have also indicated increases in the interpeak latency in response to the lowering of brain temperature.

  14. Softec HD hydrophilic acrylic intraocular lens: biocompatibility and precision.

    PubMed

    Espandar, Ladan; Sikder, Shameema; Moshirfar, Majid

    2011-01-10

    Intraocular lens development is driven by higher patient expectations for ideal visual outcomes. The recently US Food and Drug Administration-approved Softec HD(™) lens is an aspheric, hydrophilic acrylic intraocular lens (IOL). The hydrophilic design of the lens is optimized to address dysphotopsia while maintaining biocompatibility, optical clarity, resistance to damage, and resistance to biocontamination. Aspheric lenses decrease postoperative spherical aberration. The addition of the Softec lens provides clinicians with another option for IOL placement; however, randomized comparative studies of this lens to others already on the market remain to be completed.

  15. Softec HD hydrophilic acrylic intraocular lens: biocompatibility and precision

    PubMed Central

    Espandar, Ladan; Sikder, Shameema; Moshirfar, Majid

    2011-01-01

    Intraocular lens development is driven by higher patient expectations for ideal visual outcomes. The recently US Food and Drug Administration-approved Softec HD™ lens is an aspheric, hydrophilic acrylic intraocular lens (IOL). The hydrophilic design of the lens is optimized to address dysphotopsia while maintaining biocompatibility, optical clarity, resistance to damage, and resistance to biocontamination. Aspheric lenses decrease postoperative spherical aberration. The addition of the Softec lens provides clinicians with another option for IOL placement; however, randomized comparative studies of this lens to others already on the market remain to be completed. PMID:21311658

  16. Men with Sickle Cell Anemia and Priapism Exhibit Increased Hemolytic Rate, Decreased Red Blood Cell Deformability and Increased Red Blood Cell Aggregate Strength

    PubMed Central

    Cita, Kizzy-Clara; Brureau, Laurent; Lemonne, Nathalie; Billaud, Marie; Connes, Philippe; Ferdinand, Séverine; Tressières, Benoit; Tarer, Vanessa; Etienne-Julan, Maryse; Blanchet, Pascal; Elion, Jacques; Romana, Marc

    2016-01-01

    Objectives To investigate the association between priapism in men with sickle cell anemia (SCA) and hemorheological and hemolytical parameters. Materials and Methods Fifty-eight men with SCA (median age: 38 years) were included; 28 who had experienced priapism at least once during their life (priapism group) and 30 who never experienced this complication (control group). Twenty-two patients were treated with hydroxycarbamide, 11 in each group. All patients were at steady state at the time of inclusion. Hematological and biochemical parameters were obtained through routine procedures. The Laser-assisted Optical Rotational Cell Analyzer was used to measure red blood cell (RBC) deformability at 30 Pa (ektacytometry) and RBC aggregation properties (laser backscatter versus time). Blood viscosity was measured at a shear rate of 225 s-1 using a cone/plate viscometer. A principal component analysis was performed on 4 hemolytic markers (i.e., lactate dehydrogenase (LDH), aspartate aminotransferase (ASAT), total bilirubin (BIL) levels and reticulocyte (RET) percentage) to calculate a hemolytic index. Results Compared to the control group, patients with priapism exhibited higher ASAT (p = 0.01), LDH (p = 0.03), RET (p = 0.03) levels and hemolytic indices (p = 0.02). Higher RBC aggregates strength (p = 0.01) and lower RBC deformability (p = 0.005) were observed in patients with priapism compared to controls. After removing the hydroxycarbamide-treated patients, RBC deformability (p = 0.01) and RBC aggregate strength (p = 0.03) were still different between the two groups, and patients with priapism exhibited significantly higher hemolytic indices (p = 0.01) than controls. Conclusion Our results confirm that priapism in SCA is associated with higher hemolytic rates and show for the first time that this complication is also associated with higher RBC aggregate strength and lower RBC deformability. PMID:27145183

  17. Primary cilia signaling mediates intraocular pressure sensation.

    PubMed

    Luo, Na; Conwell, Michael D; Chen, Xingjuan; Kettenhofen, Christine Insinna; Westlake, Christopher J; Cantor, Louis B; Wells, Clark D; Weinreb, Robert N; Corson, Timothy W; Spandau, Dan F; Joos, Karen M; Iomini, Carlo; Obukhov, Alexander G; Sun, Yang

    2014-09-02

    Lowe syndrome is a rare X-linked congenital disease that presents with congenital cataracts and glaucoma, as well as renal and cerebral dysfunction. OCRL, an inositol polyphosphate 5-phosphatase, is mutated in Lowe syndrome. We previously showed that OCRL is involved in vesicular trafficking to the primary cilium. Primary cilia are sensory organelles on the surface of eukaryotic cells that mediate mechanotransduction in the kidney, brain, and bone. However, their potential role in the trabecular meshwork (TM) in the eye, which regulates intraocular pressure, is unknown. Here, we show that TM cells, which are defective in glaucoma, have primary cilia that are critical for response to pressure changes. Primary cilia in TM cells shorten in response to fluid flow and elevated hydrostatic pressure, and promote increased transcription of TNF-α, TGF-β, and GLI1 genes. Furthermore, OCRL is found to be required for primary cilia to respond to pressure stimulation. The interaction of OCRL with transient receptor potential vanilloid 4 (TRPV4), a ciliary mechanosensory channel, suggests that OCRL may act through regulation of this channel. A novel disease-causing OCRL allele prevents TRPV4-mediated calcium signaling. In addition, TRPV4 agonist GSK 1016790A treatment reduced intraocular pressure in mice; TRPV4 knockout animals exhibited elevated intraocular pressure and shortened cilia. Thus, mechanotransduction by primary cilia in TM cells is implicated in how the eye senses pressure changes and highlights OCRL and TRPV4 as attractive therapeutic targets for the treatment of glaucoma. Implications of OCRL and TRPV4 in primary cilia function may also shed light on mechanosensation in other organ systems.

  18. Primary cilia signaling mediates intraocular pressure sensation

    PubMed Central

    Luo, Na; Conwell, Michael D.; Chen, Xingjuan; Kettenhofen, Christine Insinna; Westlake, Christopher J.; Cantor, Louis B.; Wells, Clark D.; Weinreb, Robert N.; Corson, Timothy W.; Spandau, Dan F.; Joos, Karen M.; Iomini, Carlo; Obukhov, Alexander G.; Sun, Yang

    2014-01-01

    Lowe syndrome is a rare X-linked congenital disease that presents with congenital cataracts and glaucoma, as well as renal and cerebral dysfunction. OCRL, an inositol polyphosphate 5-phosphatase, is mutated in Lowe syndrome. We previously showed that OCRL is involved in vesicular trafficking to the primary cilium. Primary cilia are sensory organelles on the surface of eukaryotic cells that mediate mechanotransduction in the kidney, brain, and bone. However, their potential role in the trabecular meshwork (TM) in the eye, which regulates intraocular pressure, is unknown. Here, we show that TM cells, which are defective in glaucoma, have primary cilia that are critical for response to pressure changes. Primary cilia in TM cells shorten in response to fluid flow and elevated hydrostatic pressure, and promote increased transcription of TNF-α, TGF-β, and GLI1 genes. Furthermore, OCRL is found to be required for primary cilia to respond to pressure stimulation. The interaction of OCRL with transient receptor potential vanilloid 4 (TRPV4), a ciliary mechanosensory channel, suggests that OCRL may act through regulation of this channel. A novel disease-causing OCRL allele prevents TRPV4-mediated calcium signaling. In addition, TRPV4 agonist GSK 1016790A treatment reduced intraocular pressure in mice; TRPV4 knockout animals exhibited elevated intraocular pressure and shortened cilia. Thus, mechanotransduction by primary cilia in TM cells is implicated in how the eye senses pressure changes and highlights OCRL and TRPV4 as attractive therapeutic targets for the treatment of glaucoma. Implications of OCRL and TRPV4 in primary cilia function may also shed light on mechanosensation in other organ systems. PMID:25143588

  19. Intraocular pressure in cats is lowered by drops of hornet venom.

    PubMed

    Kam, J; Waron, M; Barishak, Y R; Schachner, E; Ishay, J S

    1989-01-01

    1. Nine cats were given an intravenous injection of the Oriental hornet (Vespa orientalis, Vespinae; Hymenoptera) venom sac extract (VSE) and seven cats had the same VSE administered as eye drops. 2. When injected intravenously, the hornet VSE decreased the intraocular pressure in both eyes sharply during the first 20 min and with a slower rate later on until the end of the 3 hr experiment. The intraocular pressure dropped to zero in some cases. 3. VSE eye drops decreased the intraocular pressure only in the treated eye, while in the second eye (left as a control) the intraocular pressure remained the same throughout the experiment. 4. The decrease in the intraocular pressure was sharp during the first 20 min and slowed down afterwards until the end of the experiment. 5. The intraocular pressure did not reduce to zero. 6. This study shows that the active components of the hornet venom which caused a decrease in the intraocular pressure can cross the cornea and exert a hypotensive effect in the eye.

  20. Cultured senescent myoblasts derived from human vastus lateralis exhibit normal mitochondrial ATP synthesis capacities with correlating concomitant ROS production while whole cell ATP production is decreased.

    PubMed

    Minet, Ariane D; Gaster, Michael

    2012-06-01

    The free radical theory of aging says that increased oxidative stress and mitochondrial dysfunction are associated with old age. In the present study we have investigated the effects of cellular senescence on muscle energetic by comparing mitochondrial content and function in cultured muscle satellite cells at early and late passage numbers. We show that cultured muscle satellite cells undergoing senescence express a reduced mitochondrial mass, decreased whole cell ATP level, normal to increased mitochondrial ATP production under ATP utilization, increased mitochondrial membrane potential and increased superoxide/mitochondrial mass and hydrogen peroxide/mitochondrial mass ratios. Moreover, the increased ROS production correlates with the corresponding mitochondrial ATP production. Thus, myotubes differentiated from human myoblasts undergoing senescence have a reduced mitochondrial content, but the existent mitochondria express normal to increased functional capabilities. The present data suggest that the origin of aging lies outside the mitochondria and that a malfunction in the cell might be preceding and initiating the increase of mitochondrial ATP synthesis and concomitant ROS production in the single mitochondrion in response to decreased mitochondrial mass and reduced extra-mitochondrial energy supply. This then can lead to the increased damage of DNA, lipids and proteins of the mitochondria as postulated by the free radical theory of aging.

  1. 21 CFR 886.4270 - Intraocular gas.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Intraocular gas. 886.4270 Section 886.4270 Food... DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4270 Intraocular gas. (a) Identification. An intraocular gas is a device consisting of a gaseous fluid intended to be introduced into the eye to place...

  2. 21 CFR 886.4270 - Intraocular gas.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Intraocular gas. 886.4270 Section 886.4270 Food... DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4270 Intraocular gas. (a) Identification. An intraocular gas is a device consisting of a gaseous fluid intended to be introduced into the eye to place...

  3. 21 CFR 886.4270 - Intraocular gas.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Intraocular gas. 886.4270 Section 886.4270 Food... DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4270 Intraocular gas. (a) Identification. An intraocular gas is a device consisting of a gaseous fluid intended to be introduced into the eye to place...

  4. 21 CFR 886.4270 - Intraocular gas.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Intraocular gas. 886.4270 Section 886.4270 Food... DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4270 Intraocular gas. (a) Identification. An intraocular gas is a device consisting of a gaseous fluid intended to be introduced into the eye to place...

  5. 21 CFR 886.4270 - Intraocular gas.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Intraocular gas. 886.4270 Section 886.4270 Food... DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4270 Intraocular gas. (a) Identification. An intraocular gas is a device consisting of a gaseous fluid intended to be introduced into the eye to place...

  6. 21 CFR 886.3600 - Intraocular lens.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Intraocular lens. 886.3600 Section 886.3600 Food... DEVICES OPHTHALMIC DEVICES Prosthetic Devices § 886.3600 Intraocular lens. (a) Identification. An intraocular lens is a device made of materials such as glass or plastic intended to be implanted to...

  7. 21 CFR 886.3600 - Intraocular lens.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Intraocular lens. 886.3600 Section 886.3600 Food... DEVICES OPHTHALMIC DEVICES Prosthetic Devices § 886.3600 Intraocular lens. (a) Identification. An intraocular lens is a device made of materials such as glass or plastic intended to be implanted to...

  8. 21 CFR 886.3600 - Intraocular lens.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Intraocular lens. 886.3600 Section 886.3600 Food... DEVICES OPHTHALMIC DEVICES Prosthetic Devices § 886.3600 Intraocular lens. (a) Identification. An intraocular lens is a device made of materials such as glass or plastic intended to be implanted to...

  9. 21 CFR 886.3600 - Intraocular lens.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Intraocular lens. 886.3600 Section 886.3600 Food... DEVICES OPHTHALMIC DEVICES Prosthetic Devices § 886.3600 Intraocular lens. (a) Identification. An intraocular lens is a device made of materials such as glass or plastic intended to be implanted to...

  10. 21 CFR 886.3600 - Intraocular lens.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Intraocular lens. 886.3600 Section 886.3600 Food... DEVICES OPHTHALMIC DEVICES Prosthetic Devices § 886.3600 Intraocular lens. (a) Identification. An intraocular lens is a device made of materials such as glass or plastic intended to be implanted to...

  11. Intraocular nematodiasis caused by Parelaphostrongylus tenuis in an eland antelope (Taurotragus oryx).

    PubMed

    Gandolf, A Rae; Atkinson, Mark W; Gemensky, Anne J; Hayes, Jeff; Grimes, Sheila; Blumer, Evan S

    2003-06-01

    A 10-mo-old female eland (Taurotragus oryx) at the Wilds exhibited recalcitrant, progressive unilateral uveitis for a 5-wk period, despite constant medical treatment. Unilateral enucleation was performed because of blindness and animal discomfort evidenced by continuous blepharospasm. Histopathologic examination of the eye demonstrated intraocular larvae morphologically consistent with Parelaphostrongylus tenuis, the first known case of intraocular P. tenuis migration. This animal subsequently was euthanatized because of severe, nonresponsive neurologic signs associated with P. tenuis infection.

  12. The Fyodorov Sputnik intraocular lens.

    PubMed

    Kwitko, M L

    1979-04-01

    The author has implanted 197 Fyodorov intraocular lenses. With careful selection of patients, good surgical judgment, and meticulous surgery, a degree of success can be obtained with this lens, which will equal that of conventional cataract surgery. The surgical technique of implantation will be described.

  13. Intraocular tumors. A cytopathologic study.

    PubMed

    Scroggs, M W; Johnston, W W; Klintworth, G K

    1990-01-01

    The cytologic characteristics and histopathologic correlates of common ocular tumors were examined using (1) cytologic and histologic specimens prepared from enucleated eyes with retinoblastoma and melanoma, (2) cytologic specimens prepared from clinically obtained intraocular fluids from eyes with lymphoma, metastatic adenocarcinoma and retinoblastoma and (3) cytologic specimens prepared from orbital aspirates and cerebrospinal fluids from a patient in whom retinoblastoma had spread to the orbit and central nervous system. Retinoblastoma cells occurred singly and in clusters and were associated with abundant necrotic debris and portions of capillaries with perivascular tumor infiltrates. Melanoma cells frequently had prominent nucleoli and variable amounts of fine cytoplasmic pigmentation and were found individually and in groups. Lymphoma cells were noncohesive, with scant cytoplasm. Metastatic intraocular adenocarcinoma cells had well-defined borders, multiple nucleoli and vacuolated cytoplasm. In general, the cellular morphology in the cytologic and tissue preparations of the intraocular tumors correlated well with each other. The findings suggest that common primary and metastatic intraocular tumors can be differentiated in cytologic preparations.

  14. Ultrashort laser ablation of PMMA and intraocular lenses

    NASA Astrophysics Data System (ADS)

    Serafetinides, A. A.; Makropoulou, M.; Fabrikesi, E.; Spyratou, E.; Bacharis, C.; Thomson, R. R.; Kar, A. K.

    2008-10-01

    The use of intraocular lenses (IOLs) is the most promising method to restore vision after cataract surgery. Several new materials, techniques, and patterns have been studied for forming and etching IOLs to improve their optical properties and reduce diffractive aberrations. This study is aimed at investigating the use of ultrashort laser pulses to ablate the surface of PMMA and intraocular lenses, and thus provide an alternative to conventional techniques. Ablation experiments were conducted using various polymer substrates (PMMA samples, hydrophobic acrylic IOL, yellow azo dye doped IOL, and hydrophilic acrylic IOL consist of 25% H2O). The irradiation was performed using 100 fs pulses of 800 nm radiation from a regeneratively amplified Ti:sapphire laser system. We investigated the ablation efficiency and the phenomenology of the ablated patterns by probing the ablation depth using a profilometer. The surface modification was examined using a high resolution optical microscope (IOLs) or atomic force microscope—AFM (PMMA samples). It was found that different polymers exhibited different ablation characteristics, a result that we attribute to the differing optical properties of the materials. In particular, it was observed that the topography of the ablation tracks created on the hydrophilic intraocular lenses was smoother in comparison to those created on the PMMA and hydrophobic lens. The yellow doped hydrophobic intraocular lenses show higher ablation efficiency than undoped hydrophobic acrylic lenses.

  15. Intraocular scattering compensation in retinal imaging.

    PubMed

    Christaras, Dimitrios; Ginis, Harilaos; Pennos, Alexandros; Artal, Pablo

    2016-10-01

    Intraocular scattering affects fundus imaging in a similar way that affects vision; it causes a decrease in contrast which depends on both the intrinsic scattering of the eye but also on the dynamic range of the image. Consequently, in cases where the absolute intensity in the fundus image is important, scattering can lead to a wrong estimation. In this paper, a setup capable of acquiring fundus images and estimating objectively intraocular scattering was built, and the acquired images were then used for scattering compensation in fundus imaging. The method consists of two parts: first, reconstruct the individual's wide-angle Point Spread Function (PSF) at a specific wavelength to be used within an enhancement algorithm on an acquired fundus image to compensate for scattering. As a proof of concept, a single pass measurement with a scatter filter was carried out first and the complete algorithm of the PSF reconstruction and the scattering compensation was applied. The advantage of the single pass test is that one can compare the reconstructed image with the original one and see the validity, thus testing the efficiency of the method. Following the test, the algorithm was applied in actual fundus images in human eyes and the effect on the contrast of the image before and after the compensation was compared. The comparison showed that depending on the wavelength, contrast can be reduced by 8.6% under certain conditions.

  16. Intraocular scattering compensation in retinal imaging

    PubMed Central

    Christaras, Dimitrios; Ginis, Harilaos; Pennos, Alexandros; Artal, Pablo

    2016-01-01

    Intraocular scattering affects fundus imaging in a similar way that affects vision; it causes a decrease in contrast which depends on both the intrinsic scattering of the eye but also on the dynamic range of the image. Consequently, in cases where the absolute intensity in the fundus image is important, scattering can lead to a wrong estimation. In this paper, a setup capable of acquiring fundus images and estimating objectively intraocular scattering was built, and the acquired images were then used for scattering compensation in fundus imaging. The method consists of two parts: first, reconstruct the individual’s wide-angle Point Spread Function (PSF) at a specific wavelength to be used within an enhancement algorithm on an acquired fundus image to compensate for scattering. As a proof of concept, a single pass measurement with a scatter filter was carried out first and the complete algorithm of the PSF reconstruction and the scattering compensation was applied. The advantage of the single pass test is that one can compare the reconstructed image with the original one and see the validity, thus testing the efficiency of the method. Following the test, the algorithm was applied in actual fundus images in human eyes and the effect on the contrast of the image before and after the compensation was compared. The comparison showed that depending on the wavelength, contrast can be reduced by 8.6% under certain conditions. PMID:27867710

  17. An ultralow power wireless intraocular pressure monitoring system

    NASA Astrophysics Data System (ADS)

    Demeng, Liu; Niansong, Mei; Zhaofeng, Zhang

    2014-10-01

    This paper describes an ultralow power wireless intraocular pressure (IOP) monitoring system that is dedicated to sensing and transferring intraocular pressure of glaucoma patients. Our system is comprised of a capacitive pressure sensor, an application-specific integrated circuit, which is designed on the SMIC 180 nm process, and a dipole antenna. The system is wirelessly powered and demonstrates a power consumption of 7.56 μW at 1.24 V during continuous monitoring, a significant reduction in active power dissipation compared to existing work. The input RF sensitivity is -13 dBm. A significant reduction in input RF sensitivity results from the reduction of mismatch time of the ASK modulation caused by FM0 encoding. The system exhibits an average error of ± 1.5 mmHg in measured pressure. Finally, a complete IOP system is demonstrated in the real biological environment, showing a successful reading of the pressure of an eye.

  18. Phakic Intraocular Lenses and their Special Indications

    PubMed Central

    Pineda, Roberto; Chauhan, Tulika

    2016-01-01

    Phakic intraocular lenses revolutionize refractive surgery and continue to serve as an excellent option for vision correction in patients who are not ideal candidates for laser vision correction. This article will review special indications of phakic intraocular lenses in the clinical practice. PMID:27994811

  19. Intraocular retinal prosthesis.

    PubMed Central

    Humayun, M S

    2001-01-01

    stimulus duration (P < .05). In all groups, short duration pulses (40, 80, and 120 microseconds) were more efficient in terms of total charge (the product of pulse amplitude and pulse duration) than longer (500 and 1,000 microseconds) pulses (P < .05). In all groups, applying a pulse train did not lead to more efficient charge usage (P < .05). Psychophysical experiments: In high-contrast tests, facial recognition rates of over 75% were achieved for all subjects with dot sizes of up to 31.5 minutes of arc when using a 25 x 25 grid with 4.5 arc minute gaps, a 30% dropout rate, and 6 gray levels. Even with a 4 x 4 array of pixels, some subjects were able to accurately describe 2 of the objects. Subjects who were able to read the 4-pixel letter height sentences (on the 6 x 10 and 16 x 16 array) seemed to have a good scanning technique. Scanning at the proper velocity tends to bring out more contrast in the lettering. The reading speed for the 72-point font is a bit slower than for the next smaller font. This may be due to the limited number of letters (3) visible in the window with this large font. CONCLUSIONS: Specific parameters needed to stimulate the retina were identified. Delineating the optimum parameters will decrease the current requirements. Psychophysical tests show that with limited pixels and image processing, useful vision is possible. Both these findings should greatly simplify the engineering of an electronic retinal prosthesis. PMID:11797315

  20. IRIS: Integrated Robotic Intraocular Snake*

    PubMed Central

    He, Xingchi; van Geirt, Vincent; Gehlbach, Peter; Taylor, Russell; Iordachita, Iulian

    2015-01-01

    Retinal surgery is one of the most technically challenging surgical disciplines. Many robotic systems have been developed to enhance the surgical capabilities. However, very few of them provide the surgeon the dexterity within the patient’s eye to enable more flexible, more advanced surgical procedures. This paper presents a sub-millimeter intraocular dexterous robot, the Integrated Robotic Intraocular Snake (IRIS). The variable neutral-line mechanism is used to provide very high dexterity with a very small form factor. The IRIS distal dexterous unit is 0.9 mm in diameter and about 3 mm in length. It enables two rotational degrees of freedom at the distal end of the ophthalmic instruments. The analysis on contact mechanics provides a reference for the adjustment of the wire pretension. Redundant actuation is implemented by using one motor for each wire. A motion scaling transmission is developed to overcome the suboptimal resolution of the motors. A scale-up model of the IRIS is built for initial experimental evaluation. Preliminary results show that the scale-up IRIS can provide large range of motion. For given bending angle, the kinematic model can estimate the desired wire translation when the friction is not significant. The first prototype of the actual-scale IRIS is assembled and tested. PMID:26405561

  1. Transillumination imaging of intraocular tumours.

    PubMed

    Kjersem, Bård; Krohn, Jørgen

    2013-06-01

    The purpose of this paper is to discuss a recently described modification of a standard photo slit lamp system for ocular transillumination, with special emphasis on the light transmission through the eye wall and the photographic technique. Transillumination photography was carried out with the Haag-Streit Photo-Slit Lamp BX 900 (Haag-Streit AG, Koeniz, Switzerland). After having released the background lighting optic fibre cable from its holder, the patient was positioned at the slit lamp, and the fibre tip was gently pressed against the sclera or the cornea of the patient's eye. During about 1/1000 of a second, the eye was illuminated by the flash and the scleral shadow of the tumour was exposed to the camera sensor. The images were of good diagnostic quality, making it easy to outline the tumours and to evaluate the involvement of intraocular structures. None of the examined patients experienced discomfort or negative side effects. The method is recommended in cases where photographic transillumination documentation of intraocular pathologies is considered important.

  2. Stability of Adrenaline in Irrigating Solution for Intraocular Surgery.

    PubMed

    Shibata, Yuuka; Kimura, Yasuhiro; Taogoshi, Takanori; Matsuo, Hiroaki; Kihira, Kenji

    2016-01-01

    Intraocular irrigating solution containing 1 µg/mL adrenaline is widely used during cataract surgery to maintain pupil dilation. Prepared intraocular irrigating solutions are recommended for use within 6 h. After the irrigating solution is admistered for dilution, the adrenaline may become oxidized, and this may result in a decrease in its biological activity. However, the stability of adrenaline in intraocular irrigating solution is not fully understood. The aim of this study was to evaluate the stability of adrenaline in clinically used irrigating solutions of varying pH. Six hours after mixing, the adrenaline percentages remaining were 90.6%±3.7 (pH 7.2), 91.1%±2.2 (pH 7.5), and 65.2%±2.8 (pH 8.0) of the initial concentration. One hour after mixing, the percentages remaining were 97.6%±2.0 (pH 7.2), 97.4%±2.7 (pH 7.5), and 95.6%±3.3 (pH 8.0). The degradation was especially remarkable and time dependent in the solution at pH 8.0. These results indicate that the concentration of adrenaline is decreased after preparation. Moreover, we investigated the influence of sodium bisulfite on adrenaline stability in irrigating solution. The percentage adrenaline remaining at 6 h after mixing in irrigating solution (pH 8.0) containing sodium bisulfite at 0.5 µg/mL (concentration in irrigating solution) or at 500 µg/mL (concentration in the undiluted adrenaline preparation) were 57.5 and 97.3%, respectively. Therefore, the low concentration of sodium bisulfite in the irrigating solution may be a cause of the adrenaline loss. In conclusion, intraocular irrigation solution with adrenaline should be prepared just prior to its use in surgery.

  3. Applications of polymers in intraocular drug delivery systems

    PubMed Central

    Alhalafi, Ali Mohammed

    2017-01-01

    We are entering a new era of ophthalmic pharmacology where new drugs are rapidly being developed for the treatment of anterior and posterior segment of the eye disease. The pharmacokinetics of drug delivery to the eye remains a very active area of ophthalmic research. Intraocular drug delivery systems allow the release of the drug, bypassing the blood-ocular barrier. The main advantage of these preparations is that they can release the drug over a long time with one single administration. These pharmaceutical systems are of great important in the treatment of the posterior segment diseases, and they can be prepared from biodegradable or nonbiodegradable polymers. Biodegradable polymers have the advantage of disappearing from the site of action after releasing the drug. The majority of intraocular devices are prepared from nonbiodegradable polymers, and they can release controlled amounts of drugs for months. Nonbiodegradable polymers include silicone, polyvinyl alcohol, and ethylene-vinyl acetate. The polymers usually employed to prepare nanoparticles for the topical ophthalmic route are poly (acrylic acid) derivatives (polyalquilcyanocrylates), albumin, poly-ε-caprolactone, and chitosan. Dendrimers are a recent class of polymeric materials with unique nanostructure which has been studied to discover their role in the delivery of therapeutics and imaging agents. Hydrogels are polymers that can swell in aqueous solvent system, and they hold the solvents in a swollen cross-linked gel for delivery. This review exhibits the current literature regarding applications of polymers in ophthalmic drug delivery systems including pharmacokinetics, advantages, disadvantages, and indications aimed to obtain successful eye therapy. Method of Literature Search: A systematic literature review was performed using PubMed databases into two steps. The first step was oriented to classification of intraocular polymers implants focusing on their advantages and disadvantages. The second

  4. Exhibiting Lives

    ERIC Educational Resources Information Center

    Golden, Deborah; Elbaz-Luwisch, Freema

    2007-01-01

    This paper examines some of the dilemmas that accompany the emergence of the personal voice in scholarly work, by taking a close, grounded look at the way in which these unfolded in a specific academic course. As part of the course, entitled "A cultural approach to the life cycle", students were asked to participate in a group exhibition in which…

  5. Unilateral retinopathy secondary to occult primary intraocular lymphoma

    PubMed Central

    Barile, Gaetano R.; Hood, Donald C.; Marr, Brian; Hussein, Shafinaz; Tsang, Stephen H.

    2014-01-01

    Purpose The purpose of the study is to report the clinical case of a 53-year-old woman whose presenting manifestation of primary intraocular lymphoma (PIOL) was unilateral retinal degeneration. Method A case report was created with review of clinical, imaging, electrophysiologic, and pathological investigations. Results A 53-year-old woman with a distant history of ocular herpes simplex developed progressive central visual loss and intermittent photopsia over 4 years in her right eye. Ophthalmic examination revealed reduced visual acuity OD, central scotoma, and minimal ocular findings. Autofluorescence and infrared imaging revealed mild reflectance changes in the temporal macula, and spectral-domain optical coherence tomography identified mild disruptions of inner segment/outer segment junctions in the subfoveal region of the right eye. A mild window defect was seen on fluorescein angiography. Electrophysiology with multifocal electroretinogram (ERG) revealed evidence of unilateral macular dysfunction. Full-field ERGs revealed progressive global retinal dysfunction over 6 months, with unilateral decreases in amplitude and implicit time shifts, as seen in cases of autoimmune retinopathies. The eye eventually exhibited mild vitreous cellular infiltration on ophthalmoscopic examination, and vitrectomy diagnosed B cell non-Hodgkin’s lymphoma. Further evaluation revealed no evidence of central nervous system or systemic disease, consistent with occult PIOL. Conclusions This case illustrates an atypical presentation of PIOL characterized by unilateral retinal disease presenting with symptoms and signs of macular dysfunction. Clinical and ERG features evolved into an acute zonal occult outer retinopathy (AZOOR)-like phenotype. PIOL should be considered in atypical cases of AZOOR with vitreal reactions, and some cases of AZOOR may be related to B cell lymphocyte disorders. PMID:24081663

  6. Intraocular pressure in very low birth weight preterm infants and its association with postconceptional age

    PubMed Central

    Lindenmeyer, Rodrigo L.; Farias, Lucas; Mendonça, Taís; Filho, João Borges Fortes; Procianoy, Renato S.; Silveira, Rita C.

    2012-01-01

    OBJECTIVE: To evaluate intraocular pressure in very low birth weight preterm infants and correlate it with postconceptional age. METHODS: The intraocular pressure in a prospective cohort of very low birth weight premature infants (defined as a birth weight ≤1,500 g and gestational age ≤32 weeks) admitted to Hospital de Clínicas de Porto Alegre, Brazil was evaluated weekly. The evaluated outcome was the variation in the intraocular pressure following changes in the postconceptional age (defined as the gestational age at birth plus the age in weeks at the time of examination) in the weeks following preterm birth. Mixed-effects models were used for the statistical analysis to determine the intraocular pressure variation according to postconceptional age, and means and 10th and 90th percentiles were calculated for the intraocular pressure values. RESULTS: Fifty preterm infants with a mean gestational age of 29.7±1.6 weeks and a mean birth weight of 1,127.7±222.7 g were evaluated. The mean intraocular pressure for the entire cohort considering both eyes was 14.9±4.5 mmHg, and 13.5% of all recorded intraocular pressure values were greater than 20 mmHg. The analysis revealed a mean reduction in the intraocular pressure of 0.29 mmHg for each increase in postconceptional age (p = 0.047; 95% CI: −0.58 to −0.0035). The mean intraocular pressure (P10–P90) decreased from 16.3 mmHg (10.52–22.16) at 26.3 weeks to 13.1 mmHg (7.28–18.92) at 37.6 weeks of postconceptional age. CONCLUSIONS: The mean intraocular pressure in very low birth weight preterm infants was 14.9±4.5 mmHg. This value decreased 0.29 mmHg per week as the postconceptional age increased. PMID:23184197

  7. Pediatric patients with inflammatory bowel disease exhibit increased serum levels of proinflammatory cytokines and chemokines, but decreased circulating levels of macrophage inhibitory protein-1β, interleukin-2 and interleukin-17

    PubMed Central

    KLEINER, GIULIO; ZANIN, VALENTINA; MONASTA, LORENZO; CROVELLA, SERGIO; CARUSO, LORENZO; MILANI, DANIELA; MARCUZZI, ANNALISA

    2015-01-01

    Inflammatory bowel disease (IBD) is a chronic and progressive inflammatory condition of the gastrointestinal tract. Although the causative events that lead to the onset of IBD are yet to be fully elucidated, deregulation of immune and inflammatory mechanisms are hypothesized to significantly contribute to this disorder. Since the onset of IBD is often during infancy, in the present study, the serum values of a large panel of cytokines and chemokines in pediatric patients (<18 years; n=26) were compared with age-matched controls (n=37). While elevations in the serum level of several proinflammatory and immune regulating cytokines were confirmed, such as interleukin (IL)-1β, IL-5, IL-7, interferon (IFN)-γ-inducible protein-10, IL-16, cutaneous T-cell-attracting chemokine, leukemia inhibitory factor, monokine induced by γ-IFN, IFN-α2 and IFN-γ, notably decreased levels of IL-2, IL-17 and macrophage inhibitory protein-1β were also observed. Therefore, while a number of proinflammatory cytokines exhibit increased levels in IBD patients, pediatric IBD patients may also exhibit certain aspects of a reduced immunological response. PMID:26136934

  8. Pediatric patients with inflammatory bowel disease exhibit increased serum levels of proinflammatory cytokines and chemokines, but decreased circulating levels of macrophage inhibitory protein-1β, interleukin-2 and interleukin-17.

    PubMed

    Kleiner, Giulio; Zanin, Valentina; Monasta, Lorenzo; Crovella, Sergio; Caruso, Lorenzo; Milani, Daniela; Marcuzzi, Annalisa

    2015-06-01

    Inflammatory bowel disease (IBD) is a chronic and progressive inflammatory condition of the gastrointestinal tract. Although the causative events that lead to the onset of IBD are yet to be fully elucidated, deregulation of immune and inflammatory mechanisms are hypothesized to significantly contribute to this disorder. Since the onset of IBD is often during infancy, in the present study, the serum values of a large panel of cytokines and chemokines in pediatric patients (<18 years; n=26) were compared with age-matched controls (n=37). While elevations in the serum level of several proinflammatory and immune regulating cytokines were confirmed, such as interleukin (IL)-1β, IL-5, IL-7, interferon (IFN)-γ-inducible protein-10, IL-16, cutaneous T-cell-attracting chemokine, leukemia inhibitory factor, monokine induced by γ-IFN, IFN-α2 and IFN-γ, notably decreased levels of IL-2, IL-17 and macrophage inhibitory protein-1β were also observed. Therefore, while a number of proinflammatory cytokines exhibit increased levels in IBD patients, pediatric IBD patients may also exhibit certain aspects of a reduced immunological response.

  9. Museum Exhibit

    NASA Technical Reports Server (NTRS)

    1991-01-01

    A TSP from NASA Tech Briefs provided the solution to an electrical problem at a Florida museum. When a model train would not start without a jerk, a Marshall Space Flight Center development called pulse width control was adapted. The new circuit enables the train to start smoothly and reduces construction and maintenance costs. The same technology is also used in another hands-on exhibit. Applications of other TSPs are anticipated.

  10. [Physical exercise and intraocular pressure].

    PubMed

    Liang, Yuan-bo; Wu, Yue; Li, Si-zhen; Sun, Lan-ping; Wang, Ning-li

    2011-09-01

    In the 1960s, it had been observed that physical exercises could reduce the intraocular pressure (IOP) in patients with glaucoma. However, the effect of IOP reduction varied with exercise type and intensity, as well as the duration after exercise. Difference of lowering the IOP in glaucoma patients and healthy people were also observed. The mechanisms of reducing the IOP by exercise were very complicated and believed to be associated with the lower concentration of norepinephrine, the rising of colloid osmotic pressure, the co-action of nitric oxide and endothelin after exercise, and also related to the gene polymorphism of β2-adrenergic receptor. Physical exercise, such as jogging, walking and bicycle riding, could be suggested as a complimentary therapy in addition to the pharmaceutical and surgical therapies available for glaucoma patients, even though the mechanism for lowering IOP is not clear enough.

  11. UV laser ablation patterns in intraocular lenses

    NASA Astrophysics Data System (ADS)

    Lagiou, D. P.; Evangelatos, Ch.; Apostolopoulos, A.; Spyratou, E.; Bacharis, C.; Makropoulou, M.; Serafetinides, A. A.

    2013-03-01

    The aim of this work is to investigate the effect of UV solid state laser radiation on intraocular lens (IOL) polymer surfaces as an alternative method to conventional surface shaping techniques for IOLs customization. Laser ablation experiments were performed on PMMA plates and commercially available hydrophobic and hydrophilic acrylic IOLs with the 5th harmonic of a Q-switched Nd:YAG laser (λ=213 nm). Circular arrays of holes were drilled on the polymer surface, covering the centre and the peripheries of the IOL. The morphology of the ablated IOL surface was examined with a conventional optical microscope (Leitz GMBH Wetzlar) and with a scanning electron microscope (SEM, Fei - Innova Nanoscope) at various laser parameters. Quantitative measurements of ablation rates were performed with a contact profilometer (Dektak-150), in which a mechanical stylus scanned across the surface of gold-coated IOLs (after SEM imaging) to measure variationsF in surface height. Laser interaction with IOLs depends on optical and mechanical material properties, in addition to laser radiation parameters. The exact ablation mechanism is discussed. Some polymer materials, depending on their properties, are more susceptible to the photothermal mechanism than the photochemical one or vice versa. In summary, every IOL polymer exhibits specific attributes in its interaction with the 5th harmonic of Nd:YAG laser.

  12. Outdoor Exhibits

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The National Data Buoy Center (NDBC) at the John C. Stennis Space Center has exhibits located in front of the Visitors Center. These boat-shaped buoys are moored in areas of the ocean that experience hostile environmental conditions. The instruments installed gather information and relay it to the National Weather Service by satellite. Nomad buoys are 20 feet long and weigh 13,900 pounds. They provide information on wind speed and direction, humidity levels, air and sea surface temperature and air pressure. U.S. Coast Guard ships transport buoys to their mooring sites.

  13. Resection of intraocular squamous cell carcinoma.

    PubMed Central

    Char, D H; Crawford, J B; Howes, E L; Weinstein, A J

    1992-01-01

    A patient with recurrent squamous cell carcinoma of the conjunctiva was referred with 20/20 vision in an eye with obvious intraocular extension. A modified iridocyclochoroidectomy was performed and the tumour was removed. Three and a half years later the patient's vision is 20/30 and there is no recurrence. This is the first case in which an eye has been successfully salvaged with documented intraocular squamous cell carcinoma of the conjunctiva. Images PMID:1739709

  14. Iris fixation of posterior chamber intraocular lenses.

    PubMed

    Yazdani-Abyaneh, Alireza; Djalilian, Ali R; Fard, Masoud Aghsaei

    2016-12-01

    We introduce a technique for iris fixation of a posterior chamber intraocular lens (IOL) in which most of the procedure is done outside the eye. This minimizes intraocular manipulation, maximizes corneal endothelial preservation, and avoids the risk for IOL drop into the vitreous cavity intraoperatively. The IOL is fixated to the most peripheral part of the iris, resulting in a rounder pupil. Sutures are placed at exact positions on the haptics, resulting in a well-centered IOL.

  15. Changes in intraocular pressure after exercise test

    PubMed Central

    Esfahani, Morteza Abdar; Gharipour, Mojgan; Fesharakinia, Hamid

    2017-01-01

    Background: The decrease in intraocular pressure (IOP) within exercise has been recently suggested; however, this change remained ambiguous following exercise test. The present study aimed to assess changes in IOP induced by exercise test in patients who suspected to coronary artery disease (CAD) and indicated for exercise test evaluation. Methods: In a cross-sectional study at the cardiovascular research center of Amin Heart Hospital in Isfahan, 101 eyes from 51 consecutive patients suspected to CAD aged 30–70 years referred for exercise testing were evaluated. IOP was measured at the three time points of before exercise test as well as 5 and 20 min after completing exercise test using Schiotz tonometer. All exercise tests were programmed by the treadmill. Results: The mean IOP in all assessed eyes was 16.12 ± 2.61 mmHg initially that was gradually decreased to 13.79 ± 2.40 mmHg 5 min after the exercise test, but elevated to 15.67 ± 2.26 mmHg 20 min after the test. Assessing IOP following exercise testing showed a significant decrease in IOP in 75 eyes (74.3%), remained unchanged in 19.8% of eyes, and even elevated in 5.9% of eyes. There was a significant direct association between patients' age and IOP changes assessed by the Pearson's correlation test (r = 0.350,P = 0.009). No significant difference was revealed in the trend of the changes in IOP after exercise test between men and women, between left-sided and right-sided eyes as well as between different body mass index subgroups. Conclusion: IOP temporarily reduced after exercise test, but return to baseline value shortly after test. This lowering is more evident in advanced aging. PMID:28298859

  16. Colour vision through intraocular lens.

    PubMed

    Mäntyjärvi, M; Syrjäkoski, J; Tuppurainen, K; Honkonen, V

    1997-04-01

    Fifty patients aged from 30 to 69 years (mean 54.7 +/- 11.3 years, SD) with a UV-protected monofocal polymethylmethacrylate intraocular lens (IOL) were examined with the Farnsworth-Munsell 100 hue (FM 100) test and the Color Vision Meter 712 anomaloscope. The spectral transmission of the same kind of IOLs as was used surgically was measured with Lambda 2 UV/VIS Spectrometer. In the FM 100 test, there was no significant difference between the results of the IOL eyes and normal eyes. However, the IOL eyes showed better error scores than the normal eyes in the blue-purple box IV in the FM 100 test. In the anomaloscope testing, the Rayleigh (red-green) equation showed no differences between the IOL patients and controls. In the Moreland (blue) equation, however, the mid matching point was significantly shifted towards more green (meaning better blue colour sensitivity) in the IOL eyes than in the control eyes. This is due to the spectral transmission of the IOLs which showed 80-90% transmission already starting at the wavelength of about 420 nm. In comparison, the transmission of the normal human lens reaches those percentages near 500 nm or even further at advanced age.

  17. Biopsy techniques for intraocular tumors

    PubMed Central

    Rishi, Pukhraj; Dhami, Abhinav; Biswas, Jyotirmay

    2016-01-01

    Biopsy involves the surgical removal of a tissue specimen for histopathologic evaluation. Most intraocular tumors are reliably diagnosed based on the clinical evaluation or with noninvasive diagnostic techniques. However, accurately diagnosing a small percentage of tumors can be challenging. A tissue biopsy is thus needed to establish a definitive diagnosis and plan the requisite treatment. From fine-needle aspiration biopsy (FNAB) to surgical excision, all tissue collection techniques have been studied in the literature. Each technique has its indications and limitations. FNAB has been reported to provide for 88–95% reliable and safe ophthalmic tumor diagnosis and has gained popularity for prognostic purposes and providing eye conserving treatment surgeries. The technique and instrumentation for biopsy vary depending upon the tissue involved (retina, choroid, subretinal space, vitreous, and aqueous), suspected diagnosis, size, location, associated retinal detachment, and clarity of the media. The cytopathologist confers a very important role in diagnosis and their assistance plays a key role in managing and planning the treatment for malignancies. PMID:27488148

  18. Surface Modification of Intraocular Lenses

    PubMed Central

    Huang, Qi; Cheng, George Pak-Man; Chiu, Kin; Wang, Gui-Qin

    2016-01-01

    Objective: This paper aimed to review the current literature on the surface modification of intraocular lenses (IOLs). Data Sources: All articles about surface modification of IOLs published up to 2015 were identified through a literature search on both PubMed and ScienceDirect. Study Selection: The articles on the surface modification of IOLs were included, but those on design modification and surface coating were excluded. Results: Technology of surface modification included plasma, ion beam, layer-by-layer self-assembly, ultraviolet radiation, and ozone. The main molecules introduced into IOLs surface were poly (ethylene glycol), polyhedral oligomeric silsesquioxane, 2-methacryloyloxyethyl phosphorylcholine, TiO2, heparin, F-heparin, titanium, titanium nitride, vinyl pyrrolidone, and inhibitors of cytokines. The surface modification either resulted in a more hydrophobic lens, a more hydrophilic lens, or a lens with a hydrophilic anterior and hydrophobic posterior surface. Advances in research regarding surface modification of IOLs had led to a better biocompatibility in both in vitro and animal experiments. Conclusion: The surface modification is an efficient, convenient, economic and promising method to improve the biocompatibility of IOLs. PMID:26830993

  19. The genetics of intraocular pressure.

    PubMed

    Ojha, Pallavi; Wiggs, Janey L; Pasquale, Louis R

    2013-01-01

    Glaucoma is a leading cause of irreversible blindness. Intraocular pressure (IOP) is the only modifiable risk factor for glaucoma, yet there is little known about the molecular events that regulate IOP. Genetic and genomic studies have helped identify genes that influence IOP and could lead to the identification of biological pathways that serve as targets for novel pressure-modifying therapies. Genetic linkage studies resulted in the identification of several genes that cause Mendelian (autosomal dominant or autosomal recessive) forms of high-pressure glaucoma, including MYOC. PITX2, FOXC1, and CYP1B1. Classical twin studies suggest that IOP is a heritable trait. More recently, genome-wide association studies (GWAS) have shown that common genetic variants in the GAS7 and TMCO1 genomic regions are associated with elevated IOP. TMCO1 has also been associated with primary open-angle glaucoma in patients with advanced disease. A further study identifying additional genes contributing to IOP will be necessary to fully define the underlying genetic architecture of IOP.

  20. Intraocular eyelashes and iris cyst in anterior chamber following penetrating eye injury: a case report

    PubMed Central

    Sahu, Sabin; Puri, Lila Raj; Singh, Sanjay Kumar

    2017-01-01

    Background The presence of intraocular eyelashes following penetrating eye injury or ocular surgery is relatively uncommon. The response of the eye to intraocular eyelashes is variable. The eyelash may be symptomatic or may remain asymptomatic for long periods. Objective We report a case with two intraocular eyelashes and an iris cyst after 2 years of asymptomatic period following penetrating eye injury. Case presentation A 24-year-old male presented with decreased vision in the left eye which he had noticed for the previous 2 weeks. His visual acuity was 6/6 in the right eye and 6/18 in the left eye, improving to 6/9 with -2.5 DC × 140° correction. The intraocular pressure was 12 mmHg in both eyes. On slit-lamp examination, the left eye showed 8 mm linear peripheral corneal opacity nasally, two eyelashes in the superior anterior chamber, and an iris cyst measuring 4 mm × 4 mm in the superior iris. The right eye was normal. Dilated fundus examination of both eyes was normal. The eyelashes and cyst were removed surgically. There were no complications during the 3-month follow-up period. Conclusion Intraocular implantation of eyelashes following penetrating eye injury can remain asymptomatic for long periods; however, late development of iris cyst may occur. PMID:28356777

  1. Commercial air travel after intraocular gas injection.

    PubMed

    Houston, Stephen; Graf, Jürgen; Sharkey, James

    2012-08-01

    Passengers with intraocular gas are at risk of profound visual loss when exposed to reduced absolute pressure within the cabin of a typical commercial airliner. Information provided on the websites of the world's 10 largest airlines offer a considerable range of opinion as to when it might be safe to fly after gas injection. Physicians responsible for clearing pseassengers as 'fit to fly' should be aware modern retinal surgical techniques increasingly employ long-acting gases as vitreous substitutes. The kinetics of long-acting intraocular gases must be considered when deciding how long after surgery it is safe to travel. It is standard practice to advise passengers not to fly in aircraft until the gas is fully resorbed. To achieve this, it may be necessary to delay travel for approximately 2 wk after intraocular injection of sulfur hexafluoride (SF6) and for 6 wk after injection of perfluoropropane (C3F8).

  2. 21 CFR 886.4300 - Intraocular lens guide.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Intraocular lens guide. 886.4300 Section 886.4300...) MEDICAL DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4300 Intraocular lens guide. (a) Identification. An intraocular lens guide is a device intended to be inserted into the eye during surgery to...

  3. 21 CFR 886.4300 - Intraocular lens guide.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Intraocular lens guide. 886.4300 Section 886.4300...) MEDICAL DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4300 Intraocular lens guide. (a) Identification. An intraocular lens guide is a device intended to be inserted into the eye during surgery to...

  4. 21 CFR 886.4300 - Intraocular lens guide.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Intraocular lens guide. 886.4300 Section 886.4300...) MEDICAL DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4300 Intraocular lens guide. (a) Identification. An intraocular lens guide is a device intended to be inserted into the eye during surgery to...

  5. 21 CFR 886.4300 - Intraocular lens guide.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Intraocular lens guide. 886.4300 Section 886.4300...) MEDICAL DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4300 Intraocular lens guide. (a) Identification. An intraocular lens guide is a device intended to be inserted into the eye during surgery to...

  6. 21 CFR 886.4280 - Intraocular pressure measuring device.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Intraocular pressure measuring device. 886.4280... (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4280 Intraocular pressure measuring device. (a) Identification. An intraocular pressure measuring device is a manual or AC-powered...

  7. 21 CFR 886.4280 - Intraocular pressure measuring device.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Intraocular pressure measuring device. 886.4280... (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4280 Intraocular pressure measuring device. (a) Identification. An intraocular pressure measuring device is a manual or AC-powered...

  8. 21 CFR 886.4280 - Intraocular pressure measuring device.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Intraocular pressure measuring device. 886.4280... (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4280 Intraocular pressure measuring device. (a) Identification. An intraocular pressure measuring device is a manual or AC-powered...

  9. 21 CFR 886.4300 - Intraocular lens guide.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Intraocular lens guide. 886.4300 Section 886.4300...) MEDICAL DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4300 Intraocular lens guide. (a) Identification. An intraocular lens guide is a device intended to be inserted into the eye during surgery to...

  10. Intraocular Pressure Changes With Positioning During Laparoscopy

    PubMed Central

    Onakpoya, Oluwatoyin H.; Adenekan, Anthony T.; Awe, Oluwaseun. O.

    2016-01-01

    Background and Objectives: Pneumoperitoneum during laparoscopy can produce changes in intraocular pressure (IOP) that may be influenced by several factors. In this study, we investigated changes in IOP during laparoscopy with different positioning. Methods: We recruited adult patients without eye disease scheduled to undergo laparoscopic operation requiring a reverse Trendelenburg tilt (rTr; group A; n = 20) or Trendelenburg tilt (Tr; Group B; n = 20). IOP was measured at 7 time points (T1–T7). All procedures were performed with standardized anaesthetic protocol. Mean arterial pressure (MAP), heart rate (HR), peak and plateau airway pressure, and end-tidal carbon dioxide (ETCO2) measurements were taken at each time point. Results: Both groups were similar in age, sex, mean body mass index (BMI), duration of surgery, and preoperative IOP. A decrease in IOP was observed in both groups after induction of anaesthesia (T2), whereas induction of pneumoperitoneum produced a mild increase in IOP (T3) in both groups. The Trendelenburg tilt produced IOP elevations in 80% of patients compared to 45% after the reverse Trendelenburg tilt (P = .012). A significant IOP increase of 5 mm Hg or more was recorded in 3 (15%) patients in the Trendelenburg tilt group and in none in the reverse Trendelenburg group. At T7, IOP had returned to preoperative levels in all but 3 (15%) in the Trendelenburg and 1 (5%) in the reverse Trendelenburg group. Reversible changes were observed in the MAP, HR, ETCO2, and airway pressures in both groups. Conclusions: IOP changes induced by laparoscopy are realigned after evacuation of pneumoperitoneum. A Trendelenburg tilt however produced significant changes that may require careful patient monitoring during laparoscopic procedures. PMID:28028381

  11. Intraocular pressure, retinal vascular, and visual acuity changes during 48 hours of 10-deg head-down tilt

    NASA Technical Reports Server (NTRS)

    Mader, Thomas H.; Taylor, Gerald R.; Hunter, Norwood; Caputo, Michael; Meehan, Richard T.

    1990-01-01

    Intraocular pressures, retinal vascular diameters, and visual acuities of nine men, were repeatedly measured while the subjects were tilted 10 deg head-down for 48 h and while they were seated before (baseline), and after the tilt. An immediate increase in intraocular pressure, measured by pneumatonometer was recorded when subjects assumed the head-down position, and diurnal variations in intraocular pressures were observed for the 48 h. The initial and final head-down intraocular pressures were not significantly different. However, when subjects resumed the sitting position, intraocular pressures fell below the initial sitting values. Computer image analysis of the retinal vasculature detected a 6 percent and 2 percent reduction in the caliber of arteries and veins, respectively, as compared with sitting baseline values. No changes in visual acuity were documented during the 48 h of head-down tilt. The data suggest that the choroidal blood reservoir increases in volume over 48 h at continuous head-down position with a compensatory decrease in aqueous volume. These findings may explain intraocular pressure changes noted in astronauts during previous space missions and in studies associated with change in body position.

  12. Intraocular Silicone Oil Masquerading as Terson Syndrome

    PubMed Central

    Samavat, Bijan; Mehrian, Payam; Hedayatfar, Alireza

    2016-01-01

    Introduction. Terson syndrome is described as intraocular hemorrhage in association with any type of intracranial hemorrhage and is associated with higher mortality rate and vision loss. Intraocular hemorrhage in Terson syndrome may be diagnosed using computed tomography but there are false positive results. Silicone oil which is widely used for internal tamponade of complicated retinal detachments has high attenuation on computed tomography and hyperintensity on T1-weighted magnetic resonance imaging that can mimic intraocular hemorrhage. This report shows that silicone oil is another origin of false positive results in interpreting CT findings for detecting Terson syndrome. Case Report. A 71-year-old diabetic woman presented with loss of consciousness. Brain computed tomography revealed right cerebellar hemorrhage and ventricular hemorrhage and hyperdensity in vitreous cavity of the left eye that was initially interpreted as vitreous hemorrhage. Terson syndrome was the initial diagnosis but ophthalmoscopic examination and brain MRI showed that the left eye had silicone oil tamponade. Conclusion. Without knowing the history of previous vitreoretinal surgery, CT scan findings of intraocular silicone oil may be interpreted as vitreous hemorrhage. In patients with concomitant intracranial hemorrhage, it can masquerade as Terson syndrome. PMID:27747119

  13. Characterizing intraocular tumors with photoacoustic imaging

    NASA Astrophysics Data System (ADS)

    Xu, Guan; Xue, Yafang; Gursel, Zeynep; Slimani, Naziha; Wang, Xueding; Demirci, Hakan

    2016-03-01

    Intraocular tumors are life-threatening conditions. Long-term mortality from uveal melanoma, which accounts for 80% of primary intraocular tumors, could be as high as 25% depending on the size, ciliary body involvement and extraocular extension. The treatments of intraocular tumors include eye-sparing approaches such as radiotherapy and thermotherapy, and the more aggressive enucleation. The accurate diagnosis of intraocular tumors is thereby critical in the management and follow-up of the patients. The diagnosis of intraocular tumors is usually based on clinical examination with acoustic backscattering based ultrasonography. By analyzing the high frequency fluctuations within the ultrasound (US) signals, microarchitecture information inside the tumor can be characterized. However, US cannot interrogate the histochemical components formulating the microarchitecture. One representative example is the inability of US imaging (and other contemporary imaging modalities as well) in differentiating nevoid and melanoma cells as the two types of cells possesses similar acoustic backscattering properties. Combining optical and US imaging, photoacoustic (PA) measurements encode both the microarchitecture and histochemical component information in biological tissue. This study attempts to characterize ocular tumors by analyzing the high frequency signal components in the multispectral PA images. Ex vivo human eye globes with melanoma and retinoblastoma tumors were scanned using less than 6 mJ per square centimeters laser energy with tunable range of 600-1700 nm. A PA-US parallel imaging system with US probes CL15-7 and L22-14 were used to acquire the high frequency PA signals in real time. Preliminary results show that the proposed method can identify uveal melanoma against retinoblastoma tumors.

  14. Biomechanics of Schlemm's canal endothelium and intraocular pressure reduction.

    PubMed

    Stamer, W Daniel; Braakman, Sietse T; Zhou, Enhua H; Ethier, C Ross; Fredberg, Jeffrey J; Overby, Darryl R; Johnson, Mark

    2015-01-01

    Ocular hypertension in glaucoma develops due to age-related cellular dysfunction in the conventional outflow tract, resulting in increased resistance to aqueous humor outflow. Two cell types, trabecular meshwork (TM) and Schlemm's canal (SC) endothelia, interact in the juxtacanalicular tissue (JCT) region of the conventional outflow tract to regulate outflow resistance. Unlike endothelial cells lining the systemic vasculature, endothelial cells lining the inner wall of SC support a transcellular pressure gradient in the basal to apical direction, thus acting to push the cells off their basal lamina. The resulting biomechanical strain in SC cells is quite large and is likely to be an important determinant of endothelial barrier function, outflow resistance and intraocular pressure. This review summarizes recent work demonstrating how biomechanical properties of SC cells impact glaucoma. SC cells are highly contractile, and such contraction greatly increases cell stiffness. Elevated cell stiffness in glaucoma may reduce the strain experienced by SC cells, decrease the propensity of SC cells to form pores, and thus impair the egress of aqueous humor from the eye. Furthermore, SC cells are sensitive to the stiffness of their local mechanical microenvironment, altering their own cell stiffness and modulating gene expression in response. Significantly, glaucomatous SC cells appear to be hyper-responsive to substrate stiffness. Thus, evidence suggests that targeting the material properties of SC cells will have therapeutic benefits for lowering intraocular pressure in glaucoma.

  15. Elevated Intraocular Pressure Induces Rho GTPase Mediated Contractile Signaling in the Trabecular Meshwork

    PubMed Central

    Pattabiraman, Padmanabhan P; Inoue, Toshihiro; Rao, P. Vasantha

    2015-01-01

    Rho GTPase regulated contractile signaling in the trabecular meshwork (TM) has been shown to modulate aqueous humor (AH) outflow and intraocular pressure (IOP). To explore whether elevated IOP, a major risk factor for primary open angle glaucoma (POAG) influences Rho GTPase signaling in the TM, we recorded AH outflow in enucleated contralateral porcine eyes perfused for 4–5 hours at either 15 mm or 50 mm Hg pressure. After perfusion, TM tissue extracted from perfused eyes was evaluated for the activation status of Rho GTPase, myosin light chain (MLC), myosin phosphatase target substrate 1 (MYPT1), myristoylated alanine-rich C-kinase substrate (MARCKS) and paxillin. Eyes perfused at 50 mm Hg exhibited a significant decrease in AH outflow facility compared with those perfused at 15 mm Hg. Additionally, TM tissue from eyes perfused at 50 mm Hg revealed significantly increased levels of activated RhoA and phosphorylated MLC, MYPT1, MARCKS and paxillin compared to TM tissue derived from eyes perfused at 15 mm Hg. Taken together, these observations indicate that elevated IOP-induced activation of Rho GTPase-dependent contractile signaling in the TM is associated with increased resistance to AH outflow through the trabecular pathway, and demonstrate the sensitivity of Rho GTPase signaling to mechanical force in the AH outflow pathway. PMID:25956210

  16. Long-Term Change in Intraocular Pressure after Extracapsular Cataract Extraction with Posterior Chamber Intraocular Lens Implantation Versus Phacoemulsification with Posterior Chamber Intraocular Lens Implantation in Indians

    PubMed Central

    Pal, Virendra K; Agrawal, Ajai; Suman, Suwarna; Pratap, V B

    2013-01-01

    Purpose: The purpose of the study is to evaluate the long-term changes in intraocular pressure (IOP) after extracapsular cataract extraction (ECCE) with posterior chamber intraocular lens (PCIOL) implantation versus phacoemulsification with PCIOL implantation in otherwise normal cataract patients in India. Materials and Methods: The study was conducted in the Department of Ophthalmology, King George's Medical College, Lucknow between August 2000 and August 2001. One hundred and seventeen eyes of 115 patients were included in the study. 84 patients were randomly selected for ECCE with PCIOL implantation (ECCE group) and 31 patients were selected for phacoemulsification with PCIOL implantation (Phaco group). IOP was measured pre-operatively and post-operatively, from the 1st month to the 12th month. Statistical significance was indicated by P > 0.05. Results: There was a mean fall in IOP of 2.70 mm Hg (19.74%) in the ECCE group and 2.74 mm Hg (20.57%) in the phaco group. The decrease in the mean post-operative IOP from baseline was statistically significant (P > 0.01) at the end of 2 months in both groups. There was no statistically significant difference in post-operative IOP at any visit between groups (P < 0.05, all post-operative visits). After 4th monthpost-operatively, the IOP was mostly stable, but it was significantly lower than the pre-operative IOP. Conclusion: Significant IOP reduction may be expected after cataract surgery with either ECCE or phacoemulsification with IOL implantation. The lowering of IOP became statistically significant at about 2 months post-operatively, but became almost stable after the 4th month. PMID:24339684

  17. The Visual Effects of Intraocular Colored Filters

    PubMed Central

    Hammond, Billy R.

    2012-01-01

    Modern life is associated with a myriad of visual problems, most notably refractive conditions such as myopia. Human ingenuity has addressed such problems using strategies such as spectacle lenses or surgical correction. There are other visual problems, however, that have been present throughout our evolutionary history and are not as easily solved by simply correcting refractive error. These problems include issues like glare disability and discomfort arising from intraocular scatter, photostress with the associated transient loss in vision that arises from short intense light exposures, or the ability to see objects in the distance through a veil of atmospheric haze. One likely biological solution to these more long-standing problems has been the use of colored intraocular filters. Many species, especially diurnal, incorporate chromophores from numerous sources (e.g., often plant pigments called carotenoids) into ocular tissues to improve visual performance outdoors. This review summarizes information on the utility of such filters focusing on chromatic filtering by humans. PMID:24278692

  18. Bio-inspired accommodating fluidic intraocular lens.

    PubMed

    Qiao, Wen; Johnson, Daniel; Tsai, Frank S; Cho, Sung Hwan; Lo, Yu-Hwa

    2009-10-15

    The invention of intraocular lens (IOL), a substitute for crystalline lens, represents a major advancement in cataract surgery. After about sixty years of IOL development, one key remaining problem is its limited accommodation range compared with natural eyes. To overcome this performance limit, we explore bio-inspired fluidic IOL. By mimicking the working principle of natural eyes, a fluidic intraocular lens can achieve an exceedingly large accommodation range. An experiment on fluidic IOL demonstrated a very high tuning range of 12 D. This accommodation range was achieved with a modest amount of force (0.06 N) and equatorial radius change (0.286 mm), in conditions matching well with the characteristics of aged eyes.

  19. Factors affecting intraocular pressure in lions.

    PubMed

    Ofri, Ron; Steinmetz, Andrea; Thielebein, Jens; Horowitz, Igal H; Oechtering, Gerhard; Kass, Philip H

    2008-07-01

    The aim of this study was to conduct a detailed analysis of the relationship between age and intraocular pressure (IOP) in lions. Tonometry was conducted in 33 lions aged 5 days to 80 months. Age was significantly associated with IOP (P<0.005). Mean IOP was 12.8+/- and 23.9+/-4.1 mmHg in lions < or =1 year old and >1 year old, respectively. IOP linearly rose with age during the first 20 months of life, plateaued until approximately 40 months, and then gradually declined (r=0.85). Age-related changes in IOP were highly correlated with ultrasonographic measurements of intraocular dimensions (r > or = 0.72), and may be a determinant factor in developmental ocular growth. The dramatic rise in IOP of young lions is similar to that observed in children, but has not been previously demonstrated in animals. Significant IOP differences between lion sub-species were also demonstrated.

  20. Introduction to the development of intraocular lens

    NASA Astrophysics Data System (ADS)

    Li, Yifan; Peng, Runling; Hu, Shuilan; Wei, Maowei; Chen, Jiabi

    2013-08-01

    In order to cure the cataract disease or injuries in eyes, intraocular lens(IOL) has been studied all the time to replace the crystalline lens in human eyes. Researches on IOL are started early from 19th century, and it develops greatly in the hundreds years after. This article introduces several main kinds of IOLs that appear in the development history of IOL, and raises the double-liquid zoom IOL based on electrowetting, which will be the trend of IOL study.

  1. [A universal laser for intraocular treatment].

    PubMed

    Pomerantzeff, O; Vallat, M; Pankratov, M M; Pflibsen, K P; Schepens, C L

    1988-01-01

    The creation of a single apparatus incorporating the different lasers applicable to intraocular pathology derives from the idea of possessing the means, with one device, of objectively comparing the effects and parameters of various lasers in order to pursue a more precise line of treatment. This has led to our fabrication of the universal intraocular laser. The word universal means the ability of the machine to act on each kind of intraocular tissues with all of the various infrared or other-colored radiations, as well as with different modalities. The unit is transportable. It only requires a source of electric power (110 or 220 V) and includes an independent cooling system. The Nd: YAG laser has selectable operating parameters: pulsed or continuous excitation, Q-switched or mode-locked mode, mirror or fiber optic transmission. It is used also as the basic system of the coloured module. The colour module can provide the three clinically useful radiations: green, red, yellow. The green (532 nm) is obtained by transmission of the I.R. beam brought a birefringent crystal (KTP). Red (650 nm) and yellow (575 nm) come from two incorporated dye lasers excited by the green radiation.

  2. Laboratory analyses of two explanted hydrophobic acrylic intraocular lenses.

    PubMed

    Dai, Yunhai; Huang, Yusen; Liu, Ting; Xie, Lixin

    2014-06-01

    Two three-piece hydrophobic acrylic intraocular lenses (IOLs) were explanted from two patients at 7 and 9 years, respectively, after implantation, because of poor fundus visualisation and/or a clinically significant decrease in visual acuity related to their opacified IOLs. In addition to light microscopy, scanning electron microscopy and energy dispersive X-ray spectroscopy, confocal laser scanning microscopy was used for the first time to observe the explanted IOLs. The clinical aspect seemed to correspond to the phenomenon of surface light scattering, while laboratory analyses showed dense glistenings in the central layer of the IOL optic, which had no change next to the surface. Further studies on these phenomena are needed.

  3. Development of a hydrophobic polymer composition with improved biocompatibility for making foldable intraocular lenses

    NASA Astrophysics Data System (ADS)

    Haldar, R. S.; Chauhan, R.; Kapoor, K.; Niyogi, U. K.

    2014-05-01

    A hydrophobic composition for foldable intraocular lenses was developed by copolymerizing phenyl ethyl acrylate, phenyl ethyl methacrylate and butanediol diacrylate by gamma irradiation. Aqueous solution of heparin, a biocompatibilizer absorbed in hydroxyethyl methacrylate was added to the monomer mixture before irradiation to impart desired level of hydrophilicity and improved biocompatibility to the hydrophobic composition. Ketorolac tromethamine, an anti-inflammatory agent and L-glutathione, an antioxidant were added to the composition as functional additive for exhibiting improved performance while in use. Concentrations of monomers, biocompatibilizer and functional additives were optimized to develop an advanced material for foldable intraocular lenses. Transmittance, refractive index, Abbe number, hardness, tensile strength, flexibility and foldability were studied on the final composition. Scanning electron microscopic study, differential scanning calorimetric analysis, leachability and viscometry confirmed the permanent incorporation of additives into the polymer. Results of haemocompatibility, tissue implantation and cytotoxicity confirm that the biocompatibility of the base polymer was improved by incorporation of heparin.

  4. Evaluating the Biostability of Yellow and Clear Intraocular Lenses with a System Simulating Natural Intraocular Environment

    PubMed Central

    Hayashi, Rijo; Hayashi, Shimmin; Arai, Kiyomi; Yoshida, Shinichirou; Chikuda, Makoto; Machida, Shigeki

    2016-01-01

    Purpose Blue light–filtering intraocular lenses (IOLs) are thought to protect the retina from blue light damage after cataract surgery, and the implantation of yellow-tinted IOLs has been commonly used in cataract surgery. To our knowledge, this is the first investigation measuring the long-term biostability of yellow-tinted IOLs using an in vitro system simulating natural intraocular environment. Methods Six hydrophobic acrylic IOLs, three clear IOLs, and three yellow-tinted IOLs were included in the study. Each yellow-tinted IOL was a matching counterpart of a clear IOL, with the only difference being the lens color. The IOLs were kept in conditions replicating the intraocular environment using a perfusion culture system for 7 months. Resolution, light transmittance rate, and the modulation transfer function (MTF) were measured before and after culturing. Surface roughness of the anterior and posterior surfaces was also measured. Results After culturing for 7 months, there were no changes in the resolution, the light transmittance rate, and MTF. The surface roughness of the anterior and posterior surfaces increased after culturing; however, this increase was clinically insignificant. There were no differences in surface roughness between the clear and yellow-tinted IOLs, either before or after culturing. Conclusions A novel in vitro system replicating intraocular environment was used to investigate the biostability of yellow-tinted IOLs. The surface roughness showed no clinically significant increase after culturing for 7 months. Translational Relevance This system is useful for evaluating the biostability of IOLs. PMID:27933221

  5. Visual performance with accommodating and multifocal intraocular lenses

    PubMed Central

    Lan, Jie; Huang, Yu-Sen; Dai, Yun-Hai; Wu, Xiao-Ming; Sun, Jia-Jun; Xie, Li-Xin

    2017-01-01

    AIM To compare the visual functional outcomes with accommodating and multifocal intraocular lenses (IOLs). METHODS Our retrospective comparative study included 51 patients (60 eyes) received implantation of an accommodating IOL (Tetraflex; 16 patients, 20 eyes), a refractive multifocal IOL (ReZoom; 18 patients, 20 eyes), or a diffractive multifocal IOL (ZMA00; 17 patients, 20 eyes). Subjective refraction, visual acuity, contrast sensitivity (CS), intraocular aberration, and subjective photic phenomena were detected at 3mo after surgery. RESULTS The spherical equivalent in the three groups was -0.38±0.54 D, 0.14±0.56 D, and 0.35±0.41 D, respectively. No statistically significant differences were found in uncorrected and corrected distance visual acuity and uncorrected intermediate visual acuity among the groups (P=0.39). The ReZoom group had significantly better distance-corrected intermediate visual acuity than the ZMA00 group (P=0.003). The ZMA00 group had significantly better near visual acuity than the other groups (P<0.05). Better contrast sensitivity values were observed in the Tetraflex group under most of the spatial frequencies conditions (P=0.025). The total aberration was lowest in the ZMA00 group (P=0.000), and the spherical aberration was highest in the Tetraflex group (P=0.000). The three groups had similar frequency of ghosting and glare, and the Tetraflex group had a low rate of halos (P=0.01). CONCLUSION Both accommodating and multifocal IOLs can successfully restore distance and uncorrected intermediate visual acuities. Tetraflex accommodating IOLs perform better in CS and with less halos of photic phenomena. ReZoom refractive multifocal IOLs have better performance in distance-corrected intermediate visual acuity than ZMA00 diffractive multifocal IOLs, and the latter achieved better near visual acuity and efficiently decreased the optical aberration. PMID:28251082

  6. Comparative Evaluation of Handheld Robot-Aided Intraocular Laser Surgery

    PubMed Central

    Yang, Sungwook; MacLachlan, Robert A.; Martel, Joseph N.; Lobes, Louis A.; Riviere, Cameron N.

    2015-01-01

    This paper presents robot-aided intraocular laser surgery using a handheld robot known as Micron. The micromanipulator incorporated in Micron enables visual servoing of a laser probe, while maintaining a constant distance of the tool tip from the retinal surface. The comparative study was conducted with various control methods for evaluation of robot-aided intraocular laser surgery. PMID:27019653

  7. Circadian rhythm of intraocular pressure in the adult rat.

    PubMed

    Lozano, Diana C; Hartwick, Andrew T E; Twa, Michael D

    2015-05-01

    Ocular hypertension is a risk factor for developing glaucoma, which consists of a group of optic neuropathies characterized by progressive degeneration of retinal ganglion cells and subsequent irreversible vision loss. Our understanding of how intraocular pressure damages the optic nerve is based on clinical measures of intraocular pressure that only gives a partial view of the dynamic pressure load inside the eye. Intraocular pressure varies over the course of the day and the oscillator regulating these daily changes has not yet been conclusively identified. The purpose of this study was to compare and contrast the circadian rhythms of intraocular pressure and body temperature in Brown Norway rats when these animals are housed in standard light-dark and continuous dim light (40-90 lux) conditions. The results from this study show that the temperature rhythm measured in continuous dim light drifted forward relative to external time, indicating that the rhythm was free running and being regulated by an internal biological clock. Also, the results show that there is a persistent, but dampened, circadian rhythm of intraocular pressure in continuous dim light and that the circadian rhythms of temperature and intraocular pressure are not synchronized by the same central oscillator. We conclude that once- or twice-daily clinical measures of intraocular pressure are insufficient to describe intraocular pressure dynamics. Similarly, our results indicate that, in experimental animal models of glaucoma, the common practice of housing animals in constant light does not necessarily eliminate the potential influence of intraocular pressure rhythms on the progression of nerve damage. Future studies should aim to determine whether an oscillator within the eye regulates the rhythm of intraocular pressure and to better characterize the impact of glaucoma on this rhythm.

  8. UV laser ablation of intraocular lenses: SEM and AFM microscopy examination of the biomaterial surface

    NASA Astrophysics Data System (ADS)

    Spyratou, E.; Asproudis, I.; Tsoutsi, D.; Bacharis, C.; Moutsouris, K.; Makropoulou, M.; Serafetinides, A. A.

    2010-02-01

    Several new materials and patterns are studied for the formation and etching of intraocular lenses (IOLs), in order to improve their optical properties, to reduce the diffractive aberrations and to decrease the incidence of posterior capsular opacification. The aim of this study is to investigate the use of UV ( λ = 266 nm) laser pulses to ablate the intraocular lenses materials, and thus to provide an alternative to conventional surface shaping techniques for IOLs fabrication. Ablation experiments were conducted using various polymer substrates of hydrophobic acrylic IOLs and PMMA IOLs. We investigated the ablation efficiency and the morphology of the ablated area by imaging the surface modification with atomic force microscopy (AFM) and scanning electron microscopy (SEM). The morphological appearance of IOL samples reveals the effect of a photochemical and photothermal ablation mechanism.

  9. Bottom-up fabrication of zwitterionic polymer brushes on intraocular lens for improved biocompatibility

    PubMed Central

    Han, Yuemei; Xu, Xu; Tang, Junmei; Shen, Chenghui; Lin, Quankui; Chen, Hao

    2017-01-01

    Intraocular lens (IOL) is an efficient implantable device commonly used for treating cataracts. However, bioadhesion of bacteria or residual lens epithelial cells on the IOL surface after surgery causes postoperative complications, such as endophthalmitis or posterior capsular opacification, and leads to loss of sight again. In the present study, zwitterionic polymer brushes were fabricated on the IOL surface via bottom-up grafting procedure. The attenuated total reflection-Fourier transform infrared and contact angle measurements indicated successful surface modification, as well as excellent hydrophilicity. The coating of hydrophilic zwitterionic polymer effectively decreased the bioadhesion of lens epithelial cells or bacteria. In vivo intraocular implantation results showed good in vivo biocompatibility of zwitterionic IOL and its effectiveness against postoperative complications. PMID:28053528

  10. Evidence for a GPR18 Role in Diurnal Regulation of Intraocular Pressure

    PubMed Central

    Miller, Sally; Leishman, Emma; Oehler, Olivia; Daily, Laura; Murataeva, Natalia; Wager-Miller, Jim; Bradshaw, Heather; Straiker, Alex

    2016-01-01

    Purpose The diurnal cycling of intraocular pressure (IOP) was first described in humans more than a century ago. This cycling is preserved in other species. The physiologic underpinning of this diurnal variation in IOP remains a mystery, even though elevated pressure is indicated in most forms of glaucoma, a common cause of blindness. Once identified, the system that underlies diurnal variation would represent a natural target for therapeutic intervention. Methods Using normotensive mice, we measured the regulation of ocular lipid species by the enzymes fatty acid amide hydrolase (FAAH) and N-arachidonoyl phosphatidylethanolamine phospholipase (NAPE-PLD), mRNA expression of these enzymes, and their functional role in diurnal regulation of IOP. Results We now report that NAPE-PLD and FAAH mice do not exhibit a diurnal cycling of IOP. These enzymes produce and break down acylethanolamines, including the endogenous cannabinoid anandamide. The diurnal lipid profile in mice shows that levels of most N-acyl ethanolamines and, intriguingly, N-arachidonoyl glycine (NAGly), decline at night: NAGly is a metabolite of arachidonoyl ethanolamine and a potent agonist at GPR18 that lowers intraocular pressure. The GPR18 blocker O1918 raises IOP during the day when pressure is low, but not at night. Quantitative PCR analysis shows that FAAH mRNA levels rise with pressure, suggesting that FAAH mediates the changes in pressure. Conclusions Our results support FAAH-dependent NAGly action at GPR18 as the physiologic basis of the diurnal variation of intraocular pressure in mice. PMID:27893106

  11. Natural Killer T Cells Contribute to Neutrophil Recruitment and Ocular Tissue Damage in a Model of Intraocular Tumor Rejection

    PubMed Central

    Ligocki, Ann J.; Niederkorn, Jerry Y.

    2016-01-01

    Purpose Immune privilege of the eye protects the nonregenerative ocular tissues from innate and adaptive immune-mediated inflammation. In the case of intraocular tumors, immune privilege can be arrested to allow for immune-mediated rejection. Activation of innate immune cells can contribute to necrosis of the intraocular tumor and bystander ocular tissue. Identifying the cellular components of the innate immune system that contribute to ocular destruction, but are not needed for tumor rejection, provides insights into the immunopathological sequelae in intraocular tumor rejection. Methods Wild-type (WT), Jα18 knockout (KO) mice lacking type I natural killer T (NKT) cells, and CD1d KO mice lacking all NKT cells, were used to identify the role of type II NKT cells in intraocular tumor rejection immunopathology. Results CD1d KO mice had significantly lowered rates of necrotic eye destruction during tumor rejection compared to WT or Jα18 KO mice. Transcriptome and protein analyses revealed that CD1d KO mice had significantly lower expression of CXCL3 compared to WT or Jα18 KO mice, and this was associated with decreased neutrophil recruitment. The presence of type II NKT cells in WT or Jα18 KO mice led to increased CXCL3, which attracted neutrophils to the intraocular tumor and culminated in destruction of the eye. Conclusions We found that type II NKT cells are critical in initiating a damaging inflammatory antitumor response involving the recruitment of neutrophils that compromises the integrity of the eye. Loss of type II NKT cells or depleting neutrophils allows for a productive intraocular tumor response that converts the rejection phenotype to preserve the eye. PMID:26934137

  12. [Iritis with destabilization of the intraocular pressure due to dislocation of a posterior chamber intraocular lens].

    PubMed

    Handzel, D M

    2012-04-01

    This report concerns the case of a 67-year-old male patient who underwent uncomplicated phacoemulsification with implantation of a posterior chamber intraocular lens (IOL). After an interval of 2 months the patient developed iritis together with an uncontrollable increase in intraocular pressure. After a detailed examination a dislocated haptic of the IOL was identified as the cause of the symptoms. The dislocation had led to uveitis-glaucoma-hyphema syndrome although no hemorrhage was observed. In addition to this complication the haptic had arroded the zonular complex which made implantation of an anterior chamber lens necessary. Although improvements in operating techniques, lens materials and designs have been made uveitis-glaucoma-hyphema syndrome has to be kept in mind. Surgical intervention is the only therapeutic option.

  13. Appetite - decreased

    MedlinePlus

    ... cancer Ovarian cancer Stomach cancer Pancreatic cancer Other causes of decreased appetite include: Chronic liver disease Chronic kidney disease Chronic obstructive pulmonary disease (COPD) Dementia Heart failure ...

  14. Intraocular lens employed for cataract surgery

    NASA Astrophysics Data System (ADS)

    Roszkowska, A. M.; Torrisi, L.

    2014-04-01

    The aim of this paper is to illustrate the techniques of cataract surgery with implantation of intraocular lenses and some physical properties of the used materials. The new technology, coupled with extensive experience and the studied cases, permits to increase the standardization and accuracy of the engravings, by reducing the use and handling of surgical instruments inside the eye. At present it is possible to replace the cataract with crystalline lenses based on biopolymers such as PMMA, silicone, acrylic hydrophilic and hydrophobic acrylic. These materials are increasingly able to replace the natural lens and to ensure the fully functional of the eye. The role of femtosecond lasers in cataract surgery, to assist or replace several aspects of the manual cataract surgery, are discussed.

  15. Mechanical properties of intra-ocular lenses

    NASA Astrophysics Data System (ADS)

    Ehrmann, Klaus; Kim, Eon; Parel, Jean-Marie

    2008-02-01

    Cataract surgery usually involves the replacement of the natural crystalline lens with a rigid or foldable intraocular lens to restore clear vision for the patient. While great efforts have been placed on optimising the shape and optical characteristics of IOLs, little is know about the mechanical properties of these devices and how they interact with the capsular bag once implanted. Mechanical properties measurements were performed on 8 of the most commonly implanted IOLs using a custom build micro tensometer. Measurement data will be presented for the stiffness of the haptic elements, the buckling resistance of foldable IOLs, the dynamic behaviour of the different lens materials and the axial compressibility. The biggest difference between the lens types was found between one-piece and 3-piece lenses with respect to the flexibility of the haptic elements

  16. Intraocular camera for retinal prostheses: Refractive and diffractive lens systems

    NASA Astrophysics Data System (ADS)

    Hauer, Michelle Christine

    The focus of this thesis is on the design and analysis of refractive, diffractive, and hybrid refractive/diffractive lens systems for a miniaturized camera that can be surgically implanted in the crystalline lens sac and is designed to work in conjunction with current and future generation retinal prostheses. The development of such an intraocular camera (IOC) would eliminate the need for an external head-mounted or eyeglass-mounted camera. Placing the camera inside the eye would allow subjects to use their natural eye movements for foveation (attention) instead of more cumbersome head tracking, would notably aid in personal navigation and mobility, and would also be significantly more psychologically appealing from the standpoint of personal appearances. The capability for accommodation with no moving parts or feedback control is incorporated by employing camera designs that exhibit nearly infinite depth of field. Such an ultracompact optical imaging system requires a unique combination of refractive and diffractive optical elements and relaxed system constraints derived from human psychophysics. This configuration necessitates an extremely compact, short focal-length lens system with an f-number close to unity. Initially, these constraints appear highly aggressive from an optical design perspective. However, after careful analysis of the unique imaging requirements of a camera intended to work in conjunction with the relatively low pixellation levels of a retinal microstimulator array, it becomes clear that such a design is not only feasible, but could possibly be implemented with a single lens system.

  17. Continual monitoring of intraocular pressure: effect of central venous pressure, respiration, and eye movements on continual recordings of intraocular pressure in the rabbit, dog, and man.

    PubMed Central

    Cooper, R. L.; Beale, D. G.; Constable, I. J.; Grose, G. C.

    1979-01-01

    A new method has been devised for continual monitoring of intraocular pressure by radiotelemetry. The use of this instrument for monitoring intraocular pressure by a variety of ophthalmic conditions is described. Images PMID:526459

  18. Computational modeling of intraocular gas dynamics

    NASA Astrophysics Data System (ADS)

    Noohi, P.; Abdekhodaie, M. J.; Cheng, Y. L.

    2015-12-01

    The purpose of this study was to develop a computational model to simulate the dynamics of intraocular gas behavior in pneumatic retinopexy (PR) procedure. The presented model predicted intraocular gas volume at any time and determined the tolerance angle within which a patient can maneuver and still gas completely covers the tear(s). Computational fluid dynamics calculations were conducted to describe PR procedure. The geometrical model was constructed based on the rabbit and human eye dimensions. SF6 in the form of pure and diluted with air was considered as the injected gas. The presented results indicated that the composition of the injected gas affected the gas absorption rate and gas volume. After injection of pure SF6, the bubble expanded to 2.3 times of its initial volume during the first 23 h, but when diluted SF6 was used, no significant expansion was observed. Also, head positioning for the treatment of retinal tear influenced the rate of gas absorption. Moreover, the determined tolerance angle depended on the bubble and tear size. More bubble expansion and smaller retinal tear caused greater tolerance angle. For example, after 23 h, for the tear size of 2 mm the tolerance angle of using pure SF6 is 1.4 times more than that of using diluted SF6 with 80% air. Composition of the injected gas and conditions of the tear in PR may dramatically affect the gas absorption rate and gas volume. Quantifying these effects helps to predict the tolerance angle and improve treatment efficiency.

  19. Computational modeling of intraocular gas dynamics.

    PubMed

    Noohi, P; Abdekhodaie, M J; Cheng, Y L

    2015-12-18

    The purpose of this study was to develop a computational model to simulate the dynamics of intraocular gas behavior in pneumatic retinopexy (PR) procedure. The presented model predicted intraocular gas volume at any time and determined the tolerance angle within which a patient can maneuver and still gas completely covers the tear(s). Computational fluid dynamics calculations were conducted to describe PR procedure. The geometrical model was constructed based on the rabbit and human eye dimensions. SF6 in the form of pure and diluted with air was considered as the injected gas. The presented results indicated that the composition of the injected gas affected the gas absorption rate and gas volume. After injection of pure SF6, the bubble expanded to 2.3 times of its initial volume during the first 23 h, but when diluted SF6 was used, no significant expansion was observed. Also, head positioning for the treatment of retinal tear influenced the rate of gas absorption. Moreover, the determined tolerance angle depended on the bubble and tear size. More bubble expansion and smaller retinal tear caused greater tolerance angle. For example, after 23 h, for the tear size of 2 mm the tolerance angle of using pure SF6 is 1.4 times more than that of using diluted SF6 with 80% air. Composition of the injected gas and conditions of the tear in PR may dramatically affect the gas absorption rate and gas volume. Quantifying these effects helps to predict the tolerance angle and improve treatment efficiency.

  20. INTRAOCULAR SILICONE BALL IMPLANTATION AFTER EVISCERATION IN A SLOW LORIS (NYCTICEBUS COUCANG).

    PubMed

    Kim, Jury; Kim, Young-Jun; Ji, Dong-Beom; Kim, Min-Su

    2016-06-01

    A slow loris, Nycticebus coucang , was brought to Ji Dong Beom Animal Hospital from the National Institute of Ecology due to globe enlargement and frequent blepharospasm of the right eye. Ophthalmic diagnoses included glaucoma with posterior lens luxation and cataract. Because this animal was on exhibition at the National Institute of Ecology, preservation of the eyeball by intraocular silicone implantation following evisceration rather than enucleation was selected. Before the surgery, examination of the normal left eye was performed using Retcam and spectral domain optical coherence tomography. Three months later, the globe size was almost the same as the left eye; however, corneal edema remained.

  1. [Intraocular hydrodynamics failure as a part of age cataract etiopathogenesis].

    PubMed

    Ignat'ev, S G; Shilkin, G A; Iartseva, N S; Ignat'eva, S G; Al'-Dandan, I Kh

    2011-01-01

    59 (105 eyes) patients with initial, premature and mature cataract are studied. Besides 14 patients (19 eyes) 1-2 years after cataract phacoemulsification with IOL implantation were examined. All patients underwent routine ophthalmological examination and tonography. Average indexes of intraocular hydrodynamics coefficients differed from normal rates: in initial and premature cataract F- coefficient was lower by 34% compared to normal, in mature cataract it was higher by 8,9% than upper limit of normal, in pseudophakia by 86,8% lower. In all groups with cataract patients disbalance of intraocular hydrodynamics was revealed in more than 70% cases, and in pseudophakia group it was found in 100%. Disbalance of intraocular hydrodynamics in cataract confirms hypothesis that intraocular hydrodynamics failure is an important part of cataract etiopathogenesis.

  2. [Intraocular lens implantation in developmental lens disorders in children].

    PubMed

    Kanigowska, Krystyna; Grałek, Mirosława; Kepa, Beata; Chipczyńska, Barbara

    2009-01-01

    The pediatric cataract surgery in eyes with developmental disorders, stay with still considerable challenge. At children, the lasting vision development extorts necessity quick settlement of refraction defect formed after operation. The intraocular lens old boy with cataract in microspherophakia and 12 years old boy with cataract in lens with coloboma. One-piece flexible and rigid PMMA intraocular lens was placed with success at posterior chamber without scleral fixations and without using capsular tension ring in this cases. After 3 years of observation there were no decentration or dislocation of intraocular lens in both children. Authors concluded that in some cases posterior chamber intraocular lens implantation despite defective zonular or capsular support, can make up the effective method of surgical treatment without risk of early dislocation.

  3. Postprandial Glucose as a Risk Factor for Elevated Intraocular Pressure

    PubMed Central

    Wu, Chen-Jung; Fang, Wen-Hui; Kao, Tung-Wei; Chen, Ying-Jen; Liaw, Fang-Yih; Chang, Yaw-Wen; Wang, Gia-Chi; Peng, Tao-Chun; Chen, Wei-Liang

    2016-01-01

    The aim of this study was to investigate the association between postprandial glucose and intraocular pressure in a relatively healthy population. We examined 1,439 adults getting a health check-up in a health promotion center at Tri-Service General Hospital (TSGH) in Taiwan between 2012 and 2013. All participants underwent examinations to measure metabolic variables and intraocular pressure. Multiple linear regression analyses were performed to assess the relationship between postprandial glucose and intraocular pressure. The levels of postprandial glucose were divided into quartiles with subjects in the lowest quartile being regarded as the reference group to perform quartile-based analysis. Covariate adjustment was designed for three models for further analysis. Subjects with higher quartiles of postprandial glucose level had a higher systolic blood pressure, a greater waist circumference and an elevated fasting glucose level (all p < 0.001). The β coefficient with adjusted covariates showed a significant positive association between postprandial glucose and intraocular pressure. The trends of intraocular pressure across increasing quartiles of postprandial glucose were statistically significant (all p for trend < 0.001). Thus, higher levels of postprandial glucose positively correlated with elevated intraocular pressure. PMID:27977733

  4. Long-term effects of mild exercise on intraocular pressure in athletes and sedentary subjects.

    PubMed

    Dane, Senol; Koçer, Ibrahim; Demirel, Havva; Uçok, Kağan; Tan, Uner

    2006-10-01

    The long-term effects of acute submaximal exercise on intraocular pressures (IOPs) of right-and left-eyes and recovery times to basement levels of IOP in postexercise periods in sedentary and physically fit subjects were investigated. Twenty-five sedentary and 24 physically fit subjects, ranging in age 17 to 22 years, participated. Intraocular pressures were measured by a pneumotonometer. Measurements were taken in the morning at about nine (at rest) and immediately, 30 min and 2 h after acute submaximal exercise. In sedentary subjects, IOPs of both right- and left-eyes decreased immediate after exercise, but, these decreases in both eyes continued 30 min and 2 h after exercise. In physically fit subjects, IOPs of both right- and left-eyes increased immediate after exercise, but decreased after 30 min exercise compared to basement levels, and this decrease continued 2 h after exercise. Acute submaximal exercise decreased IOPs of right and left eyes over a period 2 h in sedentary and physically fit subjects. IOP reducing after exercise was different between right- and left-eyes in sedentary subjects. These results suggest that exercise can be used in ocular hypertension treatment.

  5. Sonothrombolysis for intraocular fibrin formation in an animal model.

    PubMed

    Yamashita, Toshifumi; Ohtsuka, Hiroki; Arimura, Noboru; Sonoda, Shozo; Kato, Chihiro; Ushimaru, Kaneo; Hara, Naoko; Tachibana, Katsuro; Sakamoto, Taiji

    2009-11-01

    Vascular diseases such as diabetic retinopathy or retinal arterial occlusion are always associated with retinal and/or choroidal vasculopathy and intravascular thrombosis is commonly found. The ultrasound (US) therapy is a recently developed technique to accelerate fibrinolysis and it is being applied to some clinical fields. The present study was to observe the effects of extraocular US exposure on intraocular fibrin, which is a deteriorating factor in various ocular diseases. Tubes containing human blood (2 mL) in the following groups were irradiated with US; US alone, US with tissue plasminogen activator (tPA), tPA alone, and saline (control). Fibrinolysis was quantified by measuring D-dimer after 2h. In rat eyes, intracameral fibrin (fibrin formation in the anterior chamber of the eye) was induced by YAG-laser-induced iris bleeding. Then, eyes in the following groups were irradiated with US; US alone, subconjunctival tPA alone, US and subconjunctival tPA, control. Intracameral fibrin was scored on day 3 (3+ maximum to 0). The temperatures of rat eyes were measured by infrared thermography. Histologic evaluation was also performed. D-dimer was increased by US with statistical significance (p <0.05) or tPA (p <0.01). D-dimer in US with tPA group was significantly higher than either US alone or tPA alone group (p <0.01). In rat eyes, the average intracameral fibrin score on day 3 was 1.4 in control group and 1.2 in subconjunctival tPA alone group; however, it decreased significantly in the US alone group (0.75; p <0.05, vs. control), US and subconjunctival tPA group (0.71; p <0.01, vs. control). The temperature was less than 34 degrees C after US exposure. No histologic damage was observed. US irradiation from outside accelerated intracameral fibrinolysis without causing apparent tissue damage. This noninvasive method might have therapeutic value for intraocular fibrin.

  6. Ethics on Exhibit

    ERIC Educational Resources Information Center

    Vick, Randy M.

    2011-01-01

    This article discusses ethical questions raised by an exhibition of work by an artist with a history of mental illness and the exhibition's relevance to art therapy and “outsider art” discourse on the subject. Considerations for how such an exhibit could be handled had the circumstances included an art therapist and art therapy client are…

  7. Effects of flunixin meglumine and dexamethasone on aqueous protein values after intraocular surgery in the dog.

    PubMed

    Krohne, S D; Vestre, W A

    1987-03-01

    Effects of flunixin meglumine and/or dexamethasone on aqueous protein concentrations were evaluated in dogs during and after intraocular surgery. Flunixin meglumine plus dexamethasone had the greatest inhibitory effect on postoperative aqueous protein increases with 64.2% inhibition over base-line aqueous protein values 24 hours after surgery. Dexamethasone alone had a 45.6% inhibition and flunixin meglumine alone had a 22.4% inhibition. Treatment with these drugs separately or in combination had a marked effect in decreasing postoperative inflammation.

  8. Use of Verisyse iris-supported phakic intraocular lens for myopia in keratoconic patients.

    PubMed

    Moshirfar, Majid; Grégoire, François J; Mirzaian, Garen; Whitehead, George F; Kang, Paul C

    2006-07-01

    We report 2 patients with stable keratoconus and high myopia who benefited from implantation of an iris-supported phakic intraocular lens (Verisyse, AMO) for correction of their refractive error. Both patients had a postoperative uncorrected visual acuity of 20/40. Endothelial cell density showed at most a 4% decrease, and no evidence of keratoconus progression was witnessed. The use of the Verisyse lens may be beneficial for certain keratoconic patients as an alternative step between rigid gas-permeable lenses and penetrating keratoplasty.

  9. Ocular Biocompatibility of Nitinol Intraocular Clips

    PubMed Central

    Velez-Montoya, Raul; Erlanger, Michael

    2012-01-01

    Purpose. To evaluate the tolerance and biocompatibility of a preformed nitinol intraocular clip in an animal model after anterior segment surgery. Methods. Yucatan mini-pigs were used. A 30-gauge prototype injector was used to attach a shape memory nitinol clip to the iris of five pigs. Another five eyes received conventional polypropylene suture with a modified Seipser slip knot. The authors compared the surgical time of each technique. All eyes underwent standard full-field electroretinogram at baseline and 8 weeks after surgery. The animals were euthanized and eyes collected for histologic analysis after 70 days (10 weeks) postsurgery. The corneal thickness, corneal endothelial cell counts, specular microscopy parameters, retina cell counts, and electroretinogram parameters were compared between the groups. A two sample t-test for means and a P value of 0.05 were use for assessing statistical differences between measurements. Results. The injection of the nitinol clip was 15 times faster than conventional suturing. There were no statistical differences between the groups for corneal thickness, endothelial cell counts, specular microscopy parameters, retina cell counts, and electroretinogram measurements. Conclusions. The nitinol clip prototype is well tolerated and showed no evidence of toxicity in the short-term. The injectable delivery system was faster and technically less challenging than conventional suture techniques. PMID:22064995

  10. Surface characterization of polymer-drug modified vascular stents and intraocular lenses

    NASA Astrophysics Data System (ADS)

    Elachchabi, Amin

    Two of the most important medical devices in clinical use today are endoluminal stents and intraocular lenses (IOLs). In both devices, surface and interfacial properties are of basic importance in the development and clinical performance of these devices. Drug eluting stents have revolutionized the world of interventional cardiology. Research reported here was devoted to the design and development of new drug eluting stents wherein the metallic backbone is completely embedded in a polymeric matrix used also as a drug reservoir. This design, using silicone-drug compositions can lead to higher drug payloads, less tissue damage during angioplasty balloon/stent expansion, and the novel capability of delivering multiple drugs. The adhesion of the polymeric coating to the metallic stent is essential and has not been adequately reported previously. The adhesion of polydimethylsiloxane (PDMS) coatings to a stainless steel stent substrate was shown to be enhanced by the application of mixtures of tetra-n-propyl silicate, tetrabutyltitanate, tetra-2-methoxyethoxysilane, and 3-(trimethoxysilyl)propyl methacrylate coupling agents. Additionally, the effect of drug loading on the stress/strain properties of the polymeric coating is of basic importance. The tensile strength and percent elongation of dexamethasone loaded PDMS films was shown to remain satisfactory for stent coatings at low concentrations (less than 1%) but decreased as the concentrations of dexamethasone in PDMS was increased to 5%. The release of multiple therapeutic agents from PDMS coatings to reduce in-stent restenosis has not been previously reported. The release profile of Paclitaxel, dexamethasone 21-acetate, and their combination from PDMS coatings was studied using high precision liquid chromatography (HPLC). Although dexamethasone release was reduced by paclitaxel, paclitaxel release was unaffected by combination with dexamethasone. Paclitaxel release from the polymeric matrices was shown to inhibit

  11. Relationship between homocysteine and intraocular pressure in men and women

    PubMed Central

    Leibovitzh, Haim; Cohen, Eytan; levi, Amos; Kramer, Michal; Shochat, Tzippy; Goldberg, Elad; Krause, Ilan

    2016-01-01

    Abstract The relationship between homocysteine levels and glaucoma has been questioned in previous studies without conclusive results. In the current study, we assessed the relationship between homocysteine levels and intraocular pressure which is one of the main factors in the development of glaucoma in men and women. A retrospective cross-sectional analysis of a database from a screening center in Israel which assessed 11,850 subjects, within an age range 20 to 80 years. The relationship between homocysteine and intraocular pressure has been investigated by comparing intraocular pressure in subjects with elevated and normal homocysteine and by comparing homocysteine levels in subjects with elevated and normal intraocular pressure. In addition, we compared the levels of homocysteine in subjects with and without a confirmed diagnosis of glaucoma. The mean IOP (±SD) in subjects with normal homocysteine levels(≤15 μmol/L) was 13.2 ± 2.3 mm Hg and 13.4 ± 2.4 mm Hg in those with high homocysteine levels (>15 μmol/L) (P < 0.008, 95% confidence interval [CI] 0.3–0.09).Nonetheless, after multivariate adjustment for age, gender, vitamin B12, and folic acid statistical significance was no longer demonstrated (P = 0.37). Mean homocysteine levels (±SD) in subjects with normal intraocular pressure of ≤ 21 mm Hg was 11.7 ± 5.5 μmol/L and 12.09 ± 3.43 μmol/L in those with elevated intraocular pressure (P = 0.4, 95%CI 1.1–1.8). Mean homocysteine levels (±SD) in subjects with glaucoma were 11.2 ± 3.5 μmol/L compared to 11.7 ± 5.5 μmol/L in subjects without glaucoma and normal intraocular pressure ≤ 21 mm Hg (P = 0.4, 95% CI 1.2–2.1). The current study displays no clinical correlation between the homocysteine level and the intraocular pressure. Homocysteine may not be used as a predictive parameter to recognize those subjects prone to develop elevated intraocular pressure. PMID:27661027

  12. Ultrasound biomicroscopy in pupillary block glaucoma secondary to ophthalmic viscosurgical device remnants in the posterior chamber after anterior chamber phakic intraocular lens implantation.

    PubMed

    Sun, Chuan-Bin; Liu, Zhe; Yao, Ke

    2010-12-01

    A 25-year-old woman developed pupillary block glaucoma in the right eye after implantation of an angle-supported phakic intraocular lens despite a preexisting moderate-sized iridectomy. Ultrasound biomicroscopy (UBM) showed ophthalmic viscosurgical device retention in the posterior chamber and a full-thickness, patent-appearing iridectomy at 12 o'clock. The intraocular pressure gradually decreased to normal after a neodymium:YAG laser iridotomy was performed midperipherally at 9 o'clock. To our knowledge, this is the first report of UBM findings of this complication.

  13. Primary Phacoemulsification and Intraocular Lens Implantation for Acute Primary Angle-Closure

    PubMed Central

    Su, Wei-Wen; Chen, Phil Yeong-Fung; Hsiao, Ching-Hsi; Chen, Henry Shen-Lih

    2011-01-01

    Background To investigate the effect of primary phacoemulsification on intraocular pressure (IOP) in patients with acute primary angle-closure (PAC) and coexisting cataract. Methodology Sixteen eyes of 14 patients with acute PAC received phacoemulsification and intraocular lens implantation as initial management for medically uncontrolled IOP in a retrospective chart review. The effects on IOP, vision, anterior chamber depth (ACD), and number of antiglaucoma medications were evaluated. Principal Findings The postoperative IOP was reduced in 16 eyes (100%). The mean ± standard deviation preoperative IOP was 48.81±16.83 mm Hg, which decreased postoperatively to 16.46±10.67 mm Hg at 1 day, 9.43±3.03 mm Hg at 1 week, 9.49±2.14 mm Hg at 2 weeks, 10.78±3.56 mm Hg at 1 month, and 10.70±2.80 mm Hg at 3 months (p<0.001). The mean number of antiglaucoma medications decreased from 3.56±1.14 to 0.13±0.34 (p<0.001). The average preoperative ACD was 2.08±0.35 mm, which increased to 3.59±0.33 mm after surgery (p<0.001). Visual acuity (converted into logarithm of the minimum angle of resolution [logMAR]) improved from 1.14±0.71 to 0.73±0.53 (p = 0.001). Conclusions Primary phacoemulsification plus intraocular lens implantation lowered IOP, reduced the use of antiglaucoma medications, and improved vision in patients with acute PAC. This is a safe and effective method of IOP control and can be considered a first treatment option in managing patients with acute PAC and coexisting cataract. PMID:21629644

  14. An Exhibit for Touching.

    ERIC Educational Resources Information Center

    Hunt, Susan

    1979-01-01

    An exhibit designed for visually handicapped persons presented by the Kalamazoo (Michigan) Institute of Art included bronze sculptures and oil paintings from the institute's permanent collection. (CL)

  15. Optic nerve head and intraocular pressure in the guinea pig eye.

    PubMed

    Ostrin, Lisa A; Wildsoet, Christine F

    2016-05-01

    The guinea pig is becoming an increasingly popular model for studying human myopia, which carries an increased risk of glaucoma. As a step towards understanding this association, this study sought to characterize the normal, developmental intraocular pressure (IOP) profiles, as well as the anatomy of the optic nerve head (ONH) and adjacent sclera of young guinea pigs. IOP was tracked in pigmented guinea pigs up to 3 months of age. One guinea pig was imaged in vivo with OCT and one with a fundus camera. The eyes of pigmented and albino guinea pigs (ages 2 months) were enucleated and sections from the posterior segment, including the ONH and surrounding sclera, processed for histological analyses - either hematoxylin and eosin (H&E) staining of paraffin embedded, sectioned tissue (n = 1), or cryostat sectioned tissue, processed for immunohistochemistry (n = 3), using primary antibodies against collagen types I-V, elastin, fibronectin and glial fibrillary acidic protein (GFAP). Transmission and scanning electron microscopy (TEM, SEM) studies of ONHs were also undertaken (n = 2 & 5 respectively). Mean IOPs ranged from 17.33 to 22.7 mmHg, increasing slightly across the age range studied, and the IOPs of individual animals also exhibited diurnal variations, peaking in the early morning (mean of 25.8, mmHg, ∼9 am), and decreasing across the day. H&E-stained sections showed retinal ganglion cell axons organized into fascicles in the prelaminar and laminar region of the ONHs, with immunostained sections revealing collagen types I, III, IV and V, as well as elastin, GFAP and fibronectin in the ONHs. SEM revealed a well-defined lamina cribrosa (LC), with radially-oriented collagen beams. TEM revealed collagen fibrils surrounding non-myelinated nerve fiber bundles in the LC region, with myelination and decreased collagen posterior to the LC. The adjacent sclera comprised mainly crimped collagen fibers in a crisscross arrangement. Both the sclera and LC were

  16. A Teaching Aids Exhibition.

    ERIC Educational Resources Information Center

    Mahanja, Salah

    1985-01-01

    Describes an exhibition for the benefit of teachers of English in Arab Primary Schools, which was prepared by third-year students at the Teachers College for Arab Teachers. The exhibition included games, songs, audiovisual aids, crossword puzzles, vocabulary, spelling booklets, preposition aids, and worksheet and lesson planning aids. (SED)

  17. New trends in intraocular lens imaging

    NASA Astrophysics Data System (ADS)

    Millán, María S.; Alba-Bueno, Francisco; Vega, Fidel

    2011-08-01

    As a result of modern technological advances, cataract surgery can be seen as not only a rehabilitative operation, but a customized procedure to compensate for important sources of image degradation in the visual system of a patient, such as defocus and some aberrations. With the development of new materials, instruments and surgical techniques in ophthalmology, great progress has been achieved in the imaging capability of a pseudophakic eye implanted with an intraocular lens (IOL). From the very beginning, optical design has played an essential role in this progress. New IOL designs need, on the one hand, theoretical eye models able to predict optical imaging performance and on the other hand, testing methods, verification through in vitro and in vivo measurements, and clinical validation. The implant of an IOL requires a precise biometry of the eye, a prior calculation from physiological data, and an accurate position inside the eye. Otherwise, the effects of IOL calculation errors or misplacements degrade the image very quickly. The incorporation of wavefront aberrometry into clinical ophthalmology practice has motivated new designs of IOLs to compensate for high order aberrations in some extent. Thus, for instance, IOLs with an aspheric design have the potential to improve optical performance and contrast sensitivity by reducing the positive spherical aberration of human cornea. Monofocal IOLs cause a complete loss of accommodation that requires further correction for either distance or near vision. Multifocal IOLs address this limitation using the principle of simultaneous vision. Some multifocal IOLs include a diffractive zone that covers the aperture in part or totally. Reduced image contrast and undesired visual phenomena, such as halos and glare, have been associated to the performance of multifocal IOLs. Based on a different principle, accommodating IOLs rely on the effort of the ciliary body to increase the effective power of the optical system of the

  18. Molecular pathology of primary intraocular lymphoma.

    PubMed Central

    Chan, Chi-Chao

    2003-01-01

    PURPOSE: To evaluate immunoglobulin heavy chain (IgH) gene rearrangements, cytokines and chemokines, and infectious agents in primary intraocular B-cell lymphoma (PIOL) cells, in order to better diagnose and understand PIOL. METHODS: We studied ocular specimens from 57 patients with PIOL at the National Eye Institute from 1991 to 2001. Specimens were analyzed for IgH gene rearrangements using microdissection and polymerase chain reaction (PCR). We measured vitreal interleukin (IL)-10 and IL-6 levels by enzyme-linked immunosorbent assay. IL-10 mRNA was studied in PIOL cells using microdissection and reverse transcribed (RT)-PCR. Chemokine and chemokine receptor expression was examined by using immunohistochemistry. Infectious DNA of human herpetic virus-8 (HHV-8), Epstein-Bar virus (EBV), and Toxoplasma gondii was detected by using microdissection and PCR and was confirmed with Southern blot hybridization. RESULTS: IgH rearrangement(s) were demonstrated in all 50 tested cases. Cytokine levels were measured in the vitreous of 39 patients. Thirty-one had measurable cytokine levels: 24 of 31 had elevation of IL-10 relative to that of IL-6, and, in contrast, only 7 of 31 had elevation of IL-6 relative to IL-10. IL-10 mRNA was abundant in lymphoma cells of 6 examined cases. Lymphoma cells expressed chemokine receptors of CXCR4 and CXCR5 in three tested cases. HHV-8 DNA was found in 6 of 32 cases (18.8%), EBV DNA in 2 of 21 (9.5%), and T gondii DNA in 2 of 16 (12.5%). CONCLUSIONS: Molecular analyses detecting IgH rearrangements and vitreal levels of IL-10 and IL-6 are useful adjuncts for PIOL diagnosis. A role for specific infectious agents is hypothesized in the pathogenesis of some cases of PIOL. B-cell chemokine is likely involved in attracting PIOL cells into the eye. PMID:14971583

  19. Retropupillary iris claw intraocular lens implantation in aphakia for dislocated intraocular lens

    PubMed Central

    Faria, Mun Yueh; Ferreira, Nuno Pinto; Pinto, Joana Medeiros; Sousa, David Cordeiro; Leal, Ines; Neto, Eliana; Marques-Neves, Carlos

    2016-01-01

    Background Nowadays, dislocated intraocular lenses (IOLs) and inadequate capsular support are becoming a challenge for every ophthalmic surgeon. Explantation of dislocated IOL and iris claw IOL (ICIOL) are the techniques that have been used in our ophthalmic department. The aim of this study is to report our technique for retropupillar ICIOL. Methods This study is a retrospective case series. A total of 105 eyes with dislocated IOL from the patients at the Department of Ophthalmology in Santa Maria Hospital, a tertiary reference hospital in Lisbon, Portugal, from January 2012 until January 2016, had been analyzed. Of these 105 eyes, 66 eyes had dislocated one-piece IOL and 39 eyes had dislocated three-piece IOL. The latter underwent iris suture of the same IOL and were excluded from this study. The remaining 66 eyes with dislocated one-piece IOL underwent pars plana vitrectomy, that is, explantation of dislocated IOL through corneal incision and an implantation of retropupillary ICIOL. Operative data and postoperative outcomes included best corrected visual acuity, IOL position, intraocular pressure, pigment dispersion, clinical signs of endothelial cell loss, and anterior chamber depth. Results The mean follow-up was 23 months (range: 6–48 months). The mean preoperative best corrected visual acuity was 1.260±0.771 logMAR, and postoperative best corrected visual acuity was 0.352±0.400 logMAR units. Mean vision gain was 0.909 logMar units. The patients had the following complications: 1) retinal detachment was found in one patient, 2) corneal edema was found in three patients, 3) high intraocular pressure was observed in twelve patients, 4) subluxation of the IOL was observed in one patient, and 5) macular edema was found in three eyes. Conclusion The results demonstrate that retropupillary ICIOL is an easy and effective method for the correction of aphakia in patients not receiving capsule support. The safety of this procedure must be interpreted in the context

  20. Communicating Science through Exhibitions

    NASA Astrophysics Data System (ADS)

    Dusenbery, P.; Harold, J.; Morrow, C.

    It is critically important for the public to better understand the scientific process. Museum exhibitions are an important part of informal science education that can effectively reach public audiences as well as school groups. They provide an important gateway for the public to learn about compelling scientific endeavors. There are many ways for scientists to help develop science exhibitions. The Space Science Institute (SSI) is a national leader in producing traveling science exhibitions and their associated educational programming (i.e. interactive websites, educator workshops, public talks, instructional materials). Two of its exhibitions, Space Weather Center and MarsQuest, are currently on tour. Another exhibition, Alien Earths, is in development. The Space Weather Center was developed in partnership with various research missions at NASA's Goddard Space Flight Center. MarsQuest is a 5000 square-foot traveling exhibition. The exhibit's second 3-year tour began this January at the Detroit Science Center. It is enabling millions of Americans to share in the excitement of the scientific exploration of Mars and to learn more about their own planet in the process. The 3,000 square-foot traveling exhibition, called Alien Earths, will bring origins-related research and discoveries to students and the American public. Alien Earths has four interrelated exhibit areas: Our Place in Space, Star Birth, PlanetQuest, and Search for Life. Exhibit visitors will explore the awesome events surrounding the birth of stars and planets; they will join scientists in the hunt for planets outside our solar system including those that may be in ``habitable zones'' around other stars; and finally they will be able to learn about how scientists are looking for signs of life beyond Earth. Besides the exhibits, SSI is also developing interactive web sites based on exhibit themes. New technologies are transforming the Web from a static medium to an interactive environment with tremendous

  1. An experimental approach to the study of intraocular Toxocara canis.

    PubMed Central

    Luxenberg, M N

    1979-01-01

    An experimental study of nematode endophthalmitis due to T canis and review of the literature has been presented. Six owl monkeys were infected either by nasogastric tube using embryonated T canis eggs or by carotid or intravitreal injection of second stage larvae. The clinical manifestations, especially ocular, were observed and various diagnostic tests performed. Only minimal or no intraocular changes were seen after systemic infection but significant abnormalities such as retinal hemorrhages and venous dilation were noted after intravitreal infection. Motile larvae were observed in the lenses of three eyes and in the vitreous of five eyes and, probably a sixth, after intravitreal injection. The intensity and timing of the intraocular reaction seemed to correlate with the infecting dose and apparent disappearance of larvae from the eye. Pathologic confirmation of larvae in the lens was obtained in one eye. A marked inflammatory reaction occurred in eyes receiving intraocular infection but none was seen in eyes with only systemic infectin. Various laboratory and serologic studies were performed, including the ELISA test, which were used to evaluate systemic as well as intraocular responses to infection with T canis. The two monkeys infected by nasogastric tube gave a positive ELISA response in the serum but intraocular fluids gave a negative response in all monkeys including those infected syst:mically and/or intraocularly. Problems in the understanding of clinical aspects of the disease, laboratory diagnosis and treatment are discussed. The need for future experimental studies is emphasized. Images FIGURE 1 A FIGURE 1 B FIGURE 1 C FIGURE 2 A FIGURE 2 B FIGURE 2 C FIGURE 2 D FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 A FIGURE 6 B FIGURE 7 FIGURE 8 FIGURE 9 A FIGURE 9 B FIGURE 10 FIGURE 11 FIGURE 12 FIGURE 13 FIGURE 14 PMID:120993

  2. Visual performance after the implantation of a new trifocal intraocular lens

    PubMed Central

    Vryghem, Jérôme C; Heireman, Steven

    2013-01-01

    Purpose To evaluate the subjective and objective visual results after the implantation of a new trifocal diffractive intraocular lens. Methods A new trifocal diffractive intraocular lens was designed combining two superimposed diffractive profiles: one with +1.75 diopters (D) addition for intermediate vision and the other with +3.50 D addition for near vision. Fifty eyes of 25 patients that were operated on by one surgeon are included in this study. The uncorrected and best distance-corrected monocular and binocular, near, intermediate, and distance visual acuities, contrast sensitivity, and defocus curves were measured 6 months postoperatively. In addition to the standard clinical follow-up, a questionnaire evaluating individual satisfaction and quality of life was submitted to the patients. Results The mean age of patients at the time of surgery was 70 ± 10 years. The mean uncorrected and corrected monocular distance visual acuity (VA) were LogMAR 0.06 ± 0.10 and LogMAR 0.00 ± 0.08, respectively. The outcomes for the binocular uncorrected distance visual acuity were almost the same (LogMAR −0.04 ± 0.09). LogMAR −010 ± 0.15 and 0.02 ± 0.06 were measured for the binocular uncorrected intermediate and near VA, respectively. The distance-corrected visual acuity was maintained in mesopic conditions. The contrast sensitivity was similar to that obtained after implantation of a bifocal intraocular lens and did not decrease in mesopic conditions. The binocular defocus curve confirms good VA even in the intermediate distance range, with a moderate decrease of less than LogMAR 0.2 at −1.5 D, with respect to the best distance VA at 0 D defocus. Patient satisfaction was high. No discrepancy between the objective and subjective outcomes was evidenced. Conclusion The introduction of a third focus in diffractive multifocal intraocular lenses improves the intermediate vision with minimal visual discomfort for the patient. PMID:24124348

  3. Bacillus cereus panophthalmitis associated with intraocular gas bubble.

    PubMed Central

    al-Hemidan, A; Byrne-Rhodes, K A; Tabbara, K F

    1989-01-01

    It has become increasingly apparent that Bacillus cereus can cause a severe and devastating form of endophthalmitis following penetrating trauma by a metallic object. B. cereus is an uncommon aetiological agent in non-clostridial gas-forming infections. The patient studied in this single case report showed evidence of intraocular gas mimicking gas gangrene infection. The physiology of non-clostridial bacteria producing gas from anaerobic metabolic conditions is reviewed. Further intraocular and systemic complications which may be avoided by accurate and early diagnosis and the use of recommended treatment with antibiotics such as clindamycin. Images PMID:2493262

  4. New Hurricane Exhibit

    NASA Technical Reports Server (NTRS)

    2007-01-01

    A new exhibit in StenniSphere depicting NASA's role in hurricane prediction and research and SSC's role in helping the region recover from Hurricane Katrina. The cyclone-shaped exhibit focuses on the effects of the Aug. 29, 2005 storm and outlines how NASA is working to improve weather forecasting. Through photos, 3-D models and digital animations, the exhibit tells the story of what happened inside the storm and how NASA's scientific research can increase the accuracy of hurricane tracking and modeling.

  5. Intraocular caspofungin: in vitro safety profile for human ocular cells.

    PubMed

    Kernt, M; Kampik, A

    2011-07-01

    Endogenous Candida endophthalmitis is sight-threatening, difficult to treat and sometimes leads to loss of the eye. Only a few therapeutic agents are available for its treatment. Caspofungin is the first of a new class of antifungal drugs (echinocandins) with a high activity against Candida species, the most common pathogens found in endogenous endophthalmitis. This study investigates the safety profile of caspofungin for intraocular application in a cell-culture model. Endothelial toxicity of caspofungin was evaluated in cultured human corneas. Possible toxic effects of caspofungin (5-300 μg ml(-1)) in corneal endothelial cells (CEC), primary human trabecular meshwork cells (TMC) and primary human retinal pigment epithelium (RPE) cells were evaluated after 24 h and under conditions of inflammatory stress by treatment with tumour necrosis factor-alpha (TNF-α), lipopolysaccharides (LPS) or interleukin-6 (IL-6) and hydrogen peroxide (H(2)O(2)). Toxicity was evaluated by tetrazolium dye-reduction assay; cell viability was quantified by a microscopic live-dead assay. No corneal endothelial toxicity could be detected after 30 days of treatment with 75 μg ml(-1) of caspofungin. Concentrations up to 75 μg ml(-1) had no influence on CEC, TMC or RPE cell proliferation, or on cell viability when administered for 24 h. Exposure to H(2)O(2) did not increase cellular toxicity of caspofungin at concentrations of 5-50 μg ml(-1). After preincubation with TNF-α, LPS or IL-6 for 24 h followed by treatment with caspofungin for 24 h, no significant decrease in cell proliferation or viability was observed. This study showed no significant toxicity for caspofungin on CEC, TMC or RPE cells, or human corneal endothelium when administered in therapeutic concentrations up to 50 μg ml(-1).

  6. Development of fibrin-free intraocular lens with photochemical surface modification

    NASA Astrophysics Data System (ADS)

    Sato, Yuji; Tanizawa, Katsuya; Anai, Hiroyuki; Sato, Nobuhiro; Sato, Yuki; Ajiki, Tooru; Parel, Jean-Marie; Murahara, Masataka

    2004-07-01

    Having substituted the hydrophilic and hydrophobic groups alternately on the soft acrylic resin intraocular lens (IOL) surface by using an ArF excimer laser and a Xe2 excimer lamp, we have developed the IOL that is free from fibrin. Acrylic resin or PMMA lens has been used as an intraocular lens for 50 years. However, protein and fat are stuck onto the IOL surface after a long implantation, which opacifies the surface (after-cataract). Thus, we designed the micro domain structures of hydrophilic and hydrophobic groups on the IOL surface for fibrin-free. Firstly, the IOL was irradiated with the Xe2 excimer lamp in the presence of perfluoropolyether in order to make it hydrophobic. By this photochemical reaction, the CF3 functional groups were substituted on the IOL surface. Secondly, the ArF laser was projected on the IOL through the mask pattern in reduced size in the presence of water in order to be hydrophilic. With the photochemical reaction, the OH groups were substituted at the part exposed. The fibrin adsorption test of the modified IOL surface was carried out with FT-IR; which revealed that the fibrin-sticking rate of the treated sample has decreased by 23% compared with that of the non-treated sample. As a result, the fibrin-free IOL has been made by modifying the surface of the IOL to have the micro domain structures of the hydrophilic and hydrophobic groups that are arrayed alternately. In conclusion, the ideal intraocular lens has been demonstrated.

  7. Test Control Center exhibit

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Have you ever wondered how the engineers at John C. Stennis Space Center in Hancock County, Miss., test fire a Space Shuttle Main Engine? The Test Control Center exhibit at StenniSphere can answer your questions by simulating the test firing of a Space Shuttle Main Engine. A recreation of one of NASA's test control centers, the exhibit explains and portrays the 'shake, rattle and roar' that happens during a real test firing.

  8. Communicating Science through Exhibitions

    NASA Astrophysics Data System (ADS)

    Dusenbery, Paul

    2005-04-01

    It is critically important for the public to better understand the scientific process. Museum exhibitions are an important part of informal science education that can effectively reach public audiences as well as school groups. They provide an important gateway for the public to learn about compelling scientific endeavors. Science exhibitions also provide a marvelous opportunity for scientists to become engaged in the exhibit development process. The Space Science Institute (SSI) is a national leader in producing traveling science exhibitions and their associated educational programming (i.e. interactive websites, educator workshops, public talks, instructional materials). The focus of this presentation will be on two of its exhibit projects: MarsQuest (on tour for four years) and Alien Earths (its tour began early in 2005). MarsQuest is enabling millions of Americans to share in the excitement of the scientific exploration of Mars and to learn more about their own planet in the process. Alien Earths will bring origins-related research and discoveries to students and the American public. It has four interrelated exhibit areas: Our Place in Space, Star Birth, Planet Quest, and Search for Life. Exhibit visitors will explore the awesome events surrounding the birth of stars and planets; they will join scientists in the hunt for planets outside our solar system including those that may be in ``habitable zones'' around other stars; and finally they will be able to learn about how scientists are looking for signs of life beyond Earth. SSI is also developing interactive web sites based on exhibit themes. New technologies are transforming the Web from a static medium to an interactive environment with tremendous potential for informal education and inquiry-based investigations. This talk will focus on the role informal science projects play in effectively communicating science to a broad, public audience.

  9. [Postoperative opacification of posterior chamber intraocular lenses - a review].

    PubMed

    Schmidbauer, J M; Werner, L; Apple, D J; Pandey, S K; Izak, A M; Trivedi, R H; Macky, T A; Auffarth, G U; Peng, Q; Arthur, S N; Escobar-Gomez, M; Ma, L; Vargas, L G

    2001-09-01

    Postoperative opacification of intraocular lenses (IOLs) is a very unpleasant complication for the ophthalmic surgeon and the patient. We report on our experiences with opacification of different foldable IOL designs and rigid poly (methyl methacrylate) (PMMA) posterior chamber lenses.1. Snowflake degeneration of PMMA IOLs: This condition is an unanticipated and surprising late postoperative finding 8 to 15 years after implantation. In our opinion, this complication is probably not related to the PMMA biomaterial itself, but rather it appears to represent a manufacturing problem that has affected a selected, albeit large number of lenses manufactured in the 1980s-mid 1990s.2. Degeneration of UV absorber material and calcium deposits within the optic of hydrophilic IOLs: Two years postoperatively degenerations of UV absorber material and calcium deposits within the optic of single piece hydrophilic acrylic lenses SC60B-OUV manufactured by MDR (Medical developmental research Inc. Clearwater FL, USA) can occur. Although the precise mechanism is not fully known, it was assumed that these opacifications are due to premature aging of the UV blocking agent incorporated in the lens biomaterial and calcification.3. Calcification on the surface of the Bausch & Lomb Hydroviewtrade mark IOLs: Twelve to 15 months postoperatively granular surface calcifications in Hydroviewtrade mark IOLs occured. The mechanism is not fully understood. According to Bausch and Lomb studies, part of the components of the packaging contained silicone, which may have come off the packaging onto the lens optic, where it then appears to be a catalyst for calcium precipitation. The manufacturer has correlated a change in packaging with the appearance of the opacification. The manufacturer now believes that this problem has been solved. However, final verification will require a careful 1 - 2 years clinical study.4. Glistenings in the hydrophobic acrylic AcrySoftrade mark IOLs: The time frame of

  10. Retropupillary iris-claw intraocular lens in ectopia lentis in Marfan syndrome

    PubMed Central

    Faria, Mun Yueh; Ferreira, Nuno; Neto, Eliana

    2016-01-01

    Objective To report visual outcomes, complication rate, and safety of retropupillary iris-claw intraocular lens (ICIOL) in ectopia lentis in Marfan syndrome (MFS). Design Retrospective study. Methods Six eyes of three MFS patients with ectopia lentis underwent surgery for subluxation lens and retropupillary ICIOL implantation from October 2014 to October 2015 at the Department of Ophthalmology, Santa Maria Hospital in Lisbon, Portugal. Demographics, preoperative and postoperative best-corrected visual acuity (BCVA), and intraocular pressure were evaluated. Endothelium cell count was assessed using specular microscopy; anterior chamber depth was measured using Pentacam postoperatively; and intraocular lens position was viewed by ultrasound biomicroscopy. All patients were female; mean age was 20±14.264 years (range: 7–38 years). Results The average follow-up period was 6.66 months (range: 4–16 months). Preoperative BCVA was 0.568±0.149 logMAR units, and postoperative BCVA was 0.066±0.121 logMAR units. The mean BCVA gain was −0.502±0.221 on the logMAR scale. Postoperative average astigmatism and intraocular pressure were 1.292±0.697 mmHg (range: 0.5–2.25 mmHg) and 16 mmHg (range: 12–18 mmHg), respectively. The average endothelial cell density decreased from 3,121±178 cells/mm2 before surgery to 2,835±533 cells/mm2 after surgery (measured at last follow-up visit) and in the last follow-up, representing an average endothelial cell loss of 9.16%. Mean anterior chamber depth was 4.01 mm (±0.77 mm), as measured by Pentacam. No complications were found intra- or postoperatively in any of the six studied eyes. Conclusion Retropupillary ICIOL implantation is a safe and effective procedure in the treatment of aphakia in MFS eyes, without capsular support after surgery for ectopia lens. The six eyes that underwent lensectomy and retropupillary ICIOL implantation have had excellent visual outcomes with no complications so far. PMID:27382335

  11. Mid-infrared laser ablation of intraocular acrylic lenses

    NASA Astrophysics Data System (ADS)

    Spyratou, E.; Makropoulou, M.; Bacharis, C.; Serafetinides, A. A.

    2007-05-01

    Ablation rates measurements with free-running Er:YAG laser (λ=2.94 μm) were performed in hydrophilic acrylic intraocular lenses. We studied the role of water in the laser ablation mechanisms by using hydrophilic lenses with different concentrations of H II0 and D II0. A mathematical model simulated the experimental results.

  12. Unexplained heterochromia. Intraocular foreign body demonstrated by computed tomography.

    PubMed

    Barr, C C; Vine, A K; Martonyi, C L

    1984-01-01

    Standard radiographic techniques are often inadequate in demonstrating the presence and location of intraocular foreign bodies. Computerized axial tomography was used to confirm the presence of a metallic foreign body in a patient with heterochromia iridis and suspected ocular siderosis in whom no foreign material was found by conventional examination methods.

  13. Use of betaxolol in the reduction of elevated intraocular pressure.

    PubMed

    Radius, R L

    1983-06-01

    Forty eyes in 20 patients with elevated intraocular pressure were treated with either a 0.125% betaxolol ophthalmic solution or a placebo. After 2, 4, and 6 weeks of twice-daily therapy, the eyes receiving the betaxolol had a mean percent reduction in IOP greater than that in the eyes treated only with the drug vehicle (placebo). Both solutions were well tolerated.

  14. Trabeculectomy for traumatic hyphema with increased intraocular pressure.

    PubMed

    Graul, T A; Ruttum, M S; Lloyd, M A; Radius, R L; Hyndiuk, R A

    1994-02-15

    We reviewed the medical records of 11 consecutive patients who underwent trabeculectomy with anterior chamber washout and peripheral iridectomy as the primary surgical treatment for traumatic hyphema that was unresponsive to medical management. The mean intraocular pressure before surgery was 48 mm Hg. In ten of the patients the intraocular pressure was lowered to 21 mm Hg or lower after surgery and remained below that level up to the most recent follow-up visit, which ranged from eight to 97 months. One patient required a topical beta-blocker and oral acetazolamide to lower pressure to this level after surgery. Eight patients had visual acuity of 20/60 or better at last follow-up. Corneal blood staining occurred in eight patients. Compared with other techniques for surgical management of traumatic hyphema, trabeculectomy provides a means to keep intraocular pressure lowered while the remaining blood is clearing from the anterior chamber. Trabeculectomy with anterior chamber washout and peripheral iridectomy appears to be a safe and reliable procedure in the management of traumatic hyphemas in which medical management fails to control intraocular pressure.

  15. Unilateral phacoemulsification and intraocular lens implantation in a dachshund

    PubMed Central

    Kopala, Robyn L.

    2008-01-01

    A 1.5-year-old, spayed, female dachshund was presented with a cataract and lens-induced uveitis in the left eye. The cataract progressed from immature to hypermature in 4 months. Phacoemulsification and intraocular lens implantation was performed and the dog remains visual in the left eye 1 year post-surgery. PMID:19119375

  16. Swamp to Space exhibit

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The menacing-looking alligator is really harmless. It is one of the realistic props to help convince visitors that the feel of the swamp is real in StenniSphere's Swamp to Space exhibit at John C. Stennis Space Center in Hancock County, Miss. The historical section of the Swamp to Space exhibit tells the story of why and how Stennis Space Center came to be. It also pays tribute to the families who moved their homes to make way for the space age in Mississippi.

  17. Pictures at an Exhibition.

    ERIC Educational Resources Information Center

    Kunz, Walter S., Jr.

    1997-01-01

    Describes the Youth Art Month exhibit in Howard County (Maryland) where students submitted their art focusing on school buildings and their interiors. Their art reveals concerns and desires about overcrowding, space utilization, school building height, outside lighting, solitude needs, and visual stimulation. The artwork is discussed in terms of…

  18. Exhibitions in Sight.

    ERIC Educational Resources Information Center

    Wasserman, Burton

    1978-01-01

    Early in the eighteenth century, Pompeii was discovered, a city that had been hidden for sixteen centuries by volcanic lava. There is a traveling exhibition of the sculptures, friezes, mosaics, and paintings being shown around the United States. Described is the history and contents of "Pompeii--A.D. 79." (RK)

  19. 1989 Architectural Exhibition Winners.

    ERIC Educational Resources Information Center

    School Business Affairs, 1990

    1990-01-01

    Winners of the 1989 Architectural Exhibition sponsored annually by the ASBO International's School Facilities Research Committee include the Brevard Performing Arts Center (Melbourne, Florida), the Capital High School (Santa Fe, New Mexico), Gage Elementary School (Rochester, Minnesota), the Lakewood (Ohio) High School Natatorium, and three other…

  20. Exhibition in Sight

    ERIC Educational Resources Information Center

    Wasserman, Burton

    1978-01-01

    Ludwig Mies van der Rohe is known primarily as an architect. However, he also designed chairs and tables. Discusses an exhibit held in New York City a few months ago which showed how well the famous architect achieved his goals in the area of furniture design. (Author/RK)

  1. Spectral analysis and comparison of mineral deposits forming in opacified intraocular lens and senile cataractous lens

    NASA Astrophysics Data System (ADS)

    Lin, Shan-Yang; Chen, Ko-Hwa; Lin, Chih-Cheng; Cheng, Wen-Ting; Li, Mei-Jane

    2010-10-01

    This preliminary report was attempted to compare the chemical components of mineral deposits on the surfaces of an opacified intraocular lens (IOL) and a calcified senile cataractous lens (SCL) by vibrational spectral diagnosis. An opacified intraocular lens (IOL) was obtained from a 65-year-old male patient who had a significant decrease in visual acuity 2-years after an ocular IOL implantation. Another SCL with grayish white calcified plaque on the subcapsular cortex was isolated from a 79-year-old male patient with complicated cataract after cataract surgery. Optical light microscope was used to observe both samples and gross pictures were taken. Fourier transform infrared (FT-IR) and Raman microspectroscopic techniques were employed to analyze the calcified deposits. The curve-fitting algorithm using the Gaussian function was also used to quantitatively estimate the chemical components in each deposit. The preliminary results of spectral diagnosis indicate that the opacified IOL mainly consisted of the poorly crystalline, immature non-stoichiometric hydroxyapatite (HA) with higher content of type B carbonated apatites. However, the calcified plaque deposited on the SCL was comprised of a mature crystalline stoichiometric HA having higher contents of type A and type B carbonate apatites. More case studies should be examined in future.

  2. Late-onset Citrobacter koseri endophthalmitis with suture exposure after secondary intraocular lens implantation.

    PubMed

    Kang, Hae Min; Chung, Eun Jee

    2011-08-01

    A 54-year-old male patient was seen in clinic for ocular pain and decreased vision in the right eye with duration of two days. He underwent a cataract operation for his right eye 12 years ago, then a sclera-fixated secondary intraocular implantation and pars plana vitrectomy three years ago due to intraocular lens dislocation. At the initial visit, his visual acuity was restricted to the perception of hand motion. An edematous cornea, cells, flare with hypopyon, and exposed suture material at were observed at the six o'clock direction by slit lamp. Vitreous opacity was noted from B-scan ultrasonography. The patient was diagnosed with late-onset endophthalmitis and an intravitreal cocktail injection was done. On the next day, the hypopyon was aggravated, and therefore a pars plana vitrectomy was performed. A vitreous culture tested positive for Citrobacter koseri. After 12 weeks, the best corrected visual acuity of the right eye improved to 0.7 and a fundus examination revealed a relatively normal optic disc and retinal vasculature. We herein report the first case of endophthalmitis caused by Citrobacter koseri in Korea. Exposed suture material was suspected as the source of infection in this case and prompt surgical intervention resulted in a relatively good visual outcome.

  3. Effects of phacoemulsification and intraocular lens implantation combined with ciliarotomy in the treatment of angle-closure glaucoma with cataract

    PubMed Central

    Li, Bo; Wang, Feng-Yun; Lv, Tai-Liang; Zhu, Yu

    2016-01-01

    The aim of the present study was to examine the effects of phacoemulsification and intraocular lens implantation combined with ciliarotomy in the treatment of angle-closure glaucoma with cataract in the elderly. A total of 68 patients were consecutively selected and divided into the control group with 33 cases (48 eyes) and the observation group with 35 cases (53 eyes). Cataract surgery combined with trabeculectomy was performed on the patients in the control group and phacoemulsification cataract extraction combined with ciliarotomy was performed on the subjects in the observation group, to compare postoperative effects and complications. Following surgery, the visual acuity of patients in the two groups significantly improved, intraocular pressure decreased, and improvement of the observation group was more evident (P<0.05). Following surgery, the depth of central anterior chamber and width of chamber angle of patients in two groups was increased, and improvement of the observation group was significantly more evident (P<0.05). Additionally, the incidence of complications, including corneal swelling, shallow of anterior chamber, fibrinous exudate in iris, and filtering bleb leaking and following cataract removal, of patients in the observation group was significantly reduced compared to the control group (P<0.05). In summary, the results of the present study show that, phacoemulsification and intraocular lens implantation combined with ciliarotomy in the treatment of angle-closure glaucoma with cataract in the elderly is a safe and effective method and should be applied in the clinic. PMID:27698750

  4. Starship 2040 Exhibit

    NASA Technical Reports Server (NTRS)

    2001-01-01

    This photograph shows the Starship 2040 leaving the Marshall Space Flight Center (MSFC) for the exhibit site. Developed by the Space Transportation Directorate at MSFC, the Starship 2040 exhibit is housed in a 48-ft (14.6-m) tractor and trailer rig, permitting it to travel around the Nation, demonstrating NASA's vision of what commercial spaceflight might be like 40 years from now. All the irnovations suggested aboard the exhibit, automated vehicle health monitoring systems, high-energy propulsion drive, navigational aids and emergency and safety systems, are based on concepts and technologies now being studied at NASA Centers and partner institutions around the Nation. NASA is the nation's premier agency for development of the space transportation system, including future-generation reusable launch vehicles. Such systems, the keys to a 'real' Starship 2040, require revolutionary advances in critical aerospace technologies, from thermal, magnetic, chemical, and propellantless propulsion systems to new energy sources such as space solar power or antimatter propulsion. These and other advances are now being studied, developed, and tested at NASA field centers and partner institutions all over the Nation.

  5. Starship 2040 Exhibit

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This photograph shows onlookers viewing displays within the Starship 2040 exhibit on display at Joe Davis Stadium in Huntsville, Alabama. Developed by the Space Transportation Directorate at Marshall Space Flight Center (MSFC), the Starship 2040 exhibit is housed in a 48-ft (14.6-m) tractor and trailer rig, permitting it to travel around the Nation, demonstrating NASA's vision of what commercial spaceflight might be like 40 years from now. All the irnovations suggested aboard the exhibit (automated vehicle health monitoring systems, high-energy propulsion drive, navigational aids, and emergency and safety systems) are based on concepts and technologies now being studied at NASA Centers and partner institutions around the Nation. NASA is the Nation's premier agency for development of the space transportation system, including future-generation reusable launch vehicles. Such systems, the keys to a 'real' Starship 2040, require revolutionary advances in critical aerospace technologies, from thermal, magnetic, chemical, and propellantless propulsion systems to new energy sources such as space solar power or antimatter propulsion. These and other advances are now being studied, developed, and tested at NASA field centers and partner institutions all over the Nation.

  6. Starship 2040 Exhibit

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This photograph shows Justin Varnadore, son of a Marshall TV employee, at the controls of one of the many displays within the Starship 2040 exhibit on display at Joe Davis Stadium in Huntsville, Alabama. Developed by the Space Transportation Directorate at Marshall Space Flight Center (MSFC), the Starship 2040 exhibit is housed in a 48-ft (14.6-m) tractor and trailer rig, permitting it to travel around the Nation, demonstrating NASA's vision of what commercial spaceflight might be like 40 years from now. All the irnovations suggested aboard the exhibit (automated vehicle health monitoring systems, high-energy propulsion drive, navigational aids, and emergency and safety systems) are based on concepts and technologies now being studied at NASA Centers and partner institutions around the Nation. NASA is the Nation's premier agency for development of the space transportation system, including future-generation reusable launch vehicles. Such systems, the keys to a 'real' Starship 2040, require revolutionary advances in critical aerospace technologies, from thermal, magnetic, chemical, and propellantless propulsion systems to new energy sources such as space solar power or antimatter propulsion. These and other advances are now being studied, developed, and tested at NASA field centers and partner institutions all over the Nation.

  7. Online Exhibits & Concept Maps

    NASA Astrophysics Data System (ADS)

    Douma, M.

    2009-12-01

    Presenting the complexity of geosciences to the public via the Internet poses a number of challenges. For example, utilizing various - and sometimes redundant - Web 2.0 tools can quickly devour limited time. Do you tweet? Do you write press releases? Do you create an exhibit or concept map? The presentation will provide participants with a context for utilizing Web 2.0 tools by briefly highlighting methods of online scientific communication across several dimensions. It will address issues of: * breadth and depth (e.g. from narrow topics to well-rounded views), * presentation methods (e.g. from text to multimedia, from momentary to enduring), * sources and audiences (e.g. for experts or for the public, content developed by producers to that developed by users), * content display (e.g. from linear to non-linear, from instructive to entertaining), * barriers to entry (e.g. from an incumbent advantage to neophyte accessible, from amateur to professional), * cost and reach (e.g. from cheap to expensive), and * impact (e.g. the amount learned, from anonymity to brand awareness). Against this backdrop, the presentation will provide an overview of two methods of online information dissemination, exhibits and concept maps, using the WebExhibits online museum (www.webexhibits.org) and SpicyNodes information visualization tool (www.spicynodes.org) as examples, with tips on how geoscientists can use either to communicate their science. Richly interactive online exhibits can serve to engage a large audience, appeal to visitors with multiple learning styles, prompt exploration and discovery, and present a topic’s breadth and depth. WebExhibits, which was among the first online museums, delivers interactive information, virtual experiments, and hands-on activities to the public. While large, multidisciplinary exhibits on topics like “Color Vision and Art” or “Calendars Through the Ages” require teams of scholars, user interface experts, professional writers and editors

  8. Space Shuttle Cockpit exhibit

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Want to sit in the cockpit of the Space Shuttle and watch astronauts work in outer space? At StenniSphere, you can do that and much more. StenniSphere, the visitor center at John C. Stennis Space Center in Hancock County, Miss., presents 14,000-square-feet of interactive exhibits that depict America's race for space as well as a glimpse of the future. StenniSphere is open free of charge from 9 a.m. to 5 p.m. daily.

  9. Starship 2040 Exhibit

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This photograph shows the Starship 2040 on display at Joe Davis Stadium in Huntsville, Alabama. Developed by the Space Transportation Directorate at Marshall Space Flight Center (MSFC), the Starship 2040 exhibit is housed in a 48-ft (14.6-m) tractor and trailer rig, permitting it to travel around the Nation, demonstrating NASA's vision of what commercial spaceflight might be like 40 years from now. All the irnovations suggested aboard the exhibit (automated vehicle health monitoring systems, high-energy propulsion drive, navigational aids, and emergency and safety systems) are based on concepts and technologies now being studied at NASA Centers and partner institutions around the Nation. NASA is the Nation's premier agency for development of the space transportation system, including future-generation reusable launch vehicles. Such systems, the keys to a 'real' Starship 2040, require revolutionary advances in critical aerospace technologies, from thermal, magnetic, chemical, and propellantless propulsion systems to new energy sources such as space solar power or antimatter propulsion. These and other advances are now being studied, developed, and tested at NASA field centers and partner institutions all over the Nation.

  10. Intraocular pressure following ECCE, phacoemulsification, and PC-IOL implantation.

    PubMed

    Kooner, K S; Cooksey, J C; Perry, P; Zimmerman, T J

    1988-09-01

    Abnormal intraocular pressure (IOP), either transient or permanent, may follow extracapsular cataract extraction (ECCE) with phacoemulsification (PE) and posterior chamber intraocular lens (PC-IOL) implantation. We retrospectively studied IOP measurements at different intervals post ECCE and PE in 242 eyes of 211 patients: 105 males, 106 females, 198 Caucasians and 13 blacks. Elevated IOP (greater than 23 mm Hg) was observed in 20 eyes (8.2%). Only two patients (0.8%) had persistent (greater than 3 months) IOP elevation and needed antiglaucoma therapy. Six more eyes (2.5%), however, developed glaucoma after 1 year. Hence, the incidence of secondary pseudophakic glaucoma at the conclusion of this study was 3.3%. No patient required laser or other mechanical surgery for IOP control. ECCE and PE with PC-IOL does not appear to adversely affect IOP. Patients, however, must be followed closely, as some may develop glaucoma months after surgery.

  11. Multifocal Toric Intraocular Lens for Traumatic Cataract in a Child

    PubMed Central

    Zeng, Yanfeng; Fan, Licheng; Lu, Peirong

    2016-01-01

    A child suffering from traumatic cataract and corneal astigmatism of 2.14 D had a phacoemulsification operation and implantation of a ReSTOR Toric intraocular lens (IOL) to correct the astigmatism. The primary outcome measurements were the uncorrected distance visual acuity (UDVA), uncorrected near vision at 40 cm, intraocular pressure, spherical equivalent refraction, residual astigmatism, corneal astigmatism, presence of unusual optical phenomena, and use of spectacles. At 7 months postoperatively, UDVA was maintained between 16/20 and 24/20, near vision was between J1 and J3, residual spherical refraction was 0–0.37 D, and residual refractive cylinder was between 0 and 0.67 D. A multifocal toric IOL can provide the possibility of satisfactory vision for both distant and near conditions without the use of spectacles to meet children's needs when studying and doing sports. Additionally, binocular vision can be reconstructed. This intervention, therefore, seems to be a satisfactory alternative. PMID:28101039

  12. Intra-ocular pressure normalization technique and equipment

    NASA Technical Reports Server (NTRS)

    Baehr, E. F. (Inventor)

    1979-01-01

    A method and apparatus is described for safely reducing abnormally high intraocular pressure in an eye during a predetermined time interval. This allows maintenance of normal intraocular pressure during glaucoma surgery. A pressure regulator of the spring-biassed diaphragm type is provided with additional bias by a column of liquid. The hypodermic needle can be safely inserted into the anterior chamber of the eye. Liquid is then bled out of the column to reduce the bias on the diaphragm of the pressure regulator and, consequently, the output pressure of the regulator. This lowering pressure of the regulator also occurs in the eye by means of a small second bleed path provided between the pressure regulator and the hypodermic needle.

  13. Intraocular lens exchange-removing the optic intact

    PubMed Central

    Lee, Matthew Hao; Webster, Diane Lesley

    2016-01-01

    Current practice for intraocular lens (IOL) exchange is to cut the optic of the posterior chamber intraocular lens (PCIOL) prior to removing it. Great care must be taken during this maneuver to avoid a posterior capsular tear. Removing the haptics from the fibrosed capsule can also be hazardous, as it may result in zonular stress and dehiscence. A technique is described for performing foldable (one-piece acrylic) IOL removal without cutting the optic. Careful visco-dissection of the haptics with a low viscosity ophthalmic viscosurgical device (OVD) in the fibrosed peripheral capsular tunnel avoids zonular or capsular stress. Internal wound enlargement permits foldable IOL removal in one piece, whilst preserving a self-sealing sutureless corneal wound. This technique may enhance the safety and efficacy of foldable IOL exchange. PMID:27366699

  14. Management of the posterior capsule during pediatric intraocular lens implantation.

    PubMed

    Buckley, E G; Klombers, L A; Seaber, J H; Scalise-Gordy, A; Minzter, R

    1993-06-15

    One of the major obstacles in pediatric intraocular lens implantation has been the subsequent dense opacification of the posterior capsule. We used a modification of the standard pediatric cataract surgical procedure, which involved endocapsular cataract extraction, posterior chamber intraocular lens implantation, pars plana posterior capsulotomy, and pars plana anterior vitrectomy in 20 consecutive patients with unilateral traumatic, radiation-induced, and developmental cataracts. Visual axes were rapidly restored in all patients without further intervention for posterior capsule opacification. Visual acuity returned to 20/40 or better in all patients and 75% of all patients (15 patients) reached maximum improvement by five weeks. No complications attributed to intraoperative removal of the posterior capsule occurred.

  15. Intraocular Penetration of Intravenous Micafungin in Inflamed Human Eyes

    PubMed Central

    Sawada, Akira; Suemori, Shinsuke; Kawakami, Hideaki; Niwa, Yoshiaki; Kondo, Yuji; Ohkusu, Kiyofumi; Yamada, Noriaki; Ogura, Shinji; Yaguchi, Takashi; Nishimura, Kazuko; Kishino, Satoshi

    2013-01-01

    Eight eyes of 7 patients with fungal disease received intravenous injections of 150 to 300 mg micafungin, and samples of blood, cornea, retina-choroid, aqueous humor, and vitreous humor were collected. The micafungin levels in all collected samples exceeded the MICs; however, the levels in the vitreous and aqueous humors were lower. Our findings suggest that intravenous micafungin should be given in combination with intravitreal antifungal agents after vitrectomy in severe cases of intraocular fungal diseases. PMID:23689706

  16. Towards a Completely Implantable, Light-Sensitive Intraocular Retinal Prosthesis

    DTIC Science & Technology

    2007-11-02

    electronic retinal prosthesis is under development to treat retinitis pigmentosa and age-related macular degeneration, two presently incurable...34Preservation of the inner retina in retinitis pigmentosa . A morphometric analysis," Arch Ophthalmol, vol. 115, no. 4, pp. 511-515, Apr.1997...Towards a completely implantable, light-sensitive intraocular retinal prosthesis. M.S. Humayun, J.D. Weiland, B. Justus1, C. Merrit1, J. Whalen, D

  17. Intraocular lens providing good vision 23 years after placement.

    PubMed Central

    Gillan, J. G.

    1977-01-01

    A Ridley Perspex lens was placed in the posterior chamber of a man's eye 23 years ago; 20/25 vision has been maintained since. This technique, first carried out in 1949, has been abandoned because of the high incidence of lens dislocation and glaucoma, but many modified versions of the lens have been produced. Implantation of intraocular lenses is still considered experimental, though careful selection of cases and meticulous surgical procedure can yield good results. PMID:608150

  18. Intraocular pressure with rebound tonometry and effects of topical intraocular pressure reducing medications in guinea pigs

    PubMed Central

    Di, Yue; Luo, Xiu-Mei; Qiao, Tong; Lu, Na

    2017-01-01

    AIM To investigate the intraocular pressure (IOP) of adult guinea pig eyes with rebound tonometry (RBT), and assess the effects of four distinctive topical IOP reducing medications including Carteolol, Brimonidine, Brinzolamide and Latanoprost. METHODS The IOPs of twenty-four 12-week-old guinea pigs (48 eyes) were measured every two hours in one day with RBT as baselines. All the animals were then divided into four groups (Carteolol, Brimonidine, Brinzolamide and Latanaprost groups, n=6). The IOPs were measured and compared to the baseline 1, 2, 3, 5, 7, 9, 15 and 24h after treatment. RESULTS The mean baseline IOP of 24 guinea pigs (48 eyes) was 10.3±0.36 mm Hg (6-13 mm Hg) and no binocular significant differences of IOPs were observed (t=1.76, P>0.05). No significant difference of IOP in Carteolol group at each time point was observed before and after treatment (t=1.48, P>0.05). In Brimonidine group, IOP was 2.2±1.9 mm Hg lower than the baseline after one hour (t=3.856, P=0.003) and lasted for one hour. In Brinzolamide group, IOP was 1.4±1.1 mm Hg lower than the baseline after one hour (t=4.53, P=0.001) and lasted for 7h and the IOP declined most at 3h. In Latanaprost group, IOP was 2.1±1.3 mm Hg lower than the baseline after one hour (t=6.11, P=0.001) and lasted for one hour. CONCLUSION The IOP of guinea pig eyes is relatively stable compared to human eyes. In four reducing IOP medications, no significant effect of Carteolol is observed. Brinzolamide has the longest duration, while the Brimonidine has the shortest duration and the maximum level of treatment. PMID:28251075

  19. [The Use of Polymers for Intraocular Lenses in Cataract Surgery].

    PubMed

    Fizia-Orlicz, Anna; Misiuk-Hojło, Marta

    2015-01-01

    According to the World Health Organization, cataract remains the leading cause of the curable visual impairment worldwide. Cataract can only be cured by surgery during which the cloudy lens is replaced with an artificial intraocular lens. It is one of the most common surgeries being performed worldwide. There are age-related, congenital, traumatic and metabolic types of cataract which have been distinguished. Age-related cataract is the most common one and it affects people over 60 with the greatest frequency. In reference to patients whose cornea does not fulfill the requirements for a standard refractive surgery, the number of refractive intraocular lens replacement is increasing. Manufacturers aim to enhance materials in order to minimize surgical complication while increasing the patient’s eyesight. The increase in average lifespan along with patients’ expectations stimulate competition among manufacturers who bring new products and solutions into to the market. There is an augmented demand for premium lenses such as toric, multifocal or accommodating. These lenses bring patients the promise of life without the need for wearing glasses. As far as the main materials used in the production of intraocular lens are concerned, there are hydrophobic, hydrophilic, acrylic and silicone lenses in use. In this paper the author discusses characteristics as well as advantages and disadvantages of the above-mentioned materials. The associated surgical complications and the new areas of development regarding the materials used in lenses manufacturing are also examined.

  20. [The efficacy of treating patients with intraocular hemorrhages with emoxypin].

    PubMed

    Mokhammad, I; Cherkasov, I S

    1990-01-01

    Emoxipin, a home-made preparation approved by the Pharmacological Committee for clinical usage in 1986, is a retinal protector. Its usage is indicated for treatment of chorioretinitis, diabetic retinopathy, thrombosis of retinal vessels as well as to protects the retina from a damaging action of light of high intensity. In order to study therapeutic effectiveness of emoxipin in intraocular hemorrhages of different genesis, the preparation was used subconjunctivally, 0.5 ml of a 1% solution daily for 10-15 days. Emoxipin was used in 29 patients (29 eyes) with intraocular hemorrhages, of them, due to contusion of the eye--in 19, hypertonic disease--in 6, thrombosis of the central retinal vein--in 2, after intraocular operations--in 2 patients. As a result of the treatment, partial or almost total resolution of hemorrhages and a rise of visual acuity of different degree were recorded in all patients. Before treatment, visual acuity was from light perception to 0.04 in 26 eyes, from 0.09 to 0.3 in 3 eyes. After treatment, it rose to 0.1-0.2 in 12 eyes, to 0.3-1.0--in 17 eyes.

  1. Validation of sensor for postoperative positioning with intraocular gas

    PubMed Central

    Brodie, Frank L; Woo, Kelly Y; Balakrishna, Ashwin; Choo, Hyuck; Grubbs, Robert H

    2016-01-01

    Purpose Surgical repair of retinal attachment or macular hole frequently requires intraocular gas. This necessitates specific postoperative positioning to improve outcomes and avoid complications. However, patients struggle with correct positioning. We have developed a novel sensor to detect the position of the gas bubble in the eye and provide feedback to patients in real time. In this paper, we determine the specificity and sensitivity of our sensor in vitro using a model eye. Methods We assessed the reliability of our sensor to detect when a gas bubble has deviated off a model retinal break in a model eye. Various bubble sizes representing the intraocular kinetics of sulfur hexafluoride gas and varying degrees of deviation from the correct position were tested using the sensor attached to a mannequin head with a model eye. Results We recorded 36 data points. The sensor acted appropriately in 33 (91.7%) of them. The sensor triggered the alarm every time the bubble deviated off the break (n=15, sensitivity =100%). However, it triggered the alarm (falsely) 3/21 times when the bubble was correctly positioned over the retinal break (specificity =86%). Conclusion Our device shows excellent sensitivity (100%) and specificity (86%) in detecting whether intraocular gas is tamponading a retinal break in a model eye. PMID:27307698

  2. Nocturnal blood pressure and intraocular pressure measurement in glaucoma patients and healthy controls.

    PubMed

    Follmann, P; Palotás, C; Süveges, I; Petrovits, A

    Daytime and nocturnal intraocular pressure (IOP) values and systemic blood pressure (BP) values were compared in 60 non-glaucomatous controls, 54 glaucoma patients with normal visual field, and 46 glaucoma patients with visual field loss. The daytime IOP was measured with a Goldmann applanation tonometer and the nocturnal IOP with a Bio-Rad-Tono-Pen 2. The BP was measured with either a mercury manometer or with a Meditech ABPM-02 Ambulatory Blood Pressure Monitor, which took BP readings at 60 minute intervals. A tendency towards increasing IOP and decreasing BP was detected in the non-glaucomatous controls, within normal limits, and pathological changes of IOP and BP were observed with a significantly high occurrence (5% > P > 2%; Pearson's chi 2-test) in the glaucoma group with visual field loss.

  3. Spontaneous fracture of an implanted posterior chamber polyimide intraocular lens haptic: a case report.

    PubMed

    Kang, Haemin; Han, Kyung Eun; Kim, Tae-im; Kim, Eung Kweon

    2014-03-01

    A 57-year-old male patient visited our clinic for decreased visual acuity in the right eye for 10 days. He denied any trauma history, but recalled that the symptom developed after straining. He had undergone uncomplicated phacoemulsification and posterior chamber intraocular lens (IOL) implantation in the bag of the right eye 11 years ago. The IOL was a three-piece silicone polyimide-haptics design. On slit-lamp examination, the IOL optic and proximal part of nasal fractured haptic were found in the anterior chamber. The distal part of fractured haptic was observed in the capsular bag. He underwent IOL exchange. The fracture site of the haptic was near the optic-haptic junction. This is the unique case report of a spontaneous fracture of an implanted posterior chamber polyimide IOL haptic, which implies the possibility of IOL haptic fracture in various haptic materials.

  4. Keeping an eye on dialysis: the association of hemodialysis with intraocular hypertension.

    PubMed

    William, Jeffrey H; Gilbert, Aubrey L; Rosas, Sylvia E

    2015-11-01

    Intraocular hypertension is common during hemodialysis. Dialysis disequilibrium syndrome and intraocular hypertension occur via similar pathophysiologic mechanisms. These mechanisms may contribute to the development of glaucoma and cataracts in a patient population already at high risk for ocular abnormalities, given the common risk factors for chronic kidney disease and impaired aqueous humor outflow. We describe a patient with complicated diabetes mellitus, end-stage renal disease, and recent cataract surgery who developed severe intraocular hypertension during hemodialysis. We recommend increased awareness of the symptoms of intraocular hypertension and subsequent ophthalmologic surveillance in order to prevent long-term visual complications.

  5. Classification of feline intraocular neoplasms based on morphology, histochemical staining, and immunohistochemical labeling.

    PubMed

    Grahn, Bruce H; Peiffer, Robert L; Cullen, Cheryl L; Haines, Deborah M

    2006-01-01

    The objectives of this study were to evaluate morphologic, histochemical, and immunohistochemical characteristics of well-differentiated and anaplastic intraocular neoplasms of cats, and to develop a diagnostic algorithm for, and investigate the association of ruptured lenses with these neoplasms. Seventy-five feline globes with intraocular neoplasms were stained with hematoxylin and eosin and examined by light microscopy. Morphologic diagnoses included 33 intraocular sarcomas, 17 diffuse iris melanomas, 15 lymphosarcomas, three ciliary adenomas, one metastatic carcinoma, and six undifferentiated intraocular neoplasms. Sections of these globes were then stained with periodic acid Schiff (PAS), and immunohistochemical (IHC) labels for various cellular markers. Histochemical staining and IHC labeling confirmed cellular differentiation in 73/75 neoplasms but was discordant with morphologic diagnoses in 8/75. These included four neoplasms morphologically diagnosed as lymphosarcomas but which expressed differentiation antigens consistent with melanoma (n = 3) or ciliary adenocarcinoma (n = 1), and four tumors morphologically diagnosed as intraocular sarcomas that expressed differentiation antigens for melanoma (n = 2), metastatic carcinoma (n = 1), or remained undifferentiated (n = 1). Immunohistochemical labeling suggested a diagnosis in 5/6 morphologically undifferentiated neoplasms including one intraocular sarcoma, two diffuse iridal melanomas, and two ciliary adenocarcinomas. Based upon morphologic, histochemical, and IHC characterization, ruptured lens capsules were detected in 28/30 intraocular sarcomas, 3/24 diffuse iris melanomas and 1/11 lymphosarcomas, but not in ciliary epithelial neoplasms, metastatic carcinomas, or undifferentiated intraocular neoplasms. An algorithm is provided that facilitates stain and IHC label selection for differentiating anaplastic intraocular feline neoplasms.

  6. The role of pili in Bacillus cereus intraocular infection.

    PubMed

    Callegan, Michelle C; Parkunan, Salai Madhumathi; Randall, C Blake; Coburn, Phillip S; Miller, Frederick C; LaGrow, Austin L; Astley, Roger A; Land, Craig; Oh, So-Young; Schneewind, Olaf

    2017-03-20

    Bacterial endophthalmitis is a potentially blinding intraocular infection. The bacterium Bacillus cereus causes a devastating form of this disease which progresses rapidly, resulting in significant inflammation and loss of vision within a few days. The outer surface of B. cereus incites the intraocular inflammatory response, likely through interactions with innate immune receptors such as TLRs. This study analyzed the role of B. cereus pili, adhesion appendages located on the bacterial surface, in experimental endophthalmitis. To test the hypothesis that the presence of pili contributed to intraocular inflammation and virulence, we analyzed the progress of experimental endophthalmitis in mouse eyes infected with wild type B. cereus (ATCC 14579) or its isogenic pilus-deficient mutant (ΔbcpA-srtD-bcpB or ΔPil). One hundred CFU were injected into the mid-vitreous of one eye of each mouse. Infections were analyzed by quantifying intraocular bacilli and retinal function loss, and by histology from 0 to 12 h postinfection. In vitro growth and hemolytic phenotypes of the infecting strains were also compared. There was no difference in hemolytic activity (1:8 titer), motility, or in vitro growth (p > 0.05, every 2 h, 0-18 h) between wild type B. cereus and the ΔPil mutant. However, infected eyes contained greater numbers of wild type B. cereus than ΔPil during the infection course (p ≤ 0.05, 3-12 h). Eyes infected with wild type B. cereus experienced greater losses in retinal function than eyes infected with the ΔPil mutant, but the differences were not always significant. Eyes infected with ΔPil or wild type B. cereus achieved similar degrees of severe inflammation. The results indicated that the intraocular growth of pilus-deficient B. cereus may have been better controlled, leading to a trend of greater retinal function in eyes infected with the pilus-deficient strain. Although this difference was not enough to significantly alter the severity

  7. [Penetrating ocular trauma with intraocular foreign body].

    PubMed

    Musat, O; Ochinciuc, Uliana; Gutu, Tatiana; Cristescu, T R; Coman, Corina

    2012-01-01

    We present the case of a 65 years old pacient which was admitted for the sudden decrease of visual acuity in the left eye, accompanied by ocular pain and conjunctival hiperemia, simptoms appeared after an ocular trauma. After the clinical and paraclinical examination we determined the diagnosis of OS: Penetrating ocular trauma with retention of a foreign body; posttraumatic cataract. Surgical treatement was warrented and we performed OS : Facoemulsification + PFK implant in sulcus + 23 Ga posterior vitrectomy + peeling of the posterior hyaloid membrane + extraction of the foreign body + LASER endofotocoagulation + transscleral cryotherapy + SF6 gas injection. The post-operatory evolution was favorable.

  8. Optical bench performance of a novel trifocal intraocular lens compared with a multifocal intraocular lens

    PubMed Central

    Lee, Shinwook; Choi, Myoung; Xu, Zaiwei; Zhao, Zeyu; Alexander, Elsinore; Liu, Yueai

    2016-01-01

    Purpose The purpose of this study is to compare the optical characteristics of the novel PanOptix presbyopia-correcting trifocal intraocular lens (IOL) and the multifocal ReSTOR +3.0 D IOL, through in vitro bench investigations. Methods The optical characteristics of AcrySof® IQ PanOptix™ (PanOptix) and AcrySof® IQ ReSTOR +3.0 D (ReSTOR +3.0 D) IOLs were evaluated by through-focus Badal images, simulated headlight images, and modulation transfer function (MTF) measurements which determine resolution, photic phenomena, and image quality. Through-focus Badal images of an Early Treatment of Diabetic Retinopathy Study chart were recorded at both photopic and mesopic pupil sizes. Simulated headlight images were taken on an MTF bench with a 50-μm pinhole target and a 5.0 mm pupil at the distance focus of the IOL. MTF curves were measured with a 3.0 mm pupil, and spatial frequencies equivalent to 20/40 and 20/20 visual acuities were recorded to illustrate the through-focus MTF curves. Far-, intermediate-, and near-focus MTF values were obtained. Results Bench Badal image testing and MTF measurements showed that PanOptix has a near focus at a distance of 42 cm and an additional intermediate focus at a distance of about 60 cm. The near focus for ReSTOR +3.0 D is at 45 cm. PanOptix and ReSTOR +3.0 D have comparable photopic distances and near MTF values. Additionally, PanOptix provided a substantial continuous range of vision from distance to intermediate and to near compared with ReSTOR +3.0 D. The halo propensity for PanOptix was slightly higher than that for ReSTOR +3.0 D. Conclusion Laboratory-based in vitro simulations showed that PanOptix trifocal IOL has comparable resolution and image quality performance in distance and near foci compared with ReSTOR +3.0 D IOL. PanOptix showed better resolution and image quality performance at the intermediate focus than ReSTOR +3.0 D IOL. PMID:27330273

  9. Otolithic influences on extraocular and intraocular muscles

    NASA Technical Reports Server (NTRS)

    Gernandt, B. E.

    1973-01-01

    Selective stimulation of utricular gravireceptors leads to gross activation of the bulbar reticular formation where a strong interaction with evoked spino-bulbo-spinal reflex activity occurs. The utricular neurons encountered by microelectrodes in the lateral vestibular nuclei show four types of elicited activity; two of these display an increased firing rate, and two exhibit pronounced inhibitory effects. Application of a stimulus of long duration and constant intensity to the utricle has shown that rapid adaptation of the peripheral receptors is a prominent feature. The effects of selective utricular stimulation upon eye movements, as recorded by the corneoretinal potential method, have been studied in experiments on cats and monkeys and it can be firmly stated that prolonged stimulation of the utricle can evoke strong primary nystagmus, followed by a secondary nystagmus at the cessation of stimulation. The action of utricular stimulation on ocular reflexes has been examined further, with particular attention to evoked pupillary reactions in both cats and monkeys: constriction during the fast phase of the brisk conjugate eye movement, and dilatation during the flow phase.

  10. Aquaporin deletion in mice reduces intraocular pressure and aqueous fluid production.

    PubMed

    Zhang, Duo; Vetrivel, L; Verkman, A S

    2002-06-01

    Aquaporin (AQP) water channels are expressed in the eye at sites of aqueous fluid production and outflow: AQP1 and AQP4 in nonpigmented ciliary epithelium, and AQP1 in trabecular meshwork endothelium. Novel methods were developed to compare aqueous fluid dynamics in wild-type mice versus mice lacking AQP1 and/or AQP4. Aqueous fluid production was measured by in vivo confocal microscopy after transcorneal iontophoretic introduction of fluorescein. Intraocular pressure (IOP), outflow, and anterior chamber compliance were determined from pressure measurements in response to fluid infusions using micropipettes. Aqueous fluid volume and [Cl(-)] were assayed in samples withdrawn by micropipettes. In wild-type mice (CD1 genetic background, age 4-6 wk), IOP was 16.0 +/- 0.4 mmHg (SE), aqueous fluid volume 7.2 +/- 0.3 microl, fluid production 3.6 +/- 0.2 microl/h, fluid outflow 0.36 +/- 0.06 microl/h/mmHg, and compliance 0.036 +/- 0.006 microl/mmHg. IOP was significantly decreased by up to 1.8 mmHg (P < 0.002) and fluid production by up to 0.9 microl/h in age/litter-matched mice lacking AQP1 and/or AQP4 (outbred CD1 and inbred C57/bl6 genetic backgrounds). However, AQP deletion did not significantly affect outflow, [Cl(-)], volume, or compliance. These results provide evidence for the involvement of AQPs in intraocular pressure regulation by facilitating aqueous fluid secretion across the ciliary epithelium. AQP inhibition may thus provide a novel approach for the treatment of elevated IOP.

  11. Short-Term Moderately Elevated Intraocular Pressure Is Associated With Elevated Scotopic Electroretinogram Responses

    PubMed Central

    Choh, Vivian; Gurdita, Akshay; Tan, Bingyao; Prasad, Ratna C.; Bizheva, Kostadinka; Joos, Karen M.

    2016-01-01

    Purpose Moderately elevated intraocular pressure (IOP) is a risk factor for open-angle glaucoma. Some patients suffer glaucoma despite clinically measured normal IOPs. Fluctuations in IOP may have a significant role since IOPs are higher during sleep and inversion activities. Controlled transient elevations of IOPs in rats over time lead to optic nerve structural changes that are similar to the early changes observed in constant chronic models of glaucoma. Because early intervention decreases glaucoma progression, this study was done to determine if early physiological changes to the retina could be detected with noninvasive electrophysiological and optical imaging tests during moderately elevated IOP. Methods Intraocular pressures were raised to moderately high levels (35 mm Hg) in one eye of Sprague-Dawley rats while the other (control) eye was untreated. One group of rats underwent scotopic threshold response (STR) and electroretinogram (ERG) testing, while another 3 groups underwent optical coherence tomography (OCT) imaging, Western blot, or histologic evaluation. Results The amplitudes of the STR and ERG responses in eyes with moderately elevated IOPs were enhanced compared to the values before IOP elevation, and compared to untreated contralateral eyes. Structural changes to the optic nerve also occurred during IOP elevation. Conclusions Although ischemic IOP elevations are well-known to globally reduce components of the scotopic ERG, acute elevation in rats to levels often observed in untreated glaucoma patients caused an increase in these parameters. Further exploration of these phenomena may be helpful in better understanding the mechanisms mediating early retinal changes during fluctuating or chronically elevated IOP. PMID:27100161

  12. UV solid state laser ablation of intraocular lenses

    NASA Astrophysics Data System (ADS)

    Apostolopoulos, A.; Lagiou, D. P.; Evangelatos, Ch.; Spyratou, E.; Bacharis, C.; Makropoulou, M.; Serafetinides, A. A.

    2013-06-01

    Commercially available intraocular lenses (IOLs) are manufactured from silicone and acrylic, both rigid (e.g. PMMA) and foldable (hydrophobic or hydrophilic acrylic biomaterials), behaving different mechanical and optical properties. Recently, the use of apodizing technology to design new diffractive-refractive multifocals improved the refractive outcome of these intraocular lenses, providing good distant and near vision. There is also a major ongoing effort to refine laser refractive surgery to correct other defects besides conventional refractive errors. Using phakic IOLs to treat high myopia potentially provides better predictability and optical quality than corneal-based refractive surgery. The aim of this work was to investigate the effect of laser ablation on IOL surface shaping, by drilling circular arrays of holes, with a homemade motorized rotation stage, and scattered holes on the polymer surface. In material science, the most popular lasers used for polymer machining are the UV lasers, and, therefore, we tried in this work the 3rd and the 5th harmonic of a Q-switched Nd:YAG laser (λ=355 nm and λ=213 nm respectively). The morphology of the ablated IOL surface was examined with a scanning electron microscope (SEM, Fei - Innova Nanoscope) at various laser parameters. Quantitative measurements were performed with a contact profilometer (Dektak-150), in which a mechanical stylus scanned across the surface of gold-coated IOLs (after SEM imaging) to measure variations in surface height and, finally, the ablation rates were also mathematically simulated for depicting the possible laser ablation mechanism(s). The experimental results and the theoretical modelling of UV laser interaction with polymeric IOLs are discussed in relation with the physical (optical, mechanical and thermal) properties of the material, in addition to laser radiation parameters (laser energy fluence, number of pulses). The qualitative aspects of laser ablation at λ=213 nm reveal a

  13. The Safety, Pharmacokinetics, and Efficacy of Intraocular Celecoxib

    PubMed Central

    Kim, Stephen J.; Toma, Hassanain; Shah, Rohan; Kompella, Uday B.; Vooturi, Sunil K.; Sheng, Jinsong

    2014-01-01

    Purpose. To determine safety, pharmacokinetics, and anti-inflammatory effects of intraocular celecoxib. Methods. The right eye of animals was injected with 1.5, 3, or 6 mg celecoxib prepared in dimethyl sulfoxide (DMSO). Left eyes served as controls and received 0.1 mL DMSO. Electroretinograms (ERG) were obtained at baseline and at 1, 4, and 12 weeks, and eyes were enucleated afterward for histopathologic analysis. For pharmacokinetics, 3 mg celecoxib was injected, and vitreous and retina/choroid drug levels were then analyzed at specific time points. For efficacy, 1 μg lipopolysaccharide was injected to induce inflammation; the right eye was then injected with 3 mg celecoxib (six eyes) or 2 mg triamcinolone acetonide (six eyes) and the left eye with saline. Twenty-four hours later, aqueous fluid was removed, and total leukocyte concentration and prostaglandin E2 (PGE2) concentration were determined. Results. Histologic and ERG studies demonstrated no signs of retinal or optic nerve toxicity. After a single 3-mg injection, vitreous (0.06 μg/mL) and retina/choroid (132.31 μg/g) celecoxib concentrations at 8 weeks exceeded median inhibitory concentration. Treatment with celecoxib and triamcinolone significantly reduced total leukocyte count by 40% (P = 0.02) and 31% (P = 0.01), respectively. Reduction in PGE2 levels paralleled reduction in leukocyte counts (P < 0.05). There was no increase in intraocular pressure, but cataract formation was observed at higher concentrations. Conclusions. Intraocular injection of celecoxib appeared to be nontoxic and demonstrated excellent penetration into the retina/choroid and sustained drug levels out to 8 weeks. Celecoxib demonstrated potent anti-inflammatory effects, but there was an association with cataract formation at higher doses. PMID:24458149

  14. Method for in vitro assessment of straylight from intraocular lenses

    PubMed Central

    Łabuz, Grzegorz; Vargas-Martín, Fernando; van den Berg, Thomas J.T.P.; López-Gil, Norberto

    2015-01-01

    Ocular straylight has been measured by means of psychophysical methods over the years. This approach gives a functional parameter yielding a straight comparison with optically defined light scattering, and the point-spread-function. This is of particular importance when the effect of intraocular lenses (IOLs) on postoperative straylight is sought. An optical system for straylight measurements of IOLs was adapted to a commercial device (C-Quant, Oculus), which employs such psychophysical method. The proposed modifications were validated using light-scattering filters and some sample IOLs. The measurements were performed by 3 observers to prove that results are independent from straylight of the eye. Other applications will be discussed. PMID:26601008

  15. Spontaneous Late Intraocular Lens and Capsule Tension Ring Dislocation

    PubMed Central

    Koçak Altıntaş, Ayşe Gül; Omay, Aslıhan Esra; Çelik, Selda

    2017-01-01

    In this report, three cases with pseudoexfoliation (PEX) and advanced age with spontaneous intraocular lens (IOL) and capsule tension ring (CTR) dislocation were presented. All of our cases experienced progressive vision loss without an episode of strenuous physical activity, trauma, or any other ocular disease. Spontaneous dislocation was observed 2.5 to 8 years after uneventful phacosurgery. Each patient underwent complete IOL and CTR removal combined with anterior chamber IOL implantation. No complications were noticed during follow-up. As a result, capsule tension ring does not prevent late IOL dislocation after uncomplicated phacosurgery in the presence of PEX. Therefore, close follow-up is essential for patients with PEX.

  16. Unilateral Crystalline Vitreoretinopathy: A Rare Entity Associated with Intraocular Inflammation

    PubMed Central

    Harshey, Kaustubh B.; Srinivasan, Karthik; Rengappa, Ramakrishnan; Ramasamy, Kim

    2015-01-01

    A 31-year-old Indian male presented with floaters and diminution of vision in the right eye. Ocular examination showed features of old anterior uveitis with posterior subcapsular cataract and fine, refractile crystals in the vitreous cavity and on the retinal surface. A thorough workup for all known causes of crystalline retinopathy was inconclusive. Unilateral crystalline retinopathy has been sparingly reported. This is the first report of unilateral, crystalline vitreoretinopathy in the absence of any demonstrable and known cause for intraocular crystals. PMID:26688764

  17. Retro iris suture fixation of a rigid intraocular lens.

    PubMed

    Haripriya, Aravind; Sharma, Sankalp S

    2016-11-01

    We present an iris suture fixation technique for a rigid poly(methyl methacrylate) (PMMA) intraocular lens (IOL). A 10-0 polypropylene suture on a long curved needle is used to preplace 2 iris suture bites 180 degrees apart. The suture loops below the iris are retracted through the main scleral tunnel using a Kuglen hook and a McPherson forceps. The 2 suture loops are twirled twice around the corresponding haptics of a standard 3-piece PMMA IOL, and the IOL is placed in the sulcus. After it is confirmed that the loop surrounds the haptic, the suture knot is tied to secure the IOL to the iris.

  18. First reported case of intraocular Gnathostoma spinigerum in Cambodia.

    PubMed

    Hem, S; Tarantola, A; Chheang, R; Nop, P; Kerléguer, A

    2015-12-01

    A live intraocular nematode was identified from a 37 year-old man presented with iritis, pain, redness, lacrimation, swelling, vision loss and intermittent blindness during many hours per day of the left eye. By using slit lamp examination, a worm was removed from iris in an ophthalmology outpatient department setting and sent to the Medical Microbiology Laboratory, Institut Pasteur du Cambodge. Gnathostoma spinigerum was identified, based on its typical morphology via microscopic examination. Based on our diagnosis, the patient was treated by oral albendazole and responded well to this therapy.

  19. Is 24-hour Intraocular Pressure Monitoring Necessary in Glaucoma?

    PubMed Central

    Mansouri, Kaweh; Weinreb, Robert N.; Medeiros, Felipe A.

    2013-01-01

    Although intraocular pressure (IOP) is the only treatable risk factor for glaucoma, its 24-hour behavior is poorly understood. Conflicting information is available in the literature with regard to the importance and predictive value of IOP peaks and fluctuations on the risk of glaucoma development and progression. This may be secondary to lack of prospective studies designed to address this issue. This article critically reviews the current evidence for the importance of 24-h IOP measurements in glaucoma and discusses shortcomings of current methods to assess 24-h IOP data, drawing attention to new developments in this field. PMID:23697618

  20. Hypotonous malignant glaucoma: aqueous misdirection with low intraocular pressure.

    PubMed

    Burgansky-Eliash, Zvia; Ishikawa, Hiroshi; Schuman, Joel S

    2008-01-01

    Two patients who underwent trabeculectomy and postoperatively manifested axially shallow anterior chamber associated with hypotony but without choroidal effusion are described. The first patient was treated conservatively with topical cycloplegics. The second patient was treated with pars plana anterior vitrectomy. The interventions resulted in deepening of the anterior chamber and posterior rotation of the ciliary body to a natural position as observed by ultrasound biomicroscopy. Intraocular pressure remained low in both cases. These cases demonstrate that hypotony and axial shallowing of the anterior chamber after trabeculectomy can result in a malignant glaucoma-like appearance.

  1. Pigment dispersion syndrome associated with intraocular lens implantation: a new surgical technique

    PubMed Central

    Jordana, M Isabel Canut; Formigó, Daniel Pérez; González, Rodrigo Abreu; Reus, Jeroni Nadal

    2010-01-01

    Aims We report the case of a myopic patient who, after intraocular lens transplant in the posterior chamber, suffered elevated intraocular pressure due to pigment dispersion, with recurrent episodes of blurred vision. The patient was treated with a new surgical technique that can avoid potential iridolenticular contact. Methods Complete ophthalmologic examination and optical coherence tomography (OCT) of the anterior segment were performed. Results Contact between the pigmentary epithelium and the iris with an intraocular lens was revealed by utrasound biomicroscopy and OCT. In this case, Nd:YAG laser iridotomy and laser iridoplasty were not effective for iridolenticular separation and control of the pigment dispersion. We propose a new technique: stitches on the surface of the iris to obtain good iridolenticular separation and good intraocular pressure control. Conclusion Stitches on the iris surface should be considered as optional therapy in pigmentary glaucoma secondary to intraocular lens implantation. This surgical technique can avoid potential iridolenticular contacts more definitively. PMID:21151331

  2. RGD Surface Functionalization of the Hydrophilic Acrylic Intraocular Lens Material to Control Posterior Capsular Opacification

    PubMed Central

    Huang, Yi-Shiang; Bertrand, Virginie; Bozukova, Dimitriya; Pagnoulle, Christophe; Labrugère, Christine; De Pauw, Edwin; De Pauw-Gillet, Marie-Claire; Durrieu, Marie-Christine

    2014-01-01

    Posterior Capsular Opacification (PCO) is the capsule fibrosis developed on implanted IntraOcular Lens (IOL) by the de-differentiation of Lens Epithelial Cells (LECs) undergoing Epithelial Mesenchymal Transition (EMT). Literature has shown that the incidence of PCO is multifactorial including the patient's age or disease, surgical technique, and IOL design and material. Reports comparing hydrophilic and hydrophobic acrylic IOLs have shown that the former has more severe PCO. On the other hand, we have previously demonstrated that the adhesion of LECs is favored on hydrophobic compared to hydrophilic materials. By combining these two facts and contemporary knowledge in PCO development via the EMT pathway, we propose a biomimetically inspired strategy to promote LEC adhesion without de-differentiation to reduce the risk of PCO development. By surface grafting of a cell adhesion molecule (RGD peptide) onto the conventional hydrophilic acrylic IOL material, the surface-functionalized IOL can be used to reconstitute a capsule-LEC-IOL sandwich structure, which has been considered to prevent PCO formation in literature. Our results show that the innovative biomaterial improves LEC adhesion, while also exhibiting similar optical (light transmittance, optical bench) and mechanical (haptic compression force, IOL injection force) properties compared to the starting material. In addition, compared to the hydrophobic IOL material, our bioactive biomaterial exhibits similar abilities in LEC adhesion, morphology maintenance, and EMT biomarker expression, which is the crucial pathway to induce PCO. The in vitro assays suggest that this biomaterial has the potential to reduce the risk factor of PCO development. PMID:25501012

  3. [Opacification of an intraocular lens: calcification of hydrophilic intraocular lenses after gas tamponade of the anterior chamber].

    PubMed

    Schmidinger, G; Pemp, B; Werner, L

    2013-11-01

    A patient with endothelial dystrophy was treated with Descemet stripping automated endothelial keratoplasty (DSAEK) combined with cataract extraction and implantation of a hydrophilic intraocular lens (IOL, Lentis-L312, Oculentis) but visual acuity dropped from 0.15 logMAR to 0.52 logMAR 18 months later due to calcification of the IOL. With new methods of lamellar corneal transplantation being used more frequently the number of necessary anterior chamber tamponades with air/gas are increasing. In cataract cases in which a gas tamponade and transplantation might be necessary later on (cornea guttata), hydrophilic IOLs should be avoided.

  4. Visual Performance after Bilateral Implantation of a Four-Haptic Diffractive Toric Multifocal Intraocular Lens in High Myopes

    PubMed Central

    Chan, Vincent K. C.

    2016-01-01

    Background. The vision with diffractive toric multifocal intraocular lenses after cataract surgery in long eyes has not been studied previously. Objectives. To report visual performance after bilateral implantation of a diffractive toric multifocal intraocular lens in high myopes. Methods. Prospective, observational case series to include patients with axial length of ≥26 mm and corneal astigmatism of >1 dioptre who underwent bilateral AT LISA 909M implantation. Postoperative examinations included photopic and mesopic distance, intermediate, and near visual acuity; photopic contrast sensitivity; visual symptoms (0–5); satisfaction (1–5); and spectacle independence rate. Results. Twenty-eight eyes (14 patients) were included. Postoperatively, mean photopic monocular uncorrected distance, intermediate, and near visual acuities (logMAR) were 0.12 ± 0.20 (standard deviation), 0.24 ± 0.16, and 0.29 ± 0.21, respectively. Corresponding binocular values were −0.01 ± 0.14, 0.13 ± 0.12, and 0.20 ± 0.19, respectively. One eye (4%) had one-line loss in vision. Under mesopic condition, intermediate vision and near vision decreased significantly (all P ≤ 0.001). Contrast sensitivity at all spatial frequencies did not improve significantly under binocular condition (all P > 0.05). Median scores for halos, night glare, starbursts, and satisfaction were 0.50, 0.00, 0.00, and 4.25, respectively. Ten patients (71%) reported complete spectacle independence. Conclusions. Bilateral implantation of the intraocular lens in high myopes appeared to be safe and achieved good visual performance and high satisfaction. PMID:27563460

  5. Regulation of intraocular pressure in mice: structural analysis of dopaminergic and serotonergic systems in response to cabergoline.

    PubMed

    Platania, Chiara Bianca Maria; Leggio, Gian Marco; Drago, Filippo; Salomone, Salvatore; Bucolo, Claudio

    2013-11-01

    Elevated intraocular pressure (IOP) is the main recognized risk factor of glaucoma. To investigate the contribution of dopaminergic and serotonergic systems in IOP regulation, we used cabergoline, a mixed dopamine and serotonin agonist, in C57BL/6J WT and dopamine D₃ receptor knock-out (D₃R⁻/⁻) mice with normal eye pressure or steroid-induced ocular hypertension. Furthermore, we studied the structural basis of the cabergoline-mediated activation of the dopaminergic and serotonergic systems by molecular modeling. Topical application of cabergoline, significantly decreased, in a dose-dependent manner, the intraocular pressure in WT mice, both in an ocular normotensive group (-9, -5 and -2 mmHg with 5%, 1%, and 0.1%, respectively) and an ocular hypertensive group, with a prolonged effect in this latter group. No change of intraocular pressure was observed after topical application of cabergoline in D₃R⁻/⁻ mice. We modeled and optimized, with molecular dynamics, structures of hD₃, h5HT(1A) and h5HT(2A-C) receptors; thereafter we carried out molecular docking of cabergoline. Docking revealed that binding of cabergoline into D₃ and 5HT(1A) receptors is associated with a better desolvation energy in comparison to 5HT(2A-C) binding. In conclusion, the present study support the hypothesis that dopaminergic system is pivotal to regulate IOP and that D₃R represents an intriguing target in the treatment of glaucoma. Furthermore, the structure-based computational approach adopted in this study is able to build and refine structure models of homologous dopaminergic and serotonergic receptors that may be of interest for structure-based drug discovery of ligands, with dopaminergic selectivity or with multi-pharmacological profile, potentially useful to treat optic neuropathies.

  6. Intraocular beta-radiation for proliferative vitreo-retinopathy.

    PubMed

    Shah, Paritosh; Kon, Chee; Rassam, Sal

    2014-04-01

    Proliferative vitreoretinopathy (PVR) is the most common cause of failure in retinal detachment surgery. PVR is a result of an enhanced healing process. Various surgical and pharmacological methods have failed to provide a definite solution to the problem. Radiation has since long been shown to be effective in similar situations like keloids, pterygia, and post trabeculectomy. Externally delivered radiation has also been tried in PVR, but with limited success. We propose that treatment with intraocularly delivered beta-radiation is a viable method to try and reduce the incidence of PVR after retinal detachment. This can improve the safety of the treatment, reduce potential side effects to surrounding tissues and help achieve a targeted treatment. However, the treatment was limited by the absence of a practical method for intraocular delivery of radiation. This is now possible, as we now have a method which has been shown to be safe in the CABERNET trial. If this can be proved, then it will be an important step towards treating PVR and hence reducing blindness after retinal detachment.

  7. Intra-ocular pressure normalization technique and equipment

    NASA Technical Reports Server (NTRS)

    Mcgannon, W. J. (Inventor)

    1980-01-01

    A method and apparatus for safely reducing abnormally high intraocular pressure in an eye during a predetermined time interval is presented. This allows maintenance of normal intraocular pressure during glaucoma surgery. According to the invention, a pressure regulator of the spring biased diaphragm type is provided with additional bias by a column of liquid. The height of the column of liquid is selected such that the pressure at a hypodermic needle connected to the output of the pressure regulator is equal to the measured pressure of the eye. The hypodermic needle can then be safely inserted into the anterior chamber of the eye. Liquid is then bled out of the column to reduce the bias on the diaphragm of the pressure regulator and, consequently, the output pressure of the regulator. This lowering pressure of the regulator also occurs in the eye by means of a small second bleed path provided between the pressure regulator and the hypodermic needle. Alternately, a second hypodermic needle may be inserted into the eye to provide a controlled leak off path for excessive pressure and clouded fluid from the anterior chamber.

  8. Intraocular epiretinal prosthesis to restore vision in blind humans.

    PubMed

    Mokwa, W; Goertz, M; Koch, C; Krisch, I; Trieu, H K; Walter, P

    2008-01-01

    Visual sensations in blind patients suffering from retinal degenerations may be restored by electrical stimulation of retinal neurons using implantable microelectrode arrays. The EPI-RET-3 project was initiated to evaluate a wireless intraocular retinal implant system for human use in terms of safety and efficiency. The implant is a remotely controlled fully intraocular prosthesis consisting of a receiver and a stimulator module. The stimulator is placed onto the retina's surface. Data and energy are transmitted via an inductive link from outside the eye to the implant. The EPI-RET-3 device was implanted into six legally blind patients with Retinitis Pigmentosa (RP) for a period of four weeks. The surgery was performed without complications. The implants were activated on days 7, 14 and 27 after implantation. All patients reported visual sensations such as dots, arcs, or lines of different colours and intensities. The required stimulation thresholds were found to be very low. Implantation of the wireless EPI-RET-3 device is safe and the system is suitable to elicit visual sensations in blind RP patients. Major problems in the design and fabrication of a prosthesis for artificial vision could be solved in this approach.

  9. MEASUREMENT OF INTRAOCULAR PRESSURE IN THE DOMESTIC PIGEON (COLUMBIA LIVIA).

    PubMed

    Ansari Mood, Maneli; Rajaei, Seyed Mehdi; Hashemi, Seyed Sohail Ghazanfari; Williams, David L

    2016-09-01

    The purpose of this study was to establish intraocular pressure values in clinically normal pigeons. One hundred (52 male and 48 female) healthy pigeons ( Columbia livia ) of six different breeds, ranging in age from 20 to 51 mo were used in the study. Pigeons were gently physically restrained in a dorsoventral position without any pressure or extension to the head and neck. A rebound tonometer with a disposable probe was held horizontally and 4-5 mm from the central corneal surface. Calibration of the device was set to "P." Overall, the mean ± SD intraocular pressure values of all eyes were 6.1 ± 0.9 mmHg (ranging from 3 to 9 mmHg). Mean ± SD values for left and right eyes were 6.1 ± 1.0 and 6.0 ± 1.2 mmHg, respectively. There was no statistically significant difference in IOP between the left eye and right eye or between males and females (P = 0.49; P = 0.74). Analysis of variance revealed that there were no significant differences in the IOP between the breeds (P = 0.22).

  10. Posterior Iris Fixated Intraocular Lens for Pediatric Traumatic Cataract

    PubMed Central

    Kavitha, V.; Balasubramanian, Preethi; Heralgi, Mallikarjun M.

    2016-01-01

    Purpose: To evaluate the postoperative visual outcomes and complications of posterior iris fixated intraocular lens (IFIOL) implantation for pediatric traumatic cataract. Methods: A retrospective clinical audit was performed of all the pediatric traumatic cataract patients who underwent lens removal and iris fixated lens implantation due to inadequate capsular support with or without corneal tear repair between January 2009 and December 2013. Data were collected and analyzed on the preoperative and postoperative visual outcomes and complications. Results: Twenty-five children (25 eyes; 21 males and 4 females) were enrolled with the mean age of 11 ± 4.0 years. There were 72% of eyes that underwent primary cataract removal with IFIOL implantation. Twenty-eight percent of eyes underwent corneal tear repair prior to intraocular lens (IOL) implantation. Preoperative best corrected visual acuity (BCVA) was hand motion in 32% eyes, counting fingers in 24%, and perception of light in 44%. Postoperative BCVA of 0-0.2 logarithm of minimum angle of resolution was reported in the 64% of eyes. One eye developed secondary glaucoma, one eye underwent re-enclavation, and none developed retinal complications. Conclusion: Posterior IFIOL implantation resulted in an improved visual outcome, low incidence of postoperative complications, and is a good alternative to other IOL, in the cases of pediatric traumatic cataract without adequate capsular support. PMID:27162456

  11. An examination of the hypothesis that intraocular pressure elevation episodes can have prognostic significance in glaucoma suspects.

    PubMed

    McMonnies, Charles

    2015-01-01

    The efficacy of intraocular pressure reduction in retarding the progression of glaucoma has been demonstrated. This review examines the potential for prognostic advantage for glaucoma suspects in reducing their optic nerve head exposure to elevated intraocular pressure associated with activities which have been shown to elevate intraocular pressure. In this observational study, patients examined at the Centre for Eye Health (University of New South Wales) with a diagnosis of glaucoma suspect were surveyed to determine their histories for participation in activities which are known to elevate intraocular pressure. The evidence regarding the pathological significance of these sources of elevation in susceptible patients was examined. Apart from the universality of sleep-related intraocular pressure elevations, the histories from 183 confirmed glaucoma suspects indicate a wide range and variation in frequency of participation in other intraocular pressure elevating activities. A reduction in exposure to elevated intraocular pressure may improve the prognosis for glaucoma suspects. Additional patient specific assessment of the results of this screening could provide an indication of the degree (frequency, intensity level and duration) of exposure to elevated intraocular pressure. Such information may provide the basis for improving a patient's prognosis by helping them to identify opportunities to reduce such exposure to elevated intraocular pressure. Any benefit of reduction of such exposure appears likely to be greater if activities which elevate intraocular pressure are of long duration, occur frequently, occur over a long period of time, and/or involve high levels of intraocular pressure elevation.

  12. Coculture with intraocular lens material-activated macrophages induces an inflammatory phenotype in lens epithelial cells.

    PubMed

    Pintwala, Robert; Postnikoff, Cameron; Molladavoodi, Sara; Gorbet, Maud

    2015-03-01

    Cataracts are the leading cause of blindness worldwide, requiring surgical implantation of an intraocular lens. Despite evidence of leukocyte ingress into the postoperative lens, few studies have investigated the leukocyte response to intraocular lens materials. A novel coculture model was developed to examine macrophage activation by hydrophilic acrylic (poly(2-hydroxyethyl methacrylate)) and hydrophobic acrylic (polymethylmethacrylate) commercial intraocular lens. The human monocytic cell line THP-1 was differentiated into macrophages and cocultured with human lens epithelial cell line (HLE-B3) with or without an intraocular lens for one, two, four, or six days. Using flow cytometry and confocal microscopy, expression of the macrophage activation marker CD54 (intercellular adhesion molecule-1) and production of reactive oxygen species via the fluorogenic probe 2',7'-dichlorodihydrofluorescein diacetate were examined in macrophages. α-Smooth muscle actin, a transdifferentiation marker, was characterized in lens epithelial cells. The poly(2-hydroxyethyl methacrylate) intraocular lens prevented adhesion but induced significant macrophage activation (p < 0.03) versus control (no intraocular lens), while the polymethylmethacrylate intraocular lens enabled adhesion and multinucleated fusion, but induced no significant activation. Coculture with either intraocular lens increased reactive oxygen species production in macrophages after one day (p < 0.03) and increased expression of α-smooth muscle actin in HLE B-3 after six days, although only poly(2-hydroxyethyl methacrylate) induced a significant difference versus control (p < 0.01). Our results imply that-contrary to prior uveal biocompatibility understanding-macrophage adherence is not necessary for a strong inflammatory response to an intraocular lens, with hydrophilic surfaces inducing higher activation than hydrophobic surfaces. These findings provide a new method of inquiry into uveal

  13. Optical quality of toric intraocular lens implantation in cataract surgery

    PubMed Central

    Xiao, Xian-Wen; Hao, Jing; Zhang, Hong; Tian, Fang

    2015-01-01

    AIM To analyze the optical quality after implantation of toric intraocular lens with optical quality analysis system. METHODS Fifty-two eyes of forty-four patients with regular corneal astigmatism of at least 1.00 D underwent implantation of AcrySof toric intraocular lens, including T3 group 19 eyes, T4 group 18 eyes, T5 group 10 eyes, T6 group 5 eyes. Main outcomes evaluated at 3mo of follow-up, included uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), residual refractive cylinder and intraocular lens (IOL) axis rotation. Objective optical quality were measured using optical quality analysis system (OQAS II®, Visiometrics, Spain), included the cutoff frequency of modulation transfer function (MTFcutoff), objective scattering index (OSI), Strehl ratio, optical quality analysis system value (OV) 100%, OV 20% and OV 9% [the optical quality analysis system (OQAS) values at contrasts of 100%, 20%, and 9%]. RESULTS At 3mo postoperative, the mean UDVA and CDVA was 0.18±0.11 and 0.07±0.08 logMAR; the mean residual refractive cylinder was 0.50±0.29 D; the mean toric IOL axis rotation was 3.62±1.76 degrees, the mean MTFcutoff, OSI, Strehl ratio, OV 100%, OV 20% and OV 9% were 22.862±5.584, 1.80±0.84, 0.155±0.038, 0.76±0.18, 0.77±0.19 and 0.78±0.21. The values of UDVA, CDVA, IOL axis rotation, MTFcutoff, OSI, Strehl ratio, OV100%, OV20% and OV9% depending on the power of the cylinder of the implantation were not significantly different (P>0.05), except the residual refractive cylinder (P<0.05). CONCLUSION The optical quality analysis system was useful for characterizing the optical quality of AcrySof toric IOL implantation. Implantation of an AcrySof toric IOL is an effective and safe method to correct corneal astigmatism during cataract surgery. PMID:25709910

  14. Ghost cell glaucoma following sutureless scleral-fixated posterior chamber intraocular lens placement.

    PubMed

    Thompson, Jordan M; Chang, Jonathan S; Bermudez-Magner, J Antonio; Dubovy, Sander R

    2015-01-01

    Secondary intraocular lens (IOL) placement in the absence of a capsular bag may result in several complications. The authors report the clinicopathologic features of a case of ghost cell glaucoma after the placement of a sutureless posterior chamber IOL. A 47-year-old male presented with a dislocated IOL and underwent lens exchange using a sutureless scleral-fixation technique. Over the following year, the patient developed recurrent vitreous hemorrhages and elevated intraocular pressure despite medical therapy, and an aqueous specimen disclosed ghost cells. Although uncommon, mechanical contact between the iris and a secondary IOL may produce persistent vitreous hemorrhage and elevated intraocular pressures with the formation of ghost cells.

  15. Ocular onchocerciasis in the Yanomami communities from Brazilian Amazon: effects on intraocular pressure.

    PubMed

    Herzog-Neto, Guilherme; Jaegger, Karen; Nascimento, Erika S do; Marchon-Silva, Verônica; Banic, Dalma M; Maia-Herzog, Marilza

    2014-01-01

    To determine the influence of onchocercal eye disease on the intraocular pressure of the Yanomami Tribe Aratha-ú of Roraima State, Brazil, considered endemic for onchocerciasis, a total of 86 patients were submitted to an ophthalmologic exam that included external examination, slit lamp examination, intraocular pressure measurement, and a fundus ophthalmoscope examination. A high prevalence of onchocerciasis-related eye lesions was encountered in 68.6% of the patients. Punctate keratitis and microfilariae in the anterior chamber were found in ∼28%. The mean of intraocular eye pressure found was 10.47 mm of Hg.

  16. Untreated Active Tuberculosis in Pregnancy with Intraocular Dissemination: A Case Report and Review of the Literature.

    PubMed

    Rezai, Shadi; LoBue, Stephen; Adams, Daniel; Oladipo, Yewande; Posso, Ramses; Mapp, Tiffany; Santiago, Crystal; Jain, Manisha; Marino, William D; Henderson, Cassandra E

    2015-01-01

    Background. Tuberculosis (TB) is a disease that affects hundreds of millions of people across the world. However, the incidence in developed countries has decreased over the past decades causing physicians to become unfamiliar with its unspecific symptoms. Pregnant individuals are especially difficult because many symptoms of active TB can mimic normal physiological changes of pregnancy. We present a case report of a 26-year-old multiparous woman, G4P3003, at 38-week gestation with a history of positive PPD who emigrated from Ghana 6 years ago. She came to the hospital with an initial complaint of suprapubic pain, pressure, and possible leakage of amniotic fluid for the past week. Patient also complained of a productive cough for the past 3 to 4 months with a decrease in vision occurring with the start of pregnancy. Visual acuity was worse than 20/200 in both eyes. Definitive diagnosis of active TB was delayed due to patient refusal of chest X-ray. Fortunately, delay in diagnosis was minimized since patient delivered within 24 hours of admission. Active TB was confirmed with intraocular dissemination. Patient had optic atrophy OS (left eye) and papillitis, choroiditis, and uveitis OD (right eye) due to TB infiltration. Fetus was asymptomatic and anti-TB therapy was started for both patients.

  17. Untreated Active Tuberculosis in Pregnancy with Intraocular Dissemination: A Case Report and Review of the Literature

    PubMed Central

    LoBue, Stephen; Adams, Daniel; Oladipo, Yewande; Posso, Ramses; Mapp, Tiffany; Santiago, Crystal; Jain, Manisha; Marino, William D.; Henderson, Cassandra E.

    2015-01-01

    Background. Tuberculosis (TB) is a disease that affects hundreds of millions of people across the world. However, the incidence in developed countries has decreased over the past decades causing physicians to become unfamiliar with its unspecific symptoms. Pregnant individuals are especially difficult because many symptoms of active TB can mimic normal physiological changes of pregnancy. We present a case report of a 26-year-old multiparous woman, G4P3003, at 38-week gestation with a history of positive PPD who emigrated from Ghana 6 years ago. She came to the hospital with an initial complaint of suprapubic pain, pressure, and possible leakage of amniotic fluid for the past week. Patient also complained of a productive cough for the past 3 to 4 months with a decrease in vision occurring with the start of pregnancy. Visual acuity was worse than 20/200 in both eyes. Definitive diagnosis of active TB was delayed due to patient refusal of chest X-ray. Fortunately, delay in diagnosis was minimized since patient delivered within 24 hours of admission. Active TB was confirmed with intraocular dissemination. Patient had optic atrophy OS (left eye) and papillitis, choroiditis, and uveitis OD (right eye) due to TB infiltration. Fetus was asymptomatic and anti-TB therapy was started for both patients. PMID:26693374

  18. Effect of incision types for Artisan phakic intraocular lens implantation on ocular higher order aberrations

    PubMed Central

    Park, Young Min; Choi, Bong Joon; Lee, Jong Soo

    2016-01-01

    AIM To evaluate the effect of incision types for Artisan phakic intraocular lens (PIOL) implantation on ocular higher-order aberrations (HOAs). METHODS A retrospective review was conducted of the patients who had undergone Artisan PIOL implantation for the correction of myopia and followed up for at least 6mo. Patients are classified into 2 groups considering the incision type: cornea group with patients undergone clear corneal incision; sclera group with patients undergone sclera tunnel incision. All patients with postoperative astigmatism of under 1 diopter (D) were included to minimize the effect of residual astigmatism on postoperative HOAs. Visual acuity, special equivalents, astigmatism, predictability (±1 D from target refraction), HOAs (coma, trefoil, spherical aberration), and corneal endothelial counts were analyzed preoperatively and 6mo postoperatively. RESULTS At the postoperative 6mo, all patients of both groups achieved uncorrected visual acuity of 16/20 or better, and significantly decreased the spherical equivalents compared with preoperative values. The predictability of refractive correction was 96% in the former, and 94% in the latter. Unlike the sclera group, preoperative astigmatism decreased significantly in cornea group at postoperative 6mo. The HOAs increased significantly at postoperative 6mo compared to the preoperative values in both groups, and the root mean square (RMS) total and trefoil wavefront aberration of cornea group were significantly higher than those of sclera group. CONCLUSION Although corneal incision significantly reduces preexisting astigmatism, the postoperative 6mo of total RMS and trefoil aberration change may deteriorate the visual quality after Artisan PIOL implantation. PMID:28003980

  19. Effects of exercise on intraocular pressure and ocular blood flow: a review.

    PubMed

    Risner, David; Ehrlich, Rita; Kheradiya, Nisha S; Siesky, Brent; McCranor, Lynne; Harris, Alon

    2009-08-01

    Glaucoma is a disease characterized by progressive optic neuropathy resulting in retinal ganglion cell death, which affects approximately 68 million people worldwide. Risk factors include intraocular pressure (IOP), genetics, race, age, and vascular factors. Exercise is known to affect IOP and systemic cardiovascular factors and, therefore, may affect glaucoma pathophysiology. This review discusses the results of articles relevant to glaucoma, IOP, ocular blood flow (OBF), and exercise. Isometric and dynamic exercises have been studied with respect to effects on IOP and OBF. Isometric exercise results in an acute decrease in IOP, which correlates with hypocapnia. Dynamic exercise results in a more pronounced but also short duration decrease in IOP. Physical fitness is associated with lower baseline IOP but diminished acute IOP-lowering response to exercise. Upon cessation of exercise, values return to pretrained levels within 1 month. In glaucoma patients, these IOP-lowering effects are greater than in healthy subjects. In healthy subjects, OBF is unchanged during exercise due to vascular autoregulation. This autoregulation fails at ocular perfusion pressures greater than 70% above baseline. In conclusion exercise in glaucoma patients results in acutely lowered IOP and lower baseline IOP. The effects of exercise on the prevention of glaucoma and glaucomatous progression remain unknown. The role of exercise in glaucoma management should be investigated.

  20. Intraocular Pressure Control after Trabeculectomy, Phacotrabeculectomy and Phacoemulsification in a Hispanic Population

    PubMed Central

    L Jung, Jennifer; Isida-Llerandi, Cristina G; Lazcano-Gomez, Gabriel; SooHoo, Jeffrey R

    2014-01-01

    ABSTRACT Purpose: To compare the efficacy of different surgical strategies for intraocular pressure (IOP) control in Hispanic glaucoma patients with and without visually significant cataracts. Design: Comparative retrospective consecutive case series. Methods: The charts of 153 consecutive patients with primary open angle glaucoma who underwent either trabeculectomy alone (n = 51), phacotrabeculectomy (n = 51), or phacoemulsification alone (n = 51) were reviewed to compare IOP control, the number of glaucoma medications required postoperatively, and the inci dence of surgical complications. Results: Preoperative IOP was 17.5 ± 5.2 mm Hg in the trabe-culectomy group, 15.4 ± 4.5 mm Hg in the phacotrabeculectomy group and 13.9 ± 2.9 mm Hg in the phacoemulsification group (p < 0.001 for all comparisons). Mean IOP reduction from baseline was 4.2 ± 6.9 (24.6%) for the trabeculectomy group, 2.9 ± 5.0 (20.8%) for the phacotrabeculectomy group, and 0.9 ± 3.4 (6.5%) for the phacoemulsification group (p = 0.009). The number of IOP-lowering medications required postoperatively decreased significantly in all three groups (p = 0.001). The rate of early and late postoperative complications was similar between the trabeculectomy and phacotrabeculectomy groups and less for the phacoemulsification group. Conclusion: Trabeculectomy and phacotrabeculectomy are both viable surgical options for managing open angle glau coma. Both resulted in similar rates of success, IOP reduction, decrease in use of IOP-lowering medications and post operative complication rates. Phacoemulsification alone had a lower success rate and greater need for postoperative IOP-lowering medications compared to trabeculectomy alone or phacotrabeculectomy. Phacoemulsification alone may be a reasonable option for patients with visually significant cataract and lower baseline IOP. How to cite this article: Jung JL, Isida-Llerandi CG, Lazcano-Gomez G, SooHoo JR, Kahook MY. Intraocular Pressure Control after

  1. Biomechanics of the sclera and effects on intraocular pressure

    PubMed Central

    Jia, Xu; Yu, Juan; Liao, Sheng-Hui; Duan, Xuan-Chu

    2016-01-01

    Accumulating evidence indicates that glaucoma is a multifactorial neurodegenerative disease characterized by the loss of retinal ganglion cells (RGC), resulting in gradual and progressive permanent loss of vision. Reducing intraocular pressure (IOP) remains the only proven method for preventing and delaying the progression of glaucomatous visual impairment. However, the specific role of IOP in optic nerve injury remains controversial, and little is known about the biomechanical mechanism by which elevated IOP leads to the loss of RGC. Published studies suggest that the biomechanical properties of the sclera and scleral lamina cribrosa determine the biomechanical changes of optic nerve head, and play an important role in the pathologic process of loss of RGC and optic nerve damage. This review focuses on the current understanding of biomechanics of sclera in glaucoma and provides an overview of the possible interactions between the sclera and IOP. Treatments and interventions aimed at the sclera are also discussed. PMID:28003987

  2. Bionic intraocular lens with variable focus and integrated structure

    NASA Astrophysics Data System (ADS)

    Liang, Dan; Wang, Xuan-Yin; Du, Jia-Wei; Xiang, Ke

    2015-10-01

    This paper proposes a bionic accommodating intraocular lens (IOL) for ophthalmic surgery. The designed lens has a solid-liquid mixed integrated structure, which mainly consists of a support ring, elastic membrane, rigid lens, and optical liquid. The lens focus can be adjusted through the deformation of the lens front surface when compressed. The integrated structure of the IOL is presented, as well as a detailed description of the lens materials and fabrication process. Images under different radial pressures are captured, and the lens deformation process, accommodating range, density, and optical property are analyzed. The designed lens achieves a 14.6 D accommodating range under a radial pressure of 51.4 mN and a 0.24 mm alteration of the lens outer radius. The deformation property of the lens matches well with the characteristic of the eye and shows the potential to help patients fully recover their vision accommodation ability after the cataract surgery.

  3. [Combination surgery (ECCE+IOL+TE) and intraocular pressure levels].

    PubMed

    Hornová, J

    1997-08-01

    The authors investigated the effect of a combined operation, ECCE + TE + IOL, on reduction of intraocular pressure (IOP), changes in antiglaucomatous treatment and on vision six months after operation. In 1994 36 eyes were operated, 16 eyes with primary open angle glaucoma (POAG), 8 eyes with angular glaucoma (PACG) and 12 eyes with marked exfoliative syndrome (CG). Six months after operation the IOP declined from 26.4 mm Hg to 13.3 mm Hg (P 0.05), antiglaucomatous treatment was reduced from 2.55 to 1.11 (P 0.05), vision improved by 0.39, i.e. by 2-3 lines of optotypes (P 0.05). 89% of the operated patients have a vision better than 0.5. Comparison of values before and after operation revealed a more marked drop of IOP in CG (P 0.05) than in POAG.

  4. Reversible opacification of a hydrophilic acrylic intraocular lens.

    PubMed

    Park, Choul Yong; Chuck, Roy S

    2012-01-01

    A 56-year-old woman with diabetic retinopathy and chronic myelogenous leukemia had phacoemulsification cataract removal and hydrophilic acrylic intraocular lens (IOL) (Akreos MI-60) implantation in both eyes. One month after surgery, significant IOL opacity and severe cystoid macular edema were observed in both eyes. After bilateral intravitreal injection of bevacizumab (Avastin) to control macular edema, central clearing of the IOL opacity was observed in both eyes. Two months after the injection, the IOL opacity had almost disappeared from both eyes. To our knowledge, this is the first case of early postoperative bilateral IOL opacity in a hydrophilic acrylic IOL cleared after anti-vascular endothelial growth factor (VEGF) intravitreal injection. The role of anti-VEGF therapy in clearing IOL opacification requires further investigation.

  5. Prostaglandin Pathway Gene Therapy for Sustained Reduction of Intraocular Pressure

    PubMed Central

    Barraza, Román A; McLaren, Jay W; Poeschla, Eric M

    2009-01-01

    Cyclooxygenase-2 (COX-2) is a rate-limiting enzyme in prostaglandin (PG) biosynthesis. In the eye, loss of COX-2 expression in aqueous humor–secreting cells has been associated with primary open-angle glaucoma (POAG). Reduction of intraocular pressure (IOP) is the main treatment goal in this disease. We used lentiviral vectors to stably express COX-2 and other PG biosynthesis and response transgenes in the ciliary body epithelium and trabecular meshwork (TM), the ocular suborgans that produce aqueous humor and regulate its outflow, respectively. We show that robust ectopic COX-2 expression and PG production require COX-2 complementary DNA (cDNA) sequence optimization. When COX-2 expression was coupled with a similarly optimized synthetic PGF2α receptor transgene to enable downstream signaling, gene therapy produced substantial and sustained reductions in IOP in a large animal model, the domestic cat. This study provides the first gene therapy for correcting the main cause of glaucoma. PMID:19953083

  6. Shape optimization of an accommodative intra-ocular lens

    NASA Astrophysics Data System (ADS)

    Jouve, François; Hanna, Khalil

    2005-03-01

    Cataract surgery consists in replacing the clouded or opacified crystalline lens by an Intra-Ocular Lens (IOL) having the same mean dioptrical power. Clear vision is then achieved at a given distance and glasses are needed in many situations. A new kind of IOL, potentially accommodative, is proposed. Its design is based on the deep understanding of the accommodation mechanism and on the mathematical modeling and the numerical simulation of the IOL's comportment in vivo. A preliminary version of this IOL is now commercialized by the company HumanOptics under the name '1CU'. In a second phase, shape optimization techniques equipped with strong mechanical and physiological constraints, are used to enhance the IOL performance and build a new design. To cite this article: F. Jouve, K. Hanna, C. R. Mecanique 333 (2005).

  7. Experimental intraocular malignancy: the effect of intracameral perfusion.

    PubMed Central

    Wong, V G; Green, W R; Liu, Y P; Marsden, E R

    1979-01-01

    Transplantable Brown-Pearce carcinoma was adapted successfully in the rabbit anterior chamber. Regression of tumor growth was attained on tri-weekly perfusion of the AC with 10 micromolar of methotrexate. Tumor cyclic nucleotide phosphodiesterase (PDE) and protein activator were found to be markedly depressed during the course of chemotherapy and the PDE cAMP/cGMP ratio was similarly altered. Corroborative light and electron-microscopic studies showed specific alterations of intracellular organelles in relation to MTX and tumor cell death. These findings suggest that metabolic pathways of cyclic nucleotides are important biochemical modulators of neoplastic cells. The method of intraocular perfusion precludes systemic toxic effects and avoids compromising the animals' immunocompetence. Images FIGURE 3 A FIGURE 3 B FIGURE 4 A FIGURE 4 B PMID:232585

  8. Alcaligenes xylosoxidans endophthalmitis following phacoemulsification and intraocular lens implantation.

    PubMed

    Robert, Pierre-Yves; Chainier, Delphine; Garnier, Fabien; Ploy, Marie-Cécile; Parneix, Pierre; Adenis, Jean-Paul; Martin, Christian

    2008-01-01

    Five consecutive cases of endophthalmitis that developed after cataract extraction by a single surgeon using the same operating room during one morning session are described. Following preoperative topical administration of ciprofloxacin, surgery consisted of phacoemulsification with peristaltic pump and fluid venting, polymethylmethacrylate intraocular lens implantation, and corneal suture. No complications occurred during surgery. All five patients developed endophthalmitis caused by infection with Alcaligenes xylosoxidans in less than 24 hours. Pulsed-field gel electrophoresis was used to prove similarity between strains. Bacterial inquiry on contamination of the operating room environment revealed massive colonization of phacoemulsifier irrigation channels by Pseudomonas fluorescens bacteria from an unestablished source. Four of the five patients ultimately recovered visual acuity better than 20/60.

  9. [Laser magnetotherapy after cataract extraction with implantation of intraocular lens].

    PubMed

    Maksimov, V Iu; Zakharova, N V; Maksimova, I S; Golushkov, G A; Evseev, S Iu

    2002-01-01

    Effects of low-intensive laser and alternating magnetic field on the course of the postoperative period were studied in patients with exudative reaction after extracapsular cataract extraction with implantation of intraocular lens (IOL). The results are analyzed for 148 eyes with early exudative reaction after IOL implantation (136 patients aged 42-75 years). The patients were observed for up to 6 months. The treatment efficiency was evaluated by the clinical picture of inflammatory reaction, visual acuity, and results of biochemical analysis of the lacrimal fluid (the ratio of lipid peroxidation products to antioxidants in cell membrane). The course of the postoperative period was more benign and recovery sooner in patients of the main group in comparison with the control.

  10. Bifocal, Electrically Switched Intraocular And Eyeglass Molecular Lenses

    NASA Astrophysics Data System (ADS)

    Kern, Seymour P.

    1986-05-01

    A bifocal electronic molecular lens is described which can be switched between two foci without any grossly visible change in displacement, geometry, temperature or chemical composition. The lens requires very little power to change focus (on the order of tens to hundreds of nanoamps) so that long-term remote operation is anticipated. The principle of operation is based upon electronic control of optical polarization through a birefringent lens. Switching of focus is accomplished by controlling the molecular alignment of a film of liquid crystal molecules and thereby selecting between two orthogonal optical polarizations (P1 and P2). Polarization P1 is associated with focal point S1 and P2 is associated with focal point S2 through the birefringent lens. A number of useful new products are made possible by this lens. Specifically discussed are an electronic intraocular lens and electronic eyeglasses, both of which can be powered independently.

  11. [To guard against mistakes in selection of intraocular lenses].

    PubMed

    He, Shou-zhi

    2008-04-01

    Development of different kinds of new intraocular lenses (IOL) provide more selections to meet various clinical requirements, which may plays an active role in making cataract surgery more perfectible. But there are many misunderstandings about how to select the proper IOL. For example, "the expensive one is the best one", "new product is absolutely perfect", and so on. Some surgeons prefer more practice and ignore the summary of the experiences. Someone unilaterally exaggerates some special function of IOL When selecting the IOL, it is a common challenge for us to fully consider the patients needs, and properly manage the relationship between the basic need and special need, and to avoid fanaticism, and provide the best benefits to the patients.

  12. Diagnostic Vitrectomy for Primary Intraocular Lymphoma: When, Why, How?

    PubMed Central

    Hwang, Cindy S.; Yeh, Steven; Bergstrom, Chris S.

    2014-01-01

    Primary intraocular lymphoma (PIOL) can present with uveitis, vitritis, or chorioretinal lesions. While fluorescein angiography, fundus autofluorescence, and optical coherence tomography may aid in the diagnosis of PIOL, a definitive diagnosis can only be achieved with tissue analysis. The specimen may be obtained with a vitreous or aqueous tap, however, a diagnostic pars plana vitrectomy with acquisition of diluted and undilated vitreous fluid or a chorioretinal biopsy is preferable. Once a specimen is obtained, cytopathology, flow cytometry, immunohistochemistry, gene rearrangement studies with polymerase chain reaction, and cytokine analysis can be performed to confirm the diagnosis of PIOL. Treatment is dependent on the presentation of PIOL and may include systemic chemotherapy, local intravitreal chemotherapy, radiation or a combination of therapies. PMID:24613891

  13. Intraocular BDNF promotes ectopic branching, alters motility and stimulates abnormal collaterals in regenerating optic fibers.

    PubMed

    Dawson, Amy J; Miotke, Jill A; Meyer, Ronald L

    2015-07-10

    A great deal of effort has been invested in using trophic factors and other bioactive molecules to promote cell survival and axonal regeneration in the adult central nervous system. Far less attention has been paid to investigating potential effects that trophic factors may have that might interfere with recovery. In the visual system, BDNF has been previously reported to prevent regeneration. To test if BDNF is inherently incompatible with regeneration, BDNF was given intraocularly during optic nerve regeneration in the adult goldfish. In vivo imaging and anatomical analysis of selectively labeled axons were used as a sensitive assay for effects on regeneration within the tectum. BDNF had no detectable inhibitory effect on the ability of axons to regenerate. Normal numbers of axons regenerated into the tectum, exhibited dynamic growth and retractions similar to controls, and were able to navigate to their correct target zone in the tectum. However, BDNF was found to have additional effects that adversely affected the quality of regeneration. It promoted premature branching at ectopic locations, diminished the growth rate of axons through the tectum, and resulted in the formation of ectopic collaterals. Thus, although BDNF has robust effects on axonal behavior, it is, nevertheless, compatible with axonal regeneration, axon navigation and the formation of terminal arbors.

  14. Intracorneal and Intraocular Invasion of Ocular Surface Squamous Neoplasia after Intraocular Surgery: Report of Two Cases and Review of the Literature

    PubMed Central

    Murillo, Juan C.; Galor, Anat; Wu, Michael C.; Kye, Natasha K.; Wong, James; Ahmed, Ibrahim O.; Joag, Madhura; Shalabi, Nabeel; Lahners, William; Dubovy, Sander; Karp, Carol L.

    2017-01-01

    Purpose The aim of this paper was to describe 2 cases of ocular surface squamous neoplasia (OSSN) of the conjunctiva with intracorneal and intraocular extension following intraocular surgery. Methods We conducted a clinical pathological retrospective case series. Results Case 1 underwent cataract surgery in the setting of an unnoticed adjacent OSSN. An excisional biopsy with cryotherapy and intraoperative mitomycin C was subsequently performed, confirming OSSN. The patient had two recurrences treated topically with resolution. While the conjunctiva remained clear, a corneal haze emanating from the cataract incision site was noted. Penetrating keratoplasty (PK) for this haze revealed midstromal infiltrative carcinoma. Case 2 had a history of herpes simplex keratitis that ultimately required corneal grafts. Fifteen years later, he developed an OSSN treated with excisional biopsy and had clear margins. Eight months later, he presented with a recurrence of his OSSN and was treated briefly with topical interferon for 4 weeks; however, he developed an infectious keratitis with a corneal perforation requiring another PK. Four months after PK, low-grade inflammation was noted. Cytology of the anterior chamber aspirate revealed neoplastic squamous cells. Another PK was then performed. Pathology confirmed extensive intraocular neoplasia. Limited exenteration was performed. Conclusion Patients with a history of OSSN may be at increased risk of neoplastic intraocular extension following intraocular surgery. PMID:28275607

  15. Intravitreal infusion: A novel approach for intraocular drug delivery

    PubMed Central

    Tian, Jiao; Liu, Jia; Liu, Xiao; Xiao, Yangyan; Tang, Luosheng

    2016-01-01

    Intraocular injection has become an increasingly important intervention in the treatment of posterior segment diseases. However, an acute intraocular pressure (IOP) elevation after intravitreal injection is a common concern. This study aimed to evaluate the efficacy of intravitreal infusion in maintaining stable IOP in a rabbit model. Trypan blue (TB) 0.06% with an external pump was used to evaluate intravitreal infusion in rabbit eyes. Groups A (50 μL), B (100 μL), C (150 μL), and D (200 μL) were slowly infused over 30 minutes with TB. As a control, Group E underwent conventional intravitreal injection of 100 μL of TB. Group F received a bolus infusion of 100 μL of TB within 1 minute. The mean increases in IOP during infusion for each group were: Group A (7.93 ± 3.80 mmHg), B (13.97 ± 3.17 mmHg), C (19.91 ± 6.06 mmHg) and D (29.38 ± 8.97 mmHg). Immediately post-injection in group E the mean increase in IOP amounted to 34.33 ± 6.57 mmHg. The mean increase in IOP of group F after bolus infusion was 49.89 ± 1.71 mmHg. Intravitreal infusion maintains a stable IOP and provides a controlled infusion speed compared with intravitreal injection. PMID:27886224

  16. Intraocular Lens Fragmentation Using Femtosecond Laser: An In Vitro Study

    PubMed Central

    Bala, Chandra; Shi, Jeffrey; Meades, Kerrie

    2015-01-01

    Purpose: To transect intraocular lenses (IOLs) using a femtosecond laser in cadaveric human eyes. To determine the optimal in vitro settings, to detect and characterize gasses or particles generated during this process. Methods: A femtosecond laser was used to transect hydrophobic and hydrophilic acrylic lenses. The settings required to enable easy separation of the lens fragment were determined. The gasses and particles generated were analysed using gas chromatography mass spectrometer (GC-MS) and total organic carbon analyzer (TOC), respectively. Results: In vitro the IOL fragments easily separated at the lowest commercially available energy setting of 1 μJ, 8-μm spot, and 2-μm line separation. No particles were detected in the 0.5- to 900-μm range. No significant gasses or other organic breakdown by products were detected at this setting. At much higher energy levels 12 μJ (4 × 6 μm spot and line separation) significant pyrolytic products were detected, which could be harmful to the eye. In cadaveric explanted IOL capsule complex the laser pulses could be applied through the capsule to the IOL and successfully fragment the IOL. Conclusion: IOL transection is feasible with femtosecond lasers. Further in vivo animal studies are required to confirm safety. Translational Relevance: In clinical practice there are a number of large intraocular lenses that can be difficult to explant. This in-vitro study examines the possibility of transecting the lasers quickly using femtosecond lasers. If in-vivo studies are successful, then this innovation could help ophthalmic surgeons in IOL explantation. PMID:26101721

  17. Design of a Test Bench for Intraocular Lens Optical Characterization

    NASA Astrophysics Data System (ADS)

    Alba-Bueno, Francisco; Vega, Fidel; Millán, María S.

    2011-01-01

    The crystalline lens is the responsible for focusing at different distances (accommodation) in the human eye. This organ grows throughout life increasing in size and rigidity. Moreover, due this growth it loses transparency through life, and becomes gradually opacified causing what is known as cataracts. Cataract is the most common cause of visual loss in the world. At present, this visual loss is recoverable by surgery in which the opacified lens is destroyed (phacoemulsification) and replaced by the implantation of an intraocular lens (IOL). If the IOL implanted is mono-focal the patient loses its natural capacity of accommodation, and as a consequence they would depend on an external optic correction to focus at different distances. In order to avoid this dependency, multifocal IOLs designs have been developed. The multi-focality can be achieved by using either, a refractive surface with different radii of curvature (refractive IOLs) or incorporating a diffractive surface (diffractive IOLs). To analyze the optical quality of IOLs it is necessary to test them in an optical bench that agrees with the ISO119679-2 1999 standard (Ophthalmic implants. Intraocular lenses. Part 2. Optical Properties and Test Methods). In addition to analyze the IOLs according to the ISO standard, we have designed an optical bench that allows us to simulate the conditions of a real human eye. To do that, we will use artificial corneas with different amounts of optical aberrations and several illumination sources with different spectral distributions. Moreover, the design of the test bench includes the possibility of testing the IOLs under off-axis conditions as well as in the presence of decentration and/or tilt. Finally, the optical imaging quality of the IOLs is assessed by using common metrics like the Modulation Transfer Function (MTF), the Point Spread Function (PSF) and/or the Strehl ratio (SR), or via registration of the IOL's wavefront with a Hartmann-Shack sensor and its

  18. Intraocular lens implantation for patients with coloboma of the iris

    PubMed Central

    LI, JUANJUAN; LI, YAN; HU, ZHULIN; KONG, LEI

    2014-01-01

    The aim of this study was to analyze the techniques for intraocular lens (IOL) implantation in patients with coloboma of the iris. A retrospective cohort study was used to analyze the degree of iris coloboma and the characteristics of the crystalline lens in 56 patients with iris coloboma. The patients with a lesser degree of coloboma of the iris and an intact lens capsule were treated by iris suture and IOL implantation into the posterior chamber. Patients with an iris coloboma confined to one quadrant, severe iris atrophy and significant lens capsule coloboma were treated with an annular suture at the edge of the pupil and IOL implantation into the anterior chamber. Patients with a greater degree of iris coloboma and an intact lens capsule were treated with an artificial iris and IOL implantation. The patients were followed up for between five months and five years after surgery. Data relating to vision, photophobia, IOL location, postoperative complications and treatment were also obtained at follow-up. The vision of the patients was improved to varying degrees following the surgery, with the exception of those with amblyopia or serious corneal scars. The photophobia of the patients had also improved. The patients’ levels of satisfaction and comfort were deemed to be satisfactory. Early postoperative complications included hyphema, increased intraocular pressure and uveitis. However, serious complications such as corneal decompensation and IOL dislocation were not observed. Various techniques for IOL implantation were selected based on the degree of iris and lens capsule coloboma; these techniques were capable of improving the vision and photophobia of the patients. PMID:24926350

  19. Evidence of octacalcium phosphate and Type-B carbonated apatites deposited on the surface of explanted acrylic hydrogel intraocular lens.

    PubMed

    Lin, Shan-Yang; Chen, Ko-Hua; Li, May-Jane; Cheng, Wen-Ting; Wang, Shun-Li

    2004-08-15

    Fourier-transform infrared (FTIR) microspectroscopy combining with attenuated total reflection (ATR) microsampling technique and micro-Raman spectrophotometer were used to detect the deposited materials on the surface of acrylic hydrogel intraocular lens (IOL) with or without ocular implantation. Surface morphology and the interface of this IOL were further examined by a confocal laser scanning microscope. The brand-new IOL exhibited a very smooth, transparent and featureless surface, but the explanted IOL had an irregular cerebriform-like opaque appearance. Both FTIR/ATR and Raman microspectroscopic analyses showed the deposits on the surface of acrylic hydrogel IOL after ocular implantation to consist of octacalcium phosphate (OCP) and Type B carbonated apatites, leading to the opalescence of acrylic hydrogel IOL. Both vibrational microspectroscopic examinations also confirmed the mineralization still in progress on the surface of acrylic hydrogel IOL after ocular implantation for 2 years.

  20. Traveling Exhibitions: translating current science into effective science exhibitions

    NASA Astrophysics Data System (ADS)

    Dusenbery, P.; Morrow, C.; Harold, J.

    The Space Science Institute (SSI) of Boulder, Colorado has recently developed two museum exhibits called the Space Weather Center and MarsQuest. It is currently planning to develop two other exhibitions called Cosmic Origins and InterActive Earth. Museum exhibitions provide research scientists the opportunity to engage in a number of activities that are vital to the success of earth and space outreach programs. The Space Weather Center was developed in partnership with various research missions at NASA's Goddard Space Flight Center. The focus of the presentation will be on the Institute's MarsQuest exhibition. This project is a 5000 square-foot, 2.5M, traveling exhibition that is now touring the country. The exhibit's 3-year tour is enabling millions of Americans to share in the excitement of the scientific exploration of Mars and learn more about their own planet in the process. The associated planetarium show and education program will also be described, with particular emphasis on workshops to orient host museum staff (e.g. museum educators and docents). The workshops make innovative connections between the exhibitions interactive experiences and lesson plans aligned with the National Science Education Standards. SSI is also developing an interactive web site called MarsQuest On-line. The linkage between the web site, education program and exhibit will be discussed. MarsQuest and SSI's other exhibitions are good models for actively involving scientists and their discoveries to help improve informal science education in the museum community and for forging a stronger connection between formal and informal education.

  1. [A new permanent magnet for removal of intra-ocular ferromagnetic foreign bodies].

    PubMed

    Kuhn, F; Heimann, K

    1991-04-01

    The permanent-magnet (Sm-Co-Magnet) is described with a length of 35 mm and a diameter of 18 gauge. This magnet enables a controlled atraumatic removal of small or even larger intraocular ferromagnetic foreign bodies.

  2. [Eye diseases in dwarf rabbits. 2. Diseases of the cornea, intraocular and retrobulbar disorders, and neoplasms].

    PubMed

    Wagner, F; Heider, H J; Görig, C; Fehr, M

    1998-09-01

    In the second part of this review article the diseases affecting the cornea, intraocular and retrobulbar disorders, and eye-neoplasia of dwarf rabbits are described. These are illustrated by means of selected photographs.

  3. Posterior Segment Intraocular Foreign Body: Extraction Surgical Techniques, Timing, and Indications for Vitrectomy

    PubMed Central

    Guevara-Villarreal, Dante A.

    2016-01-01

    Ocular penetrating injury with Intraocular Foreign Body (IOFB) is a common form of ocular injury. Several techniques to remove IOFB have been reported by different authors. The aim of this publication is to review different timing and surgical techniques related to the extraction of IOFB. Material and Methods. A PubMed search on “Extraction of Intraocular Foreign Body,” “Timing for Surgery Intraocular Foreign Body,” and “Surgical Technique Intraocular Foreign Body” was made. Results. Potential advantages of immediate and delayed IOFB removal have been reported with different results. Several techniques to remove IOFB have been reported by different authors with good results. Conclusion. The most important factor at the time to perform IOFB extraction is the experience of the surgeon. PMID:28025619

  4. Capsular Block Syndrome Following Combined Cataract and Vitrectomy Surgery in a Patient With Intraocular Gas.

    PubMed

    Goodwin, Diamond M; Casey, Richard; Tsui, Irena

    2015-10-01

    The aim of this report is to describe the diagnosis, treatment, and prevention of the rare complication of capsular block syndrome following combined cataract and vitrectomy surgery in a patient with intraocular gas.

  5. Electron probe X-ray analysis of an intraocular foreign body.

    PubMed

    Chisholm, I A; Lalonde, J M; Ghadially, F N

    1977-10-01

    We describe a simple and rapid method of electron probe x-ray analysis on a foreign body removed from the eye. We demonstrated the presence of copper in an intraocular foreign body which has originated from a blank 0.22 calibre cartridge. Sodium, potassium, calcium, phosphorus, sulpher and chlorine were also detected. It seems likely that these elements were derived from the biological milieu in which the intraocular foreign body had rested for some 2 years and 9 months.

  6. Longitudinal analysis of age-related changes in intraocular pressure in South Korea

    PubMed Central

    Baek, S U; Kee, C; Suh, W

    2015-01-01

    Purpose To assess the changes in intraocular pressure (IOP) with age in South Korea Methods Subjects aged 20–79 who had been receiving health examinations at a university hospital were enrolled. They completed physical and ophthalmic examinations. Subjects with ocular disease that could possibly affect their IOP were excluded. The relationships between IOP and age, blood pressure, heart rate, body mass index, blood chemistry, and electrolyte were analyzed using a linear mixed model. Results Of the 33 712 subjects, 31 857 participants were enrolled. In a cross-sectional analysis, IOP also showed a negative correlation in all age groups (respectively, P<0.001). In particular, patients in their 60s~80s had a less steep decreasing slope of IOP with age than patients in their 20s~30s (correlation coefficient −0.260 and −0.168, respectively). In longitudinal analysis, negative trend was shown in the slope of tendency in total subjects. When analyzing the effect of gender on the relationship between age and IOP, females had a less steep decreasing slope of IOP with age than males by 0.05 mm Hg. With regard to systemic parameters, systolic blood pressure and heart rate were positively correlated with IOP (P<0.001). Conclusion IOP was significantly decreased with age, although the amount of change was small. In women and older age groups, IOP was less decreased than that of men and young age groups. In addition, IOP was positively associated with systolic blood pressure and heart rate. PMID:25697455

  7. A new device to noninvasively estimate the intraocular pressure produced during ocular compression

    PubMed Central

    Korenfeld, Michael S; Dueker, David K

    2016-01-01

    Purpose To describe a noninvasive instrument that estimates intraocular pressure during episodes of external globe compression and to demonstrate the accuracy and reliability of this device by comparing it to the intraocular pressures simultaneously and manometrically measured in cannulated eyes. Methods A thin fluid-filled bladder was constructed from flexible and inelastic plastic sheeting and was connected to a pressure transducer with high pressure tubing. The output of the pressure transducer was sent to an amplifier and recorded. This device was validated by measuring induced pressure in the fluid-filled bladder while digital pressure was applied to one surface, and the other surface was placed directly against a human cadaver eye or in vivo pig eye. The human cadaver and in vivo pig eyes were each cannulated to provide a manometric intraocular pressure control. Results The measurements obtained with the newly described device were within ~5% of simultaneously measured manometric intraocular pressures in both a human cadaver and in vivo pig eye model for a pressure range of ~15–100 mmHg. Conclusion This novel noninvasive device is useful for estimating the intraocular pressure transients induced during any form of external globe compression; this is a clinical setting where no other devices can be used to estimate intraocular pressure. PMID:26955260

  8. The significance of intraocular pressure elevation during sleep-related postures.

    PubMed

    McMonnies, Charles W

    2014-05-01

    Intraocular pressure and its fluctuations are associated with the development and progression of glaucoma. This review examines the potential for sleep-related intraocular pressure elevations to contribute to the onset and progression of glaucoma. Also considered is the potential for patient education and appropriate changes in behaviour as a means of reducing exposure to elevated intraocular pressure. A PubMed search using the combination key words 'glaucoma and sleep' was conducted. Information was taken from representative articles from the 187 yielded from the search. Additional papers were found after accessing references in selected papers. Several studies have indicated an association between the progression of glaucoma and both lateral decubitus (side sleep) and supine sleep positions. Evidence that prone sleep positions could raise intraocular pressure to high levels suggests a similar if not stronger association. Intraocular pressure elevation and progression of glaucoma associated with sleep positions suggest that there are similar risks of progression associated with sleep-related body postures adopted during non-sleep activities, such as reading, watching television and sun-bathing. Posture-related management of patients with glaucoma, which is intended to reduce the risk or degree of progression may include the use of specially designed pillows, bed-head elevation and recommendations to avoid postures which induce higher intraocular pressure.

  9. Prevalence of increased intraocular pressure in Graves' disease--evidence of frequent subclinical ophthalmopathy.

    PubMed

    Gamblin, G T; Harper, D G; Galentine, P; Buck, D R; Chernow, B; Eil, C

    1983-02-24

    Graves' exophthalmos is frequently associated with elevated intraocular pressure on upgaze. Eighty patients with Graves' disease were evaluated prospectively by applanation tonometry to assess the prevalence of ophthalmopathy in this disorder. Whereas 21 (26 per cent) of the 80 patients had exophthalmos, 61 (76 per cent) had abnormal intraocular pressure (delta greater than or equal to 3 mm Hg). All patients with exophthalmos had elevated intraocular pressure on upgaze; 40 (68 per cent) of 59 patients without proptosis had abnormal pressure readings. The mean interval between the onset of Graves' disease and this study was 6.3 +/- 1.0 years (S.E.M.) for those patients who had exaggerated positional changes in intraocular pressure, as compared with 3.0 +/- 1.0 years for those with normal intraocular pressure (P less than 0.005). All but 1 of 15 patients in whom the diagnosis of Graves' disease had been documented 10 or more years earlier had increased intraocular pressure on upgaze. We conclude that Graves' ophthalmopathy is more common than is recognized clinically and that eye involvement is an inevitable complication of the disease.

  10. Development of a multiple-drug delivery implant for intraocular management of proliferative vitreoretinopathy.

    PubMed

    Zhou, T; Lewis, H; Foster, R E; Schwendeman, S P

    1998-11-13

    A prototype multiple-drug delivery implant has been developed for the intraocular management of proliferative vitreoretinopathy (PVR). Because of the recurrent nature of the disease, PVR causes blindness in approximately 7% of patients who have undergone retinal re-attachment surgery. The poly(dl-lactide-co-glycolide) 50/50 (PLGA) implant consists of three cylindrical segments, each of which contains one of the following drugs: 5-fluorouridine (5FUrd, an antimetabolite), triamcinolone (Triam, a corticosteroid), and human recombinant tissue plasminogen activator (t-PA, a thrombolytic agent). The device can be inserted through a 20-gauge syringe needle into the vitreous body of the eye. The implant also possesses a PLGA coating over the t-PA-containing terminal segment, which creates a lag-time to deliver t-PA when most needed and to decrease the risk of postoperative bleeding. Two methods of cylinder fabrication were investigated: heat and solvent extrusion. The release behavior of several drugs was examined as a function of the processing variables including: extrusion method, drug loading, polymer molecular weight, and drug particle size. The presence of either the organic solvent (acetone) during processing or a highly water-soluble drug (5FUrd) in the formulation increased the polymer porosity, which in turn, increased the drug release-rate. Drug loading effects were consistent with percolation concepts, and a low-molecular-weight PLGA (e.g., Mw=42000 for inherent viscosity=0.58 dl/g) was desirable to produce controlled release close to one month. Based on pharmacological and pharmacokinetic data of these compounds and our clinical experience with this disease, several design criteria for a combined implant were devised. Optimal cylindrical segments from the formulation studies were selected and combined in series to form a contiguous implant. After successful combination and coating procedures were developed, prototype implants were prepared. From the 3-drug

  11. Lowered intraocular pressure in a glaucoma patient after intravitreal injection of ocriplasmin

    PubMed Central

    McClintock, Michael; MacCumber, Mathew W

    2015-01-01

    We report the case of a glaucoma patient who received a single intravitreal injection of 125 µg ocriplasmin for vitreomacular traction in the right eye. The patient had bilateral advanced glaucoma and had previously undergone an implantation of an Ahmed glaucoma valve in the right eye and trabeculectomy in both eyes. The patient was using three topical ophthalmic intraocular pressure (IOP)-lowering medications on the day of injection. Baseline uncorrected Snellen visual acuity was 20/80-1 and IOP was 19 mmHg. Resolution of vitreomacular traction was achieved 1 week after injection. IOP was transiently decreased, reaching a maximum reduction of 12 mmHg below baseline at 1 month after injection, when serous choroidal effusion was also present. IOP returned to baseline levels and choroidal effusion resolved at 2 months after injection of IOP-lowering medication. Vitrectomy with epiretinal membrane and internal limiting membrane peeling, endolaser photocoagulation, and fluid–gas exchange were performed in the right eye ~3.5 months after injection to treat persistent epiretinal membrane, and presumed tractional retinal detachment. Final visual acuity was 20/50+ and IOP was 18 mmHg at 16 weeks after surgery. To our knowledge, this is the first report of IOP reduction and serous choroidal effusion after ocriplasmin injection. PMID:26604668

  12. Intraocular pressure (IOP) in relation to four levels of daily geomagnetic and extreme yearly solar activity

    NASA Astrophysics Data System (ADS)

    Stoupel, E.; Goldenfeld, M.; Shimshoni, M.; Siegel, R.

    1993-03-01

    The link between geomagnetic field activity (GMA), solar activity and intraocular pressure (IOP) in healthy individuals was investigated. The IOP of 485 patients (970 eyes) was recorded over three nonconsecutive years (1979, 1986, 1989) which were characterized by maximal solar activity (1979, 1989) or minimal solar activity (1986). The measurements were also correlated with four categories of GMA activity: quiet (level I0), unsettled (II0), active (III0), and stormy (IV0). Participants were also differentiated by age and sex. We found that IOP was lowest on days of level IV0 (stormy) GMA. The drop in IOP concomitant with a decrease in GMA level was more significant during periods of low solar activity and in persons over 65 years of age. There was a trend towards higher IOP values on days of levels II0 and IV0 GMA in years of high solar activity. Differences between the sexes and among individuals younger than 65 years were not significant. Our results show an interesting aspect of environmental influence on the healthy population.

  13. Quantitative analysis of posterior capsule opacification of hydrophobic acrylic intraocular lenses.

    PubMed

    Oharazawa, Hideaki; Suzuki, Hisaharu; Shibata, Keiko; Yamada, Yumi; Matsui, Hironori; Shiwa, Toshihiko; Takahashi, Hiroshi; Ohara, Kunitoshi

    2007-02-01

    Posterior capsule opacification (PCO) remains a common complication of modern cataract surgery, although both modification of materials used and changes in the intraocular lens (IOL) optic edge design have helped to decrease its incidence slightly. Recently, various kinds of quantitative methods have been developed for measuring PCO. The purpose of this study was to compare the quantitative analysis of PCO between different types of IOL designs. Patients enrolled in the study had age-related cataract and underwent uneventful cataract surgery and implantation of either the AcrySof MA30BA (Alcon) or the Sensor AR40e (AMO), which are differently designed hydrophobic acrylic IOLs with a sharp-edged optic design. Postoperative examination was performed at 6 months. Retroillumination photographs of each eye were obtained, and the degree of PCO was assessed using the Evaluation of Posterior Capsule Opacification (EPCO) system. Grade 1 PCO was noted in both the MA30BA and the AR40e groups. There was no significant difference in the mean PCO score between the MA30BA and AR40e groups. Although the sharp-edged optic designs of both IOLs might similarly inhibit PCO at 6 months, a long-term follow-up period is needed to determine if any PCO differences occur between these 2 hydrophobic acrylic IOLs.

  14. On seeing yellow: the case for, and against, short-wavelength light-absorbing intraocular lenses.

    PubMed

    Simunovic, Matthew P

    2012-07-01

    The normal human crystalline lens absorbs UV and short-wavelength visible electromagnetic radiation. Early intraocular lenses (IOLs) permitted the transmission of such radiation to the retina following cataract extraction. Experimental studies of the absorption profile of the crystalline lens and animal studies demonstrating the deleterious effects of short-wavelength radiation on the retina led to the development of UV-absorbing, and later, short-wavelength light-absorbing (SLA) IOLs. Short-wavelength light-absorbing IOLs were designed to mimic the absorption properties of the normal crystalline lens by absorbing some short-wavelength light in addition to UV radiation; however, debate continues regarding the relative merits of such lenses over UV-absorbing IOLs. Advocates of SLA IOLs suggest that they may theoretically offer increased photoprotection and decreased glare sensitivity and draw on in vitro, animal, and limited clinical studies that infer possible benefits. Detractors suggest that there is no direct evidence supporting a role for SLA IOLs in preventing retinal dysfunction in humans and suggest that they may have negative effects on color perception, scotopic vision, and circadian rhythms. This article examines the theoretical and empirical evidence for, and against, such lenses.

  15. Comparison of dose calculation methods for brachytherapy of intraocular tumors

    SciTech Connect

    Rivard, Mark J.; Chiu-Tsao, Sou-Tung; Finger, Paul T.; Meigooni, Ali S.; Melhus, Christopher S.; Mourtada, Firas; Napolitano, Mary E.; Rogers, D. W. O.; Thomson, Rowan M.; Nath, Ravinder

    2011-01-15

    Purpose: To investigate dosimetric differences among several clinical treatment planning systems (TPS) and Monte Carlo (MC) codes for brachytherapy of intraocular tumors using {sup 125}I or {sup 103}Pd plaques, and to evaluate the impact on the prescription dose of the adoption of MC codes and certain versions of a TPS (Plaque Simulator with optional modules). Methods: Three clinical brachytherapy TPS capable of intraocular brachytherapy treatment planning and two MC codes were compared. The TPS investigated were Pinnacle v8.0dp1, BrachyVision v8.1, and Plaque Simulator v5.3.9, all of which use the AAPM TG-43 formalism in water. The Plaque Simulator software can also handle some correction factors from MC simulations. The MC codes used are MCNP5 v1.40 and BrachyDose/EGSnrc. Using these TPS and MC codes, three types of calculations were performed: homogeneous medium with point sources (for the TPS only, using the 1D TG-43 dose calculation formalism); homogeneous medium with line sources (TPS with 2D TG-43 dose calculation formalism and MC codes); and plaque heterogeneity-corrected line sources (Plaque Simulator with modified 2D TG-43 dose calculation formalism and MC codes). Comparisons were made of doses calculated at points-of-interest on the plaque central-axis and at off-axis points of clinical interest within a standardized model of the right eye. Results: For the homogeneous water medium case, agreement was within {approx}2% for the point- and line-source models when comparing between TPS and between TPS and MC codes, respectively. For the heterogeneous medium case, dose differences (as calculated using the MC codes and Plaque Simulator) differ by up to 37% on the central-axis in comparison to the homogeneous water calculations. A prescription dose of 85 Gy at 5 mm depth based on calculations in a homogeneous medium delivers 76 Gy and 67 Gy for specific {sup 125}I and {sup 103}Pd sources, respectively, when accounting for COMS-plaque heterogeneities. For off

  16. Functionalised polysiloxanes as injectable, in situ curable accommodating intraocular lenses.

    PubMed

    Hao, Xiaojuan; Jeffery, Justine L; Wilkie, John S; Meijs, Gordon F; Clayton, Anthony B; Watling, Jason D; Ho, Arthur; Fernandez, Viviana; Acosta, Carolina; Yamamoto, Hideo; Aly, Mohamed G M; Parel, Jean-Marie; Hughes, Timothy C

    2010-11-01

    The aged eye's ability to change focus (accommodation) may be restored by replacing the hardened natural lens with a soft gel. Functionalised polysiloxane macromonomers, designed for application as an injectable, in situ curable accommodating intraocular lens (A-IOL), were prepared via a two-step synthesis. Prepolymers were synthesised via ring opening polymerisation (ROP) of octamethylcyclotetrasiloxane (D(4)) and 2,4,6,8-tetramethylcyclotetrasiloxane (D(4)(H)) in toluene using trifluoromethanesulfonic acid (TfOH) as catalyst. Hexaethyldisiloxane (HEDS) was used as the end group to control the molecular weight of the prepolymers, which were then converted to macromonomers by hydrosilylation of the SiH groups with allyl methacrylate (AM) to introduce polymerisable groups. The resulting macromonomers had an injectable consistency and thus, were able to be injected into and refill the empty lens capsular bag. The macromonomers also contained a low ratio of polymerisable groups so that they may be cured on demand, in situ, under irradiation of blue light, in the presence of a photo-initiator, to form a soft polysiloxane gel (an intraocular lens) in the eye. The pre-cure viscosity and post-cure modulus of the polysiloxanes, which are crucial factors for an injectable, in situ curable A-IOL application, were controlled by adjusting the end group and D(4)(H) concentrations, respectively, in the ROP. The macromonomers were fully cured within 5 min under light irradiation, as shown by the rapid change in modulus monitored by photo-rheology. Ex vivo primate lens stretching experiments on an Ex Vivo Accommodation Simulator (EVAS) showed that the polysiloxane gel refilled lenses achieved over 60% of the accommodation amplitude of the natural lens. An in vivo biocompatibility study in rabbits using the lens refilling (Phaco-Ersatz) procedure demonstrated that the soft gels had good biocompatibility with the ocular tissue. The polysiloxane macromonomers meet the targeted

  17. Role of TLR5 and flagella in bacillus intraocular infection.

    PubMed

    Parkunan, Salai Madhumathi; Astley, Roger; Callegan, Michelle C

    2014-01-01

    B. cereus possesses flagella which allow the organism to migrate within the eye during a blinding form of intraocular infection called endophthalmitis. Because flagella is a ligand for Toll-like receptor 5 (TLR5), we hypothesized that TLR5 contributed to endophthalmitis pathogenesis. Endophthalmitis was induced in C57BL/6J and TLR5-/- mice by injecting 100 CFU of B. cereus into the mid-vitreous. Eyes were analyzed for intraocular bacterial growth, retinal function, and inflammation by published methods. Purified B. cereus flagellin was also injected into the mid-vitreous of wild type C57BL/6J mice and inflammation was analyzed. TLR5 activation by B. cereus flagellin was also analyzed in vitro. B. cereus grew rapidly and at similar rates in infected eyes of C57BL/6J and TLR5-/- mice. A significant loss in retinal function in both groups of mice was observed at 8 and 12 hours postinfection. Retinal architecture disruption and acute inflammation (neutrophil infiltration and proinflammatory cytokine concentrations) increased and were significant at 8 and 12 hours postinfection. Acute inflammation was comparable in TLR5-/- and C57BL/6J mice. Physiological concentrations of purified B. cereus flagellin caused significant inflammation in C57BL/6J mouse eyes, but not to the extent of that observed during active infection. Purified B. cereus flagellin was a weak agonist for TLR5 in vitro. These results demonstrated that the absence of TLR5 did not have a significant effect on the evolution of B. cereus endophthalmitis. This disparity may be due to sequence differences in important TLR5 binding domains in B. cereus flagellin or the lack of flagellin monomers in the eye to activate TLR5 during infection. Taken together, these results suggest a limited role for flagellin/TLR5 interactions in B. cereus endophthalmitis. Based on this and previous data, the importance of flagella in this disease lies in its contribution to the motility of the organism within the eye during

  18. Mechanisms for vasopressin effects on intraocular pressure in anesthetized rats

    NASA Technical Reports Server (NTRS)

    Balaban, C. D.; Palm, D. E.; Shikher, V.; Searles, R. V.; Keil, L. C.; Severs, W. B.

    1997-01-01

    Continuous intracameral infusions of a balanced salt solution (0.175 microliter min-1) have been reported to raise intraocular pressure (IOP) in anesthetized rats. Palm et al. (1995) previously reported that this effect was attenuated significantly by inclusion of arginine-vasopressin (AVP, 10 ng 0.175 microliter-1) in the infusate. This study used experimental and computer simulation methods to investigate factors underlying these changes in IOP. First, constant intracameral infusions of artificial cerebrospinal fluid (aCSF) at different fixed rates (0.049-0.35 microliter min-1) were used to estimate the outflow resistance. Secondly, IOP responses were measured during an 2 hr intracameral infusion of either aCSF or AVP that was the sum of a small constant component (0.05 microliter min-1) and a larger periodic component (0.25 microliter min-1, cycling for 4 min on, then 4 min off); the mean infusion rate was 0.175 microliter min-1. As shown previously for 0.175 microliter min-1 constant infusions, the periodic aCSF infusion induced a significant rise in IOP that was attenuated by AVP administration. Complex demodulation analysis and the estimated gain parameter of a second order transfer function fit to the periodic responses indicated that outflow resistance increased significantly during the infusions in both aCSF and AVP groups, but that the indices of resistance did not differ significantly between aCSF and AVP infused eyes. This finding implies that changes in outflow resistance do not explain the difference in IOP responses to intracameral aCSF and AVP. The two responses differed significantly, though, in damping factors, such that the aCSF responses were considerably more underdamped than the AVP responses. It is hypothesized that aCSF-induced increase in IOP reflects both (1) a small component reflecting increased outflow resistance and (2) a larger non-resistive component. Since the non-resistive component is insensitive to pretreatment with acetazolamide

  19. Dislocation of polyfocal full-optics accommodative intraocular lens after neodymium-doped yttrium aluminum garnet capsulotomy in vitrectomized eye.

    PubMed

    Kang, Kyung Tae; Kim, Yu Cheol

    2013-11-01

    We report a case of dislocation of WIOL-CF® polyfocal full-optics intraocular lens (IOL) after neodymium-doped yttrium aluminum garnet (Nd: YAG) laser capsulotomy in the vitrectomized eye. At 22 months before the dislocation of the IOL, a 55-year-old male patient underwent phacoemulsification with WIOL-CF® IOL implantation in a local clinic and 10 months after the cataract surgery the patient underwent pars plana vitrectomy, endolaser photocoagulation and 14% C 3 F 8 gas tamponade for the treatment of rhegmatogenous retinal detachment. At 9 months after the vitrectomy, the patient visited our clinic for a sudden decrease of vision after Nd: YAG capsulotomy in the local clinic. On fundus examination, the dislocated IOL was identified and the Nd: YAG capsulotomy site and the larger break, which is suspected to have been a route of the dislocation were observed in the posterior capsule.

  20. A novel full-angle scanning light scattering profiler to quantitatively evaluate forward and backward light scattering from intraocular lenses

    SciTech Connect

    Walker, Bennett N.; James, Robert H.; Ilev, Ilko K.; Calogero, Don

    2015-09-15

    Glare, glistenings, optical defects, dysphotopsia, and poor image quality are a few of the known deficiencies of intraocular lenses (IOLs). All of these optical phenomena are related to light scatter. However, the specific direction that light scatters makes a critical difference between debilitating glare and a slightly noticeable decrease in image quality. Consequently, quantifying the magnitude and direction of scattered light is essential to appropriately evaluate the safety and efficacy of IOLs. In this study, we introduce a full-angle scanning light scattering profiler (SLSP) as a novel approach capable of quantitatively evaluating the light scattering from IOLs with a nearly 360° view. The SLSP method can simulate in situ conditions by controlling the parameters of the light source including angle of incidence. This testing strategy will provide a more effective nonclinical approach for the evaluation of IOL light scatter.

  1. Calcification of a hydrophilic acrylic intraocular lens after Descemet-stripping endothelial keratoplasty: case report and laboratory analyses.

    PubMed

    Fellman, Melissa A; Werner, Liliana; Liu, Erica T; Stallings, Shannon; Floyd, Anne M; van der Meulen, Ivanka J E; Lapid-Gortzak, Ruth; Nieuwendaal, Carla P

    2013-05-01

    We describe the case of an 83-year-old woman who had uneventful phacoemulsification with implantation of a tripod hydrophilic acrylic intraocular lens (IOL). Because of postoperative corneal decompensation, 2 Descemet-stripping endothelial keratoplasty (DSEK) procedures were performed within 2 years. After the second procedure, the graft was not well attached, requiring an intracameral injection of air on day 3. Approximately 9 months later, opacification was observed on the anterior surface of the IOL, with a significant decrease in visual acuity. The IOL was explanted within the capsular bag. Laboratory analyses revealed granular deposits densely distributed in a round pattern within the margins of the capsulorhexis. Granules were located at the anterior surface/subsurface of the IOL and stained positive for calcium (alizarin red and von Kossa method). Scheimpflug photography revealed high levels of light scattering from the opacified area. Surgeons should be aware of possible localized calcification following DSEK procedures in pseudophakic patients with hydrophilic acrylic IOLs.

  2. Safety and efficacy of phacoemulsification and intraocular lens implantation through a small pupil using minimal iris manipulation

    PubMed Central

    Papaconstantinou, Dimitris; Kalantzis, George; Brouzas, Dimitris; Kontaxakis, Anastasios; Koutsandrea, Chryssanthi; Diagourtas, Andreas; Georgalas, Ilias

    2016-01-01

    Purpose The aim of this study was to compare the results of phacoemulsification through a small pupil using minimal iris manipulation versus phacoemulsification through a well-dilated pupil. Methods This prospective randomized control (comparative) study comprised 78 patients (group I) with a maximally dilated pupil size of ≤4.00 mm and 45 patients (group II) with dilated pupil size of ≥7.00 mm. In group I patients, only viscodilation and minimal push-and-pull iris stretching with two collar-button iris-retractor hooks were utilized without iris manipulation. Phacoemulsification was performed by two senior surgeons and the technique used consisted of either stop and chop or quick chop, infusion/aspiration of lens cortex, capsular bag refill with ocular viscoelastic devices, and implantation of an acrylic foldable intraocular lens. Patients were examined on the first day and 1 month postoperatively. Results Forty-six eyes of group I patients had pseudoexfoliation syndrome, eleven eyes had previous glaucoma surgery, 14 eyes had angle-closure or open-angle glaucoma, and seven eyes had posterior synechiae with iritis. In group I patients, the mean pupil size measured under an operating microscope was 3.2 mm preoperatively, 4.3 mm after viscoelastic and mechanical pupil dilation, and 4.1 mm at the end of a surgical procedure. Rupture of the zonular fibers occurred in six patients of group I and the intraocular lens was implanted in the sulcus. Small iris-sphincter rupture and small hemorrhages occurred in four eyes during pupillary manipulation, but they were not evident at the end of the surgery. In group II patients, no intraoperative complications occurred. Signs of significant corneal edema and iritis were observed more frequently in group I eyes (26 eyes and 20 eyes, respectively) on the first postoperative day in comparison with group II eyes (ten eyes and six eyes, respectively). Intraocular pressure was <20 mmHg in all eyes of both groups. One month

  3. Intraocular pressure is sensitive to cumulative and instantaneous mental workload.

    PubMed

    Vera, Jesús; Jiménez, Raimundo; García, José Antonio; Cárdenas, David

    2017-04-01

    We used a repeated-measures design to assess the impact of mental-task complexity on intraocular pressure (IOP). Fourteen participants performed three continuous 11-min blocks of a mental-workload task (3-back) and an oddball version of this task. Also, heart-rate variability (HRV), cognitive-performance scores, and subjective measure of mental load (NASA-TLX) were determined. IOP was taken before each block and afterwards as well as after recovery from mental tasks. We found that IOP increased during heavy mental workloads (p < 0.01). Consistent with this finding, the autonomic control (HRV) and the cognitive performance were significantly lower (p < 0.045, and p < 0.01, respectively), and the NASA-TLX scores were higher during the 3-back task (p < 0.01). We conclude that IOP is sensitive to mental workload, and it could provide a novel neuroergonomic tool to assess mental workload. Our study highlights a potential association between IOP and the nervous system's state of activation.

  4. Effect of four different intraocular lenses on posterior capsule opacification

    PubMed Central

    Duman, Rahmi; Karel, Fatih; Özyol, Pelin; Ateş, Can

    2015-01-01

    AIM To evaluate the impact of 4 different intraocular lenses (IOLs) on posterior capsule opacification (PCO) by comparing the neodymium: yttrium-aluminum-garnet (Nd:YAG) laser capsulotomy rates. METHODS This retrospective study included 4970 eyes of 4013 cataract patients who underwent phacoemulsification and IOL implantation between January 2000 and January 2008 by the same surgeon at one clinic. Four different IOLs were assessed. The outcome parameter was the incidence of Nd:YAG laser posterior capsulotomies. RESULTS An Nd:YAG laser posterior capsulotomy was performed in 153 (3.07%) of the 4970 eyes. The mean follow-up time was 84mo for all of the IOL groups. The percentage of eyes developing PCO was significantly greater for the acrylic hydrophilic IOLs than for the hydrophobic IOLs, although eyes with acrylic hydrophilic IOLs did not require Nd:YAG laser capsulotomy as soon as eyes with acrylic hydrophobic IOLs. There was no difference between the long-term PCO rates when 1- and 3-piece acrylic hydrophobic IOLs were compared or when IOLs made of the same material but with different haptic angles were compared. CONCLUSION In this study, eyes with acrylic hydrophilic IOLs were more likely to develop PCO than those with acrylic hydrophobic IOLs. The lens design (1-piece versus 3-piece and varying haptic angles) did not affect the PCO rate. PMID:25709920

  5. Prognostic Factor Analysis of Intraocular Pressure with Neovascular Glaucoma.

    PubMed

    Nakano, Satoko; Nakamuro, Takako; Yokoyama, Katsuhiko; Kiyosaki, Kunihiro; Kubota, Toshiaki

    2016-01-01

    Purpose. To perform multivariate analysis for identifying independent predictors of elevated intraocular pressure (IOP) with neovascular glaucoma (NVG), including antivascular endothelial growth factor (VEGF) intravitreal injections. Methods. We retrospectively reviewed 142 NVG patients (181 eyes) with ischemic retinal diseases [proliferative diabetic retinopathy (PDR) in 134 eyes, retinal vein occlusion (RVO) in 29, and ocular ischemic syndrome in 18]. We analyzed age, gender, initial/final LogMAR VA, initial/final IOP, extent of iris and/or angle neovascularization, treatments, preexisting complications, concurrent medications, and follow-up duration. Results. The mean follow-up duration was 23.8 ± 18.8 months. At the final follow-up, 125 (72.3%) eyes had IOP ≤ 21 mmHg. NVG patients with RVO had a higher degree of angle closure and higher IOP. NVG with PDR had better IOP and LogMAR VA. Angle closure had the greatest impact on final IOP. Greater than 90% of patients treated with trabeculectomy with mitomycin C (LEC) had persistent declines in IOP (≤21 mmHg). Stand-alone and combination anti-VEGF therapies were not associated with improved long-term prognosis of IOP. Conclusions. Angle closure was found to have the greatest effect on NVG-IOP prognosis. When target IOP values are not obtained after adequate PRP with or without anti-VEGF, early LEC may improve the prognosis of IOP.

  6. Intraocular Pressure Induced Retinal Changes Identified Using Synchrotron Infrared Microscopy

    PubMed Central

    Chow, Seong Hoong; Wang, Jiang-Hui; He, Zheng; Nguyen, Christine; Lin, Tsung-Wu; Bui, Bang V.

    2016-01-01

    Infrared (IR) spectroscopy has been used to quantify chemical and structural characteristics of a wide range of materials including biological tissues. In this study, we examined spatial changes in the chemical characteristics of rat retina in response to intraocular pressure (IOP) elevation using synchrotron infrared microscopy (SIRM), a non-destructive imaging approach. IOP elevation was induced by placing a suture around the eye of anaesthetised rats. Retinal sections were collected onto transparent CaF2 slides 10 days following IOP elevation. Using combined SIRM spectra and chemical mapping approaches it was possible to quantify IOP induced changes in protein conformation and chemical distribution in various layers of the rat retina. We showed that 10 days following IOP elevation there was an increase in lipid and protein levels in the inner nuclear layer (INL) and ganglion cell layer (GCL). IOP elevation also resulted in an increase in nucleic acids in the INL. Analysis of SIRM spectra revealed a shift in amide peaks to lower vibrational frequencies with a more prominent second shoulder, which is consistent with the presence of cell death in specific layers of the retina. These changes were more substantial in the INL and GCL layers compared with those occurring in the outer nuclear layer. These outcomes demonstrate the utility of SIRM to quantify the effect of IOP elevation on specific layers of the retina. Thus SIRM may be a useful tool for the study of localised tissue changes in glaucoma and other eye diseases. PMID:27711151

  7. Prognostic Factor Analysis of Intraocular Pressure with Neovascular Glaucoma

    PubMed Central

    Nakamuro, Takako; Yokoyama, Katsuhiko; Kiyosaki, Kunihiro

    2016-01-01

    Purpose. To perform multivariate analysis for identifying independent predictors of elevated intraocular pressure (IOP) with neovascular glaucoma (NVG), including antivascular endothelial growth factor (VEGF) intravitreal injections. Methods. We retrospectively reviewed 142 NVG patients (181 eyes) with ischemic retinal diseases [proliferative diabetic retinopathy (PDR) in 134 eyes, retinal vein occlusion (RVO) in 29, and ocular ischemic syndrome in 18]. We analyzed age, gender, initial/final LogMAR VA, initial/final IOP, extent of iris and/or angle neovascularization, treatments, preexisting complications, concurrent medications, and follow-up duration. Results. The mean follow-up duration was 23.8 ± 18.8 months. At the final follow-up, 125 (72.3%) eyes had IOP ≤ 21 mmHg. NVG patients with RVO had a higher degree of angle closure and higher IOP. NVG with PDR had better IOP and LogMAR VA. Angle closure had the greatest impact on final IOP. Greater than 90% of patients treated with trabeculectomy with mitomycin C (LEC) had persistent declines in IOP (≤21 mmHg). Stand-alone and combination anti-VEGF therapies were not associated with improved long-term prognosis of IOP. Conclusions. Angle closure was found to have the greatest effect on NVG-IOP prognosis. When target IOP values are not obtained after adequate PRP with or without anti-VEGF, early LEC may improve the prognosis of IOP. PMID:27579175

  8. Experimental characterization of the imaging properties of multifocal intraocular lenses

    NASA Astrophysics Data System (ADS)

    Gobbi, Pier Giorgio; Fasce, Francesco; Bozza, Stefano; Brancato, Rosario

    2003-07-01

    Many different types of intraocular lenses (IOL) are currently available for implantation, both as crystalline lens replacements and as phakic refractive elements. Their optical design is increasingly sophisticated, including aspherical surface profiles and multi-zone multifocal structures, however a quantitative and comparative characterization of their imaging properties is lacking. Also a qualitative visualization of their properties would be very useful for patients in the lens choice process. To this end an experimental eye model has been developed to allow for simulated in-vivo testing of IOLs. The model cornea is made of PMMA with a dioptric power of 43 D, and it has an aspherical profile designed to minimize spherical aberration across the visible spectrum. The eye model has a variable iris and a mechanical support to accomodate IOLs, immersed in physiological solution. The eye length is variable and the retina is replaced by a glass plate. The image formed on this "retina" is optically conjugated to a CCD camera, with a suitable magnification in order to mimic the human fovea resolution, and displayed onto a monitor. With such an opto-mechanical eye model, two types of images have been used to characterize IOLs: letter charts and variable contrast gratings, in order to directly simulate human visual acuity and contrast sensitivity.

  9. Design and fabrication of a microstructured bifocal intraocular lens

    NASA Astrophysics Data System (ADS)

    Stork, Wilhelm; Wagner, Armin; Kreiner, Christine F.; Mueller-Glaser, Klaus-Dieter

    1999-06-01

    Intraocular lenses IOLs allow the vision restoration of cataract patients. However the ability of accommodation is lost after cataract surgery. Multifocal lenses show two or more foci with different refractive powers. Far and near objects can be at focus simultaneously. No additional spectacles are necessary. Bifocal lenses can be fabricated as multizone or as diffractive lenses. Diffractive multifocal lenses show in contrast to multi zone multifocal lenses no change of the brightness ratio for the far and near focus with change of the pupil diameter. Diffractive lenses show a saw tooth like microscopic shape with a geometrical height of the teeth in the order of microns. The lens was fabricated with a mold technique in a flexible silicone material. The molds have been lathed in metal with a ultra precision diamond lathe machine. For the test of the optical performance a MTF-measurement machine was constructed for multifocal lenses. With this machine the imaging quality and the intensity ratio of the two foci were measured. The optical quality of the lens turned out to be diffraction limited. At the University Hospital of Giessen, Germany a first clinical evaluation with 23 patients has been performed and proved for the high quality of the manufactured IOLs.

  10. Customized computer models of eyes with intraocular lenses

    NASA Astrophysics Data System (ADS)

    Rosales, P.; Marcos, S.

    2007-03-01

    We compared experimental wave aberrations in pseudophakic eyes with aspheric intraocular lenses (IOLs) to simulate aberrations from numerical ray tracing on customized computer eye models using corneal topography, angle λ, ocular biometry, IOL geometry, and IOL tilt and decentration measured on the same eyes. We found high correlations between real and simulated aberrations even for the eye with only the cornea, and these increased on average when the IOL geometry and position were included. Relevant individual aberrations were well predicted by the complete eye model. Corneal spherical aberration and horizontal coma were compensated by the IOL, and in 58.3% of the cases IOL tilt and decentration contributed to compensation of horizontal coma. We conclude that customized computer eye models are a good representation of real eyes with IOLs and allow understanding of the relative contribution of optical, geometrical and surgically-related factors to image quality. Corneal spherical aberration is reduced by aspheric IOLs, although other corneal high order aberrations are still a major contributor to total aberrations in pseudophakic eyes. Tilt and decentration of the IOLs represent a relatively minor contribution of the overall optical quality of the eye.

  11. Photoacoustic imaging features of intraocular tumors: Retinoblastoma and uveal melanoma

    PubMed Central

    Xu, Guan; Xue, Yafang; Özkurt, Zeynep Gürsel; Slimani, Naziha; Hu, Zizhong; Wang, Xueding; Xia, Kewen; Ma, Teng; Zhou, Qifa; Demirci, Hakan

    2017-01-01

    The purpose of this study is to examine the capability of photoacoustic (PA) imaging (PAI) in assessing the unique molecular and architectural features in ocular tumors. A real-time PA and ultrasonography (US) parallel imaging system based on a research US platform was developed to examine retinoblastoma in mice in vivo and human retinoblastoma and uveal melanoma ex vivo. PA signals were generated by optical illumination at 720, 750, 800, 850, 900 and 950 nm delivered through a fiber optical bundle. The optical absorption spectra of the tumors were derived from the PA images. The optical absorption spectrum of each tumor was quantified by fitting to a polynomial model. The microscopic architectures of the tumors were quantified by frequency domain analysis of the PA signals. Both the optical spectral and architectural features agree with the histological findings of the tumors. The mouse and human retinoblastoma showed comparable total optical absorption spectra at a correlation of 0.95 (p<0.005). The quantitative PAI features of human retinoblastoma and uveal melanoma have shown statistically significant difference in two tailed t-tests (p<0.05). Fully compatible with the concurrent procedures, PAI could be a potential tool complementary to other diagnostic modalities for characterizing intraocular tumors. PMID:28231293

  12. Influence of intraocular lens subsurface nanoglistenings on functional visual acuity

    PubMed Central

    Miyata, Kazunori; Hayashidera, Takeshi; Iida, Masaharu; Takada, Keita; Minami, Keiichiro; Oshika, Tetsuro

    2017-01-01

    To investigate the influence of intraocular lens subsurface nanoglistenings (SSNGs) on functional visual acuity (FVA), thirty-nine eyes of 29 patients were examined in this study. The SSNG group comprised 19 eyes of 14 patients (75.7± 5.4 years, mean ± standard deviation), and the control group comprised 20 eyes of 15 patients (73.6 ± 6.5 years). The SSNGs were diagnosed on the basis of the typical whitish IOL appearance upon slit-lamp examination and results of densitometry regarding surface light scattering using Scheimpflug images. The FVA measurement system (AS-28; Kowa, Aichi, Japan) was used to examine changes in continuous visual acuity (VA) over time, and visual function parameters such as FVA, visual maintenance ratio (VMR), maximum VA, minimum VA, standard deviation of VA, and number of blinks were assessed. The results were compared between the SSNG and control groups, and correlations of FVA parameters with the intensity of surface light scattering, time after surgery, and age were also evaluated. There were significant differences in VMR (P = 0.035) and standard deviation of VAs (P = 0.031) between the two groups, although no significant differences were found in baseline VA, FVA, maximum VA, minimum VA, and number of blinks. None of the FVA parameters showed any significant correlations with the intensity of surface light scattering, time after surgery, or age. There is a possibility that VA is unstable during a continuous gazing task in patients with SSNGs. PMID:28328997

  13. Noncontact measurement of intraocular pressure using a modified Michelson interferometer

    NASA Astrophysics Data System (ADS)

    Drescher, Joerg; Stork, Wilhelm; Hey, Stefan; Gundlach, Arnd; Mueller-Glaser, Klaus-Dieter; Kreiner, Christine F.

    1999-06-01

    This paper describes a new method to examine the intraocular pressure (IOP) without any contact with the eye. In our new approach the IOP is determined indirectly from the acoustic properties of the eye, as the resonance frequencies of the bulbus are shifting with increasing IOP. In a first step simulations were made with the Finite Element Method to explore the correlation between the IOP and the acoustic properties of the bulbus. The results showed a significant rise of the resonance-frequencies with increasing IOP. Simultaneously a in-vitro measurement system was built comprising a modified michelson interferometer to measure the vibrations, a transducer to stimulate the eye and a controlling PC. With this system measurements were made with artificial eyes and enucleated pig eyes to prove the correlation experimentally. The eyes were stimulated both contacting the eye with a transducer by a stick and contactless with sonic waves. Several series of measurements showed a proportional constant of 1,25 Hz/mmHg in average, which can be detected easily. The standard deviation measuring different pig eyes was 4,5 mmHg. Next a in-vivo system was developed to study the acoustic behavior of the human eye in the real environment. The in-vivo system consists of a miniaturized semiconductor-laser interferometer complying laser safety requirements, an automatic positioning unit and an excitation unit to stimulate vibrations of the eye. Sub-micrometer vibrations of the eye can be measured in-vivo with this system.

  14. Intraocular Implants for the Treatment of Autoimmune Uveitis

    PubMed Central

    Lee, Darren J.

    2015-01-01

    Uveitis is the third leading cause of blindness in developed countries. Currently, the most widely used treatment of non-infectious uveitis is corticosteroids. Posterior uveitis and macular edema can be treated with intraocular injection of corticosteroids, however, this is problematic in chronic cases because of the need for repeat injections. Another option is systemic immunosuppressive therapies that have their own undesirable side effects. These systemic therapies result in a widespread suppression of the entire immune system, leaving the patient susceptible to infection. Therefore, an effective localized treatment option is preferred. With the recent advances in bioengineering, biodegradable polymers that allow for a slow sustained-release of a medication. These advances have culminated in drug delivery implants that are food and drug administration (FDA) approved for the treatment of non-infectious uveitis. In this review, we discuss the types of ocular implants available and some of the polymers used, implants used for the treatment of non-infectious uveitis, and bioengineered alternatives that are on the horizon. PMID:26264035

  15. Determination of scattering in intraocular lenses by spectrophotometric measurements.

    PubMed

    Artigas, José M; Felipe, Adelina; Navea, Amparo; García-Domene, M Carmen; Pons, Álvaro; Mataix, Jorge

    2014-12-01

    This study presents a method for measuring scattering in explanted intraocular lenses (IOLs). Currently, determining scattering in IOLs is usually performed by Scheimpflug cameras and the results are expressed in the units used by this apparatus. The method we propose uses a spectrophotometer and this makes it possible to measure the total transmission of the IOL by using an integrating sphere; the direct transmission is determined by the double-beam mode. The difference between these two transmissions gives a value of the scattering in percentage values of light lost. In addition, by obtaining the spectral transmission curve, information about the most scattered wavelengths is also obtained. The IOL power introduces errors when directly measured, particularly with high powers. This problem can be overcome if a tailor-made cuvette is used that shortens the distance between the IOL and the condensing lens of the spectrophotometer when the IOL powers are below 24 diopters. We checked the effectiveness of this method by measuring the scattering of three explanted IOLs from cornea donors. This method, however, does not make it possible to ascertain whether the scattering measured is caused by surface light scattering or internal light scattering.

  16. Motorized injector-assisted intrascleral intraocular lens fixation.

    PubMed

    Hung, Jia-Horung; Wang, Shih-Hao; Teng, Yu-Ti; Hsu, Sheng-Min

    2017-03-01

    For eyes with deficient capsular support, intraocular lens (IOL) implantation has long been a technical challenge. Recently, intrascleral fixation of the haptics of a three-piece posterior chamber IOL has become a popular option. In this procedure, externalization of the leading haptic during IOL injection is a stressful step. We present a modified technique to improve the ease and safety of this step. Our modified technique involves IOL injection with a motorized injector with several important modifications described here. With these modifications, a surgeon can easily maintain the correct orientation of the IOL in a well-controlled manner during IOL injection. The records of 13 patients who underwent this technique were retrospectively evaluated. Corrected-distance visual acuity improved significantly after surgery (p<0.05). No postoperative retinal detachment, endophthalmitis, IOL decentration, or vitreous hemorrhage was noted during the follow-up period. In conclusion, the motorized injector-assisted intrascleral IOL fixation technique is a safe and effective alternative to the conventional procedure. This technique makes the process of leading haptic externalization easier and more controllable.

  17. Star testing: a novel evaluation of intraocular lens optical quality

    PubMed Central

    Mitchell, L; Molteno, A C B; Bevin, T H; Sanderson, G

    2006-01-01

    Background Despite the importance of optical quality of an intraocular lens (IOL) on visual outcomes following cataract surgery, objective data on their optical quality are not readily available, and manufacturing standards are industry regulated. The star test is a classic test of optical quality based on examination of the Airy disc and expanded diffraction rings of a point source of light, used mainly for telescope and microscope objectives. Methods A physical model eye cell allowed star testing of IOLs under conditions similar to the optical environment in which they operate. 18 IOLs were tested and results compared to actual images produced by these lenses in the model eye cell. Quantitative measures of star testing performance were developed. Results The optical performance of the IOLs varied, some performing very poorly. Most lenses (13/17) performed better in reverse orientation, while aberrations induced by the haptics of foldable IOLs were also detected. There was excellent correlation between actual images formed and star testing parameters. Conclusion Star testing IOLs was a novel biomedical application of a centuries old, inexpensive method. A concerning variation of optical quality was found, suggesting IOL optical performance data should be more readily available. Independent, authority mandated IOL optical quality standards should be developed, and results readily available to ophthalmologists. PMID:16622088

  18. Micro-optical imaging concepts for an intraocular vision aid

    NASA Astrophysics Data System (ADS)

    Eix, Ilos; Stork, Wilhelm; Muller-Glaser, Klaus D.

    2004-03-01

    About 10 million people around the world are suffering from blindness, where the path of light is disturbed due to an opaque, irreversible damaged, and inoperable cornea. Although vision is not given to this group of population, the retina is still intact. To date, there is no artificial implant which is able to replace the natural cornea. The work presented here describes an approach to build and implant a micro-optical and microelectronic system to be used as an intraocular vision aid. By overcoming the disturbed light path, it yields to an improved visual acuity of the patient. The main aspect of this bio-mimetic system is to transfer information representing the patient's field of view to the retina. An image of the field of view is captured in real-time outside the eye. After employing data processing, it is wireless transferred to the implanted part of the vision aid. From there, the information emerging from a micro display is imaged to the retina via a micro-optical system. The limited display resolution available inside the eye and the limited dimensions of the eyeball build the constrains of the optical system. A combination of a spatial light modulator together with an imaging lens system realizes intelligent spatial information distribution schemes onto the retina. This ensures a high outcome of visual acuity in the central region of the retina. Various retinal acuities can be realized. The employment of in-vivo adjustment mechanisms of the focal plane is discussed.

  19. Retinal images in the human eye with implanted intraocular lens

    NASA Astrophysics Data System (ADS)

    Zając, Marek; Siedlecki, Damian; Nowak, Jerzy

    2007-04-01

    A typical proceeding in cataract is based on the removal of opaque crystalline lens and inserting in its place the artificial intraocular lens (IOL). The quality of retinal image after such procedure depends, among others, on the parameters of the IOL, so the design of the implanted lens is of great importance. An appropriate choice of the IOL material, especially in relation to its biocompatibility, is often considered. However the parameter, which is often omitted during the IOL design is its chromatic aberration. In particular lack of its adequacy to the chromatic aberration of a crystalline lens may cause problems. In order to fit better chromatic aberration of the eye with implanted IOL to that of the healthy eye we propose a hybrid - refractive-diffractive IOL. It can be designed in such way that the total longitudinal chromatic aberration of an eye with implanted IOL equals the total longitudinal chromatic aberration of a healthy eye. In this study we compare the retinal image quality calculated numerically on the basis of the well known Liou-Brennan eye model with typical IOL implanted with that obtained if the IOL is done as hybrid (refractive-diffractive) design.

  20. Foldable antibacterial acrylic intraocular lenses of high refractive index.

    PubMed

    Parra, F; Vázquez, B; Benito, L; Barcenilla, J; San Román, J

    2009-11-09

    Hydrophilic copolymers with high refractive index and bactericide properties based on quaternary ammonium salts monomers and methacrylates bearing benzothiazole moieties have been developed for application as foldable intraocular lenses. Composition of the systems was adjusted to get materials with optimized flexibility, wettability, and refractive properties. All the materials have been characterized in terms of optical properties, glass transition temperature, water content, and wettability. Water contact values oscillated between 37 and 15% and refractive index values in the wet state between 1.49 and 1.53, depending on composition. Glass transition temperature interval was 63-77 degrees C. Values of surface free energy of the solid ranged from 49 to 54 mN/m, characteristic of IOL hydrogel materials. Bactericide properties of the quaternary ammonium salts methacrylates were higher than that of the benzothiazole derivative, showing inhibition halos as high as 23-25 mm in antibiogram tests against S. epidermidis and P. aeruginosa , strains found in the ocular cavity and responsible for most postsurgical endolphthalmitis. Biocompatibility of the systems was evaluated in cell cultures using human fibroblasts. Cellular viability was higher than 90%, and close to 100% in many cases, for the extracts of selected formulations collected at different periods of time.

  1. Effects of diurnal variation and anesthetic agents on intraocular pressure in Syrian hamsters (Mesocricetus auratus).

    PubMed

    Rajaei, Seyed Mehdi; Mood, Maneli Ansari; Paryani, Mohammad Reza; Williams, David L

    2017-01-01

    OBJECTIVE To determine effects of diurnal variation and anesthetic agents on intraocular pressure (IOP) in Syrian hamsters (Mesocricetus auratus). ANIMALS 90 healthy adult Syrian hamsters (45 males and 45 females). PROCEDURES IOP was measured with a rebound tonometer. In phase 1, IOP was measured in all hamsters 3 times during a 24-hour period (7 am, 3 pm, and 11 pm). In phase 2, hamsters were assigned to 5 groups (18 animals [9 males and 9 females]/group). Each group received an anesthetic agent or combination of anesthetic agents (ketamine hydrochloride, xylazine hydrochloride, diazepam, ketamine-diazepam [KD], or ketamine-xylazine [KX] groups) administered via the IP route. The IOP was measured before (time 0 [baseline]) and 10, 30, 60, 90, 120, and 150 minutes after administration of drugs. RESULTS Mean ± SD IOP values were 2.58 ± 0.87 mm Hg, 4.46 ± 1.58 mm Hg, and 5.96 ± 1.23 mm Hg at 7 am, 3 pm, and 11 pm, respectively. Mean baseline IOP was 6.25 ± 0.28 mm Hg, 6.12 ± 0.23 mm Hg, 5.75 ± 0.64 mm Hg, 5.12 ± 1.40 mm Hg, and 4.50 ± 1.30 mm Hg for the ketamine, xylazine, diazepam, KD, and KX groups, respectively. A significant decrease in IOP, compared with baseline IOP, was detected in only the KX group at 30, 60, and 90 minutes after drug administration. CONCLUSIONS AND CLINICAL RELEVANCE Maximum IOP in Syrian hamsters was detected at night. The ketamine-xylazine anesthetic combination significantly decreased IOP in Syrian hamsters.

  2. A comparative study of intraocular irrigating solutions: effects on electroretinography readings during closed vitrectomy in humans.

    PubMed

    Nao, N; Maruiwa, F; Nakazaki, S; Sawada, A

    1995-12-01

    The effects of intraocular irrigating solutions on electroretinography have been extensively studied in animal models, but effects on human electroretinography have not been reported. This study examined the effects of two commercially available irrigating solutions, S-MA2 (Opeguard MA) and DE-057 (BBS-Plus) on 30-Hz flicker electroretinography during closed vitrectomy in humans. Eight eyes of 8 patients were examined. All patients underwent a simple vitrectomy without treatment of proliferative membrane. For 30-Hz flicker electroretinography recording, a contact lens with a built-in light-emitting diode was sterilized and used as both a stimulus source and a recording electrode. Replacing S-MA2 with DE-057 decreased the electroretinography amplitude from 55.8 +/- 15.2 to 45.5 +/- 13.2 microV (mean +/- SEM). Changing the irrigation solution from DE-057 back to S-MA2 increased the amplitude from 45.5 +/- 13.2 to 59.9 +/- 17.3 microV. However, these changes were not statistically significant. Replacing S-MA2 with DE-057 significantly increased the peak time from 50.1 +/- 1.5 to 57.6 +/- 1.3 msec (p < 0.001). This change was reversible; after changing from DE-057 back to S-MA2, the peak time of flicker electroretinography significantly decreased from 57.6 +/- 1.3 to 49.0 +/- 2.1 msec (p < 0.01). Thus intraoperative 30-Hz electroretinography showed delayed peak time during irrigation with DE-057, as compared with S-MA2. The lower potassium concentration and higher glucose concentration of S-MA2, as compared with DE-057, may be the cause of such electroretinography changes.

  3. Relationship between Corneal Temperature and Intraocular Pressure in Healthy Individuals: A Clinical Thermographic Analysis

    PubMed Central

    Fabiani, Claudia; Li Voti, Roberto; Rusciano, Dario; Mutolo, Maria Giulia; Pescosolido, Nicola

    2016-01-01

    Purpose. To study the geographical distribution of corneal temperature (CT) and its influence on the intraocular pressure (IOP) of healthy human volunteers. Materials and Methods. Fifteen subjects (7 M, 8 F), 33.8 ± 17.4 years old, were enrolled in this pilot, cross-sectional study. Measurements of CT were taken after one hour with closed eyelids (CET) or closed eyelids with a cooling mask (cm-CET) and compared to baseline. Results. If compared to baseline, after CET, average CT significantly increased by 0.56°C in the RE and by 0.48°C in the LE (p < 0.001) and IOP concomitantly significantly increased by 1.13 mmHg and 1.46 mmHg, respectively, in each eye (p < 0.001). After cm-CET, average CT significantly decreased by 0.11°C and 0.20°C, respectively, in the RE and LE (RE p = 0.04; LE p = 0.024), followed by a significant IOP decrease of 2.19 mmHg and 1.54 mmHg, respectively, in each eye (RE p < 0.001; LE p = 0.0019). Conclusion. Significant variations of CT occurred after CET and cm-CET and were directly correlated with significant differences of IOP. It can be speculated that both oxidative stress and sympathetic nerve fiber stimulation by temperature oscillations may affect the regulation of AH vortex flow and turnover, thus influencing IOP values. PMID:26904273

  4. Relationship between homocysteine and intraocular pressure in men and women: A population-based study.

    PubMed

    Leibovitzh, Haim; Cohen, Eytan; Levi, Amos; Kramer, Michal; Shochat, Tzippy; Goldberg, Elad; Krause, Ilan

    2016-09-01

    The relationship between homocysteine levels and glaucoma has been questioned in previous studies without conclusive results. In the current study, we assessed the relationship between homocysteine levels and intraocular pressure which is one of the main factors in the development of glaucoma in men and women.A retrospective cross-sectional analysis of a database from a screening center in Israel which assessed 11,850 subjects, within an age range 20 to 80 years. The relationship between homocysteine and intraocular pressure has been investigated by comparing intraocular pressure in subjects with elevated and normal homocysteine and by comparing homocysteine levels in subjects with elevated and normal intraocular pressure. In addition, we compared the levels of homocysteine in subjects with and without a confirmed diagnosis of glaucoma.The mean IOP (±SD) in subjects with normal homocysteine levels(≤15 μmol/L) was 13.2 ± 2.3 mm Hg and 13.4 ± 2.4 mm Hg in those with high homocysteine levels (>15 μmol/L) (P < 0.008, 95% confidence interval [CI] 0.3-0.09).Nonetheless, after multivariate adjustment for age, gender, vitamin B12, and folic acid statistical significance was no longer demonstrated (P = 0.37). Mean homocysteine levels (±SD) in subjects with normal intraocular pressure of ≤ 21 mm Hg was 11.7 ± 5.5 μmol/L and 12.09 ± 3.43 μmol/L in those with elevated intraocular pressure (P = 0.4, 95%CI 1.1-1.8). Mean homocysteine levels (±SD) in subjects with glaucoma were 11.2 ± 3.5 μmol/L compared to 11.7 ± 5.5 μmol/L in subjects without glaucoma and normal intraocular pressure ≤ 21 mm Hg (P = 0.4, 95% CI 1.2-2.1).The current study displays no clinical correlation between the homocysteine level and the intraocular pressure. Homocysteine may not be used as a predictive parameter to recognize those subjects prone to develop elevated intraocular pressure.

  5. 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

  6. The effect of intraocular and intracranial pressure on retinal structure and function in rats

    PubMed Central

    Zhao, Da; He, Zheng; Vingrys, Algis J; Bui, Bang V; Nguyen, Christine T O

    2015-01-01

    An increasing number of studies indicate that the optic nerve head of the eye is sensitive not only to changes in intraocular pressure (IOP), but also to intracranial pressure (ICP). This study examines changes to optic nerve and retinal structure in a rat model in response to a range of IOP and ICP levels using optical coherence tomography. Furthermore, we examine the functional sequelae of these structural changes by quantifying the effect of pressure changes on the electroretinogram. IOP elevation (10–90 mmHg) induces progressive deformation of the optic nerve head and retinal surface (P < 0.05), compression of the retina (P < 0.05) and bipolar cell (b-wave), and retinal ganglion cell (scotopic threshold response) dysfunction (P < 0.05). Simultaneously altering ICP (−5 to 30 mmHg) modifies these IOP-induced responses, with lower ICP (−5 mmHg) exacerbating and higher ICP (15–30 mmHg) ameliorating structural and functional deficits. Thus, the balance between IOP and ICP (optic nerve pressure gradient, ONPG = IOP − ICP) plays an important role in optic nerve integrity. Structural and functional parameters exhibit a two-phase relationship to ONPG, with structural changes being more sensitive to ONPG modification (threshold = −0.6 to 11.3 mmHg) compared with functional changes (threshold = 49.7–54.6 mmHg). These findings have implications for diseases including glaucoma, intracranial hypertension, and long-term exposure to microgravity. PMID:26290528

  7. Materials for intraocular lenses enabling photo-controlled tuning of focal length in vivo

    NASA Astrophysics Data System (ADS)

    Träger, Jens; Heinzer, Jasmin; Kim, Hee-Cheol; Hampp, Norbert

    2007-07-01

    Typical postoperative complications in cataract surgery are that refractive power and curvature of the implanted intraocular lens (IOL) do not have optimum values, requiring the patient to wear viewing aids. This is mainly because biometric data relevant for calculation of the IOL's shape cannot be determined with the required precision. Hence, there is a need for methods to tune the focal length postoperatively in a non-invasive manner. We have developed polymers where we can induce a change in refractive index by linking or cleaving bonds between a su.ciently large number of side groups of the polymer main chain in a photoinduced cycloaddition or cycloreversion reaction, respectively. These photoreactions lead to a change in refractive index great enough to be interesting for the concept of in vivo tunable IOL's. The photochemical reaction can be triggered by a two-photon process (TPA) using a pulsed laser system, i.e. the energy required for bond breaking is provided by two photons in the visible range. This is important because light in the UV cannot induce undesired changes of the refractive index owing to the strong UV-absorption of the cornea. Undesired changes due to light in the visible range of the spectrum are unlikely to happen because photon density of sun light is much too low for TPA. Due to the excellent spatial resolution that can be achieved with two-photon processes one cannot only modify the refractive index of the entire lens but also selectively in well defined areas enabling to correct for aberrations such as astigmatism. Here, we present new polymers that do not only exhibit a photo induced change of refractive index great enough to induce a change of focal length of more than two diopters in a standard IOL. These new polymers have also significantly improved material properties with respect to the fabrication of the IOL and the TPA-sensitivities and the light energy required to induce the refractive index change.

  8. Removal of Silicone Oil From Intraocular Lens Using Novel Surgical Materials

    PubMed Central

    Paschalis, Eleftherios I.; Eliott, Dean; Vavvas, Demetrios G.

    2014-01-01

    Purpose To design, fabricate, and evaluate novel materials to remove silicone oil (SiO) droplets from intraocular lenses (IOL) during vitreoretinal surgery. Methods Three different designs were fabricated using soft lithography of polydimethylsiloxane (PDMS), three-dimensional (3D) inverse PDMS fabrication using water dissolvable particles, and atomic layer deposition (ALD) of alumina (Al2O3) on surgical cellulose fibers. Laboratory tests included static and dynamic contact angle (CA) measurements with water and SiO, nondestructive x-ray microcomputer tomography (micro-CT), and microscopy. SiO removal was performed in vitro and ex vivo using implantable IOLs and explanted porcine eyes. Results All designs exhibited enhanced hydrophobicity and oleophilicity. Static CA measurements with water ranged from 131° to 160° and with SiO CA approximately 0° in 120 seconds following exposure. Nondestructive x-ray analysis of the 3D PDMS showed presence of interconnected polydispersed porosity of 100 to 300 μm in diameter. SiO removal from IOLs was achieved in vitro and ex vivo using standard 20-G vitrectomy instrumentation. Conclusion Removal of SiO from IOLs can be achieved using materials with lower surface energy than that of the IOLs. This can be achieved using appropriate surface chemistry and surface topography. Three designs, with enhanced hydrophobic properties, were fabricated and tested in vitro and ex vivo. All materials remove SiO within an aqueous environment. Preliminary ex vivo results were very promising, opening new possibilities for SiO removal in vitreoretinal surgeries. Translational Relevance This is the first report of an instrument that can lead to successful removal of SiO from the surface of IOL. In addition to the use of this instrument/material in medicine it can also be used in the industry, for example, retrieval of oil spills from bodies of water. PMID:25237593

  9. Quantitative Assessment of the Impact of Blood Pulsation on Intraocular Pressure Measurement Results in Healthy Subjects

    PubMed Central

    2017-01-01

    Background. Blood pulsation affects the results obtained using various medical devices in many different ways. Method. The paper proves the effect of blood pulsation on intraocular pressure measurements. Six measurements for each of the 10 healthy subjects were performed in various phases of blood pulsation. A total of 8400 corneal deformation images were recorded. The results of intraocular pressure measurements were related to the results of heartbeat phases measured with a pulse oximeter placed on the index finger of the subject's left hand. Results. The correlation between the heartbeat phase measured with a pulse oximeter and intraocular pressure is 0.69 ± 0.26 (p < 0.05). The phase shift calculated for the maximum correlation is equal to 60 ± 40° (p < 0.05). When the moment of measuring intraocular pressure with an air-puff tonometer is not synchronized, the changes in IOP for the analysed group of subjects can vary in the range of ±2.31 mmHg (p < 0.3). Conclusions. Blood pulsation has a statistically significant effect on the results of intraocular pressure measurement. For this reason, in modern ophthalmic devices, the measurement should be synchronized with the heartbeat phases. The paper proposes an additional method for synchronizing the time of pressure measurement with the blood pulsation phase. PMID:28250983

  10. Intraocular pressure in captive American flamingos (Phoenicopterus ruber) as measured by rebound tonometry.

    PubMed

    Molter, Christine M; Hollingsworth, Steven R; Kass, Philip H; Chinnadurai, Sathya K; Wack, Raymund F

    2014-09-01

    Intraocular pressure was measured using rebound tonometry in American flamingos (Phoenicopterus ruber), with the head in an upright standing position and when lowered in a feeding position, to establish a reference range. Mean +/- standard deviation (SD) (range) intraocular pressure for flamingos with the head in an upright position was right eye (OD)= 10.9 +/- 1.8 mm Hg (7-15 mm Hg) and left eye (OS) = 11.1 +/- 2.3 mm Hg (8-21 mm Hg). Median intraocular pressure for flamingos with the head in an upright position was OD and OS = 11 mm Hg. Mean intraocular pressure for flamingos with the head in a feeding position was OD = 14.3 +/- 2.5 mm Hg (10-22 mm Hg) and OS = 14.4 +/- 2.7 mm Hg (11-24 mm Hg), which were significantly higher. Median intraocular pressure for flamingos with the head in a feeding position was OD and OS = 14 mm Hg.

  11. Intraocular pressure and glaucoma: Is physical exercise beneficial or a risk?

    PubMed

    McMonnies, Charles William

    2016-01-01

    Intraocular pressure may become elevated with muscle exertion, changes in body position and increased respiratory volumes, especially when Valsalva manoeuver mechanisms are involved. All of these factors may be present during physical exercise, especially if hydration levels are increased. This review examines the evidence for intraocular pressure changes during and after physical exercise. Intraocular pressure elevation may result in a reduction in ocular perfusion pressure with the associated possibility of mechanical and/or ischaemic damage to the optic nerve head. A key consideration is the possibility that, rather than being beneficial for patients who are susceptible to glaucomatous pathology, any intraocular pressure elevation could be detrimental. Lower intraocular pressure after exercise may result from its elevation causing accelerated aqueous outflow during exercise. Also examined is the possibility that people who have lower frailty are more likely to exercise as well as less likely to have or develop glaucoma. Consequently, lower prevalence of glaucoma would be expected among people who exercise. The evidence base for this topic is deficient and would be greatly improved by the availability of tonometry assessment during dynamic exercise, more studies which control for hydration levels, and methods for assessing the potential general health benefits of exercise against any possibility of exacerbated glaucomatous pathology for individual patients who are susceptible to such changes.

  12. Schur monotone decreasing sequences

    NASA Astrophysics Data System (ADS)

    Ganikhodjaev, Rasul; Saburov, Mansoor; Saburov, Khikmat

    2013-09-01

    In this paper, we introduce Schur monotone decreasing sequences in an n-dimensional space by considering a majorization pre-order. By means of down arrow mappings, we study omega limiting points of bounded Schur monotone decreasing sequences. We provide convergence criteria for such kinds of sequences. We prove that a Cesaro mean (or an arithmetic mean) of any bounded Schur monotone decreasing sequences converges to a unique limiting point.

  13. Mirtogenol® potentiates latanoprost in lowering intraocular pressure and improves ocular blood flow in asymptomatic subjects

    PubMed Central

    Steigerwalt, Robert D; Belcaro, Gianni; Morazzoni, Paolo; Bombardelli, Ezio; Burki, Carolina; Schönlau, Frank

    2010-01-01

    Purpose: The dietary supplement Mirtogenol® was previously shown to lower elevated intraocular pressure (IOP). We here present the effects of this supplement on IOP in comparison as well as in combination with latanoprost eye drops. Methods: Seventy-nine patients with asymptomatic ocular hypertension were randomly assigned to three groups receiving either the supplement, or latanoprost eye drops, or both in combination. Intraocular pressure and retinal blood flow were investigated in monthly intervals over 24 weeks. Results: Mirtogenol alone lowered IOP from baseline 38.1 to 29.0 mmHg after 16 weeks, with little further improvement during the following eight weeks. Latanoprost rapidly lowered IOP from baseline 37.7 to 27.2 mmHg within four weeks, without further effects thereafter. The combination of the supplement and latanoprost lowered IOP from 38.0 to 27.3 mmHg after four weeks, and further decreased IOP to 24.2 mmHg after six weeks. After 24 weeks IOP with the combination treatment (23.0 mmHg) was significantly lower than with latanoprost alone (27.2 mmHg). Mirtogenol and latanoprost individually showed comparable effects for gradually increasing central artery blood flow with treatment duration. Combination treatment showed higher systolic blood flow velocity throughout the trial period. The diastolic blood flow velocity gradually increased with treatment duration in all three groups. From twelve weeks onwards, the diastolic component with combination treatment was higher than with individual treatments. Conclusions: Mirtogenol lowered elevated IOP in patients almost as effectively as latanoprost, however, it takes much longer (24 vs 4 weeks). The combination of both was more effective for lowering IOP and the combination yielded better retinal blood flow. No serious side effects occurred during the study, apart from standard side effects in patients related to Latanoprost. These promising results warrant further research of Mirtogenol with a larger patient

  14. Management of mydriasis and pain in cataract and intraocular lens surgery: review of current medications and future directions

    PubMed Central

    Grob, Seanna R; Gonzalez-Gonzalez, Luis A; Daly, Mary K

    2014-01-01

    The maintenance of mydriasis and the control of postoperative pain and inflammation are critical to the safety and success of cataract and intraocular lens replacement surgery. Appropriate mydriasis is usually achieved by topical and/or intracameral administration of anticholinergic agents, sympathomimetic agents, or both, with the most commonly used being cyclopentolate, tropicamide, and phenylephrine. Ocular inflammation is common after cataract surgery. Topical steroids and nonsteroidal anti-inflammatory drugs are widely used because they have been proved effective to control postsurgical inflammation and decrease pain. Topical nonsteroidal anti-inflammatory drugs have also been shown to help maintain dilation. However, use of multiple preoperative drops for pupil dilation, inflammation, and pain control have been shown to be time consuming, resulting in delays to the operating room, and they cause dissatisfaction among perioperative personnel; their use can also be associated with systemic side effects. Therefore, ophthalmologists have been in search of new options to streamline this process. This article will review the current medications commonly used for intraoperative mydriasis, as well as pain and inflammation control. In addition, a new combination of ketorolac, an anti-inflammatory agent, and phenylephrine, a mydriatic agent has recently been designed to maintain intraoperative mydriasis and to reduce postoperative pain and irritation from intraocular lens replacement surgery. Two Phase III clinical trials evaluating this combination have demonstrated statistically significant differences when compared to placebo in maintaining intraoperative mydriasis (P<0.00001) and in reducing pain in the early postoperative period (P=0.0002). This medication may be of benefit for use in cataract and lens replacement surgery in the near future. PMID:25061276

  15. Long-term heavy silicone oil intraocular tamponade.

    PubMed

    Dooley, Ian J; Duignan, Emma S; Kilmartin, Dara J

    2016-02-01

    Heavy silicone oil tamponade is intended to be temporary, but may occasionally be indefinite in patients who refuse, or are deemed unsuitable for, further surgery. The aim of this study is to compare the outcomes of patients with temporary versus indefinite heavy silicone oil intraocular tamponade. This retrospective, comparative case series identified 75 patients who underwent heavy silicone oil instillation (Oxane HD) over a 6 year period (2006-2012) in one institution. Thirty-nine patients had temporary heavy oil tamponade and 36 patients had indefinite tamponade. The majority (68 %) of patients had a history of previous vitreoretinal surgery prior to oil instillation and 66.7 % had pre-existing proliferative vitreoretinopathy (PVR). The mean final logMAR best corrected visual acuity (BCVA) was significantly better in the temporary tamponade group (1.34 ± 0.66) than the indefinite tamponade group 1.82 ± 0.64 (p = 0.003). Ambulatory BCVA (≥ 4/200) was retained in 76.3 % of temporary tamponade patients versus 54.3 % of indefinite tamponade patients (p = 0.093). Successful retinal reattachment was significantly more likely in temporary tamponade patients (92.3 %) than indefinite tamponade patients (75 %; p = 0.04). Complications in the patients with indefinite heavy silicone oil tamponade included redetachment (38.9 %), corneal pathology (13.8 %), secondary glaucoma (11.1 %) and anterior segment emulsification (8.3 %).While temporary tamponade patients had better outcomes than those with indefinite tamponade, the majority of indefinite tamponade patients still retained ambulatory vision in the affected eye. Indefinite heavy silicone oil tamponade remains a viable option for those who cannot undergo removal of oil surgery.

  16. Energy Efficiency of a New Trifocal Intraocular Lens

    NASA Astrophysics Data System (ADS)

    Vega, F.; Alba-Bueno, F.; Millán, M. S.

    2014-01-01

    The light distribution among the far, intermediate and near foci of a new trifocal intraocular lens (IOL) is experimentally determined, as a function of the pupil size, from image analysis. The concept of focus energy efficiency is introduced because, in addition to the theoretical diffraction efficiency of the focus, it accounts for other factors that are naturally presented in the human eye such as the level of spherical aberration (SA) upon the IOL, light scattering at the diffractive steps or the depth of focus. The trifocal IOL is tested in-vitro in two eye models: the aberration-free ISO model, and a so called modified-ISO one that uses an artificial cornea with positive spherical SA in instead. The SA upon the IOL is measured with a Hartmann-Shack sensor and compared to the values of theoretical eye models. The results show, for large pupils, a notorious reduction of the energy efficiency of the far and near foci of the trifocal IOL due to two facts: the level of SA upon the IOL is larger than the value the lens is able to compensate for and there is significant light scattering at the diffractive steps. On the other hand, the energy efficiency of the intermediate focus for small pupils is enhanced by the contribution of the extended depth of focus of the near and far foci. Thus, while IOLs manufacturers tend to provide just the theoretical diffraction efficiency of the foci to show which would be the performance of the lens in terms of light distribution among the foci, our results put into evidence that this is better described by using the energy efficiency of the foci.

  17. Retreatments after multifocal intraocular lens implantation: an analysis

    PubMed Central

    Gundersen, Kjell Gunnar; Makari, Sarah; Ostenstad, Steffen; Potvin, Rick

    2016-01-01

    Purpose To determine the incidence and etiology of required retreatment after multifocal intraocular lens (IOL) implantation and to evaluate the methods and clinical outcomes of retreatment. Patients and methods A retrospective chart review of 416 eyes of 209 patients from one site that underwent uncomplicated cataract surgery with multifocal IOL implantation. Biometry, the IOL, and refractive data were recorded after the original implantation, with the same data recorded after retreatment. Comments related to vision were obtained both before and after retreatment for retreated patients. Results The multifocal retreatment rate was 10.8% (45/416 eyes). The eyes that required retreatment had significantly higher residual refractive astigmatism compared with those who did not require retreatment (1.21±0.51 D vs 0.51±0.39 D, P<0.01). The retreatment rate for the two most commonly implanted primary IOLs, blended bifocal (10.5%, 16/152) and bilateral trifocal (6.9%, 14/202) IOLs, was not statistically significantly different (P=0.12). In those requiring retreatment, refractive-related complaints were most common. Retreatment with refractive corneal surgery, in 11% of the eyes, and piggyback IOLs, in 89% of the eyes, was similarly successful, improving patient complaints 78% of the time. Conclusion Complaints related to ametropia were the main reasons for retreatment. Residual astigmatism appears to be an important determinant of retreatment rate after multifocal IOL implantation. Retreatment can improve symptoms for a high percentage of patients; a piggyback IOL is a viable retreatment option. PMID:27041983

  18. Heavy silicone oil: a "novel" intraocular tamponade agent.

    PubMed

    Cazabon, Sunildath; Hillier, Roxane J; Wong, David

    2011-06-01

    Advances in vitreoretinal surgery have greatly increased the anatomical re-attachment rate in cases with proliferative vitreoretinopathy. Intraocular tamponade agents have been in use by vitreoretinal surgeons for nearly a century. The effectiveness of an internal agent relies on its ability to make contact with the internal surface of the vitreous cavity. In the short term, this is controlled by the agent's specific gravity and interfacial tensions. In the long term, the viscosity of the material is critical to maintaining its integrity and thus reducing dispersion. The commonly used tamponade agents such as perfluoropropane (C3F8), sulfur hexafluoride (SF6), and silicone oil are "lighter than water" hence, float upward in the aqueous. A consequence of this is that in the upright position the superior retina is very well supported, leaving the inferior retina less well so. More recently, there has been interest in the development of "heavier than water" long-term tamponade agents that sink in the eye. Heavy silicone oil is a transparent, homogenous solution of two substances used as a single tamponade agent with improved properties and a specific gravity greater than water. Densiron (one of the two available heavy silicone oil's) is a mixture of perfluorohexyloctane (F6H8, with a specific gravity of 1.35 g/ml and viscosity of 2.5 mPas), and conventional silicone oil (specific gravity of 0.97 g/ml and viscosity of 5700 mPas depending on the molecular weight). The specific gravity of Densiron is 1.06 g/ml and the viscosity is 1400 mPas, making it a novel heavier-than-water, long-term internal tamponade agent, which means that in the upright position it sinks and provides support for the inferior retina.

  19. Nanosponge-Mediated Drug Delivery Lowers Intraocular Pressure

    PubMed Central

    Lambert, Wendi S.; Carlson, Brian J.; van der Ende, Alice E.; Shih, Grace; Dobish, Julia N.; Calkins, David J.; Harth, Eva

    2015-01-01

    Purpose We examined the efficacy of an extended-release drug delivery system, nanosponge (NS) encapsulated compounds, administered intravitreally to lower intraocular pressure (IOP) in mice. Methods Bilateral ocular hypertension was induced in mice by injecting microbeads into the anterior chamber. Hypertensive mice received NS loaded with ocular hypotensive drugs via intravitreal injection and IOP was monitored. Retinal deposition and retinal ganglion cell (RGC) uptake of Neuro-DiO were examined following intravitreal injection of Neuro-DiO-NS using confocal microscopy. Results Brimonidine-loaded NS lowered IOP 12% to 30% for up to 6 days (P < 0.02), whereas travoprost-NS lowered IOP 19% to 29% for up to 4 days (P < 0.02) compared to saline injection. Three bimatoprost NS were tested: a 400-nm NS and two 700-nm NS with amorphous (A-NS) or amorphous/crystalline (AC-NS) crosslinkers. A single injection of 400 nm NS lowered IOP 24% to 33% for up to 17 days compared to saline, while A-NS and AC-NS lowered IOP 22% to 32% and 18% to 26%, respectively, for up to 32 days (P < 0.046). Over time retinal deposition of Neuro-DiO increased from 19% to 71%; Neuro-DiO released from NS was internalized by RGCs. Conclusions A single injection of NS can effectively deliver ocular hypotensive drugs in a linear and continuous manner for up to 32 days. Also, NS may be effective at targeting RGCs, the neurons that degenerate in glaucoma. Translational Relevance Patient compliance is a major issue in glaucoma. The use of NS to deliver a controlled, sustained release of therapeutics could drastically reduce the number of patients that progress to vision loss in this disease. PMID:25599009

  20. Psychophysical Vision Simulation of Diffractive Bifocal and Trifocal Intraocular Lenses

    PubMed Central

    Brezna, Wolfgang; Lux, Kirsten; Dragostinoff, Nikolaus; Krutzler, Christian; Plank, Nicole; Tobisch, Rainer; Boltz, Agnes; Garhöfer, Gerhard; Told, Reinhard; Witkowska, Katarzyna; Schmetterer, Leopold

    2016-01-01

    Purpose The visual performance of monofocal, bifocal, and trifocal intraocular lenses was evaluated by human individuals using a vision simulator device. This allowed investigation of the visual impression after cataract surgery, without the need actually to implant the lenses. Methods The randomized, double-masked, three-way cross-over study was conducted on 60 healthy male and female subjects aged between 18 and 35 years. Visual acuity (Early Treatment Diabetic Retinopathy Study; ETDRS) and contrast sensitivity tests (Pelli-Robson) under different lighting conditions (luminosities from 0.14–55 cd/m2, mesopic to photopic) were performed at different distances. Results Visual acuity tests showed no difference for corrected distance visual acuity data of bi- and trifocal lens prototypes (P = 0.851), but better results for the trifocal than for the bifocal lenses at distance corrected intermediate (P = 0.021) and distance corrected near visual acuity (P = 0.044). Contrast sensitivity showed no differences between bifocal and trifocal lenses at the distant (P = 0.984) and at the near position (P = 0.925), but better results for the trifocal lens at the intermediate position (P = 0.043). Visual acuity and contrast sensitivity showed a strong dependence on luminosity (P < 0.001). Conclusions At all investigated distances and all lighting conditions, the trifocal lens prototype often performed better, but never worse than the bifocal lens prototype. Translational Relevance The vision simulator can fill the gap between preclinical lens development and implantation studies by providing information of the perceived vision quality after cataract surgery without implantation. This can reduce implantation risks and promotes the development of new lens concepts due to the cost effective test procedure. PMID:27777828

  1. Effects of ethacrynic acid on intraocular pressure of anesthetized rats.

    PubMed

    Searles, R V; Johnson, M; Shikher, V; Balaban, C D; Severs, W B

    1999-03-01

    Ethacrynic acid (ECA) lowers intraocular pressure (i.o.p.) by an effect usually ascribed to increased drainage of aqueous humor by the trabecular meshwork. Here, we describe the effects of a continuous 2-hr intracameral infusion of balanced salt solution (BSS), with or without 2 mM ECA (sodium salt), on IOP of pentobarbital anesthetized rats. The infusion was divided into a constant (0.05 microliter/min) and a periodic (0.25 microliter/min) component that cycled 4 min on then 4 min off. This permitted the calculation of dynamic changes in resistive (trabecular and uveoslceral drainage) and nonresistive (aqueous synthesis, episcleral venous pressure) components of IOP by fitting a second-order transfer function to the responses. ECA markedly blunted the BSS-induced rise in IOP (P < 0.01). The rise in resistive mechanisms (ocular impedance) was transiently blunted by ECA (P < 0.05) during the third and fourth 8-min cycles, and nonresistive mechanisms were reduced by ECA from cycles 3-10 (P < 0.05). Then, at the end of the infusion, the control and ECA dynamic values were similar (P < 0.05), although IOP of ECA-treated rats was still slightly reduced (P < 0.05). The most likely explanation is a summation of small changes in both resistive and nonresistive components of IOP dynamics. Systemic blood pressure was unchanged within either group. The well-known effects of ECA on the trabecular meshwork, alone, are insufficient to explain the dynamic changes in IOP observed in this model.

  2. Intraocular pressure following ECCE and IOL implantation in patients with glaucoma.

    PubMed

    Kooner, K S; Dulaney, D D; Zimmerman, T J

    1988-08-01

    Patients with glaucoma may suffer optic nerve head damage due to elevated intraocular pressure (IOP) after any intraocular procedure. We retrospectively reviewed the IOP data in 82 consecutive patients (103 eyes) with glaucoma after extracapsular cataract extraction (ECCE) and posterior chamber intraocular lens (PC-IOL) implantation. Nine eyes had previous trabeculectomy and three eyes required combined trabeculectomy with ECCE and PC-IOL. The average follow-up period is 1.5 years (range 0.5 to 6 years). The postoperative IOP rise of 8 mm Hg over baseline or above 23 mm Hg was observed in 45 eyes (49.5%). Two eyes needed argon laser trabeculoplasty and one required trabeculectomy to control postoperative IOP elevation. Most of the patients required the same or lesser number of medications for IOP control after surgery. Results suggest that ECCE with PC-IOL may be a relatively safe procedure in cataract patients with preexisting glaucoma.

  3. [Intraocular lenses for the correction of refraction errors. Part 1: phakic anterior chamber lenses].

    PubMed

    Kohnen, T; Baumeister, M; Cichocki, M

    2005-10-01

    In this overview, the current status of intraocular lens surgery to correct refractive error is reviewed. The interventions are divided into additive surgery with intraocular lens implantation without extraction of the crystalline lens (phakic intraocular lens, PIOL) or the removal of the crystalline lens with implantation of an IOL (refractive lens exchange, RLE). Phakic IOLs are constructed as angle-supported or iris-fixated anterior chamber lenses and posterior chamber lenses that are fixated in the ciliary sulcus. The implantation of phakic IOLs has been demonstrated to be an effective, safe, predictable and stable procedure to correct higher refractive errors. Complications are rare and differ for the three types of PIOL; for anterior chamber lenses these are mainly pupil ovalization and endothelial cell loss.

  4. Influence of untreated chronic plastic iridocyclitis on intraocular pressure in leprosy patients.

    PubMed

    Karaçorlu, M A; Cakiner, T; Saylan, T

    1991-02-01

    The intraocular pressures of a total of 286 eyes of patients with lepromatous and borderline lepromatous leprosy who never had regular ophthalmological care or local eye treatment were measured. The patients were categorised according to the type of leprosy they had, and the eyes were categorised as without or with chronic plastic iridocyclitis. In patients with lepromatous and borderline lepromatous types of leprosy the intraocular pressure was significantly lower in eyes with chronic plastic iridocylitis 10.1 (3.6) mmHg than in both unaffected eyes 11.0 (3.2) mmHg and control eyes 13.5 (2.5) mmHg. It has been shown that chronic plastic iridocyclitis which remains untreated for years results in a lower intraocular pressure than normal.

  5. Influence of untreated chronic plastic iridocyclitis on intraocular pressure in leprosy patients.

    PubMed Central

    Karaçorlu, M A; Cakiner, T; Saylan, T

    1991-01-01

    The intraocular pressures of a total of 286 eyes of patients with lepromatous and borderline lepromatous leprosy who never had regular ophthalmological care or local eye treatment were measured. The patients were categorised according to the type of leprosy they had, and the eyes were categorised as without or with chronic plastic iridocyclitis. In patients with lepromatous and borderline lepromatous types of leprosy the intraocular pressure was significantly lower in eyes with chronic plastic iridocylitis 10.1 (3.6) mmHg than in both unaffected eyes 11.0 (3.2) mmHg and control eyes 13.5 (2.5) mmHg. It has been shown that chronic plastic iridocyclitis which remains untreated for years results in a lower intraocular pressure than normal. PMID:1995040

  6. Functional diversity exhibits a diverse relationship with area, even a decreasing one.

    PubMed

    Karadimou, Elpida K; Kallimanis, Athanasios S; Tsiripidis, Ioannis; Dimopoulos, Panayotis

    2016-10-18

    The relationship between species richness and area is one of the few well-established laws in ecology, and one might expect a similar relationship with functional diversity (FD). However, only a few studies investigate the relationship between trait-based FD and area, the Functional Diversity - Area Relationship (FDAR). To examine FDAR, we constructed the species accumulation curve and the corresponding FD curve. We used plant diversity data from nested plots (1-128 m(2)), recorded on the Volcanic islands of Santorini Archipelagos, Greece. Six multidimensional FD indices were calculated using 26 traits. We identified a typology of FDARs depending on the facet of FD analyzed: (A) strongly positive for indices quantifying the range of functional traits in the community, (B) negative correlation for indices quantifying the evenness in the distribution of abundance in the trait space, (C) no clear pattern for indices reflecting the functional similarity of species and (D) idiosyncratic patterns with area for functional divergence. As area increases, the range of traits observed in the community increases, but the abundance of traits does not increase proportionally and some traits become dominant, implying a reliance on some functions that may be located in either the center or the periphery of the trait space.

  7. Functional diversity exhibits a diverse relationship with area, even a decreasing one

    PubMed Central

    Karadimou, Elpida K.; Kallimanis, Athanasios S.; Tsiripidis, Ioannis; Dimopoulos, Panayotis

    2016-01-01

    The relationship between species richness and area is one of the few well-established laws in ecology, and one might expect a similar relationship with functional diversity (FD). However, only a few studies investigate the relationship between trait-based FD and area, the Functional Diversity - Area Relationship (FDAR). To examine FDAR, we constructed the species accumulation curve and the corresponding FD curve. We used plant diversity data from nested plots (1–128 m2), recorded on the Volcanic islands of Santorini Archipelagos, Greece. Six multidimensional FD indices were calculated using 26 traits. We identified a typology of FDARs depending on the facet of FD analyzed: (A) strongly positive for indices quantifying the range of functional traits in the community, (B) negative correlation for indices quantifying the evenness in the distribution of abundance in the trait space, (C) no clear pattern for indices reflecting the functional similarity of species and (D) idiosyncratic patterns with area for functional divergence. As area increases, the range of traits observed in the community increases, but the abundance of traits does not increase proportionally and some traits become dominant, implying a reliance on some functions that may be located in either the center or the periphery of the trait space. PMID:27752086

  8. Bulls grazing Kentucky 31 tall fescue exhibit impaired growth, semen quality, and decreased semen freezing potential

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Serum prolactin (PRL) and testosterone concentrations, body weight, body composition, semen quality, and semen freezing potential for bulls grazing the toxic tall fescue (Lolium arundinaceum [Schreb.] Darbysh. ¼ Schedonorous arundinaceum [Schreb.] Dumort.) cultivar Kentucky 31 (E+) compared with a n...

  9. Large holograms in traveling exhibitions

    NASA Astrophysics Data System (ADS)

    Christakis, Anne-Marie

    1994-01-01

    The presentation of large holograms in travelling exhibitions has always posed problems, mainly due to lack of space. The Museum of Holography was consequently required to develop, with Jean-Francois Moreau, display consoles which are light, affordable and completely detachable. In a permanent exposition at the Forum des Halles in Paris, the Museum displays a room with 22 holograms, each measuring 1 m X 1 m, in a structure designed by the architect Fabien Vienne. The different systems used by the Museum are presented here.

  10. Symbolic algebra approach to the calculation of intraocular lens power following cataract surgery

    NASA Astrophysics Data System (ADS)

    Hjelmstad, David P.; Sayegh, Samir I.

    2013-03-01

    We present a symbolic approach based on matrix methods that allows for the analysis and computation of intraocular lens power following cataract surgery. We extend the basic matrix approach corresponding to paraxial optics to include astigmatism and other aberrations. The symbolic approach allows for a refined analysis of the potential sources of errors ("refractive surprises"). We demonstrate the computation of lens powers including toric lenses that correct for both defocus (myopia, hyperopia) and astigmatism. A specific implementation in Mathematica allows an elegant and powerful method for the design and analysis of these intraocular lenses.

  11. Siderosis bulbi as a consequence of a missed intraocular foreign body

    PubMed Central

    Lapira, Matthew; Karl, David; Murgatroyd, Helen

    2014-01-01

    We present a case of a 56-year-old man who suffered an injury to his right eye in June 2012. He presented to an emergency department, however, the presence of a penetrating injury and an intraocular foreign body was not identified. A year later he was referred to the ophthalmology department due to reduced vision and change of iris colour in the same eye. Examination revealed clinical signs consistent with a previous penetrating injury and a retained ferrous intraocular foreign body. PMID:24459228

  12. Relationship between Glaucoma Drainage Device Size and Intraocular Pressure Control: Does Size Matter?

    PubMed Central

    Rodgers, Cooper D; Meyer, Alissa M

    2017-01-01

    ABSTRACT There is ambiguity in the literature regarding whether a larger glaucoma drainage device (GDD) achieves a lower long-term intraocular pressure (IOP). There is some evidence on both sides, but overall there seems to be an optimal surface area of approximately 200-250 mm2 beyond which there may be little advantage to increasing the plate size for most patients. How to cite this article Rodgers CD, Meyer AM, Sherwood MB. Relationship between Glaucoma Drainage Device Size and Intraocular Pressure Control: Does Size Matter? J Curr Glaucoma Pract 2017;11(1):1-2. PMID:28138210

  13. Apparatus and method for non-contact, acoustic resonance determination of intraocular pressure

    DOEpatents

    Sinha, Dipen N.; Wray, William O.

    1994-01-01

    Apparatus and method for measuring intraocular pressure changes in an eye under investigation by detection of vibrational resonances therein. An ultrasonic transducer operating at its resonant frequency is amplitude modulated and swept over a range of audio frequencies in which human eyes will resonate. The output therefrom is focused onto the eye under investigation, and the resonant vibrations of the eye observed using a fiber-optic reflection vibration sensor. Since the resonant frequency of the eye is dependent on the pressure therein, changes in intraocular pressure may readily be determined after a baseline pressure is established.

  14. In-the-bag nasal intraocular lens optic truncation for treatment of negative dysphotopsia.

    PubMed

    Alapati, Neeti Meghnad; Harocopos, George J; Sheybani, Arsham

    2016-12-01

    We describe in-the-bag nasal intraocular lens (IOL) optic truncation, a new technique for the treatment of negative dysphotopsia. After a plane is created between the nasal capsular bag and the IOL, micrograspers and intraocular scissors are used to amputate the nasal optic edge. The amputation is to reduce the optical impact of the IOL edge and nasal anterior capsule on the occurrence of negative dysphotopsia. The technique addresses many of the proposed mechanisms contributing to the development of negative dysphotopsia and can theoretically be used in all patients with chronic symptomatology. In the case we describe, the dysphotopsia resolved immediately after in-the-bag nasal IOL optic truncation.

  15. Apparatus and method for non-contact, acoustic resonance determination of intraocular pressure

    DOEpatents

    Sinha, D.N.; Wray, W.O.

    1994-12-27

    The apparatus and method for measuring intraocular pressure changes in an eye under investigation by detection of vibrational resonances therein. An ultrasonic transducer operating at its resonant frequency is amplitude modulated and swept over a range of audio frequencies in which human eyes will resonate. The output therefrom is focused onto the eye under investigation, and the resonant vibrations of the eye observed using a fiber-optic reflection vibration sensor. Since the resonant frequency of the eye is dependent on the pressure therein, changes in intraocular pressure may readily be determined after a baseline pressure is established. 3 figures.

  16. Comparison of visual outcomes after implantation of diffractive trifocal toric intraocular lens and a diffractive apodized bifocal toric intraocular lens

    PubMed Central

    Gundersen, Kjell Gunnar; Potvin, Rick

    2016-01-01

    Purpose The aim of this study was to compare a new diffractive trifocal toric lens with an apodized diffractive bifocal toric lens in terms of refractive and visual acuity (VA) outcomes, including low-contrast VA (LCVA), as well as the patient’s visual function 3 months after implantation. Patients and methods This is a randomized prospective study involving bilateral implantation of a trifocal toric or a bifocal toric lens. At 3 months postoperatively, the subject’s vision was tested both uncorrected and with his/her best distance correction at: distance (4 m), intermediate (63 cm), and near (40 cm). Binocular defocus curves were measured with no correction and with the subject’s best distance correction in place. Quality of vision was measured using the National Eye Institute Visual Function Questionnaire. Results A total of 22 patients were enrolled (eleven in each group). There was no statistically significant difference in the absolute change in measured rotation between 1 month and 3 months postoperatively between the two intraocular lens (IOL) groups (P=0.98). At 3 months, the postoperative refraction and distance VA by eye were similar between groups. There was no statistically significant difference in the measured LCVA between groups (P=0.39). The defocus curve showed that at 67 cm, the trifocal toric lens had statistically significantly better VA when compared to the bifocal toric lens. There were no statistically significant differences by group for any of the National Eye Institute Visual Function Questionnaire scores (P>0.26 in all cases). Conclusion The trifocal toric IOL improved the intermediate vision without negatively impacting visual function and distance, near, or low-contrast VA when compared to a bifocal toric IOL. The toric component of the trifocal lens effectively reduced astigmatism and provided good rotational stability. PMID:27051269

  17. Clinical Outcomes after Uncomplicated Cataract Surgery with Implantation of the Tecnis Toric Intraocular Lens

    PubMed Central

    Lubiński, Wojciech; Kaźmierczak, Beata; Gronkowska-Serafin, Jolanta; Podborączyńska-Jodko, Karolina

    2016-01-01

    Purpose. To evaluate the clinical outcomes after uncomplicated cataract surgery with implantation of an aspheric toric intraocular lens (IOL) during a 6-month follow-up. Methods. Prospective study including 27 consecutive eyes of 18 patients (mean age: 66.1 ± 11.4 years) with a visually significant cataract and corneal astigmatism ≥ 0.75 D and undergoing uncomplicated cataract surgery with implantation of the Tecnis ZCT toric IOL (Abbott Medical Optics). Visual, refractive, and keratometric outcomes as well as IOL rotation were evaluated during a 6-month follow-up. At the end of the follow-up, patient satisfaction and perception of optical/visual disturbances were also evaluated using a subjective questionnaire. Results. At 6 months after surgery, mean LogMAR uncorrected (UDVA) and corrected distance visual acuity (CDVA) were 0.19 ± 0.12 and 0.14 ± 0.10, respectively. Postoperative UDVA of 20/40 or better was achieved in 92.6% of eyes. Mean refractive cylinder decreased significantly from −3.73 ± 1.96 to −1.42 ± 0.88 D (p < 0.001), while keratometric cylinder did not change significantly (p = 0.44). Mean absolute IOL rotation was 1.1 ± 2.4°, with values of more than 5° in only 2 eyes (6.9%). Mean patient satisfaction score was 9.70 ± 0.46, using a scale from 0 (not at all satisfied) to 10 (very satisfied). No postoperative optical/visual disturbances were reported. Conclusion. Cataract surgery with implantation of the Tecnis toric IOL is an effective method of refractive correction in eyes with corneal astigmatism due to the good IOL positional stability, providing high levels of patient's satisfaction. PMID:27022478

  18. Muscular and intraocular pressure responses among ocular-hypertensive subjects: is there a rationale for biofeedback?

    PubMed

    Raczynski, J M; Mason, D A; Wilson, R P; Silvia, E S; Kleinstein, R N

    1985-12-01

    Several animal and human investigations have indicated that intraocular pressure (IOP) levels may be associated with extreme drug-induced changes in the extraocular muscles. Further, recent data suggest that, among individuals with normal IOP level, moderate increases in facial muscle (EMG) activity around the eye while the eye is open are associated with increases in IOP. To investigate further the relationship between facial EMG activity and IOP levels and to examine a group of individuals with elevated IOP levels, subjects were recruited from outpatients at an optometry clinic. Three groups of subjects were selected: a group of ocular hypertensive subjects who showed elevated pressures at the optometry clinic and upon the day of testing, a group of labile ocular hypertensive subjects who evinced elevated pressures during their visit to the optometry clinic but lower pressures on the day of testing, and a group of normal IOP subjects who showed normal pressures both during their optometry clinic visit and on the day of testing. To investigate anxiety differences, subjects were administered the State-Trait Anxiety Inventory, but subsequent analysis revealed no group differences. To evaluate the role of stress upon muscle (EMG) functioning around the eye, subjects were subjected to imagery and standardized mental arithmetic stressors; analyses of these results also revealed no significant group differences. Finally, subjects were given EMG biofeedback for muscle activity around the eye while IOP was assessed during five alternating periods in which they made decreases and increases in EMG activity. Results revealed significant group, period, and group by period interaction effects. The pattern of results is interpreted as implicating EMG activity in IOP fluctuations; the implications of these data for potential biofeedback and stress management treatments are discussed.

  19. Visual outcomes and optical quality after implantation of a diffractive multifocal toric intraocular lens

    PubMed Central

    Chen, Xiangfei; Zhao, Ming; Shi, Yuhua; Yang, Liping; Lu, Yan; Huang, Zhenping

    2016-01-01

    Background: This study evaluated the visual function after implantation of a multifocal toric intraocular lenses (IOLs). Materials and Methods: This study involved 10 eyes from eight cataract patients with corneal astigmatism of 1.0 diopter (D) or higher who had received phacoemulsification with implantation of an AcrySof IQ ReSTOR Toric IOL. Six-month evaluations included visual acuity, spherical equivalent (SE), defocus curve, residual astigmatism, IOL rotation, contrast sensitivity (CS), wavefront aberrations, modulation transfer function (MTF), and patient satisfaction assessments. Results: At 6 months postoperatively, uncorrected distance visual acuity (logarithm of the minimum angle of resolution) was 0.09 ± 0.04, corrected distance visual acuity was 0.02 ± 0.11, and uncorrected near visual acuity was 0.12 ± 0.07. The mean SE was −0.095 ± 0.394 D (±0.50 D in 90%). Refractive astigmatism at the 6-month follow-up visit was significantly reduced to 0.35 ± 0.32 D from 1.50 ± 0.41 D presurgery (P < 0.05). The mean IOL axis rotation was 3.20 ± 1.55°. Postoperative CS levels were high. Postoperative total order aberrations (TOAs), lower-order aberrations (LOAs), higher-order aberrations (HOAs), and spherical aberrations were decreased compared with preoperative values (P < 0.05). At 3 months postoperatively, TOAs, LOAs, and HOAs with a 3 mm pupil diameter as well as TOAs, LOAs, and astigmatism aberrations with a 5 mm pupil diameter were statistically lower than those at 1-month post surgery, but without subsequent significant changes (P > 0.05). There was an increase in MTF results between preoperative and postoperative evaluations at all spatial frequencies. Conclusions: The diffractive multifocal toric IOL is able to provide a predictable astigmatic correction with apparently outstanding levels of optical quality after implantation. PMID:27221680

  20. Clinical factors affecting intraocular pressure change after orbital decompression surgery in thyroid-associated ophthalmopathy

    PubMed Central

    Jeong, Jae Hoon; Lee, Jeong Kyu; Lee, Dong Ik; Chun, Yeoun Sook; Cho, Bo Youn

    2016-01-01

    Objective To report the physiological monitoring of intraocular pressure (IOP) during the postoperative periods after orbital decompression surgery and ascertain the correlation between the clinical factors and IOP changes. Methods The medical records of 113 orbits from 60 patients who underwent orbital decompression surgery were reviewed retrospectively. IOP measurement during the postoperative periods was classified based on the postoperative day: week 1 (1–7 days), month 1 (8–41 days), month 2 (42–70 days), month 3 (71–97 days), month 4 (98–126 days), and final (after 127 days). The mean postoperative follow-up was 286.5 days for orbits with at least 6 months of follow-up. Univariate and multivariate linear regression analyses were performed to assess the correlation between the IOP reduction percentage and clinical factors. Results The mean IOP increased from 16.9 to 18.6 mmHg (10.1%) at postoperative week 1 and decreased to 14.4 mmHg (14.5%) after 2 months. Minimal little changes were observed postoperatively in the IOP after 2 months. Preoperative IOP had a significant positive effect on the reduction percentage both at postoperative week 1 (β=2.51, P=0.001) and after 2 months (β=1.07, P=0.029), and the spherical equivalent showed a positive correlation with the reduction level at postoperative week 1 (β=1.71, P=0.021). Conclusion Surgical decompression caused a significant reduction in the IOP in thyroid-associated orbitopathy, and the amount of reduction was closely related to preoperative IOP; however, it may also cause a transient elevation in the IOP during the early postoperative phase in highly myopic eyes. PMID:26848257

  1. The effect of orbital decompression surgery on refraction and intraocular pressure in patients with thyroid orbitopathy

    PubMed Central

    Norris, J H; Ross, J J; Kazim, M; Selva, D; Malhotra, R

    2012-01-01

    Purpose To investigate the effect of orbital decompression surgery in thyroid orbitopathy (TO) on both refractive status and intraocular pressure (IOP). Patients and methods A prospective, multicentre, consecutive audit of patients undergoing thyroid decompression surgery. Indications for surgery included cosmetically unacceptable proptosis or corneal exposure. Exclusion criteria included the following: previous orbital surgery, glaucoma, corneal disease, steroid use in the preceding 12 months, or an acute optic neuropathy. Automated refraction, keratometry, pachymetry, Hertel exophthalmometry, and IOP were recorded at 1 month pre- and 3 months postoperatively. IOP using the Tono-Pen (mean of three readings) was measured in the primary, upgaze, and downgaze positions. Results Data were collected from 52 orbits of 33 patients (East Grinstead, New York, and Adelaide). There was no significant difference between pre- and postoperative data for sphere, cylinder, or central corneal thickness (CCT). The mean spherical equivalent was −0.43±1.49 D pre-operatively and −0.28±1.52 D postoperatively. The steepest meridian of corneal curvature was 93.1 degrees pre- and 94.2 degrees postoperatively, with no significant difference. Mean IOP significantly decreased when measuring by Goldmann applanation tonometry (GAT) (2.28 mm Hg, * P=0.001) and Tono-Pen (3.06 mm Hg, * P=<0.0001). IOP measured in upgaze was significantly greater than that in the primary position. Regression analysis between change in IOP and either Hertel exophthalmometry or the number of orbital walls decompressed was non-significant (*Student's t-test). Conclusion Patients with TO undergoing orbital decompression had, on average, with-the-rule astigmatism not affected by orbital decompression surgery. IOP was significantly reduced by decompression surgery although no relationship between IOP and the degree of decompression was observed. PMID:22261739

  2. The relation between intraocular pressure change and plasma natriuretic peptide under simulated hypobaric conditions

    PubMed Central

    Karadag, Remzi; Sen, Ahmet; Yildirim, Nilgun; Basmak, Hikmet; Golemez, Haydar; Cakir, Erdinc; Akin, Ahmet

    2010-01-01

    Purpose: To ascertain whether the changes in intraocular pressure (IOP) that occur during hypobaric hypoxic exposure are related to plasma N-terminal pro-brain natriuretic peptide (BNP) levels. Materials and Methods: The study group comprised 26 healthy participants (all male, mean age 23.1 years). IOP was measured at local ground level, (792 m above sea level), then while in a chamber providing hypobaric hypoxic conditions (the subjects were exposed to a pressure equivalent to 9144 m for 1-3 min), and again after exit from the chamber. In each condition, the mean of three consecutive measurements of IOP was calculated for each eye. For BNP measurements, blood samples were drawn before the participants entered the chamber and just after they left the chamber. Results: IOP during hypobaric hypoxic exposure (18.00 ± 3.70 mmHg) was significantly greater than that before (15.66 ± 2.10 mmHg, P < 0.001) or after (16.10 ± 2.63 mmHg, P = 0.001) the exposure. IOP levels before and after the exposure were not significantly different (P = 0.136). Plasma BNP levels measured before and after exposure to hypobaric hypoxic conditions were not significantly different (P = 0.462). Conclusion: Plasma BNP levels did not change after short-term hypobaric hypoxic exposure, while the IOP increased. This increase may have been caused by some other systemic factors. As the hypobaric hypoxic conditions were reversed, IOP decreased to normal levels. PMID:20413920

  3. 28-day intraocular pressure reduction with a single dose of brimonidine tartrate-loaded microspheres.

    PubMed

    Fedorchak, Morgan V; Conner, Ian P; Medina, Carlos A; Wingard, Jeremy B; Schuman, Joel S; Little, Steven R

    2014-08-01

    Treatment of glaucoma by intraocular pressure (IOP) reduction is typically accomplished through the administration of eye drops, the difficult and frequent nature of which contributes to extremely low adherence rates. Poor adherence to topical treatment regimens in glaucoma patients can lead to irreversible vision loss and increased treatment costs. Currently there are no approved treatments for glaucoma that address the inherent inefficiencies in drug delivery and patient adherence. Brimonidine tartrate (BT), a common glaucoma medication, requires dosing every 8-12 h, with up to 97% of patients not taking it as prescribed. This study provides proof-of-principle testing of a controlled release BT formulation. BT was encapsulated in poly(lactic-co-glycolic) acid microspheres and drug release was quantified using UV-Vis spectroscopy. For in vivo studies, rabbits were randomized to receive a single subconjunctival injection of blank (no drug) or BT-loaded microspheres or twice daily topical 0.2% BT drops. The microspheres released an average of 2.1 ± 0.37 μg BT/mg microspheres/day in vitro. In vivo, the percent decrease in IOP from baseline was significantly greater in the treated eye for both topical drug and drug-loaded microspheres versus blank microspheres throughout the 4-week study, with no evidence of migration or foreign body response. IOP measurements in the contralateral, untreated eyes also suggested a highly localized effect from the experimental treatment. A treatment designed using the release systems described in this study would represent a vast improvement over the current clinical standard of 56-84 topical doses over 28 days.

  4. Dorsomedial/Perifornical Hypothalamic Stimulation Increases Intraocular Pressure, Intracranial Pressure, and the Translaminar Pressure Gradient

    PubMed Central

    Samuels, Brian C.; Hammes, Nathan M.; Johnson, Philip L.; Shekhar, Anantha; McKinnon, Stuart J.; Allingham, R. Rand

    2012-01-01

    Purpose. Intraocular pressure (IOP) fluctuation has recently been identified as a risk factor for glaucoma progression. Further, decreases in intracranial pressure (ICP), with postulated increases in the translaminar pressure gradient across the lamina cribrosa, has been reported in glaucoma patients. We hypothesized that circadian fluctuations in IOP and the translaminar pressure gradient are influenced, at least in part, by central autonomic regulatory neurons within the dorsomedial and perifornical hypothalamus (DMH/PeF). This study examined whether site-directed chemical stimulation of DMH/PeF neurons evoked changes in IOP, ICP, and the translaminar pressure gradient. Methods. The GABAA receptor antagonist bicuculline methiodide (BMI) was stereotaxically microinjected into the DMH/PeF region of isoflurane-anesthetized male Sprague-Dawley rats (n = 19). The resulting peripheral cardiovascular (heart rate [HR] and mean arterial pressure [MAP]), IOP, and ICP effects were recorded and alterations in the translaminar pressure gradient calculated. Results. Chemical stimulation of DMH/PeF neurons evoked significant increases in HR (+69.3 ± 8.5 beats per minute); MAP (+22.9 ± 1.6 mm Hg); IOP (+7.1 ± 1.9 mm Hg); and ICP (+3.6 ± 0.7 mm Hg) compared with baseline values. However, the peak IOP increase was significantly delayed compared with ICP (28 vs. 4 minutes postinjection), resulting in a dramatic translaminar pressure gradient fluctuation. Conclusions. Chemical stimulation of DMH/PeF neurons evokes substantial increases in IOP, ICP, and the translaminar pressure gradient in the rat model. Given that the DMH/PeF neurons may be a key effector pathway for circadian regulation of autonomic tone by the suprachiasmatic nucleus, these findings will help elucidate novel mechanisms modulating circadian fluctuations in IOP and the translaminar pressure gradient. PMID:23033392

  5. Sustained Antibiotic-Eluting Intra-Ocular Lenses: A New Approach

    PubMed Central

    Tan, Dulcia W. N.; Lim, Soo Ghim; Wong, Tina T.; Venkatraman, Subbu S.

    2016-01-01

    Currently, infections following cataract surgery are not as effectively managed with antibiotic eye drops, which suffer from poor bioavailability of drug and low patient compliance. The ideal solution, which can help to overcome the issue of drug wastage and poor bioavailabilty, as well as the need for frequent applications (patient inconvenience), is a drug-eluting intraocular lens (IOL). We describe a novel approach to such a drug-eluting lens by using a peripheral IOL attachment as a drug depot to deliver antibiotics, Levofloxacin (LFX) or Moxifloxacin (MFX). In this work, drug was entrapped within a fully-degradable polymer, poly(L-lactide-co-ɛ-caprolactone) (PLC). The effects of drug loading and solvent type on drug release and film morphology were investigated using cast films. The study clearly demonstrated that a slower-evaporating solvent tetrahydrofuran (THF) resulted in a better surface morphology, as well as lower initial burst compared to dichloromethane (DCM), and hence, was better suited to developing a drug-eluting attachment with sustained release of drug. When attachments were fabricated with drugs at high loading percentages (20% and 25% in polymer), significant burst was observed compared to films: this is attributed to the higher surface-to-volume ratio of the attachments. When the levofloxacin (LFX) loading percentage was decreased to 3% and 5%, the attachments presented lower burst and sustained release with therapeutic efficacy. This work has demonstrated the potential of using an IOL attachment as a more efficacious anti-infective option compared to daily eye drops. PMID:27741256

  6. Collaborative virtual environments art exhibition

    NASA Astrophysics Data System (ADS)

    Dolinsky, Margaret; Anstey, Josephine; Pape, Dave E.; Aguilera, Julieta C.; Kostis, Helen-Nicole; Tsoupikova, Daria

    2005-03-01

    This panel presentation will exhibit artwork developed in CAVEs and discuss how art methodologies enhance the science of VR through collaboration, interaction and aesthetics. Artists and scientists work alongside one another to expand scientific research and artistic expression and are motivated by exhibiting collaborative virtual environments. Looking towards the arts, such as painting and sculpture, computer graphics captures a visual tradition. Virtual reality expands this tradition to not only what we face, but to what surrounds us and even what responds to our body and its gestures. Art making that once was isolated to the static frame and an optimal point of view is now out and about, in fully immersive mode within CAVEs. Art knowledge is a guide to how the aesthetics of 2D and 3D worlds affect, transform, and influence the social, intellectual and physical condition of the human body through attention to psychology, spiritual thinking, education, and cognition. The psychological interacts with the physical in the virtual in such a way that each facilitates, enhances and extends the other, culminating in a "go together" world. Attention to sharing art experience across high-speed networks introduces a dimension of liveliness and aliveness when we "become virtual" in real time with others.

  7. Stratospheric ozone is decreasing

    NASA Astrophysics Data System (ADS)

    Kerr, Richard A.

    1988-03-01

    The recent discovery that chlorofluorocarbons create the Antarctic ozone hole every October through reactions mediated by ice particles formed at the lowest temperatures of the stratosphere is discussed. A large-scale reanalysis of measurements reveals that protective stratospheric ozone has decreased during the past 17 yrs with some decreases greatly exceeding predictions. It is noted that standard models did not, and still do not, include the ice in their reaction schemes. A tendency toward larger losses at higher colder latitudes is seen.

  8. Evaluation of pharmacological activities and assessment of intraocular penetration of an ayurvedic polyherbal eye drop (Itone™) in experimental models

    PubMed Central

    2013-01-01

    Background The polyherbal eye drop (Itone™) is a mixture of aqueous distillates of nineteen traditionally used ingredients that sum up to impart potency to the formulation and make it a useful adjunct in various ocular pathologies. However, as there have been no controlled experimental studies accounting to the above claim, therefore, the present study was designed to evaluate the polyherbal formulation (PHF) for antiangiogenic, anti-inflammatory, anticataract, antioxidant and cytotoxicity in addition to the evaluation of intraocular penetration of PHF in rabbit eyes using LC-MS/MS. Materials and methods Antiangiogenic activity of the PHF was evaluated using in ovo chick chorio-allantoic membrane (CAM) assay and in vivo cautery induced corneal neovascularization assay in rats. Anticataract potential was evaluated using steroid induced cataract in developing chick embryos, sodium selenite induced cataract in rat pups and galactose induced cataract in rats. The antioxidant activity was evaluated using di-phenyl picryl hydrazyl (DPPH) radical scavenging assay. Anti-inflammatory activity was evaluated in vitro using inhibition of LTB4 formation in human WBCs and in vivo using carrageenan induced paw edema assay in rats. The cytotoxicity was evaluated against HeLa cancer cell lines using (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Furthermore evaluation of the intraocular penetration of the PHF was carried out in rabbit eyes via aqueous humor paracentesis and further analysis using LC-MS/MS. Results PHF significantly inhibited VEGF induced proliferation of new blood vessels in CAM assay and inhibited the cautery induced corneal neovascularization in rats. Additionally, PHF showed noticeable delay in the progression of cataract in the selenite and galactose induced cataract models whereby the PHF treated lenses were graded for stages II and III respectively. However, the PHF did not show any anticataract activity in the hydrocortisone

  9. Phakic Intraocular Lenses for the Treatment of Refractive Errors

    PubMed Central

    2009-01-01

    Executive Summary Objective The objective of this analysis is to review the effectiveness, safety, and cost-effectiveness of phakic intraocular lenses (pIOLs) for the treatment of myopia, hyperopia, and astigmatism. Clinical Need: Condition and Target Population Refractive Errors Refractive errors occur when the eye cannot focus light properly. In myopia (near- or short-sightedness), distant objects appear blurry because the axis of the eye is too long or the cornea is too steep, so light becomes focused in front of the retina. Hyperopia (far sightedness) occurs when light is focused behind the retina causing nearby objects to appear blurry. In astigmatism, blurred or distorted vision occurs when light is focused at two points rather than one due to an irregularly shaped cornea or lens. Refractive errors are common worldwide, but high refractive errors are less common. In the United States, the prevalence of high myopia (≤ −5 D) in people aged 20 to 39, 40 to 59, and 60 years and older is 7.4% (95% confidence interval [CI], 6.5% – 8.3%), 7.8% (95% CI, 6.4% – 8.6%), and 3.1% (95% CI, 2.2% – 3.9%), respectively. The prevalence of high hyperopia (≥ 3 D) is 1.0% (95% CI, .6% – 1.4%), 2.4% (95% CI, 1.7% – 3.0%), and 10.0% (95% CI, 9.1% – 10.9%) for the same age groupings. Finally, the prevalence of astigmatism (≥ 1 D cylinder) is 23.1% (95% CI, 21.6% – 24.5%), 27.6% (95% CI, 25.8% – 29.3%) and 50.1% (48.2% – 52.0%). Low Vision According to the Ontario Schedule of Benefits, low visual acuity is defined by a best spectacle corrected visual acuity (BSCVA) of 20/50 (6/15) or less in the better eye and not amenable to further medical and/or surgical treatment. Similarly, the Ontario Assistive Devices Program defines low vision as BSCVA in the better eye in the range of 20/70 or less that cannot be corrected medically, surgically, or with ordinary eyeglasses or contact lenses. Estimates of the prevalence of low vision vary. Using the criteria of

  10. Systemic Medication and Intraocular Pressure in a British Population

    PubMed Central

    Khawaja, Anthony P.; Chan, Michelle P.Y.; Broadway, David C.; Garway-Heath, David F.; Luben, Robert; Yip, Jennifer L.Y.; Hayat, Shabina; Wareham, Nicholas J.; Khaw, Kay-Tee; Foster, Paul J.

    2014-01-01

    Objective To determine the association between systemic medication use and intraocular pressure (IOP) in a population of older British men and women. Design Population-based, cross-sectional study. Participants We included 7093 participants from the European Prospective Investigation into Cancer–Norfolk Eye Study. Exclusion criteria were a history of glaucoma therapy (medical, laser, or surgical), IOP asymmetry between eyes of >5 mmHg, and missing data for any covariables. The mean age of participants was 68 years (range, 48–92) and 56% were women. Methods We measured IOP using the Ocular Response Analyzer. Three readings were taken per eye and the best signal value of the Goldmann-correlated IOP value considered. Participants were asked to bring all their medications and related documentation to the health examination, and these were recorded by the research nurse using an electronic case record form. The medication classes examined were angiotensin-converting enzyme inhibitors, angiotensin-receptor blockers, α-blockers, β-blockers, calcium channel blockers, diuretics, nitrates, statins, insulin, biguanides, sulfonylureas, aspirin, and other nonsteroidal anti-inflammatory drugs. We examined associations between medication use and IOP using multivariable linear regression models adjusted for age, sex, and body mass index. Models containing diabetic medication were further adjusted for glycosylated hemoglobin levels. Main Outcome Measures Mean IOP of the right and left eyes. Results Use of systemic β-blockers (−0.92 mmHg; 95% CI, −1.19, −0.65; P<0.001) and nitrates (−0.63 mmHg; 95% CI, −1.12, −0.14; P = 0.011) were independently associated with lower IOP. The observed associations between statin or aspirin use with IOP were no longer significant after adjustment for β-blocker use. Conclusions This is the first population-based study to demonstrate and quantify clinically significant differences in IOP among participants using systemic

  11. Drug loading of foldable commercial intraocular lenses using supercritical impregnation.

    PubMed

    Bouledjouidja, A; Masmoudi, Y; Sergent, M; Trivedi, V; Meniai, A; Badens, E

    2016-03-16

    The drug delivery through intraocular lenses (IOLs) allows the combination of cataract surgery act and postoperative treatment in a single procedure. In order to prepare such systems, "clean" supercritical CO2 processes are studied for loading commercial IOLs with ophthalmic drugs. Ciprofloxacin (CIP, an antibiotic) and dexamethasone 21-phosphate disodium (DXP, an anti-inflammatory drug) were impregnated into foldable IOLs made from poly-2-hydroxyethyl methacrylate (P-HEMA). A first pre-treatment step was conducted in order to remove absorbed conditioning physiological solution. Supercritical impregnations were then performed by varying the experimental conditions. In order to obtain transparent IOLs and avoid the appearance of undesirable foaming, it was necessary to couple slow pressurization and depressurization phases during supercritical treatments. The impregnation yields were determined through drug release studies. For both drugs, release studies show deep and reproducible impregnation for different diopters. For the system P-HEMA/CIP, a series of impregnations was performed to delimit the experimental range at two pressures (80 and 200 bar) in the presence or absence of ethanol as a co-solvent for two diopters (+5.0 D and +21.0 D). Increase in pressure in the absence of a co-solvent resulted in improved CIP impregnation. The addition of ethanol (5 mol%) produced impregnation yields comparable to those obtained at 200 bar without co-solvent. A response surface methodology based on experimental designs was used to study the influence of operating conditions on impregnation of IOLs (+21.0 D) in the absence of co-solvent. Two input variables with 5 levels each were considered; the pressure (80-200 bar) and the impregnation duration (30-240 min). CIP impregnation yields ranging between 0.92 and 3.83 μg CIP/mg IOL were obtained from these experiments and response surface indicated the pressure as a key factor in the process. The DXP impregnation in P-HEMA was

  12. Decreasing strabismus surgery

    PubMed Central

    Arora, A; Williams, B; Arora, A K; McNamara, R; Yates, J; Fielder, A

    2005-01-01

    Aim: To determine whether there has been a consistent change across countries and healthcare systems in the frequency of strabismus surgery in children over the past decade. Methods: Retrospective analysis of data on all strabismus surgery performed in NHS hospitals in England and Wales, on children aged 0–16 years between 1989 and 2000, and between 1994 and 2000 in Ontario (Canada) hospitals. These were compared with published data for Scotland, 1989–2000. Results: Between 1989 and 1999–2000 the number of strabismus procedures performed on children, 0–16 years, in England decreased by 41.2% from 15 083 to 8869. Combined medial rectus recession with lateral rectus resection decreased from 5538 to 3013 (45.6%) in the same period. Bimedial recessions increased from 489 to 762, oblique tenotomies from 43 to 121, and the use of adjustable sutures from 29 to 44, in 2000. In Ontario, operations for squint decreased from 2280 to 1685 (26.1%) among 0–16 year olds between 1994 and 2000. Conclusion: The clinical impression of decrease in the frequency of paediatric strabismus surgery is confirmed. In the authors’ opinion this cannot be fully explained by a decrease in births or by the method of healthcare funding. Two factors that might have contributed are better conservative strabismus management and increased subspecialisation that has improved the quality of surgery and the need for re-operation. This finding has a significant impact upon surgical services and also on the training of ophthalmologists. PMID:15774914

  13. Spontaneous intraocular lens extrusion in a patient with scleromalacia secondary to herpes zoster ophthalmicus.

    PubMed

    Ahmed, Taha Y; Carrim, Zia I; Diaper, Charles J M; Wykes, William N

    2007-05-01

    We report a case of spontaneous intraocular lens (IOL) extrusion in association with scleromalacia 10 years after uneventful endocapsular surgery. The patient had a history of iridocyclitis secondary to herpes zoster ophthalmicus in the affected eye. A minimally invasive approach involving repositioning the IOL and closure with a conjunctival flap resulted in restoration of visual acuity.

  14. Persistent Intraocular Rubella Infection in a Patient with Fuchs' Uveitis and Congenital Rubella Syndrome

    PubMed Central

    Varga, Zsolt; Parmar, Dipak; Brown, Kevin E.

    2013-01-01

    There is growing evidence for the role of rubella virus in Fuchs' uveitis syndrome (FUS). This report is the first to show persistent intraocular rubella virus in a 28-year-old man with congenital rubella syndrome (CRS), who presented with blurred vision and was diagnosed with FUS. PMID:23426927

  15. Evaluation of Different Power of Near Addition in Two Different Multifocal Intraocular Lenses

    PubMed Central

    Unsal, Ugur; Baser, Gonen

    2016-01-01

    Purpose. To compare near, intermediate, and distance vision and quality of vision, when refractive rotational multifocal intraocular lenses with 3.0 diopters or diffractive multifocal intraocular lenses with 2.5 diopters near addition are implanted. Methods. 41 eyes of 41 patients in whom rotational +3.0 diopters near addition IOLs were implanted and 30 eyes of 30 patients in whom diffractive +2.5 diopters near addition IOLs were implanted after cataract surgery were reviewed. Uncorrected and corrected distance visual acuity, intermediate visual acuity, near visual acuity, and patient satisfaction were evaluated 6 months later. Results. The corrected and uncorrected distance visual acuity were the same between both groups (p = 0.50 and p = 0.509, resp.). The uncorrected intermediate and corrected intermediate and near vision acuities were better in the +2.5 near vision added intraocular lens implanted group (p = 0.049, p = 0.005, and p = 0.001, resp.) and the uncorrected near vision acuity was better in the +3.0 near vision added intraocular lens implanted group (p = 0.001). The patient satisfactions of both groups were similar. Conclusion. The +2.5 diopters near addition could be a better choice in younger patients with more distance and intermediate visual requirements (driving, outdoor activities), whereas the + 3.0 diopters should be considered for patients with more near vision correction (reading). PMID:27340560

  16. Laser ablation and high precision patterning of biomaterials and intraocular lenses

    NASA Astrophysics Data System (ADS)

    Serafetinides, A. A.; Spyratou, E.; Makropoulou, M.

    2010-10-01

    The use of intraocular lenses (IOL) is the most promising method for restoring excellent vision in cataract surgery. In addition, multifocal intraocular lenses for good distant and near vision are investigated. Several new materials, techniques and patterns are studied for the formation and etching of intraocular lenses in order to improve their optical properties and reduce the diffractive aberrations. As pulsed laser ablation is well established as a universal tool for surface processing of organic polymer materials, this study was focused in using laser ablation with short and ultra short laser pulses for surface modification of PMMA and intraocular lenses, instead of using other conventional techniques. The main advantage of using very short laser pulses, e.g. of ns, ps or fs duration, is that heat diffusion into the polymer material is negligible. As a result high precision patterning of the sample, without thermal damage of the surroundings, becomes possible. In this study, laser ablation was performed using commercially available hydrophobic acrylic IOLs, hydrophilic acrylic IOLs, and PMMA IOLs, with various diopters. We investigated the ablation efficiency and the phenomenology of the etched patterns by testing the ablation rate, versus laser energy fluence, at several wavelengths and the surface modification with atomic force microscopy (AFM), or scanning electron microscopy (SEM). The irradiated polymers have different optical properties, at the applied wavelengths, and therefore, present different ablation behaviour and morphology of the laser ablated crater walls and surrounding surfaces. The experimental results, some theoretical assumptions for mathematical modeling of the relevant ablation mechanisms are discussed.

  17. A rapid method for measuring intraocular lens power in vitro with a focimeter.

    PubMed

    García-Domene, Mari Carmen; Díez-Ajenjo, María Amparo; Peris-Martínez, Cristina; Navea, Amparo; Artigas, José María

    2015-11-01

    In this paper we describe a new method for measuring the intraocular lens (IOL) power using a focimeter, a negative ophthalmic lens and a saline solution (0.9% NaCl). To test this we measured the power of 58 different IOLs and we compared them with the power stated by the manufacturer. Despite the limitations, the results show a good correlation.

  18. Scanning electron microscopic study of an anterior chamber intraocular lens: latent endophthalmitis.

    PubMed

    Schémann, J F

    1987-01-01

    Two years after intracapsular cataract extraction and intraocular lens implantation, an anterior chamber lens was removed. The lens was studied by scanning electron microscope which demonstrated the presence of colonies of cocci, a thin acellular membrane covering part of the lens and some modifications of the lens surface.

  19. An Intraocular Camera for Retinal Prostheses: Restoring Sight to the Blind

    NASA Astrophysics Data System (ADS)

    Stiles, Noelle R. B.; McIntosh, Benjamin P.; Nasiatka, Patrick J.; Hauer, Michelle C.; Weiland, James D.; Humayun, Mark S.; Tanguay, Armand R., Jr.

    Implantation of an intraocular retinal prosthesis represents one possible approach to the restoration of sight in those with minimal light perception due to photoreceptor degenerating diseases such as retinitis pigmentosa and age-related macular degeneration. In such an intraocular retinal prosthesis, a microstimulator array attached to the retina is used to electrically stimulate still-viable retinal ganglion cells that transmit retinotopic image information to the visual cortex by means of the optic nerve, thereby creating an image percept. We describe herein an intraocular camera that is designed to be implanted in the crystalline lens sac and connected to the microstimulator array. Replacement of an extraocular (head-mounted) camera with the intraocular camera restores the natural coupling of head and eye motion associated with foveation, thereby enhancing visual acquisition, navigation, and mobility tasks. This research is in no small part inspired by the unique scientific style and research methodologies that many of us have learned from Prof. Richard K. Chang of Yale University, and is included herein as an example of the extent and breadth of his impact and legacy.

  20. Delayed pupillary capture and noninvasive repositioning of a posterior chamber intraocular lens after pupil dilation.

    PubMed

    Galvis, Virgilio; Tello, Alejandro; Montezuma, Sandra

    2002-10-01

    We present a case of pupillary capture of a posterior chamber intraocular lens after routine pupil dilation during a follow-up visit 6 years postoperatively. A noninvasive approach was used to resolve the capture. The possible causes and measures to avoid this complication are discussed.

  1. The effect of blue light exposure and use of intraocular lenses on human uveal melanoma cell lines.

    PubMed

    Marshall, Jean-Claude A; Gordon, Keith D; McCauley, Cristin S; de Souza Filho, João Pessoa; Burnier, Miguel N

    2006-12-01

    Little is known about the effect of blue light on inducing melanocytic malignant transformation. We chose to investigate the effect of blue light (475 nm wavelength) on the proliferation rates of uveal melanoma cells. In addition, we tested two different intraocular lenses to determine the possible effects of ultraviolet absorbing and blue light filtering intraocular lenses on the changes in proliferation. Four human uveal melanoma cell lines (92.1, MKT-BR, OCM-1, SP6.5) were exposed to blue light with and without the presence of ultraviolet absorbing and blue light filtering intraocular lenses. Cells covered by aluminum foil were used as a control. The proliferation rate of the cells compared with the control was then assessed using the Sulforhodamine-B proliferation assay. Cells exposed to blue light showed a statistically significant (P<0.05) increase in proliferation. Those exposed to blue light through a standard ultraviolet absorbing intraocular lens showed a smaller increase in proliferation, whereas those exposed with a blue light filtering intraocular lens showed no increase in proliferation than the control in all four cell lines. The exposure of cells to blue light led to an increase in proliferation in all cell lines compared with the control. The use of blue light filtering intraocular lenses abolished these increases in proliferation in the four cell lines. These results indicate that blue light filtering intraocular lenses may have a protective effect on the proliferation rates of uveal melanoma cells exposed to blue light.

  2. Reference intervals for intraocular pressure measured by rebound tonometry in ten raptor species and factors affecting the intraocular pressure.

    PubMed

    Reuter, Anne; Müller, Kerstin; Arndt, Gisela; Eule, Johanna Corinna

    2011-09-01

    Intraocular pressure (IOP) was measured with the TonoVet rebound tonometer in 10 raptor species, and possible factors affecting IOP were investigated. A complete ophthalmic examination was performed, and IOP was assessed in 2 positions, upright and dorsal recumbency, in 237 birds belonging to the families Accipitridae, Falconidae, Strigidae, and Tytonidae. Mean IOP values of healthy eyes were calculated for each species, and differences between families, species, age, sex, left and right eye, as well as the 2 body positions were evaluated. Physiologic fluctuations of IOP were assessed by measuring IOP serially for 5 days at the same time of day in 15 birds of 3 species. Results showed IOP values varied by family and species, with the following mean IOP values (mm Hg +/- SD) determined: white-tailed sea eagle (Haliaeetus albicilla), 26.9 +/- 5.8; red kite (Milvus milvus), 13.0 +/- 5.5; northern goshawk (Accipiter gentilis), 18.3 +/- 3.8; Eurasian sparrowhawk (Accipiter nisus), 15.5 +/- 2.5; common buzzard (Buteo buteo), 26.9 +/- 7.0; common kestrel (Falco tinnunculus), 9.8 +/- 2.5; peregrine falcon, (Falco peregrinus), 12.7 +/- 5.8; tawny owl (Strix aluco), 9.4 +/- 4.1; long-eared owl (Asio otus), 7.8 +/- 3.2; and barn owl (Tyto alba), 10.8 +/- 3.8. No significant differences were found between sexes or between left and right eyes. In goshawks, common buzzards, and common kestrels, mean IOP was significantly lower in juvenile birds than it was in adult birds. Mean IOP differed significantly by body position in tawny owls (P = .01) and common buzzards (P = .04). By measuring IOP over several days, mean physiologic variations of +/- 2 mm Hg were detected. Differences in IOP between species and age groups should be considered when interpreting tonometric results. Physiologic fluctuations of IOP may occur and should not be misinterpreted. These results show that rebound tonometry is a useful diagnostic tool in measuring IOP in birds of prey because it provides rapid

  3. Etiology and Management of Raised Intraocular Pressure following Posterior Chamber Phakic Intraocular Lens Implantation in Myopic Eyes

    PubMed Central

    Senthil, Sirisha; Choudhari, Nikhil S.; Vaddavalli, Pravin K.; Murthy, Somasheila; Reddy, Jagadesh; Garudadri, Chandra S.

    2016-01-01

    Aim To evaluate the etiology and management of elevated intraocular pressure (IOP) following posterior chamber phakic implantable collamer lens (ICL) surgery. Methods Between 2009 and 2015, 638 eyes of 359 subjects with refractive myopia, underwent V4b and V4c (CentraFLOW) model ICL implantation. Ocular hypertension (OHT) was defined as IOP of ≥ 22 mm Hg on two separate occasions and elevated IOP with corresponding optic disc or visual field damage was defined as glaucoma. Results Elevated IOP ≥ 22 mm Hg was noted in 33 eyes of 30 subjects (33/638; 5.17%). Median age of subjects with raised IOP was 26 years (Inter quartile range (IQR):22, 29) and median refarctive error was -16 diopters (-19.5, -13). The median follow up was 7.8 months (IQR:0.3, 17.6) and median time for postoperative IOP rise was 12 days, (IQR:2, 24). The various etiologies for elevated IOP were steroid response in 21 eyes (64%; 10 eyes with V4b, 11 eyes with V4c), retained viscoelastic in 5 eyes (15%) (3 with V4b, 2 with V4c), pupillary block in four eyes (12%; 3 with V4b, 1 with V4c), malignant glaucoma in one eye (3%, V4b), and missed pre-existing Juvenile open angle glaucoma (JOAG) in two eyes (6% with V4b). Elevated IOP in 31 eyes resolved with conservative management. One eye (centraFLOW design) with central aquaport block by viscoelastic, needed AC wash and one eye with malignant glaucoma needed parsplana vitrectomy and hyaloidotomy. Ten eyes required longterm (>2 months) antiglaucoma medications (AGM) for IOP control. Except the two eyes with JOAG, none had disc and field damage. Conclusion In our series, OHT was seen in 4.85% and glaucoma in 0.3% eyes that underwent V4b and V4c model ICL implantation. Multiple etiologies were noted and steroid induced ocular hypertension was the most common cause of elevated IOP followed by retained viscoelastic and pupillary block. One third of these eyes required longterm AGM for IOP control. PMID:27855172

  4. Robot-assisted intraocular surgery: development of the IRISS and feasibility studies in an animal model

    PubMed Central

    Rahimy, E; Wilson, J; Tsao, T-C; Schwartz, S; Hubschman, J-P

    2013-01-01

    Purpose The aim of this study is to develop a novel robotic surgical platform, the IRISS (Intraocular Robotic Interventional and Surgical System), capable of performing both anterior and posterior segment intraocular surgery, and assess its performance in terms of range of motion, speed of motion, accuracy, and overall capacities. Patients and methods To test the feasibility of performing ‘bimanual' intraocular surgical tasks using the IRISS, we defined four steps out of typical anterior (phacoemulsification) and posterior (pars plana vitrectomy (PPV)) segment surgery. Selected phacoemulsification steps included construction of a continuous curvilinear capsulorhexis and cortex removal in infusion–aspiration (I/A) mode. Vitrectomy steps consisted of performing a core PPV, followed by aspiration of the posterior hyaloid with the vitreous cutter to induce a posterior vitreous detachment (PVD) assisted with triamcinolone, and simulation of the microcannulation of a temporal retinal vein. For each evaluation, the duration and the successful completion of the task with or without complications or involuntary events was assessed. Results Intraocular procedures were successfully performed on 16 porcine eyes. Four eyes underwent creation of a round, curvilinear anterior capsulorhexis without radialization. Four eyes had I/A of lens cortical material completed without posterior capsular tear. Four eyes completed 23-gauge PPV followed by successful PVD induction without any complications. Finally, simulation of microcannulation of a temporal retinal vein was successfully achieved in four eyes without any retinal tears/perforations noted. Conclusion Robotic-assisted intraocular surgery with the IRISS may be technically feasible in humans. Further studies are pending to improve this particular surgical platform. PMID:23722720

  5. Effect of elevated intraocular pressure on the thickness changes of cat laminar and prelaminar tissue using optical coherence tomography.

    PubMed

    Zhao, Qiuyun; Qian, Xiuqing; Li, Lin; Sun, Weijian; Huang, Shan; Liu, Zhicheng

    2014-01-01

    The aim of this study was to examine shape the changes of the lamina cribrosa (LC) under different intraocular pressures (IOPs) with different periods. Images of the optic nerve head were obtained using enhanced depth imaging spectral domain optical coherence tomography (EDI SD-OCT). After an initial scan of the IOP at native pressure, subsequent scanning was taken when the IOP values reached 40, 60, 80 and 100 mm Hg. Then scans continued with the IOP maintained at 100 mm Hg for 1 hour, 2 hours, 3 hours and 4 hours. The thicknesses of the LC and prelaminar tissue were measured and the curvature of the LC was calculated. Our study found that as IOP increased, the thicknesses of both LC and prelaminar tissue decreased and the thickness variation of the LC correlated significantly with the increases of IOP when IOP was higher than 60 mm Hg. An exponential function was proposed to express the relationship between IOP and the thickness variations of LC and prelaminar tissue. Creep curves of the LC and prelaminar tissue was also obtained using the Prony model. In conclusion, both the thickness of the prelaminar tissue and LC thinned as the IOP elevated. The thickness of the LC also decreased after 4 hours of constant 100 mm Hg pressure.

  6. Effects of posterior corneal astigmatism on the accuracy of AcrySof toric intraocular lens astigmatism correction

    PubMed Central

    Zhang, Bin; Ma, Jing-Xue; Liu, Dan-Yan; Guo, Cong-Rong; Du, Ying-Hua; Guo, Xiu-Jin; Cui, Yue-Xian

    2016-01-01

    AIM To evaluate the effects of posterior corneal surface measurements on the accuracy of total estimated corneal astigmatism. METHODS Fifty-seven patients with toric intraocular lens (IOL) implantation and posterior corneal astigmatism exceeding 0.5 diopter were enrolled in this retrospective study. The keratometric astigmatism (KA) and total corneal astigmatism (TA) were measured using a Pentacam rotating Scheimpflug camera to assess the outcomes of AcrySof IOL implantation. Toric IOLs were evaluated in 26 eyes using KA measurements and in 31 eyes using TA measurements. Preoperative corneal astigmatism and postoperative refractive astigmatism were recorded for statistical analysis. The cylindrical power of toric IOLs was estimated in all eyes. RESULTS In all cases, the difference of toric IOL astigmatism magnitude between KA and TA measurements for the estimation of preoperative corneal astigmatism was statistically significant. Of a total of 57 cases, the 50.88% decreased from Tn to Tn-1, and 10.53% decreased from Tn to Tn-2. In all cases, 5.26% increased from Tn to Tn+1. The mean postoperative astigmatism within the TA group was significantly lower than that in the KA group. CONCLUSION The accuracy of total corneal astigmatism calculations and the efficacy of toric IOL correction can be enhanced by measuring both the anterior and posterior corneal surfaces using a Pentacam rotating Scheimpflug camera. PMID:27672591

  7. Calbindins decreased after space flight

    NASA Technical Reports Server (NTRS)

    Sergeev, I. N.; Rhoten, W. B.; Carney, M. D.

    1996-01-01

    Exposure of the body to microgravity during space flight causes a series of well-documented changes in Ca2+ metabolism, yet the cellular and molecular mechanisms leading to these changes are poorly understood. Calbindins, vitamin D-dependent Ca2+ binding proteins, are believed to have a significant role in maintaining cellular Ca2+ homeostasis. In this study, we used biochemical and immunocytochemical approaches to analyze the expression of calbindin-D28k and calbindin-D9k in kidneys, small intestine, and pancreas of rats flown for 9 d aboard the space shuttle. The effects of microgravity on calbindins in rats from space were compared with synchronous Animal Enclosure Module controls, modeled weightlessness animals (tail suspension), and their controls. Exposure to microgravity resulted in a significant and sustained decrease in calbindin-D28k content in the kidney and calbindin-D9k in the small intestine of flight animals, as measured by enzyme-linked immunosorbent assay (ELISA). Modeled weightlessness animals exhibited a similar decrease in calbindins by ELISA. Immunocytochemistry (ICC) in combination with quantitative computer image analysis was used to measure in situ the expression of calbindins in the kidney and the small intestine, and the expression of insulin in pancreas. There was a large decrease of immunoreactivity in renal distal tubular cell-associated calbindin-D28k and in intestinal absorptive cell-associated calbindin-D9k of space flight and modeled weightlessness animals compared with matched controls. No consistent difference in pancreatic insulin immunoreactivity between space flight, modeled weightlessness, and controls was observed. Regression analysis of results obtained by quantitative ICC and ELISA for space flight, modeled weightlessness animals, and their controls demonstrated a significant correlation. These findings after a short-term exposure to microgravity or modeled weightlessness suggest that a decreased expression of calbindins

  8. Circadian Patterns of Intraocular Pressure Fluctuation among Normal-Tension Glaucoma Optic Disc Phenotypes

    PubMed Central

    2016-01-01

    Objective To characterize the 24-h habitual-position intraocular pressure (IOP) patterns of optic disc phenotypes (ODPs) in untreated normal-tension glaucoma (NTG) and the relationships between nocturnal IOP elevation and various clinical factors. Design Prospective, cross-sectional, observational study. Methods Eighty-two NTG patients with focal ischemic (FI) ODP and 82 age- and disease severity-matched NTG patients with myopic glaucomatous (MG) ODP were recruited prospectively over 3 years. The IOP was recorded 11 times over a 24-hour (h) period by a single ophthalmologist using a hand-held tonometer (TonoPen®XL). A cosinor model was used to describe the 24-h IOP rhythm. Associations between nocturnal IOP elevation and both ocular and demographic variables were evaluated using the generalized estimating equation (GEE). Results Mean habitual-position IOP was significantly higher during nighttime than daytime in the FI group (16.44 vs. 14.23 mmHg, P < 0.001), but not in the MG group (15.91 vs. 15.70 mmHg, P = 0.82). The FI group also exhibited a significantly higher peak IOP during sleeping hours (P = 0.01) and lower trough IOP during the 24-h period than the MG group (P < 0.01). The MG group showed a significantly higher peak IOP during waking hours than the FI group (P < 0.01). Therefore, 24-h IOP fluctuation range was significantly higher in the FI group than the MG group (P = 0.013). In the FI group, peak habitual-position IOP and the highest frequency of IOP peaks occurred during sleeping hours (12 AM–6 AM). By contrast, IOP peaks in the MG group occurred during morning hours (8 AM–12 PM). The FI group showed an overall nocturnal acrophase in habitual-position IOP, with 45 patients (54.9%) having a nocturnal acrophase; 10 (12.2%), a diurnal acrophase; and 27 (32.9%), no evident acrophase. By contrast, the MG group showed no evident peak in habitual-position IOP, with 9 patients (10.9%) having a nocturnal acrophase; 43 (52.4%), a diurnal acrophase; and 30

  9. Effect of sildenafil citrate on intraocular pressure and blood pressure in human volunteers.

    PubMed

    Gerometta, Rosana; Alvarez, Lawrence J; Candia, Oscar A

    2011-07-01

    Anecdotal reports have suggested that the vasodilator, sildenafil citrate, which evokes its effect via a select inhibition of PDE5, has the potential to increase intraocular pressure (IOP) in some individuals. An ocular hypertensive effect by sildenafil was also recently described in a sheep animal model. In contrast, clinical studies have not found a direct association between sildenafil ingestion (commonly consumed as Viagra) and changes in IOP. However, some such studies also reported no effects of sildenafil on systemic blood pressure (BP) at the time of the IOP determination. Given this surprising result, our purpose was to repeat a study in human volunteers in the city of Corrientes, Argentina to corroborate the effects of sildenafil on human IOP and systemic BP. For the present study, 9 healthy volunteers (male and female, 18-74 years old) were selected as subjects after ophthalmic and cardiovascular evaluation indicated that they exhibited normal parameters for their age. In a masked, placebo-controlled study, the subjects ingested 100 mg sildenafil citrate (provided as Vorst from Laboratorios Bernabo, Argentina) in one session, and a placebo on a second separate occasion. IOP was measured with a Goldman applanation tonometer by an ophthalmologist, and BP by a second physician, neither of whom witnessed the tablet ingestion by the volunteers, nor provided with information on the nature of the test compounds. A third individual administered the tablets. The average baseline IOP of this group of 9 was 13.1 ± 0.6 mm Hg. Subsequent to sildenafil ingestion, IOP increased by 26% to 16.5 ± 0.8 mm Hg 60 min later (P < 0.005, as paired data), and returned to control values within 2 h. Both systolic and diastolic BP were significantly reduced by sildenafil ingestion. At the point of maximal systemic hypotension (90 min), the systolic and diastolic pressures declined by 15% and 13%, respectively. No significant changes in IOP or BP were recorded after

  10. 2-MeS-β,γ-CCl2-ATP is a Potent Agent for Reducing Intraocular Pressure†

    PubMed Central

    Eliahu, Shay; Martín-Gil, Alba; de Lara, María Jesús Perez; Pintor, Jesús; Camden, Jean; Weisman, Gary A.; Lecka, Joanna; Sévigny, Jean; Fischer, Bilha

    2015-01-01

    Extracellular nucleotides can modify the production or drainage of the aqueous humor via activation of P2 receptors and therefore affect the intraocular pressure (IOP). We have synthesized slowly hydrolyzable nucleoside di- and triphosphate analogues, 1, and 8–14. Analogues 8–14 were completely resistant to hydrolysis by alkaline phosphatase over 30 min at 37 °C. In human blood serum, analogues 8–14 exhibited high stability, e.g., analogues 9 and 10–14 were only 15% and 0% degraded after 24 h, respectively. Moreover, analogues 8–14 were highly stable at pH 1.4 (t1/21 h–30 days). Analogues 8–14 were agonists of the P2Y1 receptor (EC50 0.57–9.54μM). Ocular administration of most analogues into rabbits reduced IOP, e.g., analogue 9 reduced IOP by 32% (EC50 95.5 nM). Analogue 9 was more effective at reducing IOP than several common glaucoma drugs and represents a promising alternative to timolol maleate, which cannot be used for the treatment of patients suffering from asthma or cardiac problems. PMID:20337495

  11. Effects of the new ethacrynic acid oxime derivative SA12590 on intraocular pressure in cats and monkeys.

    PubMed

    Shimazaki, Atsushi; Kirihara, Tomoko; Rao, Ponugoti Vasantha; Tajima, Hisashi; Matsugi, Takeshi; Epstein, David Lee

    2007-08-01

    To evaluate the pharmacological characteristics of SA12590, a new oxime-derivative of the ethacrynic acid (ECA) derivative SA9000, we examined both its ocular hypotensive effects (in ocular normotensive cats and cynomolgus monkeys) and its potential corneal toxicity (in rats). A 50 microl topical administration of 3% SA12590 significantly reduced intraocular pressure (IOP) (by 3.5 mmHg) in anesthetized cats (p<0.05). Twenty-four hours after 3 drops (5-min intervals) of 20 microl 3% SA12590, IOP was reduced by 8 mmHg (p<0.05, n=4) in conscious monkeys without evidence of corneal toxicity. Three days' daily single 20 microl dosing with 3% SA12590 reduced IOP by 4 mmHg (p<0.01, n=3) at 72 h after the first administration in conscious monkeys. The toxicity of topically administered 20 microl 3% SA9000 or SA12590 (3 drops with 5-min intervals) on rat corneal epithelium was assessed using a photo-slit lamp. In this study, 3% SA12590, unlike 3% SA9000, exhibited no corneal toxicity. In a glutathione assay for sulfhydryl (SH) reactivity, SA12590, unlike SA9000, displayed no in vitro SH reactivity. Thus, oxime-modification may both improve efficacy towards IOP upon topical administration and improve the safety profile, probably by enhancing corneal penetration and minimizing SH reactivity-related toxicity. These findings indicate that SA12590 has potential as a new ocular hypotensive drug.

  12. Placement of a collagen glaucoma drainage device to control intraocular pressure and chronic iritis secondary to juvenile rheumatoid arthritis.

    PubMed

    Price, Francis W; Ziemba, Steven L

    2002-01-01

    A patient with juvenile rheumatoid arthritis and chronic iritis is reported with intraocular pressure near 30 mm Hg and previous episodes of intraocular pressure as high as 50 mm Hg despite maximally tolerated medical therapy. Because of the potential risk involved with a full-thickness filtration procedure, it was decided that a nonpenetrating deep sclerectomy would be appropriate, followed by placement of a collagen glaucoma drainage device to maintain aqueous outflow. Immediately postoperatively, intraocular pressure was stabilized. At 24 months postoperatively, intraocular pressure was well controlled at 15 mm Hg with patient receiving only Lotemax. No significant complications were noted at any point in the postoperative course. Because of the patient's predisposition for serious complications frequently associated with trabeculectomy, nonpenetrating deep sclerectomy with the collagen glaucoma drainage device was an effective alternative for this patient.

  13. [The effect of crystalline lens extraction on intraocular pressure in patients with primary open-angle glaucoma].

    PubMed

    Macarie, S; Macarie, Daniela

    2013-01-01

    This issue presents the results of a study on patients with cataract and primary open angle glaucoma who suffered lens extraction for cataract. We analise the effects of the lens extraction on the level of intraocular pressure at this patients.

  14. Exhibits Enhanced by Stand-Alone Computers.

    ERIC Educational Resources Information Center

    Van Rennes, Eve C.

    Both the development and evaluation of one of a set of computer programs designed for use by visitors as adjuncts to museum exhibits are described. Museum displays used were (1) a static, behind-glass exhibit on evolution; (2) a hands-on primitive stone age tools exhibit; and (3) a Foucault pendulum. A computer placed next to each exhibit served…

  15. Combination of Toric and multifocal intraocular lens implantation in bilateral cataract patients with unilateral astigmatism

    PubMed Central

    Liang, Jing-Li; Tian, Fang; Zhang, Hong; Teng, He

    2016-01-01

    AIM To assess the binocular visual function in bilateral cataract patients with unilateral astigmatism after combined implantations of Toric with multifocal intraocular lens (IOL), and to compare with that of Toric and monofocal IOL implantation. METHODS All the 30 patients with unilateral astigmatism suffered bilateral cataract were randomly divided into two groups: Toric plus multifocal IOL group and Toric plus monofocal IOL group. Uncorrected and corrected visual acuity at distance (5.0 m), intermediate distance (0.6 m), and near (0.33 m), contrast sensitivity, and stereopsis were assessed 6mo after surgery. Patients were also surveyed for visual disturbances and spectacle dependence. RESULTS Binocular uncorrected visual acuity (LogMAR) of Toric/multifocal IOL eyes at distance, intermediate, near were 0.05±0.05, 0.24±0.10, and 0.14±0.06 respectively. The values of Toric plus monofocal IOL eyes were 0.06±0.07, 0.26±0.08, and 0.37±0.10 respectively. These values did not indicate significant differences between two groups with exception of near visual acuity. In the photopic condition (with or without glare), the contrast sensitivity of multifocal IOL eyes was significant lower than the monofocal IOL eyes in 18 cpd. In the mesopic condition, the contrast sensitivity of multifocal group was significant lower than monofocal group in 12 cpd, and in mesopic glare condition, this significant difference was found both in 6 cpd and 12 cpd. The stereopsis of Toric/multifocal IOL eyes decreased slightly (100±80 seconds of arc, t=2.222, P=0.136). Mean near vision for patient satisfaction was statistically significantly higher in Toric/multifocal IOL group patients versus than that in Toric/monofocal IOL group (80% vs 25.5%, P=0.000). Visual disturbance was not noticed in either group. CONCLUSION Although the combination of Toric and multifocal IOL implantation results in compromising stereoacuity, it can still provide patients with high levels of spectacle freedom and

  16. Magnifications of Single and Dual Element Accommodative Intraocular Lenses: Paraxial Optics Analysis

    PubMed Central

    Ale, Jit B; Manns, Fabrice; Ho, Arthur

    2010-01-01

    Purpose Using an analytical approach of paraxial optics, we evaluated the magnification of a model eye implanted with single-element (1E) and dual-element (2E) translating-optics accommodative intraocular lenses (AIOL) with an objective of understanding key control parameters relevant to their design. Potential clinical implications of the results arising from pseudophakic accommodation were also considered. Methods Lateral and angular magnifications in a pseudophakic model eye were analyzed using the matrix method of paraxial optics. The effects of key control parameters such as direction (forward or backward) and distance (0 to 2 mm) of translation, power combinations of the 2E-AIOL elements (front element power range +20.0 D to +40.0 D), and amplitudes of accommodation (0 to 4 D) were tested. Relative magnification, defined as the ratio of the retinal image size of the accommodated eye to that of unaccommodated phakic (rLM1) or pseudophakic (rLM2) model eyes, was computed to determine how retinal image size changes with pseudophakic accommodation. Results Both lateral and angular magnifications increased with increased power of the front element in 2E-AIOL and amplitude of accommodation. For a 2E-AIOL with front element power of +35 D, rLM1 and rLM2 increased by 17.0% and 16.3%, respectively, per millimetre of forward translation of the element, compared to the magnification at distance focus (unaccommodated). These changes correspond to a change of 9.4% and 6.5% per dioptre of accommodation, respectively. Angular magnification also increased with pseudophakic accommodation. 1E-AIOLs produced consistently less magnification than 2E-AIOLs. Relative retinal image size decreased at a rate of 0.25% with each dioptre of accommodation in the phakic model eye. The position of the image space nodal point shifted away from the retina (towards the cornea) with both phakic and pseudophakic accommodation. Conclusion Power of the mobile element, and amount and direction of

  17. Design of novel melatonin analogs for the reduction of intraocular pressure in normotensive rabbits.

    PubMed

    Alarma-Estrany, Pilar; Guzman-Aranguez, Ana; Huete, Fernando; Peral, Assumpta; Plourde, Robert; Pelaez, Teresa; Yerxa, Benjamin; Pintor, Jesús

    2011-06-01

    Melatonin, the MT(2) melatonin receptor agonist IIK7 [N-butanoyl-2-(2-methoxy-6H-isoindolo[2,1-a]indol-11-yl)ethanamine], and the putative MT(3) melatonin receptor agonist 5-MCA-NAT [5-methoxycarbonylamino-N-acetyltryptamine] have previously been shown to reduce intraocular pressure (IOP) in ocular normotensive rabbits. To gain a better understanding of the structure-activity relationship of compounds that activate MT(2) and MT(3) receptors mediating reductions in IOP, novel melatonin analogs with rationally varied substitutions were synthesized and tested for their effects on IOP in ocular normotensive rabbits (n = 160). All synthesized melatonin analogs reduced IOP. The best-effect lowering IOP was obtained with the analogs INS48848 [methyl-1-methylene-2,3,4,9-tetrahydro-1H-carbazol-6-ylcarbamate], INS48862 [methyl-2-bromo-3-(2-ethanamidoethyl)-1H-indol-5-ylcarbamate], and INS48852 [(E)-N-(2-(5-methoxy-1H-indol-3-yl)ethyl)-3-phenylprop-2-enamide]. These compounds produced dose-dependent decreases in IOP that were maximal at 0.1 mM (total dose of 0.259 μg for INS48848, 0.354 μg for INS48862, and 0.320 μg for INS48852) and 1 mM (total dose of 2.59 μg for INS48848, 3.54 μg for INS48862, and 3.20 μg for INS48852), with maximal reductions of 36.0 ± 4.0, 24.0 ± 1.5, and 30.0 ± 1.5% for INS48848, INS48862, and INS48852, respectively. Studies using melatonin receptor antagonists (luzindole, prazosin, and DH97 [N-pentanoyl-2-benzyltryptamine]) indicated that INS48862 and INS48852 activate preferentially a MT(2) melatonin receptor and suggest that INS48848 may act mainly via a MT(3) receptor. The most effective compounds were also well tolerated in a battery of standard ocular surface irritation studies. The implication of these findings to the design of novel drugs to treat ocular hypertension is discussed.

  18. Intraocular route of AAV2 vector administration defines humoral immune response and therapeutic potential

    PubMed Central

    Miller, Rehae; Han, Ping-Yang; Pang, Jijing; Dinculescu, Astra; Chiodo, Vince; Hauswirth, William W.

    2008-01-01

    Purpose Safety and efficiency are critical for successful gene therapy. Adeno-associated viral (AAV) vectors are commonly used for gene transfer in both human and animal studies. However, administration of AAV vectors can lead to development of neutralizing antibodies against the vector capsid, thus decreasing the efficiency of therapeutic gene transfer and preventing effective vector readministration. We investigated immune responses to different routes of ocular administration and readministration of AAV vectors, and the effect of previous exposure of AAV vector in one eye on the transduction efficacy of subsequent intraocular AAV-mediated gene delivery to the partner eye. Methods We tested two vector systems. One contained a cDNA encoding a secreted pigment epithelial derived factor (PEDF) cDNA under the control of a Cytomegalovirus (CMV) enhancer and chicken β-actin promoter (CBA; AAV2-CBA-PEDF) and was tested in a murine model of laser-induced choroidal neovascularization (CNV). The other vector contained a cDNA encoding the intracellular reporter green fluorescent protein (GFP) under the control of the same promoter (AAV2-CBA-GFP). Animals were divided into groups and received sequential injections at different combinations of either intravitreal or subretinal routes. CNV was evaluated by fluorescein angiographic choroidal flat-mount image analysis. The expression of GFP was analyzed in retinal sections by direct fluorescence imaging. Antibodies against AAV2 capsid and transgenes were analyzed by ELISA using serum samples collected before injection and different time points after the injection. Neutralizing antibodies were characterized by in vitro assays. Results Various ocular compartments responded to AAV administration differently. Intravitreal administration of AAV vectors, which resulted in transduction of inner retina (primarily retinal ganglion cells), generated a humoral immune response against AAV capsid that blocked vector expression upon

  19. Seasonal changes of 24-hour intraocular pressure rhythm in healthy Shanghai population

    PubMed Central

    Cheng, Jingyi; Xiao, Ming; Xu, Huan; Fang, Shaobin; Chen, Xu; Kong, Xiangmei; Sun, Xinghuai

    2016-01-01

    Abstract The aim of the present study was to investigate and compare the 24-hour intraocular pressure (IOP) rhythms in winter and summer in the healthy population of Shanghai, China. This is a cross-sectional study in which 24-hour IOP measurements were taken for all eligible healthy volunteers in winter and summer, respectively, and the temperature, hours of sunlight (sunlight time), and circulatory parameters, including heart rate, systolic blood pressure, and diastolic blood pressure, were also recorded. The 24-hour IOP curves and IOP parameters (mean, peak, trough, and fluctuation of IOP together with the diurnal-to-nocturnal IOP change) in winter and summer were obtained and compared. The magnitude of IOP changes from summer to winter was also calculated. A total of 29 participants (58 eyes), 14 (48.28%) male and 15 (51.72%) female, aged 43.66 ± 12.20 (19–61) years, were considered eligible for this study. Generally, IOP decreased progressively before noon, increased notably in the nocturnal period, and peaked at 12:00 am in winter and at 2:00 am in summer. The pattern of 24-hour IOP in winter and summer was significantly different (P = 0.002). The average IOPs from 4:00 pm to 8:00 am, except for 6:00 am, were significantly higher in winter (P < 0.05). However, no significant differences were shown after adjusting for temperature and/or sunlight time. From summer to winter, the extent of IOP increase was mostly around 0 to 3 mm Hg, and the IOPs increased more significantly in the nocturnal period than in the diurnal period (P = 0.05). The 24-hour IOP rhythms were different in winter and summer, with higher IOP level in winter. Temperature and sunlight time, which are independent of heart rate and blood pressure, affected the 24-hour IOP rhythms in healthy people in Shanghai, China. Further investigations are expected for the rhythm of some endogenous substance secretion and the inner mechanism of regulation of IOP. PMID:27495076

  20. Associations with intraocular pressure across Europe: The European Eye Epidemiology (E(3)) Consortium.

    PubMed

    Khawaja, Anthony P; Springelkamp, Henriët; Creuzot-Garcher, Catherine; Delcourt, Cécile; Hofman, Albert; Höhn, René; Iglesias, Adriana I; Wolfs, Roger C W; Korobelnik, Jean-François; Silva, Rufino; Topouzis, Fotis; Williams, Katie M; Bron, Alain M; Buitendijk, Gabriëlle H S; Cachulo, Maria da Luz; Cougnard-Grégoire, Audrey; Dartigues, Jean-François; Hammond, Christopher J; Pfeiffer, Norbert; Salonikiou, Angeliki; van Duijn, Cornelia M; Vingerling, Johannes R; Luben, Robert N; Mirshahi, Alireza; Lamparter, Julia; Klaver, Caroline C W; Jansonius, Nomdo M; Foster, Paul J

    2016-11-01

    Raised intraocular pressure (IOP) is the most important risk factor for developing glaucoma, the second commonest cause of blindness globally. Understanding associations with IOP and variations in IOP between countries may teach us about mechanisms underlying glaucoma. We examined cross-sectional associations with IOP in 43,500 European adults from 12 cohort studies belonging to the European Eye Epidemiology (E(3)) consortium. Each study conducted multivariable linear regression with IOP as the outcome variable and results were pooled using random effects meta-analysis. The association of standardized study IOP with latitude was tested using meta-regression. Higher IOP was observed in men (0.18 mmHg; 95 % CI 0.06, 0.31; P = 0.004) and with higher body mass index (0.21 mmHg per 5 kg/m(2); 95 % CI 0.14, 0.28; P < 0.001), shorter height (-0.17 mmHg per 10 cm; 95 % CI -0.25, -0.08; P < 0.001), higher systolic blood pressure (0.17 mmHg per 10 mmHg; 95 % CI 0.12, 0.22; P < 0.001) and more myopic refraction (0.06 mmHg per Dioptre; 95 % CI 0.03, 0.09; P < 0.001). An inverted U-shaped trend was observed between age and IOP, with IOP increasing up to the age of 60 and decreasing in participants older than 70 years. We found no significant association between standardized IOP and study location latitude (P = 0.76). Novel findings of our study include the association of lower IOP in taller people and an inverted-U shaped association of IOP with age. We found no evidence of significant variation in IOP across Europe. Despite the limited range of latitude amongst included studies, this finding is in favour of collaborative pooling of data from studies examining environmental and genetic determinants of IOP in Europeans.

  1. The intraocular pressure-lowering properties of intravenous paracetamol

    PubMed Central

    van den Heever, Henning; Meyer, David

    2016-01-01

    Aim The aim of this paper was to investigate the intraocular pressure (IOP)-changing properties of a single standard dose of intravenous (IV) paracetamol and compare it to that of topical timolol, oral acetazolamide, and no treatment. Methods A prospective, randomized, investigator-blind, parallel-group study was conducted in 73 eyes of 52 subjects. Subjects received a single dose of IV paracetamol (1 g), oral acetazolamide (250 mg), topical timolol (0.5%, one drop), or no treatment. Baseline IOP was measured, and the measurement was repeated at 1, 2, 4, and 6 hours after treatment. Results Paracetamol reduced IOP from baseline by −10.8% (95% confidence interval [CI]: −4.9% to −16.8%, P=0.146) at 1 hour, −13.3% (95% CI: −8.3% to −18.4%, P=0.045) at 2 hours, −11.8% (95% CI: −5.5% to −18.4%, P=1.000) at 4 hours, and −23.9% (95% CI: −17.8% to −30.1%, P=0.006) at 6 hours after treatment. In the no-treatment group, the change was −2.9% (95% CI: +1.0% to −6.7%, P= referent) at 1 hour, −2.1% (95% CI: +2.9% to −7.2%, P= referent) at 2 hours, −7.6% (95% CI: −3.9% to −11.2%, P= referent) at 4 hours, and −6.9% (95% CI: −3.6% to −10.2%, P= referent) at 6 hours. Acetazolamide reduced IOP by −18.8% (95% CI: −12.7% to −24.8%, P=0.000) at 1 hour, −26.2% (95% CI: −18.2% to −34.2%, P=0.001) at 2 hours, −24.6% (95% CI: −16.9% to −32.3%, P=0.000) after 4 hours, and −26.9% (95% CI: −19.6% to −34.3%, P=0.000) 6 hours after treatment. Timolol reduced IOP by −31.2% (95% CI: −26.7% to −35.7%, P=0.000) at 1 hour, −27.7% (95% CI: −20.7% to −34.8%, P=0.000) at 2 hours, −28.7% (95% CI: −21.1% to −36.2%, P=0.000) at 4 hours, and −21.3% (95% CI: −13.4% to −30.0%, P=0.030) at 6 hours after treatment. The average change in IOP for the no-treatment group was −4.8% (95% CI: −2.6% to −6.9%, P= referent). It was −15.7% (95% CI: −9.3% to −22.1%, P=0.021) for paracetamol, −23.1% (95% CI: −16.4% to

  2. Intra-Ocular Pressure Measurement in a Patient with a Thin, Thick or Abnormal Cornea

    PubMed Central

    Clement, Colin I.; Parker, Douglas G.A.; Goldberg, Ivan

    2016-01-01

    Accurate measurement of intra-ocular pressure is a fundamental component of the ocular examination. The most common method of measuring IOP is by Goldmann applanation tonometry, the accuracy of which is influenced by the thickness and biomechanical properties of the cornea. Algorithms devised to correct for corneal thickness to estimate IOP oversimplify the effects of corneal biomechanics. The viscous and elastic properties of the cornea influence IOP measurements in unpredictable ways, a finding borne out in studies of patients with inherently abnormal and surgically altered corneal biomechanics. Dynamic contour tonometry, rebound tonometry and the ocular response analyzer provide useful alternatives to GAT in patients with abnormal corneas, such as those who have undergone laser vision correction or keratoplasty. This article reviews the various methods of intra-ocular pressure measurement available to the clinician and the ways in which their utility is influenced by variations in corneal thickness and biomechanics. PMID:27014386

  3. Cluster headache: interictal asymmetric increment in intraocular pressure elicited by Valsalva manoeuvre.

    PubMed

    Barriga, F J; Sánchez-del-Río, M; Barón, M; Dobato, J l; Gili, P; Yangüela, J; Bueno, A; Pareja, J A

    2004-03-01

    Changes in intraocular pressure (IOP) elicited by a Valsalva manoeuvre were studied in 11 male patients (mean age 39.8 years) suffering from episodic cluster headache (CH), and 12 healthy male controls (mean age 39.9 years). The tests were performed at rest and while exhaling hard through a mouthpiece connected to a mercury manometer. In the CH group, during symptomatic periods, between attacks, Valsalva manoeuvre elicited an asymmetric increase in IOP with significantly higher values on the symptomatic side (P = 0011), whereas no asymmetric increments in IOP were found during asymptomatic periods. Outside the cluster period the IOP values both baseline and with Valsalva manoeuvre did not differ from controls. The increment in IOP took place within a few seconds, as in spontaneous CH attacks, thus pointing to a rapid increase in intraocular blood volume or vasodilatation. These findings may reflect a latent increased vascular reactivity of the symptomatic orbit during CH period.

  4. Implantation of iris-claw Artisan intraocular lens for aphakia in Fuchs’ heterochromic iridocyclitis

    PubMed Central

    Kheirkhah, Ahmad; Nikdel, Mojgan; Ghadimi, Hadi

    2014-01-01

    Implantation of iris-claw Artisan intraocular lens (IOL) is a surgical option for correction of aphakia; however, these IOLs have not been used in eyes with uveitis including Fuchs’ heterochromic iridocyclitis (FHI) due to possible risk of severe postoperative intraocular inflammation. In the case reported here, we secondarily implanted an Artisan IOL in a 28-year-old man with FHI who had aphakia with no capsular support due to a previous complicated cataract surgery. Enclavation was easily performed and no intraoperative complication was noted. Postoperative course was uneventful with no significant anterior chamber inflammation during 12 months of follow-up. Although there were few deposits on the IOL surface, the patient achieved a best-corrected visual acuity of 20/20 without developing glaucoma or other complications. Therefore, Artisan IOL may be considered for correction of aphakia in patients with FHI. However, studies on large number of patients are required to evaluate safety of the procedure. PMID:23571252

  5. An aspheric intraocular telescope for age-related macular degeneration patients.

    PubMed

    Tabernero, Juan; Qureshi, Muhammad A; Robbie, Scott J; Artal, Pablo

    2015-03-01

    We have designed an intraocular telescope for the posterior chamber of the human eye of patients with age related macular degeneration. The basic design is composed of two decentered high optical power lenses ( + 66D and -66D) inducing a 3° prismatic effect to project a magnified central field of view into a healthier location off the central fovea. Aspheric surfaces were used to ensure a compromise between good optical quality and high tolerance to the final axial position of both lenses after surgery. With this particular design, the telescope affords an extended range of depth of focus, high tolerance to different axial lengths of the eye and robustness against typical values of astigmatism and higher order aberrations. The final design has been manufactured in a foldable material and is compact enough to facilitate surgical implantation. This telescope is a simple but promising intraocular visual aid for AMD patients.

  6. Real-Time Retinal Vessel Mapping and Localization for Intraocular Surgery.

    PubMed

    Becker, Brian C; Riviere, Cameron N

    2013-01-01

    Computer-aided intraocular surgery requires precise, real-time knowledge of the vasculature during retinal procedures such as laser photocoagulation or vessel cannulation. Because vitreoretinal surgeons manipulate retinal structures on the back of the eye through ports in the sclera, voluntary and involuntary tool motion rotates the eye in the socket and causes movement to the microscope view of the retina. The dynamic nature of the surgical workspace during intraocular surgery makes mapping, tracking, and localizing vasculature in real time a challenge. We present an approach that both maps and localizes retinal vessels by temporally fusing and registering individual-frame vessel detections. On video of porcine and human retina, we demonstrate real-time performance, rapid convergence, and robustness to variable illumination and tool occlusion.

  7. An aspheric intraocular telescope for age-related macular degeneration patients

    PubMed Central

    Tabernero, Juan; Qureshi, Muhammad A; Robbie, Scott J; Artal, Pablo

    2015-01-01

    We have designed an intraocular telescope for the posterior chamber of the human eye of patients with age related macular degeneration. The basic design is composed of two decentered high optical power lenses ( + 66D and −66D) inducing a 3° prismatic effect to project a magnified central field of view into a healthier location off the central fovea. Aspheric surfaces were used to ensure a compromise between good optical quality and high tolerance to the final axial position of both lenses after surgery. With this particular design, the telescope affords an extended range of depth of focus, high tolerance to different axial lengths of the eye and robustness against typical values of astigmatism and higher order aberrations. The final design has been manufactured in a foldable material and is compact enough to facilitate surgical implantation. This telescope is a simple but promising intraocular visual aid for AMD patients. PMID:25798322

  8. Delivery of Intraocular Triamcinolone Acetonide in the Treatment of Macular Edema

    PubMed Central

    Pickrell, Aaron; Harris, Alon; Ngo, Sandra; Amireskandari, Annahita; Stewart, Erin; Siesky, Brent

    2012-01-01

    Macular edema (ME) is one of the eventual outcomes of various intraocular and systemic pathologies. The pathogenesis for ME is not yet entirely understood; however, some of the common risk factors for its development have been identified. While this investigation will not discuss the numerous etiologies of ME in detail, it appraises the two most widely studied delivery modalities of intraocular corticosteroids in the treatment of ME—intravitreal injection (IVI) and sub-Tenon’s infusion (STI). A thorough review of the medical literature was conducted to identify the efficacy and safety of IVI and STI, specifically for the administration of triamcinolone acetonide (TA), in the setting of ME in an attempt to elucidate a preferred steroid delivery modality for treatment of ME. PMID:24300190

  9. Synthesis, characterization and in vitro studies of celecoxib-loaded poly(ortho ester) nanoparticles targeted for intraocular drug delivery.

    PubMed

    Palamoor, Mallika; Jablonski, Monica M

    2013-12-01

    The present investigation is aimed at improving the ocular bioavailability of a poorly water soluble drug, celecoxib, to offer new options in the treatment of chronic eye diseases, such as age-related macular degeneration and diabetic retinopathy. To do so, we developed a novel formulation of drug-loaded poly(ortho ester) nanoparticles (NPs). We characterized the NPs in terms of size, morphology, controlled-release, degradation and cytocompatibity. Stable and transparent NP emulsions were prepared following a double emulsion solvent diffusion method employing poloxamer 188 as a stabilizer. Physical properties showed a narrow range size distribution of 151-164nm with spherical morphology, negative zeta potentials and remarkably high celecoxib encapsulation efficiency (98%) and loading (64%) of poly(ortho ester) NPs. Drug release followed a zero-order release by a surface erosion-controlled mechanism without any burst effect. Degradation of poly(ortho ester) NPs was observed by measuring the concentration of initial degradation product such as, lactic acid. MTT studies revealed minimal toxicity of NPs (up to 1mg/ml) toward HEK 293 cells. Poly(ortho ester) NPs were not internalized by either Müller or HEK 293 cells, which is highly desirable for a drug carrier to deliver the drugs for prolonged periods to the back of eye. These features have the potential to decrease the number of intraocular injections required to treat chronic eye diseases.

  10. The triple procedure: in the bag placement versus ciliary sulcus placement of the intraocular lens

    PubMed Central

    Borderie, V.; Touzeau, O.; Bourcier, T.; Carvajal-Gonzalez, S.; Laroche, L.

    1999-01-01

    AIMS—To evaluate the influence of intraocular lens (IOL) placement on triple procedure clinical results and to investigate whether it is appropriate to use phacoemulsification in patients with large lens nucleus.
METHODS—40 consecutive penetrating keratoplasties combined with cataract extraction performed in a single institution were studied. Whenever possible a capsulorhexis was performed and the IOL was placed into the capsular bag. Phacoemulsification was used when the nucleus was too large to pass through the capsulorhexis.
RESULTS—Out of 25 patients with an intact capsulorhexis phacoemulsification was used in 13 (52.0%) whereas the entire nucleus passed through the capsulorhexis in the remaining 12 patients (48%). The average 12 month visual acuity was 0.46 (SD 0.21) in patients with in the bag IOL (n = 23) and 0.29 (0.08) in patients with ciliary sulcus IOL (n = 13) (p = 0.04). Elevated intraocular pressure occurred in 26.1% (6/23) of patients with in the bag IOL and 61.5% (8/13) of patients with ciliary sulcus IOL (p = 0.08). The average postoperative graft thickness at 18 months was 552 (27) µm in the former group and 650 (29) µm in the latter group (p = 0.04). No significant difference in graft survival, postoperative endothelial cell density, astigmatism, and videokeratoscopic measurements was found between both groups.
CONCLUSION—In the bag placement of the intraocular lens during the triple procedure results in better outcome of transplantation than ciliary sulcus placement of the IOL. Phacoemulsification allows removal of large nuclei through a 5 mm capsulorhexis without performing relaxing incisions out towards the periphery of the capsule.

 Keywords: corneal transplantation; graft survival; intraocular lens; triple procedure; visual acuity PMID:10434870

  11. Assessment of Intraocular and Systemic Vasculature Pressure Parameters in Simulated Microgravity with Thigh Cuff Countermeasure

    NASA Technical Reports Server (NTRS)

    Huang, Alex S.; Balasubramanian, Siva; Tepelus, Tudor; Sadda, Jaya; Sadda, Srinivas; Stenger, Michael B.; Lee, Stuart M. C.; Laurie, Steve S.; Liu, John; Macias, Brandon R.

    2017-01-01

    Changes in vision have been well documented among astronauts during and after long-duration space flight. One hypothesis is that the space flight induced headward fluid alters posterior ocular pressure and volume and may contribute to visual acuity decrements. Therefore, we evaluated venoconstrictive thigh cuffs as a potential countermeasure to the headward fluid shift-induced effects on intraocular pressure (IOP) and cephalic vascular pressure and volumes.

  12. Clinical, optical coherence tomography, and fundus autofluorescence findings in patients with intraocular tumors

    PubMed Central

    Samuelsson, Daniel; Sznage, Monika; Engelsberg, Karl; Wittström, Elisabeth

    2016-01-01

    Purpose To describe clinical, optical coherence tomography (OCT) and fundus autofluorescence (FAF) findings in patients with intraocular tumors and determine if OCT and FAF could be helpful in the differential diagnosis and management of different choroidal tumors. Methods Forty-nine patients with untreated, macular, midperipheral, and extrapapillary intraocular tumors were included. All patients underwent ophthalmic examination: best-corrected visual acuity, slit-lamp biomicroscopy, funduscopy, and standardized B mode, and if possible A mode, ultrasonography, and OCT and FAF imaging of the surface of the intraocular tumors. Results Of the 49 patients studied, 19 had choroidal nevi, ten had indeterminate choroidal melanocytic lesions (IMLs), ten had malignant melanomas, and ten had other choroidal tumors. The choroidal nevi revealed subretinal fluid (SRF) on OCT in only 11%. FAF detected isoauto-fluorescence in 42%, hypoautofluorescence in 37%, patchy FAF pattern in 16%, and a diffuse FAF pattern in 5%. Seventy percent of patients with IML showed SRF on OCT and 20% showed tumor growth on follow-up, detected only by OCT and FAF imaging. FAF revealed a patchy pattern in 50% and a diffuse pattern in 40% of cases with IML. Ninety percent of the patients with choroidal melanoma had SRF on OCT and FAF revealed a patchy pattern in 60% and a diffuse pattern in 40%. Patients with other choroidal tumors had SRF on OCT in 30% of cases and no characteristic pattern on FAF. Conclusion Both OCT and FAF were helpful in the differential diagnosis of choroidal nevi versus IMLs, choroidal melanomas, and other choroidal tumors. Also, detailed and periodical clinical evaluation of patients with intraocular tumors using OCT and FAF imaging for the detection of both SRF and FAF patterns overlying the tumor can be useful for detection of tumor growth. PMID:27784984

  13. Evaluation of Pharmacologic Agents to Suppress Intraocular Cellular Proliferation Following Trauma

    DTIC Science & Technology

    1986-07-01

    Treatment of intraocular proliferation with intravitreal injection of triamcinolone acetonide . Am J Ophthalmol 90:810, 1980. 9. Trese MT, Spitznas M... injected in the fashion for tractional retinal detachment model. The effects of triamcinolone seemed very comparable to dexamethasone with an...PG E 1 Prostaglandin PGE1 was injected in a 2 mg suspension into the vitreous cavity. Prostaglandin is a very unstable compound, and we assume has a

  14. Study of Variation in Intraocular Pressure Spike (IOP) Following Nd- YAG Laser Capsulotomy

    PubMed Central

    Sridhar, Sriya

    2016-01-01

    Introduction Posterior Capsular Opacifications (PCO) is a frequent complication of cataract surgery following posterior chamber intraocular lens implantation. Nd –Yag laser capsulotomy is the treatment of choice for PCO and is known to be associated with complications like Raised Intraocular Pressure (IOP), Intraocular lens pitting, intraocular lens cracks, cystoid macular oedema, retinal detachment, corneal burns. Raised IOP is the most common complication and prescribing anti-glaucoma drugs post capsulotomy is a common practise. Our study helps us to anticipate the post procedural IOP rise in specific patients and treat only selected group of patients with anti- glaucoma medications. Aim To study and correlate the effect of energy used and number of shots with post procedural IOP spike following Nd-YAG laser capsulotomy cases. Materials and Methods All patients with PCO presenting to Ophthalmology Out Patient Department at Sri Siddhartha Medical College between November 2014 to November 2015 were included. All the patients with glaucoma, uveitis and high myopia were excluded from the study. Data relevant to history, ocular examination and IOP were recorded. Results Significant correlation of IOP spike with the number of Nd- YAG Laser shots delivered was found by One-way ANOVA Post-Hoc Tukeys Test. The p-value was significant for shots more than 40, provided the energy was restricted to 20 mJ and below. Correlation of energy with IOP spike was not significant as found by One-way ANOVA, Post-Hoc Tukey test. Predictability of 2 hours post-procedure IOP regarding persistent IOP rise was significant. Conclusion It was observed that all pseudophakic patients may not require anti-glaucoma medication pre, or post Nd YAG laser capsulotomy. Only patients who required more than 40 shots during the procedure would need a close observation and if persistent rise is documented, ocular hypotensives may be advised. PMID:28208899

  15. Intraocular lens power estimation by accurate ray tracing for eyes underwent previous refractive surgeries

    NASA Astrophysics Data System (ADS)

    Yang, Que; Wang, Shanshan; Wang, Kai; Zhang, Chunyu; Zhang, Lu; Meng, Qingyu; Zhu, Qiudong

    2015-08-01

    For normal eyes without history of any ocular surgery, traditional equations for calculating intraocular lens (IOL) power, such as SRK-T, Holladay, Higis, SRK-II, et al., all were relativley accurate. However, for eyes underwent refractive surgeries, such as LASIK, or eyes diagnosed as keratoconus, these equations may cause significant postoperative refractive error, which may cause poor satisfaction after cataract surgery. Although some methods have been carried out to solve this problem, such as Hagis-L equation[1], or using preoperative data (data before LASIK) to estimate K value[2], no precise equations were available for these eyes. Here, we introduced a novel intraocular lens power estimation method by accurate ray tracing with optical design software ZEMAX. Instead of using traditional regression formula, we adopted the exact measured corneal elevation distribution, central corneal thickness, anterior chamber depth, axial length, and estimated effective lens plane as the input parameters. The calculation of intraocular lens power for a patient with keratoconus and another LASIK postoperative patient met very well with their visual capacity after cataract surgery.

  16. Quantifying intraocular scatter with near diffraction-limited double-pass point spread function

    PubMed Central

    Zhao, Junlei; Xiao, Fei; Kang, Jian; Zhao, Haoxin; Dai, Yun; Zhang, Yudong

    2016-01-01

    Measurement of the double-pass (DP) point-spread function (PSF) can provide an objective and non-invasive method for estimating intraocular scatter in the human eye. The objective scatter index (OSI), which is calculated from the DP PSF images, is commonly used to quantify intraocular scatter. In this article, we simulated the effect of higher-order ocular aberrations on OSI, and the results showed that higher-order ocular aberrations had a significant influence on OSI. Then we developed an adaptive optics DP PSF measurement system (AO-DPPMS) which was capable of correcting ocular aberrations up to eighth-order radial Zernike modes over a 6.0-mm pupil. Employing this system, we obtained DP PSF images of four subjects at the fovea. OSI values with aberrations corrected up to 2nd, 5th and 8th Zernike order were calculated respectively, from the DP PSF images of the four subjects. The experimental results were consistent with the simulation, suggesting that it is necessary to compensate for the higher-order ocular aberrations for accurate intraocular scatter estimation. PMID:27895998

  17. Optical aberrations of intraocular lenses measured in vivo and in vitro

    NASA Astrophysics Data System (ADS)

    Barbero, Sergio; Marcos, Susana; Jiménez-Alfaro, Ignacio

    2003-10-01

    Corneal and ocular aberrations were measured in a group of eyes before and after cataract surgery with spherical intraocular lens (IOL) implantation by use of well-tested techniques developed in our laboratory. By subtraction of corneal from total aberration maps, we also estimated the optical quality of the intraocular lens in vivo. We found that aberrations in pseudophakic eyes are not significantly different from aberrations in eyes before cataract surgery or from previously reported aberrations in healthy eyes of the same age. However, aberrations in pseudophakic eyes are significantly higher than in young eyes. We found a slight increase of corneal aberrations after surgery. The aberrations of the IOL and the lack of balance of the corneal spherical aberrations by the spherical aberrations of the intraocular lens also degraded the optical quality in pseudophakic eyes. We also measured the aberrations of the IOL in vitro, using an eye cell model, and simulated the aberrations of the IOL on the basis of the IOL's physical parameters. We found a good agreement among in vivo, in vitro, and simulated measures of spherical aberration: Unlike the spherical aberration of the young crystalline lens, which tends to be negative, the spherical aberration of the IOL is positive and increases with lens power. Computer simulations and in vitro measurements show that tilts and decentrations might be contributors to the increased third-order aberrations in vivo in comparison with in vitro measurements.

  18. Changes in blood pressure and sleep duration in patients with blue light-blocking/yellow-tinted intraocular lens (CHUKYO study).

    PubMed

    Ichikawa, Kazuo

    2014-07-01

    Blood pressure and sleep duration may be influenced by retinal light exposure. Cataracts may exert such an influence by decreasing the transparency of the crystalline lens. A large-scale clinical study was conducted to examine changes in blood pressure and sleep duration after intraocular lens (IOL) implantation during cataract surgery and to investigate how different types of IOL influence the degree of these effects. Using a questionnaire, we collected information, including blood pressure measurement and sleep duration, from 1367 patients (1367 eyes) before IOL implantation, 1 week after IOL implantation and 1 month after IOL implantation. Systolic and diastolic blood pressures were significantly decreased in the total patient group after implantation. The decrease in systolic blood pressure 1 month after implantation was significantly more in patients who received a yellow-tinted IOL than it was in those who received an ultraviolet (UV) light-filtering IOL. The post-implantation sleep duration, including naps, became shorter in patients who had slept too much and became longer in those who had slept too little before IOL implantation. Our observations suggest that a yellow-tinted IOL is better for patients with high blood pressure than a UV light-filtering IOL. Furthermore, the yellow-tinted IOL is as good as the UV light-filtering IOL for improving sleep duration. A pale yellow-tinted IOL is likely to be superior to a moderate yellow-tinted IOL in terms of allowing patients to discriminate different colors. Thus, the pale yellow-tinted IOL appears to be better for patients than the UV light-filtering IOL and the moderate yellow-tinted IOL.

  19. Alterations of the synapse of the inner retinal layers after chronic intraocular pressure elevation in glaucoma animal model

    PubMed Central

    2014-01-01

    Background Dendrites of retinal ganglion cells (RGCs) synapse with axon terminals of bipolar cells in the inner plexiform layer (IPL). Changes in RGC dendrites and synapses between bipolar cells in the inner retinal layer may critically alter the function of RGCs in glaucoma. Recently, synaptic plasticity has been observed in the adult central nervous system, including the outer retinal layers. However, few studies have focused on changes in the synapses between RGCs and bipolar cells in glaucoma. In the present study, we used a rat model of ocular hypertension induced by episcleral vein cauterization to investigate changes in synaptic structure and protein expression in the inner retinal layer at various time points after moderate intraocular pressure (IOP) elevation. Results Synaptophysin, a presynaptic vesicle protein, increased throughout the IPL, outer plexiform layer, and outer nuclear layer after IOP elevation. Increased synaptophysin after IOP elevation was expressed in bipolar cells in the innermost IPL. The RGC marker, SMI-32, co-localized with synaptophysin in RGC dendrites and were significantly increased at 1 week and 4 weeks after IOP elevation. Both synaptophysin and postsynaptic vesicle protein, PSD-95, were increased after IOP elevation by western blot analysis. Ribbon synapses in the IPL were quantified and structurally evaluated in retinal sections by transmission electron microscopy. After IOP elevation the total number of ribbon synapses decreased. There were increases in synapse diameter and synaptic vesicle number and decreases in active zone length and the number of docked vesicles after IOP elevation. Conclusions Although the total number of synapses decreased as RGCs were lost after IOP elevation, there are attempts to increase synaptic vesicle proteins and immature synapse formation between RGCs and bipolar cells in the inner retinal layers after glaucoma induction. PMID:25116810

  20. Axial movement of the dual-optic accommodating intraocular lens for the correction of the presbyopia: Optical performance and clinical outcomes

    PubMed Central

    Tomás-Juan, Javier; Murueta-Goyena Larrañaga, Ane

    2014-01-01

    Presbyopia occurs in the aging eye due to changes in the ciliary muscle, zonular fibers, crystalline lens, and an increased lens sclerosis. As a consequence, the capacity of accommodation decreases, which hampers to focus near objects. With the aim of restoring near vision, different devices that produce multiple focuses have been developed and introduced. However, these devices are still unable to restore accommodation. In order to achieve that goal, dual-optic accommodating Intraocular Lenses have been designed, whose anterior optic displaces axially to increase ocular power, and focus near objects. Although dual-optic accommodating IOLs are relatively new, their outcomes are promising, as they provide large amplitudes of accommodation and a greater IOL displacement than single-optic accommodating IOLs. The outcomes show comfortable near vision, higher patients’ satisfaction rates, and minimal postoperative complications like Posterior Capsular Opacification and Anterior Capsular Opacification, due to their design and material. PMID:25248803

  1. Learning by Doing, Creating a Museum Exhibit.

    ERIC Educational Resources Information Center

    Main, Sarah; Kallquist, Dierdre

    2000-01-01

    Describes an exhibit called Kid's Kitchen, built within a major exhibit called Biodiversity: Life Supporting Life, in order to discuss environmental prompts hidden within the kitchen designed to surprise students and get them thinking. (ASK)

  2. Science Education Through a Museum Exhibit

    ERIC Educational Resources Information Center

    Chaparian, Azad; And Others

    1973-01-01

    Describes the polywater exhibit at the Worcester Science Center in Massachusetts. Curiosity and interest are stimulated in young people by allowing them to handle the materials in the exhibit and by providing them with instructions for making polywater. (JR)

  3. Effect of persistent high intraocular pressure on microstructure and hydraulic permeability of trabecular meshwork

    NASA Astrophysics Data System (ADS)

    Mei, Xi; Ren, Lin; Xu, Qiang; Zheng, Wei; Liu, Zhi-Cheng

    2015-05-01

    As the aqueous humor leaves the eye, it first passes through the trabecular meshwork (TM). Increased flow resistance in this region causes elevation of intraocular pressure (IOP), which leads to the occurrence of glaucoma. To quantitatively evaluate the effect of high IOP on the configuration and hydraulic permeability of the TM, second harmonic generation (SHG) microscopy was used to image the microstructures of the TM and adjacent tissues in control (normal) and high IOP conditions. Enucleated rabbit eyes were perfused at a pressure of 60 mmHg to achieve the high IOP. Through the anterior chamber of the eye, in situ images were obtained from different depths beneath the surface of the TM. Porosity and specific surface area of the TM in control and high IOP conditions were then calculated to estimate the effect of the high pressure on the permeability of tissue in different depths. We further photographed the histological sections of the TM and compared the in situ images. The following results were obtained in the control condition, where the region of depth was less than 55 μm with crossed branching beams and large pores in the superficial TM. The deeper meshwork is a silk-like tissue with abundant fluorescence separating the small size of pores. The total thickness of pathway tissues composed of TM and juxtacanalicular (JCT) is more than 100 μm. After putting a high pressure on the inner wall of the eye, the TM region progressively collapses and decreases to be less than 40 μm. Fibers of the TM became dense, and the porosity at 34 μm in the high IOP condition is comparable to that at 105 μm in the control condition. As a consequent result, the permeability of the superficial TM decreases rapidly from 120 μm2 to 49.6 μm2 and that of deeper TM decreases from 1.66 μm2 to 0.57 μm2. Heterogeneity reflected by descent in permeability reduces from 12.4 μm of the control condition to 3.74 μm of the high IOP condition. The persistently high IOP makes the TM

  4. 29 CFR 2200.70 - Exhibits.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... prohibits its convenient transportation and storage. A party may offer into evidence photographs, models or... separate file designated for rejected exhibits. (e) Return of physical exhibits. A party may on motion request the return of a physical exhibit within 30 days after expiration of the time for filing a...

  5. Toxicity and Intraocular Properties of a Novel Long-Acting Anti-Proliferative and Anti-Angiogenic Compound IMS2186

    PubMed Central

    Falkenstein, Iryna A.; Cheng, Lingyun; Wong-Staal, Flossie; Tammewar, Ajay M.; Barron, Erin C.; Silva, Gabriel A.; Li, Qi-Xiang; Yu, Dehua; Hysell, Michelle; Liu, Guohong; Ke, Ning; Macdonald, James E.; Freeman, William R.

    2009-01-01

    Purpose To investigate the intraocular properties and toxicity of IMS2186, a small molecule developed as an anti-choroidal neovascularization (anti-CNV) drug. Materials and Methods Cellular toxicity and mechanism of action was tested on cell lines in vitro. Intraocular studies used rabbits for drug dissolution as well as toxicity and rats for the treatment study as well as the toxicity confirmation study. Rabbits' eyes were injected with 2.5 mg of IMS2186 and observed for 36 weeks. Laser-induced CNV in rats was treated with IMS2186, Kenalog, or phosphate-buffered saline (pBS). Fluorescein angiography (FA) and immunohistochemical processing of the globes was performed. Results The anti-proliferative IC50 of IMS2186 for human fibroblast cells was 1.0–3.0 μM and 0.3–3.0 μM for human cancer cells; the IC50 of IMS2186 to inhibit endothelial tube formation was 0.1–0.3 μM. The IC50 of IMS2186 for inhibiting the production of pro-inflammatory cytokines was 0.3–1 μM. The IC50 of IMS2186 for inhibiting macrophage migration was 1 μM. These biological properties were not species specific. IMS2186 can be formulated as a suspension for long-lasting release and when delivered intraocularly, no intraocular toxicity was observed by slit lamp exam, fundus exam, intraocular pressure measurements, or by electroretinography. FA showed a reduction in the leakage in eyes treated with IMS2186 and triamcinolone acetonide; DAPI staining also showed significantly less cellularity in IMS2186-treated lesions as compared to PBS (p = 0.0025). Conclusion IMS2186 may be a safe intraocular therapeutic agent for intraocular proliferation and angiogenesis. PMID:18600493

  6. Development of Exhibit on Arctic Climate Change Called The Arctic: A Friend Acting Strangely Exhibition

    SciTech Connect

    Stauffer, Barbara W.

    2006-04-01

    The exhibition, The Arctic: A Friend Acting Strangely, was developed at the Smithsonian Institution’s National Museum of Natural History (NMNH) as a part of the museum’s Forces of Change exhibit series on global change. It opened to the public in Spring 2006, in conjunction with another Forces of Change exhibit on the Earth’s atmosphere called Change Is in the Air. The exhibit was a 2000 square-foot presentation that explored the forces and consequences of the changing Arctic as documented by scientists and native residents alike. Native peoples of the Arctic have always lived with year-to-year fluctuations in weather and ice conditions. In recent decades, they have witnessed that the climate has become unpredictable, the land and sea unfamiliar. An elder in Arctic Canada recently described the weather as uggianaqtuq —an Inuit word that can suggest strange, unexpected behavior, sometimes described as that of “a friend acting strangely.” Scientists too have been documenting dramatic changes in the Arctic. Air temperatures have warmed over most—though not all—of the Arctic since the 1950s; Arctic precipitation may have increased by as much as 8%; seasonal melting of the Greenland Ice Sheet has increased on average by 16% since 1979; polar-orbiting satellites have measured a 15¬–20% decline in sea ice extent since the 1970s; aircraft reconnaissance and ship observations show a steady decrease in sea ice since the 1950s. In response to this warming, plant distributions have begun to shift and animals are changing their migration routes. Some of these changes may have beneficial effects while others may bring hardship or have costly implications. And, many scientists consider arctic change to be a ‘bell-weather’ for large-scale changes in other regions of the world. The exhibition included text, photos artifacts, hands-on interactives and other exhibitry that illustrated the changes being documented by indigenous people and scientists alike.

  7. A technique of experimental and numerical analysis of influence of defects in the intraocular lens on the retinal image quality

    NASA Astrophysics Data System (ADS)

    Geniusz, Malwina; ZajÄ c, Marek

    2016-09-01

    Intraocular lens (IOL) is an artificial lens implanted into the eye in order to restore correct vision after the removal of natural lens cloudy due to cataract. The IOL prolonged stay in the eyeball causes the creation of different changes on the surface and inside the implant mainly in form of small-size local defects such as vacuoles and calcium deposites. Their presence worsens the imaging properties of the eye mainly due to occurence of scattered light thus deteriorating the vision quality of patients after cataract surgery. It is very difficult to study influence the effects of these changes on image quality in real patients. To avoid these difficulties two other possibilities were chosen: the analysis of the image obtained in an optomechanical eye model with artificially aged IOL as well as numerical calculation of the image characteristics while the eye lens is burdened with adequately modeled defects. In experiments the optomechanical model of an eye consisting of a glass "cornea", chamber filled with liquid where the IOL under investigation was inserted and a high resulution CCC detector serving as a "retina" was used. The Modulation Transfer Function (MTF) of such "eye" was evaluated on the basis of image of an edge. Experiments show that there is significant connection between ageing defects and decrease in MTF parameters. Numerical part was performed with a computer programme for optical imaging analysis (OpticStudio Professional, Zemax Professional from Radiant Zemax, LLC). On the basis of Atchison eye model with lens burdened with defects Modulation Transfer Functio was calculated. Particular parameters of defects used in a numerical model were based on own measurements. Numerical simulation also show significant connection between ageing defects and decrease of MTF parameters. With this technique the influence of types, density and distribution of local defect in the IOL on the retinal image quality can be evaluated quickly without the need of

  8. Effects of inner materials on the sensitivity and phase depth of wireless inductive pressure sensors for monitoring intraocular pressure

    NASA Astrophysics Data System (ADS)

    Jang, Cheol-In; Shin, Kyeong-Sik; Kim, Mi Jeung; Yun, Kwang-Seok; Park, Ki Ho; Kang, Ji Yoon; Lee, Soo Hyun

    2016-03-01

    In this research, we developed wireless, inductive, pressure sensors with high sensitivity and investigated the effects of the inner materials (copper or ferrite) on the performance of the sensors. The proposed sensor is comprised of two parts, i.e., the top and the bottom parts. The top part includes a micro coil and a capacitor for the wireless transfer of data, and the bottom part includes the inner materials and a thick or thin flexible membrane to induce changes in the inductance. An anchor is used to assemble the top and bottom parts. The behavior of the sensor with copper was based on the eddy current effect, and, as the pressure increased, its resonance frequency increased, while its phase depth decreased exponentially. The principle of the sensor with ferrite was related to the effective permeability between a ferrite and a coil, and its response was the opposite of that with copper, i.e., as the pressure increased, the resonance frequency decreased linearly, and the phase depth increased linearly. These different operational mechanisms can be explained by the changes in the equations of inductance presented in this paper. After characterizing four different types of inductive pressure sensors in ambient air, one type of inductive pressure sensor was used to monitor the intraocular pressure (IOP) of a rabbit's eye as a biomedical application. The results showed that, in the animal tests, the measured responsivity and sensitivity were 16.7 kHz/mmHg and 1340 ppm/mmHg, respectively. These data indicate that the proposed sensor is a good candidate for monitoring IOP.

  9. Possible involvement of nitric oxide in morphine-induced miosis and reduction of intraocular pressure in rabbits.

    PubMed

    Bonfiglio, Vincenza; Bucolo, Claudio; Camillieri, Giovanni; Drago, Filippo

    2006-03-18

    The role of mu3 opioid receptors in morphine-induced intraocular pressure (IOP) lowering effect and miosis was evaluated in conscious, dark-adapted New Zealand white (NZW) rabbits using a masked-design study. IOP and pupil diameter (PD) measurements were taken at just before and 0.5, 1, 2, 4, 6 h after monolateral instillation of morphine (10, 50 and 100 microg/30 microl) as compared to vehicle administered in the contralateral eye. Morphine-induced ocular effects were challenged by a pre-treatment with the non-selective opioid receptor antagonist, naloxone (100 microg/30 microl), the nitric oxide synthase inhibitor, N(omega)-nitro-L-arginine methyl ester (L-NAME, 1%, 30 microl), or the non-selective mu3 opioid receptor inhibitor, reduced L-glutathione (GSH, 1%, 30 microl). Morphine induced a dose-dependent decrease in IOP and PD. Pre-treatment with naloxone totally prevented morphine-induced decrease in IOP and miosis. Ocular administration of L-NAME or GSH alone failed to affect IOP or PD of NZW rabbits. However, pre-treatment with either drugs significantly reduced, but not totally prevented ocular effects of morphine. These results suggest that biochemical mechanisms related to nitric oxide release are involved, at least in part, in morphine effects on the eye. Since the mu3 opioid receptor subtype is able to release nitric oxide and is sensitive to inactivation by GSH, it may be possible that mu3 opioid receptors are involved in morphine-induced miosis and reduction in IOP.

  10. Space exhibitions: the science encounters the public

    NASA Astrophysics Data System (ADS)

    Coliolo, F.; Menendez, M.

    The widespread dissemination of science has always been one pillar of the development of human knowledge. There are several methods to structure interaction with the public: media, conferences, various written genres, and exhibitions. But: how to attract the public? How to arouse interest among future generation, insatiable for knowledge? In this paper we focus on space exhibitions, whose content combines mystery, discovery and science. The preparation of an exhibition is based on guidelines discussed between an interdisciplinary team and the exhibition project manager, the purpose of which is to find a coherent "strategy" to select information and to choose a concise, efficient, smart and original way to "visualize" the messages. Exhibition visitors are "privileged" because the interactivity is first emotive, then mental and cultural; the audience is universal. The goal of an exhibition is not to explain the content, but to stimulate the audience's curiosity in an attractive environment. We show some photos of ESA exhibitions, and try to understand if the visual impact is the first step towards a "multi-sensory" approach to communication. "A good exhibition can never be replaced by a book, a film or a lecture. A good exhibition creates a thirst for books, film, lectures. A good exhibition changes the visitors"(J. Wagensberg, Modern scientific museology")

  11. Exhibition of Stochastic Resonance in Vestibular Perception

    NASA Technical Reports Server (NTRS)

    Galvan-Garza, R. C.; Clark, T. K.; Merfeld, D. M.; Bloomberg, J. J.; Oman, C. M.; Mulavara, A. P.

    2016-01-01

    Astronauts experience sensorimotor changes during spaceflight, particularly during G-transitions. Post flight sensorimotor changes include spatial disorientation, along with postural and gait instability that may degrade operational capabilities of the astronauts and endanger the crew. A sensorimotor countermeasure that mitigates these effects would improve crewmember safety and decrease risk. The goal of this research is to investigate the potential use of stochastic vestibular stimulation (SVS) as a technology to improve sensorimotor function. We hypothesize that low levels of SVS will improve sensorimotor perception through the phenomenon of stochastic resonance (SR), when the response of a nonlinear system to a weak input signal is enhanced by the application of a particular nonzero level of noise. This study aims to advance the development of SVS as a potential countermeasure by 1) demonstrating the exhibition of stochastic resonance in vestibular perception, a vital component of sensorimotor function, 2) investigating the repeatability of SR exhibition, and 3) determining the relative contribution of the semicircular canals (SCC) and otolith (OTO) organs to vestibular perceptual SR. A constant current stimulator was used to deliver bilateral bipolar SVS via electrodes placed on each of the mastoid processes, as previously done. Vestibular perceptual motion recognition thresholds were measured using a 6-degree of freedom MOOG platform and a 150 trial 3-down/1-up staircase procedure. In the first test session, we measured vestibular perceptual thresholds in upright roll-tilt at 0.2 Hz (SCC+OTO) with SVS ranging from 0-700 µA. In a second test session a week later, we re-measured roll-tilt thresholds with 0, optimal (from test session 1), and 1500 µA SVS levels. A subset of these subjects, plus naive subjects, participated in two additional test sessions in which we measured thresholds in supine roll-rotation at 0.2 Hz (SCC) and upright y-translation at 1 Hz

  12. Marine bacteria exhibit a bipolar distribution.

    PubMed

    Sul, Woo Jun; Oliver, Thomas A; Ducklow, Hugh W; Amaral-Zettler, Linda A; Sogin, Mitchell L

    2013-02-05

    The microbial cosmopolitan dispersion hypothesis often invoked to explain distribution patterns driven by high connectivity of oceanographic water masses and widespread dispersal ability has never been rigorously tested. By using a global marine bacterial dataset and iterative matrix randomization simulation, we show that marine bacteria exhibit a significantly greater dispersal limitation than predicted by our null model using the "everything is everywhere" tenet with no dispersal limitation scenario. Specifically, marine bacteria displayed bipolar distributions (i.e., species occurring exclusively at both poles and nowhere else) significantly less often than in the null model. Furthermore, we observed fewer taxa present in both hemispheres but more taxa present only in a single hemisphere than expected under the null model. Each of these trends diverged further from the null expectation as the compared habitats became more geographically distant but more environmentally similar. Our meta-analysis supported a latitudinal gradient in bacterial diversity with higher richness at lower latitudes, but decreased richness toward the poles. Bacteria in the tropics also demonstrated narrower latitudinal ranges at lower latitudes and relatively larger ranges in higher latitudes, conforming to the controversial macroecological pattern of the "Rapoport rule." Collectively, our findings suggest that bacteria follow biogeographic patterns more typical of macroscopic organisms, and that dispersal limitation, not just environmental selection, likely plays an important role. Distributions of microbes that deliver critical ecosystem services, particularly those in polar regions, may be vulnerable to the same impacts that environmental stressors, climate warming, and degradation in habitat quality are having on biodiversity in animal and plant species.

  13. Waves in geomaterials exhibiting negative stiffness behaviour

    NASA Astrophysics Data System (ADS)

    Esin, Maxim; Dyskin, Arcady; Pasternak, Elena

    2016-04-01

    Negative stiffness denotes the type of material behaviour when the force applied to the body decreases the body's deformation increases. Some geomaterials, for instance, rocks, demonstrate behaviour of this type at certain loads: during the compression tests the loading curves exhibit descending branch (post-peak softening). One of the possible mechanisms of the negative stiffness appearance in geomaterials is rotation of non-spherical grains. It is important to emphasize that in this case the descending branch may be reversible given that the testing machine is stiff enough (in general case it means an importance of boundary conditions). Existence of geomaterials with a negative modulus associated with rotations may have significant importance. In particular, important is understanding of the wave propagation in such materials. We study the stability of geomaterials with negative stiffness inclusions and wave propagation in it using two approaches: Cosserat continuum and discrete mass-spring models. In both cases we consider the rotational degrees of freedom in addition to the conventional translational ones. We show that despite non positiveness of the energy the materials with negative stiffness elements can be stable if certain conditions are met. In the case of Cosserat continuum the Cosserat shear modulus (the modulus relating the non-symmetrical part of shear stress and internal rotations) is allowed to assume negative values as long as its value does not exceed the value of the standard (positive) shear modulus. In the case of discrete mass-spring systems (with translational and rotational springs) the concentration of negative stiffness springs and the absolute values of negative spring stiffness are limited. The critical concentration when the system loses stability and the amplitude of the oscillations tends to infinity is equal to 1/2 and 3/5 for two- and three-dimensional cases respectively.

  14. Superconductive microstrip exhibiting negative differential resistivity

    DOEpatents

    Huebener, R.P.; Gallus, D.E.

    1975-10-28

    A device capable of exhibiting negative differential electrical resistivity over a range of values of current and voltage is formed by vapor- depositing a thin layer of a material capable of exhibiting superconductivity on an insulating substrate, establishing electrical connections at opposite ends of the deposited strip, and cooling the alloy into its superconducting range. The device will exhibit negative differential resistivity when biased in the current- induced resistive state.

  15. Effect of prophylactic intraocular pressure-lowering medication (brinzolamide) on intraocular pressure after ranibizumab intravitreal injection: A case–control study

    PubMed Central

    Song, Shuang; Yu, Xiao-bing; Dai, Hong

    2016-01-01

    Purpose: To observe the effect of prophylactic intraocular pressure (IOP)-lowering medication (brinzolamide) on IOP after ranibizumab intravitreal injections (IVIs). Materials and Methods: This prospective case–control study included 352 eyes from 352 patients (1 eye per patient) who were treated with ranibizumab intravitreal injection and divided randomly into two groups. Two hundred and three patients in control group only received the ranibizumab IVI, but 149 patients in case group received one drop of prophylactic intraocular brinzolamide preinjection. The IOP was measured by noncontact tonometer before injection, at 10, 30, 120 min and 1 day after injection in a sitting position. Results: The mean IOP measured before injection, at 10, 30, 120 min and 1 day after injection individually were 15.79 ± 2.21 mmHg, 19.33 ± 4.86 mmHg, 16.64 ± 2.93 mmHg, 16.17 ± 3.13 mmHg, and 15.07 ± 2.55 mmHg in case group and were 15.82 ± 2.57 mmHg, 21.34 ± 5.88 mmHg, 18.17 ± 4.06 mmHg, 17.59 ± 4.42 mmHg, and15.48 ± 2.92 mmHg in control group. Comparing two groups, the mean increase on IOP was statistically significant at 10, 30, 120 min postinjection (P < 0.05). Conclusions: IVI of ranibizumab causes a considerable short-term transient rise on IOP in most patients. The effect of prophylactic IOP-lowering medication on IOP after IVIs can be statistically significant from 10 min to 2 h after IVIs. PMID:27905340

  16. Alfaxalone versus propofol in dogs: a randomised trial to assess effects on peri-induction tear production, intraocular pressure and globe position.

    PubMed

    Costa, Daniel; Leiva, Marta; Moll, Xavier; Aguilar, Adrià; Peña, Teresa; Andaluz, Anna

    2015-01-17

    The purpose of this randomised trial was to compare the effects of alfaxalone and propofol on tear production (STT-1), intraocular pressure (IOP) and globe position (GP) in healthy dogs. Fourteen Beagles were randomly divided into two groups; dogs in one group received alfaxalone (3 mg/kg) (n=7) and dogs in the other group received propofol (6 mg/kg) (n=7), both administered intravenously. IOP and GP were evaluated at basal time (Tb) and T2,5,10,15,20,25&30 (minutes after complete drug administration). STT-1 was evaluated at Tb and T10,20&30. STT-1 and IOP results were analysed using analysis of variance and GP was analysed using the likelihood ratio χ(2) test. Dogs in the alfaxalone group showed a significant reduction in STT-1 at T10&20 (P<0.05), while the propofol group did not show statistically significant differences in this parameter over time. Both anaesthetic drugs produced a transient elevation of IOP at T2 (P>0.05), which then decreased (P<0.01). While alfaxalone caused a ventral globe deviation that lasted from T2 to T10 (P<0.05) and was fully recovered at T30, propofol induced a ventral globe deviation from T2 to T5 (P<0.05), being restored at T20. These results suggest that both alfaxalone and propofol can be safely used for intraocular surgery, as they significantly reduce IOP. Furthermore, anaesthetic induction with propofol would be especially recommended for dogs with tear deficiencies.

  17. [Reliable UV-light protection in intraocular lenses--scientific rationale and quality requirements].

    PubMed

    Augustin, A J

    2014-09-01

    Since the late 1980s implantation of UV-blocker intraocular lenses during cataract surgery has become an internationally accepted standard. Last year the Kassenärztliche Vereinigung Bayern (KVB) and statutory health insurance organisations proposed for the first time quality criteria for intraocular lenses (IOL), thereby including exact parameters for the amount of UV light transmission (≤10% at 400 nm). Since then, the discussion has been raised again as to what extent IOLs should filter or block UV light. In this article, exact definitions of spectral subbands within the optical radiation band are given. Today, 400 nm is the internationally accepted standard to distinguish UV light and visible light. Moreover, exposure of the eye to UV radiation is described as well as mechanisms of photooxidative damage to the retina. Comprehensive laboratory and animal experimental studies show that light of short wave lengths, i.e., above all UV light but also blue light, may induce photochemical damage to the retina. Primary sites of such damage are both the outer segments of the photoreceptors and the retinal pigment epithelium (RPE). Physiological protective mechanisms of the eye, such as filtering properties of different ocular media are described in detail. Cornea, aqueous and vitreous absorb UV radiation below 300 nm, while the natural adult lens absorbs UV radiation between 300 and 400 nm. This protection is lost when the lens is removed by cataract surgery and thus should be restored. UV light does not contribute to vision but damages retinal structures. Therefore, UV-blocking intraocular lenses with a 10% cut-off near 400 nm should be implanted during cataract surgery. This ensures sufficient retinal protection after surgery. These theoretical considerations are supported by results from animal and clinical studies.

  18. Genome-wide association study of intraocular pressure identifies the GLCCI1/ICA1 region as a glaucoma susceptibility locus

    PubMed Central

    Strange, Amy; Bellenguez, Céline; Sim, Xueling; Luben, Robert; Hysi, Pirro G.; Ramdas, Wishal D.; van Koolwijk, Leonieke M.E.; Freeman, Colin; Pirinen, Matti; Su, Zhan; Band, Gavin; Pearson, Richard; Vukcevic, Damjan; Langford, Cordelia; Deloukas, Panos; Hunt, Sarah; Gray, Emma; Dronov, Serge; Potter, Simon C.; Tashakkori-Ghanbaria, Avazeh; Edkins, Sarah; Bumpstead, Suzannah J.; Blackwell, Jenefer M.; Bramon, Elvira; Brown, Matthew A.; Casas, Juan P.; Corvin, Aiden; Duncanson, Audrey; Jankowski, Janusz A.Z.; Markus, Hugh S.; Mathew, Christopher G.; Palmer, Colin N.A.; Plomin, Robert; Rautanen, Anna; Sawcer, Stephen J.; Trembath, Richard C.; Wood, Nicholas W.; Barroso, Ines; Peltonen, Leena; Healey, Paul; McGuffin, Peter; Topouzis, Fotis; Klaver, Caroline C.W.; van Duijn, Cornelia M.; Mackey, David A.; Young, Terri L.; Hammond, Christopher J.; Khaw, Kay-Tee; Wareham, Nick; Wang, Jie Jin; Wong, Tien Y.; Foster, Paul J.; Mitchell, Paul; Spencer, Chris C.A.; Donnelly, Peter; Viswanathan, Ananth C.

    2013-01-01

    To discover quantitative trait loci for intraocular pressure, a major risk factor for glaucoma and the only modifiable one, we performed a genome-wide association study on a discovery cohort of 2175 individuals from Sydney, Australia. We found a novel association between intraocular pressure and a common variant at 7p21 near to GLCCI1 and ICA1. The findings in this region were confirmed through two UK replication cohorts totalling 4866 individuals (rs59072263, Pcombined = 1.10 × 10−8). A copy of the G allele at this SNP is associated with an increase in mean IOP of 0.45 mmHg (95%CI = 0.30–0.61 mmHg). These results lend support to the implication of vesicle trafficking and glucocorticoid inducibility pathways in the determination of intraocular pressure and in the pathogenesis of primary open-angle glaucoma. PMID:23836780

  19. A new surgical technique using steel suture for trans-scleral fixation of posterior chamber intraocular lenses

    PubMed Central

    Ram, Jagat; Gupta, Nishant; Chaudhary, Manish; Verma, Neelam

    2013-01-01

    Background: A new emerging complication of trans-scleral fixation of posterior chamber (PC) intraocular lens (IOL) with polypropylene suture is high rates of spontaneous dislocation of the IOL due to disintegration or breakage of suture. Materials: We report a new surgical technique of trans-scleral fixation of posterior chamber intraocular lens (SF PCIOL) with steel suture to eliminate the complication of dislocation of IOL fixed with polypropylene suture in one adult and a child. Results: We successfully achieved stable fixation and good centration of IOL after SF PCIOL with steel suture in these patient having inadequate posterior capsular support. Both eyes achieved best corrected visual acuity 20/40 at 18 months follow-up. Conclusions: Steel suture is a viable option for trans-scleral fixation of posterior chamber intraocular lens. PMID:23619504

  20. Encountering Nanotechnology in an Interactive Exhibition

    ERIC Educational Resources Information Center

    Murriello, Sandra E.; Knobel, Marcelo

    2008-01-01

    This article offers findings from a learning sciences-informed evaluation of a nanoscience and nanotechnology exhibition called Nano-Aventura (NanoAdventure), based on four interactive-collaborative games and two narrated videos. This traveling exhibition was developed in Brazil by the Museu Exploratorio de Ciencias for children and teenagers…

  1. Learning4Life on the Exhibit Floor

    ERIC Educational Resources Information Center

    Sullivan, Margaret

    2009-01-01

    The exhibit floor is a wealth of knowledge. One can read, view, and listen to information presented in many formats. Somewhere on the exhibit floor there are experts on every topic, ready and waiting for one's questions. But like any research topic, frequently a structured search is required to find the best answers. This article discusses how to…

  2. Evaluation of Clientele Impact of Science Exhibits.

    ERIC Educational Resources Information Center

    Talisayon, Vivien M.

    1998-01-01

    Explores the use of an impact evaluation model across time and clientele groups that is used to evaluate exhibits from two science centers in Manila. Questionnaire and interview data indicate that students prefer exhibits that produce sound, light, and motion. (DDR)

  3. 49 CFR 250.2 - Required exhibits.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... statement, together with supporting evidence, that the probable value of the assets of the railroad in the... carrier's existing railroad. (5) As Exhibit 5, statement showing miles of line owned; miles operated... carried; and identification of the ten most important industries served. (6) As Exhibit 6, statement as...

  4. Science Fiction Exhibits as STEM Gateways

    NASA Astrophysics Data System (ADS)

    Robie, Samantha

    Women continue to hold less than a quarter of all STEM jobs in the United States, prompting many museums to develop programs and exhibits with the express goal of interesting young girls in scientific fields. At the same time, a number of recent museum exhibits have harnessed the popularity of pop culture and science fiction in order to interest general audiences in STEM subject matter, as well as using the exhibits as springboards to expand or shift mission goals and focus. Because science fiction appears to be successful at raising interest in STEM fields, it may be an effective way to garner the interest of young girls in STEM in particular. This research seeks to describe the ways in which museums are currently using science fiction exhibits to interest young girls in STEM fields and careers. Research focused on four institutions across the country hosting three separate exhibits, and included staff interviews and content analysis of exhibit descriptions, promotional materials, a summative evaluation and supplementary exhibit productions. In some ways, science fiction exhibits do serve young girls, primarily through the inclusion of female role models, staff awareness, and prototype testing to ensure interactives are attractive to girls as well as to boys. However, STEM appears to be underutilized, which may be partly due to a concern within the field that the outcome of targeting a specific gender could be construed as "stereotyping".

  5. Strategies for Determining Exhibit Effectiveness. Final Report.

    ERIC Educational Resources Information Center

    Shettel, Harris H.; And Others

    This project was designed to develop research strategies and hypotheses for evaluating the effectiveness of exhibits. An exhibit on the role of the Federal Government in science and technology was used as the subject matter. Two basic groups of viewers were used, casual viewers and paid experimental viewers. Both were tested on knowledge gained…

  6. The “correct shake” for “handshake” in glued intrascleral fixation of intraocular lens

    PubMed Central

    Narang, Priya; Agarwal, Amar

    2016-01-01

    We hereby describe the correct method to perform a “handshake technique” and easy transfer of haptics from one hand to another for glued intrascleral fixation of an intraocular lens (glued IOL). The procedure was implemented in 57 cases that necessitated the application of performing a glued IOL procedure and it resulted in an appropriate and easy externalization of haptic in all the cases. The surgeons’ positioning with reference to the scleral flap is an essential component and the surgeon should always be positioned perpendicular to the plane of scleral flaps and the plane of haptic maneuver. The surgeons who intend to perform glued IOL should adopt this technical point. PMID:27958214

  7. Orbital metallic mesh causing chronic intraocular foreign body and restrictive strabismus.

    PubMed

    Hwang, Catherine J; Katowitz, William R; Volpe, Nicholas J

    2007-01-01

    A 51-year-old woman with a history of a left orbital floor fracture repaired with stainless steel mesh in 1973 presented for evaluation of chronic head tilt and strabismus. Ocular motility examination revealed severely restricted eye movements with a large-angle esotropia and left hypotropia, and positive forced ductions. Dilated fundoscopic examination was notable for a small metal wire surrounded by hyperpigmentation in the inferonasal quadrant. CT confirmed globe penetration by the mesh floor implant. Although treatment options were contemplated, after further review, observation was chosen. This is a rare case of wire mesh causing a well-tolerated metallic intraocular foreign body and strabismus.

  8. Unusual intraocular foreign bodies after an explosion: patient's hand bone fragments.

    PubMed

    Sonmez, Murat; Duzgun, E; Yildirim, Y; Ayata, A; Unal, M H

    2016-04-01

    A 26-year-old Turkish Army soldier underwent full ophthalmoscopic examination after a penetrating ocular injury in the left eye due to the accidental explosion of a detonating fuse during handling. Visual acuity of the left eye was hand motion level. Funduscopy revealed foreign bodies suspended in the vitreous gel and accompanying vitreous haemorrhage. B-scan ultrasonography, CT of the orbits and microscopic examination of the intraocular foreign bodies (IOFBs) were performed prior to removal of bone fragments and pars plana vitrectomy. The IOFBs were fragments of the patients' bone tissue. Bone fragments from victim's body may cause IOFBs after an explosion in military personnel.

  9. Intraocular lens confusions: a preventable "never event" - The Royal Victorian Eye and Ear Hospital protocol.

    PubMed

    Zamir, Ehud; Beresova-Creese, Katarina; Miln, Linda

    2012-09-01

    Intraocular lens (IOL) confusions and errors are among the most common postoperative adverse events. Errors may occur at any stage from the decision to operate to the insertion of the IOL. The most common errors occur during IOL selection pre-operative preparation (anaesthesia given before recognition that the intended IOL is not available), or intraoperatively (wrong IOL implanted because of confusion in the operating room). We review the mechanisms of errors reported in the literature and describe the experience at The Royal Victorian Eye and Ear Hospital. We also describe the implementation of an error-detection protocol and provide qualitative data on its performance.

  10. Regulation of intraocular pressure and pupil size by beta-blockers and epinephrine.

    PubMed

    Ohrström, A; Pandolfi, M

    1980-12-01

    The interaction of adrenergic beta-receptor blockers and epinephrine on intraocular pressure and pupil size was investigated in healthy volunteers. Oral (atenolol and propranolol) and local (timolol) beta-blockers were studied. The experiment was carried out under double-blind randomized crossover conditions. The results showed that the combination of oral beta-blockers with topical epinephrine had an additive hypotensive effect on IOP, while timolol and epinephrine eyedrops both reduced the IOP used alone, but combined had an antagonistic effect, resulting in the disappearance of the epinephrine-mediated IOP reduction.

  11. Macular ischemia after intravitreal amikacin on patient with intraocular foreign body.

    PubMed

    Kartasasmita, Arief; Mona, Susi; Iskandar, Erwin; Sovani, Iwan; Panggabean, Djonggi

    2017-01-01

    Background: Although still used in third world countries, amikacin has a harmful effect to be used intravitreally. Purpose: To report macular ischemia after an intravitreal injection of amikacin Methods: A case report regarding a traumatized eye of a 26-year-old man that was injected intravitreally with amikacin due to intraocular foreign body endophthalmitis Results: Angiography and OCT show macular ischemia due to amikacin toxicity. Conclusion: The case reported here is to alert about the potential harmful effect of intravitreally injected amikacin despite its role as an accepted regimen for endohthalmitis cases.

  12. Macular ischemia after intravitreal amikacin on patient with intraocular foreign body

    PubMed Central

    Kartasasmita, Arief; Mona, Susi; Iskandar, Erwin; Sovani, Iwan; Panggabean, Djonggi

    2017-01-01

    Background: Although still used in third world countries, amikacin has a harmful effect to be used intravitreally. Purpose: To report macular ischemia after an intravitreal injection of amikacin Methods: A case report regarding a traumatized eye of a 26-year-old man that was injected intravitreally with amikacin due to intraocular foreign body endophthalmitis Results: Angiography and OCT show macular ischemia due to amikacin toxicity. Conclusion: The case reported here is to alert about the potential harmful effect of intravitreally injected amikacin despite its role as an accepted regimen for endohthalmitis cases.

  13. Ultraviolet or blue-filtering intraocular lenses: what is the evidence?

    PubMed Central

    Downes, S M

    2016-01-01

    Cataract surgery was revolutionised by the introduction of modern intraocular lenses in the late 1940's. By the late 1960's to 1970's evidence had emerged that short-wavelength light caused phototoxicity at the retina and retinal pigment epithelium. By the early 1980's ultraviolet filters had been incorporated into intraocular lenses. This caused intense controversy, as there was concern that the UV-filtering chromophore might leach out into the eye causing toxicity. With the arrival of blue-filtering intraocular lenses (BFIOLs) in 1990's, a further debate was ignited as to their safety and potential disadvantages. Selecting the optimal performing intraocular lens to obtain the best visual performance with the fewest potential drawbacks has become complex and challenging for cataract surgeons and their patients with the wide choice of lenses available. Choosing a personalised lens to address astigmatism, presbyopia, spherical aberration, chromatic aberration, and potentially to shield the retina from short-wavelength light is now possible. The potential benefits and possible side effects of these different innovations emphasise the importance of assessing the evidence for their clinical utility, allowing the surgeon and the patient to weigh-up the risk benefit ratio and make an informed decision. The BFIOLs were developed to reduce cyanopsia, address chromatic aberration, and improve contrast sensitivity in different lighting conditions, as well as to prevent short-wavelength light reaching the retina thus potentially reducing the risk of developing age-related macular degeneration. Further design development of the BFIOLs was to mimic the natural crystalline lens absorption and transmittance properties in adulthood. Multiple publications have reported on the potential benefits and pitfalls of implanting a blue-filtering lens. The potential disadvantages raised in the literature over the last 25 years since their introduction, regarding compromise of visual

  14. Paul Sullivan: catalyst in the history and use of intraocular sulfur hexafluoride.

    PubMed

    Blodi, Christopher F

    2015-01-01

    The use of air to attempt to reattach the retina dates back to 1909. However, despite the widespread use of intraocular air in the 1950s and 1960s, retinal surgeons struggled with the main limitation of the device (ie, the relatively short duration of the gas within the vitreous cavity). Fortuitous events in the late 1960s allowed Paul Sullivan, MD, to introduce the first expansile gas, sulfur hexafluoride, to Edward W.D. Norton, MD, and his colleagues at the University of Miami. The use of sulfur hexafluoride helped revolutionize retinal detachment surgery and allowed for further advances in treating other posterior segment diseases.

  15. Residual aniseikonia among patients fitted with one or two intraocular lenses (pseudophakic corrections)

    PubMed

    Lakshminarayanan, V; Enoch, J M; Knowles, R A

    1993-02-01

    In the presence of one or two intraocular lenses (IOL's; pseudophakic corrections) or in the presence of naturally occurring or developmental anisometropia (due to a tumescent cataract) some induced or residual refractive aniseikonia is usually encountered. We wish to call this problem to the attention of the optometric practitioner. We provide a discussion of the resultant aniseikonia and simple rules of thumb for management of such patients with refractive aniseikonia. Aniseikonia in these patients may be less important than once had been suggested, but certainly it is more significant than it is currently being considered. Use of personal computers to calculate this aniseikonia makes appropriate correction relatively easy and readily applicable.

  16. Placement of a crystalline lens and intraocular lens: Retinal image quality.

    PubMed

    Siedlecki, Damian; Nowak, Jerzy; Zajac, Marek

    2006-01-01

    The influence of changes of both crystalline lens and intraocular lens (IOL) misalignment on the retinal image quality was investigated. The optical model of the eye used in investigations was the Liou-Brennan model, which is commonly considered as one of the most anatomically accurate. The original crystalline lens from this model was replaced with an IOL, made of rigid polymethylmethacrylate, in a way that recommend obligatory procedures. The modifications that were made both for crystalline lens and IOL were the longitudinal, the transversal, and the angular displacement.

  17. Toxic anterior segment syndrome after foldable artiflex iris-fixated phakic intraocular lens implantation.

    PubMed

    van Philips, Lucien A M

    2011-01-01

    Toxic anterior segment syndrome (TASS) developed in four cases after uneventful implantation of a foldable iris-fixated phakic intraocular lens (pIOL). Two cases occurred sequentially in one patient. The TASS subsided without complications in all cases after intensive topical steroid treatment. A multitude of possible causes is considered for the occurrence of these TASS cases. From the sterilization and cleaning of surgical instruments to the possibility of endotoxines in ophthalmic viscosurgical devices (OVD). These rare cases should alert the surgeon to the possibility of TASS after pIOL implantation.

  18. Influence of ocular longitudinal chromatic aberration on the selection of aspheric intraocular lenses.

    PubMed

    Hong, Xin; Choi, Myoung

    2010-12-06

    Polychromatic defocus could affect the optimal residual spherical aberration that could yield the best image quality for patients with intraocular lenses (IOLs). Modulation transfer functions (MTFs) were generated using a model that included polychromatic defocus. The maximum MTF volume occurred at + 0.05 μm of overall ocular spherical aberration. For 3 case studies, the optimal overall ocular spherical aberration was ~0.05 μm more positive with the contribution of polychromatic defocus than without it. Overall, the model indicated that image quality was usually best when IOLs allowed overall ocular spherical aberration that was slightly positive, rather than strongly positive, zero, or negative.

  19. 7 CFR Exhibit G to Subpart E of... - Exhibit G to Subpart E of Part 1980

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 14 2010-01-01 2009-01-01 true Exhibit G to Subpart E of Part 1980 G Exhibit G to Subpart E of Part 1980 Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING... Program Pt. 1980, Subpt. E, Exh. G Exhibit G to Subpart E of Part 1980 Note: The Exhibit is not...

  20. System for Rapid, Precise Modulation of Intraocular Pressure, toward Minimally-Invasive In Vivo Measurement of Intracranial Pressure

    PubMed Central

    Stockslager, Max A.; Samuels, Brian C.; Allingham, R. Rand; Klesmith, Zoe A.; Schwaner, Stephen A.; Forest, Craig R.; Ethier, C. Ross

    2016-01-01

    Pathologic changes in intracranial pressure (ICP) are commonly observed in a variety of medical conditions, including traumatic brain injury, stroke, brain tumors, and glaucoma. However, current ICP measurement techniques are invasive, requiring a lumbar puncture or surgical insertion of a cannula into the cerebrospinal fluid (CSF)-filled ventricles of the brain. A potential alternative approach to ICP measurement leverages the unique anatomy of the central retinal vein, which is exposed to both intraocular pressure (IOP) and ICP as it travels inside the eye and through the optic nerve; manipulating IOP while observing changes in the natural pulsations of the central retinal vein could potentially provide an accurate, indirect measure of ICP. As a step toward implementing this technique, we describe the design, fabrication, and characterization of a system that is capable of manipulating IOP in vivo with <0.1 mmHg resolution and settling times less than 2 seconds. In vitro tests were carried out to characterize system performance. Then, as a proof of concept, we used the system to manipulate IOP in tree shrews (Tupaia belangeri) while video of the retinal vessels was recorded and the caliber of a selected vein was quantified. Modulating IOP using our system elicited a rapid change in the appearance of the retinal vein of interest: IOP was lowered from 10 to 3 mmHg, and retinal vein caliber sharply increased as IOP decreased from 7 to 5 mmHg. Another important feature of this technology is its capability to measure ocular compliance and outflow facility in vivo, as demonstrated in tree shrews. Collectively, these proof-of-concept demonstrations support the utility of this system to manipulate IOP for a variety of useful applications in ocular biomechanics, and provide a framework for further study of the mechanisms of retinal venous pulsation. PMID:26771837

  1. High-dose methotrexate following intravitreal methotrexate administration in preventing central nervous system involvement of primary intraocular lymphoma.

    PubMed

    Akiyama, Hiroki; Takase, Hiroshi; Kubo, Fumito; Miki, Tohru; Yamamoto, Masahide; Tomita, Makoto; Mochizuki, Manabu; Miura, Osamu; Arai, Ayako

    2016-10-01

    In order to prevent central nervous system (CNS) involvement and improve the prognosis of primary intraocular lymphoma (PIOL), we prospectively evaluated the efficacy of combined therapy using intravitreal methotrexate (MTX) and systemic high-dose MTX on treatment-naïve PIOL. Patients with newly diagnosed PIOL whose lymphoma was limited to the eyes were enrolled. The patients were treated with weekly intravitreal MTX until the ocular lesions were resolved, followed by five cycles of systemic high-dose MTX (3.5 g/m(2) ) every other week. Ten patients were enrolled in this study and completed the treatment. All patients achieved complete response for their ocular lesions with rapid decrease of intravitreal interleukin-10 concentration. Adverse events of intravitreal and systemic high-dose MTX were mild and tolerable. With a median follow-up of 29.5 months, four patients (40%) experienced the CNS disease development and the mean CNS lymphoma-free survival (CLFS) time was 51.1 months. Two-year CLFS, which was the primary end-point of the study, was 58.3% (95% confidence interval, 23.0-82.1%). In contrast, eight patients were treated with intravitreal MTX alone in our institute, and their 2-year CLFS was 37.5% (95% confidence interval, 8.7-67.4%). In conclusion, systemic high-dose MTX following intravitreal MTX is feasible and might be effective in preventing CNS involvement of PIOL. Further arrangements are worth considering in order to improve the effects. This study was registered with UMIN Clinical Trials Registry (UMIN000003921).

  2. Feasibility study of sustained-release travoprost punctum plug for intraocular pressure reduction in an Asian population

    PubMed Central

    Perera, Shamira A; Ting, Daniel SW; Nongpiur, Monisha E; Chew, Paul T; Aquino, Maria Cecilia D; Sng, Chelvin CA; Ho, Sue-Wei; Aung, Tin

    2016-01-01

    Purpose To investigate the efficacy and safety of a punctum plug-based sustained drug release system for a prostaglandin analog, travoprost (OTX-TP), for intraocular pressure (IOP) reduction in an Asian population. Methods This is an initial feasibility, prospective, single-arm study involving 26 eyes and a bioresorbable punctum plug containing OTX-TP. An OTX-TP was placed in the vertical portion of the superior or inferior canaliculus of patients with primary open-angle glaucoma or ocular hypertension. The main outcome measure was the IOP-lowering efficacy of OTX-TP at 3 (8 am) and 10, 20, and 30 days (8 am, 10 am, and 4 pm), compared to baseline. Results A total of 26 OTX-TP were inserted for 17 subjects. The mean (standard deviation) age was 57.2 (13.8) years. At 10 days, all plugs were still present, and the IOP reduction from baseline was 6.2 (23%), 5.4 (21%), and 7.5 mmHg (28%) at 8 am, 10 am, and 4 pm, respectively. At 10 days, the mean IOP (standard error of mean) was 21.2 (1.2), 20.4 (0.8), and 19.7 (1.0) at 8 am, 10 am, and 4 pm, respectively, showing no discernible IOP trend during the course of the day. At 30 days, plug retention had declined to 42%, and the overall IOP reduction had decreased to 16%. Conclusion The sustained-release OTX-TP is able to reduce IOP by 24% (day 10) and 15.6% (day 30), respectively. It is a potentially well-tolerable ocular hypotensive for glaucoma patients with a history of poor compliance. PMID:27175058

  3. Changes in intraocular pressure and horizontal pupil diameter during use of topical mydriatics in the canine eye

    PubMed Central

    Kovalcuka, Liga; Ilgazs, Agris; Bandere, Dace; Williams, David L.

    2017-01-01

    The objective of this study was to determine the effects of topical 0.5% tropicamide, 1% atropine sulphate and 10% phenylephrine hydrochloride ophthalmic solutions on intraocular pressure (IOP) and horizontal pupil diameter (HPD) in the dog during the first hour after treatment. Forty clinically and ophthalmologically normal canine patients (between the ages of 2 and 6 years) of varying breed and sex were used in this study. Animals were randomly divided into four groups of ten and given one drop of tropicamide, atropine, phenylephrine or saline into one eye. IOP and HPD were measured in both eyes every 5 minutes for 60 minutes. Tropicamide increased IOP by 8.8±4.0 mmHg 35 minutes post-treatment compared to pre-treatment (P<0.01) only in treated eye. IOP in the contralateral eye did not increase. With atropine the maximum increase in IOP was 2.6±2.8 mmHg at 20 minutes post treatment in the treated eye (P<0.01). IOP in the contralateral eye did not increase. Phenylephrine increased IOP by 2.3±2.1 mmHg (P<0.05) 10 minutes after treatment. Also in the untreated eye IOP increased by 2.3±2.1 mmHg, 20 minutes post-treatment. Maximum HPD in eyes treated with tropicamide occurred at 55 minutes and with atropine at 60 minutes. There were no HPD changes in the contralateral, untreated eye. Topical 10% phenylephrine showed maximal pupil dilation 60 minutes after treatment, but the HPD of the – untreated eye slightly decreased at 15 minutes, but this change only reached statistical significance at 40 min post- treatment (P<0.05). Normal saline showed no influence on IOP or HPD. The drugs investigated here show a significant increase in IOP after mydriatics. PMID:28210543

  4. Serial Multifocal Electroretinograms during Long-term Elevation and Reduction of Intraocular Pressure in Non-human Primates

    PubMed Central

    Nork, T. Michael; Kim, Charlene B. Y.; Heatley, Gregg A.; Kaufman, Paul L.; Lucarelli, Mark J.; Levin, Leonard A.; Ver Hoeve, James N.

    2010-01-01

    The purpose of this study was to evaluate the relationship between elevations of intraocular pressure (IOP) and the multifocal electroretinogram (mfERG) in non-human primates. Experimental glaucoma was induced in 4 rhesus and 4 cynomolgus monkeys by laser trabecular meshwork destruction (LTD) in one eye. To evaluate the contribution of ganglion cells to mfERG changes, one monkey of each species had previously underwent unilateral optic nerve transection (ONT). After ≥ 44 weeks of elevation, the IOP was reduced by trabeculectomy in 2 non-transected animals. In the intact (non-transected) animals there was an increase in the amplitude of the early mfERG waveforms (N1 and P1) of the first order kernel (K1) throughout the period of IOP elevation in all of the rhesus, but not all of the cynomolgus monkeys. A species difference was also present as a decrease of the second order kernel, first slice (K2.1) in all of the cynomolgus monkeys but only in 1 of the rhesus monkeys (the 1 with the ONT). Similar IOP effects on the mfERG were seen in the ONT animals. Surgical lowering of IOP resulted in a return of the elevated K1 amplitudes to baseline levels. However, the depressed K2.1 RMS in the cynomolgus monkeys did not recover. These results demonstrate species-specific changes in cone-driven retinal function during periods of elevated IOP. These IOP-related effects can occur in the absence of retinal ganglion cells and may be reversible. PMID:20422254

  5. Changes in corneal endothelium cell characteristics after cataract surgery with and without use of viscoelastic substances during intraocular lens implantation

    PubMed Central

    Schulze, Stephan D; Bertelmann, Thomas; Manojlovic, Irena; Bodanowitz, Stefan; Irle, Sebastian; Sekundo, Walter

    2015-01-01

    Purpose To evaluate whether the use of balanced salt solution (BSS) or an ophthalmic viscoelastic device (OVD) during hydrophilic acrylic intraocular lens (IOL) implantation variously impacts corneal endothelial cell characteristics in eyes undergoing uneventful phacoemulsifications. Methods Prospective nonrandomized observational clinical trial. Patients were assigned either to the BSS plus® or to the OVD Z-Celcoat™ group depending on the substance used during IOL implantation. Corneal endothelium cell characteristics were obtained before, 1 week, and 6 weeks after surgery. Intraoperative parameters (eg, surgery time, phacoemulsification energy) were recorded. Results Ninety-seven eyes were assigned to the BSS plus and 86 eyes to the Z-Celcoat group. Preoperative corneal endothelium cell density (ECD) and endothelium cell size were 2,506±310 cells/mm2/2,433±261 cells/mm2 and 406±47 µm2/416±50 µm2 (P=0.107/P=0.09). After 1 and 6 weeks, ECD decreased and endothelium cell size increased significantly in both groups (each P<0.001) without significant differences between both groups (each P>0.05). Irrigation–aspiration suction time (30.3±16.6 versus 36.3±14.5 seconds) and overall surgical time (7.2±1.2 versus 8.0±1.4 minutes) were significantly longer in the OVD Z-Celcoat group (each P<0.001). No complications or serious side effects occurred. Conclusion Implantation of a hydrophilic acrylic IOL under BSS infusion seems to be a useful and faster alternative in experienced hands without generating higher ECD loss rates. PMID:26609218

  6. Characterization of intraocular pressure pattern and changes of retinal ganglion cells in DBA2J glaucoma mice

    PubMed Central

    Wang, Jing; Dong, Yu

    2016-01-01

    AIM To characterize the pattern of intraocular pressure (IOP) change and the deficit of retinal ganglion cells (RGCs) in DBA2J, which is most well-characterized chronic glaucoma mouse model and wild type (WT) C57bl/6 mice, and to study the relationship between IOP change and RGCs deficit. METHODS IOP was monitored with a rebound tonometer in WT C57bl/6 and DBA2J mice from 3 to 15-month-old. Retinal function was evaluated by dark-adapted electroretinogram (ERG) in DBA2J and WT mice of 15-month-old. A dye (Neurobiotin) was applied to optic nerve stump to retrograde label RGCs. TO-PRO-3 visualized all nuclei of cells in the RGC layer. RESULTS The IOP in WT mice was 9.03±0.6 mm Hg on average and did not increase significantly as aging. The IOP in DBA2J mice, arranging from 7.2 to 28 mm Hg, was increasing significantly as aging, and it was normal at 3-month-old compared with WT mice, slightly increased from 7-month-old and increased in 50% animals at 11-month-old and in 38% animals at 15-month-old. The RGCs density in DBA2J mice started reducing by 7-month-old, continuously decreased until reached about 20% of RGC in WT retina by 15-month-old. RGC density was not linearly correlated with IOP in 15-month-old DBA2J mice. The amplitude of positive scotopic threshold response, and negative scotopic threshold response of ERG were significantly reduced in DBA2J mice of 15-month-old than that in age-paired WT mice. CONCLUSION The present study found that DBA2J mice display pathological and functional deficits of the retina that was not linearly correlated with IOP. PMID:26949637

  7. Lens Position Parameters as Predictors of Intraocular Pressure Reduction After Cataract Surgery in Nonglaucomatous Patients With Open Angles

    PubMed Central

    Hsu, Chi-Hsin; Kakigi, Caitlin L.; Lin, Shuai-Chun; Wang, Yuan-Hung; Porco, Travis; Lin, Shan C.

    2015-01-01

    Purpose To evaluate the relationship between lens position parameters and intraocular pressure (IOP) reduction after cataract surgery in nonglaucomatous eyes with open angles. Methods The main outcome of the prospective study was percentage of IOP change, which was calculated using the preoperative IOP and the IOP 4 months after cataract surgery in nonglaucomatous eyes with open angles. Lens position (LP), defined as anterior chamber depth (ACD) + 1/2 lens thickness (LT), was assessed preoperatively using parameters from optical biometry. Preoperative IOP, central corneal thickness, ACD, LT, axial length (AXL), and the ratio of preoperative IOP to ACD (PD ratio) were also evaluated as potential predictors of percentage of IOP change. The predictive values of the parameters we found to be associated with the primary outcome were compared. Results Four months after cataract surgery, the average IOP reduction was 2.03 ± 2.42 mm Hg, a 12.74% reduction from the preoperative mean of 14.5 ± 3.05 mm Hg. Lens position was correlated with IOP reduction percentage after adjusting for confounders (P = 0.002). Higher preoperative IOP, shallower ACD, shorter AXL, and thicker LT were significantly associated with percentage of IOP decrease. Although not statistically significant, LP was a better predictor of percentage of IOP change compared to PD ratio, preoperative IOP, and ACD. Conclusions The percentage of IOP reduction after cataract surgery in nonglaucomatous eyes with open angles is greater in more anteriorly positioned lenses. Lens position, which is convenient to compute by basic ocular biometric data, is an accessible predictor with considerable predictive value for postoperative IOP change. PMID:26650901

  8. 43 CFR 4.824 - Exhibits.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Procedural Rules Applicable to Practice and Procedure for Hearings, Decisions, and Administrative Review... Interior-Effectuation of Title VI of the Civil Rights Act of 1964 Procedures § 4.824 Exhibits....

  9. 18 CFR 32.2 - Required exhibits.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... of operating such facilities. Exhibit B. A general or key map on a scale not greater than 20 miles to... facilities used for the generation and transmission of electric energy, indicating on said map the...

  10. The Making of a Museum Exhibition.

    ERIC Educational Resources Information Center

    Bleecker, Samuel E.

    1979-01-01

    Discusses the preparation of the Reptile and Amphibian exhibition at the American Museum of Natural History. Various steps involved in developing the ten showcases in a six-year period are presented. (SA)

  11. 18 CFR 153.8 - Required exhibits.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) Exhibit D. If the proposal is for a pipeline interconnection to import or export natural gas, a copy of... authority, that will issue each required authorization; the date each request for authorization...

  12. Detrimental effects of cigarette smoke constituents on physiological development of extraocular and intraocular structures.

    PubMed

    Ejaz, Sohail; Adil, Muhammad; Oh, Myong Ho; Anjum, Syed Muhammad Muneeb; Ashraf, Muhammad; Lim, Chae Woong

    2009-08-01

    No investigation has yet been accomplished to screen the detrimental effects of cigarette smoke condensate (CSC) and total particular matter solution (TPMS) on embryonic development of extraocular and intraocular structures. In this report, chicken embryo assay was utilized to undermine diverse ocular pathologies produced by exposure of CSC and TPM. Extraocular anomalies triggered after exposure of CSC and TPMS include degeneration of optic chiasma, medial rectus muscle, and inflammatory lesions in forebrain. Histological investigations of CSC and TPMS-treated embryos also exposed delayed differentiation of photoreceptor layer, degeneration of retinal ganglion and nerve cell layer. In addition, corneal thickness, deterioration and complete loss of hyaloid vasculature were observed. Extraocular and intraocular regions of TPMS-treated embryos also revealed widespread hemorrhages in the entire cephalic, optic disc, ganglion cell layer and vitreous humor area. The findings of our experiment demonstrate, for the first time, that exposure to CSC and TPMS is hazardous for developing embryos and it has potential detrimental effects on several underlying events of ocular development. Moreover, it was also intriguing that toxicity profile of TMP was much more higher than CSC with more profound detrimental effects on ocular development.

  13. Comparison of pseudophakic retinal straylight in spherical/aspherical and hydrophobic/hydrophilic intraocular lens

    PubMed Central

    Tang, Yong; Song, Hui; Chen, Jing; Tang, Xin

    2015-01-01

    AIM To study the potential reasons of increased straylight in pseudophakic eyes. METHODS Cross-sectional study. Seventy patients diagnosed as bilateral age-related cataract and implanted with Tecnis ZA9003, Sensar AR40e, SA60AT, XLSTABI ZO or Akeros AO intraocular lens (IOL) were enrolled in this research. Straylight was measured by a C-Quant straylight meter three to four weeks postoperatively. Five different modalities of IOL, including spherical/aspherical optics and hydrophobic/hydrophilic material were tested in this study. Normal as well as dilated pupils were used. The main outcome variable for straylight measurement was the logarithmic straylight parameter, log(s). RESULTS The straylight parameter increased significantly after pupil dilation (P<0.05). Straylight of aspherical IOL was significantly higher after pupil dilation (P<0.05) compared to spherical IOL. In normal pupil, straylight of hydrophobic IOL was significant higher when compared with hydrophilic IOL (P<0.05). CONCLUSION Straylight and visual acuity stand for the different aspects of visual function. Several factors including pupil diameter, optic material, aspherical design of IOL influence intraocular light scattering in pseudophakic eyes. Further investigation was needed to study the impact of optic material and optic surface design on pseudophakic straylight. PMID:26682163

  14. Opacification of hydrophilic intraocular lenses after Descemet stripping automated endothelial keratoplasty

    PubMed Central

    Morgan-Warren, Peter J; Andreatta, Walter; Patel, Amit K

    2015-01-01

    Purpose Opacification of hydrophilic acrylic intraocular lenses (IOLs) is an emerging complication following Descemet stripping automated endothelial keratoplasty (DSAEK). We report six cases and review the current literature. Methods In this retrospective, noncomparative, observational case series, patients with IOL opacification after previous DSAEK surgery were identified from corneal clinic records. Case notes were reviewed for demographic details, indication for DSAEK, IOL model, incidence of rebubbling, and postoperative course. Results Six patients developed IOL opacification after DSAEK. All patients had Fuchs’ endothelial dystrophy and had previously received hydrophilic acrylic IOL models. Central anterior IOL opacification was noted in all six cases. Five cases (83%) had required rebubbling due to dislocated graft tissue, and one had an early postoperative intraocular pressure (IOP) rise. Five cases (83%) were managed conservatively, and one case with a failed graft underwent redo DSAEK and IOL exchange. Conclusion Repeated exposure to intracameral air, raised IOP, and other patient influences may be major etiological factors for IOL opacification after DSAEK. We advise avoiding hydrophilic acrylic IOL models in patients who may require future endothelial keratoplasty. PMID:25709389

  15. Retropupillary iris-claw intraocular lens for the surgical correction of aphakia in cases with microspherophakia

    PubMed Central

    Fouda, Sameh Mosaad; Al Aswad, Mahmoud A; Ibrahim, Basem M; Bori, Ashraf; Mattout, Hala K

    2016-01-01

    Purpose: This study aimed to evaluate the safety and efficacy of retropupillary fixation of an iris-claw intraocular lens (IOL; Verisyse polymethyl methacrylate IOL, Abbott Medical Optics [AMO], Netherlands) for the surgical correction of aphakia in microspherophakic eyes without sufficient capsular support. Design: This was a prospective, interventional, noncomparative case series. Methods: This interventional case series comprised 17 eyes of 9 microspherophakic patients. Retropupillary fixation of the Verisyse iris-claw IOL (AMO) was performed in all cases. The surgical time was measured. Corrected distance visual acuity, astigmatism, intraocular pressure (IOP), tissue reaction, pigment dispersion, and stability of the IOL were studied 1 day, 3 days, 1 week, 2 weeks, 1 month, and 6 months postoperatively. Results: Eight patients had familial microspherophakia and one patient had Marfan's syndrome. Eighty-two percent of the cases achieved a visual acuity of 0.3 or better. There was no significant postoperative inflammatory reaction. Transient elevation of IOP was recorded in two cases in the 1st week only. One IOL developed disengagement of one of the haptics from the iris and was successfully re-engaged. All the other IOLs were well centered and stable. The mean surgical time was 18.0 ± 4.5 min. Conclusions: Retropupillary fixation of an iris-claw IOL is a safe and effective procedure that provides early visual recovery. It is also a time-saving method for correcting aphakia in microspherophakic eyes without sufficient capsular support. PMID:28112127

  16. Solid Lipid Nanoparticles Improve the Diclofenac Availability in Vitreous after Intraocular Injection

    PubMed Central

    Abrishami, Majid; Vakili Ahrari Roodi, Mohammad

    2016-01-01

    Purpose. In order to improve the drug availability after intravitreal administration, solid lipid nanoparticles (SLNs) containing diclofenac were prepared. Methods. In this experimental study, 18 albino rabbits were included. In right and left eyes of all rabbits, SLNs containing diclofenac and commercial form of diclofenac (0.3 mg drug) were intravitreally injected, respectively. One, four, twelve, twenty-four, and forty-eight hours after injection, vitreous and aqueous humor samples were obtained in all cases. Then, the concentration of diclofenac sodium was evaluated in all samples. Results. Size of nanoparticles was around 170 nm after preparation. Drug concentration in eyes injected with SLNs was significantly higher than left eyes injected with commercial formulation up to 4 hours after intravitreal injection (p < 0.05). Diclofenac was quantified in samples up to 48 hours after intraocular injection. Four hours after intravitreal injection, the concentration of diclofenac in vitreous and aqueous humor of eyes receiving SLNs was, respectively, 2.5 and 6.5 times higher than eyes injected with commercial form of drug. Conclusions. Here, we demonstrate the potential of SLNs as a carrier of diclofenac for intraocular injection in order to prevent the systemic effects of the drug, increase the injection intervals, and improve the patient compliance. PMID:27803815

  17. Study on intra-ocular lens aberration measurement in-air

    NASA Astrophysics Data System (ADS)

    Wang, Yuanyuan; Chen, Jiaojie; Fen, Haihua; Hu, Chuan; Li, Yiyi

    2010-10-01

    In clinical ophthalmology, the wavefront aberration of human eyes is expressed by Zernike polynomial after cataract surgery and intraocular lens implantation, the human eyes aberration will change. The problem of objective evaluation of wavefront aberration introduced by the Intra-ocular (IOL) in-vivo remains unsolved. This paper introduced the measurement principal of IOL wavefront aberration with expression by Zernike polynominal in air. A Hartmann-Shack wavefront sensor system was constructed to measure the wavefront of IOL and to get the corresponding grid patterns. After a series of computer image processing steps, 7th order with 35 items Zernike coefficients was obtained. The IOL of 20.0D power was measured 5 times by this system to get the spherical aberration about 6.73+/-0.02μm, demonstrating the good repeatability of the system. Ten IOLs with the same 20.0D power but difference in surface curvature were chosen for measurement. The spherical aberration observed were in the range of 2.74μm-11.26μm. These results are valuable for the optical design of IOLs and the aberration analysis of human eyes post-operation.

  18. Laser flare photometry: a noninvasive, objective, and quantitative method to measure intraocular inflammation.

    PubMed

    Tugal-Tutkun, Ilknur; Herbort, Carl P

    2010-10-01

    Aqueous flare and cells are the two inflammatory parameters of anterior chamber inflammation resulting from disruption of the blood-ocular barriers. When examined with the slit lamp, measurement of intraocular inflammation remains subjective with considerable intra- and interobserver variations. Laser flare cell photometry is an objective quantitative method that enables accurate measurement of these parameters with very high reproducibility. Laser flare photometry allows detection of subclinical alterations in the blood-ocular barriers, identifying subtle pathological changes that could not have been recorded otherwise. With the use of this method, it has been possible to compare the effect of different surgical techniques, surgical adjuncts, and anti-inflammatory medications on intraocular inflammation. Clinical studies of uveitis patients have shown that flare measurements by laser flare photometry allowed precise monitoring of well-defined uveitic entities and prediction of disease relapse. Relationships of laser flare photometry values with complications of uveitis and visual loss further indicate that flare measurement by laser flare photometry should be included in the routine follow-up of patients with uveitis.

  19. Incidence of Intraocular Pressure Elevation following Intravitreal Ranibizumab (Lucentis) for Age-related Macular Degeneration

    PubMed Central

    Reis, Gustavo MSM; Grigg, John; Chua, Brian; Lee, Anne; Lim, Ridia; Higgins, Ralph; Martins, Alessandra; Goldberg, Ivan

    2017-01-01

    ABSTRACT Aim The aim of this article is to evaluate the rate of patients developing sustained elevated intraocular pressure (IOP) after ranibizumab (Lucentis) intravitreal (IVT) injections. Design This is a retrospective study. Participants Charts of 192 consecutive patients receiving Lucentis for age-related macular degeneration (AMD) were retrospectively reviewed. Materials and methods We enrolled patients with at least two IOP measurements between injections. Elevated IOP was defined as >21 mm Hg with an increase of at least 20% from baseline. Noninjected contralateral eyes of the same patient cohort were used as control. Main outcome measures Primary outcome was defined as elevated IOP. Secondary outcomes were presence and type of glaucoma, number of injections, and time to IOP elevation. Results Elevated IOP occurred at a significantly higher rate in eyes receiving IVT ranibizumab (7.47%; n = 9) compared with control (0.93%; n = 1). Patients with preexisting glaucoma or ocular hypertension (OHT) were more likely to develop elevated IOP after IVT ranibizumab injection. Conclusion Intravitreal ranibizumab injections are associated with sustained IOP elevation in some eyes. How to cite this article Reis GMSM, Grigg J, Chua B, Lee A, Lim R, Higgins R, Martins A, Goldberg I, Clement CI. The Incidence of Intraocular Pressure Elevation following Intravitreal Ranibizumab (Lucentis) for Age-related Macular Degeneration. J Curr Glaucoma Pract 2017;11(1):3-7. PMID:28138211

  20. The effect of anaesthesia on the intraocular volume of the C3F8 gas bubble.

    PubMed

    Briggs, M; Wong, D; Groenewald, C; McGalliard, J; Kelly, J; Harper, J

    1997-01-01

    Long-acting intraocular gas bubbles are frequently used during vitrectomy to tamponade retinal breaks. The aim of this study was to determine the effect of nitrous oxide anaesthesia on the size and effectiveness of the post-vitrectomy gas bubble. Twenty vitrectomy procedures with injection of 12% perfluoropropane (C3F8) gas were performed. For 10 of the cases routine anaesthesia with nitrous oxide was used and for 10 cases non-nitrous anaesthesia with propofol was used. The volume of the intraocular gas bubble was estimated 24 hours post-operatively using A-scan biometry. At 24 hours the gas bubble occupied a mean of 65.1% of the eye in anaesthesia with nitrous oxide and a mean of 66.1% in anaesthesia with intravenous propofol. The wide range of values of gas-fill recorded at 24 hours makes comparison of the two groups inappropriate. Several factors may account for this spread of values, but in our opinion it is the uncontrolled leakage from the sclerostomies which is the most likely. This study suggests that anaesthesia using nitrous oxide does not adversely affect the size of the C3F8 gas bubble at 24 hours post-vitrectomy when compared with anaesthesia without nitrous oxide.

  1. Hydrophilic Acrylic Intraocular Lens Opacification after Descemet Stripping Automated Endothelial Keratoplasty

    PubMed Central

    Norouzpour, Amir; Zarei-Ghanavati, Siamak

    2016-01-01

    Purpose: To report hydrophilic acylic intraocular lens (IOL) opacification after Descemet Stripping Automated Endothelial Keratoplasty (DSAEK) in an eye with multiple prior intraocular surgeries and iatrogenic aniridia. Case Report: A 34-year-old woman with history of penetrating keratoplasty (PKP) for advanced keratoconus and subsequent Urrets-Zavalia Syndrome (UZS) underwent phacoemulsification and hydrophilic acrylic IOL implantation for her cataract. In order to control post-PKP glaucoma, multiple glaucoma surgeries including two glaucoma drainage implants were performed. As the original corneal graft failed, the patient subsequently underwent re-PKP. Four years later, she underwent DSAEK for treatment of the second graft failure. Ten months after DSAEK, a double semi-circular pattern of IOL opacification was observed on the anterior surface of the IOL. The patient did not report any complaints and we decided not to exchange the IOL. Conclusion: In an eye with UZS and iatrogenic aniridia, IOL opacification may result from direct contact between the IOL surface and exogenous air. Aniridia can be a risk factor for development of IOL opacification after DSAEK. Further studies are required to confirm this hypothesis. PMID:27413506

  2. Piggy back intraocular lens for the correction of buckling surgery-induced refractive error in pseudophakia.

    PubMed

    Sinha, Rajesh; Singh, Reena; Sharma, Vijay K; Titiyal, Jeewan S

    2016-12-30

    A 29-year-old man presented to us with bilateral pseudophakia with suboptimal vision in right eye. His uncorrected distance visual acuity (UDVA) on Snellen's chart was 6/36 and 6/9 in right eye (OD) and left eye (OS), respectively. It improved to 6/9 OD with -5.00DS/-0.50DC at 90° and 6/6 OS with -0.5DC at 100°. He had undergone buckling surgery 1 year back for rhegmatogenous retinal detachment in right eye and subsequently developed a myopic refractive error. A spherical piggyback intraocular lens (IOL; Rayner Sulcoflex, East Sussex) was implanted in the sulcus for refractive correction. The postoperative UDVA at 4 weeks was 6/6p. The intraocular pressure was normal and there was no significant endothelial cell loss. Piggyback IOLs can be an effective tool to correct the induced refractive error due to an increase in axial length following buckling surgery.

  3. Effects of pretreatment with mydriatics on intraocular penetration of 0.1% pranoprofen.

    PubMed

    Ogawa, T; Ohara, K; Shimizu, H

    1993-01-01

    The mechanism by which an increase in the intraocular concentration of topically applied 0.1% pranoprofen (PPF) is induced by pretreatment with Mydrin P (0.5% tropicamide and 0.5% phenylephrine) was studied in rabbit eyes. In separate experiments, solutions of each of the various ingredients contained in Mydrin P ophthalmic solution were applied 60 minutes prior to instillation of PPF. Ninety minutes after PPF instillation, its concentration in the cornea, aqueous humor and iris-ciliary body were measured by high performance liquid chromatography. PPF concentration was not increased by pretreatment with benzalkonium chloride, chlorobutanol or tropicamide, but was increased by pretreatment with phenylephrine (PHE). After the latter, the PPF concentration was 2 to 3 times higher than that obtained without Mydrin P. It is noteworthy that the concentration of PHE in the aqueous humor also was found to be increased about 3 times in the presence of PPF. The lipophilicity of PPF, judged by the octanol/buffer partition coefficient, was increased when mixed with PHE. These findings indicate that the increase in intraocular PPF concentration after pretreatment with Mydrin P was caused by PHE. This may be attributable to the enhancement of corneal permeability to PPF resulting from formation of an ion-pair complex between the anionic PPF and the cationic PHE.

  4. Influence of the Hypothalamic Arcuate Nucleus on Intraocular Pressure and the Role of Opioid Peptides

    PubMed Central

    Jin, Ji; Xu, Guo-xu; Yuan, Zhi-lan

    2014-01-01

    Background An opioid peptide neuron/humoral feedback regulation might be involved in changes of intraocular pressure (IOP). The aims of this study are to investigate the effects of arcuate nucleus (ARC) and opioid peptides on intraocular pressure (IOP). Methods Fifty-four healthy purebred New Zealand white rabbits (108eyes) were randomly divided into 4 groups, including control group, electrical stimulation group, [D-Ala2, N-Me-Phe4, Gly5-ol]-enkephalin (DAMGO) group, and [D-Pen 2, D-Pen5]- enkephalin (DPDPE) group. Bilateral IOP was measured after unilateral electrical stimulation of the ARC or unilateral microinjection into the ARC of the selective μ-opioid receptor agonist DAMGO or the selective δ opioid receptor agonist DPDPE, both alone and after pre-administration of either the non-selective opioid receptor antagonist naloxone or saline. Results Both electrical stimulation in ARC and micro-injection either or opioid receptor agonists, DAMGO or DPDPE, respectively, caused a significant bilateral reduction in IOP (P<0.05) which was more pronounced in the ipsilateral than in the contralateral eye. Pretreatment with naloxone prevented some, but not all IOP reductions. Conclusion The ARC takes part in the negative regulation of IOP, an action that may involve opioid neurons. PMID:24691128

  5. Aniseikonia for near vision with unilateral aphakia corrected by intraocular lenses.

    PubMed

    Ivashina, A I

    1981-11-01

    1. Our methods for calculation of aniseikonia for near vision allow one to determine it in every patient with an intraocular lens. 2. With an eye with an artificial lens there is a correlation between the amount of accommodation used by the phakic eye and aniseikonia changes subject to the distance from the object. Calculations for aniseikonia for near vision in 43 patients showed that with accommodation used by the normal eye aniseikonia was increased by 3.0% to 7.8% as compared with aniseikonia for distance. With accommodation of the phakic eye lacking, aniseikonia for near vision did not differ much from its value for distance. 3. Calculations for aniseikonia for near vision showed the advantage of intraocular lens implantation for obtaining iso-iconia for distance or tolerable aniseikonia not more than 2.5% to 3.0%. 4. For obtaining iso-iconia for near vision it is necessary to correct the phakic eye to switch off its accommodation partially or completely (with emmetropia, correction +2.0D for near vision).

  6. A Case of Intraocular Erosion and Intrusion by an Arruga Suture

    PubMed Central

    Kitagaki, Takakuni; Morishita, Seita; Kohmoto, Ryohsuke; Fukumoto, Masanori; Suzuki, Hiroyuki; Sato, Takaki; Kobayashi, Takatoshi; Kida, Teruyo; Nakajima, Masayuki; Ikeda, Tsunehiko

    2016-01-01

    Purpose To report a case of intraocular erosion and intrusion by an Arruga suture. Case Report This study involved a 62-year-old male who had undergone scleral buckling surgery 40 or more years ago at another hospital for rhegmatogenous retinal detachment, as well as trabeculectomy 20 years ago for primary open-angle glaucoma, in his left eye at the same hospital. However, he recently became aware of blurred vision in that eye. Upon examination, iritis was observed in the anterior portion of his left eye, as well as a great number of pigment cell keratoprecipitates on the posterior surface of the cornea. In the ocular fundus, extensive atrophy of the retinal pigment epithelium and partial hyperpigmentation was observed, accompanied by subretinal strands, yet the retina remained attached. Around the entire peripheral area of the retina we observed a ring-shaped protrusion, but we also saw a shiny, filamentous material in the vitreous cavity that penetrated the sclera and choroid, completely extending from the 4- to 8-o'clock position of the scleral buckle protrusion. To treat the iritis in the patient's left eye, we began to administrate low-concentration steroid eye drops, after which the inflammation disappeared. Conclusion In this study, we experienced a case of intraocular erosion and intrusion by an Arruga suture, and opted to treat the patient with steroid eye drops and conservative follow-up observations unless retinal redetachment and/or vitreous hemorrhage occurs. PMID:27099609

  7. Femtosecond And Picosecond Laser Ablation Of Intraocular Lenses: An Advanced Technique For Their Surface Modification

    NASA Astrophysics Data System (ADS)

    Serafetinides, A. A.; Makropoulou, M.; Spyratou, E.; Bacharis, C.; Barberoglou, M.; Englezis, A.; Kalpouzos, C.; Loukakos, P.; Pouli, P.

    2011-09-01

    Ophthalmology is entering a very interesting period with new diffractive multifocals, improved refractive multifocals, and accommodative lenses, all coming out at the same time. A new diffractive-refractive design for providing intermediated vision is apodization. In an apodized pattern, physical diffractive step heights are reduced in height, in an almost continuously varying manner. This study is aimed to investigate the use of ultrashort laser pulses to ablate the surface of intraocular lenses, and thus provide an alternative to conventional techniques. Ablation experiments were performed on hydrophilic and hydrophobic intraocular lenses (IOLs). The samples were irradiated with a Ti:Sapphire laser at λ = 0.785 μm, pulse duration 150 fs, repetition rate 1 kHz and with a Nd:YAG 4ω laser at λ = 0.266 μm, pulse duration 155 ps, repetition rate 10 Hz. We investigated the ablation efficiency and the surface modification with a Scanning Electron Microscope (SEM). The experimental results and the theoretical assumptions on the relevant ablation mechanism are discussed.

  8. High speed small gauge anterior vitrectomy cutter for scleral fixated intraocular lens implantation

    PubMed Central

    Liang, Yuan Bo; Fong, Yoly Y.Y.; Cheng, Lulu L.; Young, Alvin L.

    2017-01-01

    AIM To report the outcomes of anterior vitrectomy using high speed cutter for scleral fixated intraocular lens (SFIOL) implantation in patients with posterior capsular rupture. METHODS Medical records of 51 patients with posterior capsular rupture who received high speed cutter anterior vitrectomy via limbal incision with SFIOL implantation from June 2011 to December 2013 were reviewed retrospectively for visual outcomes and complications. RESULTS Totally 51 eyes of 51 patients were identified (23 males and 28 females). Mean age at surgery was 67.2±15y (range 27-91y), with mean follow-up of 23±8.2mo (range 12-40mo). The 49 (96.1%) eyes had improvement or unchanged of final postoperative visual acuity. The most common complication was vitreous haemorrhage (5.9%) and transient rise in intraocular pressure (5.9%) which all spontaneously resolved CONCLUSION High speed cutter anterior vitrectomy via limbal incision is a safe and effective method for those with posterior capsular rupture for SFIOL implantation. PMID:28149781

  9. Design and evaluation of an intraocular B-scan OCT-guided 36-gauge needle

    NASA Astrophysics Data System (ADS)

    Shen, Jin H.; Joos, Karen M.

    2015-03-01

    Optical coherence tomography imaging is widely used in ophthalmology and optometry clinics for diagnosing retinal disorders. External microscope-mounted OCT operating room systems have imaged retinal changes immediately following surgical manipulations. However, the goal is to image critical surgical maneuvers in real time. External microscope-mounted OCT systems have some limitations with problems tracking constantly moving intraocular surgical instruments, and formation of absolute shadows by the metallic surgical instruments upon the underlying tissues of interest. An intraocular OCT-imaging probe was developed to resolve these problems. A disposable 25-gauge probe tip extended beyond the handpiece, with a 36-gauge needle welded to a disposable tip with its end extending an additional 3.5 mm. A sealed 0.35 mm diameter GRIN lens protected the fiber scanner and focused the scanning beam at a 3 to 4 mm distance. The OCT engine was a very high-resolution spectral-domain optical coherence tomography (SDOCT) system (870 nm, Bioptigen, Inc. Durham, NC) which produced 2000 A-scan lines per B-scan image at a frequency of 5 Hz with the fiber optic oscillations matched to this frequency. Real-time imaging of the needle tip as it touched infrared paper was performed. The B-scan OCT-needle was capable of real-time performance and imaging of the phantom material. In the future, the B-scan OCT-guided needle will be used to perform sub-retinal injections.

  10. Use of intraocular lenses in children with traumatic cataract in south India

    PubMed Central

    Eckstein, M.; Vijayalakshmi, P; Killedar, M.; Gilbert, C.; Foster, A.

    1998-01-01

    AIMS—To assess the long term results of intraocular lens (IOL) implantation for traumatic cataract in young children in a developing country.
METHODS—Prospective hospital based study of 52 children (age 2-10 years) undergoing unilateral cataract extraction and IOL insertion for traumatic cataract performed by a single surgeon in south India. Children were reviewed regularly and followed up initially for 3 years.
RESULTS—There were no serious operative complications. Clinically significant posterior capsule opacification was almost universal (92%) and YAG capsulotomy or membranectomy was performed on 48 eyes. Some degree of pupil capture affected 35% of eyes and was complete in 6%. Visual acuity was 6/12 or better in 67% of eyes at the last follow up examination.
CONCLUSION—The visual acuity results 3 years after implantation of posterior chamber IOLs in older children with traumatic cataracts in south India were encouraging. In developing countries where follow up is unreliable it is essential to plan to clear the axial part of the posterior capsule either at the time of surgery or soon afterwards.

 Keywords: intraocular lens; children; cataract; India PMID:9828776

  11. Communicating Complex Sciences by Means of Exhibitions

    NASA Astrophysics Data System (ADS)

    Schneider, S.

    2011-12-01

    Earth Sciences will have to take over the leading role in global sustainable policy and in discussions about climate change. Efforts to raise attention within the politically responsible communities as well as in the public are getting more and more support by executive and advisory boards all over the world. But how can you successfully communicate complex sciences? For example, to start communication about climate change, the first step is to encourage people to be concerned about climate change. After that, one has to start thinking about how to present data and how to include the presented data into an unprejudiced context. Therefore, the communication toolbox offers various methods to reach diverse audiences. The R&D programme GEOTECHNOLOGIEN conducts roving exhibitions as one of its most successful communication tools. With roving exhibitions GEOTECHNOLOGIEN is able to get in touch with different audiences at once. The main purpose and theme of these exhibitions is to convey the everyday means of climate change to the visitors. It is within the responsibility of science to communicate the effects of a phenomenon like climate change as well as the impact of research results to the everyday life of people. Currently, a GEOTECHNOLOGIEN roving exhibition on remote sensing with satellites deals with various issues of environmental research, including a chapter on climate change. By following the 3M-concept (Meaning - Memorable - Moving), exhibitions allow to connect the visitors daily environment and personal experiences with the presented issues and objects. Therefore, hands-on exhibits, exciting multimedia effects and high-tech artefacts have to be combined with interpretive text elements to highlight the daily significance of the scientific topics and the exhibition theme respectively. To create such an exhibition, strong conceptual planning has to be conducted. This includes the specification of stern financial as well as time wise milestones. In addition

  12. When Do Children Exhibit a "Yes" Bias?

    ERIC Educational Resources Information Center

    Okanda, Mako; Itakura, Shoji

    2010-01-01

    This study investigated whether one hundred and thirty-five 3- to 6-year-old children exhibit a yes bias to various yes-no questions and whether their knowledge status affects the production of a yes bias. Three-year-olds exhibited a yes bias to all yes-no questions such as "preference-object" and "knowledge-object" questions pertaining to…

  13. Reaching the Public through Traveling Exhibitions

    NASA Astrophysics Data System (ADS)

    Dusenbery, P. B.; Harold, J. B.; Morrow, C. A.

    2004-11-01

    The Space Science Institute (SSI) of Boulder, Colorado has recently developed two museum exhibits called Alien Earths and MarsQuest. It has just started to develop another exhibit called Giant Planets. These exhibitions provide research scientists the opportunity to engage in a number of activities that are vital to the success of these major outreach programs. Alien Earths was developed in partnership with various research missions. The focus of the presentation will be on MarsQuest and Giant Planets. MarsQuest is a 5000 square-foot, \\$3M, traveling exhibition that is now touring the country. The exhibit's second 3-year tour will enable millions of Americans to share in the excitement of the scientific exploration of Mars and learn more about their own planet in the process. The associated planetarium show and education program will also be described, with particular emphasis on workshops to orient museum staff (e.g. museum educators and docents) and workshops for master educators near host museums and science centers. The workshops make innovative connections between the exhibition's interactive experiences and lesson plans aligned with the National Science Education Standards. These exhibit programs are good models for actively involving scientists and their discoveries to help improve informal science education in the museum community and for forging a stronger connection between formal and informal education. The presentation will also discuss how Giant Planets, a proposed 3500 square-foot traveling exhibition on the mysteries and discoveries of the outer planets, will be able to take advantage of the connections and resources that have been developed by the MarsQuest project.

  14. An Astrobiology Microbes Exhibit and Education Module

    NASA Technical Reports Server (NTRS)

    Lindstrom, Marilyn M.; Allen, Jaclyn S.; Stocco, Karen; Tobola, Kay; Olendzenski, Lorraine

    2001-01-01

    Telling the story of NASA-sponsored scientific research to the public in exhibits is best done by partnerships of scientists and museum professionals. Likewise, preparing classroom activities and training teachers to use them should be done by teams of teachers and scientists. Here we describe how we used such partnerships to develop a new astrobiology augmentation to the Microbes! traveling exhibit and a companion education module. "Additional information is contained in the original extended abstract."

  15. Sex differences in science museum exhibit attraction

    NASA Astrophysics Data System (ADS)

    Arámbula Greenfield, Teresa

    This study examines the relative attraction of hands-on, interactive science museum exhibits for females and males. Studies have demonstrated that such exhibits can be effective learning experiences for children, with both academic and affective benefits. Other studies have shown that girls and boys do not always experience the same science-related educational opportunities and that, even when they do, they do not necessarily receive the same benefits from them. These early differences can lead to more serious educational and professional disparities later in life. As interactive museum exhibits represent a science experience that is-readily available to both girls and boys, the question arose as to whether they were being used similarly by the two groups as well as by adult women and men. It was found that both girls and boys used all types of exhibits, but that girls were more likely than boys to use puzzles and exhibits focusing on the human body; boys were more likely than girls to use computers and exhibits illustrating physical science principles. However, this was less true of children accompanied by adults (parents) than it was of unaccompanied children on school field trips who roamed the museum more freely.Received: 16 February 1994; Revised: 3 February 1995;

  16. Using Comparative Planetology in Exhibit Development

    NASA Astrophysics Data System (ADS)

    Dusenbery, P. B.; Harold, J. B.; Morrow, C. A.

    2004-12-01

    It is critically important for the public to better understand the scientific process. Museum exhibitions are an important part of informal science education that can effectively reach public audiences as well as school groups. They provide an important gateway for the public to learn about compelling scientific endeavors. The Space Science Institute (SSI) is a national leader in producing traveling science exhibitions and their associated educational programming (i.e. interactive websites, educator workshops, public talks, instructional materials). The focus of this presentation will be on three of its exhibit projects: MarsQuest (currently on tour), Alien Earths (in fabrication), and Giant Planets (in development). MarsQuest is enabling millions of Americans to share in the excitement of the scientific exploration of Mars and to learn more about their own planet in the process. Alien Earths will bring origins-related research and discoveries to students and the American public. It has four interrelated exhibit areas: Our Place in Space, Star Birth, PlanetQuest, and Search for Life. Exhibit visitors will explore the awesome events surrounding the birth of stars and planets; they will join scientists in the hunt for planets outside our solar system including those that may be in "habitable zones" around other stars; and finally they will be able to learn about how scientists are looking for signs of life beyond Earth. Giant Planets: Exploring the Outer Solar System will take advantage of the excitement generated by the Cassini mission and bring planetary and origins research and discoveries to students and the public. It will be organized around four thematic areas: Our Solar System; Colossal Worlds; Moons, Rings, and Fields; and Make Space for Kids. Giant Planets will open in 2007. This talk will focus on the importance of making Earth comparisons in the conceptual design of each exhibit and will show several examples of how these comparisons were manifested in

  17. Sutureless 25-Gauge Pars Plana Vitrectomy Combined with Retropupillary Fixation of an Iris-Claw Intraocular Lens

    PubMed Central

    Chalkiadakis, Spyridon E.; Parikakis, Efstratios A.; Taylor, Simon R.J.

    2016-01-01

    Background The surgical case of a dropped intraocular lens inside the vitreous cavity constitutes a real challenge for the operating surgeon. Herein, we describe a case series where an alternative optical rehabilitation technique for late intraocular lens-bag complex dislocation has been used. Methods A modern vitrectomy device was used to remove the capsule with the dropped intraocular lens using sutureless 25-gauge pars plana vitrectomy. To ensure a better aesthetic result, with faster patient recovery and a reduced number of operations, the whole procedure was performed during the same operating session; an iris-claw intraocular lens for aphakia was selected for implantation. The implant was passed behind the constricted iris with the concave surface facing it. The lens was grasped with the manufacturer's holding forceps and fixed onto the posterior surface of the iris using the special enclavation needles. Results We have operated 12 eyes in two different clinical centres successfully, with minimal intra- and/or postoperative complications. Conclusion We believe that this is a viable solution for the visual rehabilitation of patients, who would otherwise need more than one operation for a lens exchange. PMID:27790132

  18. Development of a Loop-Mediated Isothermal Amplification Assay Targeting the mpb64 Gene for Diagnosis of Intraocular Tuberculosis

    PubMed Central

    Balne, Praveen Kumar; Barik, Manas Ranjan; Sharma, Savitri

    2013-01-01

    A loop-mediated isothermal amplification (LAMP) assay targeting the mpb64 gene for the diagnosis of intraocular tuberculosis was highly specific (100%), sensitive (85.7%), rapid, and easy to perform. The LAMP assay can be an alternative to conventional PCR for the diagnosis of ocular tuberculosis in resource-limited settings. PMID:23966513

  19. [Use of intraocular fluid in the medico-legal practice in diagnosing fatal poisoning with various psychoactive substances].

    PubMed

    Jabłoński, Christian; Sybirska, Halina

    2002-01-01

    In this paper results of the research on the usefulness of toxicological analysis relating to narcotics in intraocular fluid have been presented. The examined material comprised intraocular fluids and blood samples collected from 332 deceased suspected of being intoxicated or poisoned with psychoactive agents. The cases in which death resulted from injuries and those where an individual took drugs before his or her death were also considered. Drug analysis was carried out by fluorescence polarization immunoassay (FPIA). In both biological fluids the degree of hydratation was determined. Ethyl alcohol, opiates, barbiturates and benzodiazepines were found in all the examined cases. In few cases ethanol substitutes such as isopropyl alcohol, ethylene glycol and methyl alcohol were indicated. Results of the quantitative examinations were divided into sets according to the kind of xenobiotic and then on the basics of concentration of the substance found in the blood and vitreous body 2 different groups were separated in each set. Statistic analysis of the correlations among xenobiotic concentrations in both organic fluids was also performed. The obtained findings allow to assume that intraocular fluid can be used for toxicological diagnosis of poisonings with psycho-active agents. The analytical results for intraocular fluid not only confirms the result for blood but also makes it credible. In single cases it can be a sufficient basis to determine and recognize psychoactive agents in the deceased.

  20. Role of intraocular Leptospira infections in the pathogenesis of Equine Recurrent Uveitis in the Southern United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To investigate the role of intraocular leptospiral infections in horses with Equine Recurrent Uveitis (ERU) in the southern United States, blood and ocular fluid samples were collected from horses with a history and ocular findings consistent with ERU. Samples were also obtained from control horses ...

  1. Intraocular tumor antigen drains specifically to submandibular lymph nodes, resulting in an abortive cytotoxic T cell reaction.

    PubMed

    Boonman, Zita F H M; van Mierlo, Geertje J D; Fransen, Marieke F; Franken, Kees L M C; Offringa, Rienk; Melief, Cornelis J M; Jager, Martine J; Toes, René E M

    2004-02-01

    Ocular immune privilege is considered essential in the protection against sight-threatening immune responses, as illustrated by the ability of the ocular environment to permit the growth of tumors that are rejected when implanted at other sites. Although several studies indicate that soluble Ag can drain directly into the spleen when injected into the anterior chamber, the primary site of intraocular tumor Ag presentation to tumor-specific CTLs has not been studied. To gain a better understanding of the mechanism involved in ocular immune privilege, we examined to which lymphoid organs anterior chamber tumor Ags primarily drain. Our data show that intraocular tumor Ag drains exclusively to the submandibular lymph nodes, resulting in activation of tumor-specific CTLs, whereas no Ag drainage was found in spleen. However, these tumor-specific CTLs do not distribute systemically and, as a consequence, intraocular tumor growth is unhampered. A similar lack of CTL efficacy has been observed in mice bearing s.c. tumors, which is converted to a systemic tumoricidal CTL response by administration of agonistic anti-CD40 mAb. In contrast, systemic anti-CD40 treatment of eye tumor-bearing mice did not result in mobilizing tumor-specific CTLs or tumor eradication. Together, these results show that intraocular tumor Ag drains to regional lymph nodes for activation of tumor-specific CTLs. However, the induced tumor-specific immunity is insufficient for tumor clearance, even combined with otherwise highly effective immune intervention protocols.

  2. Localized pulses exhibiting a missilelike slow decay.

    PubMed

    Shaarawi, Amr M; Maged, Maha A; Besieris, Ioannis M; Hashish, Essam

    2006-08-01

    We investigate the quasi-missile behavior of known localized wave solutions, such as the modified power spectrum and splash pulses. We demonstrate that source-free localized waves can exhibit slow decay rates analogous to Wu's missile solutions, which are characterized by an amplitude decay rate slower than 1/R over an unlimited range. When excited from a finite aperture, the missilelike decay is not exhibited by all localized waves showing such behavior in the source-free situation. On the other hand, localized wave missiles generated from a finite aperture have peaks that exhibit quasi-missile decay. In an extended intermediate range between the near- and the far-field regions, these pulses decay at a rate slower than 1/R before switching to the usual 1/R decay.

  3. Localized pulses exhibiting a missilelike slow decay

    NASA Astrophysics Data System (ADS)

    Shaarawi, Amr M.; Maged, Maha A.; Besieris, Ioannis M.; Hashish, Essam

    2006-08-01

    We investigate the quasi-missile behavior of known localized wave solutions, such as the modified power spectrum and splash pulses. We demonstrate that source-free localized waves can exhibit slow decay rates analogous to Wu's missile solutions, which are characterized by an amplitude decay rate slower than 1/R over an unlimited range. When excited from a finite aperture, the missilelike decay is not exhibited by all localized waves showing such behavior in the source-free situation. On the other hand, localized wave missiles generated from a finite aperture have peaks that exhibit quasi-missile decay. In an extended intermediate range between the near- and the far-field regions, these pulses decay at a rate slower than 1/R before switching to the usual 1/R decay.

  4. The Gravity- Powered Calculator, a Galilean Exhibit

    NASA Astrophysics Data System (ADS)

    Cerreta, Pietro

    2014-04-01

    The Gravity-Powered Calculator is an exhibit of the Exploratorium in San Francisco. It is presented by its American creators as an amazing device that extracts the square roots of numbers, using only the force of gravity. But if you analyze his concept construction one can not help but recall the research of Galileo on falling bodies, the inclined plane and the projectile motion; exactly what the American creators did not put into prominence with their exhibit. Considering the equipment only for what it does, in my opinion, is very reductive compared to the historical roots of the Galilean mathematical physics contained therein. Moreover, if accurate deductions are contained in the famous study of S. Drake on the Galilean drawings and, in particular on Folio 167 v, the parabolic paths of the ball leaping from its launch pad after descending a slope really actualize Galileo's experiments. The exhibit therefore may be best known as a `Galilean calculator'.

  5. Unexpected Roles for Toll-Like Receptor 4 and TRIF in Intraocular Infection with Gram-Positive Bacteria

    PubMed Central

    Parkunan, Salai Madhumathi; Randall, C. Blake; Coburn, Phillip S.; Astley, Roger A.; Staats, Rachel L.

    2015-01-01

    Inflammation caused by infection with Gram-positive bacteria is typically initiated by interactions with Toll-like receptor 2 (TLR2). Endophthalmitis, an infection and inflammation of the posterior segment of the eye, can lead to vision loss when initiated by a virulent microbial pathogen. Endophthalmitis caused by Bacillus cereus develops as acute inflammation with infiltrating neutrophils, and vision loss is potentially catastrophic. Residual inflammation observed during B. cereus endophthalmitis in TLR2−/− mice led us to investigate additional innate pathways that may trigger intraocular inflammation. We first hypothesized that intraocular inflammation during B. cereus endophthalmitis would be controlled by MyD88- and TRIF-mediated signaling, since MyD88 and TRIF are the major adaptor molecules for all bacterial TLRs. In MyD88−/− and TRIF−/− mice, we observed significantly less intraocular inflammation than in eyes from infected C57BL/6J mice, suggesting an important role for these TLR adaptors in B. cereus endophthalmitis. These results led to a second hypothesis, that TLR4, the only TLR that signals through both MyD88 and TRIF signaling pathways, contributed to inflammation during B. cereus endophthalmitis. Surprisingly, B. cereus-infected TLR4−/− eyes also had significantly less intraocular inflammation than infected C57BL/6J eyes, indicating an important role for TLR4 in B. cereus endophthalmitis. Taken together, our results suggest that TLR4, TRIF, and MyD88 are important components of the intraocular inflammatory response observed in experimental B. cereus endophthalmitis, identifying a novel innate immune interaction for B. cereus and for this disease. PMID:26195555

  6. Influence of Corneal Opacity on Intraocular Pressure Assessment in Patients with Lysosomal Storage Diseases

    PubMed Central

    Politino, Giuseppe; Schmidtmann, Irene; Lorenz, Katrin; Bell, Katharina; Pfeiffer, Norbert; Pitz, Susanne

    2017-01-01

    Aims To investigate an influence of mucopolysaccharidosis (MPS)- and Morbus Fabry-associated corneal opacities on intraocular pressure (IOP) measurements and to evaluate the concordance of the different tonometry methods. Methods 25 MPS patients with or without corneal clouding, 25 Fabry patients with cornea verticillata ≥ grade 2 and 25 healthy age matched controls were prospectively included into this study. Outcome measures: Goldmann applanation tonometry (GAT); palpatory assessment of IOP; Goldmann-correlated intraocular pressure (IOPg), corneal-compensated intraocular pressure (IOPcc), corneal resistance factor (CRF) and corneal hysteresis (CH) assessed by Ocular Response Analyzer (ORA); central corneal thickness (CCT) and density assessed with Pentacam. Statistical analysis was performed using linear mixed effect models and Spearman correlation coefficients. The concordance between tonometry methods was assessed using Bland-Altman analysis. Results There was no relevant difference between study groups regarding median GAT, IOPg, IOPcc and CCT measurements. The limits of agreement between GAT and IOPcc/IOPg/palpatory IOP in MPS were: [-11.7 to 12.1mmHg], [-8.6 to 15.5 mmHg] and [- 5.4 to 10.1 mmHg] respectively. Limits of agreement were less wide in healthy subjects and Fabry patients. Palpatory IOP was higher in MPS than in healthy controls and Fabry patients. Corneal opacity correlated more strongly with GAT, IOPg, CH, CRF, CCT and corneal density in MPS (r = 0.4, 0.5, 0.5, 0.7, 0.6, 0.6 respectively) than in Fabry patients (r = 0.3, 0.2, -0.03, 0.1, 0.3, -0.2 respectively). In contrast, IOPcc revealed less correlation with corneal opacity than GAT in MPS (r = 0.2 vs. 0.4). Conclusions ORA and GAT render less comparable IOP-values in patients suffering from MPS-associated corneal opacity in comparison to Fabry and healthy controls. The IOP seems to be overestimated in opaque MPS-affected corneas. GAT, IOPg and biomechanical parameters of the cornea

  7. Intraocular and extraocular cameras for retinal prostheses: Effects of foveation by means of visual prosthesis simulation

    NASA Astrophysics Data System (ADS)

    McIntosh, Benjamin Patrick

    Blindness due to Age-Related Macular Degeneration and Retinitis Pigmentosa is unfortunately both widespread and largely incurable. Advances in visual prostheses that can restore functional vision in those afflicted by these diseases have evolved rapidly from new areas of research in ophthalmology and biomedical engineering. This thesis is focused on further advancing the state-of-the-art of both visual prostheses and implantable biomedical devices. A novel real-time system with a high performance head-mounted display is described that enables enhanced realistic simulation of intraocular retinal prostheses. A set of visual psychophysics experiments is presented using the visual prosthesis simulator that quantify, in several ways, the benefit of foveation afforded by an eye-pointed camera (such as an eye-tracked extraocular camera or an implantable intraocular camera) as compared with a head-pointed camera. A visual search experiment demonstrates a significant improvement in the time to locate a target on a screen when using an eye-pointed camera. A reach and grasp experiment demonstrates a 20% to 70% improvement in time to grasp an object when using an eye-pointed camera, with the improvement maximized when the percept is blurred. A navigation and mobility experiment shows a 10% faster walking speed and a 50% better ability to avoid obstacles when using an eye-pointed camera. Improvements to implantable biomedical devices are also described, including the design and testing of VLSI-integrable positive mobile ion contamination sensors and humidity sensors that can validate the hermeticity of biomedical device packages encapsulated by hermetic coatings, and can provide early warning of leaks or contamination that may jeopardize the implant. The positive mobile ion contamination sensors are shown to be sensitive to externally applied contamination. A model is proposed to describe sensitivity as a function of device geometry, and verified experimentally. Guidelines are

  8. An intraocular drug delivery system using targeted nanocarriers attenuates retinal ganglion cell degeneration.

    PubMed

    Zhao, Lei; Chen, Guojun; Li, Jun; Fu, Yingmei; Mavlyutov, Timur A; Yao, Annie; Nickells, Robert W; Gong, Shaoqin; Guo, Lian-Wang

    2017-02-10

    Glaucoma is a common blinding disease characterized by loss of retinal ganglion cells (RGCs). To date, there is no clinically available treatment directly targeting RGCs. We aim to develop an RGC-targeted intraocular drug delivery system using unimolecular micelle nanoparticles (unimNPs) to prevent RGC loss. The unimNPs were formed by single/individual multi-arm star amphiphilic block copolymer poly(amidoamine)-polyvalerolactone-poly(ethylene glycol) (PAMAM-PVL-PEG). While the hydrophobic PAMAM-PVL core can encapsulate hydrophobic drugs, the hydrophilic PEG shell provides excellent water dispersity. We conjugated unimNPs with the cholera toxin B domain (CTB) for RGC-targeting and with Cy5.5 for unimNP-tracing. To exploit RGC-protective sigma-1 receptor (S1R), we loaded unimNPs with an endogenous S1R agonist dehydroepiandrosterone (DHEA) as an FDA-approved model drug. These unimNPs produced a steady DHEA release in vitro for over two months at pH7.4. We then co-injected (mice, intraocular) unimNPs with the glutamate analog N-methyl-d-aspartate (NMDA), which is excito-toxic and induces RGC death. The CTB-conjugated unimNPs (i.e., targeted NPs) accumulated at the RGC layer and effectively preserved RGCs at least for 14days, whereas the unimNPs without CTB (i.e., non-targeted NPs) showed neither accumulation at nor protection of NMDA-treated RGCs. Consistent with S1R functions, targeted NPs relative to non-targeted NPs showed markedly better inhibitory effects on apoptosis and oxidative/inflammatory stresses in the RGC layer. Hence, the DHEA-loaded, CTB-conjugated unimNPs represent an RGC/S1R dual-targeted nanoplatform that generates an efficacious template for further development of a sustainable intraocular drug delivery system to protect RGCs, which may be applicable to treatments directed at glaucomatous pathology.

  9. 18 CFR 32.2 - Required exhibits.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... facilities used for the generation and transmission of electric energy, indicating on said map the points... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Required exhibits. 32.2 Section 32.2 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT...

  10. 18 CFR 32.2 - Required exhibits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... facilities used for the generation and transmission of electric energy, indicating on said map the points... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Required exhibits. 32.2 Section 32.2 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT...

  11. 18 CFR 34.4 - Required exhibits.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Required exhibits. 34.4 Section 34.4 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER ACT APPLICATION FOR AUTHORIZATION OF THE ISSUANCE...

  12. FluxBase: An Interactive Art Exhibition.

    ERIC Educational Resources Information Center

    Huntley, Joan S.; Partridge, Michael

    1992-01-01

    Describes a computer program that gives Fluxus exhibition attendees an opportunity to experience the Flux objects in the spirit in which they were originally created. Suggests that the computer program provides a virtual approximation to the original art works without damaging them. (RS)

  13. 32 CFR 705.24 - Exhibits.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... be displayed in any appropriate location or event (including commercially owned spaces such as... for Navy exhibits in events of international or national scope, or those requiring major coordination... will be used. See Armed Forces Request Form, § 705.36. (4) Requests for exceptions to policy...

  14. 32 CFR 705.24 - Exhibits.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... be displayed in any appropriate location or event (including commercially owned spaces such as... for Navy exhibits in events of international or national scope, or those requiring major coordination... will be used. See Armed Forces Request Form, § 705.36. (4) Requests for exceptions to policy...

  15. 32 CFR 705.24 - Exhibits.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... be displayed in any appropriate location or event (including commercially owned spaces such as... for Navy exhibits in events of international or national scope, or those requiring major coordination... will be used. See Armed Forces Request Form, § 705.36. (4) Requests for exceptions to policy...

  16. 32 CFR 705.24 - Exhibits.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... be displayed in any appropriate location or event (including commercially owned spaces such as... for Navy exhibits in events of international or national scope, or those requiring major coordination... will be used. See Armed Forces Request Form, § 705.36. (4) Requests for exceptions to policy...

  17. Do Online Students Exhibit Different Learning Styles

    ERIC Educational Resources Information Center

    Hausler, Joel; Sanders, John W.; Young, Barbara

    2007-01-01

    We examined the relationship between learning styles and student type. This research seeks to examine if online students exhibit different learning styles from onsite students; and, if so, what accommodations relating to learning style differences may be made for online students? Students (N = 80) were asked to complete an online survey in order…

  18. The medial prefrontal cortex exhibits money illusion

    PubMed Central

    Weber, Bernd; Rangel, Antonio; Wibral, Matthias; Falk, Armin

    2009-01-01

    Behavioral economists have proposed that money illusion, which is a deviation from rationality in which individuals engage in nominal evaluation, can explain a wide range of important economic and social phenomena. This proposition stands in sharp contrast to the standard economic assumption of rationality that requires individuals to judge the value of money only on the basis of the bundle of goods that it can buy—its real value—and not on the basis of the actual amount of currency—its nominal value. We used fMRI to investigate whether the brain's reward circuitry exhibits money illusion. Subjects received prizes in 2 different experimental conditions that were identical in real economic terms, but differed in nominal terms. Thus, in the absence of money illusion there should be no differences in activation in reward-related brain areas. In contrast, we found that areas of the ventromedial prefrontal cortex (vmPFC), which have been previously associated with the processing of anticipatory and experienced rewards, and the valuation of goods, exhibited money illusion. We also found that the amount of money illusion exhibited by the vmPFC was correlated with the amount of money illusion exhibited in the evaluation of economic transactions. PMID:19307555

  19. Comic Strips to Accompany Science Museum Exhibits

    ERIC Educational Resources Information Center

    Chung, Beom Sun; Park, Eun-mi; Kim, Sang-Hee; Cho, Sook-kyoung; Chung, Min Suk

    2016-01-01

    Science museums make the effort to create exhibits with amusing explanations. However, existing explanation signs with lengthy text are not appealing, and as such, visitors do not pay attention to them. In contrast, conspicuous comic strips composed of simple drawings and humors can attract science museum visitors. This study attempted to reveal…

  20. After Terror Charges, Artist Exhibits Academic Freedom

    ERIC Educational Resources Information Center

    Wilson, Robin

    2008-01-01

    Steven Kurtz, a professor of visual studies at the State University of New York, has been working with various bacteria as part of his counterculture exhibit artworks for nearly 20 years. Four years ago, federal agents raided his home in a bioterrorism investigation. The federal agents had been called to the house by local police officers…

  1. 18 CFR 156.5 - Exhibits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... such enterprises or operations, a detailed explanation of each such relationship, including the... relationship. (5) Exhibit F—Location of facilities. A geographical map of suitable scale and detail showing all... proposed customers; derivation of numbers of customers proposed to be served; individual consumer peak...

  2. 18 CFR 157.14 - Exhibits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... explanation of each such relationship, including the percentage of voting strength represented by such... detailed explanation of each such relationship. (5) Exhibit E—Other pending applications and filings. A... abandoned. This map, or an additional map, shall clearly show the relationship of the new facilities to...

  3. 18 CFR 153.8 - Required exhibits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... LNG, evidence that an appropriate and qualified concern will properly and safely receive or deliver such LNG, including a report containing detailed engineering and design information. The Commission... Office of Energy Projects, 888 First Street, NE., Washington, DC 20426; (6) Exhibit E-1. If the...

  4. 18 CFR 50.7 - Applications: exhibits.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Applications: exhibits. 50.7 Section 50.7 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER ACT APPLICATIONS FOR PERMITS TO SITE...

  5. 18 CFR 50.7 - Applications: exhibits.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 18 Conservation of Power and Water Resources 1 2014-04-01 2014-04-01 false Applications: exhibits. 50.7 Section 50.7 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER ACT APPLICATIONS FOR PERMITS TO SITE...

  6. 18 CFR 153.8 - Required exhibits.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... LNG, evidence that an appropriate and qualified concern will properly and safely receive or deliver such LNG, including a report containing detailed engineering and design information. The Commission... Office of Energy Projects, 888 First Street, NE., Washington, DC 20426; (6) Exhibit E-1. If the...

  7. 18 CFR 156.5 - Exhibits.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... separate volume or volumes shall indicate on the cover thereof applicant's name and bear Docket No. CP... an equivalent Btu basis. (12) Exhibit K—Cost of facilities. A detailed estimate of total capital cost.... (vii) A balance sheet and income statement (12 months) of most recent date available....

  8. 18 CFR 156.5 - Exhibits.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... separate volume or volumes shall indicate on the cover thereof applicant's name and bear Docket No. CP... an equivalent Btu basis. (12) Exhibit K—Cost of facilities. A detailed estimate of total capital cost.... (vii) A balance sheet and income statement (12 months) of most recent date available....

  9. Twenty-four-hour intraocular pressure related changes following adjuvant selective laser trabeculoplasty for normal tension glaucoma.

    PubMed

    Lee, Jacky W Y; Fu, Lin; Chan, Jonathan C H; Lai, Jimmy S M

    2014-12-01

    To investigate intraocular pressure (IOP) related patterns before and after selective laser trabeculoplasty (SLT) for normal tension glaucoma (NTG).In this prospective cohort study, 18 NTG patients underwent SLT. Success was defined as IOP reduction ≥ 20% by Goldmann applanation tonometry. 24-hour IOP-related pattern recording with a contact lens sensor (CLS) (SENSIMED Triggerfish, Sensimed, Switzerland) was done before (baseline) and 1 month after SLT. A cosine function was fitted to the mean CLS patterns for each individual in the SLT success and non-success groups and the amplitude before and after SLT was calculated. Diurnal, nocturnal, and 24-hour CLS pattern local variability was determined for pre- and post-SLT sessions. Cosine amplitude and variability were compared before and after SLT by group using paired t-tests, with α = 0.05. Patients (11 women, 7 men) had a mean age of 65.1 ± 13.7 years. Mean IOP was 15.3 ± 2.2 mm Hg at baseline and was reduced by 17.0% to 12.7 ± 1.8 mm Hg 1 month after SLT (P = 0.001). SLT was successful in 8 patients (44%). The amplitude of the fitted cosine was reduced by 24.6% in the success group, but displayed an amplitude increase of 19.2% post-SLT in the non-success group. Higher diurnal local variability of the CLS pattern was observed after SLT in non-success subjects (P = 0.002), while nocturnal variability showed no significant change. The increase in diurnal variability in the non-success group led to an increase in 24-hour variability in this group (P = 0.001). No change in local variability (diurnal, nocturnal, and 24-hour) was seen in the success group. The IOP-related pattern cosinor amplitude was reduced in NTG patients with a successful SLT treatment whereas the non-success group exhibited an increase of cosine amplitude. Higher diurnal and 24-hour CLS pattern variability was observed in non-success patients 1 month post-SLT.

  10. Photoreversibility and Biocompatibility of Polydimethylsiloxane-Coumarin as Adjustable Intraocular Lens Material.

    PubMed

    Jellali, Rachid; Bertrand, Virginie; Alexandre, Michaël; Rosière, Nancy; Grauwels, Magda; De Pauw-Gillet, Marie-Claire; Jérôme, Christine

    2017-03-15

    Polydimethylsiloxane (PDMS) constitutes an interesting material for a variety of biomedical applications, especially as intraocular lenses (IOLs), for its excellent transparency. In this work, a photoreversible PDMS-coumarin network, whose shape and properties can be adjusted postoperatively in a noninvasive manner, is developed. The synthesis of PDMS-coumarin is achieved by amidation of a coumarin acid chloride derivative with amine-functionalized PDMSs. Under exposure of λ > 300 nm, these polymers can be cured by dimerization of coumarin. The cured polymers can be uncrosslinked via photocleavage of cyclobutane dimers upon illumination at λ < 290 nm. The diffusion of linear PDMSs in a crosslinked network and the controlled shape modification are studied, which demonstrate that these polymers are good candidates for adjustable IOL application. IOL disks prepared from these materials show high hydrophobicity and good transparency. In vitro cytotoxicity, lens epithelial cell adhesion assays, and rabbit host reaction against implanted disks demonstrate the biocompatibility of the polymer.

  11. Bilateral uveitis after phakic intraocular lens implantation and management with adalimumab.

    PubMed

    Soheilian, Masoud; Jabbarpourbonyadi, Mohammadhossein; Soheilian, Roham; Peyman, Gholam A

    2012-06-01

    A 25-year-old woman with myopia who had an AC pIOL implantation in the left eye and posterior chamber pIOL implantation in the right eye developed bilateral granulomatous panuveitis 2 months after the second surgery. Physical examination showed bilateral Koeppe and Busacca nodules. Fluorescein angiography showed diffuse vascular and retinal pigment epithelial leakage in both eyes. With assessment of sympathetic ophthalmia, treatment with a high-dose systemic steroid was started. Oral cyclosporine and azathioprine were later added. Because the uveitis was not controlled, adalimumab was added. After 6 doses of adalimumab (40 mg subcutaneously), the uveitis subsided and corticosteroid and other immunosuppressive agents were tapered. Refractive AC pIOL implantation should be added to the list of intraocular procedures that may induce sympathetic ophthalmia. Adalimumab may have a therapeutic role in its management.

  12. Intraocular deposition of metallic fragments during phacoemulsification: possible causes and effects.

    PubMed

    Dunbar, C M; Goble, R R; Gregory, D W; Church, W C

    1995-01-01

    We undertook a prospective slit lamp examination of 56 eyes which had undergone routine phacoemulsification, in order to determine the incidence of metallic intraocular foreign bodies. Characteristic small reflective particles were noted in 86%, with a mean of 5.1 particles per affected eye. No accompanying clinical problems were seen. The used phacoemulsification needles were examined with colour photography and scanning electron microscopy. A characteristic pattern of wear was observed, corresponding to an area under the plastic irrigating sleeve rather than at the tip. This suggests cavitation erosion rather than instrument contacts as the cause. Titanium alloy contains 6% aluminium, 4% vanadium and 0.25% iron. All its constituents may corrode and leach from the surface of the metal when in contact with body fluids and have been implicated in numerous adverse biological processes.

  13. [The growth behavior of mouse fibroblasts on intraocular lens surface of various silicone and PMMA materials].

    PubMed

    Kammann, J; Kreiner, C F; Kaden, P

    1994-08-01

    Experience with intraocular lenses (IOL) made of PMMA dates back ca. 40 years, while silicone IOLs have been in use for only about 10 years. The biocompatibility of PMMA and silicone caoutchouc was tested in a comparative study investigating the growth of mouse fibroblasts on different IOL materials. Spectrophotometric determination of protein synthesis and liquid scintillation counting of DNA synthesis were carried out. The spreading of cells was planimetrically determined, and the DNA synthesis of individual cells in direct contact with the test sample was tested. The results showed that the biocompatibility of silicone lenses made of purified caoutchouc is comparable with that of PMMA lenses; there is no statistically significant difference. However, impurities arising during material synthesis result in a statistically significant inhibition of cell growth on the IOL surfaces.

  14. Iris-fixated phakic intraocular lens implantation for correction of high myopia in microspherophakia.

    PubMed

    Moshirfar, Majid; Meyer, Jay J; Schliesser, Joshua A; Espandar, Ladan; Chang, Joann C

    2010-04-01

    We report the refractive correction of high myopia in a 23-year-old patient with idiopathic microspherophakia using iris-fixated phakic intraocular lenses (pIOLs) (Verisyse/Artisan). Four years after bilateral implantation, the uncorrected distance visual acuity was 20/25 with a correction of 20/20(-1) in both eyes. No intraoperative or postoperative complications occurred. Iris-fixated pIOLs are not recommended for every patient with microspherophakia. However, this procedure may be an option in microspherophakic patients with appropriate anterior chamber depth and no history of lens dislocation who are likely to comply with annual eye examinations. Follow-up should include monitoring the endothelial cell count and biomicroscopy for adequate space between the pIOL, the natural crystalline lens, and the corneal endothelium. Scheimpflug photography can be a valuable tool in such cases.

  15. Complications of foldable intraocular lenses requiring explantation or secondary intervention--2007 survey update.

    PubMed

    Mamalis, Nick; Brubaker, Jacob; Davis, Don; Espandar, Ladan; Werner, Liliana

    2008-09-01

    The tenth annual survey of complications associated with foldable intraocular lenses (IOLs) requiring explantation or secondary intervention was sent to members of the American Society of Cataract and Refractive Surgery and the European Society of Cataract and Refractive Surgeons. Preoperative data about visual acuity, patient signs and symptoms, and complications requiring IOL removal were evaluated. Complications were then tabulated for each of the following major foldable IOL groups: 1-piece (plate) silicone, 1-piece hydrophobic acrylic with haptics, 3-piece silicone, 3-piece hydrophobic acrylic, 3-piece hydrophilic acrylic (hydrogel), 3-piece unknown, multifocal acrylic, and multifocal silicone. One hundred forty-two surveys were returned for evaluation. Dislocation/decentration, incorrect IOL power, glare/optical aberrations, and IOL calcification were the most common reasons for removing foldable IOLs. Good surgical technique, accurate IOL power measurements, and high manufacturing standards for foldable IOL materials and designs are the most important factors in preventing complications.

  16. Oxygen saturation changes in the optic nerve head during acute intraocular pressure elevation in monkeys

    NASA Astrophysics Data System (ADS)

    Khoobehi, Bahram; Kawano, Hiroyuki; Ning, Jinfeng; Burgoyne, Claude F.; Rice, David A.; Khan, Fareeha; Thompson, Hilary W.; Beach, James M.

    2009-02-01

    Background and Objective: To evaluate the effect of an acute elevated intraocular pressure (IOP) on oxygen saturation of structures of the optic nerve head. Study Design/Materials and Methods: In the cynomolgus monkey eye, IOP was set to 10 mm Hg, and then raised to 30, 45, and 55 mm Hg. The ONH and overlying vessels were imaged using a fundus camera attached to a hyperspectral imaging system (HSI) at 10 and 30 minutes after IOP elevation. Results: Raising IOP from 10 to 30 mm Hg did not significantly (P < 0.0001) change saturation in vessels or ONH tissue structures but at 55 mm Hg, all structures showed significant reduction. Conclusions: Quantitative assay of the blood oxygen saturation in structures on the surface and overlying the optic nerve head is possible using hyperspectral imaging techniques.

  17. Compared optical performances of multifocal and monofocal intraocular lenses (contrast sensitivity and dynamic visual acuity)

    PubMed Central

    Williamson, W; Poirier, L; Coulon, P; Verin, P

    1994-01-01

    The functional results (contrast sensitivity and dynamic visual acuity) of 19 multifocal (3M design) and 14 all polymethylmethacrylate biconvex monofocal intraocular lenses (IOLs), 6 mm in optical diameter were compared. Best corrected visual acuity was > or = 8/10 (Monoyer chart) Parinaud 2 in all cases. Major differences of functional performance in favour of monofocal IOLs were found outside standard conditions of vision (low contrast and illumination levels). A significant difference in contrast sensitivity was found for each spatial frequency in favour of multifocal IOLs (0.0016 < p < 0.05). Mesopic vision was statistically higher in the monofocal IOL group (p = 0.0015). Moreover, dynamic visual acuity allowed accurate evaluation of the difference in performance between these two models of implant. In view of these results multifocal IOLs should be reserved for patients with normal psychosensitive adaptation; an ocular pathology that could alter contrast sensitivity or mesopic vision is a contraindication for multifocal IOLs. PMID:8199107

  18. Posterior rat eye during acute intraocular pressure elevation studied using polarization sensitive optical coherence tomography

    PubMed Central

    Fialová, Stanislava; Augustin, Marco; Fischak, Corinna; Schmetterer, Leopold; Handschuh, Stephan; Glösmann, Martin; Pircher, Michael; Hitzenberger, Christoph K.; Baumann, Bernhard

    2016-01-01

    Polarization sensitive optical coherence tomography (PS-OCT) operating at 840 nm with axial resolution of 3.8 µm in tissue was used for investigating the posterior rat eye during an acute intraocular pressure (IOP) increase experiment. IOP was elevated in the eyes of anesthetized Sprague Dawley rats by cannulation of the anterior chamber. Three dimensional PS-OCT data sets were acquired at IOP levels between 14 mmHg and 105 mmHg. Maps of scleral birefringence, retinal nerve fiber layer (RNFL) retardation and relative RNFL/retina reflectivity were generated in the peripapillary area and quantitatively analyzed. All investigated parameters showed a substantial correlation with IOP. In the low IOP range of 14-45 mmHg only scleral birefringence showed statistically significant correlation. The polarization changes observed in the PS-OCT imaging study presented in this work suggest that birefringence of the sclera may be a promising IOP-related parameter to investigate. PMID:28101419

  19. Successful treatment of intracardiac and intraocular blastomycosis in a dog with combination azole therapy.

    PubMed

    Langlois, Daniel K; Pelosi, Augusta; Kruger, John M

    2013-01-01

    A 4 yr old spayed female Labrador retriever with clinical signs of blindness, cutaneous lesions, coughing, inappetence, and lethargy was diagnosed with disseminated blastomycosis based on cytologic (skin and lymph node aspirates) and histopathologic (skin biopsy) examinations of tissue samples. The dog deteriorated clinically during hospitalization and developed sustained ventricular tachycardia. Echocardiography revealed pericardial effusion, a nodule associated with the left ventricular papillary muscle, and a right atrial mural lesion. Therapy for myocardial performance and glaucoma was initiated. A combination of itraconazole and fluconazole successfully treated the dog. The dog regained vision in the left eye (oculus sinister [OS]) and had no residual cardiac disease detectable by either electrocardiography or echocardiography. This report is unique in documenting survival from intracardiac blastomycosis and in the use of combination azole therapy for treating disseminated disease with intraocular involvement.

  20. Intraocular Ossification in the GSP/pe Chicken With Imperfect Albinism.

    PubMed

    Shibuya, K; Kinoshita, K; Mizutani, M; Oshima, A; Yamashita, R; Matsuda, Y

    2015-07-01

    The eyes of 2 male and 2 female GSP/pe chickens, the imperfect albino strain, were investigated at 52 weeks of age. Aged chickens of the GSP/pe colony became blind with bilateral ocular enlargement and opaque lenses. Affected eyes (bilateral in 2 males and unilateral in 2 females) were hard and difficult to section; histologic specimens were processed after decalcification. A large portion of the posterior chamber was occupied by cancellous bone containing fibrous and cartilaginous foci. Osseous tissues developed adjacent to the choroid, and no retinal pigment epithelium (RPE) was detected between osseous tissues and the choroid. Small segments of degenerate neuronal retina were scattered in the osseous tissue. The irises and ciliary bodies were deformed by osseous tissue, and the lenses had severe cataracts. These observations suggest that the intraocular osseous tissue may be derived from RPE in the hereditary incomplete-albino strain of chickens.