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Sample records for partial-thickness macular hole

  1. [Macular serpiginous choroiditis complicated by macular hole].

    PubMed

    Brănişteanu, D; Moraru, Andreea

    2014-01-01

    Macular serpiginouschoroiditis is a rare variant of serpiginous choroiditis characterized by a severe recurrent inflammation of both central choroid and retinal pigment epithelium. Visual prognosis is severe due to subsequent distruction of retinal structures. Permanent central visual loss is the consequence of retinal pigment epithelium hyper or hypoplasia and/or subretinal neovascularization leading to fibrous scarring. This article reports the unusual case of rapid development of a macular hole soon after the onset of characteristic clinical features. Despite anti-inflammatory treatment and successful macular hole surgery the visual function remained significantly impaired by secondary central retinal pigment epithelium changes.

  2. Traumatic macular hole from intentional basketball overinflation.

    PubMed

    Yonekawa, Yoshihiro; Miller, John B; Turalba, Angela V; Eliott, Dean

    2013-01-01

    We report a new mechanism of ocular trauma. A basketball was intentionally overinflated until it exploded, resulting in corneal edema, hyphema, iritis, vitreous hemorrhage, commotio retinae, and a macular hole. The macular hole did not close after observation and subsequent pars plana vitrectomy with posterior hyaloid removal, but a repeat vitrectomy with internal limiting membrane peeling resulted in hole closure. Basketball overinflation to the point of explosion is a potentially blinding practice of which the public and manufacturers should be made aware.

  3. Management of traumatic macular holes: case report.

    PubMed

    Brasil, Oswaldo Ferreira Moura; Brasil, Oswaldo Moura

    2008-01-01

    Traumatic macular hole is a disease whose pathogenesis is not fully understood and the best treatment guideline is controversial. We report 2 cases of traumatic macular hole with different treatment approaches. In the first case, a 9-year-old boy presented with a traumatic macular hole secondary to blunt ocular trauma with a stone, and initial vision of 20/300. He underwent surgical repair and his final vision was 20/70 with hole closure after a 1 year follow-up. In the second case, a 20-year-old woman suffered a penetrating bullet wound on the left side of her forehead. The injury caused optic nerve head avulsion in the left eye with loss of light perception. The right eye had a traumatic macular hole and signs suggestive of sclopetaria chorioretinitis, with 20/60 vision. This case was initially observed and vision improved to 20/30 with reduction of the hole diameter. Vision and hole diameter remained stable after 8 months.

  4. Macular hole surgery using silicone oil tamponade

    PubMed Central

    Karia, N; Laidlaw, A; West, J; Ezra, E; Gregor, M

    2001-01-01

    BACKGROUND/AIMS—Most surgeons performing macular hole surgery using long acting gas recommend strict postoperative face down posturing for 10-15 days. Patients with chronic systemic illness such as arthritis may be unable to carry out this postoperative regime. Thus there is a need for alternative techniques that would eliminate such a regime. The authors review a series of patients who underwent macular hole surgery using silicone oil without any postoperative posturing.
METHODS—A retrospective case note review was performed of patients who had undergone macular hole surgery with silicone oil tamponade. The patients were unable to posture due to chronic illness and had stage 2, 3, or 4 full thickness macular holes. Removal of silicone oil performed with or without cataract surgery was arranged 3 months or more after surgery.
RESULTS—10 eyes of 10 patients underwent surgery. Duration of oil tamponade ranged from 3-9 months. Following oil removal the hole was closed in eight eyes (80%), of which only three showed any improvement in visual acuity (38%) even after cataract extraction. All eyes developed cataract to varying degrees and one eye developed raised intraocular pressure which settled after oil removal. A serious complication, endophthalmitis, occurred in one eye following removal of sutures after cataract extraction.
CONCLUSION—The anatomical results (80%) in this series are in keeping with those reported in other studies using gas tamponade. The visual results are disappointing and less rewarding than those obtained after successful surgery using gas tamponade.

 PMID:11673298

  5. The Intravitreal Autologous Platelet Concentrate Injection as an Adjunct of Vitrectomy for the Treatment of Refractory Macular Holes

    ClinicalTrials.gov

    2014-03-06

    Macular Hole With High Myopia (Spherical Equivalent ≤ -6.0 Diopters) or,; Large Size Macular Hole (Diameter > 600 Microns) or; Recurred or Failed Macular Hole From Previous Surgery; or Chronic Macular Hole (Symptom Duration > 6 Months)

  6. Leber Hereditary Optic Neuropathy Associated with Bilateral Macular Holes

    PubMed Central

    Shimada, Yoshiaki; Horiguchi, Masayuki

    2016-01-01

    ABSTRACT Leber hereditary optic neuropathy (LHON) causes visual loss, predominantly in healthy young men. We recently examined a patient who previously had bilateral macular holes and subsequently developed LHON at 74 years of age. Although his central scotomas were initially attributed to the macular holes, his visual acuity declined following an initial improvement after operative closure of the macular holes; thus, other diagnoses, including LHON, were considered. Furthermore, macular optical coherence tomography (OCT) images remained unchanged in this time. A mitochondrial genetic analysis identified a 11778G→A mutation. From this case, we propose that LHON remains in the differential diagnosis even in older patients, as has previously been reported. PMID:27335507

  7. Spontaneous closure of macular hole following blunt trauma.

    PubMed

    Freitas-Neto, Clovis Arcoverde; Pigosso, Douglas; Pacheco, Katia Delalíbera; Pereira, Viviane Oliveira; Patel, Pranav; Freitas, Luiz Guilherme; Ávila, Marcos Pereira

    2016-01-01

    Ocular trauma can result in macular hole and it can lead to complete loss of central vision. We are reporting a case of traumatic macular hole associated with retinal hemorrhages and choroidal ruptures with spontaneous resolution and total vision recovery. PMID:27433039

  8. Optimal management of idiopathic macular holes

    PubMed Central

    Madi, Haifa A; Masri, Ibrahim; Steel, David H

    2016-01-01

    This review evaluates the current surgical options for the management of idiopathic macular holes (IMHs), including vitrectomy, ocriplasmin (OCP), and expansile gas use, and discusses key background information to inform the choice of treatment. An evidence-based approach to selecting the best treatment option for the individual patient based on IMH characteristics and patient-specific factors is suggested. For holes without vitreomacular attachment (VMA), vitrectomy is the only option with three key surgical variables: whether to peel the inner limiting membrane (ILM), the type of tamponade agent to be used, and the requirement for postoperative face-down posturing. There is a general consensus that ILM peeling improves primary anatomical hole closure rate; however, in small holes (<250 µm), it is uncertain whether peeling is always required. It has been increasingly recognized that long-acting gas and face-down positioning are not always necessary in patients with small- and medium-sized holes, but large (>400 µm) and chronic holes (>1-year history) are usually treated with long-acting gas and posturing. Several studies on posturing and gas choice were carried out in combination with ILM peeling, which may also influence the gas and posturing requirement. Combined phacovitrectomy appears to offer more rapid visual recovery without affecting the long-term outcomes of vitrectomy for IMH. OCP is licensed for use in patients with small- or medium-sized holes and VMA. A greater success rate in using OCP has been reported in smaller holes, but further predictive factors for its success are needed to refine its use. It is important to counsel patients realistically regarding the rates of success with intravitreal OCP and its potential complications. Expansile gas can be considered as a further option in small holes with VMA; however, larger studies are required to provide guidance on its use. PMID:26834454

  9. Optimal management of idiopathic macular holes.

    PubMed

    Madi, Haifa A; Masri, Ibrahim; Steel, David H

    2016-01-01

    This review evaluates the current surgical options for the management of idiopathic macular holes (IMHs), including vitrectomy, ocriplasmin (OCP), and expansile gas use, and discusses key background information to inform the choice of treatment. An evidence-based approach to selecting the best treatment option for the individual patient based on IMH characteristics and patient-specific factors is suggested. For holes without vitreomacular attachment (VMA), vitrectomy is the only option with three key surgical variables: whether to peel the inner limiting membrane (ILM), the type of tamponade agent to be used, and the requirement for postoperative face-down posturing. There is a general consensus that ILM peeling improves primary anatomical hole closure rate; however, in small holes (<250 µm), it is uncertain whether peeling is always required. It has been increasingly recognized that long-acting gas and face-down positioning are not always necessary in patients with small- and medium-sized holes, but large (>400 µm) and chronic holes (>1-year history) are usually treated with long-acting gas and posturing. Several studies on posturing and gas choice were carried out in combination with ILM peeling, which may also influence the gas and posturing requirement. Combined phacovitrectomy appears to offer more rapid visual recovery without affecting the long-term outcomes of vitrectomy for IMH. OCP is licensed for use in patients with small- or medium-sized holes and VMA. A greater success rate in using OCP has been reported in smaller holes, but further predictive factors for its success are needed to refine its use. It is important to counsel patients realistically regarding the rates of success with intravitreal OCP and its potential complications. Expansile gas can be considered as a further option in small holes with VMA; however, larger studies are required to provide guidance on its use.

  10. Laser-induced macular holes demonstrate impaired choroidal perfusion

    NASA Astrophysics Data System (ADS)

    Brown, Jeremiah, Jr.; Allen, Ronald D.; Zwick, Harry; Schuschereba, Steven T.; Lund, David J.; Stuck, Bruce E.

    2003-06-01

    Choroidal perfusion was evaluated following the creation of a laser induced macular hole in a nonhuman primate model. Two Rhesus monkeys underwent macular exposures delivered by a Q-switched Nd:YAG laser. The lesions were evaluated with fluorescein angiography and indocyanine green (ICG) angiography . Each lesion produced vitreous hemorrhage and progressed to a full thickness macular hole. ICG angiography revealed no perfusion of the choriocapillaris beneath the lesion centers. Histopathologic evaluation showed replacement of the choriocapillaris with fibroblasts and connective tissue. Nd:YAG, laser-induced macular holes result in long term impairment of choroidal perfusion at the base of the hole due to choroidal scarring and obliteration of the choriocapillaris.

  11. Macular Hole Formation After Intravitreal Ranibizumab Injection in Wet Age-Related Macular Degeneration

    PubMed Central

    Mukherjee, Chandoshi; Mitra, Arijit; Kumar, N. Ajith; Elsherbiny, Samer; Lip, Peck Lin

    2015-01-01

    Ranibizumab is a monoclonal antibody fragment that inhibits angiogenesis by inhibiting vascular endothelial growth factor A, used as a treatment for patients with wet aged-related macular degeneration (ARMD). Adverse effects from intravitreal Ranibizumab injections are well recognised. Macular hole formation following Ranibizumab injection is a complication that has been recently reported in few case reports. We present a larger case series of five patients, who developed full thickness macular holes (FTMH) after intravitreal Ranibizumab injections for treatment of wet ARMD that we were aware of between 2009 and 2013. PMID:26962382

  12. Inverted Internal Limiting Membrane Flap For Large Traumatic Macular Holes

    PubMed Central

    Abou Shousha, Mohsen Ahmed

    2016-01-01

    Abstract The aim of the study was to assess the role of inverted internal limiting membrane flap as a treatment option for large traumatic macular holes. This is a prospective noncomparative study in which 12 eyes with large traumatic macular holes (basal diameter of 1300–2800 μm) since 3 to 6 months were subjected to standard 23-gauge vitrectomy with removal of the posterior hyaloid, brilliant blue G (BBG)-assisted internal limiting membrane peeling in a circular fashion keeping it attached to the edge of the hole to create a flap. At the end of the surgery, air fluid exchange was done with inversion of the internal limiting membrane flap inside the macular hole using the soft tipped cannula and sulfur hexafluoride 20% as tamponade. The main follow-up measures are the best corrected visual acuity and the optical coherence tomography for 6 to 9 months. All the included eyes had a closed hole from the first week postoperative and along the follow-up period (6–9 months). The best corrected visual acuity improved from 20/2000 to 20/200 with a median of 20/400 preoperatively to 20/400 to 20/50 with a median of 20/100 at the end of follow-up period. Inverted internal limiting membrane flap is a good adjuvant to standard vitrectomy in the management of large traumatic macular holes that led to the 100% closure rate and improvement of best corrected visual acuity. PMID:26817894

  13. Prediction of spontaneous closure of traumatic macular hole with spectral domain optical coherence tomography

    PubMed Central

    Chen, Haoyu; Chen, Weiqi; Zheng, Kangken; Peng, Kun; Xia, Honghe; Zhu, Lei

    2015-01-01

    It has been known that some traumatic macular holes can close spontaneously. However, knowledge about the types of macular hole that can close spontaneously is limited. In this retrospective study, we investigated patients with traumatic macular hole who were followed-up for at least 6 months without any surgical intervention. Clinical data and spectral domain optical coherence tomography (SD-OCT) images were compared between groups with and without macular hole closure. Overall, 27 eyes were included. Spontaneous closure of macular hole was observed in 10 (37.0%) eyes. The holes with spontaneous closure had smaller minimum diameter (244.9 ± 114.4 vs. 523.9 ± 320.0 μm, p = 0.007) and less intraretinal cysts (10% vs. 76.5%, p = 0.001) compared to the holes that did not close spontaneously. The area under the curve of receiver operative characteristic was 0.812 and 0.832 for minimum diameter of macular hole and presence of intraretinal cysts respectively. Multivariate logistic regression showed that the presence of intraretinal cysts was an independent predictive factor for closure of macular holes. The group with spontaneous macular hole closure had a high chance of visual improvement. Our study suggests that the absence of intraretinal cysts on SD-OCT can predict spontaneous closure of traumatic macular hole. PMID:26196460

  14. Early imaging of a macular hole following vitrectomy with primary silicone oil tamponade

    PubMed Central

    Saha, Niladri; Lake, Stewart; Wang, Bob Z

    2011-01-01

    Background To describe the morphology of a macular hole in the early postoperative period following vitrectomy with primary silicone oil tamponade. Methods A case report with optical coherence tomography (OCT) scans prior to surgery, at 20 minutes postoperatively and then at 17 hours postoperatively. Results OCT images of a 73-year-old woman with a stage 3 macular hole were obtained. At 20 minutes postoperatively, there was a reduction in intraretinal cysts and a reduction in macular hole size with elevated-open configuration. At 17 hours postoperatively, complete macular hole closure was noted. Conclusion OCT Images of a macular hole in the early postoperative period have been successfully obtained. Macular holes can close within 24 hours postoperatively and show morphological changes that may be predictive of closure within 20 minutes postoperatively. PMID:22140310

  15. Late Closure of a Stage III Idiopathic Macular Hole after Pars Plana Vitrectomy

    PubMed Central

    Afrashi, Filiz; Öztaş, Zafer; Nalçacı, Serhad

    2015-01-01

    A 57-year-old female presented to our hospital with decreased vision in her right eye. Detailed ocular examination was performed, and a macular hole was detected in the right eye. The presence of a full-thickness stage III macular hole was confirmed with optical coherence tomography (OCT) imaging. Pars plana vitrectomy followed by long-acting gas tamponade (C3F8) was performed as treatment. One month after surgery, clinical examination revealed a persistent macular hole, confirmed by an OCT scan. Although the patient was scheduled for reoperation, the surgery was postponed due to personal reasons of the patient. Surprisingly, after five months, a closure pattern with accompanying epiretinal membrane was observed in the macular hole area. The closure of the macular hole was completed without any further intervention 8 months post-surgery. In cases of unclosed macular hole after the first surgery, if a second surgery cannot be performed, follow-up with OCT recommended due to the possibility of spontaneous closure. However, spontaneous closure of a persistent macular hole following PPV is rare, so early diagnosis and surgical repair of unclosed macular holes must remain the primary goal. PMID:27800248

  16. Value of internal limiting membrane peeling in surgery for idiopathic macular hole and the correlation between function and retinal morphology.

    PubMed

    Christensen, Ulrik Correll

    2009-12-01

    Idiopathic macular hole is characterized by a full thickness anatomic defect in the foveal retina leading to loss of central vision, metamorphopsia and a central scotoma. Classic macular hole surgery consists of vitrectomy, posterior vitreous cortex separation and intraocular gas tamponade, but during the past decade focus has especially been on internal limiting membrane (ILM) peeling as adjuvant therapy for increasing closure rates. With increasing use of ILM peeling and indocyanine green (ICG) staining, which is used for specific visualization of the ILM, concerns about the safety of the procedure have arisen. At present, it is not known whether ICG-assisted ILM peeling potentially reduces the functional outcome after macular hole surgery. The purpose of the present PhD thesis was to examine whether ICG-assisted ILM peeling offers surgical and functional benefit in macular hole surgery. We conducted a randomized clinical trial including 78 pseudophakic patients with idiopathic macular hole stages 2 and 3. Patients were randomly assigned to macular hole surgery consisting of (i) vitrectomy alone without instrumental retinal surface contact (non-peeling), (ii) vitrectomy plus 0.05% isotonic ICG-assisted ILM peeling or (iii) vitrectomy plus 0.15% trypan blue (TB)-assisted ILM peeling. Morphologic and functional outcomes were assessed 3, 6 and 12 months after surgery. The results show that surgery with ILM peeling, for both stages 2 and 3 macular holes, is associated with a significantly higher closure rate than surgery without ILM peeling (95% versus 45%). The overall functional results confirm that surgery for macular hole generally leads to favourable visual results, with two-thirds of eyes regaining reading vision (>or=20/40). Macular hole surgery can be considered a safe procedure with a low incidence of sight-threatening adverse events; the retinal detachment rate was 2.2%. Visual outcomes in eyes with primary hole closure were not significantly different

  17. Inverted internal limiting membrane flap technique for very large macular hole

    PubMed Central

    Khodani, Mitali; Bansal, Pooja; Narayanan, Raja; Chhablani, Jay

    2016-01-01

    AIM To assess the anatomical and visual outcome of idiopathic macular holes greater than 1000 µm using the inverted internal limiting membrane flap technique. METHODS This retrospective case series included 5 eyes of 5 patients with idiopathic macular hole with base diameter greater than 1000 µm who underwent inverted internal limiting membrane flap technique along with standard 23G pars plans vitrectomy with posterior hyaloid detachment and fluid gas exchange with 12%-14% perfluoropropane (C3F8). Preoperative and postoperative visual acuity and spectral domain optical coherence tomography images were evaluated. The main outcome measures were visual outcome and macular hole closure. RESULTS Mean age was 63.2±8.4y with all 5 subjects being females. Mean duration of symptoms was 11±14mo with a mean postoperative follow up of 13.2±13mo. The mean base diameter of the macular holes was 1420±84.8 µm (1280-1480 µm). Type 1 closure was achieved in four out of five patients, while one patient had type 2 closure using the inverted internal limiting membrane (ILM) flap technique. Median baseline BCVA was 0.79 logMAR (Snellen's equivalent 20/120) and median final BCVA 0.6 logMAR (Snellen's equivalent 20/80) with mean visual improvement of approximately three lines improvement. No complications related to surgical procedure were noted. CONCLUSION The inverted internal limiting membrane flap technique may be promising for very large macular holes with high rate of macular closure and good visual outcome. PMID:27588280

  18. Vitrectomy and Microperimetry of an Accidental Macular Hole Caused by Nd:YAG Laser

    PubMed Central

    Chen, Yung-Jen

    2010-01-01

    A 31-year-old man sustained a 1,064-nm Q-switched Nd:YAG laser injury to his left eye. One month after the injury, the fundus and optical coherence tomography (OCT) examination demonstrated a full-thickness macular hole of approximately 820 μm in diameter. After vitrectomy and internal limiting membrane peeling, OCT showed closure of the hole and a marked thinning of the foveal depression. After 12 months of follow-up, his visual acuity improved from 20/60 to 20/20. The MP1-microperimeter demonstrated increased retinal sensitivity in the area of the previous macular hole and its adjacent region and improvement of fixation from a relatively unstable status to a stable status. The macular hole remained closed 24 months postoperatively with the best corrected visual acuity 20/20. Our results suggest that vitrectomy can improve the visual function when a macular hole is caused by Nd:YAG laser injury. The improvement in the visual function includes not only visual acuity but also retinal sensitivity and fixation stability that are obtained by using the MP1-microperimeter. PMID:21103202

  19. Comparison of Ultrahigh- and Standard-Resolution Optical Coherence Tomography for Imaging Macular Hole Pathology and Repair

    PubMed Central

    Ko, Tony H.; Fujimoto, James G.; Duker, Jay S.; Paunescu, Lelia A.; Drexler, Wolfgang; Baumal, Caroline R.; Puliafito, Carmen A.; Reichel, Elias; Rogers, Adam H.; Schuman, Joel S.

    2007-01-01

    Purpose To compare ultrahigh-resolution optical coherence tomography (UHR-OCT) technology to a standard-resolution OCT instrument for the imaging of macular hole pathology and repair; to identify situations where UHR-OCT provides additional information on disease morphology, pathogenesis, and management; and to use UHR-OCT as a baseline for improving the interpretation of the standard-resolution images. Design Observational and interventional case series. Participants Twenty-nine eyes of 24 patients clinically diagnosed with macular hole in at least one eye. Methods A UHR-OCT system has been developed and employed in a tertiary-care ophthalmology clinic. Using a femtosecond laser as the low-coherence light source, this new UHR-OCT system can achieve an unprecedented 3-μm axial resolution for retinal OCT imaging. Comparative imaging was performed with UHR-OCT and standard 10-μm resolution OCT in 29 eyes of 24 patients with various stages of macular holes. Imaging was also performed on a subset of the population before and after macular hole surgery. Main Outcome Measures Ultrahigh- and standard-resolution cross-sectional OCT images of macular hole pathologies. Results Both UHR-OCT and standard-resolution OCT exhibited comparable performance in differentiating various stages of macular holes. The UHR-OCT provided improved imaging of finer intraretinal structures, such as the external limiting membrane and photoreceptor inner segment (IS) and outer segment (OS), and identification of the anatomy of successful surgical repair. The improved resolution of UHR-OCT enabled imaging of previously unidentified changes in photoreceptor morphology associated with macular hole pathology and postoperative repair. Visualization of the junction between the photoreceptor IS and OS was found to be an important indicator of photoreceptor integrity for both standard-resolution and UHR-OCT images. Conclusions Ultrahigh-resolution optical coherence tomography improves the visualization

  20. Partial Thickness Rotator Cuff Tears: Current Concepts

    PubMed Central

    Matthewson, Graeme; Beach, Cara J.; Nelson, Atiba A.; Woodmass, Jarret M.; Ono, Yohei; Boorman, Richard S.; Lo, Ian K. Y.; Thornton, Gail M.

    2015-01-01

    Partial thickness rotator cuff tears are a common cause of pain in the adult shoulder. Despite their high prevalence, the diagnosis and treatment of partial thickness rotator cuff tears remains controversial. While recent studies have helped to elucidate the anatomy and natural history of disease progression, the optimal treatment, both nonoperative and operative, is unclear. Although the advent of arthroscopy has improved the accuracy of the diagnosis of partial thickness rotator cuff tears, the number of surgical techniques used to repair these tears has also increased. While multiple repair techniques have been described, there is currently no significant clinical evidence supporting more complex surgical techniques over standard rotator cuff repair. Further research is required to determine the clinical indications for surgical and nonsurgical management, when formal rotator cuff repair is specifically indicated and when biologic adjunctive therapy may be utilized. PMID:26171251

  1. Effect of Internal Limiting Membrane Abrasion on Retinal Tissues in Macular Holes

    PubMed Central

    Almeida, David R. P.; Chin, Eric K.; Tarantola, Ryan M.; Folk, James C.; Boldt, H. Culver; Skeie, Jessica M.; Mullins, Robert F.; Russell, Stephen R.; Mahajan, Vinit B.

    2015-01-01

    Purpose. The purpose of this study was to identify the structural and histological effects of a Tano diamond-dusted membrane scraper (DDMS) on the retinal surface after internal limiting membrane (ILM) abrasion in macular hole surgery. Methods. Institutional experimental study was performed in 11 eyes. All eyes underwent ILM abrasion in the operating room with a DDMS for macular hole repair as an alternative to traditional ILM peeling. Three human donor eyes underwent an identical procedure in the laboratory. Retinal tissues were removed by ILM abrasion with a DDMS during vitrectomy for macular hole repair and retinal tissues remaining in human donor eyes. Main outcome measures were microscopic and immunohistological characteristics of instrument tip tissues and retinal structure after ILM abrasion. Results. The tips of the Tano DDMS showed evidence of cellular membranes and ILM removal. The retinas showed distinct areas of lamellar ILM removal without penetration of the retinal nerve fiber layer (RNFL). Conclusions. Application of the Tano DDMS instrument is sufficient to remove membranes from the surface of the ILM and layers of the ILM without disruption of the underlying RNFL. Internal limiting membrane abrasion can be a useful and effective alternative to complete ILM removal for macular surgery. PMID:26024069

  2. “Magic Bullet”: Eccentric Macular Hole as a Complication from Dexamethasone Implant Insertion

    PubMed Central

    Sanders, Riley; Olson, Jeffrey

    2016-01-01

    Introduction. Intravitreal drug injections and implants are generally safe but do carry some risk, from both the procedure itself and adverse effects of the medications. We report a case of an eccentric macular hole after dexamethasone implant (Ozurdex®) administration. Ex vitro force testing was performed to evaluate dexamethasone implant injection force. Methods. Five dexamethasone implant (Ozurdex) applicators were placed 16 mm from a force plate and the force of the injected dexamethasone pellet was recorded in Newtons. Four dexamethasone implant applicators were placed 16 mm from a force plate in a basic saline solution and the force of the pellet was recorded. Results. Average maximum force in air was 0.77 N and 0.024 N in a basic saline solution (BSS). Conclusion. We present a case report of an eccentric macular hole after dexamethasone implant administration. We hypothesize a mechanical injury to the retina during insertion caused the macular hole. Force testing done in air demonstrated sufficient force from the pellet injection to cause retinal damage though injections done in BSS showed reduced forces.

  3. [Therapeutic Options in Vitreomacular Traction With or Without a Macular Hole].

    PubMed

    Maier, M; Abraham, S; Frank, C; Lohmann, C P; Feucht, N

    2016-05-01

    Treatment is usually indicated for symptomatic vitreomacular traction (VMT) with or without a full thickness macular hole (FTMH) and without spontaneous resolution. Ultrastructural parameters are evaluated by SD-OCT, in order to classify the vitreoretinal interface and to estimate the success rate of treatment. The resolution rate after therapy with intravitreal Jetrea® (Ocriplasmin) is high (up to 70 %) in patients with symptomatic focal vitreomacular traction (≤ 1500 µm) with or without a macular hole (≤ 250 µm) and with no epiretinal membrane (ERM), but depends on the exact baseline analysis. All other patients with idiopathic traction retinopathy should be treated by minimal invasive pars plana vitrectomy (MIVI). Vitreoretinal surgery effectively removes traction and gives a high closure rate of a full thickness macular hole (FTMH, 90 to 100 %). It is now a very safe procedure with few side effects. Despite a low risk profile (cataract, retinal tear etc.) the indication for surgery needs to take the safety profile into account. Therefore vitrectomy is only indicated in symptomatic patients complaining of blurred vision, VA reduction and metamorphopsia. Vitrectomy is also indicated in patients whose treatment by pharmacologic vitreolysis has failed. PMID:27187883

  4. Idiopathic vitreomacular traction and macular hole: a comprehensive review of pathophysiology, diagnosis, and treatment

    PubMed Central

    Steel, D H W; Lotery, A J

    2013-01-01

    Posterior vitreous detachment (PVD) is a common phenomenon in the aging eye. However, this may be complicated by persistent symptomatic vitreomacular adhesions that exert tractional forces on the macula (vitreomacular traction; VMT). VMT itself may be associated with epiretinal membrane formation and the development of idiopathic macular holes (IMH). Such pathologies may cause visual disturbances, including metamorphopsia, photopsia, blurred vision, and decreased visual acuity, which impact an individual's quality of life. Technologies such as optical coherence tomography allow an increasingly more accurate visualisation of the macular anatomy, including quantification of macular hole characteristics, and this facilitates treatment decision-making. Pars plana vitrectomy remains the primary treatment option for many patients with VMT or IMH; for the latter, peeling of the inner limiting membrane (ILM) of the retina has shown improved outcomes when compared with no ILM peeling. The development of narrow-gauge transconjunctival vitrectomy systems has improved the rate of visual recovery following surgery. Ocriplasmin, by degrading laminin and fibronectin at the vitreoretinal interface, may allow induction of PVD in a non-invasive manner. Indeed, clinical studies have supported its use as an alternative to surgery in certain patient populations. However, further research is still needed with respect to greater understanding of the pathophysiology underlying the development of VMT and IMH. PMID:24108069

  5. [Transmission electronic microscopy of the inner limiting membrane and epiretinal tissue in idiopathic macular hole].

    PubMed

    Synek, S; Pác, L

    2005-03-01

    The authors examined samples of epimacular tissue obtained during the surgeries of the idiopathic macular hole in different stages of the disease by means of transmission electronic microscopy. In the early stages of the disease only the inner limiting membrane with isolated cells on the vitreous side was present, in later ones of the disease the connective tissue membrane was attached. In rare cases of the later stages of the disease they found the presence of the retinal pigment epithelium (RPE). They suppose the RPE plays an important role in the regeneration of the defects of the retina.

  6. A Review of Current Management of Vitreomacular Traction and Macular Hole

    PubMed Central

    García-Layana, Alfredo; García-Arumí, José; Ruiz-Moreno, José M.; Arias-Barquet, Lluís; Cabrera-López, Francisco; Figueroa, Marta S.

    2015-01-01

    The paper presents a review of the sequence of events of posterior vitreous detachment (PVD), vitreomacular adhesion (VMA), vitreomacular traction (VMT), and macular hole (MH) from their pathophysiological aspects, clinical features, diagnostic implications, and current management strategies. A treatment algorithm to be used in clinical practice in patients with VMA, VMT, and MH based on the presence of symptoms, visual acuity, associated epiretinal membrane, and width of the vitreous attachment is presented. Observation, pharmacologic vitreolysis with ocriplasmin, and surgical treatment are positioned as treatment options in the different steps of the therapeutic algorithm, with clear indications of the paths to be followed according to the initial presenting manifestations and the patient's clinical course. PMID:25821592

  7. Wide-field laser ophthalmoscopy for imaging of gas-filled eyes after macular hole surgery

    PubMed Central

    Nakao, Shintaro; Arita, Ryoichi; Sato, Yuki; Enaida, Hiroshi; Ueno, Akifumi; Matsui, Takaaki; Salehi-Had, Hani; Ishibashi, Tatsuro; Sonoda, Koh-hei

    2016-01-01

    Background and objective Existing ophthalmoscopy methods are unable to obtain clear fundus autofluorescence (FAF) images in gas-filled eyes. The purpose of this study was to evaluate the capability of wide-field laser ophthalmoscopy (Optos) in obtaining FAF images in gas-filled eyes for the assessment of macular hole (MH) closure after surgery. Methods This was an interventional case series. Eighteen consecutive patients with unilateral MH underwent vitrectomy with internal limiting membrane peeling and 20% sulfur hexafluoride gas tamponade. FAF images using Optos were recorded preoperatively and postoperatively (days 1, 2, and 7). Results On postoperative days 1, 2, and 7, FAF images were obtained from 11/18 (61.1%), 9/18 (50.0%), and 17/18 eyes (94.4%), respectively, using Optos. The quality of FAF images using Optos was sufficient to determine MH closure in 9/18 (50.0%) of gas-filled eyes postoperatively. Quantitative analysis of FAF images was helpful in determining complete or partial closure of the MH. Conclusion FAF imaging using Optos might be a useful adjunct to optical coherence tomography as a supportive method to guide the release from facedown posturing in some cases of MH.

  8. Wide-field laser ophthalmoscopy for imaging of gas-filled eyes after macular hole surgery

    PubMed Central

    Nakao, Shintaro; Arita, Ryoichi; Sato, Yuki; Enaida, Hiroshi; Ueno, Akifumi; Matsui, Takaaki; Salehi-Had, Hani; Ishibashi, Tatsuro; Sonoda, Koh-hei

    2016-01-01

    Background and objective Existing ophthalmoscopy methods are unable to obtain clear fundus autofluorescence (FAF) images in gas-filled eyes. The purpose of this study was to evaluate the capability of wide-field laser ophthalmoscopy (Optos) in obtaining FAF images in gas-filled eyes for the assessment of macular hole (MH) closure after surgery. Methods This was an interventional case series. Eighteen consecutive patients with unilateral MH underwent vitrectomy with internal limiting membrane peeling and 20% sulfur hexafluoride gas tamponade. FAF images using Optos were recorded preoperatively and postoperatively (days 1, 2, and 7). Results On postoperative days 1, 2, and 7, FAF images were obtained from 11/18 (61.1%), 9/18 (50.0%), and 17/18 eyes (94.4%), respectively, using Optos. The quality of FAF images using Optos was sufficient to determine MH closure in 9/18 (50.0%) of gas-filled eyes postoperatively. Quantitative analysis of FAF images was helpful in determining complete or partial closure of the MH. Conclusion FAF imaging using Optos might be a useful adjunct to optical coherence tomography as a supportive method to guide the release from facedown posturing in some cases of MH. PMID:27601877

  9. Redesigning services for the management of vitreomacular traction and macular hole.

    PubMed

    Amoaku, W; Cackett, P; Tyagi, A; Mahmood, U; Nosek, J; Mennie, G; Rumney, N

    2014-07-01

    Vitreomacular traction (VMT) and VMT with macular hole (MH) are serious conditions, being associated with visual disturbance, for example, metamorphopsia, and diminished visual acuity (VA). Pars plana vitrectomy is the routine treatment for symptomatic VMT and VMT+MH. However, ocriplasmin has demonstrated favourable efficacy and safety in specific patient groups with VMT/MH and is now recommended as a treatment option for certain patients by the National Institute of Health and Care Excellence. This means that services for managing patients with VMT/MH may need to be revised, as patients can now potentially receive treatment earlier in the course of the disease. VMT triage clinics could provide a more efficient way of managing VMT/MH patients. Patient assessment should always include high-definition optical coherence tomography, as this is the most accurate means of assessing abnormalities in the vitreoretinal (VR) interface, and an accurate measurement of best-corrected VA. It has been proposed that patients with VMT+MH be managed as a routine 6-week referral, with the complete patient journey-from initial referral to treatment-taking no longer than 6 months. It is important that patients are entered onto VR surgical lists so that there is no delay if ocriplasmin treatment is unsuccessful. Patients will need appropriate counselling about the expected outcomes and possible side effects of ocriplasmin treatment. One-year follow-up data should be collected by treatment centres in order to evaluate the new VMT service.

  10. Dynamics of the Macular Hole-Silicone Oil Tamponade Interface with Patient Positioning as Imaged by Spectral Domain Optical Coherence Tomography

    PubMed Central

    Oster, Stephen F.; Mojana, Francesca; Bartsch, Dirk-Uwe G.; Goldbaum, Michael; Freeman, William R.

    2010-01-01

    Purpose To evaluate with spectral domain optical coherence tomography (SD-OCT) the relationship between the retina and overlying silicone oil tamponade after macular hole surgery, and to evaluate how this relationship changes with patient positioning. Patients and Methods Retrospective consecutive case series of 10 eyes from 9 patients who underwent macular hole surgery with silicone oil tamponade and subsequent SD-OCT scans. Four of the included eyes were also imaged with patients in face-down posture to determine if the silicone-retina apposition changes with prone positioning. Finally, a single patient was additionally scanned in the lateral and supine positions. Results The posterior surface of the silicone oil bubble was well visualized in all 10 eyes. In the majority of eyes (7/10) the oil tamponade bridged across the macular hole creating a pre-foveal fluid space, but in 3 eyes the silicone oil filled the macular hole and was seen in touch with the underlying foveal depression or retinal pigment epithelium. In 75% of eyes (3/4) the silicone oil-retinal approximation did not vary with face-down position. Supine positioning clearly floated the silicone tamponade anteriorly and off of the retinal surface. Conclusions Silicone oil tamponade can either bridge across macular holes, or in a novel finding, can fill the underlying foveal depression or macular hole space. Generally, the oil position is stable between face-forward and prone SD-OCT images, suggesting that either of these patient positions allows waterproofing of the underlying macular hole. Finally, our images confirm that supine positioning should be avoided post-operatively as it leads to loss of oil-retinal tamponade. PMID:20531144

  11. Full-Thickness Macular Hole Formation after Internal Limiting Membrane Peeling: Beware the “Omega Sign”

    PubMed Central

    2016-01-01

    Purpose. To introduce a clinical sign on spectral domain optical coherence tomography (SDOCT), which may indicate high risk for full-thickness macular hole formation after internal limiting membrane (ILM) peeling. Methods. The preoperative SDOCT images of two patients—one with multilaminar hemorrhage from ruptured retinal artery macroaneurysm and one with serous retinal detachment and severe macular schisis from optic pit maculopathy—who developed full-thickness macular hole (FTMH) after ILM peeling were evaluated retrospectively. Results. On the preoperative SDOCT images of both patients there was a thin bridge of tissue on either side of the foveal center with an outer retinal defect. The photoreceptors were displaced laterally away from the foveal center to create an “omega-” shaped configuration of the remaining tissue. Conclusion. “Omega-” shaped configuration on SDOCT may represent a higher risk of FTMH following ILM peeling. Vitreoretinal surgeons may wish to consider this sign in the process of their surgical decision making. PMID:27747120

  12. Cost-effectiveness of ocriplasmin for the treatment of vitreomacular traction and macular hole

    PubMed Central

    Bennison, Craig; Stephens, Stephanie; Lescrauwaet, Benedicte; Van Hout, Ben; Jackson, Timothy L.

    2016-01-01

    Background If left untreated, vitreomacular traction (VMT) will infrequently improve through spontaneous resolution of vitreomacular adhesion (VMA), and patients remain at risk of further deterioration in vision. The mainstay of treatment for VMT is vitrectomy, an invasive procedure that carries the risk of rare but serious complications and further vision loss. As such, a ‘watch and wait’ approach is often adopted before this surgical intervention is performed. Ocriplasmin (microplasmin) is a potential alternative treatment for patients with symptomatic VMA/VMT that may remove the requirement for vitrectomy. Objective The purpose of this study was to evaluate the cost-effectiveness of ocriplasmin for the treatment of VMT in comparison to standard of care. Study design A cohort-based computer simulation model was developed, capturing three mutually exclusive subgroups: 1) VMT without epiretinal membrane (ERM) or full thickness macular hole (FTMH), 2) VMT with ERM but no FTMH, and 3) VMT with FTMH. Transition probabilities between health states, utilities, and resource utilisation were estimated based on clinical trial results, the literature, and expert opinion. The cost per quality-adjusted life year (QALY) gained was estimated over a lifetime, using UK unit costs and utilities associated with visual acuity, adverse events, metamorphopsia, and surgical interventions. Setting Analyses were conducted from a UK payer perspective. Population Transition probabilities for the model were primarily estimated from patient-level data from the combined Phase 3 MIVI-TRUST trials in patients with symptomatic VMA/VMT, including when associated with a FTMH ≤400 µm. Intervention Ocriplasmin (microplasmin) is a one-time intravitreal injection designed specifically to release the abnormal traction between the macula and the vitreous and thereby treat VMT, as well as macular hole with persistent vitreous attachment. Main outcome measure The main outcome measure of the

  13. Inner Segment Ellipsoid Band and Cone Outer Segment Tips Changes Preceding Macular Hole Development in a Young Patient

    PubMed Central

    Garcia-Aguirre, Gerardo; Schwartz, Shulamit

    2014-01-01

    Purpose. Pathophysiology of macular hole (MH) is not yet well defined but the advances of spectral domain optical coherence tomography (SD-OCT) give us access to further detailed imaging. We report a case with macular inner segment ellipsoid (ISe) band loss and cone outer segment tips (COST) line changes seen in SD-OCT preceding MH appearance in a young patient. Methods. 21-year-old woman presented with a partial central scotoma, metamorphopsia, and a 20/25 vision in her right eye. Past medical history was positive for laser assisted in situ keratomileusis (LASIK) surgery 7 months ago with no complications. Macular SD-OCT showed ISe band loss and COST line elevation. She was followed a month later with visual acuity deteriorating to 20/200 and a full thickness MH. Results. The patient underwent a pars plana vitrectomy with internal limiting membrane peeling. Her visual acuity 2 months later was 20/20. Conclusion. SD-OCT can identify preliminary changes, yet to be described, preceding MH formation. Our patient demonstrated ISe band loss and COST abnormalities on SD-OCT a month prior to MH development. SD-OCT should be considered in young patients with subtle visual symptoms and mild changes in visual acuity that are not readily explained by ophthalmological exam. PMID:25548697

  14. Inner segment ellipsoid band and cone outer segment tips changes preceding macular hole development in a young patient.

    PubMed

    Harasawa, Mariana; Quiroz-Mercado, Hugo; Salcedo-Villanueva, Guillermo; Garcia-Aguirre, Gerardo; Schwartz, Shulamit

    2014-01-01

    Purpose. Pathophysiology of macular hole (MH) is not yet well defined but the advances of spectral domain optical coherence tomography (SD-OCT) give us access to further detailed imaging. We report a case with macular inner segment ellipsoid (ISe) band loss and cone outer segment tips (COST) line changes seen in SD-OCT preceding MH appearance in a young patient. Methods. 21-year-old woman presented with a partial central scotoma, metamorphopsia, and a 20/25 vision in her right eye. Past medical history was positive for laser assisted in situ keratomileusis (LASIK) surgery 7 months ago with no complications. Macular SD-OCT showed ISe band loss and COST line elevation. She was followed a month later with visual acuity deteriorating to 20/200 and a full thickness MH. Results. The patient underwent a pars plana vitrectomy with internal limiting membrane peeling. Her visual acuity 2 months later was 20/20. Conclusion. SD-OCT can identify preliminary changes, yet to be described, preceding MH formation. Our patient demonstrated ISe band loss and COST abnormalities on SD-OCT a month prior to MH development. SD-OCT should be considered in young patients with subtle visual symptoms and mild changes in visual acuity that are not readily explained by ophthalmological exam. PMID:25548697

  15. Relationship between Peeled Internal Limiting Membrane Area and Anatomic Outcomes following Macular Hole Surgery: A Quantitative Analysis.

    PubMed

    Goker, Yasin Sakir; Koc, Mustafa; Yuksel, Kemal; Yazici, Ahmet Taylan; Demir, Abdulvahit; Gunes, Hasan; Ozpinar, Yavuz

    2016-01-01

    Purpose. To quantitatively evaluate the effects of peeled internal limiting membrane (ILM) area and anatomic outcomes following macular hole surgery using spectral domain optical coherence tomography (SD-OCT). Methods. Forty-one eyes in 37 consecutive patients with idiopathic, Gass stage 3-4 macular hole (MH) were enrolled in this retrospective comparative study. All patients were divided into 2 groups according to anatomic success or failure. Basal MH diameter, peeled ILM area, and MH height were calculated using SD-OCT. Other prognostic parameters, including age, stage, preoperative BCVA, and symptom duration were also assessed. Results. Thirty-two cases were classified as anatomic success, and 9 cases were classified as anatomic failure. Peeled ILM area was significantly wider and MH basal diameter was significantly less in the anatomic success group (p = 0.024 and 0.032, resp.). Other parameters did not demonstrate statistical significance. Conclusion. The findings of the present study show that the peeled ILM area can affect the anatomic outcomes of MH surgery. PMID:27413544

  16. Relationship between Peeled Internal Limiting Membrane Area and Anatomic Outcomes following Macular Hole Surgery: A Quantitative Analysis

    PubMed Central

    Goker, Yasin Sakir; Koc, Mustafa; Yuksel, Kemal; Yazici, Ahmet Taylan; Gunes, Hasan; Ozpinar, Yavuz

    2016-01-01

    Purpose. To quantitatively evaluate the effects of peeled internal limiting membrane (ILM) area and anatomic outcomes following macular hole surgery using spectral domain optical coherence tomography (SD-OCT). Methods. Forty-one eyes in 37 consecutive patients with idiopathic, Gass stage 3-4 macular hole (MH) were enrolled in this retrospective comparative study. All patients were divided into 2 groups according to anatomic success or failure. Basal MH diameter, peeled ILM area, and MH height were calculated using SD-OCT. Other prognostic parameters, including age, stage, preoperative BCVA, and symptom duration were also assessed. Results. Thirty-two cases were classified as anatomic success, and 9 cases were classified as anatomic failure. Peeled ILM area was significantly wider and MH basal diameter was significantly less in the anatomic success group (p = 0.024 and 0.032, resp.). Other parameters did not demonstrate statistical significance. Conclusion. The findings of the present study show that the peeled ILM area can affect the anatomic outcomes of MH surgery. PMID:27413544

  17. Keratin dressings speed epithelialization of deep partial-thickness wounds.

    PubMed

    Pechter, Patricia M; Gil, Joel; Valdes, Jose; Tomic-Canic, Marjana; Pastar, Irena; Stojadinovic, Olivera; Kirsner, Robert S; Davis, Stephen C

    2012-01-01

    Keratin gene expression is regarded as a hallmark of epidermal biology. It demarcates the three keratinocyte phenotypes: basal (expressing KRT5 and KRT14), differentiating (expressing KRT1 and KRT10), and activated (wound healing), which is characterized by expression of KRT6, KRT16, and KRT17. Activated keratinocytes are among the first signals of epidermal wound healing. In addition, they are found deregulated in nonhealing chronic wounds. To examine keratins as a potential modality for wound-healing disorders, we evaluated two different keratin dressings, liquid or solid, and assessed their effects of epithelialization and closure using porcine partial-thickness wound-healing model in vivo. We found that both forms of keratin dressings accelerated closure and epithelialization, achieving statistically significant differences on day 5. Evidence suggesting early onset of epithelialization was corroborated further by gene expression analyses revealing induction of KRT6A, KRT16, and KRT17 by day 2 postwounding. The data suggest that keratin dressings may stimulate epithelialization by enhancing the activation of keratinocytes. We conclude that keratin-containing dressings can accelerate wound healing and closure. Further studies are needed to determine the molecular mechanisms of this activation.

  18. Transient Increase of Retinal Nerve Fiber Layer Thickness after Vitrectomy with ILM Peeling for Idiopathic Macular Hole

    PubMed Central

    Sato, Atsuko; Senda, Nami; Fukui, Emi

    2016-01-01

    Purpose. The purpose of this study was to determine the long-term changes in the circumpapillary retinal nerve fiber layer (RNFL) thickness following macular hole surgery with internal limiting membrane (ILM) peeling combined with phacoemulsification. Methods. Thirty-eight eyes of 37 patients who had pars plana vitrectomy (n = 36) between 2010 and 2014 were studied. The average thicknesses of the global and the six sectors of the RNFL were determined before and at 1, 3, 6, 12, and 24 (n = 22) months (M) after the surgery by spectral-domain optical coherent tomography. The postoperative mean RNFL thickness at each time was compared to that before the surgery by paired t-tests. Results. The RNFL of the operated eyes was significantly thicker at 1 month (1 M) and 3 M in all but the inferior-nasal sectors. The significant increase remained until 12 M in the superior-temporal and superior-nasal sectors. In addition, the RNFL was also significantly thicker in the temporal-inferior sector at 12 M based on the findings in 38 eyes. Conclusions. The postoperative RNFL was thicker in all but the nasal-inferior sector for at least 12 M after surgery. This prolonged increase of the RNFL thickness may indicate damage and mild edema of the RNFL. PMID:27803812

  19. TEMPORAL INVERTED INTERNAL LIMITING MEMBRANE FLAP TECHNIQUE FOR A MACULAR HOLE PATIENT UNABLE TO MAINTAIN POSTOPERATIVE PRONE POSITIONING

    PubMed Central

    Tanito, Masaki; Sugihara, Kazunobu; Kodama, Tatsuo; Ohira, Akihiro

    2016-01-01

    Purpose: To report the surgical technique and efficacy of the temporal inverted internal limiting membrane (ILM) flap technique for a patient with an idiopathic macular hole (MH) who is unable to maintain postoperative prone positioning. Methods: Case report. Results: A 73-year-old man with a Stage III MH in his left eye was scheduled to undergo surgery. Owing to his inability to maintain postoperative prone positioning for continuous placement of a transdermal bladder catheter after radical cystoprostatectomy to treat urinary bladder cancer, he underwent pars plana vitrectomy combined with the temporal inverted ILM flap technique and intraocular sulfur hexafluoride gas tamponade. The technique included ILM peeling at a temporal area of the macula to create one 2-disk-diameter semicircular ILM flap and inversion of the ILM flap nasally to cover the MH. Optical coherence tomography showed that MH closure started from the top of the MH just beneath the covered ILM flap; the closure process gradually extended toward the bottom of the MH. The well-aligned fovea recovered in 5 weeks postoperatively. The visual acuity was 20/200 preoperatively and improved to 20/50 postoperatively. Conclusion: The temporal inverted ILM flap technique, a simple surgery to treat MHs, provides scaffolding for retinal gliosis and may facilitate bridge formation between the walls of the MH beneath the flap. The procedure may be a good option to achieve MH closure without postoperative prone positioning. PMID:26674274

  20. Macular degeneration

    MedlinePlus

    ... at the center of the field of vision. Macular degeneration results from a partial breakdown of the insulating ... choroid layer of blood vessels behind the retina. Macular degeneration results in the loss of central vision only.

  1. Efficiency of Microbial Cellulose Dressing in Partial-Thickness Burn Wounds

    PubMed Central

    Muangman, Pornprom; Opasanon, Supaporn; Suwanchot, Supaparn; Thangthed, Orapin

    2011-01-01

    Microbial cellulose is a natural polymer that can hold a quantity of water without any disconformities. Therefore, it is proposed for use as wound dressing material. We report a case of 28% total body surface area partial-thickness flame burn: approximately 4.5% superficial partial-thickness burns on anterior face and 23.5% combined superficial and deep partial-thickness burns on both upper arms and anterior trunk. A microbial cellulose dressing, Nanocell (Thai Nano Cellulose Co Ltd, Bangkok, Thailand), was applied to the face wound only once, without any further dressing change. Progress of healing, until full epithelialization on the face, was observed for 2 weeks. During the treatment period, the patient did not show any irritation or allergic reaction to this new dressing, and wound swab culture showed no evidence of bacteria presence. This innovative material can be an alternative dressing for superficial partial-thickness burn wounds. PMID:24527162

  2. COHORT SAFETY AND EFFICACY STUDY OF SILURON2000 EMULSIFICATION-RESISTANT SILICONE OIL AND F4H5 IN THE TREATMENT OF FULL-THICKNESS MACULAR HOLE

    PubMed Central

    Pinxten, Anne-Marie; Wong, David S.

    2015-01-01

    Purpose: To evaluate safety and efficacy of using Siluron2000 silicone oil in the treatment of full-thickness macular hole by comparing its propensity to emulsify with emulsification of the “gold standard” Siluron5000, and to assess safety and efficacy of F4H5 (perfluorobutylpentane) in removing emulsified oil droplets from the eye. Methods: A single-center, randomized controlled parallel group trial in 72 patients undergoing vitrectomy for treatment of full-thickness macular hole. The study comprises four treatment groups. First, the total patient group was divided into 2 study arms of 36 patients each, receiving either Siluron2000 or Siluron5000 after vitrectomy with a 3-month follow-up after vitrectomy. Second, F4H5 was used during oil removal in half of the patients in each study arm (18 patients within each study arm) with follow-up at 6 weeks after oil removal. Oil droplets were counted within the removed oil; residual emulsification bubbles were quantified using ultrasound imaging. Results: Safety and efficacy of the oils were comparable. Injection and removal time of Siluron2000 oil was significantly less than that of Siluron5000 oil. Patients treated with F4H5 had borderline significantly less emulsification droplets than those not treated with F4H5. Conclusion: Siluron2000 silicone oil seems to be equally safe and effective as Siluron5000 oil but allows for better handling with the potential of reducing procedure time. The application of F4H5 seems to be safe and effective in reducing residual emulsification. PMID:26066703

  3. Successful closure of treatment-naïve, flat edge (Type II), full-thickness macular hole using inverted internal limiting membrane flap technique

    PubMed Central

    Hussain, Nazimul; Hussain, Anjli

    2016-01-01

    Objective The objective of this study was to present the outcome of the internal limiting membrane (ILM) peeling flap technique for a treatment-naïve, flat edge (Type II), full-thickness macular hole (MH). Methods A 52-year-old man presented with complaints of decreased vision and seeing black spot. He was diagnosed to have a flat edge, full-thickness MH, which was confirmed by optical coherence tomography (OCT). He underwent 23G vitrectomy with brilliant blue G-assisted inverted ILM peeling with an inverted flap over the hole followed by fluid gas exchange. Results Postoperative follow-up until 3 months showed successful closure of the MH, which was confirmed by OCT. The best-corrected visual acuity improved from baseline 6/60 to 6/12 at the final follow-up. Conclusion Using the inverted ILM flap technique, a treatment-naïve, flat edge (Type II), full thickness MH achieved successful anatomical and functional outcomes. PMID:27785110

  4. Cystoid Macular Edema in Bietti's Crystalline Retinopathy

    PubMed Central

    2014-01-01

    A 27-year-old man with progressive bilateral visual decline was diagnosed to have Bietti's crystalline dystrophy (BCD). Fluorescein angiography revealed bilateral petaloid type late hyperfluorescence implicating concurrent cystoid macular edema (CME). Optical coherence tomography exhibited cystoid foveal lacunas OU. During the follow-up of six years, intraretinal crystals reduced in amount but CME persisted angiographically and tomographically. CME is among the rare macular features of BCD including subfoveal sensorial detachment, subretinal neovascular membrane, and macular hole. PMID:24949209

  5. Inverted Internal Limiting Membrane Flap Technique for Repair of Large Macular Holes: A Short-term Follow-up of Anatomical and Functional Outcomes

    PubMed Central

    Chen, Zhe; Zhao, Chan; Ye, Jun-Jie; Wang, Xu-Qian; Sui, Rui-Fang

    2016-01-01

    Background: Inverted internal limiting membrane (ILM) flap technique has recently been reported in a limited number of studies as an effective surgical technique for the management of large macular holes (MHs) with fair MH closure rates as well as gains in visual acuity. In the current study, longitudinal changes in multi-focal electroretinogram (mfERG) responses, best-corrected visual acuity (BCVA) and spectral-domain optical coherence tomography (SD-OCT) were evaluated in eyes with large MHs managed by this technique. Methods: A prospective noncontrolled interventional study of eight patients (eight eyes) with large MHs (minimum diameter >400 μm) was conducted. All MHs were treated with pars plana vitrectomy and indocyanine green-assisted inverted ILM flap technique. SD-OCT images were used to assess the anatomical outcomes of surgery while BCVA and mfERG were used to evaluate the functional outcomes during a 3-month follow-up. Results: All patients underwent successful intended manipulation and translocation of the ILM flap without flap dislocation and achieved complete anatomical closure. Partial microstructural reconstruction, demonstrated on SD-OCT as restoration of the external limiting membrane and the ellipsoid zone, was observed in all cases as early as 1 month after surgery. Functionally, as compared to baseline, all patients showed improvements in BCVA and all but one in mfERG response during follow-up. However, Pearson's test revealed no significant correlations between BCVA and mfERG responses of the fovea and of the macular area at each evaluation time point. Conclusions: Inverted ILM flap technique appeares to be a safe and effective approach for the management of large idiopathic MHs with favorable short-term anatomical and functional results. Postoperative reconstruction of the microstructure generally shows good consistency with improvements in both BCVA and mfERG response, of which the latter might be a supplement for the former in

  6. Use of Suprathel® for partial thickness burns in children.

    PubMed

    Highton, Lyndsey; Wallace, Christopher; Shah, Mamta

    2013-02-01

    We evaluated the use of Suprathel(®), a synthetic skin substitute, for partial thickness burns in children. Thirty-three children (20 females, 13 males; mean age 29 months, range 5 months to 11 years) with burns were treated with Suprathel(®). The burns were superficial partial thickness (n=24) or mid-dermal (n=19); the median %TBSA was 4% (range 1-13%). Suprathel(®) was applied after debridement, followed by Vaseline gauze, dry gauze and crepe bandage. The outer dressings were changed every 5-10 days unless clinical problems dictated otherwise. Median healing time was 16 days (range 9-38 days). Ten patients took longer than 21 days to heal, of whom four developed hypertrophic scarring, which was strongly associated with wound infection (p<0.05). Healing time of superficial partial thickness and mid-dermal burns was not significantly different (p=0.494). Suprathel(®) is an effective skin substitute for the treatment of partial thickness burns in children. The majority of burns in children are mixed depth, and Suprathel(®) has the advantage that it may also be used to treat mid-dermal burns. It behaves like a biological dressing but is not animal derived, so is acceptable to all religious and ethnic groups. Further studies to evaluate the efficacy and cost effectiveness of Suprathel(®) compared to other dressings in children are warranted.

  7. Detection of partial-thickness tears in ligaments and tendons by Stokes-polarimetry imaging

    NASA Astrophysics Data System (ADS)

    Kim, Jihoon; John, Raheel; Walsh, Joseph T.

    2008-02-01

    A Stokes polarimetry imaging (SPI) system utilizes an algorithm developed to construct degree of polarization (DoP) image maps from linearly polarized light illumination. Partial-thickness tears of turkey tendons were imaged by the SPI system in order to examine the feasibility of the system to detect partial-thickness rotator cuff tear or general tendon pathology. The rotating incident polarization angle (IPA) for the linearly polarized light provides a way to analyze different tissue types which may be sensitive to IPA variations. Degree of linear polarization (DoLP) images revealed collagen fiber structure, related to partial-thickness tears, better than standard intensity images. DoLP images also revealed structural changes in tears that are related to the tendon load. DoLP images with red-wavelength-filtered incident light may show tears and related organization of collagen fiber structure at a greater depth from the tendon surface. Degree of circular polarization (DoCP) images exhibited well the horizontal fiber orientation that is not parallel to the vertically aligned collagen fibers of the tendon. The SPI system's DOLP images reveal alterations in tendons and ligaments, which have a tissue matrix consisting largely of collagen, better than intensity images. All polarized images showed modulated intensity as the IPA was varied. The optimal detection of the partial-thickness tendon tears at a certain IPA was observed. The SPI system with varying IPA and spectral information can improve the detection of partial-thickness rotator cuff tears by higher visibility of fiber orientations and thereby improve diagnosis and treatment of tendon related injuries.

  8. HydroColloid dressing (Duoderm) for the treatment of superficial and deep partial thickness burns.

    PubMed

    Hermans, M H

    1987-01-01

    HydroColloid Dressing (Duoderm, HCD) is a new kind of dressing, based on the fact that occlusion can provide an optimum wound environment for quick re-epithelialization. Seventy patients with superficial and deep partial thickness burns of up to 7% TBSA were treated with HCD. In 16 patients a second burned area, similar in size and depth of the burn treated with HCD, was treated with human allografts or silversulfadiazine (SSD). Five patients with very small full thickness burns were also treated with HCD. In three patients (4.5%) the treatment with HCD had to be discontinued before total re-epithelialization had occurred, for various reasons. Statistically, HCD provided faster re-epithelialization than allografts or SSD. The cosmetic and functional results were excellent. After six months only one patient was found to have a small area of hypertrophy. In this study HCD was found to be a very good dressing for the treatment of smaller partial thickness burns.

  9. Comparison of the Inverted Internal Limiting Membrane Flap Technique and the Internal Limiting Membrane Peeling for Macular Hole with Retinal Detachment

    PubMed Central

    Matsumura, Takehiro; Takamura, Yoshihiro; Tomomatsu, Takeshi; Arimura, Shogo; Gozawa, Makoto; Kobori, Akira; Inatani, Masaru

    2016-01-01

    Purpose To evaluate the efficacy of the inverted internal limiting membrane (ILM) flap technique in vitrectomy for macular hole (MH) with retinal detachment (RD) compared with vitrectomy using ILM peeling. Methods A retrospective case series study was performed. Twenty-two eyes of 22 patients who underwent vitrectomy for MH with RD and followed-up more than 12 months after the surgery were included in this study. We retrospectively reviewed the medical records of patients who underwent vitrectomy with inverted ILM flap technique or vitrectomy with ILM peeling. Ten patients who had been treated vitrectomy with inverted ILM flap technique, and 12 patients who had been treated vitrectomy with ILM peeling were analyzed. We evaluated changes in best-corrected visual acuity (BCVA) before and after surgery, closing rates of MH, and retinal reattachment rates and compared between both groups. Results MH was closed and RD was reattached postoperatively in 9 eyes (90%) in the inverted ILM flap group. In the ILM peeling group, the MH was closed in 4 eyes (33.3%) and the retinas were reattached in 6 eyes (50%) after surgery. Significant improvement in BCVA after surgery (P = 0.0017) was only found in the inverted ILM flap group. Conclusions Higher rates of closed MH and retinal reattachment, and small but significant improvement in BCVA were found in the inverted ILM flap group. Based on our data, the inverted ILM flap technique may be useful in vitrectomy for MH with RD. PMID:27764184

  10. Myocardial infarct associated with a partial thickness left atrial tear in a dog with mitral insufficiency.

    PubMed

    Sleeper, Meg M; Maczuzak, Meredith E; Bender, Susan J

    2015-09-01

    A 10-year-old male neutered cavalier King Charles Spaniel with a 1-year history of degenerative mitral valve disease presented for dyspnea and severe weakness. He was diagnosed with congestive heart failure, systolic dysfunction, presumptive myocardial infarction and a left atrial thrombus based on thoracic radiographs, electrocardiogram and echocardiographic findings. Clinical signs also suggested right foreleg embolism. The dog was euthanized due to the grave prognosis and a postmortem evaluation was performed. The postmortem examination confirmed myocardial infarction and was thought to be due to embolic showering from the thrombus attached to a partial thickness left atrial endocardial tear. PMID:26263842

  11. [Macular pigments].

    PubMed

    Canovas, Renata; Cypel, Marcela; Farah, Michel Eid; Belfort, Rubens

    2009-01-01

    Lutein and Zeaxanthin are yellow pigments located at the macula. Because of your location macular pigments decrease and filter the amount of blue light that reach photoreceptors, protect the outer retina from oxidative stress and may improve the vision quality. This is a review regarding incorporation mechanism, function and knowledge update. PMID:20098912

  12. Macular Degeneration

    MedlinePlus

    ... common early symptom. Dry AMD happens when the light-sensitive cells in the macula slowly break down. Your gradually lose your central vision. A common early symptom is that straight lines appear crooked. Regular comprehensive eye exams can detect macular degeneration before the disease ...

  13. Treatment of partial thickness burns with Zn-hyaluronan: lessons of a clinical pilot study

    PubMed Central

    Juhász, I.; Zoltán, P.; Erdei, I.

    2012-01-01

    Summary A clinical investigation to determine the effectiveness of Zn-hyaluronan gel for the treatment of partial thickness burns was carried out. 60 patients were enrolled in the study with an average of 3% TBSA burn. Exudation lasted 3 days, no infectious complications were observed. By day 14 the wounds of 52 patients have healed, average complete healing time was 10,5 days. An overall 93,3% healing rate was achieved within the planned observation period. Reduction of spontaneous and movementrelated pain was reduced to less than half of the initial values by day 5,5 and 6,3 respectively. Development of a thin, elastic, well tolerable and protective membrane-like layer was noted. This kept the wounds moist while clean during wound-healing, and was spontaneously shed as epithelisation proceeded. Zn-hyaluronan gel is a novel topical wound care product that has proven to be suitable for the treatment of partial thickness burns. PMID:23233826

  14. US appearance of partial-thickness supraspinatus tendon tears: Application of the string theory. Pictorial essay.

    PubMed

    Guerini, H; Fermand, M; Godefroy, D; Feydy, A; Chevrot, A; Morvan, G; Gault, N; Drapé, J L

    2012-02-01

    The supraspinatus tendon is composed of 5 different layers consisting of intertwining bundles. On a front portion of the tendon, the layers become coated bundles which insert on the trochanter. At the insertion, the superficial or bursal surface of the tendon corresponding to the tendon fibers in contact with the subacromial bursa can be distinguished from the deep surface corresponding to the fibers in contact with the glenohumeral joint. A tendon tear may involve partial or total disruption of the tendon fibers and is called full-thickness tear if it affects the entire tendon, and partial-thickness tear if it involves only part of the tendon. Partial-thickness tears of the supraspinatus tendon include lesions of the superficial, deep and central surface or tendon delamination.A contrast enhanced examination requires injection of contrast agent into the joint (arthrography followed by computed tomography (CT) or magnetic resonance imaging (MRI)) to study the deep surface, and injection into the subacromial bursa (bursography followed by CT) to study the superficial surface. MRI and ultrasound (US) examination allow the study of these different tendon layers without the use of contrast agent (which is not possible at CT).

  15. Optimal treatment of partial thickness burns in children: a systematic review.

    PubMed

    Vloemans, A F P M; Hermans, M H E; van der Wal, M B A; Liebregts, J; Middelkoop, E

    2014-03-01

    A large part of the patient population of a burn centre consists of children, most of whom are younger than four years. The majority of these young children suffer from superficial and deep partial thickness scald burns that may easily deepen to full thickness burns. A proper wound therapy, that prevents infection and ensures a moist wound condition, might prevent the deterioration of the wound. Therefore, we performed a systematic review of wound management and dressing materials to select the best treatment option for children with burns. A search in Medline and Embase revealed 51 articles for a critical appraisal. The articles were divided into randomized controlled trials, cohort studies and a group of case-reports. Total appraisal did not differ much amongst the groups; the level of evidence was highest in the randomized controlled trials and lowest in the case-reports. In 16 out of 34 comparative studies, silver sulfadiazine or a silver sulfadiazine/chlorhexidine-gluconate combination was the standard of wound care treatment. The competitor dressing was Biobrane(®) in six studies and amnion membrane in three. Tulle gauze, or tulle gauze impregnated with an antibacterial addition were the standard of care treatment in seven studies. In general, membranous dressings like Biobrane(®) and amnion membrane performed better than the standard of care on epithelialization rate, length of hospital stay and pain for treatment of partial thickness burns in children. However, hardly any of the studies investigated long-term results like scar formation.

  16. Estimating the time and temperature relationship for causation of deep-partial thickness skin burns.

    PubMed

    Abraham, John P; Plourde, Brian; Vallez, Lauren; Stark, John; Diller, Kenneth R

    2015-12-01

    The objective of this study is to develop and present a simple procedure for evaluating the temperature and exposure-time conditions that lead to causation of a deep-partial thickness burn and the effect that the immediate post-burn thermal environment can have on the process. A computational model has been designed and applied to predict the time required for skin burns to reach a deep-partial thickness level of injury. The model includes multiple tissue layers including the epidermis, dermis, hypodermis, and subcutaneous tissue. Simulated exposure temperatures ranged from 62.8 to 87.8°C (145-190°F). Two scenarios were investigated. The first and worst case scenario was a direct exposure to water (characterized by a large convection coefficient) with the clothing left on the skin following the exposure. A second case consisted of a scald insult followed immediately by the skin being washed with cool water (20°C). For both cases, an Arrhenius injury model was applied whereby the extent and depth of injury were calculated and compared for the different post-burn treatments. In addition, injury values were compared with experiment data from the literature to assess verification of the numerical methodology. It was found that the clinical observations of injury extent agreed with the calculated values. Furthermore, inundation with cool water decreased skin temperatures more quickly than the clothing insulating case and led to a modest decrease in the burn extent.

  17. Macular degeneration (image)

    MedlinePlus

    Macular degeneration is a disease of the retina that affects the macula in the back of the eye. ... see fine details. There are two types of macular degeneration, dry and wet. Dry macular degeneration is more ...

  18. American Macular Degeneration Foundation

    MedlinePlus

    ... to content Contact DONATE Search for: Search Saving sight through research and education American Macular Degeneration Foundation Saving Sight Through Research and Education Menu About Macular Degeneration ...

  19. Macular Diplopia.

    PubMed

    Shippman, Sara; Cohen, Kenneth R; Heiser, Larissa

    2015-01-01

    Maculopathies affect point-to-point foveal correspondence causing diplopia. The effect that the maculopathies have on the interaction of central sensory fusion and peripheral fusion are different than the usual understanding of treatment for diplopia. This paper reviews the pathophysiology of macular diplopia, describes the binocular pathology causing the diplopia, discusses the clinical evaluation, and reviews the present treatments including some newer treatment techniques. PMID:26564922

  20. ERK2 dependent signaling contributes to wound healing after a partial-thickness burn

    SciTech Connect

    Satoh, Yasushi Saitoh, Daizoh; Takeuchi, Atsuya; Ojima, Kenichiro; Kouzu, Keita; Kawakami, Saki; Ito, Masataka; Ishihara, Masayuki; Sato, Shunichi; Takishima, Kunio

    2009-03-27

    Burn healing is a complex physiological process involving multiple cell activities, such as cell proliferation, migration and differentiation. Although extracellular signal-regulated kinases (ERK) have a pivotal role in regulating a variety of cellular responses, little is known about the individual functions of ERK isoform for healing in vivo. This study investigated the role of ERK2 in burn healing. To assess this, Erk2{sup +/-} mice generated by gene targeting were used. The resultant mice exhibited significant delay in re-epithelization of partial-thickness burns in the skin in comparison to wild-type. An in vitro proliferation assay revealed that keratinocytes from Erk2{sup +/-} mice grew significantly slower than those prepared from wild-type. These results highlight the importance of ERK2 in the process of burn healing.

  1. Effect of Topical Platelet-Rich Plasma on Burn Healing After Partial-Thickness Burn Injury

    PubMed Central

    Ozcelik, Umit; Ekici, Yahya; Bircan, Huseyin Yuce; Aydogan, Cem; Turkoglu, Suna; Ozen, Ozlem; Moray, Gokhan; Haberal, Mehmet

    2016-01-01

    Background To investigate the effects of platelet-rich plasma on tissue maturation and burn healing in an experimental partial-thickness burn injury model. Material/Methods Thirty Wistar albino rats were divided into 3 groups of 10 rats each. Group 1 (platelet-rich plasma group) was exposed to burn injury and topical platelet-rich plasma was applied. Group 2 (control group) was exposed to burn injury only. Group 3 (blood donor group) was used as blood donors for platelet-rich plasma. The rats were killed on the seventh day after burn injury. Tissue hydroxyproline levels were measured and histopathologic changes were examined. Results Hydroxyproline levels were significantly higher in the platelet-rich plasma group than in the control group (P=.03). Histopathologically, there was significantly less inflammatory cell infiltration (P=.005) and there were no statistically significant differences between groups in fibroblast development, collagen production, vessel proliferations, or epithelization. Conclusions Platelet-rich plasma seems to partially improve burn healing in this experimental burn injury model. As an initial conclusion, it appears that platelet-rich plasma can be used in humans, although further studies should be performed with this type of treatment. PMID:27262706

  2. Effect of Topical Platelet-Rich Plasma on Burn Healing After Partial-Thickness Burn Injury.

    PubMed

    Ozcelik, Umit; Ekici, Yahya; Bircan, Huseyin Yuce; Aydogan, Cem; Turkoglu, Suna; Ozen, Ozlem; Moray, Gokhan; Haberal, Mehmet

    2016-06-05

    BACKGROUND To investigate the effects of platelet-rich plasma on tissue maturation and burn healing in an experimental partial-thickness burn injury model. MATERIAL AND METHODS Thirty Wistar albino rats were divided into 3 groups of 10 rats each. Group 1 (platelet-rich plasma group) was exposed to burn injury and topical platelet-rich plasma was applied. Group 2 (control group) was exposed to burn injury only. Group 3 (blood donor group) was used as blood donors for platelet-rich plasma. The rats were killed on the seventh day after burn injury. Tissue hydroxyproline levels were measured and histopathologic changes were examined. RESULTS Hydroxyproline levels were significantly higher in the platelet-rich plasma group than in the control group (P=.03). Histopathologically, there was significantly less inflammatory cell infiltration (P=.005) and there were no statistically significant differences between groups in fibroblast development, collagen production, vessel proliferations, or epithelization. CONCLUSIONS Platelet-rich plasma seems to partially improve burn healing in this experimental burn injury model. As an initial conclusion, it appears that platelet-rich plasma can be used in humans, although further studies should be performed with this type of treatment.

  3. A serum amyloid P-binding hydrogel speeds healing of partial thickness wounds in pigs

    PubMed Central

    Gomer, Richard H.; Pilling, Darrell; Kauvar, Lawrence M.; Ellsworth, Stote; Ronkainen, Sanna D.; Roife, David; Davis, Stephen C.

    2010-01-01

    During wound healing, some circulating monocytes enter the wound, differentiate into fibroblast-like cells called fibrocytes, and appear to then further differentiate into myofibroblasts, cells that play a key role in collagen deposition, cytokine release, and wound contraction. The differentiation of monocytes into fibrocytes is inhibited by the serum protein serum amyloid P (SAP). Depleting SAP at a wound site thus might speed wound healing. SAP binds to some types of agarose in the presence of Ca2+. We found that human SAP binds to an agarose with a KD of 7×10−8M and a Bmax of 2.1 μg SAP/mg wet weight agarose. Mixing this agarose 1: 5 w/v with 30 μg/mL human SAP (the average SAP concentration in normal serum) in a buffer containing 2mM Ca2+ reduced the free SAP concentration to ~0.02 μg/mL, well below the concentration that inhibits fibrocyte differentiation. Compared with a hydrogel dressing and a foam dressing, dressings containing this agarose and Ca2+ significantly increased the speed of wound healing in partial thickness wounds in pigs. This suggests that agarose/Ca2+ dressings may be beneficial for wound healing in humans. PMID:19660048

  4. A serum amyloid P-binding hydrogel speeds healing of partial thickness wounds in pigs.

    PubMed

    Gomer, Richard H; Pilling, Darrell; Kauvar, Lawrence M; Ellsworth, Stote; Ronkainen, Sanna D; Roife, David; Davis, Stephen C

    2009-01-01

    During wound healing, some circulating monocytes enter the wound, differentiate into fibroblast-like cells called fibrocytes, and appear to then further differentiate into myofibroblasts, cells that play a key role in collagen deposition, cytokine release, and wound contraction. The differentiation of monocytes into fibrocytes is inhibited by the serum protein serum amyloid P (SAP). Depleting SAP at a wound site thus might speed wound healing. SAP binds to some types of agarose in the presence of Ca(2+). We found that human SAP binds to an agarose with a K(D) of 7 x 10(-8) M and a B(max) of 2.1 microg SAP/mg wet weight agarose. Mixing this agarose 1 : 5 w/v with 30 microg/mL human SAP (the average SAP concentration in normal serum) in a buffer containing 2 mM Ca(2+) reduced the free SAP concentration to approximately 0.02 microg/mL, well below the concentration that inhibits fibrocyte differentiation. Compared with a hydrogel dressing and a foam dressing, dressings containing this agarose and Ca(2+) significantly increased the speed of wound healing in partial thickness wounds in pigs. This suggests that agarose/Ca(2+) dressings may be beneficial for wound healing in humans. PMID:19660048

  5. Comparison of the results of operative and conservative treatment of deep dermal partial-thickness scalds in children.

    PubMed

    Kaźmierski, M; Mańkowski, P; Jankowski, A; Harasymczuk, J

    2007-10-01

    Deep dermal partial-thickness scalds remain one of the most common types of injuries in childhood. Local treatment of those wounds, alternatively described as IIb degree, is still very controversial. Some authors advise conservative treatment of such wounds, pointing to their ability to self-reepithelialise, which is possible but significantly prolonged. Other investigators postulate operative treatment, i.e., tangential necrectomy and split-thickness autologous skin grafting, which may shorten the time of wound healing. Arguments call for contra-arguments, and the problem still seems to be unresolved. There is indeed a lack of acceptable standardisation of the local treatment for deep dermal partial-thickness scalds in the paediatric population. The results of both conservative and operative treatment of 114 children aged between 3 months and 17 years, treated for deep dermal partial-thickness scalds from 1997 to 2004 are presented. The treatment of five groups of patients, divided into groups based on the extent of their burn wounds, is evaluated. The patients were treated by tangential necrectomy and skin grafting, mechanical dermabrasion, Granuflex(R) (Convatec) hydrocolloid dressings, Iruxol Mono(R) (Knoll) enzymatic dressings, or Aquacel Ag(R) (Convatec) hydrofibre dressings with silver ions. A number of parameters of wound healing were analysed. The results of this paper encouraged us to present and discuss a proposition for the standardisation of local treatment of deep dermal partial-thickness burn wounds in the paediatric population, according to the extent of injury.

  6. Transforming growth factor-beta and its effect on reepithelialization of partial-thickness ear wounds in transgenic mice.

    PubMed

    Tredget, Eric B; Demare, Jack; Chandran, Geethan; Tredget, Edward E; Yang, Liju; Ghahary, Aziz

    2005-01-01

    Transforming growth factor-beta (TGF-beta) is known to affect nearly every aspect of wound repair. Many of the effects have been extensively investigated; however, the primary effect of endogenously derived TGF-beta on wound reepithelialization is still not completely understood. To examine this, two types of wounds were made on a transgenic mouse over-expressing TGF-beta1. Full-thickness back wounds were made to compare the wound healing process in the presence of compensatory healing mechanisms. Superficial partial-thickness ear wounds involving only the epidermis were made to determine the effect of TGF-beta on reepithelialization. In the partial-thickness ear wounds, at later time points, the transgenic group had smaller epithelial gaps than the wild-type mice. A greater number of actively proliferating cells, as determined by bromodeoxyuridine incorporation, was also found in the transgenic mice at post-injury day 8. These results show that TGF-beta1 stimulates the rate of reepithelialization at later time points in partial-thickness wounds. However, in the full-thickness back wounds, the transgenic animals exhibited a slower reepithelialization rate at all time points and the number of bromodeoxyuridine-positive cells was fewer. Our findings would suggest that the overexpression of TGF-beta1 speeds the rate of wound closure in partial-thickness wounds by promoting keratinocyte migration. In full-thickness wounds, however, the overexpression of TGF-beta1 slows the rate of wound reepithelialization.

  7. Comparison between cryopreserved and glycerol-preserved allografts in a partial-thickness porcine wound model.

    PubMed

    Yoon, Cheonjae; Lim, Kihwan; Lee, Sungjun; Choi, Yanghwan; Choi, Youngwhan; Lee, Jungsuk

    2016-03-01

    Human skin allografts are one of the best temporary biological coverings for severely burned patients. Cryopreserved (CPA) and glycerol-preserved (GPA) allografts are the most widely used types. This study compared the allograft efficiency of both preservation methods under the same conditions. To simulate actual clinical conditions, we used a porcine wound model. In addition, we evaluated the macroscopic and microscopic scoring of graft performance for each method. Porcine cadaver skin 1 mm thick was obtained from one pig. Cryopreserved skin cell viability was 20.8 %, glycerol-preserved skin was 9.08 %, and fresh skin was 58.6 %. We made ten partial-thickness wounds each in two pigs. The take rates on day 2 were 96.23 and 82.65 % in the GPA and CPA group (both n = 9), respectively. After 1 week, the take rates of both groups were nearly equal. The removal rate at week 5 was 98.87 and 94.41 % in the GPA and CPA group, respectively. On microscopic findings at week 2, inflammation was greater in the CPA group. Other findings such as fibroblast hyperplasia and neovascularization were not significantly different between both groups. At week 5, the score of collagen fiber synthesis was 2.67 ± 0.47 and 2.33 ± 0.47 in the GPA and CPA group, respectively. The epidermal-dermal junction was 2.22 ± 0.79 and 2.00 ± 0.47 in the GPA and CPA group, respectively. These findings suggest that wound healing takes longer in the CPA group. The preservation method of allografts is not a absolute factor in the wound healing process in this wound model.

  8. Macular Degeneration Partnership

    MedlinePlus

    AMD Macular Degeneration Partnership High Contrast Original + Font Size – Home About AMD Dry AMD Wet AMD Experience AMD Living with ... vision on a daily basis. AMD (Age Related Macular Degeneration) Partnership Listen AMD Month Public Service Announcement To ...

  9. Macular Degeneration: An Overview.

    ERIC Educational Resources Information Center

    Chalifoux, L. M.

    1991-01-01

    This article presents information on macular degeneration for professionals helping persons with this disease adjust to their visual loss. It covers types of macular degeneration, the etiology of the disease, and its treatment. Also considered are psychosocial problems and other difficulties that persons with age-related macular degeneration face.…

  10. Interobserver Agreement in the Classification of Partial-Thickness Rotator Cuff Tears Using the Snyder Classification System

    PubMed Central

    Lee, Christopher S.; Davis, Shane M.; Doremus, Brittany; Kouk, Shalen; Stetson, William B.

    2016-01-01

    Background: At present, there is no widely accepted classification system for partial-thickness rotator cuff tears, and as a result, optimal treatment remains controversial. Purpose: To examine the interobserver reliability and accuracy of classifying partial rotator cuff tears using the Snyder classification system. We hypothesized that the Snyder classification would be reproducible with high reliability and accuracy. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: Twenty-seven orthopaedic surgeons reviewed 10 video-recorded shoulder arthroscopies. Each surgeon was provided with a description of the Snyder classification system for partial-thickness rotator cuff tears and was then instructed to use this system to describe each tear. Interrater kappa statistics and percentage agreement between observers were calculated to measure the level of agreement. Surgeon experience as well as fellowship training was evaluated to determine possible correlations. Results: A kappa coefficient of 0.512 indicated moderate reliability between surgeons using the Snyder classification to describe partial-thickness rotator cuff tears. The mean correct score was 80%, which indicated “very good” agreement. There was no correlation between the number of shoulder arthroscopies performed per year and fellowship training and the number of correct scores. Conclusion: The Snyder classification system is reproducible and can be used in future research studies in analyzing the treatment options of partial rotator cuff tears. PMID:27738643

  11. Aqueous humor outflow effects of partial thickness channel created by a femtosecond laser in ex-vivo human eyes

    NASA Astrophysics Data System (ADS)

    Chai, Dongyul; Chaudhary, Gautam; Kurtz, Ron; Juhasz, Tibor

    2007-02-01

    The reduced outflow rate caused by the increased resistance through trabecular meshwork (TM) has been thought to be the main reason for elevated intraocular pressure (IOP). It has been demonstrated that femtosecond laser pulses tuned to 1.7 μm wavelength can create the partial thickness channel in the sclera in ex vivo human eyes [1] and aqueous outflow can be increased by these channels in porcine eyes [2]. It was also shown that the outflow rate is reduced over time in ex vivo human eyes [3]. Therefore, the control experiment without laser treatment at the same condition was conducted and showed that outflow was reduced by 1.5 +/- 0.8 μl/min at 15mmHg and 1.8 +/- 1.0 μl/min at 25mmHg. However, the outflow rate increased by 0.26 μl/min at 15mmHg and 0.15 μl/min at 25mmHg after the partial thickness channel was created, meaning the amount of increased outflow rate might be more than measured considering the outflow reduction in control experiment. We suggest that the femtosecond laser created partial thickness channel can increase the outflow rate and delay the progression of glaucoma.

  12. Ciprofloxacin-loaded keratin hydrogels reduce infection and support healing in a porcine partial-thickness thermal burn.

    PubMed

    Roy, Daniel C; Tomblyn, Seth; Isaac, Kameel M; Kowalczewski, Christine J; Burmeister, David M; Burnett, Luke R; Christy, Robert J

    2016-07-01

    Infection is a leading cause of morbidity and mortality in burn patients. Current therapies include silver-based creams and dressings, which display limited antimicrobial effectiveness and impair healing. The need exists for a topical, point-of-injury antibiotic treatment that provides sustained antimicrobial activity without impeding wound repair. Fitting this description are keratin-based hydrogels, which are fully biocompatible and support the slow-release of antibiotics. Here we develop a porcine model of an infected partial-thickness burn to test the effects of ciprofloxacin-loaded keratin hydrogels on infection and wound healing. Partial-thickness burns were inoculated with either Pseudomonas aeruginosa or Methicillin-resistant Staphylococcus aureus, resulting in infections that persisted for >2 weeks that exceeded 10(5) and 10(6) cfu per gram of tissue, respectively. Compared to silver sulfadiazine, ciprofloxacin-loaded keratin hydrogel treatment significantly reduced the amount of P. aeruginosa and S. aureus in the burn by >99% on days 4, 7, 11, and 15 postinjury. Further, burns treated with ciprofloxacin-loaded keratin hydrogels exhibited similar healing patterns as uninfected burns with regards to reepithelialization, macrophage recruitment, and collagen deposition and remodeling. The ability of keratin hydrogels to deliver antibiotics to fight infection and support healing of partial-thickness burns make them a strong candidate as a first-line burn therapy. PMID:27238250

  13. The "paraglider-wing" sign: an arthroscopic indicator of partial-thickness bursal-surface tears of the supraspinatus tendon.

    PubMed

    Bhatia, Deepak N; van Rooyen, Karin S; de Beer, Joe F

    2007-06-01

    Partial-thickness bursal-surface tears of supraspinatus tendon may be missed on preoperative investigations and can be overlooked at surgery if not specifically sought. The authors describe an arthroscopic sign to detect these tears, when they involve more than half the tendon fibres, from the articular-side of the joint. The "paraglider-wing" sign, visualized during diagnostic glenohumeral arthroscopy, is demonstrated as an upward bulge of the capsulo-tendinous layer through the bursal-surface tear, under pressure of the inflow fluid. A positive sign indicates (1) presence of a partial-thickness bursal-side tear of the supraspinatus tendon, (2) significant depth (stage II or III) of the tear, and (3) the medial extent of the tear along the length of the tendon. A meticulous subacromial bursoscopy and excision of the bursa is then performed to visualize the tear from the subacromial space. Repair of the tear is performed with a double-row suture anchor fixation technique; the medial row of sutures is passed through the intact region of the tendon using the "paraglider-wing" sign as a guide. PMID:17119924

  14. Administration of prednisolone phosphate-liposomes reduces wound contraction in a rat partial-thickness wound model.

    PubMed

    Richters, Cornelia D; Paauw, Nanne J; Mayen, Ilvy; van Bloois, Louis; Metselaer, Josbert M; Storm, Gert; du Pont, John S; Hoekstra, Matthias J; Kreis, Robert W; Kamperdijk, Eduard W A

    2006-01-01

    Macrophages play an important role in the inflammatory phase of wound healing and their activity regulates fibroblasts and keratinocytes. Modulation of macrophage function may result in improvement of the wound healing process. Prednisolone phosphate (PLP) encapsulated into liposomes was administered to partial-thickness wounds in rats. A single dose of 75 microg/kg, applied directly after wounding, resulted in up to a 30% reduction of wound contraction at 28 days after wounding. This effect could not be achieved in the group that was administered free PLP or liposomes containing phosphate-buffered saline to the wound. The number of myofibroblasts was up to 50% lower in wounds treated with the liposomal PLP at 4 days after wounding. The number of macrophages present in the wounds was not statistically different between groups. Most probably, the production of cytokines and growth factors by macrophages is altered after phagocytosing the liposomes, resulting in reduced wound contraction. PMID:17014673

  15. X-82 to Treat Age-related Macular Degeneration

    ClinicalTrials.gov

    2016-08-16

    Age-Related Macular Degeneration (AMD); Macular Degeneration; Exudative Age-related Macular Degeneration; AMD; Macular Degeneration, Age-related, 10; Eye Diseases; Retinal Degeneration; Retinal Diseases

  16. Prevention of peritendinous adhesions using a hyaluronan-derived hydrogel film following partial-thickness flexor tendon injury.

    PubMed

    Liu, Yanchun; Skardal, Aleksander; Shu, Xiao Zheng; Prestwich, Glenn D

    2008-04-01

    Peritendinous adhesions are an important complication of flexor tendon injury. Three hyaluronan (HA)-derived biomaterials were evaluated for the reduction of peritendinous adhesions following partial-thickness tendon injury in rabbits. Rabbits (n = 24) were divided into three groups (n = 8 per group), which were used for gross evaluation, histologic assessment, or biomechanical testing. The fourth and third toes from both hindpaws of each rabbit were randomly assigned to one of four treatments: (i) untreated control, (ii) Seprafilm, (iii) Carbylan-SX in situ crosslinked hydrogel, and (iv) preformed Carbylan-SX film. Rabbits were sacrificed at 3 weeks postsurgery and evaluated anatomically, histologically, and mechanically. All materials used reduced adhesions relative to untreated controls for all three evaluations. Both the gross anatomic and histologic results revealed that Carbylan-SX film was statistically superior to Seprafilm and Carbylan-SX gel in preventing tendon adhesion formation. In biomechanical tests, the Carbylan-SX film-treated hindpaws required the least force to pull the tendon from the sheath. This force was statistically indistinguishable from that required to extrude an unoperated tendon (n = 8). Carbylan-SX gel was less effective than Carbylan-SX film but superior to Seprafilm for all evaluations. A crosslinked HA-derived film promoted healing of a flexor tendon injury without the formation of fibrosis at 3 weeks postoperatively.

  17. A liposome hydrogel with polyvinyl-pyrrolidone iodine in the local treatment of partial-thickness burn wounds.

    PubMed

    Homann, Heinz-Herbert; Rosbach, Oliver; Moll, Wiebke; Vogt, Peter Maria; Germann, Guenter; Hopp, Michael; Langer-Brauburger, Birgit; Reimer, Karen; Steinau, Hans-Ulrich

    2007-10-01

    Local treatment of burn injuries with conventional anti-infective preparations does not provide the moist environment that promotes fast wound healing. In a randomized controlled trial the effects of liposome polyvinyl-pyrrolidone-iodine (PVP-I) hydrogel, a novel formulation of PVP-I in a liposome hydrogel with high water-binding capacity, were investigated in 43 patients with partial-thickness burn wounds in an intraindividual comparison with a conventional silver-sulfadiazine cream. Treatment with liposome PVP-I hydrogel resulted in significantly faster complete healing of the burn wounds compared with silver-sulfadiazine cream (9.9 +/- 4.5 days versus 11.3 +/- 4.9; P < 0.015). The cosmetic result (smoothness, elasticity, appearance) was rated as excellent for 37.0% of study wounds with liposome PVP-I hydrogel compared with 13.0% of wounds treated with silver-sulfadiazine cream. Local tolerability was good; handling and change of dressing were rated as easy. Local treatment with liposome PVP-I hydrogel thus provides fast wound healing with a favorable cosmetic result.

  18. A liposome hydrogel with polyvinyl-pyrrolidone iodine in the local treatment of partial-thickness burn wounds.

    PubMed

    Homann, Heinz-Herbert; Rosbach, Oliver; Moll, Wiebke; Vogt, Peter Maria; Germann, Guenter; Hopp, Michael; Langer-Brauburger, Birgit; Reimer, Karen; Steinau, Hans-Ulrich

    2007-10-01

    Local treatment of burn injuries with conventional anti-infective preparations does not provide the moist environment that promotes fast wound healing. In a randomized controlled trial the effects of liposome polyvinyl-pyrrolidone-iodine (PVP-I) hydrogel, a novel formulation of PVP-I in a liposome hydrogel with high water-binding capacity, were investigated in 43 patients with partial-thickness burn wounds in an intraindividual comparison with a conventional silver-sulfadiazine cream. Treatment with liposome PVP-I hydrogel resulted in significantly faster complete healing of the burn wounds compared with silver-sulfadiazine cream (9.9 +/- 4.5 days versus 11.3 +/- 4.9; P < 0.015). The cosmetic result (smoothness, elasticity, appearance) was rated as excellent for 37.0% of study wounds with liposome PVP-I hydrogel compared with 13.0% of wounds treated with silver-sulfadiazine cream. Local tolerability was good; handling and change of dressing were rated as easy. Local treatment with liposome PVP-I hydrogel thus provides fast wound healing with a favorable cosmetic result. PMID:17901735

  19. [Functional characteristics of macular telangiectasia type 2].

    PubMed

    Heeren, T F C; Krüger, E; Holz, F G; Charbel Issa, P

    2014-09-01

    The first symptoms of macular telangiectasia type 2 usually occur between 50 and 70 years of age. Functional alterations topographically correspond to the morphological changes. Characteristic paracentral scotomata due to focal photoreceptor atrophy can be detected using microperimetry. The predominant paracentral functional loss may cause reading difficulties despite visual acuity in the range between 20/20 and 20/50. Visual acuity around 20/200 may occur once the paracentral photoreceptor atrophy extends centrally, or due to the development of a macular hole or a secondary neovascular membrane. Progression of functional loss can often only be detected by mapping scotoma size or occurrence using microperimetry, while visual acuity may remain unchanged. PMID:25204528

  20. Occult Macular Dystrophy

    PubMed Central

    Sayman Muslubaş, Işıl; Arf, Serra; Hocaoğlu, Mümin; Özdemir, Hakan; Karaçorlu, Murat

    2016-01-01

    Occult macular dystrophy is an inherited macular dystrophy characterized by a progressive decline of bilateral visual acuity with normal fundus appearance, fluorescein angiogram and full-field electroretinogram. This case report presents a 20-year-old female patient with bilateral progressive decline of visual acuity for six years. Her visual acuity was 3-4/10 in both eyes. Anterior segment and fundus examination, fluorescein angiogram and full-field electroretinogram were normal. She could read all Ishihara pseudoisochromatic plates. Fundus autofluorescence imaging was normal. There was a mild central hyporeflectance on fundus infrared reflectance imaging in both eyes. Reduced foveal thickness and alterations of the photoreceptor inner and outer segment junction were observed by optical coherence tomography in both eyes. Central scotoma was also found by microperimetry and reduced central response was revealed by multifocal electroretinogram in both eyes. These findings are consistent with the clinical characteristics of occult macular dystrophy. PMID:27800268

  1. Diabetic Macular Edema

    NASA Astrophysics Data System (ADS)

    Lobo, Conceição; Pires, Isabel; Cunha-Vaz, José

    The optical coherence tomography (OCT), a noninvasive and noncontact diagnostic method, was introduced in 1995 for imaging macular diseases. In diabetic macular edema (DME), OCT scans show hyporeflectivity, due to intraretinal and/or subretinal fluid accumulation, related to inner and/or outer blood-retinal barrier breakdown. OCT tomograms may also reveal the presence of hard exudates, as hyperreflective spots with a shadow, in the outer retinal layers, among others. In conclusion, OCT is a particularly valuable diagnostic tool in DME, helpful both in the diagnosis and follow-up procedure.

  2. Efficacy of a bio-electric dressing in healing deep, partial-thickness wounds using a porcine model .

    PubMed

    Harding, Andrew C; Gil, Joel; Valdes, Jose; Solis, Michael; Davis, Stephen C

    2012-09-01

    Numerous physical modalities have been used in attempts to augment the healing process, including ultrasound, low- energy light therapy, and electrical stimulation (ES). ES has been shown to benefit tissue repair in a variety of wound types, but variations in study designs, administration, and parameters render its application in clinical practice somewhat unconventional. A dressing was designed to generate an electric potential of 0.6 V to 0.7 V in the presence of moisture, thereby delivering a sustained micro-current without the need for an external power source. The purpose of this study was to examine the effects of this bio-electric dressing (BED) on deep, partial-thickness wounds using six female specific pathogen-free animals and a well established porcine model for wound healing. Wounds (10 mm x 7 mm x 0.5 mm) were created in paravertebral and thoracic areas of these animals using a specialized electrokeratome and covered with the active polyester BED and a polyurethane film dressing (n = 30) (treatment) or an inactive polyester and film dressing (n = 30). Using an epidermal migration assay, wounds were assessed daily from day 4 through day 8 post-wounding. Differences in the proportion of wounds healed were statistically significant (P <0.001) on days 5 and 6 post-wounding. These results show BED is more effective than a control dressing treatment with moisture-retentive dressings in this animal model. Controlled clinical studies are warranted to elucidate the potential clinical implications of this treatment modality.

  3. Clinical evaluation comparing the efficacy of aquacel ag hydrofiber dressing versus petrolatum gauze with antibiotic ointment in partial-thickness burns in a pediatric burn center.

    PubMed

    Saba, Salim Charles; Tsai, Roger; Glat, Paul

    2009-01-01

    We conducted this Institutional Review Board-approved retrospective study to compare Aquacel Ag Hydrofiber dressing (Aquacel Ag) to a standard dressing for the treatment of partial thickness burns in children. We used the St. Christopher's Hospital burn center registry to identify 20 pediatric patients who had sustained partial thickness burns over a 10-month period. Ten of these patients had been treated with Aquacel Ag Hydrofiber dressing and 10 were treated with conventional Xeroflo gauze with Bacitracin Zinc ointment, the institutional standard of care for nonoperative partial-thickness burn wounds. Inclusion criteria included anyone with partial-thickness burns below the age of 18 years and in excellent baseline health. Exclusion criteria included inhalation injury, presence of full-thickness burns necessitating surgical debridement, cellulitic, or infected wounds, and percentage total body surface area involvement greater than 40%. Outcomes measured for the Aquacel Ag versus the Xeroflo gauze with Bacitracin Zinc ointment group included hospital length of stay (2.4 vs. 9.6 days), total number of in-house dressing changes (2.7 vs. 17.1), pain on a 10-point scale associated with dressing changes (6.4 vs. 8.2), total number of intravenous narcotic administrations (2.3 vs. 14.4), nursing time adjusted for percentage total body surface area (1.9 vs. 3.5 min), time to wound reepithelialization (10.3 vs. 16.3 days), and patient primary caregiver satisfaction score using a 4-point scale--with four delineating maximum satisfaction (3.8 vs. 1.8). Aquacel Ag proved to be a safe and effective means of treating partial thickness burns with a significant reduction in nursing time and patient pain involved with dressing changes.

  4. What Is Age-Related Macular Degeneration?

    MedlinePlus

    ... Degeneration Diagnosis: How is AMD diagnosed? Macular Degeneration Treatment: How is AMD Treated? Macular ... macular degeneration (AMD) is a deterioration or breakdown of the eye's macula. The macula is a small area in the ...

  5. Sustainable antimicrobial effect of silver sulfadiazine-loaded nanosheets on infection in a mouse model of partial-thickness burn injury.

    PubMed

    Ito, Keisuke; Saito, Akihiro; Fujie, Toshinori; Nishiwaki, Keisuke; Miyazaki, Hiromi; Kinoshita, Manabu; Saitoh, Daizoh; Ohtsubo, Shinya; Takeoka, Shinji

    2015-09-01

    Partial-thickness burn injury has the potential for reepithelialization and heals within 3weeks. If the wound is infected by bacteria before reepithelization, however, the depth of disruption increases and the lesion easily progresses to the full-thickness dermal layers. In the treatment of partial-thickness burn injury, it is important to prevent the wound area from bacterial infection with an antimicrobial dressing. Here, we have tested the antimicrobial properties of polymeric ultra-thin films composed of poly(lactic acid) (termed "PLA nanosheets"), which have high flexibility, adhesive strength and transparency, and silver sulfadiazine (AgSD), which exhibits antimicrobial efficacy. The AgSD-loaded nanosheet released Ag(+) for more than 3days, and exerted antimicrobial efficacy against methicillin-resistant Staphylococcus aureus (MRSA) in an in vitro Kirby-Bauer test. By contrast, a cell viability assay indicated that the dose of AgSD used in the PLA nanosheets did not show significant cytotoxicity toward fibroblasts. In vivo evaluation using a mouse model of infection in a partial-thickness burn wound demonstrated that the nanosheet significantly reduced the number of MRSA bacteria on the lesion (more than 10(5)-fold) and suppressed the inflammatory reaction, thereby preventing a protracted wound healing process.

  6. [Pathopshysiological mechanisms in macular edema].

    PubMed

    Turlea, Cristian; Zolog, Ileana; Blăjan, Codruta; Roşca, C; Turlea, Magdalena; Munteanu, Mihnea; Boruga, Ovidiu

    2014-01-01

    The treatment of diabetic macular edema has known a fast development in the last 5 years where the transition from laser monotherapy to intravitreal pharmacotherapy is becoming standard practice. Intravitreal injections therapy is in a continuous development with promising positive results. The use of intratvitreal devices in the treatment of macular edema of vascular cause has become a viable alternative also in treating diabetic macular edema. Several clinical studies have revealed the superiority of intravitreal treatment versus laser monotherapy. This article is evaluating and reviewing present and future treatments used to combat diabetic macular edema. [corrected].

  7. An unusual complication of blunt ocular trauma: A horseshoe-shaped macular tear with spontaneous closure

    PubMed Central

    Karaca, Umut; Durukan, Hakan A; Mumcuoglu, Tarkan; Erdurman, Cuneyt; Hurmeric, Volkan

    2014-01-01

    A case of horseshoe-shaped macular tear after blunt trauma with the course of the tear and the relevant findings obtained by spectral-domain optical coherence tomography (SD-OCT) is described. A 21-year-old man who had suffered blunt trauma 5 days previously visited our clinic complaining of vision loss in his left eye. Ophthalmic examination and SD-OCT images revealed a horseshoe-shaped macular tear. A month later at the second visit, the macular tear was found to have spontaneously closed. There have been many cases reported previously of the spontaneous closure of traumatic macular holes. A horseshoe-shaped macular tear is an atypical clinical presentation. However, the mechanism of spontaneous closure is hypothetically as same as that for a macular hole. High-resolution images and three-dimensional maps taken with SD-OCT can provide more details on macular diseases and are more useful than time-domain OCT images. PMID:24817754

  8. Macular injury resulting from a high-powered tank laser telemetry device.

    PubMed

    Durukan, Ali Hakan; Gokce, G; Guven, S; Koylu, T; Erdurman, F C

    2015-12-01

    A high-powered laser is an essential part of a modern military rangefinder; however, this paper presents three cases with macular injury resulting from a high-powered tank laser telemetry device. All injuries occurred when another user deliberately pointed the telemetry target unit at the patient's eyes. The devastating effect of this high-powered laser resulted in a permanent foveal scar in the second patient and a macular hole formation in the third patient. This report emphasises that education plays a primary role in preventing accidental laser injuries. Using general guidelines and safety regulations will prevent accidental macular injuries. PMID:25525204

  9. Achondroplasia and Macular Coloboma

    PubMed Central

    Ahoor, M. H.; Amizadeh, Y.; Sorkhabi, R.

    2015-01-01

    Achondroplasia is an autosomal dominant congenital disorder of enchondral ossification. It is clinically characterized by low stature, craniofacial deformity, and vertebral malformation. Associated ophthalmic features include telecanthus, exotropia, angle anomalies, and cone-rod dystrophy. A 24-year-old male presented with decreased vision bilaterally and typical achondroplasia. The best corrected visual acuity was 20/70 in both eyes. Anterior segment examination was normal. Fundus examination revealed a well-demarcated circular paramacular lesion in both eyes. As macular coloboma and achondroplasia are developmental disorders, the funduscopic examination is required in patients with achondroplasia. PMID:26692730

  10. Evidence of healing of partial-thickness rotator cuff tears following arthroscopic augmentation with a collagen implant: a 2-year MRI follow-up

    PubMed Central

    Bokor, Desmond John; Sonnabend, David; Deady, Luke; Cass, Ben; Young, Allan; Van Kampen, Craig; Arnoczky, Steven

    2016-01-01

    Summary Background partial-thickness rotator cuff tears frequently enlarge due to increased local strain and often progress to full-thickness tears. Studies suggest the addition of new tendinous tissue to injured cuff tendons would significantly decrease peak strain, possibly protecting against tear progression. The aim of this study was to assess the ability of a highly-porous collagen implant to induce new tissue formation and limit tear progression when placed on the bursal surface of partial-thickness cuff tears. Methods following arthroscopic subacromial decompression, the implant was attached to the bursal surface of the supraspinatus tendon in a prospective series of 13 consecutive patients with intermediate – (3–6 mm) to high-grade (>6 mm) partial – thickness cuff tears (5 articular, 3 bursal, 5 intra-substance). Tendon thickness, defect size, and tendon quality were evaluated using magnetic resonance imaging (MRI) preoperatively and at 3, 6, 12, and 24 months postoperatively. Clinical outcomes were assessed using the Constant and American Shoulder and Elbow Society scores at the same preoperative and follow-up times. All 13 patients completed all follow-up exams (mean length of follow-up 27.0 months, range 23.3–32.0); no patients were lost to follow-up. Results the implant induced significant new tissue formation in all patients by 3 months (mean increase in tendon thickness 2.2 ± 0.26 mm). This tissue matured over time and became radiologically indistinguishable from the underlying tendon. The partial-thickness cuff tears showed consistent filling of the defects, with complete healing in 7 patients at 12 months, and a progressive improvement in tendon quality in the remaining patients. No tear progression was observed by MRI in any of the patients at 24 months. All clinical scores improved significantly over time. At 24 months, 12 of 13 patients (92%) had satisfactory or better results. Conclusions the results of this clinical study demonstrated

  11. The efficacy of recombinant human activated protein C (rhAPC) vs antithrombin III (at III) vs heparin, in the healing process of partial-thickness burns: a comparative study

    PubMed Central

    Kritikos, O.; Tsagarakis, M.; Tsoutsos, D.; Kittas, C.; Gorgoulis, V.; Papalois, A.; Giannopoulos, A.; Kakiopoulos, G.; Papadopoulos, O.

    2012-01-01

    Summary This is an experimental study regarding the positive effect of recombinant human activated protein C (rhAPC) in the healing process of partial-thickness burns, in comparison to antithrombin III and heparin. On a porcine model we induced superficial partial-thickness and deep partial-thickness burns and performed intravenous administration of the elements of study during the first 48 h. The progress of the condition of the injured tissues was evaluated by histopathological examination at specific time intervals. The results showed an improved healing response of the specimens treated with rhAPC compared to those treated with antithrombin III, heparin, and placebo. PMID:23233823

  12. A prospective randomized trial comparing silver sulfadiazine cream with a water-soluble polyantimicrobial gel in partial-thickness burn wounds.

    PubMed

    Black, Jonathan S; Drake, David B

    2015-01-01

    The lipid base of silver sulfadiazine (SSD) makes removal of the product painful for the patient and difficult for the physician to accurately assess particularly in partial-thickness burn injuries. As an alternative, a water-soluble antimicrobial gel is used at the University of Virginia. We present a prospective, randomized comparison of these two therapies using pain with dressing changes and time to perform dressing changes as our primary endpoints. Adult inpatients with partial-thickness burn wounds were randomized to begin therapy with either SSD cream or the water-soluble burn wound gel (BWG), and then therapies were alternated daily. Pain assessments, time to complete dressing care, total narcotic medication administered, and the number of personnel required for dressing changes were recorded. Eight patients were enrolled resulting in 13 pairs (26 points) of data comparison between the two therapies. Four of the eight enrolled patients (50%) refused to continue receiving SSD because of pain associated with dressing changes and voluntarily withdrew from the study. The amount of time to perform dressing changes was an average of 79 nurse-minutes longer for SSD. A 6.08 greater morphine equivalent was delivered to those having BWG removed.A water-soluble polyantimicrobial gel was superior to SSD in the parameters measured as exhibited by our patient dropout rate and differential time to perform dressing care. Limiting the time to perform dressing care will reduce the cumulative pain experience, improve patient satisfaction, and reduce the resources to deliver care.

  13. High-Grade Articular, Bursal, and Intratendinous Partial-Thickness Rotator Cuff Tears: A Retrospective Study Comparing Functional Outcomes After Completion and Repair.

    PubMed

    Donohue, Nicholas K; Nickel, Brian T; Grindel, Steven I

    2016-01-01

    We conducted a study to assess the impact of tear location on functional outcomes in high-grade partial-thickness rotator cuff tears (PTRCTs) after arthroscopic completion and repair. Retrospectively, we evaluated the preoperative and postoperative findings of 60 patients who underwent arthroscopic completion and repair of Ellman grade 3 partial-thickness tears of the supraspinatus. The 60 patients were grouped by tear subtype (20 articular, 20 bursal, 20 intratendinous) as identified by preoperative imaging and confirmed at time of surgery. After surgery, the 3 subtypes showed similar significant (P < .001) improvements in American Shoulder and Elbow Surgeons scores (articular, 46.9, 85.1; bursal, 44.3, 80.3; intratendinous, 43.6, 86.1), Constant scores (articular, 54.3, 79.4; bursal, 49.9, 75.0; intratendinous, 56.8, 80.9), and visual analog scale scores (articular, 5.1, 1.2; bursal, 5.8, 1.6; intratendinous, 6.0, 1.2). Our study findings validate use of the current algorithm for Ellman grade 3 PTRCTs of the supraspinatus and advocate their completion and repair, regardless of tear location. PMID:27552462

  14. The Effect of Amnion-Derived Cellular Cytokine Solution on the Epithelialization of Partial-Thickness Donor Site Wounds in Normal and Streptozotocin-Induced Diabetic Swine

    PubMed Central

    Bergmann, Juri; Hackl, Florian; Koyama, Taro; Aflaki, Pejman; Smith, Charlotte A.; Robson, Martin C.; Eriksson, Elof

    2009-01-01

    Objective: The purpose of this study was to determine whether amnion-derived cellular cytokine solution (ACCS) could improve the quality of epithelialization and accelerate closure of dermatome-created partial-thickness wounds in normal and streptozotocin-induced diabetic pigs. Methods: Dermatome-created partial-thickness wounds were sealed with wound chambers in healthy and diabetic pigs and were injected with ACCS. Wound fluid was exchanged daily for total protein concentration, and biopsies were taken on days 6, 8, 10, and 12. Epithelialization, thickness of epidermis, number of epidermal cell layers, and rete ridges were evaluated. Results: The macroscopic appearance of the wounds and speed of healing was similar in all groups at each time point. All wounds were healed by day 6. The epidermis was thicker in the ACCS-treated diabetic wounds than in the controls (140.6 μm vs 82.7 μm on day 12 in diabetic pigs). There were more cell layers (13 vs 7.7) in ACCS-treated diabetic pigs on day 12. The number of rete ridges per 2.5 mm was greater on day 12 in the ACCS-treated diabetic wounds (13 vs 8). There was also a significant increase in the number of rete ridges in ACCS-treated nondiabetic pigs but no difference in epidermal thickness or number of cell layers. Conclusion: In diabetic pigs, we found a significantly thicker epidermis and more cell layers and rete ridges in the ACCS-treated wounds. Healthy pigs showed more rete ridges but no difference in thickness of epidermis or number of cell layers on day 12. PMID:19936023

  15. Histomorphometric analysis of early epithelialization and dermal changes in mid-partial-thickness burn wounds in humans treated with porcine small intestinal submucosa and silver-containing hydrofiber.

    PubMed

    Salgado, Rosa M; Bravo, Leonardo; García, Mario; Melchor, Juan M; Krötzsch, Edgar

    2014-01-01

    The objective of this study was to determine the healing rates of mid-partial-thickness burns treated with a porcine intestinal submucosa (SIS) vs. silver-containing cellulose hydrofiber (AgH) dressings. This was done by comparing healing response of burn wounds treated with SIS vs that of burns treated with AgH dressings. Five patients with mid-partial-thickness burns ≤10% of body surface were treated simultaneously, but in different areas, with SIS and AgH dressings; full-thickness biopsies were taken at days 0 and 7. Tissues treated with SIS presented higher epithelial maturation index (6.2 ± 0.84 vs. 3.2 ± 3.28; [mean ± standard deviation], P = .029), better orientation and differentiation of epithelial cells, as well as an appropriate basal lamina structure, collagen deposition, and higher transforming growth factor-β3 expression (7.4 ± 8.1 vs. 2.1 ± 2.6; P = .055) than tissues treated with AgH dressings. Importantly, after the treatment SIS was not integrated in healed tissues. After 3 months of treatment, SIS produced a lower score according to Vancouver Scar Scale (3.6 ± 2.6 vs. 7.2 ± 2.5, P = .025).The submucosa dressing does not simply act as scaffolding for the wound, it provides stimulation in the healing area, probably via growth factors initially present in SIS or matrikines derived from its digestion in the wound site. In conclusion, the present study demonstrated that biological matrices favor the wound-healing process.

  16. Repair versus shaving of partial-thickness articular-sided tears of the upper subscapularis tendon. A prospective randomized controlled trial

    PubMed Central

    RANDELLI, PIETRO; ARRIGONI, PAOLO; ALIPRANDI, ALBERTO; SDAO, SILVANA; RAGONE, VINCENZA; D’AMBROSI, RICCARDO; RANDELLI, FILIPPO; CABITZA, PAOLO; BANFI, GIUSEPPE

    2015-01-01

    Purpose the purpose of this study was to evaluate whether treating partial-thickness articular-sided tears of the upper subscapularis (SSC) tendon with a dedicated suture anchor would result in an internal rotation strength improvement compared with simple shaving of the SSC tendon and footprint. Methods twenty-six patients with a limited SSC tendon tear (equal or inferior to the most superior centimeter) in association with a posterosuperior cuff lesion were prospectively randomized to two treatments: repair with a dedicated suture anchor versus shaving of the tendon and footprint. The patients also underwent long head of the biceps (LHB) treatment and posterosuperior cuff tear repair. In each patient the following parameters were measured both preoperatively and at a minimum follow-up of 2.5 years: strength in internal rotation in the bear-hug testing position (using a digital tensiometer), DASH score and Constant scores. MRI assessment of tendon healing was performed at the final follow-up. Results twenty of the 26 patients (76%) were reviewed after a mean follow-up time of 42 months: 11 patients had undergone SSC tendon repair and nine simple shaving. At final follow-up no significant differences were found between the repaired and shaving group in strength in internal rotation (9.5 ± 3.8 kg versus 10.3±5.4 kg; p=0.7). The DASH score and Constant score also failed to show significant differences between the two groups. Furthermore, no significant difference in SSC tendon healing rate was observed on MRI evaluation. Conclusions partial-thickness articular-sided tear of the upper SSC tendon in association with a posterosuperior rotator cuff repair and LHB treatment, when limited to the superior centimeter of the SSC tendon, shows a comparable performance in terms of strength in internal rotation either after simple shaving or a tendon-to-bone repair. Level of evidence Level II, prospective comparative study. PMID:26889466

  17. Scanning laser tomography Z profile signal width as an objective index of macular retinal thickening

    PubMed Central

    Hudson, C.; Flanagan, J.; Turner, G.; McLeod, D.

    1998-01-01

    AIMS—(i) To evaluate the relation between retinal thickness and the Z profile signal width of a scanning laser tomographer in selected patients exhibiting clinically manifest and circumscribed macular retinal thickening; (ii) to compare the Z profile signal width values of a group of age similar normal subjects with those of the patients with macular retinal thickening; and (iii) to present the methodology underlying the Z profile signal width derivation.
METHODS—Three patients with the following conditions were selected: widespread diabetic macular oedema; localised diabetic macular oedema; and macular hole. The patients were selected because they exhibited clinically manifest and circumscribed macular retinal thickening. Patients underwent fundus photography and a clinical examination which included fundus biomicroscopy. Fourteen age similar normal subjects were also assessed. The Heidelberg retina tomograph (HRT) was utilised to acquire seven topographic images of each macula. Z profile signal width data were analysed using custom software. Signal width was measured at 50% of the maximum intensity.
RESULTS—For each patient with macular retinal thickening, Z profile signal width analysis (after normalisation to reduce the influence of variation in reflectance intensity between successive images) revealed a significant (p<0.0001) localised increase of signal width which agreed with the HRT topographic analysis of retinal height, and also the clinical assessment of retinal thickness. The mean normalised Z profile signal width for the normal subjects (assessed over the whole image) ranged from 0.278 (SD 0.039) to 0.444 (0.063); these values compared with those obtained from patients in areas of macular retinal thickening of 0.761 (0.224) to 0.953 (0.194). Z profile signal width test-retest data for the patient with localised diabetic macular oedema were plus or minus 0.159 which compared with a mean signal width value of 0.761.

  18. Macular posterior pigmentary incontinence: its relation to macular amyloidosis and notalgia paresthetica.

    PubMed

    Westermark, P; Ridderström, E; Vahlquist, A

    1996-07-01

    Patients with clinical features of dorsal macular amyloidosis but without subepidermal amyloid deposits were followed for 2-11 years. The clinical appearance was fairly stable during this period of time, with little tendency of healing. Only 2 of the patients developed typical macular amyloidosis during the follow-up. It is concluded that a condition strongly resembling macular amyloidosis but without amyloid is an entity, and the designation "macular posterior pigmentary incontinence" is proposed. The relationship between macular posterior pigmentary incontinence and the two conditions macular amyloidosis and notalgia paresthetica is discussed. PMID:8869690

  19. Age-Related Macular Degeneration.

    PubMed

    Mehta, Sonia

    2015-09-01

    Age-related macular degeneration (AMD) is the leading cause of vision loss in the elderly. AMD is diagnosed based on characteristic retinal findings in individuals older than 50. Early detection and treatment are critical in increasing the likelihood of retaining good and functional vision.

  20. Arthroscopic Repair of Articular Surface Partial-Thickness Rotator Cuff Tears: Transtendon Technique versus Repair after Completion of the Tear—A Meta-Analysis

    PubMed Central

    Woodmass, Jarret M.; Bois, Aaron J.; Boorman, Richard S.; Thornton, Gail M.

    2016-01-01

    Articular surface partial-thickness rotator cuff tears (PTRCTs) are commonly repaired using two different surgical techniques: transtendon repair or repair after completion of the tear. Although a number of studies have demonstrated excellent clinical outcomes, it is unclear which technique may provide superior clinical outcomes and tendon healing. The purpose was to evaluate and compare the clinical outcomes following arthroscopic repair of articular surface PTRCT using a transtendon technique or completion of the tear. A systematic review of the literature was performed following PRISMA guidelines and checklist. The objective outcome measures evaluated in this study were the Constant Score, American Shoulder and Elbow Surgeons score, Visual Analogue Scale, physical examination, and complications. Three studies met our criteria. All were prospective randomized comparative studies with level II evidence and published from 2012 to 2013. A total of 182 shoulders (mean age 53.7 years; mean follow-up 40.5 months) were analyzed as part of this study. Both procedures provided excellent clinical outcomes with no significant difference in Constant Score and other measures between the procedures. Both procedures demonstrated improved clinical outcomes. However, there were no significant differences between each technique. Further studies are required to determine the long-term outcome of each technique. PMID:27462471

  1. Effect of red and near-infrared wavelengths on low-level laser (light) therapy-induced healing of partial-thickness dermal abrasion in mice.

    PubMed

    Gupta, Asheesh; Dai, Tianhong; Hamblin, Michael R

    2014-01-01

    Low-level laser (light) therapy (LLLT) promotes wound healing, reduces pain and inflammation, and prevents tissue death. Studies have explored the effects of various radiant exposures on the effect of LLLT; however, studies of wavelength dependency in in vivo models are less common. In the present study, the healing effects of LLLT mediated by different wavelengths of light in the red and near-infrared (NIR) wavelength regions (635, 730, 810, and 980 nm) delivered at constant fluence (4 J/cm(2)) and fluence rate (10 mW/cm(2)) were evaluated in a mouse model of partial-thickness dermal abrasion. Wavelengths of 635 and 810 nm were found to be effective in promoting the healing of dermal abrasions. However, treatment using 730- and 980-nm wavelengths showed no sign of stimulated healing. Healing was maximally augmented in mice treated with an 810-nm wavelength, as evidenced by significant wound area reduction (p < 0.05), enhanced collagen accumulation, and complete re-epithelialization as compared to other wavelengths and non-illuminated controls. Significant acceleration of re-epithelialization and cellular proliferation revealed by immunofluorescence staining for cytokeratin-14 and proliferating cell nuclear antigen (p < 0.05) was evident in the 810-nm wavelength compared with other groups. Photobiomodulation mediated by red (635 nm) and NIR (810 nm) light suggests that the biological response of the wound tissue depends on the wavelength employed. The effectiveness of 810-nm wavelength agrees with previous publications and, together with the partial effectiveness of 635 nm and the ineffectiveness of 730 and 980 nm wavelengths, can be explained by the absorption spectrum of cytochrome c oxidase, the candidate mitochondrial chromophore in LLLT.

  2. Effect of red and near-infrared wavelengths on low-level laser (light) therapy-induced healing of partial-thickness dermal abrasion in mice.

    PubMed

    Gupta, Asheesh; Dai, Tianhong; Hamblin, Michael R

    2014-01-01

    Low-level laser (light) therapy (LLLT) promotes wound healing, reduces pain and inflammation, and prevents tissue death. Studies have explored the effects of various radiant exposures on the effect of LLLT; however, studies of wavelength dependency in in vivo models are less common. In the present study, the healing effects of LLLT mediated by different wavelengths of light in the red and near-infrared (NIR) wavelength regions (635, 730, 810, and 980 nm) delivered at constant fluence (4 J/cm(2)) and fluence rate (10 mW/cm(2)) were evaluated in a mouse model of partial-thickness dermal abrasion. Wavelengths of 635 and 810 nm were found to be effective in promoting the healing of dermal abrasions. However, treatment using 730- and 980-nm wavelengths showed no sign of stimulated healing. Healing was maximally augmented in mice treated with an 810-nm wavelength, as evidenced by significant wound area reduction (p < 0.05), enhanced collagen accumulation, and complete re-epithelialization as compared to other wavelengths and non-illuminated controls. Significant acceleration of re-epithelialization and cellular proliferation revealed by immunofluorescence staining for cytokeratin-14 and proliferating cell nuclear antigen (p < 0.05) was evident in the 810-nm wavelength compared with other groups. Photobiomodulation mediated by red (635 nm) and NIR (810 nm) light suggests that the biological response of the wound tissue depends on the wavelength employed. The effectiveness of 810-nm wavelength agrees with previous publications and, together with the partial effectiveness of 635 nm and the ineffectiveness of 730 and 980 nm wavelengths, can be explained by the absorption spectrum of cytochrome c oxidase, the candidate mitochondrial chromophore in LLLT. PMID:23619627

  3. [Therapeutic approach in persistent diabetic macular edema].

    PubMed

    Brănişteanu, Daniel; Moraru, Andreea

    2014-01-01

    Terminology of persistent diabetic macular edema has been initially reserved to cases unresponsive to conventional laser photocoagulation according to ETDRS criteria. While knowledge about pathophysiology of macular edema evolved and new drugs became available, the terminology of persistent diabetic macular edema expanded to include resistance to most current therapies. The purpose of this paper is to review medical and surgical options in the treatment of such difficult cases according to literature data and personal experience.

  4. Association of age-related macular degeneration and reticular macular disease with cardiovascular disease.

    PubMed

    Rastogi, Neelesh; Smith, R Theodore

    2016-01-01

    Age-related macular degeneration is the leading cause of adult blindness in the developed world. Thus, major endeavors to understand the risk factors and pathogenesis of this disease have been undertaken. Reticular macular disease is a proposed subtype of age-related macular degeneration correlating histologically with subretinal drusenoid deposits located between the retinal pigment epithelium and the inner segment ellipsoid zone. Reticular lesions are more prevalent in females and in older age groups and are associated with a higher mortality rate. Risk factors for developing age-related macular degeneration include hypertension, smoking, and angina. Several genes related to increased risk for age-related macular degeneration and reticular macular disease are also associated with cardiovascular disease. Better understanding of the clinical and genetic risk factors for age-related macular degeneration and reticular macular disease has led to the hypothesis that these eye diseases are systemic. A systemic origin may help to explain why reticular disease is diagnosed more frequently in females as males suffer cardiovascular mortality at an earlier age, before the age of diagnosis of reticular macular disease and age-related macular degeneration.

  5. Macular edema. A complication of diabetic retinopathy.

    PubMed

    Ferris, F L; Patz, A

    1984-05-01

    Diabetic macular edema is the leading cause of decreased vision from diabetic retinopathy. This decreased vision is caused by an increase in extracellular fluid within the retina distorting the retinal architecture and frequently taking on a pattern of cystoid macular edema. This fluid accumulates within the retina because of the breakdown of the barriers within the retinal blood vessels and possibly the pigment epithelium. Diabetic macular edema tends to be a chronic disorder. Although spontaneous recovery is not an uncommon occurrence, over one-half of diabetics with macular edema will lose two or more lines of visual acuity within two years. The most promising treatment for diabetic macular edema has been photocoagulation. It is recommended that in all patients with diabetic macular edema attempts be made to normalize elevated blood glucose, decrease elevated blood pressure, and improve cardiac or renal status. Reduction of serum lipids by diet or pharmacologic means is an unproven treatment at this time. The Early Treatment Diabetic Retinopathy Study hopefully will provide more definitive information as to whether photocoagulation is effective in various subgroups of patients with diabetic macular edema.

  6. [Age-related macular degeneration].

    PubMed

    Garcia Layana, A

    1998-01-01

    Age-related macular degeneration (ARMD) is the leading cause of blindness in the occidental world. Patients suffering this process have an important reduction on their quality of life being handicapped to read, to write, to recognise faces of their friends, or even to watch the television. One of the main problems of that disease is the absence of an effective treatment able to revert the process. Laser treatment is only useful in a limited number of patients, and even in these cases recurrent lesions are frequent. These facts and the progressive ageing of our society establish the ARMD as one of the biggest aim of medical investigations for the next century, and currently is focus of attention in the most industrialised countries. One of the most promising pieces of research is focused in the investigation of the risk factors associated with the age-related macular degeneration, in order to achieve a prophylactic treatment avoiding its appearance. Diet elements such as fat ingestion or reduced antioxidant intakes are being investigated as some of these factors, what open a new possibility for a prophylactic treatment. Finally, research is looking for new therapeutic modalities such as selective radiotherapy in order to improve or maintain the vision of these patients.

  7. Hypotrichosis with juvenile macular dystrophy: Portuguese case.

    PubMed

    Elfatoiki, Fatima Zahra; Cordoliani, Florance; Pascal Regane, Pascal; Afforitit-Demoge, Aude

    2016-01-01

    Hypotrichosis with juvenile macular dystrophy is a rare congenital disease mainly found in the Druze population of Northern Israel. This disorder is caused by the CDH3 mutation encoding P-cadherin, which is expressed in retinal pigment epithelium and hair follicles. An 11-year-old girl who was born to related Portuguese parents, had hypotrichosis since birth and macular dystrophy diagnosed at age 5. Fundus examination and fluorescein angiography revealed located macular pigmentary abnormalities. No molecular analysis was done. A fundus examination should be considered mandatory in the assessment of congenital hypotrichosis. PMID:27617529

  8. Advances in the management of macular degeneration

    PubMed Central

    2014-01-01

    Current management of age-related macular degeneration (AMD) can be divided into two categories: first, anti-vasoendothelial growth factor (anti-VEGF) injection for wet macular degeneration; second, anti-oxidant vitamins for dry macular degeneration. New therapies are being developed for both of these diseases using novel technologies and different modes of administration. The hope is that some of these therapies will achieve significant improvement to current management and prevent future loss of vision in this devastating eye condition. PMID:24860651

  9. Diode laser photocoagulation for diabetic macular oedema.

    PubMed Central

    Ulbig, M W; McHugh, D A; Hamilton, A M

    1995-01-01

    AIMS--This study aimed to investigate whether diode laser irradiation, which is poorly absorbed by haemoglobin, can induce closure of leaking retinal microvascular lesions in the treatment of diabetic macular oedema. METHODS--Thirty three eyes with clinically significant diabetic macular oedema were treated with a diode laser. Fundus evaluation before and after treatment included visual acuity, stereoscopic biomicroscopy, colour photographs, and fluorescein angiography. RESULTS--At a mean period of review of 6 months macular oedema had completely or partially resolved in 27 eyes. Visual acuity improved in three, deteriorated in one, and was unchanged in 29 eyes. CONCLUSION--Preliminary data suggest that diode laser therapy induces closure of leaking retinal microaneurysms and is effective in the treatment of diabetic macular oedema. Images PMID:7742274

  10. Genetics Home Reference: vitelliform macular dystrophy

    MedlinePlus

    ... faces. Vitelliform macular dystrophy causes a fatty yellow pigment (lipofuscin) to build up in cells underlying the ... structures in these cells that contain light-sensing pigments. It is unclear why PRPH2 mutations affect only ...

  11. Treatment of partial thickness burns of the hand with the preshaped, semipermeable Procel Burn Cover: results of a multicentre study in the burn centres of Berlin, Duisburg and Munich.

    PubMed

    Jostkleigrewe, F; Brandt, K A; Flechsig, G; Bruck, J C; Henckel von Donnersmarck, G; Mühlbauer, W

    1995-06-01

    The results of a prospective clinical study conducted in three German burn centres are reported. The subject of the evaluation was to show the effectiveness of a new, preshaped, semipermeable burn dressing that is resistant to fluids and bacteria but highly permeable to vapour. The dressing was used in conjunction with 1 per cent silver sulphadiazine cream in treating partial thickness burns of the hand. In 49 patients, 72 partial thickness burned hands were treated. The application proved to be very easy. The time for a dressing change was short (5-10 min). The duration of treatment was 13 days on average. Complications due to infections did not occur. Because of the semipermeable properties of the dressing material, skin macerations occurred in only a few instances (13 per cent) as a result of inappropriate cream application or extremely high exudation rates, and these did not adversely affect the healing process. Patients achieved the ability to perform activities of daily living early with positive results for the patients, the physician and the nursing team.

  12. Acute serous macular detachment and cystoid macular edema after uncomplicated phacoemulsification using standard dose subconjunctival cefuroxime.

    PubMed

    Kontos, Andreas; Mitry, Danny; Althauser, Susanne; Jain, Saurabh

    2014-09-01

    Acute toxic serous macular detachment after cataract surgery is very rare, and has been described previously with the use of high concentrations of intra-cameral cefuroxime. We report a case of serous macular detachment and cystoid macular edema 1 day after uncomplicated phacoemulsification using standard dose subconjunctival cefuroxime at the end of surgery. Our case demonstrates that subconjunctival cefuroxime may cause retinal toxicity in a similar fashion to intra-cameral cefuroxime, possibly due to entry of the drug into the anterior chamber through the section or trans-scleral absorption. To our knowledge, this is the first report of this complication with subconjunctival administration of cefuroxime.

  13. Simulating vision with and without macular disease.

    PubMed

    Marmor, David J; Marmor, Michael F

    2010-01-01

    Conventional photographs do not show how, at any moment of visual fixation, neural vision is clear only in the foveal center. We have developed new computer simulations to show both normal vision and vision with macular disease. These simulations show the nature of momentary vision for life tasks such as reading, facial recognition, and walking in the street. They also dramatically show the impact of macular disease (with scotomas and visual distortion), as there is no surrounding region of clarity. We hope these images will be instructive to both physicians and patients.

  14. Growth factors in porcine full and partial thickness burn repair. Differing targets and effects of keratinocyte growth factor, platelet-derived growth factor-BB, epidermal growth factor, and neu differentiation factor.

    PubMed Central

    Danilenko, D. M.; Ring, B. D.; Tarpley, J. E.; Morris, B.; Van, G. Y.; Morawiecki, A.; Callahan, W.; Goldenberg, M.; Hershenson, S.; Pierce, G. F.

    1995-01-01

    The topical application of recombinant growth factors such as epidermal growth factor, platelet-derived growth factor-BB homodimer (rPDGF-BB), keratinocyte growth factor (rKGF), and neu differentiation factor has resulted in significant acceleration of healing in several animal models of wound repair. In this study, we established highly reproducible and quantifiable full and deep partial thickness porcine burn models in which burns were escharectomized 4 or 5 days postburn and covered with an occlusive dressing to replicate the standard treatment in human burn patients. We then applied these growth factors to assess their efficacy on several parameters of wound repair: extracellular matrix and granulation tissue production, percent reepithelialization, and new epithelial area. In full thickness burns, only rPDGF-BB and the combination of rPDGF-BB and rKGF induced significant changes in burn repair. rPDGF-BB induced marked extracellular matrix and granulation tissue production (P = 0.013) such that the burn defect was filled within several days of escharectomy, but had no effect on new epithelial area or reepithelialization. The combination of rPDGF-BB and rKGF in full thickness burns resulted in a highly significant increase in extracellular matrix and granulation tissue area (P = 0.0009) and a significant increase in new epithelial area (P = 0.007), but had no effect on reepithelialization. In deep partial thickness burns, rKGF induced the most consistent changes. Daily application of rKGF induced a highly significant increase in new epithelial area (P < 0.0001) but induced only a modest increase in reepithelialization (83.7% rKGF-treated versus 70.2% control; P = 0.016) 12 days postburn. rKGF also doubled the number of fully reepithelialized burns (P = 0.02) at 13 days postburn, at least partially because of marked stimulation of both epidermal and follicular proliferation as assessed by proliferating cell nuclear antigen expression. In situ hybridization for

  15. Assessment of Macular Function during Vitrectomy: New Approach Using Intraoperative Focal Macular Electroretinograms

    PubMed Central

    Matsumoto, Celso Soiti; Shinoda, Kei; Terauchi, Gaku; Matsumoto, Harue; Mizota, Atsushi; Miyake, Yozo

    2015-01-01

    Purpose To describe a new technique to record focal macular electroretinograms (FMERGs) during vitrectomy to assess macular function. Methods Intraoperative FMERGs (iFMERGs) were recorded in ten patients (10 eyes) who undergo vitrectomy. iFMERGs were elicited by focal macular stimulation. The stimulus light was directed to the macular area through a 25 gauge (25G) glass fiber optic bundle. Background light was delivered through a dual chandelier-type light fiber probe. Focal macular responses elicited with combinations of stimulus and background luminances were analyzed. Results A stimulus luminance that was approximately 1.75 log units brighter than the background light was able to elicit focal macular responses that were not contaminated by stray light responses. Thus, a stimulus luminance of 160 cd/m2 delivered on a background of 3 cd/m2 elicited iFMEGs from only the stimulated area. This combination of stimulus and background luminances did not elicit a response when the stimulus was projected onto the optic nerve head. The iFMERGs elicited by a 10° stimulus with a duration of 100 ms and an interstimulus interval of 150 ms consisted of an a-, b-, and d-waves, the oscillatory potentials, and the photopic negative response (PhNR). Conclusions Focal ERGs with all components can be recorded from the macula and other retinal areas during vitreous surgery. This new technique will allow surgeons to assess the function of focal areas of the retina intraoperatively. PMID:26658489

  16. Depression in Age-Related Macular Degeneration

    ERIC Educational Resources Information Center

    Casten, Robin; Rovner, Barry

    2008-01-01

    Age-related macular degeneration (AMD) is a major cause of disability in the elderly, substantially degrades the quality of their lives, and is a risk factor for depression. Rates of depression in AMD are substantially greater than those found in the general population of older people, and are on par with those of other chronic and disabling…

  17. Driving and Age-Related Macular Degeneration

    ERIC Educational Resources Information Center

    Owsley, Cynthia; McGwin, Gerald, Jr.

    2008-01-01

    This article reviews the research literature on driving and age-related macular degeneration, which is motivated by the link between driving and the quality of life of older adults and their increased collision rate. It addresses the risk of crashes, driving performance, driving difficulty, self-regulation, and interventions to enhance, safety,…

  18. Macular Amyloidosis and Epstein-Barr Virus

    PubMed Central

    Nahidi, Yalda; Tayyebi Meibodi, Naser; Meshkat, Zahra; Nazeri, Narges

    2016-01-01

    Background. Amyloidosis is extracellular precipitation of eosinophilic hyaline material of self-origin with special staining features and fibrillar ultrastructure. Macular amyloidosis is limited to the skin, and several factors have been proposed for its pathogenesis. Detection of Epstein-Barr virus (EBV) DNA in this lesion suggests that this virus can play a role in pathogenesis of this disease. Objective. EBV DNA detection was done on 30 skin samples with a diagnosis of macular amyloidosis and 31 healthy skin samples in the margin of removed melanocytic nevi by using PCR. Results. In patients positive for beta-globin gene in PCR, BLLF1 gene of EBV virus was positive in 23 patients (8 patients in case and 15 patients in the control group). There was no significant difference in presence of EBV DNA between macular amyloidosis (3.8%) and control (23.8%) groups (P = 0.08). Conclusion. The findings of this study showed that EBV is not involved in pathogenesis of macular amyloidosis. PMID:26981113

  19. Progressive macular hypomelanosis: an overview.

    PubMed

    Relyveld, Germaine N; Menke, Henk E; Westerhof, Wiete

    2007-01-01

    Progressive macular hypomelanosis (PMH) is a common skin disorder that is often misdiagnosed. Various authors have written about similar skin disorders, referring to them by different names, but we believe that all these similar disorders are part of the same entity.PMH is characterized by ill-defined nummular, non-scaly hypopigmented spots on the trunk, often confluent in and around the midline, and rarely extending to the proximal extremities and neck/head region. There is no itch, pain, or preceding inflammation. PMH has a worldwide distribution; however, it is more often identified in Black people living in or originating from tropical countries. It is also more often seen in young females. The natural history of PMH is stable disease or perhaps slow progression over decades, with spontaneous disappearance after mid-life. Extensive pityriasis alba is probably identical with PMH and we suggest discontinuation of use of the former term on the grounds that extensive pityriasis alba is histologically and clinically different from classical pityriasis alba, which is basically an eczematous type of disorder.PMH is characterized histologically by diminished pigment in the epidermis and a normal-looking dermis. Electron microscopy shows a shift from large melanosomes in normal-looking skin to small aggregated, membrane-bound melanosomes in hypopigmented skin. PMH should be differentiated from other disorders with hypopigmentation on the trunk such as pityriasis versicolor. We propose that Propionibacterium acnes bacteria living in hair follicles are the cause of PMH as a result of production of a hypothetical depigmenting factor. This hypothesis is based on: (i) the presence of a red follicular fluorescence in the hypopigmented spots and the absence of this phenomenon in normal skin when examined under a Wood's light in a dark room; (ii) cultivation of P. acnes from the follicles in the hypopigmented spots but not from follicles in normal-looking skin; and (iii

  20. Black holes

    PubMed Central

    Brügmann, B.; Ghez, A. M.; Greiner, J.

    2001-01-01

    Recent progress in black hole research is illustrated by three examples. We discuss the observational challenges that were met to show that a supermassive black hole exists at the center of our galaxy. Stellar-size black holes have been studied in x-ray binaries and microquasars. Finally, numerical simulations have become possible for the merger of black hole binaries. PMID:11553801

  1. [Effect of prostaglandin synthesis inhibitors of diabetic cystoid macular edema].

    PubMed

    Kieselbach, G; Juen, S

    1990-01-01

    In most cases, diabetic macular edema is treated successfully with central laser photocoagulation. However, only few studies report such favorable results in cystoid macular edema, which has a poor visual prognosis. In the present prospective study on diabetics with cystoid macular edema, aged less than 40 years, a better visual outcome was obtained in patients treated with prostaglandin synthesis inhibitors than in an untreated group. PMID:2345629

  2. Inflammation in age-related macular degeneration.

    PubMed

    Ozaki, Ema; Campbell, Matthew; Kiang, Anna-Sophia; Humphries, Marian; Doyle, Sarah L; Humphries, Peter

    2014-01-01

    Age-related macular degeneration (AMD) is the leading cause of legal blindness in elderly individuals in the developed world, affecting 30-50 million people worldwide. AMD primarily affects the macular region of the retina that is responsible for the majority of central, color and daytime vision. The presence of drusen, extracellular protein aggregates that accumulate under the retinal pigment epithelium (RPE), is a major pathological hallmark in the early stages of the disease. The end stage 'dry' and 'wet' forms of the disease culminate in vision loss and are characterized by focal degeneration of the RPE and cone photoreceptors, and choroidal neovascularization (CNV), respectively. Being a multifactorial and genetically heterogeneous disease, the pathophysiology of AMD remains unclear, yet, there is ample evidence supporting immunological and inflammatory processes. Here, we review the recent literature implicating some of these immune processes in human AMD and in animal models. PMID:24664703

  3. Management of pseudophakic cystoid macular edema.

    PubMed

    Guo, Suqin; Patel, Shriji; Baumrind, Ben; Johnson, Keegan; Levinsohn, Daniel; Marcus, Edward; Tannen, Brad; Roy, Monique; Bhagat, Neelakshi; Zarbin, Marco

    2015-01-01

    Pseudophakic cystoid macular edema (PCME) is a common complication following cataract surgery. Acute PCME may resolve spontaneously, but some patients will develop chronic macular edema that affects vision and is difficult to treat. This disease was described more than 50 years ago, and there are multiple options for clinical management. We discuss mechanisms, clinical efficacy, and adverse effects of these treatment modalities. Topical non-steroidal anti-inflammatory agents and corticosteroids are widely used and, when combined, may have a synergistic effect. Intravitreal corticosteroids and anti-vascular endothelial growth factor (anti-VEGF) agents have shown promise when topical medications either fail or have had limited effects. Randomized clinical studies evaluating anti-VEGF agents are needed to fully evaluate benefits and risks. When PCME is either refractory to medical therapy or is associated with significant vitreous involvement, pars plana vitrectomy has been shown to improve outcomes, though it is associated with additional risks.

  4. Increased resolution macular thickness mapping by OCT.

    PubMed

    Bernardes, Rui; Santos, Torcato; Cunha-Vaz, José

    2006-01-01

    Optical coherence tomography (OCT) poor mapping resolution has been pointed out as the biggest disadvantage of this technique when compared to others, e.g., retinal thickness analyzer. In this work we were able to solve this problem by developing an atlas of macular thickness of the human retina into which OCT scans were thereafter registered. This atlas is used to allow registering OCT scans from the Fast Macular Protocol, thus bringing OCT scans into the atlas coordinates, therefore correcting for misfixations, while simultaneously allowing to perform OCT inter-scan registration. From this initial registration, we were able to compute a thickness map into which Fast RNFL Protocol scans were merged, thus allowing for increased OCT mapping resolution. PMID:17946646

  5. Immunology of age-related macular degeneration

    PubMed Central

    Ambati, Jayakrishna; Atkinson, John P.; Gelfand, Bradley D.

    2014-01-01

    Age-related macular degeneration (AMD) is a leading cause of blindness in aged individuals. Recent advances have highlighted the essential role of immune processes in the development, progression and treatment of AMD. In this Review we discuss recent discoveries related to the immunological aspects of AMD pathogenesis. We outline the diverse immune cell types, inflammatory activators and pathways that are involved. Finally, we discuss the future of inflammation-directed therapeutics to treat AMD in the growing aged population. PMID:23702979

  6. [Epidemiology of age related macular degeneration].

    PubMed

    Leveziel, N; Delcourt, C; Zerbib, J; Dollfus, H; Kaplan, J; Benlian, P; Coscas, G; Souied, E H; Soubrane, G

    2009-06-01

    Age-related macular degeneration (ARMD) is a multifactorial and polygenic disease and is the main cause of vision loss in developed countries. The environmental factors of ARMD can modify prevalence and incidence of this disease. This article is a review of the main environmental factors currently recognized as at risk or protective factor for ARMD. Modification of these factors is of crucial importance because it could delay the onset of exudative or atrophic forms of the disease. PMID:19515460

  7. Macular Bioaccelerometers on Earth and in Space

    NASA Technical Reports Server (NTRS)

    Ross, M. D.; Cutler, L.; Meyer, G.; Vazin, P.; Lam, T.

    1991-01-01

    Space flight offers the opportunity to study linear bioaccelerometers (vestibular maculas) in the virtual absence of a primary stimulus, gravitational acceleration. Macular research in space is particularly important to NASA because the bioaccelerometers are proving to be weighted neural networks in which information is distributed for parallel processing. Neural networks are plastic and highly adaptive to new environments. Combined morphological-physiological studies of maculas fixed in space and following flight should reveal macular adaptive responses to microgravity, and their time-course. Ground-based research, already begun, using computer-assisted, 3-dimensional reconstruction of macular terminal fields will lead to development of computer models of functioning maculas. This research should continue in conjunction with physiological studies, including work with multichannel electrodes. The results of such a combined effort could usher in a new era in understanding vestibular function on Earth and in space. They can also provide a rational basis for counter-measures to space motion sickness, which may prove troublesome as space voyager encounter new gravitational fields on planets, or must re-adapt to 1 g upon return to earth.

  8. Role of inflammation in previously untreated macular edema with branch retinal vein occlusion

    PubMed Central

    2014-01-01

    Background The association of inflammatory factors and the aqueous flare value with macular edema in branch retinal vein occlusion (BRVO) patients remains unclear. The relationship between the aqueous flare value and the vitreous fluid levels of vascular endothelial growth factor (VEGF), interleukin (IL)-6, monocyte chemotactic protein (MCP)-1, soluble intercellular adhesion molecule 1 (sICAM-1), and soluble VEGF receptor-2 (sVEGFR-2) was evaluated to investigate the role of inflammation in BRVO associated with macular edema. Aqueous flare values and the vitreous levels of VEGF, IL-6, MCP-1, sICAM-1, and sVEGFR-2 were compared between previously untreated patients with BRVO and patients with macular hole (MH). Methods Vitreous samples were obtained from 45 patients during vitreoretinal surgery (28 patients with BRVO and 17 with MH), and the levels of VEGF, IL-6, MCP-1, sICAM-1, and sVEGFR-2 were measured by enzyme-linked immunosorbent assay. Retinal ischemia was evaluated by measuring the area of capillary non-perfusion using fluorescein angiography and the Scion Image program. Aqueous flare values were measured with a laser flare meter and macular edema was examined by optical coherence tomography. Results The median aqueous flare value was significantly higher in the BRVO group (12.1 photon counts/ms) than in the MH group (4.5 photon counts/ms, P < 0.001). There were significant correlations between the aqueous flare value and the vitreous levels of VEGF, IL-6, MCP-1, and sICAM-1 in the BRVO group (ρ = 0.54, P = 0.005; ρ = 0.56, P = 0.004; ρ = 0.52, P = 0.006; and ρ = 0.47, P = 0.015, respectively). The aqueous flare value was also significantly correlated with the foveal thickness in the BRVO group (ρ = 0.40, P = 0.037). Conclusions Inflammation may induce an increase of vascular permeability and disrupt the blood-aqueous barrier via release of inflammatory factors (VEGF, IL-6, MCP-1, and sICAM-1) in BRVO patients

  9. Safety and efficacy of oral fluorescein angiography in detecting macular edema in comparison with spectral domain optical coherence tomography

    PubMed Central

    Barteselli, Giulio; Chhablani, Jay; Lee, Su Na; Wang, Haiyan; Emam, Sharif El; Kozak, Igor; Cheng, Lingyun; Bartsch, Dirk-Uwe; Azen, Stanley; Freeman, William R.

    2013-01-01

    Purpose To evaluate the safety of oral fluorescein angiography (FA) and to compare its efficacy in detection of macular edema (ME) with spectral-domain optical coherence tomography (SD-OCT). Methods Results of imaging studies for 1,928 eyes of 1,019 patients who had simultaneously undergone both oral FA and SD-OCT by a confocal laser ophthalmoscope (cSLO) were reviewed. Sensitivity in detecting ME, discrepancy rate, and “kappa” agreement were determined for both the techniques, and with eyes stratified by disease diagnosis. Results No allergic reactions occurred after oral FA. Mild gastric discomfort was noted in <1% of the patients. 1,840 eyes (95.4%) showed concordance between the two techniques and “kappa” agreement was 90.3%. For ME, oral FA showed an overall sensitivity of 0.97 and SD-OCT of 0.91. Equivalent sensitivity was found in cases of wet age-related macular degeneration (0.99). Oral FA was more sensitive than SD-OCT in cases of retinovascular diseases. SD-OCT showed higher sensitivity in cases of macular holes. Detection of ME by SD-OCT was significantly higher in cases of intense leakage on oral FA (p<0.001). Conclusions Oral FA proved to be a safe and adequate technique to evaluate ME. It is more sensitive than SD-OCT in detection of ME in cases of retinovascular diseases, but can fail to detect ME in cases of macular holes. A non-invasive examination with simultaneous oral FA and SD-OCT may be considered to obtain a comprehensive evaluation of the presence of ME from different pathologies. PMID:23584697

  10. [Depression in Patients with Age-Related Macular Degeneration].

    PubMed

    Narváez, Yamile Reveiz; Gómez-Restrepo, Carlos

    2012-09-01

    Age-related macular degeneration is a cause for disability in the elderly since it greatly affects their quality of life and increases depression likelihood. This article discusses the negative effect depression has on patients with age-related macular degeneration and summarizes the interventions available for decreasing their depression index. PMID:26572116

  11. [Depression in Patients with Age-Related Macular Degeneration].

    PubMed

    Narváez, Yamile Reveiz; Gómez-Restrepo, Carlos

    2012-09-01

    Age-related macular degeneration is a cause for disability in the elderly since it greatly affects their quality of life and increases depression likelihood. This article discusses the negative effect depression has on patients with age-related macular degeneration and summarizes the interventions available for decreasing their depression index.

  12. Acetazolamide for cystoid macular oedema in Bietti crystalline retinal dystrophy.

    PubMed

    Broadhead, Geoffrey K; Chang, Andrew A

    2014-04-01

    Bietti crystalline retinal dystrophy is a rare, inherited disorder whose hallmark is the presence of retinal crystal deposits associated with later chorioretinal degeneration. This condition may rarely be complicated by the development of cystoid macular oedema leading to rapid visual decline. Currently, treatment options for this complication of Bietti dystrophy are limited and the visual prognosis is poor. Here, we present a case of cystoid macular oedema associated with Bietti dystrophy that was successfully diagnosed using multimodal imaging techniques including optical coherence tomography and fluorescein angiography. These modalities confirmed the diagnosis of macular oedema and excluded other possible causes of oedema such as choroidal neovascularisation. In this patient, cystoid macular oedema was resolved with oral acetazolamide therapy, a treatment that has not been previously reported in this context. Acetazolamide treatment resulted in oedema resolution and improvement in visual function, and can be considered a therapeutic option for other patients with Bietti dystrophy who develop cystoid macular oedema.

  13. Macular edema in branch retinal vein occlusion: types and treatment.

    PubMed

    Jalkh, A E; Trempe, C L

    1989-01-01

    In this study of branch retinal vein occlusion, we distinguished between cystoid macular edema caused by increased capillary pressure and noncystoid edema due to hard exudates in the macula caused by chronic leakage from vascular abnormalities in the posterior pole or midperiphery. We performed laser photocoagulation in 51 eyes with cystoid macular edema to achieve focal narrowing of the retinal arterioles perfusing the macular area affected by the cystoid edema; good anatomic and functional results were achieved in 40 of these eyes (78%). In 25 of the five eyes, the treated segment of the retinal arteriole was outside the area of macular edema; results were successful in 19 of these eyes (76%). In 14 eyes with noncystoid exudative macular edema, we performed laser photocoagulation to the vascular abnormalities; good anatomic and functional results were obtained in 12 of these (86%). PMID:2927879

  14. Measurement of macular pigment optical density in a healthy chinese population sample

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Macular pigment may protect against age-related macular degeneration (AMD) by its capability to absorb blue light and scavenge free radicals. Current information on human macular pigment density has been largely from studies on Caucasians populations. The purpose of this study was to assess macular ...

  15. Iris angiography in cystoid macular edema after cataract extraction.

    PubMed

    Kottow, M; Hendrickson, P

    1975-07-01

    Iris angiography was performed on eight patients (nine eyes), who had cystoid macular edema postcataract extraction. The fundus fluorescein angiographies showed typical star-shaped, multiloculated staining of the macular area. The iris angiographies demonstrated moderate to massive leakage of dye from the iris, and possibly leakage of ciliary body vessels into the anterior chamber, thus evidencing the until now suspected but undocumented fact that fluorescein leakage is not restricted to the fundus vessels. These data tend to support the idea that this type of macular edema is due to a vascular abnormality, and not to altered vitreous mechanics.

  16. Vision loss without Amsler grid abnormalities in macular subretinal neovascularization.

    PubMed

    Roy, M S

    1985-01-01

    An 87-year-old woman, with known atrophic senile macular degeneration in one eye, had isolated decreased reading ability while Amsler grid testing was normal. This led to the early diagnosis of macular subretinal neovascularization in the other eye. Thus patients at high risk for neovascular macular degeneration should be made aware of possible subtle changes in vision as well as abnormalities in the Amsler grid. Regular visual acuity check and careful biomicroscopic examination of the macula should be part of each follow-up examination.

  17. Retinal holes.

    PubMed

    Foos, R Y

    1978-09-01

    Holes of the peripheral retina, defined as full-thickness breaks of trophic origin with no associated flap or free operculum, were found in 136 (2.4%) eyes from 2,800 autopsied subjects. Primary retinal holes (those with no indication of a proximal causative lesion and with no lattice degeneration in either eye) occurred in only eight of the 5,600 eyes studied; all were unilateral, single, less than 0.25 disk diameter in size, within the basal zone, and in eyes from elderly subjects. Secondary holes were found in 128 (2.3%) of eyes and of these, lattice degeneration was the most common cause (103). Other lesions complicated by hole formation included zonular traction tufts (10), chorioretinitis (9), meridional folds (3), and pavingstone degeneration (2). Retinal holes in surgically aphakic eyes did not differ qualitatively or quantitatively from those in age-matched phakic eyes.

  18. Macular dazzling test on normal subjects.

    PubMed Central

    Gomez-Ulla, F; Louro, O; Mosquera, M

    1986-01-01

    The macular dazzling test was performed on 240 healthy eyes, classified into six groups according to the ages of the subjects. The test was used to assess both long distance and short distance vision with a simultaneous study of the influence of mydriasis and miosis. The MDT is a test easy to perform, requires a minimum of co-operation by the subject, and gives repeatable results. The MDT values increase significantly as the age of the subject increases. The sex of the subject has no influence on it, and there are no significant differences between a subject's right and left eyes. Mydriasis does not affect the MDT, but miosis reduces the recovery period. All the values are statistically greater for long distance vision than for short distance vision. PMID:3954979

  19. Update on corticosteroids for diabetic macular edema.

    PubMed

    Schwartz, Stephen G; Scott, Ingrid U; Stewart, Michael W; Flynn, Harry W

    2016-01-01

    Diabetic macular edema (DME) remains an important cause of visual loss. Although anti-vascular endothelial growth factor (VEGF) agents are generally used as first-line treatments for patients with center-involving DME, there is an important role for corticosteroids as well. Corticosteroids may be especially useful in pseudophakic patients poorly responsive to anti-VEGF therapies, in patients wishing to reduce the number of required injections, and in pregnant patients. Intravitreal triamcinolone acetonide has been used for many years but is not approved for this indication. An extended-release bioerodable dexamethasone delivery system and an extended-release nonbioerodable fluocinolone acetonide insert have both achieved regulatory approval for the treatment of DME. All intravitreal corticosteroids are associated with risks of cataract progression, elevation of intraocular pressure, and endophthalmitis. There is no current consensus regarding the use of corticosteroids, but they are valuable for selected patients with center-involving DME. PMID:27660409

  20. Update on corticosteroids for diabetic macular edema

    PubMed Central

    Schwartz, Stephen G; Scott, Ingrid U; Stewart, Michael W; Flynn, Harry W

    2016-01-01

    Diabetic macular edema (DME) remains an important cause of visual loss. Although anti-vascular endothelial growth factor (VEGF) agents are generally used as first-line treatments for patients with center-involving DME, there is an important role for corticosteroids as well. Corticosteroids may be especially useful in pseudophakic patients poorly responsive to anti-VEGF therapies, in patients wishing to reduce the number of required injections, and in pregnant patients. Intravitreal triamcinolone acetonide has been used for many years but is not approved for this indication. An extended-release bioerodable dexamethasone delivery system and an extended-release nonbioerodable fluocinolone acetonide insert have both achieved regulatory approval for the treatment of DME. All intravitreal corticosteroids are associated with risks of cataract progression, elevation of intraocular pressure, and endophthalmitis. There is no current consensus regarding the use of corticosteroids, but they are valuable for selected patients with center-involving DME. PMID:27660409

  1. Update on corticosteroids for diabetic macular edema

    PubMed Central

    Schwartz, Stephen G; Scott, Ingrid U; Stewart, Michael W; Flynn, Harry W

    2016-01-01

    Diabetic macular edema (DME) remains an important cause of visual loss. Although anti-vascular endothelial growth factor (VEGF) agents are generally used as first-line treatments for patients with center-involving DME, there is an important role for corticosteroids as well. Corticosteroids may be especially useful in pseudophakic patients poorly responsive to anti-VEGF therapies, in patients wishing to reduce the number of required injections, and in pregnant patients. Intravitreal triamcinolone acetonide has been used for many years but is not approved for this indication. An extended-release bioerodable dexamethasone delivery system and an extended-release nonbioerodable fluocinolone acetonide insert have both achieved regulatory approval for the treatment of DME. All intravitreal corticosteroids are associated with risks of cataract progression, elevation of intraocular pressure, and endophthalmitis. There is no current consensus regarding the use of corticosteroids, but they are valuable for selected patients with center-involving DME.

  2. [Epidemiology of age-related macular degeneration].

    PubMed

    Brandl, C; Stark, K J; Wintergerst, M; Heinemann, M; Heid, I M; Finger, R P

    2016-09-01

    Age-related macular degeneration (AMD) is the main cause of blindness in industrialized societies. Population-based epidemiological investigations generate important data on prevalence, incidence, risk factors, and future trends. This review summarizes the most important epidemiological studies on AMD with a focus on their transferability to Germany including existing evidence for the main risk factors for AMD development and progression. Future tasks, such as the standardization of grading systems and the use of recent retinal imaging technology in epidemiological studies are discussed. In Germany, epidemiological data on AMD are scarce. However, the need for epidemiological research in ophthalmology is currently being addressed by several recently started population-based studies. PMID:27541733

  3. Pseudophakic cystoid macular edema: update 2016

    PubMed Central

    Grzybowski, Andrzej; Sikorski, Bartosz L; Ascaso, Francisco J; Huerva, Valentín

    2016-01-01

    Pseudophakic cystoid macular edema (PCME) is the most common complication of cataract surgery, leading in some cases to a decrease in vision. Although the pathogenesis of PCME is not completely understood, the contribution of postsurgical inflammation is generally accepted. Consequently, anti-inflammatory medicines, including steroids and nonsteroidal anti-inflammatory drugs, have been postulated as having a role in both the prophylaxis and treatment of PCME. However, the lack of a uniformly accepted PCME definition, conflicting data on some risk factors, and the scarcity of studies comparing the role of nonsteroidal anti-inflammatory drugs to steroids in PCME prevention make the problem of PCME one of the puzzles of ophthalmology. This paper presents an updated review on the pathogenesis, risk factors, and use of anti-inflammatory drugs in PCME that reflect current research and practice.

  4. Pseudophakic cystoid macular edema: update 2016

    PubMed Central

    Grzybowski, Andrzej; Sikorski, Bartosz L; Ascaso, Francisco J; Huerva, Valentín

    2016-01-01

    Pseudophakic cystoid macular edema (PCME) is the most common complication of cataract surgery, leading in some cases to a decrease in vision. Although the pathogenesis of PCME is not completely understood, the contribution of postsurgical inflammation is generally accepted. Consequently, anti-inflammatory medicines, including steroids and nonsteroidal anti-inflammatory drugs, have been postulated as having a role in both the prophylaxis and treatment of PCME. However, the lack of a uniformly accepted PCME definition, conflicting data on some risk factors, and the scarcity of studies comparing the role of nonsteroidal anti-inflammatory drugs to steroids in PCME prevention make the problem of PCME one of the puzzles of ophthalmology. This paper presents an updated review on the pathogenesis, risk factors, and use of anti-inflammatory drugs in PCME that reflect current research and practice. PMID:27672316

  5. Age-related macular degeneration: current treatments

    PubMed Central

    Hubschman, Jean Pierre; Reddy, Shantan; Schwartz, Steven D

    2009-01-01

    Purpose: Although important progress has been made in understanding age-related macular degeneration (AMD), management of the disease continues to be a challenge. AMD research has led to a widening of available treatment options and improved prognostic perspectives. This essay reviews these treatment options. Design: Interpretative essay. Methods: Literature review and interpretation. Results: Current treatments to preserve vision in patients with non-exudative AMD include antioxidant vitamins and mineral supplementations. Exudative AMD is currently most often treated monthly with anti-VEGF intravitreal injections. However, investigators are beginning to experiment with combination therapy and surgical approaches in an attempt to limit the number of treatment and reduce the financial burden on the health care system. Conclusion: By better understanding the basis and pathogenesis of AMD, newer therapies will continue to be developed that target specific pathways in patients with AMD, with the hoped for outcome of better management of the disease and improved visual acuity. PMID:19668560

  6. Ziv-aflibercept in macular disease

    PubMed Central

    Mansour, Ahmad M; Al-Ghadban, Sara I; Yunis, Muhammad H; El-Sabban, Marwan E

    2015-01-01

    Background/aims Aflibercept is an approved therapy for neovascular age-related macular degeneration (AMD) and diabetic macular oedema (DME). In vitro and in vivo studies did not detect toxicity to the retinal pigment epithelium cells using the approved cancer protein, ziv-aflibercept. Our purpose is to determine if ziv-aflibercept can be used in AMD and DME without ocular toxicity, to test the stability of ziv-aflibercept, and to do a cost analysis. Methods Prospectively, consecutive patients with AMD or DME and poor vision underwent one intravitreal injection of 0.05 mL of fresh filtered ziv-aflibercept (1.25 mg). Monitoring of best-corrected visual acuity, intraocular inflammation, cataract progression, and retinal structure by spectral domain optical coherence tomography was done at 1 day and 1 week after injection. Ziv-aflibercept activity over 4 weeks was measured by capturing vascular endothelial growth factor by ELISA. Results There were no signs of retinal toxicity, intraocular inflammation or change in lens status in four eyes with AMD and two eyes with DME. Visual acuity improved (p=0.05) and central foveal thickness decreased in all patients (p=0.05). Ziv-aflibercept had no loss of anti-VEGF activity when kept at 4°C in polycarbonate syringes over 4 weeks. Similar to bevacizumab, compounded ziv-aflibercept would yield a tremendous saving compared with aflibercept or ranibizumab. Conclusions Off-label use of ziv-aflibercept improves visual acuity without ocular toxicity and may offer a cheaper alternative to the same molecule aflibercept. Trial registration number NCT02173873. PMID:25677668

  7. Macular xanthophylls, lipoprotein-related genes, and age-related macular degeneration1234

    PubMed Central

    Koo, Euna; Neuringer, Martha; SanGiovanni, John Paul

    2014-01-01

    Plant-based macular xanthophylls (MXs; lutein and zeaxanthin) and the lutein metabolite meso-zeaxanthin are the major constituents of macular pigment, a compound concentrated in retinal areas that are responsible for fine-feature visual sensation. There is an unmet need to examine the genetics of factors influencing regulatory mechanisms and metabolic fates of these 3 MXs because they are linked to processes implicated in the pathogenesis of age-related macular degeneration (AMD). In this work we provide an overview of evidence supporting a molecular basis for AMD-MX associations as they may relate to DNA sequence variation in AMD- and lipoprotein-related genes. We recognize a number of emerging research opportunities, barriers, knowledge gaps, and tools offering promise for meaningful investigation and inference in the field. Overviews on AMD- and high-density lipoprotein (HDL)–related genes encoding receptors, transporters, and enzymes affecting or affected by MXs are followed with information on localization of products from these genes to retinal cell types manifesting AMD-related pathophysiology. Evidence on the relation of each gene or gene product with retinal MX response to nutrient intake is discussed. This information is followed by a review of results from mechanistic studies testing gene-disease relations. We then present findings on relations of AMD with DNA sequence variants in MX-associated genes. Our conclusion is that AMD-associated DNA variants that influence the actions and metabolic fates of HDL system constituents should be examined further for concomitant influence on MX absorption, retinal tissue responses to MX intake, and the capacity to modify MX-associated factors and processes implicated in AMD pathogenesis. PMID:24829491

  8. Reduced macular function in ABCA4 carriers

    PubMed Central

    2015-01-01

    carriers demonstrated reduced macular function measured by mERG along with none to subtle and even extensive morphological retinal changes. The c.768 G>T, c.5461–10T>C, and c.319 C>T mutations were associated with the most deviant ERGs, including both significant reduction of mERG amplitudes and prolongation of mERG ITs, as well as with reduced amplitude or delayed IT for the 30 Hz flicker ffERG in a few cases. They may therefore be considered serious mutations. The c.5917delG and c.4469 G>A mutations were associated with milder or no macular alteration. Long-term follow-up of these and other ABCA4 carriers may be of importance to elucidate the role of ABCA4 mutations in age-related macular degeneration. Moreover, improved knowledge of separate ABCA4 mutations may help us to better understand their role in ABCA4-associated retinal degenerations. PMID:26261413

  9. [Transmissing electron microscopy of the vitreo-macular border in clinically significant diabetic macular edema].

    PubMed

    Synek, S; Pác, L; Synková, M

    2007-09-01

    The authors examined samples of the epimacular tissue in clinically significant macular edema by means of the transmissing electron microscopy. They did not found morphological differences between samples from patients already treated by means of laser photocoagulation before the pars plana vitrectomy and those without the laser treatment. Findings may be divided into three groups: (1) the inner limiting membrane (ILM) covered with collagen vitreous fibers, (2) cells' elements of the fibroblasts category, and (3) fibrous astrocytes in the vitreous cortex constituting one- or multilayer cellular membranes.

  10. Parainflammation, chronic inflammation, and age-related macular degeneration.

    PubMed

    Chen, Mei; Xu, Heping

    2015-11-01

    Inflammation is an adaptive response of the immune system to noxious insults to maintain homeostasis and restore functionality. The retina is considered an immune-privileged tissue as a result of its unique anatomic and physiologic properties. During aging, the retina suffers from a low-grade chronic oxidative insult, which sustains for decades and increases in level with advancing age. As a result, the retinal innate-immune system, particularly microglia and the complement system, undergoes low levels of activation (parainflammation). In many cases, this parainflammatory response can maintain homeostasis in the healthy aging eye. However, in patients with age-related macular degeneration, this parainflammatory response becomes dysregulated and contributes to macular damage. Factors contributing to the dysregulation of age-related retinal parainflammation include genetic predisposition, environmental risk factors, and old age. Dysregulated parainflammation (chronic inflammation) in age-related macular degeneration damages the blood retina barrier, resulting in the breach of retinal-immune privilege, leading to the development of retinal lesions. This review discusses the basic principles of retinal innate-immune responses to endogenous chronic insults in normal aging and in age-related macular degeneration and explores the difference between beneficial parainflammation and the detrimental chronic inflammation in the context of age-related macular degeneration.

  11. X-linked recessive atrophic macular degeneration from RPGR mutation.

    PubMed

    Ayyagari, Radha; Demirci, F Yesim; Liu, Jiafan; Bingham, Eve L; Stringham, Heather; Kakuk, Laura E; Boehnke, Michael; Gorin, Michael B; Richards, Julia E; Sieving, Paul A

    2002-08-01

    We mapped a new X-linked recessive atrophic macular degeneration locus to Xp21.1-p11.4 and show allelic involvement of the gene RPGR, which normally causes severe peripheral retinal degeneration leading to global blindness. Ten affected males whom we examined had primarily macular atrophy causing progressive loss of visual acuity with minimal peripheral visual impairment. One additional male showed extensive macular degeneration plus peripheral loss of retinal pigment epithelium and choriocapillaries. Full-field electroretinograms (ERGs) showed normal cone and rod responses in some affected males despite advanced macular degeneration, emphasizing the dissociation of atrophic macular degeneration from generalized cone degenerations, including X-linked cone dystrophy (COD1). The RPGR gene nonsense mutation G-->T at open reading frame (ORF)15+1164 cosegregated with the disease and may create a donor splice site. Identification of an RPGR mutation in atrophic maculardegeneration expands the phenotypic range associated with this gene and provides a new tool for the dissection of the relationship between clinically different retinal pathologies.

  12. Observational study of subclinical diabetic macular edema

    PubMed Central

    Bressler, N M; Miller, K M; Beck, R W; Bressler, S B; Glassman, A R; Kitchens, J W; Melia, M; Schlossman, D K

    2012-01-01

    Purpose To determine the rate of progression of eyes with subclinical diabetic macular edema (DME) to clinically apparent DME or DME necessitating treatment during a 2-year period. Methods In all, 43 eyes from 39 study participants with subclinical DME, defined as absence of foveal center edema as determined with slit lamp biomicroscopy but a center point thickness (CPT) between 225 and 299 μm on time domain (Stratus, Carl Zeiss Meditec) optical coherence tomography (OCT) scan, were enrolled from 891 eyes of 582 subjects screened. Eyes were evaluated annually for up to 2 years for the primary outcome, which was an increase in OCT CPT of at least 50 μm from baseline and a CPT of at least 300 μm, or treatment for DME (performed at the discretion of the investigator). Results The cumulative probability of meeting an increase in OCT CPT of at least 50 μm from baseline and a CPT of at least 300 μm, or treatment for DME was 27% (95% confidence interval (CI): 14%, 38%) by 1 year and 38% (95% CI: 23%, 50%) by 2 years. Conclusions Although subclinical DME may be uncommon, this study suggests that between approximately one-quarter and one-half of eyes with subclinical DME will progress to more definite thickening or be judged to need treatment for DME within 2 years after its identification. PMID:22441027

  13. Animal models of age related macular degeneration

    PubMed Central

    Pennesi, Mark E.; Neuringer, Martha; Courtney, Robert J.

    2013-01-01

    Age related macular degeneration (AMD) is the leading cause of vision loss of those over the age of 65 in the industrialized world. The prevalence and need to develop effective treatments for AMD has lead to the development of multiple animal models. AMD is a complex and heterogeneous disease that involves the interaction of both genetic and environmental factors with the unique anatomy of the human macula. Models in mice, rats, rabbits, pigs and non-human primates have recreated many of the histological features of AMD and provided much insight into the underlying pathological mechanisms of this disease. In spite of the large number of models developed, no one model yet recapitulates all of the features of human AMD. However, these models have helped reveal the roles of chronic oxidative damage, inflammation and immune dysregulation, and lipid metabolism in the development of AMD. Models for induced choroidal neovascularization have served as the backbone for testing new therapies. This article will review the diversity of animal models that exist for AMD as well as their strengths and limitations. PMID:22705444

  14. Diabetic Macular Edema Pathophysiology: Vasogenic versus Inflammatory

    PubMed Central

    Baget-Bernaldiz, Marc; Pareja-Rios, Alicia; Lopez-Galvez, Maribel; Navarro-Gil, Raul; Verges, Raquel

    2016-01-01

    Diabetic macular edema (DME) can cause blindness in diabetic patients suffering from diabetic retinopathy (DR). DM parameters controls (glycemia, arterial tension, and lipids) are the gold standard for preventing DR and DME. Although the vascular endothelial growth factor (VEGF) is known to play a role in the development of DME, the pathological processes leading to the onset of this disease are highly complex and the exact sequence in which they occur is still not completely understood. Angiogenesis and inflammation have been shown to be involved in the pathogenesis of this disease. However, it still remains to be clarified whether angiogenesis following VEGF overexpression is a cause or a consequence of inflammation. This paper provides a review of the data currently available, focusing on VEGF, angiogenesis, and inflammation. Our analysis suggests that angiogenesis and inflammation act interdependently during the development of DME. Knowledge of DME etiology seems to be important in treatments with anti-VEGF or anti-inflammatory drugs. Current diagnostic techniques do not permit us to differentiate between both etiologies. In the future, diagnosing the physiopathology of each patient with DME will help us to select the most effective drug. PMID:27761468

  15. Macular pigment assessment by motion photometry.

    PubMed

    Moreland, J D

    2004-10-15

    A Moreland anomaloscope was modified to measure macular pigment optical density (MPOD) profiles by motion photometry. A grating (spatial frequency 0.38 c deg(-1)), whose alternate bars were filled, respectively, with 460 nm (maximum MP absorption) and 580 nm (zero MP absorption) lights, drifted steadily at 37 degrees s(-1). The subject adjusted the 580 nm radiance to minimise perceived motion (equiluminance between 460 and 580 nm). Five or more settings were made for two foveal fields (0.9 degrees and 2.2 degrees diameter) and 11 extrafoveal annular fields (0.8 degrees -7.5 degrees eccentricity). Twenty subjects made measurements for both eyes: some with replications. MPOD profiles varied in scale (0.18-0.75 for the 0.9 degrees foveal field) and in shape. A mean profile was derived. Foveal data were optimally aligned with annular data in that profile when plotted at 0.71 of the foveal field radius. Factors that limit precision were identified, such as fixation errors foveally and Troxler's effect parafoveally.

  16. New Computer Simulations of Macular Neural Functioning

    NASA Technical Reports Server (NTRS)

    Ross, Muriel D.; Doshay, D.; Linton, S.; Parnas, B.; Montgomery, K.; Chimento, T.

    1994-01-01

    We use high performance graphics workstations and supercomputers to study the functional significance of the three-dimensional (3-D) organization of gravity sensors. These sensors have a prototypic architecture foreshadowing more complex systems. Scaled-down simulations run on a Silicon Graphics workstation and scaled-up, 3-D versions run on a Cray Y-MP supercomputer. A semi-automated method of reconstruction of neural tissue from serial sections studied in a transmission electron microscope has been developed to eliminate tedious conventional photography. The reconstructions use a mesh as a step in generating a neural surface for visualization. Two meshes are required to model calyx surfaces. The meshes are connected and the resulting prisms represent the cytoplasm and the bounding membranes. A finite volume analysis method is employed to simulate voltage changes along the calyx in response to synapse activation on the calyx or on calyceal processes. The finite volume method insures that charge is conserved at the calyx-process junction. These and other models indicate that efferent processes act as voltage followers, and that the morphology of some afferent processes affects their functioning. In a final application, morphological information is symbolically represented in three dimensions in a computer. The possible functioning of the connectivities is tested using mathematical interpretations of physiological parameters taken from the literature. Symbolic, 3-D simulations are in progress to probe the functional significance of the connectivities. This research is expected to advance computer-based studies of macular functioning and of synaptic plasticity.

  17. Physics of Age Related Macular Degeneration

    NASA Astrophysics Data System (ADS)

    Family, Fereydoon

    2009-11-01

    Age-related macular degeneration (AMD) is the leading cause of blindness beyond the age of 50 years. The most common pathogenic mechanism that leads to AMD is choroidal neovascularization (CNV). CNV is produced by accumulation of residual material caused by aging of retinal pigment epithelium cells (RPE). The RPE is a phagocytic system that is essential for renewal of photoreceptors (rods and cones). With time, incompletely degraded membrane material builds up in the form of lipofuscin. Lipofuscin is made of free-radical-damaged protein and fat, which forms not only in AMD, but also Alzheimer's disease, and Parkinson's disease. The study of lipofuscin formation and growth is important, because of their association with cellular aging. In this talk I will discuss a model of non-equilibrium cluster growth that we have developed for studying the formation and growth of lipofuscin in AMD [K.I. Mazzitello, C.M. Arizmendi, Fereydoon Family, H. E. Grossniklaus, Physical Review E (2009)]. I will also present an overview of our theoretical and computational efforts in modeling some other aspects of the physics of AMD, including CNV and the breakdown of Bruch's membrane [Ongoing collaboration with Abbas Shirinifard and James A. Glazier, Biocomplexity Institute and Department of Physics, Indiana University, Y. Jiang, Los Alamos, and Hans E. Grossniklaus, Department of Ophthalmology, Emory University].

  18. Mechanisms of age-related macular degeneration

    PubMed Central

    Ambati, Jayakrishna; Fowler, Benjamin J.

    2012-01-01

    Age-related macular degeneration (AMD), a progressive condition that is untreatable in up to 90% of patients, is a leading cause of blindness in the elderly worldwide. The two forms of AMD, wet and dry, are classified based on the presence or absence of blood vessels that have disruptively invaded the retina, respectively. A detailed understanding of the molecular mechanisms underlying wet AMD has led to several robust FDA-approved therapies. In contrast, there are not any approved treatments for dry AMD. In this review, we provide insight into the critical effector pathways that mediate each form of disease. The interplay of immune and vascular systems for wet AMD, and the proliferating interest in hunting for gene variants to explain AMD pathogenesis, are placed in the context of the latest clinical and experimental data. Emerging models of dry AMD pathogenesis are presented, with a focus on DICER1 deficit and the toxic accumulation of retinal debris. A recurring theme that spans most aspects of AMD pathogenesis is defective immune modulation in the classically immune-privileged ocular haven. Interestingly, the latest advances in AMD research highlight common molecular disease pathways with other common neurodegenerations. Finally, the therapeutic potential of intervening at known mechanisms of AMD pathogenesis is discussed. PMID:22794258

  19. Statistical physics of age related macular degeneration

    NASA Astrophysics Data System (ADS)

    Family, Fereydoon; Mazzitello, K. I.; Arizmendi, C. M.; Grossniklaus, H. E.

    Age-related macular degeneration (AMD) is the leading cause of blindness beyond the age of 50 years. The most common pathogenic mechanism that leads to AMD is choroidal neovascularization (CNV). CNV is produced by accumulation of residual material caused by aging of retinal pigment epithelium cells (RPE). The RPE is a phagocytic system that is essential for renewal of photoreceptors (rods and cones). With time, incompletely degraded membrane material builds up in the form of lipofuscin. Lipofuscin is made of free-radical-damaged protein and fat, which forms not only in AMD, but also Alzheimer disease and Parkinson disease. The study of lipofuscin formation and growth is important, because of their association with cellular aging. We introduce a model of non-equilibrium cluster growth and aggregation that we have developed for studying the formation and growth of lipofuscin in the aging RPE. Our results agree with a linear growth of the number of lipofuscin granules with age. We apply the dynamic scaling approach to our model and find excellent data collapse for the cluster size distribution. An unusual feature of our model is that while small particles are removed from the RPE the larger ones become fixed and grow by aggregation.

  20. Macular pseudohaemorrhage secondary to Allen Dot artefact.

    PubMed

    Michaels, Luke; Alexander, Philip; Newsom, Richard

    2015-01-01

    A 34-year-old highly myopic (-11.00 D) woman presented to eye clinic with a 3 day history of right eye paracentral blurring. Visual acuities were 6/6 bilaterally. Clinical examination was normal. Fundus photography showed the classic appearance of a macular haemorrhage. This is a recognised complication of high myopia and would have accounted for the patient's symptoms. However, further photography showed that the haemorrhage seemed to 'jump' around the fundus and was even present in the fellow eye. The apparent haemorrhage was revealed to be an imaging artefact. The 'Allen Dot' is a 6 mm black mask incorporated into retinal cameras to reduce reflection. Rarely, in highly myopic eyes, optical artefact can result. To the best of our knowledge, we are the first in the literature to report artefacts from the Allen Dot masquerading as ophthalmic disease. This case re-iterates the importance of clinical examination, especially in high myopes, given the current trend towards virtual clinics. PMID:25564595

  1. Diabetic macular edema, retinopathy and age-related macular degeneration as inflammatory conditions

    PubMed Central

    2016-01-01

    Diabetic macular edema (DME) and diabetic retinopathy (DR) are complications affecting about 25% of all patients with long-standing type 1 and type 2 diabetes mellitus and are a major cause of significant decrease in vision and quality of life. Age-related macular degeneration (AMD) is not uncommon, and diabetes mellitus affects the incidence and progression of AMD through altering hemodynamics, increasing oxidative stress, accumulating advanced glycation end products, etc. Recent studies suggest that DME, DR and AMD are inflammatory conditions characterized by a breakdown of the blood-retinal barrier, inflammatory processes and an increase in vascular permeability. Key factors that seem to have a dominant role in DME, DR and AMD are angiotensin II, prostaglandins and the vascular endothelial growth factor and a deficiency of anti-inflammatory bioactive lipids. The imbalance between pro- and anti-inflammatory eicosanoids and enhanced production of pro-angiogenic factors may initiate the onset and progression of DME, DR and AMD. This implies that bioactive lipids that possess anti-inflammatory actions and suppress the production of angiogenic factors could be employed in the prevention and management of DME, DR and AMD.

  2. Diabetic macular edema, retinopathy and age-related macular degeneration as inflammatory conditions

    PubMed Central

    2016-01-01

    Diabetic macular edema (DME) and diabetic retinopathy (DR) are complications affecting about 25% of all patients with long-standing type 1 and type 2 diabetes mellitus and are a major cause of significant decrease in vision and quality of life. Age-related macular degeneration (AMD) is not uncommon, and diabetes mellitus affects the incidence and progression of AMD through altering hemodynamics, increasing oxidative stress, accumulating advanced glycation end products, etc. Recent studies suggest that DME, DR and AMD are inflammatory conditions characterized by a breakdown of the blood-retinal barrier, inflammatory processes and an increase in vascular permeability. Key factors that seem to have a dominant role in DME, DR and AMD are angiotensin II, prostaglandins and the vascular endothelial growth factor and a deficiency of anti-inflammatory bioactive lipids. The imbalance between pro- and anti-inflammatory eicosanoids and enhanced production of pro-angiogenic factors may initiate the onset and progression of DME, DR and AMD. This implies that bioactive lipids that possess anti-inflammatory actions and suppress the production of angiogenic factors could be employed in the prevention and management of DME, DR and AMD. PMID:27695506

  3. [Literature review: Diabetic macular edema. Repercussions and treatment].

    PubMed

    Carmona-Moxica, Luis Roberto; Hernández-Núñez, Fabiola

    2015-01-01

    In our country there is a report of prevalence of Diabetes Mellitus in the adult population of a 10%, occupying one of the first causes of morbidity-mortality, also visual and labor incapacity. Macular edema is the first cause of lost vision in the diabetic patient. There are classic methods to detect it, as the examination with biomicroscope, indirect ophthalmoscopy, fluorangiography (FAR), and the new and gold standard method for diagnostic and sequence examination, Ocular Coherence Tomography (OCT). With OCT had been possible the study of distinct types of macular edema, that could represent distinct clinical states, with specific treatments. The protocol of treatment of macular edema, continues changing. The traditional methods as metabolic control and fotocoagulation with Laser now have more options as intravitreal injection of triamcinolone, or antiangiogenic substances, even surgical treatment with vitrectomy. There are many prospective and randomized studies evaluating this methods, so until now is difficult to determine which treatment is the best.

  4. Effects of Vitreomacular Adhesion on Age-Related Macular Degeneration

    PubMed Central

    Kang, Eui Chun; Koh, Hyoung Jun

    2015-01-01

    Herein, we review the association between vitreomacular adhesion (VMA) and neovascular age-related macular degeneration (AMD). Meta-analyses have shown that eyes with neovascular AMD are twice as likely to have VMA as normal eyes. VMA in neovascular AMD may induce inflammation, macular traction, decrease in oxygenation, sequestering of vascular endothelial growth factor (VEGF), and other cytokines or may directly stimulate VEGF production. VMA may also interfere with the treatment effects of anti-VEGF therapy, which is the standard treatment for neovascular AMD, and releasing VMA can improve the treatment response to anti-VEGF treatment in neovascular AMD. We also reviewed currently available methods of relieving VMA. PMID:26425354

  5. Topical Nonsteroidal Anti-Inflammatory Drugs for Macular Edema

    PubMed Central

    Parmeggiani, Francesco; Romano, Mario R.; dell'Omo, Roberto

    2013-01-01

    Nonsteroidal anti-inflammatory drugs (NSAIDs) are nowadays widely used in ophthalmology to reduce eye inflammation, pain, and cystoid macular edema associated with cataract surgery. Recently, new topical NSAIDs have been approved for topical ophthalmic use, allowing for greater drug penetration into the vitreous. Hence, new therapeutic effects can be achieved, such as reduction of exudation secondary to age-related macular degeneration or diabetic maculopathy. We provide an updated review on the clinical use of NSAIDs for retinal diseases, with a focus on the potential future applications. PMID:24227908

  6. UNUSUAL PRESENTATION OF GENERALIZED MACULAR AMYLOIDOSIS IN A YOUNG ADULT

    PubMed Central

    Kudur, Mohan H; B, Sathish Pai; H, Sripathi; Prabhu, Smitha

    2008-01-01

    Macular amyloidosis is a common problem seen dermatology out-patient department. Generalized macular amyloidosis presenting with a poikilodermatous appearance is rare. In our case, an 18-year-old male presented with generalized hypopigmented macules with a poikilodermatous appearance of 10-year duration. His developmental milestones were normal with negative family history of similar complaints. Histopathology of hyperpigmented lesions revealed hyperkeratosis and acanthosis of epidermis and hypopigmented lesion showing only hyperkeratosis. Both lesions were showing the deposition of amorphous, hazy material in the tips of papillary dermis with perivascular inflammatory infiltrate. Congo red staining of the amorphous material was positive for amyloid. PMID:19882037

  7. Comparison of Modified-ETDRS and Mild Macular Grid Laser Photocoagulation Strategies for Diabetic Macular Edema

    PubMed Central

    2008-01-01

    Purpose To compare two laser photocoagulation techniques for treatment of diabetic macular edema (DME): modified-ETDRS direct/grid photocoagulation (mETDRS) and a, potentially milder, but potentially more extensive, mild macular grid (MMG) laser technique in which small mild burns are placed throughout the macula, whether or not edema is present, and microaneurysms are not treated directly. Methods 263 subjects (mean age 59 years) with previously untreated DME were randomly assigned to receive laser photocoagulation by mETDRS (N=162 eyes) or MMG (N=161 eyes) technique. Visual acuity, fundus photographs and OCT measurements were obtained at baseline and after 3.5, 8, and 12 months. Treatment was repeated if DME persisted. Main Outcome Measure Change in OCT measures at 12-months follow up. Results From baseline to 12 months, among eyes with baseline central subfield thickness ≥ 250 microns, central subfield thickening decreased by an average of 88 microns in the mETDRS group and decreased by 49 microns in the MMG group (adjusted mean difference: 33 microns, 95% confidence interval 5 to 61 microns, P=0.02). Weighted inner zone thickening by OCT decreased by 42 and 28 microns, respectively (adjusted mean difference: 14 microns, 95% confidence interval 1 to 27 microns, P=0.04), maximum retinal thickening (maximum of the central and four inner subfields) decreased by 66 and 39 microns, respectively (adjusted mean difference: 27 microns, 95% confidence interval 6 to 47 microns, P=0.01), and retinal volume decreased by 0.8 and 0.4 mm3, respectively (adjusted mean difference: 0.3 mm3, 95% confidence interval 0.02 to 0.53 mm3, P=0.03). At 12 months, the mean change in visual acuity was 0 letters in the mETDRS group and 2 letters worse in the MMG group (adjusted mean difference: 2 letters, 95% confidence interval −0.5 to 5 letters, P=0.10). Conclusions At 12 months after treatment, the MMG technique is less effective at reducing OCT measured retinal thickening than the

  8. Volcano like pattern in optical coherence tomography in chronic diabetic macular edema.

    PubMed

    Pai, Sivakami A; Hussain, Nazimul; Hebri, Sudhira P; Lootah, Afra M; Dekhain, Moza A

    2014-04-01

    In this article we herein report an interesting vitreo-macular interface abnormality associated with chronic diabetic cystoid macular edema. It is an observational case study of three diabetic patients examined in the diabetic clinic. All the patients had proliferative diabetic retinopathy with chronic macular edema. A serial cross sectional OCT examination and tracking of both the longitudinal progression of macular thickening and vitreo-macular interface revealed cystoid macular edema with a characteristic hyperreflective vitreous shadow emerging from the vitreofoveal interface. All the patients had dehiscence of inner retinal layers. This particular morphological feature at the vitreo-foveolar interface, which we name as "volcano sign", has not been described earlier. The probable mechanism of such a finding probably could be due to slow progressive leakage of chronic cytoid fluid into the vitreous with condensation of the overlying vitreous. Vitreo-macular traction followed by posterior vitreous detachment probably would have contributed to such a morphological event.

  9. Volcano like pattern in optical coherence tomography in chronic diabetic macular edema.

    PubMed

    Pai, Sivakami A; Hussain, Nazimul; Hebri, Sudhira P; Lootah, Afra M; Dekhain, Moza A

    2014-04-01

    In this article we herein report an interesting vitreo-macular interface abnormality associated with chronic diabetic cystoid macular edema. It is an observational case study of three diabetic patients examined in the diabetic clinic. All the patients had proliferative diabetic retinopathy with chronic macular edema. A serial cross sectional OCT examination and tracking of both the longitudinal progression of macular thickening and vitreo-macular interface revealed cystoid macular edema with a characteristic hyperreflective vitreous shadow emerging from the vitreofoveal interface. All the patients had dehiscence of inner retinal layers. This particular morphological feature at the vitreo-foveolar interface, which we name as "volcano sign", has not been described earlier. The probable mechanism of such a finding probably could be due to slow progressive leakage of chronic cytoid fluid into the vitreous with condensation of the overlying vitreous. Vitreo-macular traction followed by posterior vitreous detachment probably would have contributed to such a morphological event. PMID:24843311

  10. Volcano like pattern in optical coherence tomography in chronic diabetic macular edema

    PubMed Central

    Pai, Sivakami A.; Hussain, Nazimul; Hebri, Sudhira P.; Lootah, Afra M.; Dekhain, Moza A.

    2014-01-01

    In this article we herein report an interesting vitreo-macular interface abnormality associated with chronic diabetic cystoid macular edema. It is an observational case study of three diabetic patients examined in the diabetic clinic. All the patients had proliferative diabetic retinopathy with chronic macular edema. A serial cross sectional OCT examination and tracking of both the longitudinal progression of macular thickening and vitreo-macular interface revealed cystoid macular edema with a characteristic hyperreflective vitreous shadow emerging from the vitreofoveal interface. All the patients had dehiscence of inner retinal layers. This particular morphological feature at the vitreo-foveolar interface, which we name as “volcano sign”, has not been described earlier. The probable mechanism of such a finding probably could be due to slow progressive leakage of chronic cytoid fluid into the vitreous with condensation of the overlying vitreous. Vitreo-macular traction followed by posterior vitreous detachment probably would have contributed to such a morphological event. PMID:24843311

  11. Macular morphology and response to ranibizumab treatment in patients with wet age-related macular degeneration

    PubMed Central

    Dervenis, Nikolaos; Younis, Saad

    2016-01-01

    Purpose The purpose of this study was to assess whether specific characteristics of spectral domain optical coherence tomography (SD-OCT) affect structural and functional outcomes and number of injections needed in ranibizumab (0.05 mL of 10 mg/mL Lucentis solution)-treated wet age-related macular degeneration (AMD) patients. Patients and methods This retrospective case series included 62 newly diagnosed wet AMD patients treated with three monthly intravitreal ranibizumab injections followed by monthly follow-up and pro re nata retreatment. The presence of dome-shaped pigment epithelial detachment (PED), disruption of the retinal pigment epithelium (RPE), and subretinal and intraretinal fluid was associated with changes in Early Treatment of Diabetic Retinopathy Study visual acuity, central macular thickness (CMT), and number of injections needed during the 6-month follow-up. Results The presence of PED was associated with lower values of CMT at presentation (399 μm [±132 μm] vs 310 μm [±51 μm], P=0.005). The presence of RPE disruption was associated with worse visual acuity in month 6 (0.36 [±0.22] vs 0.61 [0.45], P=0.027) and fewer injections (4.23 [±0.92] vs 3.55 [±0.60], P=0.007). The presence of intraretinal fluid at presentation was associated with worse visual acuity outcomes in month 4 (P=0.045) but not in month 6. Conclusion The dome-shaped PED was associated with lower CMT at presentation, but it did not affect response to treatment. RPE disruption was associated with worse functional outcomes with fewer injections. Intraretinal fluid at presentation may suggest delayed response to treatment. Individualized SD-OCT analysis could lead to individualized approach to wet AMD patients. SD-OCT can offer imaging biomarkers to assess the prognosis of anti-VEGF treatment in AMD patients. PMID:27366051

  12. Awareness, Knowledge, and Concern about Age-Related Macular Degeneration

    ERIC Educational Resources Information Center

    Cimarolli, Verena R.; Laban-Baker, Allie; Hamilton, Wanda S.; Stuen, Cynthia

    2012-01-01

    Age-related macular degeneration (AMD)--a common eye disease causing vision loss--can be detected early through regular eye-health examinations, and measures can be taken to prevent visual decline. Getting eye examinations requires certain levels of awareness, knowledge, and concern related to AMD. However, little is known about AMD-related…

  13. The Experience of Age-Related Macular Degeneration

    ERIC Educational Resources Information Center

    Wong, Elaine Y. H.; Guymer, Robyn H.; Hassell, Jennifer B.; Keeffe, Jill E.

    2004-01-01

    This qualitative article describes the impact of age-related macular degeneration (ARMD) among 15 participants: how a person makes sense of ARMD, the effect of ARMD on the person's quality of life, the psychological disturbances associated with the limitations of ARMD, and the influence of ARMD on social interactions. Such in-depth appreciation of…

  14. Technology needs for tomorrow's treatment and diagnosis of macular diseases

    NASA Astrophysics Data System (ADS)

    Soubrane, Gisèle

    2008-02-01

    Retinal imaging is the basis of macular disease's diagnosis. Currently available technologies in clinical practice are fluorescein and indocyanin green (ICG) angiographies, in addition to optical coherence tomography (OCT), which is an in vivo "histology-like" cross-sectional images of the retina. Recent developments in the field of OCT imaging include Spectral-Domain OCT. However OCT remains a static view of the macula with no direct link with dynamic observation obtained by angiographies. Adaptative optics is an encouraging perspective for fundus analysis in the future, and could be linked to OCT or angiographies. Treatments of macular disease have exploded these past few years. Pharmacologic inhibition of angiogenesis represents a novel approach in the treatment of choroidal neovascularization in eyes with age-related macular degeneration. The major action explored is the direct inhibition of the protein VEGF with antibody-like products. New anti-VEGF drugs are in development aiming at the VEGF receptors or synthesis of VEGF. But various components of the neovascular cascade, including growth factor expression, extracellular matrix modulation, integrin inhibition represent potential targets for modulation with drugs. Intra-vitreal injections are nowadays the main route of administration for these new treatments but they are potentially responsible of side effects such as endophtalmitis. Development of other routes of treatment would require new formulation of used drugs. The improvement of retinal imaging leads to a better understanding of macular disease mechanisms and will help to develop new routes and targets of treatment.

  15. Macular infarction in a patient with Toxoplasma retinochoroditis.

    PubMed

    Kumar, Vinod; Takkar, Brijesh; Chandra, Parijat; Kumar, Atul

    2016-01-11

    Toxoplasma retinochoroditis is one of the commonest causes of infectious posterior uveitis and may lead to occlusive retinitis. We present a case of a patient with Toxoplasma retinochoroditis who developed macular infarction after initial improvement on pharmacotherapy. The potential aetiology and outcome are described.

  16. Non-invasive in vivo measurement of macular carotenoids

    NASA Technical Reports Server (NTRS)

    Lambert, James L. (Inventor); Borchert, Mark S. (Inventor)

    2009-01-01

    A non-invasive in vivo method for assessing macular carotenoids includes performing Optical Coherence Tomography (OCT) on a retina of a subject. A spatial representation of carotenoid levels in the macula based on data from the OCT of the retina can be generated.

  17. Nutritional modulation of age-related macular degeneration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Age-related macular degeneration (AMD) is the leading cause of blindness in the elderly worldwide. It affects 30-50 million individuals and clinical hallmarks of AMD are observed in at least one third of persons over the age of 75 in industrialized countries (Gehrs et al., 2006). Costs associated wi...

  18. Idiopathic eruptive macular pigmentation with papillomatosis (IEMPP): A controversial entity.

    PubMed

    Pang, Y Z; Koh, W L; Ang, C C

    2016-01-01

    A 19-year-old man with a 6-month history of progressive development of hyperpigmented, velvety plaques on the face and body. A diagnosis of idiopathic eruptive macular pigmentation with papillomatosis (IEMPP) was determined. This entity is discussed. PMID:27617467

  19. Dumb holes: analogues for black holes.

    PubMed

    Unruh, W G

    2008-08-28

    The use of sonic analogues to black and white holes, called dumb or deaf holes, to understand the particle production by black holes is reviewed. The results suggest that the black hole particle production is a low-frequency and low-wavenumber process.

  20. Loculated fluid. A previously undescribed fluorescein angiographic finding in choroidal neovascularization associated with macular degeneration. Macular Photocoagulation Study Reading Center.

    PubMed

    Bressler, N M; Bressler, S B; Alexander, J; Javornik, N; Fine, S L; Murphy, R P

    1991-02-01

    The Foveal Photocoagulation Study, a component of the Macular Photocoagulation Study, is designed to evaluate whether laser treatment can reduce the risk of severe visual loss in eyes with well-defined choroidal neovascular membranes associated with macular degeneration that extend through the foveal center. On one third of the 554 baseline angiograms of study patients enrolled in and whose eyes were graded in the study as of January 31, 1990, the Reading Center staff has noted an unusual pattern of hyperfluorescence in the late-transit frames that has not been described previously. This pattern, which we call "loculated fluid," consists of a well-demarcated area of hyperfluorescence that appears to represent pooling of fluorescein in a compartmentalized space anterior to the choroidal neovascular leakage. Although the loculated fluid may conform to a pattern of typical cystoid macular edema, it can also pool within an area deep to the sensory retina in a shape that does not bear any resemblance to cystoid macular edema. This pattern is important to recognize because it (1) should not be confused with the angiographic pattern or extent of choroidal neovascularization and (2) should be differentiated from a serous detachment or tear of the retinal pigment epithelium.

  1. Statins for age-related macular degeneration

    PubMed Central

    Gehlbach, Peter; Li, Tianjing; Hatef, Elham

    2016-01-01

    Background Age-related macular degeneration (AMD) is a progressive late onset disorder of the macula affecting central vision. Age-related macular degeneration is the leading cause of blindness in people over 65 years in industrialized countries. Recent epidemiologic, genetic, and pathological evidence has shown AMD shares a number of risk factors with atherosclerosis, leading to the hypothesis that statins may exert protective effects in AMD. Objectives The objective of this review was to examine the effectiveness of statins compared with other treatments, no treatment, or placebo in delaying the onset and progression of AMD. Search methods We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (2014, Issue 6), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to June 2014), EMBASE (January 1980 to June 2014), Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to June 2014), PubMed (January 1946 to June 2014), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov), and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 5 June 2014. Selection criteria We included randomized controlled trials (RCTs) that compared statins with other treatments, no treatment, or placebo in participants who were either susceptible to or diagnosed as having early stages of AMD. Data collection and analysis We used standard methodological procedures expected by The Cochrane Collaboration. Two authors independently evaluated the search results against the selection criteria, abstracted data, and assessed risk of bias. We did not perform meta-analysis due to heterogeneity in the interventions and outcomes among the

  2. Statins for age-related macular degeneration

    PubMed Central

    Gehlbach, Peter; Li, Tianjing; Hatef, Elham

    2016-01-01

    Background Age-related macular degeneration (AMD) is a progressive late onset disorder of the macula affecting central vision. Age-related macular degeneration is the leading cause of blindness in people over 65 years in industrialized countries. Recent epidemiologic, genetic, and pathological evidence has shown AMD shares a number of risk factors with atherosclerosis, leading to the hypothesis that statins may exert protective effects in AMD. Objectives The objective of this review was to examine the effectiveness of statins compared with other treatments, no treatment, or placebo in delaying the onset and progression of AMD. Search methods We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (2014, Issue 6), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to June 2014), EMBASE (January 1980 to June 2014), Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to June 2014), PubMed (January 1946 to June 2014), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov), and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 5 June 2014. Selection criteria We included randomized controlled trials (RCTs) that compared statins with other treatments, no treatment, or placebo in participants who were either susceptible to or diagnosed as having early stages of AMD. Data collection and analysis We used standard methodological procedures expected by The Cochrane Collaboration. Two authors independently evaluated the search results against the selection criteria, abstracted data, and assessed risk of bias. We did not perform meta-analysis due to heterogeneity in the interventions and outcomes among the

  3. Emerging therapies for the treatment of neovascular age-related macular degeneration and diabetic macular edema.

    PubMed

    Emerson, M Vaughn; Lauer, Andreas K

    2007-01-01

    Diabetic macular edema (DME) and choroidal neovascularization (CNV) associated with age-related macular degeneration (AMD) are the leading causes of vision loss in the industrialized world. The mainstay of treatment for both conditions has been thermal laser photocoagulation, while there have been recent advances in the treatment of CNV using photodynamic therapy with verteporfin. While both of these treatments have prevented further vision loss in a subset of patients, vision improvement is rare. Anti-vascular endothelial growth factor (VEGF)-A therapy has revolutionized the treatment of both conditions. Pegaptanib, an anti-VEGF aptamer, prevents vision loss in CNV, although the performance is similar to that of photodynamic therapy. Ranibizumab, an antibody fragment, and bevacizumab, a full-length humanized monoclonal antibody against VEGF, have both shown promising results, with improvements in visual acuity in the treatment of both diseases. VEGF trap, a modified soluble VEGF receptor analog, binds VEGF more tightly than all other anti-VEGF therapies, and has also shown promising results in early trials. Other treatment strategies to decrease the effect of VEGF have used small interfering RNA to inhibit VEGF production and VEGF receptor production. Corticosteroids have shown efficacy in controlled trials, including anacortave acetate in the treatment and prevention of CNV, and intravitreal triamcinolone acetonide and the fluocinolone acetonide implant in the treatment of DME. Receptor tyrosine kinase inhibitors, such as vatalanib, inhibit downstream effects of VEGF, and have been effective in the treatment of CNV in early studies. Squalamine lactate inhibits plasma membrane ion channels with downstream effects on VEGF, and has shown promising results with systemic administration. Initial results are also encouraging for other growth factors, including pigment epithelium-derived factor administered via an adenoviral vector. Ruboxistaurin, which decreases protein

  4. Macular Structure and Function in Nonhuman Primate Experimental Glaucoma

    PubMed Central

    Wilsey, Laura J.; Reynaud, Juan; Cull, Grant; Burgoyne, Claude F.; Fortune, Brad

    2016-01-01

    Purpose To evaluate structure and function of macular retinal layers in nonhuman primate (NHP) experimental glaucoma (EG). Methods Twenty-one NHP had longitudinal imaging of macular structure by SDOCT, 16 also had recordings of function by multifocal ERG. The average thickness over 15° was derived for seven individual SDOCT layers: macular nerve fiber layer (m-NFL), retinal ganglion cell layer (RGCL), inner plexiform layer (IPL), inner nuclear layer (INL), outer plexiform layer (OPL), outer nuclear layer+inner segments combined (ONL+IS), and outer segments (OS). Peripapillary RNFL thickness (ppRNFLT) was measured from a single circular B-scan with 12° diameter. Responses to a slow-sequence multifocal ERG (mfERG) stimulus (7F) were filtered (at 75 Hz) into low- and high-frequency components (LFC, HFC). Results At final follow-up, significant structural loss occurred only in EG eyes and only for ppRNFLT (−29 ± 23%), m-NFL (−17 ± 16%), RGCL (−22 ± 15%), and IPL (−19 ± 14%); though there was also a small increase in OPL (+6 ± 7%) and ONL+IS (4 ± 4%) and a similar tendency for INL. Macular structural loss was correlated with ppRNFLT only for the NFL, RGCL and IPL (R = 0.95, 0.93 and 0.95, respectively, P < 0.0001). Significant functional loss occurred only for HFC and N2 in EG eyes. Significant longitudinal structure–function correlations (P < 0.01) were observed only in EG eyes and only for mfERG HFC and N2: HFC was correlated with ppRNFLT (R = 0.69), macular NFL (R = 0.67), RGCL (R = 0.74), and IPL (R = 0.72); N2 was correlated with RGCL (R = 0.54) and IPL (R = 0.48). High-frequency components amplitude change was inversely correlated with outer retinal thickness change (= −0.66). Conclusions Macular structural and functional losses are correlated and specific to ganglion cells over a wide range of EG severity. Outer retinal changes are likely due to inner retinal loss. PMID:27082305

  5. Computer-assisted three-dimensional reconstruction and simulations of vestibular macular neural connectivities

    NASA Technical Reports Server (NTRS)

    Ross, Muriel D.; Chimento, Thomas; Doshay, David; Cheng, Rei

    1992-01-01

    Results of computer-assisted research concerned with the three-dimensional reconstruction and simulations of vestibular macular neural connectivities are summarized. The discussion focuses on terminal/receptive fields, the question of synapses across the striola, endoplasmic reticulum and its potential role in macular information processing, and the inner epithelial plexus. Also included are preliminary results of computer simulations of nerve fiber collateral functioning, an essential step toward the three-dimensional simulation of a functioning macular neural network.

  6. Macular sub-layer thinning and association with pulmonary function tests in Amyotrophic Lateral Sclerosis.

    PubMed

    Simonett, Joseph M; Huang, Russell; Siddique, Nailah; Farsiu, Sina; Siddique, Teepu; Volpe, Nicholas J; Fawzi, Amani A

    2016-01-01

    Amyotrophic Lateral Sclerosis (ALS) is a complex neurodegenerative disorder that may have anterior visual pathway involvement. In this study, we compare the macular structure of patients with ALS to healthy controls, and examine correlations between macular sub-layer thickness measurements and pulmonary function tests and disease duration. ALS patients underwent optical coherence tomography (OCT) imaging to obtain macular cube scans of the right eye. Macular cube OCT data from age-matched healthy subjects were provided by the OCT reading center. Semi-automated retinal segmentation software was used to quantify macular sub-layers. Pulmonary function tests and time since symptom onset were collected retrospectively from the electronic medical records of ALS patients. Macular retinal nerve fiber layer was significantly thinner in ALS patients compared to healthy controls (P < 0.05). Total macular and other sub-layer thicknesses were not reduced in the ALS cohort. Macular retinal nerve fiber layer thickness positively correlated with forced vital capacity % predicted and forced expiratory volume in 1 second % predicted (P < 0.05). In conclusion, analysis of OCT measurements supports the involvement of the anterior visual pathway in ALS. Subtle structural thinning in the macular retinal nerve fiber layer correlates with pulmonary function tests. PMID:27383525

  7. Macular sub-layer thinning and association with pulmonary function tests in Amyotrophic Lateral Sclerosis

    PubMed Central

    Simonett, Joseph M.; Huang, Russell; Siddique, Nailah; Farsiu, Sina; Siddique, Teepu; Volpe, Nicholas J.; Fawzi, Amani A.

    2016-01-01

    Amyotrophic Lateral Sclerosis (ALS) is a complex neurodegenerative disorder that may have anterior visual pathway involvement. In this study, we compare the macular structure of patients with ALS to healthy controls, and examine correlations between macular sub-layer thickness measurements and pulmonary function tests and disease duration. ALS patients underwent optical coherence tomography (OCT) imaging to obtain macular cube scans of the right eye. Macular cube OCT data from age-matched healthy subjects were provided by the OCT reading center. Semi-automated retinal segmentation software was used to quantify macular sub-layers. Pulmonary function tests and time since symptom onset were collected retrospectively from the electronic medical records of ALS patients. Macular retinal nerve fiber layer was significantly thinner in ALS patients compared to healthy controls (P < 0.05). Total macular and other sub-layer thicknesses were not reduced in the ALS cohort. Macular retinal nerve fiber layer thickness positively correlated with forced vital capacity % predicted and forced expiratory volume in 1 second % predicted (P < 0.05). In conclusion, analysis of OCT measurements supports the involvement of the anterior visual pathway in ALS. Subtle structural thinning in the macular retinal nerve fiber layer correlates with pulmonary function tests. PMID:27383525

  8. Vitrectomy for bilateral macular schisis without apparent optic disc anomalies

    PubMed Central

    Andonegui, José; Maya, José Ramón; Echeverría, Marta; Alcaine, Araceli

    2016-01-01

    A 78-year-old man complained of bilateral visual acuity loss. Optical coherence tomography examination showed bilateral macular schisis with fluid accumulation in the external retinal layers without vitreous traction. Fundus examination and fluorescein angiography were normal in both eyes. Both eyes were treated by phacoemulsification, intraocular lens implantation, and vitrectomy without laser, gas exchange, or retinal fenestration. Slow and progressive fluid resorption and improvement in VA were observed in both eyes. Macular schisis similar to the one associated with optic disc anomalies is a possibility in patients without apparent disc anomalies. Vitrectomy without laser, gas, or retinal fenestration may be a good therapeutic option even in patients with a PVD preoperatively. PMID:27703873

  9. The genetics of age-related macular degeneration.

    PubMed

    Gorin, M B; Breitner, J C; De Jong, P T; Hageman, G S; Klaver, C C; Kuehn, M H; Seddon, J M

    1999-11-01

    Age-related macular degeneration (AMD) is increasingly recognized as a complex genetic disorder in which one or more genes contribute to an individual's susceptibility for developing the condition. Twin and family studies as well as population-based genetic epidemiologic methods have convincingly demonstrated the importance of genetics in AMD, though the extent of heritability, the number of genes involved, and the phenotypic and genetic heterogeneity of the condition remain unresolved. The extent to which other hereditary macular dystrophies such as Stargardts disease, familial radial drusen (malattia leventinese), Best's disease, and peripherin/RDS-related dystrophy are related to AMD remains unclear. Alzheimer's disease, another late onset, heterogeneous degenerative disorder of the central nervous system, offers a valuable model for identifying the issues that confront AMD genetics.

  10. Prediction of visual acuity recovery in cystoid macular edema.

    PubMed

    McDonnell, P J; Ryan, S J; Walonker, A F; Miller-Scholte, A

    1992-05-01

    Three consecutive patients participated in a prospective evaluation of pseudophakic cystoid macular edema. The duration of the macular edema ranged from 6 to 8 months. On the initial visit, the best corrected acuity with spectacles was determined and a potential acuity meter reading was obtained; this test suggested potential for visual recovery in two of the three patients. Sub-tenon's injections of methylprednisolone acetate (20 mg) were administered along with topical 1% prednisolone acetate and 1% atropine. One month later, visual acuity was improved by more than 2 Snellen lines in all three of the patients. A visual acuity measurement with the potential acuity meter that is better than the best corrected acuity with spectacles may reflect the presence of intact, but dysfunctional photoreceptors that are capable of restoring visual acuity upon resolution of the edema.

  11. Mutations in IMPG1 Cause Vitelliform Macular Dystrophies

    PubMed Central

    Manes, Gaël; Meunier, Isabelle; Avila-Fernández, Almudena; Banfi, Sandro; Le Meur, Guylène; Zanlonghi, Xavier; Corton, Marta; Simonelli, Francesca; Brabet, Philippe; Labesse, Gilles; Audo, Isabelle; Mohand-Said, Saddek; Zeitz, Christina; Sahel, José-Alain; Weber, Michel; Dollfus, Hélène; Dhaenens, Claire-Marie; Allorge, Delphine; De Baere, Elfride; Koenekoop, Robert K.; Kohl, Susanne; Cremers, Frans P.M.; Hollyfield, Joe G.; Sénéchal, Audrey; Hebrard, Maxime; Bocquet, Béatrice; Ayuso García, Carmen; Hamel, Christian P.

    2013-01-01

    Vitelliform macular dystrophies (VMD) are inherited retinal dystrophies characterized by yellow, round deposits visible upon fundus examination and encountered in individuals with juvenile Best macular dystrophy (BMD) or adult-onset vitelliform macular dystrophy (AVMD). Although many BMD and some AVMD cases harbor mutations in BEST1 or PRPH2, the underlying genetic cause remains unknown for many affected individuals. In a large family with autosomal-dominant VMD, gene mapping and whole-exome sequencing led to the identification of a c.713T>G (p.Leu238Arg) IMPG1 mutation, which was subsequently found in two other families with autosomal-dominant VMD and the same phenotype. IMPG1 encodes the SPACR protein, a component of the rod and cone photoreceptor extracellular matrix domains. Structural modeling indicates that the p.Leu238Arg substitution destabilizes the conserved SEA1 domain of SPACR. Screening of 144 probands who had various forms of macular dystrophy revealed three other IMPG1 mutations. Two individuals from one family affected by autosomal-recessive VMD were homozygous for the splice-site mutation c.807+1G>T, and two from another family were compound heterozygous for the mutations c.461T>C (p.Leu154Pro) and c.1519C>T (p.Arg507∗). Most cases had a normal or moderately decreased electrooculogram Arden ratio. We conclude that IMPG1 mutations cause both autosomal-dominant and -recessive forms of VMD, thus indicating that impairment of the interphotoreceptor matrix might be a general cause of VMD. PMID:23993198

  12. Geriatric vision loss due to cataracts, macular degeneration, and glaucoma.

    PubMed

    Eichenbaum, Joseph W

    2012-01-01

    The major causes of impaired vision in the elderly population of the United States are cataracts, macular degeneration, and open-angle glaucoma. Cataracts and macular degeneration usually reduce central vision, especially reading and near activities, whereas chronic glaucoma characteristically attacks peripheral vision in a silent way, impacting balance, walking, and driving. Untreated, these visual problems lead to issues with regard to taking medications, keeping track of finances and personal information, walking, watching television, and attending the theater, and often create social isolation. Thus, visually impaired individuals enter nursing homes 3 years earlier, have twice the risk of falling, and have 4× the risk of hip fracture. Consequently, many elderly with low vision exercise greater demands on community services. With the prospect of little improvement and sustained visual loss, in the face of poor tolerance of low-vision services and not accepting magnification as the only way to read, clinical depression is common. In many instances, however, early and accurate diagnosis can result in timely treatment and can preserve quality of life. This review will look at current diagnostic and therapeutic considerations. Currently, about 20.5 million people in the United States have cataracts. The number will reach 30 million by 2020. About 1.75 million Americans currently have some form of macular degeneration, and the number is estimated to increase to 2.95 million in 2020. Approximately 2.2 million Americans have glaucoma, and by 2020 that number is estimated to be close to 3.4 million people. It is projected that by 2030 there will be 72.1 million seniors. With some overlap of the above 3 groups conservatively estimated (if you add the 2030 cataract group to the macular degeneration and glaucoma groups), then about 1 in 2 senior individuals by 2030 may have some significant ocular disease, which could account for about 50% of the healthcare budget for the

  13. Smoking and Age-Related Macular Degeneration: Review and Update

    PubMed Central

    Velilla, Sara; García-Medina, José Javier; García-Layana, Alfredo; Pons-Vázquez, Sheila; Pinazo-Durán, M. Dolores; Gómez-Ulla, Francisco; Arévalo, J. Fernando; Díaz-Llopis, Manuel; Gallego-Pinazo, Roberto

    2013-01-01

    Age-related macular degeneration (AMD) is one of the main socioeconomical health issues worldwide. AMD has a multifactorial etiology with a variety of risk factors. Smoking is the most important modifiable risk factor for AMD development and progression. The present review summarizes the epidemiological studies evaluating the association between smoking and AMD, the mechanisms through which smoking induces damage to the chorioretinal tissues, and the relevance of advising patients to quit smoking for their visual health. PMID:24368940

  14. Grid photocoagulation improves reading ability in diffuse diabetic macular oedema.

    PubMed

    McNaught, E I; Foulds, W S; Allan, D

    1988-01-01

    Forty-eight patients with diffuse diabetic macular oedema were treated with perifoveal blue/green Argon 'grid' laser photocoagulation. Clinical assessment of patients was supported by serial fluorescein angiography. Patients were followed up for one year after treatment, and a two year follow-up was obtained in 29 patients. Statistical analysis showed no significant improvement in distance acuity, but demonstrated clear benefit as regards reading ability.

  15. Macular oedema due to letrozole: a first case report.

    PubMed

    Moschos, Marilita M; Chatziralli, Irini P; Zagouri, Flora; Zografos, George C

    2012-11-01

    A 72-year-old woman presented with unexplained, progressive, painless visual loss in the right eye during the past six months. At presentation visual acuity (VA) was 3/60 in the right eye and 6/6 in the left eye. Anterior segment examination and intraocular pressures were normal. Dilated fundoscopy revealed significant macular oedema in the right eye and a normal fundus appearance in the left eye. Her medical history was noteworthy for breast ductal carcinoma in situ, for which she had undergone right mastectomy three years earlier. She had not received chemotherapy or radiotherapy but she had been under treatment with letrozole 2.5 mg/day over the past three years. She did not receive any other medication. Optical coherence tomography showed intraretinal fluid and a significant increase in retinal thickness in the foveal and parafoveal areas, while fluorescein angiography detected foveal hyperfluorescence and leakage of the dye in the late phase. Multifocal electroretinogram showed a decreased response in both eyes. In suspicion of letrozole-related retinopathy, the patient was advised to stop the medication. The patient agreed to receive an intravitreal injection of 0.05 ml/0.5 mg ranibizumab. One month later, VA in the right eye was 6/9 and macular oedema had apparently improved. This is the first reported case of letrozole-associated macular oedema treated with intravitreal ranibizumab.

  16. Multifocal electroretinography in patients with Stargardt's macular dystrophy

    PubMed Central

    Kretschmann, U; Seeliger, M; Ruether, K; Usui, T; Apfelstedt-Sylla, E; Zrenner, E

    1998-01-01

    AIMS—To describe the topography of multifocal electroretinograms (ERGs) and to explore its diagnostic value in patients with Stargardt's macular dystrophy (SMD).
METHODS—51 patients with SMD were examined by means of the m-sequence technique to characterise the topography of electroretinographic responses in the central visual field. The results were compared with data from 30 normal volunteers.
RESULTS—In 49 of 51 patients with SMD, macular electroretinographic activity was markedly diminished or non-detectable. Towards more peripheral areas, ERG responses of the SMD patients approached those of normals. Implicit times were not markedly delayed at any eccentricity.
CONCLUSION—In contrast with Ganzfeld electroretinography, multifocal electroretinography is useful to detect foveal dysfunction in SMD. Areas of dysfunction were found to be usually larger than expected from psychophysical measurements and morphological alteration. In early stages of the disease it was possible to detect foveal dysfunction, even in patients lacking morphological fundus changes and with good visual acuity.

 Keywords: Stargardt's macular dystrophy; fundus flavimaculatus; electroretinography PMID:9602623

  17. Comparison of intravitreal bevacizumab with macular photocoagulation for treatment of diabetic macular edema: a systemic review and Meta-analysis

    PubMed Central

    Liu, Xiang-Dong; Zhou, Xiao-Dong; Wang, Zhi; Shen, Hong-Jie

    2014-01-01

    AIM To further evaluate the efficacy and safety of intravitreal bevacizumab (IVB) versus macular photocoagulation (MPC) in treatment of diabetic macular edema (DME) by Meta-analysis. METHODS Pertinent publications were identified through systemic searches of PubMed, Medline, EMBASE, and the Cochrane Controlled Trials Register up to 30 November, 2013. Changes in central macular thickness (CMT) in µm and best-corrected visual acuity (BCVA) in logMAR equivalents were extracted at 1, 3, 6, 12 and 24mo after initial treatment, and a Meta-analysis was carried out to compare results between groups receiving IVB and MPC. RESULTS Five randomized controlled trial (RCTs) and one high-quality comparative study were identified and included. Our Meta-analysis revealed that both IVB and MPC resulted in the improvements of CMT and BCVA in eyes with DME at 1mo after initial treatment, with IVB being significantly superior to MPC (P=0.01 and 0.02, respectively). The improvements of both measure outcomes at 3, 6, 12 and 24mo after treatment did not vary significantly between the IVB groups and MPC groups (CMT at 3mo, P=0.85; at 6mo, P=0.29; at 12mo, P=0.56; at 24mo, P=0.71; BCVA at 3mo, P=0.31; at 6mo, P= 0.30; at 12mo, P=0.23; at 24mo, P=0.52). However, the number of observed adverse events was low in all studies. CONCLUSION Current evidence shows IVB treatment trends to be more effective in improvements of macular edema and vision in eyes with DME at an earlier follow up (1mo) compared with MPC. At other time, both interventions have comparable efficacy without statistical significances. PMID:25540764

  18. Deburring small intersecting holes

    SciTech Connect

    Gillespie, L.K.

    1980-08-01

    Deburring intersecting holes is one of the most difficult deburring tasks faced by many industries. Only 14 of the 37 major deburring processes are applicable to most intersecting hole applications. Only five of these are normally applicable to small or miniature holes. Basic process capabilities and techniques used as a function of hole sizes and intersection depths are summarized.

  19. Hole-Aligning Tool

    NASA Technical Reports Server (NTRS)

    Collins, Frank A.; Saude, Frank; Sep, Martin J.

    1996-01-01

    Tool designed for use in aligning holes in plates or other structural members to be joined by bolt through holes. Holes aligned without exerting forces perpendicular to planes of holes. Tool features screw-driven-wedge design similar to (but simpler than) that of some automotive exhaust-pipe-expanding tools.

  20. Macular pigment optical density is related to serum lutein in retinitis pigmentosa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Purpose: To determine whether macular pigment optical density (MPOD) is related to the degree of cystoid macular edema (CME) in patients with retinitis pigmentosa. Methods: We measured MPOD with heterochromatic flicker photometry and central foveal retinal thickness with optical coherence tomography...

  1. Macular lutein and zeaxanthin are related to brain lutein and zeaxanthin in primates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The xanthophyll pigments lutein and zeaxanthin cross the blood-retina barrier to preferentially accumulate in the macular region of the neural retina. There they form macular pigment, protecting the retina from blue light damage and oxidative stress. Lutein and zeaxanthin also accumulate in brain t...

  2. Intraoperative electrophysiological evaluations of macular function during peripheral scleral indentation

    PubMed Central

    Akiyama, Goichi; Matsumoto, Celso Soiti; Shinoda, Kei; Terauchi, Gaku; Matsumoto, Harue; Watanabe, Emiko; Iwata, Takeshi; Mizota, Atsushi; Miyake, Yozo

    2016-01-01

    Scleral indentation is widely used to examine the peripheral fundus, however it can increase the intraocular pressure (IOP) to high levels which can then affect retinal function. We evaluated the effects of scleral indentation on the macular function electrophysiologically. Intraoperative focal macular electroretinograms (iFMERGs) were recorded with and without controlling the IOP in 7 eyes. Without IOP control, the IOP increased from 21.7 ± 4.9 to 92.7 ± 20.2 mmHg significantly (P = 0.020) and the amplitudes of the b-wave (from 6.29 ± 1.160 to 3.71 ± 1.98 uV, P = 0.007), on-photopic negative response (from 2.29 ± 0.99 to 0.72 ± 0.47 uV, on-PhNR, P = 0.005), and d-wave (from 2.57 ± 0.41 to 1.64 ± 0.69 uV, P = 0.007) decreased significantly soon after beginning the indentation. All values returned to the baseline levels after releasing the indentation. In the eyes with IOP controlled, the IOP and the amplitude of all components did not change significantly during and after the indentation except the on-PhNR amplitude which was significantly reduced during the indentation. The changes in the iFMERGs and macular function caused by scleral indentation were transient and reversible. The changes can be minimized by controlling the IOP. PMID:27762313

  3. Inflammation and Macular Oedema after Pars Plana Vitrectomy

    PubMed Central

    Romano, Vito; Angi, Martina; del Grosso, Renata; Romano, Davide; Vinciguerra, Paolo; Romano, Mario R.

    2013-01-01

    Cystoid macular oedema (CMO) is a major cause of reduced vision following intraocular surgery. Although the aetiology of CMO is not completely clarified, intraocular inflammation is known to play a major role in its development. The macula may develop cytotoxic oedema when the primary lesion and fluid accumulation occur in the parenchymatous cells (intracellular oedema) or vasogenic oedema when the primary defect occurs in the blood-retinal barrier and leads to extracellular fluid accumulation (extracellular oedema). We report on the mechanisms of CMO formation after pars plana vitrectomy and associated surgical procedures and discuss possible therapeutic approaches. PMID:24288446

  4. [Diagnostic Criteria for Atrophic Age-related Macular Degeneration].

    PubMed

    Takahashi, Kanji; Shiraga, Fumio; Ishida, Susumu; Kamei, Motohiro; Yanagi, Yasuo; Yoshimura, Nagahisa

    2015-10-01

    Diagnostic criteria for dry age-related macular degeneration is described. Criteria include visual acuity, fundscopic findings, diagnostic image findings, exclusion criteria and classification of severity grades. Essential findings to make diagnosis as "geographic atrophy" are, 1) at least 250 μm in diameter, 2) round/oval/cluster-like or geographic in shape, 3) sharp delineation, 4) hypopigmentation or depigmentation in retinal pigment epithelium, 5) choroidal vessels are more visible than in surrounding area. Severity grades were classified as mild, medium and severe by relation of geographic atrophy to the fovea and attendant findings. PMID:26571627

  5. Dexamethasone intravitreal implant in the treatment of diabetic macular edema.

    PubMed

    Dugel, Pravin U; Bandello, Francesco; Loewenstein, Anat

    2015-01-01

    Diabetic macular edema (DME) resembles a chronic, low-grade inflammatory reaction, and is characterized by blood-retinal barrier (BRB) breakdown and retinal capillary leakage. Corticosteroids are of therapeutic benefit because of their anti-inflammatory, antiangiogenic, and BRB-stabilizing properties. Delivery modes include periocular and intravitreal (via pars plana) injection. To offset the short intravitreal half-life of corticosteroid solutions (~3 hours) and the need for frequent intravitreal injections, sustained-release intravitreal corticosteroid implants have been developed. Dexamethasone intravitreal implant provides retinal drug delivery for ≤6 months and recently has been approved for use in the treatment of DME. Pooled findings (n=1,048) from two large-scale, randomized Phase III trials indicated that dexamethasone intravitreal implant (0.35 mg and 0.7 mg) administered at ≥6-month intervals produced sustained improvements in best-corrected visual acuity (BCVA) and macular edema. Significantly more patients showed a ≥15-letter gain in BCVA at 3 years with dexamethasone intravitreal implant 0.35 mg and 0.7 mg than with sham injection (18.4% and 22.2% vs 12.0%). Anatomical assessments showed rapid and sustained reductions in macular edema and slowing of retinopathy progression. Phase II study findings suggest that dexamethasone intravitreal implant is effective in focal, cystoid, and diffuse DME, in vitrectomized eyes, and in combination with laser therapy. Ocular complications of dexamethasone intravitreal implant in Phase III trials included cataract-related events (66.0% in phakic patients), intraocular pressure elevation ≥25 mmHg (29.7%), conjunctival hemorrhage (23.5%), vitreous hemorrhage (10.0%), macular fibrosis (8.3%), conjunctival hyperemia (7.2%), eye pain (6.1%), vitreous detachment (5.8%), and dry eye (5.8%); injection-related complications (eg, retinal tear/detachment, vitreous loss, endophthalmitis) were infrequent (<2

  6. [Glaucoma and age-related macular degeneration intricacy].

    PubMed

    Valtot, F

    2008-07-01

    Age-related macular degeneration (AMD) is the leading cause of legal blindness among the elderly in Western nations. Age is also a well-known and well-evidenced risk factor for glaucoma. With increasing longevity and the rising prevalence of older people around the world, more and more patients will have glaucoma and AMD. Clinical evaluation of these patients still poses problems for clinicians. It is very important to order the right tests at the right time to distinguish glaucomatous defects from those caused by retinal lesions, because appropriate therapy has a beneficial effect on slowing or halting damage. PMID:18957915

  7. Multifocal fibrosclerosis associated with suprasellar and macular lesions.

    PubMed Central

    Brazier, D J; Sanders, M D

    1983-01-01

    Multifocal fibrosclerosis is a term used to denote a combination of similar fibrous disorders occurring at different anatomical sites and including idiopathic mediastinal and retroperitoneal fibrosis, sclerosing cholangitis, Riedel's thyroiditis, and orbital pseudotumour. This paper reports a patient, known to have retroperitoneal and testicular fibrosis, who suffered visual loss resulting from marked changes in the macular region of one eye and suprasellar extension of a mass in the pituitary fossa. These lesions appear to represent very uncommon manifestations of multifocal fibrosclerosis. Images PMID:6838800

  8. Age-Related Macular Degeneration: Advances in Management and Diagnosis

    PubMed Central

    Yonekawa, Yoshihiro; Miller, Joan W.; Kim, Ivana K.

    2015-01-01

    Age-related macular degeneration (AMD) is the most common cause of irreversible visual impairment in older populations in industrialized nations. AMD is a late-onset deterioration of photoreceptors and retinal pigment epithelium in the central retina caused by various environmental and genetic factors. Great strides in our understanding of AMD pathogenesis have been made in the past several decades, which have translated into revolutionary therapeutic agents in recent years. In this review, we describe the clinical and pathologic features of AMD and present an overview of current diagnosis and treatment strategies. PMID:26239130

  9. Squalamine lactate for exudative age-related macular degeneration.

    PubMed

    Connolly, Brian; Desai, Avinash; Garcia, Charles A; Thomas, Edgar; Gast, Michael J

    2006-09-01

    Squalamine lactate inhibits angiogenesis by a long-lived, intracellular mechanism of action. The drug is taken up into activated endothelial cells through caveolae, small invaginations in the cellular membrane. Subsequently, the drug binds to and "chaperones" calmodulin to an intracellular membrane compartment and blocks angiogenesis at several levels. A series of basic investigations, preclinical studies, and human clinical trials have begun to establish the proof of concept, efficacy, and safety parameters for use of squalamine lactate as a therapeutic agent for exudative age-related macular degeneration and several types of malignancies. PMID:16935213

  10. [The genetic variability of complement system in pathogenesis of age-related macular degeneration].

    PubMed

    Kubicka-Trząska, Agnieszka; Karska-Basta, Izabella; Dziedzina, Sylwia; Sanak, Marek

    2015-01-01

    Age-related macular degeneration is the leading cause of irreversible central vision impairment in people aged over 50 in developed countries. Age-related macular degeneration is a complex disease derived from environmental, immune and genetic factors. The complement pathway has been implicated in the pathogenesis of many diseases. Recently, variants in several genes, such as complement H (CFH), complement factor B (CFB), complement 2 (C2), and complement 3 (C3), encoding complement pathway proteins, have been identified as associated with age-related macular degeneration. However, the associations between these genes and age-related macular degeneration varied due to genetic variation within populations and various ethnics groups. The strongest association was found between the age-related macular degeneration and SNP Y402H rs 1061170 variant of CFH gene, which is present in 30% to 50% of age-related macular degeneration patients in Caucasian population and which is a risk factor for the development of age-related macular degeneration. Cohort studies showed that polymorphism Arg102Gly (SNP rs 2230199) of C3 protein could serve as a high-risk genetic marker for the development of age-related macular degeneration. Other rare variants of C3 (Lys155Gln, Lys65Gln, Arg735Trp, Ser1619Arg), may also be associated with a high incidence of age-related macular degeneration in some ethnic groups. A protective haplotype of variants E318D and IVS10 in the C2 gene as well as L9H and R320 in the BF were associated with age-related macular degeneration but only in Caucasians. The genetic findings in age-related macular degeneration patients stress the importance of detailed phenotyping to identify age-related macular degeneration subtypes, which may be associated with the presence of different polymorphisms and various environmental risk factors in any population. Further studies may be helpful to improve the effectiveness of prophylaxis and therapeutic options in age

  11. Nonstationary analogue black holes

    NASA Astrophysics Data System (ADS)

    Eskin, Gregory

    2014-12-01

    We study the existence of analogue nonstationary spherically symmetric black holes. The prime example is the acoustic model see Unruh (1981 Phys. Rev. Lett. 46 1351). We consider also a more general class of metrics that could be useful in other physical models of analogue black and white holes. We give examples of the appearance of black holes and of disappearance of white holes. We also discuss the relation between the apparent and the event horizons for the case of analogue black holes. In the end we study the inverse problem of determination of black or white holes by boundary measurements for the spherically symmetric nonstationary metrics.

  12. Risk Prediction for Progression of Macular Degeneration: 10 Common and Rare Genetic Variants, Demographic, Environmental, and Macular Covariates

    PubMed Central

    Seddon, Johanna M.; Silver, Rachel E.; Kwong, Manlik; Rosner, Bernard

    2015-01-01

    Purpose. To determine the association between genetic variants and transition to advanced age-related macular degeneration (AMD), and to develop a predictive model and online application to assist in clinical decision making. Methods. Among 2951 subjects in the Age-Related Eye Disease Study, 834 progressed from no AMD, early AMD, or intermediate AMD to advanced disease. Survival analysis was used to assess which genetic, demographic, environmental, and macular covariates were independently associated with progression. Attributable risk, area under the curve statistics (AUCs), and reclassification odds ratios (ORs) were calculated. Split-sample validation was performed. An online risk calculator was developed and is available in the public domain at www.seddonamdriskscore.org. Results. Ten genetic loci were independently associated with progression, including newly identified rare variant C3 K155Q (hazard ratio: 1.7, 95% confidence interval: 1.2–2.5, P = 0.002), three variants in CFH, and six variants in ARMS2/HTRA1, CFB, C3, C2, COL8A1, and RAD51B. Attributable risk calculations revealed that 80% of incident AMD is attributable to genetic factors, adjusting for demographic covariates and baseline macular phenotypes. In a model including 10 genetic loci, age, sex, education, body mass index, smoking, and baseline AMD status, the AUC for progression to advanced AMD over 10 years was 0.911. Split-sample validation showed a similar AUC (0.907). Reclassification analyses indicated that subjects were categorized into a more accurate risk category if genetic information was included (OR 3.2, P < 0.0001). Conclusions. Rare variant C3 K155Q was independently associated with AMD progression. The comprehensive model may be useful for identifying and monitoring high-risk patients, selecting appropriate therapies, and designing clinical trials. PMID:25655794

  13. Macular Function in Macular Degenerations: Repeatability of Microperimetry as a Potential Outcome Measure for ABCA4-Associated Retinopathy Trials

    PubMed Central

    Swider, Malgorzata; Aleman, Tomas S.; Feuer, Willam J.; Schwartz, Sharon B.; Russell, Robert C.; Steinberg, Janet D.; Stone, Edwin M.; Jacobson, Samuel G.

    2012-01-01

    Purpose. To measure macular visual function in patients with unstable fixation, to define the photoreceptor source of this function, and to estimate its test-retest repeatability as a prerequisite to clinical trials. Methods. Patients (n = 38) with ABCA4-associated retinal degeneration (RD) or with retinitis pigmentosa (RP) were studied with retina-tracking microperimetry along the foveo-papillary profile between the fovea and the optic nerve head, and point-by-point test-retest repeatability was estimated. A subset with foveal fixation was also studied with dark-adapted projection perimetry using monochromatic blue and red stimuli along the horizontal meridian. Results. Macular function in ABCA4-RD patients transitioned from lower sensitivity at the parafovea to higher sensitivity in the perifovea. RP patients had the inverse pattern. Red-on-red microperimetric sensitivities successfully avoided ceiling effects and were highly correlated with absolute sensitivities. Point-by-point test-retest limits (95% confidence intervals) were ±4.2 dB; repeatability was not related to mean sensitivity, eccentricity from the fovea, age, fixation location, or instability. Repeatability was also not related to the local slope of sensitivity and was unchanged in the parapapillary retina. Conclusions. Microperimetry allows reliable testing of macular function in RD patients without foveal fixation in longitudinal studies evaluating natural disease progression or efficacy of therapeutic trials. A single estimate of test-retest repeatability can be used to determine significant changes in visual function at individual retinal loci within diseased regions that are homogeneous and those that are heterogeneous and also in transition zones at high risk for disease progression. PMID:22247458

  14. Assessment of reading behavior with an infrared eye tracker after 360° macular translocation for age-related macular degeneration.

    PubMed

    Uppal, Gurmit; Feely, Mary P; Crossland, Michael D; Membrey, Luke; Lee, John; da Cruz, Lyndon; Rubin, Gary S

    2011-08-01

    PURPOSE. Macular translocation (MT360) is complex surgery used to restore reading in exudative age-related macular degeneration (AMD). MT360 involves retinal rotation and subsequent oculomotor globe counterrotation and is not without significant surgical risk. This study attempts to gauge the optimal potential of MT360 in restoring reading ability and describe the quality and extent of recovery. METHODS. The six best outcomes were examined from a consecutive series of 23 MT360 cases. Reading behavior and fixation characteristics were examined with an infrared eye tracker. Results were compared to age-matched normal subjects and patients with untreated exudative and nonexudative AMD. Retinal sensitivity was examined with microperimetry to establish threshold visual function. RESULTS. MT360 produced significant improvements in visual function over untreated disease and approximated normal function for reading speed and fixation quality. Relative to the comparative groups, eye tracking revealed the MT360 cohort generated a greater number of horizontal and vertical saccades, of longer latency and reduced velocity. In contrast, saccadic behavior when reading (forward and regressive saccades) closely matched normal function. Microperimetry revealed a reduction in the central scotoma with three patients recovering normal foveal sensitivity. CONCLUSIONS. Near normal reading function is recovered despite profound surgical disruption to the anatomy (retinal/oculomotor). MT360 restores foveal function sufficient to produce a single stable locus of fixation, with marked reduction of the central scotoma. Despite the limitations on saccadic function, the quality of reading saccadic behavior is maintained with good reading ability. Oculomotor surgery appears not to limit reading ability, and the results of retinal surgery approximate normal macular function. PMID:21596822

  15. Present and future treatment possibilities in macular degeneration

    NASA Astrophysics Data System (ADS)

    Fisher, E.; Wegner, A.; Pfeiler, T.; Mertz, M.

    2005-11-01

    Purpose: To discuss present and future treatment possibilities in different types of choroidal neovascularisation. Methods: Presented are angiographic- and OCT-findings in patients with macular degeneration of different origin. Choroidal neovascularisations, which are not likely to respond positively to established procedures like thermal laser coagulation or photodynamic therapy will be discussed. Results and conclusions: Present study-guidelines and new methods of pharmacological intervention are analysed in different patterns of macular degeneration. Conventional laser coagulation in the treatment of classic, extrafoveal CNV and photodynamic therapy of predominantly classic subfoveal CNV still represent a gold standard. There are new recommendations, loosening the tight criteria of the TAP and VIP-guidelines, which cover, for instance, wider visual acuity ranges and the treatment of juxtafoveally located choroidal neovascularisations. Positive findings in literature confirm the role of PDT in pathologic myopia and other non-AMD CNV. Studies about surgical procedures, like macula- or RPE-translocation after surgical removal or thermal laser destruction of the CNV are in progress and are expected to show promising results. Phase II/III studies will soon point out the effect of anti-VEGF agents. The application of intravitreal (triamcinolone) or peribulbar (anecortave acetat) steroids could be useful. The combination with surgical or laser techniques could bring further benefit to the patient.

  16. Historic perspectives. Macular yellow pigment. The first 200 years.

    PubMed

    Nussbaum, J J; Pruett, R C; Delori, F C

    1981-01-01

    Since 1782 there has been continuing controversy concerning the curious central coloration referred to as "macular yellow," but no cumulative source of information on the subject exists. This paper reviews the research efforts of two centuries to determine the existence, nature, location, and function of a specialized pigment in the foveal region. Using white-light illumination, it is difficult to see a macular yellow spot in the living eye; it is best observed and documented by red-free ophthalmoscopy and blue-light monochromatic photography. Histologic, biochemical, and spectral absorption data suggest that the yellow color is due to a xanthophyllic pigment, lutein, that is distributed in all retinal layers internal to the outer nuclear layer, with greatest concentration in the outer and inner plexiform layers. Clinically absent in newborns, the pigment gradually accumulates from dietary sources and appears to serve both as an optical filter, by absorbing blue light and reducing chromatic aberration, and in a protective capacity, preventing actinic damage. The absorption characteristics of the yellow pigment contribute to the central dark spot seen during fluorescein angiography and to the risk of photocoagulation near the fovea. Its apparent absence in albinos and the reported functional improvement in certain degenerative retinopathies following supplemental xanthophyll administration suggest a possible role in hereditary or acquired maculopathies. PMID:6758089

  17. [Retinal vein occlusion management algorithm. Part 2. Macular edema].

    PubMed

    Budzinskaya, M V; Mazurina, N K; Egorov, A E; Kuroedov, A V; Loskutov, I A; Plyukhova, A A; Razik, S; Ryabtseva, A A; Simonova, S V

    2015-01-01

    Macular edema (ME) is the most common complication of both ischemic and nonischemic retinal vein occlusion (RVO). If the main trunk of the central retinal vein is involved, ME occurs in 100% of cases. According to the Central Vein Occlusion Study, in 65% of RVO and ME patients with baseline visual acuity (VA) of at least 0.5 (Golovin-Sivtsev chart) or higher, ME may resolve itself without treatment with subsequent VA improvement. Therefore, we recommend a 3-month treatment-free follow-up of nonischemic central RVO (CRVO) and ME patients with VA of 0.5 or higher. If no improvement is noted within this period, treatment is initiated. Immediate treatment is required in patients with cystic ME revealed by optical coherence tomography (OCT) and VA below 0.5. Ischemic maculopathy is extremely unpromising. Modified grid laser photocoagulation should not be used as monotherapy for macular edema. Repeated corticosteroid (Ozurdex) and/or anti-VEGF (ranibizumab, aflibercept) intravitreal injections are considered the first choice treatment for ME in CRVO patients. Efficiency assessments should include monthly OCT. For persistent ME, intravitreal therapy can be supplemented by laser retinal photocoagulation (panretinal or modified grid). Anti-VEGF treatment schemes should be adjusted in BRVO patients as most of their edemas are self-limiting. Of laser photocoagulation techniques, only modified grid is used. PMID:26977728

  18. Historic perspectives. Macular yellow pigment. The first 200 years.

    PubMed

    Nussbaum, J J; Pruett, R C; Delori, F C

    1981-01-01

    Since 1782 there has been continuing controversy concerning the curious central coloration referred to as "macular yellow," but no cumulative source of information on the subject exists. This paper reviews the research efforts of two centuries to determine the existence, nature, location, and function of a specialized pigment in the foveal region. Using white-light illumination, it is difficult to see a macular yellow spot in the living eye; it is best observed and documented by red-free ophthalmoscopy and blue-light monochromatic photography. Histologic, biochemical, and spectral absorption data suggest that the yellow color is due to a xanthophyllic pigment, lutein, that is distributed in all retinal layers internal to the outer nuclear layer, with greatest concentration in the outer and inner plexiform layers. Clinically absent in newborns, the pigment gradually accumulates from dietary sources and appears to serve both as an optical filter, by absorbing blue light and reducing chromatic aberration, and in a protective capacity, preventing actinic damage. The absorption characteristics of the yellow pigment contribute to the central dark spot seen during fluorescein angiography and to the risk of photocoagulation near the fovea. Its apparent absence in albinos and the reported functional improvement in certain degenerative retinopathies following supplemental xanthophyll administration suggest a possible role in hereditary or acquired maculopathies.

  19. Asymmetric Macular Structural Damage Is Associated With Relative Afferent Pupillary Defects in Patients With Glaucoma

    PubMed Central

    Gracitelli, Carolina P. B.; Tatham, Andrew J.; Zangwill, Linda M.; Weinreb, Robert N.; Abe, Ricardo Y.; Diniz-Filho, Alberto; Paranhos, Augusto; Baig, Saif; Medeiros, Felipe A.

    2016-01-01

    Purpose We examined the relationship between relative afferent pupillary defects (RAPDs) and macular structural damage measured by macular thickness and macular ganglion cell-inner plexiform layer (mGCIPL) thickness in patients with glaucoma. Methods A cross-sectional study was done of 106 glaucoma patients and 85 healthy individuals from the Diagnostic Innovations in Glaucoma Study. All subjects underwent standard automated perimetry (SAP) and optic nerve and macular imaging using Cirrus Spectral Domain Optical Coherence Tomography (SDOCT). Glaucoma was defined as repeatable abnormal SAP or progressive glaucomatous changes on stereo photographs. Pupil responses were assessed using an automated pupillometer, which records the magnitude of RAPD (RAPD score), with additional RAPD scores recorded for each of a series of colored stimuli (blue, red, green, and yellow). The relationship between RAPD score and intereye differences (right minus left eye) in circumpapillary retinal nerve fiber layer (cpRNFL) thickness, mGCIPL, macular thickness, and SAP mean deviation (MD), was examined using linear regression. Results There was fair correlation between RAPD score and asymmetric macular structural damage measured by intereye difference in mGCIPL thickness (R2 = 0.285, P < 0.001). The relationship between RAPD score and intereye difference in macular thickness was weaker (R2 = 0.167, P < 0.001). Intereye difference in cpRNFL thickness (R2 = 0.350, P < 0.001) and SAP MD (R2 = 0.594, P < 0.001) had stronger association with RAPD scores compared to intereye difference in mGCIPL and macular thickness. Conclusions Objective assessment of pupillary responses using a pupillometer was associated with asymmetric macular structural damage in patients with glaucoma. PMID:27064394

  20. NASA Now: Black Holes

    NASA Video Gallery

    In this NASA Now episode, Dr. Daniel Patnaude talks about how his team discovered a baby black hole, why this is important and how black holes create tidal forces. Throughout his discussion, Patnau...

  1. Black holes without firewalls

    NASA Astrophysics Data System (ADS)

    Larjo, Klaus; Lowe, David A.; Thorlacius, Larus

    2013-05-01

    The postulates of black hole complementarity do not imply a firewall for infalling observers at a black hole horizon. The dynamics of the stretched horizon, that scrambles and reemits information, determines whether infalling observers experience anything out of the ordinary when entering a large black hole. In particular, there is no firewall if the stretched horizon degrees of freedom retain information for a time of the order of the black hole scrambling time.

  2. A layered approach to raising public awareness of macular degeneration in Australia.

    PubMed

    Heraghty, Julie; Cummins, Robert

    2012-09-01

    Between 2007 and 2011, the Australian Macular Degeneration Foundation conducted a multifaceted campaign to increase public awareness of macular degeneration. Regular national polls conducted by an independent social research company have shown that awareness of macular degeneration increased from 47% to 80% in Australians aged 16 years or older and from 58% to 92% in those aged 50 years or older. The percentage of people aged 50 years or older who reported having had their macula checked in the 2 years prior to the survey increased from 33% to 70% from 2007 to 2011. Other measures, including analysis of Medicare data, have confirmed the success of the campaign.

  3. A Layered Approach to Raising Public Awareness of Macular Degeneration in Australia

    PubMed Central

    Heraghty, Julie; Cummins, Robert

    2012-01-01

    Between 2007 and 2011, the Australian Macular Degeneration Foundation conducted a multifaceted campaign to increase public awareness of macular degeneration. Regular national polls conducted by an independent social research company have shown that awareness of macular degeneration increased from 47% to 80% in Australians aged 16 years or older and from 58% to 92% in those aged 50 years or older. The percentage of people aged 50 years or older who reported having had their macula checked in the 2 years prior to the survey increased from 33% to 70% from 2007 to 2011. Other measures, including analysis of Medicare data, have confirmed the success of the campaign. PMID:22813341

  4. The Nearest Black Hole

    NASA Technical Reports Server (NTRS)

    Oliversen, Ronald (Technical Monitor); Garcia, Michael

    2005-01-01

    The goal of this program is to study black holes, both in our Galaxy and in nearby galaxies. We aim to study both 'stellar mass' x-ray binaries containing black holes (both in our Galaxy and in nearby galaxies), and super-massive black holes in nearby galaxies.

  5. Analysing the Progression Rates of Macular Lesions with Autofluorescence Imaging Modes in Dry Age-Related Macular Degeneration

    PubMed Central

    Olcay, Kenan; Çakır, Akın; Sönmez, Murat; Düzgün, Eyüp; Yıldırım, Yıldıray

    2015-01-01

    Objectives: In this study we aimed to compare the sensitivity of blue-light fundus autofluorescence (FAF) and near-infrared autofluorescence (NI-AF) imaging for determining the progression rates of macular lesions in dry age-related macular degeneration (AMD). Materials and Methods: The study was designed retrospectively and included patients diagnosed with intermediate and advanced stage dry AMD. Best corrected visual acuities and FAF and NI-AF images were recorded in 46 eyes of 33 patients. Lesion borders were drawn manually on the images using Heidelberg Eye Explorer software and lesion areas were calculated using Microsoft Excel software. BCVA and lesion areas were compared with each other. Results: Patients’ mean follow-up time was 30.98±13.30 months. The lesion area progression rates were 0.85±0.93 mm2/y in FAF and 0.93±1.01 mm2/y in NI-AF, showing statistically significant correlation with each other (r=0.883; p<0.01). Both imaging methods are moderately correlated with visual acuity impairment (r=0.362; p<0.05 and r=0.311; p<0.05, respectively). In addition, larger lesions showed higher progression rates than smaller ones in both imaging methods. Conclusion: NI-AF imaging is as important and effective as FAF imaging for follow-up of dry AMD patients. PMID:27800240

  6. Black Hole Battery

    NASA Astrophysics Data System (ADS)

    Levin, Janna; D'Orazio, Daniel

    2016-03-01

    Black holes are dark dead stars. Neutron stars are giant magnets. As the neutron star orbits the black hole, an electronic circuit forms that generates a blast of power just before the black hole absorbs the neutron star whole. The black hole battery conceivably would be observable at cosmological distances. Possible channels for luminosity include synchro-curvature radiation, a blazing fireball, or even an unstable, short-lived black hole pulsar. As suggested by Mingarelli, Levin, and Lazio, some fraction of the battery power could also be reprocessed into coherent radio emission to populate a subclass of fast radio bursts.

  7. Searching for Black Holes

    NASA Technical Reports Server (NTRS)

    Garica, M.

    2001-01-01

    In 1995 we proposed to carry out ground-based observations in order to securely identify stellar mass black holes in our galaxy. This type 4 proposal under NASA's UV, Visible, and Gravitational Astrophysics program compliments NASA's space-based research by following up black hole candidates found and studied with space-based observatories, in order to determine if they are indeed black holes. While our primary goal is to securely identify black holes by measuring their masses, a secondary goal is identifying unique visible-range signatures for black holes.

  8. Black hole accretion.

    PubMed

    Narayan, Ramesh; Quataert, Eliot

    2005-01-01

    Black holes are most often detected by the radiation produced when they gravitationally pull in surrounding gas, in a process called accretion. The efficiency with which the hot gas radiates its thermal energy strongly influences the geometry and dynamics of the accretion flow. Both radiatively efficient thin disks and radiatively inefficient thick disks are observed. When the accreting gas gets close to the central black hole, the radiation it produces becomes sensitive to the spin of the hole and the presence of an event horizon. Analysis of the luminosities and spectra of accreting black holes has yielded tantalizing evidence for both rotating holes and event horizons. Numerical simulations imply that the relativistic jets often seen from accreting black holes may be powered in part by the spin of the hole. PMID:15637269

  9. New Treatment Greatly Improves Prognosis for Patients with AMD (Age-Related Macular Degeneration)

    MedlinePlus

    ... turn JavaScript on. Feature: Age-related Macular Degeneration New Treatment Greatly Improves Prognosis for Patients with AMD ... Eye Institute Photo Courtesy of: NEI In a new study of nearly 650 people with age-related ...

  10. Comparison of macular versus paramacular retinal sensitivity to femtosecond laser pulses

    NASA Astrophysics Data System (ADS)

    Cain, Clarence P.; Toth, Cynthia A.; Thomas, Robert J.; Noojin, Gary D.; Carothers, Val; Stolarski, David J.; Rockwell, Benjamin A.

    2000-07-01

    Single 130 fs laser pulses in the near-IR (800 nm) were used to create ophthalmoscopically viewed minimum visible lesions (MVLs) within the macular and paramacular regions in rhesus monkey eyes. MVL thresholds at 1 and 24 h are reported as the 50% probability for damage (ED50) together with their fiducial limits at the 95% confidence level. These measured thresholds are compared with previously reported thresholds for near-IR and visible wavelengths for both macular and paramacular areas. Threshold doses were lower at the 24 h reading than at the 1 h reading for both retinal regions and the ED50s for the macular were slightly lower than for the paramacula. We measured the 24 h MVL ED50 thresholds to be 0.35 and 0.55 (mu) J for the macular and paramacular areas, respectively. The combined data for both areas yielded a threshold of 0.45 (mu) J.

  11. Etiology and treatment of the inflammatory causes of cystoid macular edema.

    PubMed

    Cho, Hyung; Madu, Assumpta

    2009-01-01

    Cystoid macular edema in its various forms can be considered one of the leading causes of central vision loss in the developed world. It occurs in a wide variety of pathologic conditions and represents the final common pathway of several basic processes. Therapeutic approaches to cystoid macular edema depend on a clear understanding of its contributing pathophysiologic mechanisms. This review will discuss the mechanism of ocular inflammation in cystoid macular edema with a particular focus on the inflammatory causes: post-operative, uveitic, and after laser procedures. A variety of pharmacologic agents targeting inflammatory molecules have been shown to reduce macular edema and improve visual function. However, the long-term efficacy and safety of most new therapies have yet to be established in controlled clinical trials.

  12. Etiology and treatment of the inflammatory causes of cystoid macular edema

    PubMed Central

    Cho, Hyung; Madu, Assumpta

    2009-01-01

    Cystoid macular edema in its various forms can be considered one of the leading causes of central vision loss in the developed world. It occurs in a wide variety of pathologic conditions and represents the final common pathway of several basic processes. Therapeutic approaches to cystoid macular edema depend on a clear understanding of its contributing pathophysiologic mechanisms. This review will discuss the mechanism of ocular inflammation in cystoid macular edema with a particular focus on the inflammatory causes: post-operative, uveitic, and after laser procedures. A variety of pharmacologic agents targeting inflammatory molecules have been shown to reduce macular edema and improve visual function. However, the long-term efficacy and safety of most new therapies have yet to be established in controlled clinical trials. PMID:22096351

  13. Macular pigment and the edge hypothesis of flicker photometry.

    PubMed

    Bone, Richard A; Landrum, John T; Gibert, Jorge C

    2004-12-01

    Heterochromatic flicker photometry is commonly used to measure macular pigment optical density (MPOD) in the human retina. It has been proposed, and accepted by many, that the MPOD so measured represents the value at a retinal location corresponding to the edge of the flickering, circular stimulus. We have investigated this proposal by using a series of annular stimuli to determine the MPOD distribution in the central 1.5 degrees of the retina for both eyes of 10 subjects. The MPOD obtained using a 1.5 degrees circular stimulus matched the MPOD distribution at a retinal eccentricity that was always less than the stimulus radius, and averaged, for the 10 subjects, 51% of the stimulus radius. Similar results were obtained using a 1 degrees stimulus. Thus the edge hypothesis is inconsistent with our data. We suggest that involuntary eye movements may be responsible for an apparent edge effect.

  14. Gene-Diet Interactions in Age-Related Macular Degeneration.

    PubMed

    Rowan, Sheldon; Taylor, Allen

    2016-01-01

    Age-related macular degeneration (AMD) is a prevalent blinding disease, accounting for roughly 50 % of blindness in developed nations. Very significant advances have been made in terms of discovering genetic susceptibilities to AMD as well as dietary risk factors. To date, nutritional supplementation is the only available treatment option for the dry form of the disease known to slow progression of AMD. Despite an excellent understanding of genes and nutrition in AMD, there is remarkably little known about gene-diet interactions that may identify efficacious approaches to treat individuals. This review will summarize our current understanding of gene-diet interactions in AMD with a focus on animal models and human epidemiological studies.

  15. A Revised Hemodynamic Theory of Age-Related Macular Degeneration.

    PubMed

    Gelfand, Bradley D; Ambati, Jayakrishna

    2016-08-01

    Age-related macular degeneration (AMD) afflicts one out of every 40 individuals worldwide, causing irreversible central blindness in millions. The transformation of various tissue layers within the macula in the retina has led to competing conceptual models of the molecular pathways, cell types, and tissues responsible for the onset and progression of AMD. A model that has persisted for over 6 decades is the hemodynamic, or vascular theory of AMD progression, which states that vascular dysfunction of the choroid underlies AMD pathogenesis. Here, we re-evaluate this hypothesis in light of recent advances on molecular, anatomic, and hemodynamic changes underlying choroidal dysfunction in AMD. We propose an updated, detailed model of hemodynamic dysfunction as a mechanism of AMD development and progression. PMID:27423265

  16. Molecular pathology of age-related macular degeneration

    PubMed Central

    Ding, Xiaoyan; Patel, Mrinali; Chan, Chi-Chao

    2009-01-01

    Age-related macular degeneration (AMD) is a leading cause of irreversible blindness in the world. Although the etiology and pathogenesis of AMD remain largely unclear, a complex interaction of genetic and environmental factors is thought to exist. AMD pathology is characterized by degeneration involving the retinal photoreceptors, retinal pigment epithelium, and Bruch’s membrane, as well as, in some cases, alterations in choroidal capillaries. Recent research on the genetic and molecular underpinnings of AMD brings to light several basic molecular pathways and pathophysiological processes that might mediate AMD risk, progression, and/or response to therapy. This review summarizes, in detail, the molecular pathological findings in both humans and animal models, including genetic variations in CFH, CX3CR1, and ARMS2/HtrA1, as well as the role of numerous molecules implicated in inflammation, apoptosis, cholesterol trafficking, angiogenesis, and oxidative stress. PMID:19026761

  17. Radiation Therapy for Neovascular Age-related Macular Degeneration

    SciTech Connect

    Kishan, Amar U.; Modjtahedi, Bobeck S.; Morse, Lawrence S.; Lee, Percy

    2013-03-01

    In the enormity of the public health burden imposed by age-related macular degeneration (ARMD), much effort has been directed toward identifying effective and efficient treatments. Currently, anti-vascular endothelial growth factor (VEGF) injections have demonstrated considerably efficacy in treating neovascular ARMD, but patients require frequent treatment to fully benefit. Here, we review the rationale and evidence for radiation therapy of ARMD. The results of early photon external beam radiation therapy are included to provide a framework for the sequential discussion of evidence for the usage of stereotactic radiation therapy, proton therapy, and brachytherapy. The evidence suggests that these 3 modern modalities can provide a dose-dependent benefit in the treatment of ARMD. Most importantly, preliminary data suggest that all 3 can be used in conjunction with anti-VEGF therapeutics, thereby reducing the frequency of anti-VEGF injections required to maintain visual acuity.

  18. Targeting MAPK Signaling in Age-Related Macular Degeneration

    PubMed Central

    Kyosseva, Svetlana V.

    2016-01-01

    Age-related macular degeneration (AMD) is a major cause of irreversible blindness affecting elderly people in the world. AMD is a complex multifactorial disease associated with demographic, genetics, and environmental risk factors. It is well established that oxidative stress, inflammation, and apoptosis play critical roles in the pathogenesis of AMD. The mitogen-activated protein kinase (MAPK) signaling pathways are activated by diverse extracellular stimuli, including growth factors, mitogens, hormones, cytokines, and different cellular stressors such as oxidative stress. They regulate cell proliferation, differentiation, survival, and apoptosis. This review addresses the novel findings from human and animal studies on the relationship of MAPK signaling with AMD. The use of specific MAPK inhibitors may represent a potential therapeutic target for the treatment of this debilitating eye disease. PMID:27385915

  19. Complement factor H polymorphism and age-related macular degeneration.

    PubMed

    Edwards, Albert O; Ritter, Robert; Abel, Kenneth J; Manning, Alisa; Panhuysen, Carolien; Farrer, Lindsay A

    2005-04-15

    Age-related macular degeneration (AMD) is a common, late-onset, and complex trait with multiple risk factors. Concentrating on a region harboring a locus for AMD on 1q25-31, the ARMD1 locus, we tested single-nucleotide polymorphisms for association with AMD in two independent case-control populations. Significant association (P = 4.95 x 10(-10)) was identified within the regulation of complement activation locus and was centered over a tyrosine-402 --> histidine-402 protein polymorphism in the gene encoding complement factor H. Possession of at least one histidine at amino acid position 402 increased the risk of AMD 2.7-fold and may account for 50% of the attributable risk of AMD.

  20. Age-related macular degeneration and the complement system.

    PubMed

    Khandhadia, S; Cipriani, V; Yates, J R W; Lotery, A J

    2012-02-01

    Age-related macular degeneration (AMD) is the leading cause of blindness in the developed world. It is a complex multifactorial disease, and despite new advances in treatment, many patients still succumb to visual impairment. The complement pathway has been implicated in the pathogenesis of many diseases, and recently variants in several genes encoding complement pathway proteins have been associated with AMD. Complement proteins have been found in histological specimens of eyes with AMD. Altered levels of both intrinsic complement proteins and activated products have been found in the circulation of patients with AMD. Complement activation may be triggered by oxidative stress, resulting from retinal exposure to incoming light; indeed an inter-play between these two pathological processes seems to exist. Finally, complement inhibitors are currently being evaluated in clinical trials. This article reviews the role of the complement system in AMD, and the potential of complement inhibition in preventing the devastating blindness resulting from this disease.

  1. Aflibercept for the treatment of diabetic macular edema.

    PubMed

    Harkins, Keegan A; Haschke, Mary; Do, Diana V

    2016-05-01

    Diabetic macular edema (DME) is an accumulation of fluid in the central retina, secondary to vascular-leakage from diabetic vascular damage. DME and other ophthalmic sequela of diabetes are the leading cause of blindness in 20 to 74-year-olds. The development of VEGF-inhibitors (anti-VEGF) has revolutionized DME treatment improving the clinician's ability to remove excess fluid from the macula, improving visual-acuity. Aflibercept is an anti-VEGF agent made of a recombinant fusion protein (consisting of VEGF receptors 1 and 2 extracellular domains) fused with the Fc-portion of human-IgG1, which binds both VEGF isoforms A and B, and placental growth factor. Phase III clinical trials and published scientific studies have demonstrated the efficacy of intravitreal aflibercept injection in the treatment of DME. PMID:26907516

  2. Mediated-reality magnification for macular degeneration rehabilitation

    NASA Astrophysics Data System (ADS)

    Martin-Gonzalez, Anabel; Kotliar, Konstantin; Rios-Martinez, Jorge; Lanzl, Ines; Navab, Nassir

    2014-10-01

    Age-related macular degeneration (AMD) is a gradually progressive eye condition, which is one of the leading causes of blindness and low vision in the Western world. Prevailing optical visual aids compensate part of the lost visual function, but omitting helpful complementary information. This paper proposes an efficient magnification technique, which can be implemented on a head-mounted display, for improving vision of patients with AMD, by preserving global information of the scene. Performance of the magnification approach is evaluated by simulating central vision loss in normally sighted subjects. Visual perception was measured as a function of text reading speed and map route following speed. Statistical analysis of experimental results suggests that our magnification method improves reading speed 1.2 times and spatial orientation to find routes on a map 1.5 times compared to a conventional magnification approach, being capable to enhance peripheral vision of AMD subjects along with their life quality.

  3. Macular pigment density measured by autofluorescence spectrometry: comparison with reflectometry and heterochromatic flicker photometry.

    PubMed

    Delori, F C; Goger, D G; Hammond, B R; Snodderly, D M; Burns, S A

    2001-06-01

    We present a technique for estimating the density of the human macular pigment noninvasively that takes advantage of the autofluorescence of lipofuscin, which is normally present in the human retinal pigment epithelium. By measuring the intensity of fluorescence at 710 nm, where macular pigment has essentially zero absorption, and stimulating the fluorescence with two wavelengths, one well absorbed by macular pigment and the other minimally absorbed by macular pigment, we can make accurate single-pass measurements of the macular pigment density. We used the technique to measure macular pigment density in a group of 159 subjects with normal retinal status ranging in age between 15 and 80 years. Average macular pigment density was 0.48 +/- 0.16 density unit (D.U.) for a 2 degrees -diameter test field. We show that these estimates are highly correlated with reflectometric (mean: 0.23 +/- 0.07 D.U.) and psychophysical (mean: 0.37 +/- 0.26 D.U.; obtained by heterochromatic flicker photometry) estimates of macular pigment in the same subjects, despite the fact that systematic differences in the estimated density exist between techniques. Repeat measurements over both short- and long-time intervals indicate that the autofluorescence technique is reproducible: The mean absolute difference between estimates was less than 0.05 D.U., superior to the reproducibility obtained by reflectometry and flicker photometry. To understand the systematic differences between density estimates obtained from the different methods, we analyzed the underlying assumptions of each technique. Specifically, we looked at the effect of self-screening by visual pigment, the effect of changes in optical property of the deeper retinal layers, including the role of retinal pigmented epithelium melanin, and the role of secondary fluorophores and reflectors in the anterior layers of the retina.

  4. Association of Diabetic Macular Nonperfusion With Outer Retinal Disruption on Optical Coherence Tomography

    PubMed Central

    Scarinci, Fabio; Jampol, Lee M.; Linsenmeier, Robert A.; Fawzi, Amani A.

    2015-01-01

    IMPORTANCE Diabetic macular nonperfusion leads to decreased perifoveal capillary blood flow, which in turn causes chronic ischemia of the retinal tissue. Using point-to-point correlation between spectral-domain optical coherence tomography (SD-OCT) and nonperfusion on fluorescein angiography, we observed that retinal capillary nonperfusion is associated with photoreceptor compromise on OCT. This study highlights a new concept of a possible contribution of the retinal deep capillary plexus to photoreceptor compromise in diabetic retinopathy in the absence of diabetic macular edema. OBJECTIVE To report outer retinal structural changes associated with enlargement of the foveal avascular zone and/or capillary nonperfusion in the macular area of diabetic patients. DESIGN, SETTING, AND PARTICIPANTS Retrospective observational cross-sectional study in 9 patients who were diagnosed as having diabetic retinopathy without diabetic macular edema and underwent fluorescein angiography and SD-OCT for diabetic retinopathy from July 8, 2014, to December 1, 2014, at a tertiary academic referral center. This analysis was conducted between December 2, 2014, and January 31, 2015. MAIN OUTCOMES AND MEASURES Outer retinal changes on SD-OCT in areas of macular ischemia. RESULTS The study included 13 eyes of 9 diabetic patients (4 men and 5 women aged 34–58 years) with a mean duration of diabetes mellitus of 14.5 years. Nine eyes showed outer retinal disruption revealed by SD-OCT that colocalized to areas of enlargement of the foveal avascular zone and macular capillary nonperfusion. Four fellow eyes with normal foveal avascular zones did not show any retinal changes on SD-OCT. CONCLUSIONS AND RELEVANCE Macular ischemia in diabetic patients can be associated with photoreceptor compromise. The presence of disruption of the photoreceptors on OCT in diabetic patients can be a manifestation of underlying capillary nonperfusion in eyes without diabetic macular edema. Ischemia at the deep

  5. Age-related macular degeneration: Evidence of a major gene

    SciTech Connect

    Bhatt, S.; Warren, C.; Yang, H.

    1994-09-01

    Age-related macular degeneration is a major cause of blindness in developing countries. It remains a very poorly understood disorder. Although environmental and genetic factors have been implicated in its pathogenesis, none have been firmly implicated. The purpose of this study was to use pedigree analysis to evaluate the possible role of a major gene as a determinant of familial aggregation. Information was collected regarding occupation, smoking, sun exposure, associated medical problems and family history. 50 probands with age-related macular degeneration (ARMD) and 39 age, race and sex-matched controls were included in the study. In the ARMD group 15/50 (30%) of probands reported a positive family history; 22 out of 222 first degree relatives over age 60 were reported to be affected. In the control groups, none of the 138 first degree relatives over age 50 had a history of ARMD. This difference is statistically significant (p = 0.0003), indicating that genetic factors may play an important role in the pathogenesis of ARMD. In the ARMD group more siblings as compared to parents (16/127 vs. 5/82) were affected. 5/50 (10%) of the ARMD probands also gave a history of a second degree relative affected with ARMD, compared to none known among the relatives of controls. Data from 50 pedigrees were analyzed by complex segregation analysis under a class A regressive logistic model using the REGD program implemented in the SAGE package. Preliminary results allow rejection of a polygenic model and suggest there is a major gene for ARMD in these families. The inheritance model most compatible with the observed familial aggregation is autosomal recessive. In conclusion, these results are suggestive of a major gene effect in the etiology of ARMD. Identification of a major gene effect is a first step to further pursue linkage analysis and to search for the gene(s) involved in the causation of ARMD.

  6. Analysis of candidate genes for macular telangiectasia type 2

    PubMed Central

    Parmalee, Nancy L.; Schubert, Carl; Merriam, Joanna E.; Allikmets, Kaija; Bird, Alan C.; Gillies, Mark C.; Peto, Tunde; Figueroa, Maria; Friedlander, Martin; Fruttiger, Marcus; Greenwood, John; Moss, Stephen E.; Smith, Lois E.H.; Toomes, Carmel; Inglehearn, Chris F.

    2010-01-01

    Purpose To find the gene(s) responsible for macular telangiectasia type 2 (MacTel) by a candidate-gene screening approach. Methods Candidate genes were selected based on the following criteria: those known to cause or be associated with diseases with phenotypes similar to MacTel, genes with known function in the retinal vasculature or macular pigment transport, genes that emerged from expression microarray data from mouse models designed to mimic MacTel phenotype characteristics, and genes expressed in the retina that are also related to diabetes or hypertension, which have increased prevalence in MacTel patients. Probands from eight families with at least two affected individuals were screened by direct sequencing of 27 candidate genes. Identified nonsynonymous variants were analyzed to determine whether they co-segregate with the disease in families. Allele frequencies were determined by TaqMan analysis of the large MacTel and control cohorts. Results We identified 23 nonsynonymous variants in 27 candidate genes in at least one proband. Of these, eight were known single nucleotide polymorphisms (SNPs) with allele frequencies of >0.05; these variants were excluded from further analyses. Three previously unidentified missense variants, three missense variants with reported disease association, and five rare variants were analyzed for segregation and/or allele frequencies. No variant fulfilled the criteria of being causal for MacTel. A missense mutation, p.Pro33Ser in frizzled homolog (Drosophila) 4 (FZD4), previously suggested as a disease-causing variant in familial exudative vitreoretinopathy, was determined to be a rare benign polymorphism. Conclusions We have ruled out the exons and flanking intronic regions in 27 candidate genes as harboring causal mutations for MacTel. PMID:21179236

  7. Interactive retinal blood flow analysis of the macular region.

    PubMed

    Tian, Jing; Somfai, Gábor Márk; Campagnoli, Thalmon R; Smiddy, William E; Debuc, Delia Cabrera

    2016-03-01

    The study of retinal hemodynamics plays an important role to understand the onset and progression of diabetic retinopathy. In this work, we developed an interactive retinal analysis tool to quantitatively measure the blood flow velocity (BFV) and blood flow rate (BFR) in the macular region using the Retinal Function Imager (RFI). By employing a high definition stroboscopic fundus camera, the RFI device is able to assess retinal blood flow characteristics in vivo. However, the measurements of BFV using a user-guided vessel segmentation tool may induce significant inter-observer differences and BFR is not provided in the built-in software. In this work, we have developed an interactive tool to assess the retinal BFV and BFR in the macular region. Optical coherence tomography data was registered with the RFI image to locate the fovea accurately. The boundaries of the vessels were delineated on a motion contrast enhanced image and BFV was computed by maximizing the cross-correlation of pixel intensities in a ratio video. Furthermore, we were able to calculate the BFR in absolute values (μl/s). Experiments were conducted on 122 vessels from 5 healthy and 5 mild non-proliferative diabetic retinopathy (NPDR) subjects. The Pearson's correlation of the vessel diameter measurements between our method and manual labeling on 40 vessels was 0.984. The intraclass correlation (ICC) of BFV between our proposed method and built-in software was 0.924 and 0.830 for vessels from healthy and NPDR subjects, respectively. The coefficient of variation between repeated sessions was reduced significantly from 22.5% to 15.9% in our proposed method (p<0.001).

  8. [Age-related macular degeneration as a local manifestation of atherosclerosis - a novel insight into pathogenesis].

    PubMed

    Machalińska, Anna

    2013-01-01

    Age-related macular degeneration is the leading cause of irreversible visual impairment and disability among the elderly in developed countries. There is compelling evidence that atherosclerosis and age-related macular degeneration share a similar pathogenic process. The association between atherosclerosis and age-related macular degeneration has been inferred from histological, biochemical and epidemiological studies. Many published data indicate that drusen are similar in molecular composition to plaques in atherosclerosis. Furthermore, a great body of evidence has emerged over the past decade that implicates the chronic inflammatory processes in the pathogenesis and progression of both disorders. We speculate that vascular atherosclerosis and age-related macular degeneration may represent different manifestations of the same disease induced by a pathologic tissue response to the damage caused by oxidative stress and local ischemia. In this review, we characterise in detail a strong association between age-related macular degeneration and atherosclerosis development, and we postulate the hypothesis that age-related macular degeneration is a local manifestation of a systemic disease. This provides a new approach for understanding the aspects of pathogenesis and might improve the prevention and treatment of both diseases which both result from ageing of the human body.

  9. Arginine-Restricted Therapy Resistant Bilateral Macular Edema Associated with Gyrate Atrophy.

    PubMed

    Doguizi, Sibel; Sekeroglu, Mehmet Ali; Anayol, Mustafa Alpaslan; Yilmazbas, Pelin

    2015-01-01

    Introduction. Gyrate atrophy is a rare genetical metabolic disorder affecting vision. Here, we report a 9-year-old boy with gyrate atrophy associated with bilateral macular edema at the time of diagnosis and the effect of long term metabolic control on macular edema. Case Presentation. A 9-year-old boy presented with a complaint of low visual acuity (best corrected visual acuity: 20/80 in both eyes, refractive error: -12.00 D). Dilated fundus examination revealed multiple bilateral, sharply defined, and scalloped chorioretinal atrophy areas in the midperipheral and peripheral zone. Spectral-domain optical coherence tomography revealed bilateral cystoid macular edema in both eyes. Serum ornithine level was high (622 μmol/L). An arginine-restricted diet reduced serum ornithine level (55 μmol/L). However, visual findings including macular edema remained unchanged in 2 years of follow-up. Conclusion. Arginine-restricted diet did not improve macular edema in our patient with gyrate atrophy. A more comprehensive understanding of the underlying factors for macular edema will lead to the development of effective therapies.

  10. Macular Edema After Cataract Surgery In Eyes Without Pre-operative Central-involved Diabetic Macular Edema

    PubMed Central

    Baker, Carl W.; Almukhtar, Talat; Bressler, Neil M.; Glassman, Adam R.; Grover, Sandeep; Kim, Stephen J.; Murtha, Timothy J.; Rauser, Michael E.; Stockdale, Cynthia

    2014-01-01

    Objective To estimate the incidence of central-involved macular edema (ME)16 weeks following cataract surgery in eyes with diabetic retinopathy (DR) without definite central-involved diabetic macular edema (DME) preoperatively. Methods In a multicenter, prospective, observational study, participants (N = 293) with DR without definite OCT central subfield (CSF) thickening underwent cataract surgery. The primary outcome was development of central-involved ME defined as; (1) OCT CSF thickness ≥ 250μm (time domain) or ≥ 310μm (spectral domain) with ≥1 step increase in logOCT CSF thickness pre-operative to the 16-week visit; (2) ≥2-step increase in logOCT CSF pre-operative to 16-week visit; or (3) non-topical treatment for ME received before the 16-week visit with either of the OCT criteria met at the time of treatment. Results Median participant age was 64 years with median visual acuity letter score of 69 (Snellen equivalent 20/40). Forty-four percent of eyes had history of prior treatment for DME. Sixteen weeks postoperatively, central-involved ME was noted in 0% (95%CI: 0-20%) of 17 eyes with no pre-operative DME. Of eyes with non-central involved DME, 10% (95%CI: 5-18%) of 97 eyes without central involved DME and 12% (95%CI: 7-19%) of 147 eyes with possible central involved DME at baseline progressed to central-involved ME. History of DME treatment was significantly associated with central-involved ME development (P<0.001). Conclusion In eyes with DR without concurrent central-involved DME, presence of non-central DME immediately prior to cataract surgery, or history of DME treatment, may increase risk of developing central-involved ME 16 weeks after cataract extraction. PMID:23599174

  11. CPT-hole closure

    USGS Publications Warehouse

    Noce, T.E.; Holzer, T.L.

    2003-01-01

    The long-term stability of deep holes 1.75 inches. (4.4 cm) in diameter by 98.4 feet (30 m) created by cone penetration testing (CPT) was monitored at a site in California underlain by Holocene and Pleistocene age alluvial fan deposits. Portions of the holes remained open both below and above the 28.6-foot (8.7 m)-deep water table for approximately three years, when the experiment was terminated. Hole closure appears to be a very slow process that may take decades in the stiff soils studied here. Other experience suggests holes in softer soils may also remain open. Thus, despite their small diameter, CPT holes may remain open for years and provide paths for rapid migration of contaminants. The observations confirm the need to grout holes created by CPT soundings as well as other direct-push techniques in areas where protection of shallow ground water is important.

  12. Quantization of Black Holes

    NASA Astrophysics Data System (ADS)

    He, Xiao-Gang; Ma, Bo-Qiang

    We show that black holes can be quantized in an intuitive and elegant way with results in agreement with conventional knowledge of black holes by using Bohr's idea of quantizing the motion of an electron inside the atom in quantum mechanics. We find that properties of black holes can also be derived from an ansatz of quantized entropy Δ S = 4π k Δ R/{{-{λ }}}, which was suggested in a previous work to unify the black hole entropy formula and Verlinde's conjecture to explain gravity as an entropic force. Such an Ansatz also explains gravity as an entropic force from quantum effect. This suggests a way to unify gravity with quantum theory. Several interesting and surprising results of black holes are given from which we predict the existence of primordial black holes ranging from Planck scale both in size and energy to big ones in size but with low energy behaviors.

  13. Naked black holes

    SciTech Connect

    Horowitz, G.T.; Ross, S.F.

    1997-08-01

    It is shown that there are large static black holes for which all curvature invariants are small near the event horizon, yet any object which falls in experiences enormous tidal forces {ital outside} the horizon. These black holes are charged and near extremality, and exist in a wide class of theories including string theory. The implications for cosmic censorship and the black hole information puzzle are discussed. {copyright} {ital 1997} {ital The American Physical Society}

  14. The Antarctic ozone hole

    NASA Technical Reports Server (NTRS)

    Molina, Mario J.

    1988-01-01

    Observations of Antarctic ozone levels and the discovery of a hole in the Antarctic region are examined. The effects of chlorofluorocarbons (CFCs) on the level of stratospheric ozone are analyzed. Three cycles explaining the cause of ozone depletion in the poles are proposed. A comparison of field data and proposed depletion cycles reveals that the chemical origin of the ozone hole is due to CFCs. The potential global effects of the Antarctic ozone hole are discussed.

  15. [Pharmacological therapy of age-related macular degeneration based on etiopathogenesis].

    PubMed

    Fischer, Tamás

    2015-11-15

    It is of great therapeutic significance that disordered function of the vascular endothelium which supply the affected ocular structures plays a major role in the pathogenesis and development of age-related macular degeneration. Chronic inflammation is closely linked to diseases associated with endothelial dysfunction, and age-related macular degeneration is accompanied by a general inflammatory response. According to current concept, age-related macular degeneration is a local manifestation of systemic vascular disease. This recognition could have therapeutic implications because restoration of endothelial dysfunction can restabilize the condition of chronic vascular disease including age-related macular degeneration as well. Restoration of endothelial dysfunction by pharmaacological or non pharmacological interventions may prevent the development or improve endothelial dysfunction, which result in prevention or improvement of age related macular degeneration as well. Medicines including inhibitors of the renin-angiotensin system (converting enzyme inhibitors, angiotensin-receptor blockers and renin inhibitors), statins, acetylsalicylic acid, trimetazidin, third generation beta-blockers, peroxisome proliferator-activated receptor gamma agonists, folate, vitamin D, melatonin, advanced glycation end-product crosslink breaker alagebrium, endothelin-receptor antagonist bosentan, coenzyme Q10; "causal" antioxidant vitamins, N-acetyl-cysteine, resveratrol, L-arginine, serotonin receptor agonists, tumor necrosis factor-alpha blockers, specific inhibitor of the complement alternative pathway, curcumin and doxycyclin all have beneficial effects on endothelial dysfunction. Restoration of endothelial dysfunction can restabilize chronic vascular disease including age-related macular degeneration as well. Considering that the human vascular system is consubstantial, medicines listed above should be given to patients (1) who have no macular degeneration but have risk factors

  16. [Pharmacological therapy of age-related macular degeneration based on etiopathogenesis].

    PubMed

    Fischer, Tamás

    2015-11-15

    It is of great therapeutic significance that disordered function of the vascular endothelium which supply the affected ocular structures plays a major role in the pathogenesis and development of age-related macular degeneration. Chronic inflammation is closely linked to diseases associated with endothelial dysfunction, and age-related macular degeneration is accompanied by a general inflammatory response. According to current concept, age-related macular degeneration is a local manifestation of systemic vascular disease. This recognition could have therapeutic implications because restoration of endothelial dysfunction can restabilize the condition of chronic vascular disease including age-related macular degeneration as well. Restoration of endothelial dysfunction by pharmaacological or non pharmacological interventions may prevent the development or improve endothelial dysfunction, which result in prevention or improvement of age related macular degeneration as well. Medicines including inhibitors of the renin-angiotensin system (converting enzyme inhibitors, angiotensin-receptor blockers and renin inhibitors), statins, acetylsalicylic acid, trimetazidin, third generation beta-blockers, peroxisome proliferator-activated receptor gamma agonists, folate, vitamin D, melatonin, advanced glycation end-product crosslink breaker alagebrium, endothelin-receptor antagonist bosentan, coenzyme Q10; "causal" antioxidant vitamins, N-acetyl-cysteine, resveratrol, L-arginine, serotonin receptor agonists, tumor necrosis factor-alpha blockers, specific inhibitor of the complement alternative pathway, curcumin and doxycyclin all have beneficial effects on endothelial dysfunction. Restoration of endothelial dysfunction can restabilize chronic vascular disease including age-related macular degeneration as well. Considering that the human vascular system is consubstantial, medicines listed above should be given to patients (1) who have no macular degeneration but have risk factors

  17. Open-hole fishing

    SciTech Connect

    Pietrobono, J.T.

    1988-01-01

    This paper reports on losing equipment in the hole that is one of the most expensive and potentially dangerous things that can go wrong in drilling a well. Drilling must come to a halt until the equipment is recovered, or the hole must be sidetracked. The well also can become hard to control with essential tools out of reach, increasing the risk of a blowout. Fishing, or recovering lost or stuck equipment in the hole, is therefore a critical procedure at any drilling operation. Fishing can be divided into two broad categories: open hole and cased hole. a major difference between the two is timing: open-hole fishing is done as the well is being drilled, whereas cased-hole fishing is performed during production or well workover. Fishing techniques and types of equipment used also vary between the tow. This lesson describes some of the basic techniques and tools used in open-hole fishing-that is, retrieving fish from a hole that is being drilled but is not yet cased.

  18. Macular thickness measured by stratus optical coherence tomography in patients with diabetes type 2 and mild nonproliferative retinopathy without clinical evidence of macular edema.

    PubMed

    Pires, Isabel; Santos, Ana Rita; Nunes, Sandrina; Lobo, Conceição

    2013-01-01

    To evaluate macular thickness in eyes with mild nonproliferative diabetic retinopathy (NPDR), patients with diabetes type 2, NPDR level 20 or 35, and without evidence of clinical macular edema underwent best-corrected visual acuity assessment, color fundus photography and Stratus optical coherence tomography. Mean center point thickness (CPT) and mean central subfield (CSF) thickness were compared with those of a healthy control population. 410 eyes/patients aged 61.2 ± 8.3 years, and with glycosylated hemoglobin of 7.9 ± 1.5% were included. Mean CPT and CSF were 186.6 ± 28.4 and 215.2 ± 25 µm, respectively, significantly increased compared to healthy subjects (p < 0.001). CSF thickness was abnormally increased in 17.6% of the patients, with values within the normal range in 79.5%, and abnormally decreased in 2.9%. CPT and CSF thickness were significantly thicker in men. No systemic factors showed a significant association. A significant increase in the macular thickness was found in eyes/patients with mild NPDR without clinical macular edema; however, only 17.6% of the eyes/patients had abnormally increased values and less than 3% abnormally decreased values.

  19. Newborn Black Holes

    ERIC Educational Resources Information Center

    Science Teacher, 2005

    2005-01-01

    Scientists using NASA's Swift satellite say they have found newborn black holes, just seconds old, in a confused state of existence. The holes are consuming material falling into them while somehow propelling other material away at great speeds. "First comes a blast of gamma rays followed by intense pulses of x-rays. The energies involved are much…

  20. Can we track holes?

    PubMed Central

    Horowitz, Todd S.; Kuzmova, Yoana

    2011-01-01

    The evidence is mixed as to whether the visual system treats objects and holes differently. We used a multiple object tracking task to test the hypothesis that figural objects are easier to track than holes. Observers tracked four of eight items (holes or objects). We used an adaptive algorithm to estimate the speed allowing 75% tracking accuracy. In Experiments 1–5, the distinction between holes and figures was accomplished by pictorial cues, while red-cyan anaglyphs were used to provide the illusion of depth in Experiment 6. We variously used Gaussian pixel noise, photographic scenes, or synthetic textures as backgrounds. Tracking was more difficult when a complex background was visible, as opposed to a blank background. Tracking was easier when disks carried fixed, unique markings. When these factors were controlled for, tracking holes was no more difficult than tracking figures, suggesting that they are equivalent stimuli for tracking purposes. PMID:21334361

  1. Hole-ness of point clouds

    NASA Astrophysics Data System (ADS)

    Gronz, Oliver; Seeger, Manuel; Klaes, Björn; Casper, Markus C.; Ries, Johannes B.

    2015-04-01

    Accurate and dense 3D models of soil surfaces can be used in various ways: They can be used as initial shapes for erosion models. They can be used as benchmark shapes for erosion model outputs. They can be used to derive metrics, such as random roughness... One easy and low-cost method to produce these models is structure from motion (SfM). Using this method, two questions arise: Does the soil moisture, which changes the colour, albedo and reflectivity of the soil, influence the model quality? How can the model quality be evaluated? To answer these questions, a suitable data set has been produced: soil has been placed on a tray and areas with different roughness structures have been formed. For different moisture states - dry, medium, saturated - and two different lighting conditions - direct and indirect - sets of high-resolution images at the same camera positions have been taken. From the six image sets, 3D point clouds have been produced using VisualSfM. The visual inspection of the 3D models showed that all models have different areas, where holes of different sizes occur. But it is obviously a subjective task to determine the model's quality by visual inspection. One typical approach to evaluate model quality objectively is to estimate the point density on a regular, two-dimensional grid: the number of 3D points in each grid cell projected on a plane is calculated. This works well for surfaces that do not show vertical structures. Along vertical structures, many points will be projected on the same grid cell and thus the point density rather depends on the shape of the surface but less on the quality of the model. Another approach has been applied by using the points resulting from Poisson Surface Reconstructions. One of this algorithm's properties is the filling of holes: new points are interpolated inside the holes. Using the original 3D point cloud and the interpolated Poisson point set, two analyses have been performed: For all Poisson points, the

  2. [Early macular edema after phacoemulsification and suspected overdose of cefuroxime: report of six cases].

    PubMed

    Le Dû, B; Pierre-Kahn, V

    2014-03-01

    Antibiotic prophylaxis by intracameral cefuroxime injection, 1mg/0.1 mL after cataract surgery is increasing in popularity. Several cases of early postoperative macular edema have recently been reported after cefuroxime injection, most of them due to accidental cefuroxime overdose. We report six additional cases of macular involvement after cataract surgery, with intracameral cefuroxime injection imputed to cause retinal toxicity. Formal proof of cefuroxime overdose has never been possible, due to rapid wash-out in a few hours and the diagnosis of the macular edema the day after surgery or within a few days. Thus, this strong suspicion is based on clinical, pharmacokinetic, tomographic and retinographic criteria. In our series of six cases, the first four patients involved the same surgeon in the same hospital, and two of them on the same day. For the sixth case, the diagnosis was made retrospectively and based on history and medium-term tomographic characteristics. All the patients underwent optical coherence tomography (OCT) relatively early. As early as day one after surgery, there is macular edema predominantly in the outer retinal layers associated with serous retinal detachment, similar to the cases described in the literature. In the late stage, three patients had functional impairment related to photoreceptor damage on OCT. Three cases are described with additional retinal imaging (angiography, autofluorescence) to better characterize this macular toxicity associated with cefuroxime.

  3. Macular findings on optical coherence tomography in cat-scratch disease neuroretinitis

    PubMed Central

    Habot-Wilner, Z; Zur, D; Goldstein, M; Goldenberg, D; Shulman, S; Kesler, A; Giladi, M; Neudorfer, M

    2011-01-01

    Purpose To describe the macular findings on optical coherence tomography (OCT) in patients with cat-scratch disease (CSD) neuroretinitis. Methods Medical records of all patients diagnosed with CSD neuroretinitis at the Tel Aviv Medical Center between April 2006 and May 2010 were retrospectively reviewed. All patients underwent Stratus OCT macular examination. Results Eight eyes of seven patients with confirmed CSD neuroretinitis, (mean age 33±9.9 years, range 6–48 years) were included in the study. All patients presented clinically with optic nerve swelling and macular edema or macular exudates. OCT demonstrated flattening of the foveal contour, thickening of the neurosensory retina, and accumulation of subretinal fluid (SRF) in all studied eyes. Retinal exudates appeared as multiple hyper-reflective foci in the outer plexiform layer. The average central macular thickness was 460 μm (range 170–906 μm) and the average maximal retinal thickness was 613 μm (range 387–1103 μm), at presentation. The macula appeared normal on repeated exams during follow-up. Conclusion Similar OCT findings were demonstrated in patients with CSD neuroretinitis. SRF was found in all eyes, although was not visible on clinical examination or fluorescein angiography. OCT may be used as an adjunct imaging tool in the diagnosis and follow-up of patients with CSD neuroretinitis. PMID:21660065

  4. Age-Related Macular Degeneration: A Scientometric Analysis

    PubMed Central

    Ramin, Shahrokh; Soheilian, Masoud; Habibi, Gholamreza; Ghazavi, Roghayeh; Gharebaghi, Reza; Heidary, Fatemeh

    2015-01-01

    Age-related macular degeneration (ARMD) is a major cause of central blindness among working aged adults across the world. Systematic research planning on any subject, including ARMD is in need of solid data regarding previous efforts in this field and to identify the gaps in the research. This study aimed to elucidate the most important trends, directions, and gap in this subject. The data extracted from the Institute for Scientific Information were used to perform a bibliometric analysis of the scientific productions (1993–2013) about ARMD. Specific parameters related to ARMD were analyzed to obtain a view of the topic’s structure, history, and document relationships. Additionally, the trends and authors in the most influential publications were analyzed. The number of articles in this field was found constantly increasing. Most highly cited articles addressed genetic epidemiology and clinical research topics in this field. During the past 3 years, there has been a trend toward biomarker research. Through performing the first scientometric survey on ARMD research, we analyzed the characteristics of papers and the trends in scientific production. We also identified some of the critical gaps in the current research efforts that would help in large-scale research strategic planning. PMID:26060829

  5. Bilateral Macular Roth Spots as a Manifestation of Subacute Endocarditis.

    PubMed

    Ceglowska, Karolina; Nowomiejska, Katarzyna; Kiszka, Agnieszka; Koss, Michael J; Maciejewski, Ryszard; Rejdak, Robert

    2015-01-01

    A 42-year-old man presented with a 2-day history of impaired vision in the right eye (OD). The best corrected visual acuity (BCVA) (LogMAR) was 1.1 for the right eye and 0.0 for the left eye (OS). Fundus examination revealed white-centered hemorrhages resembling Roth spots in both macular regions. The spectral-domain optical coherence tomography (SD-OCT) showed intraretinal pseudocysts and hyperreflective deposits in the areas corresponding to the Roth spots. Conducted blood tests revealed elevated D-dimer concentration, increased total number of neutrophils, high C-reactive protein concentration, and elevated erythrocyte sedimentation rate. Procalcitonin concentration, platelet count, and body temperature were within normal ranges. A blood culture was ordered and yielded Streptococcus mitis and intravenous antibiotics were started immediately. The patient started complaining of chest and left calf pain. The systemic examination revealed infective endocarditis accompanied by bicuspid aortic valve and paravalvular abscess formation. The patient underwent cardiac surgery with mechanical aortic valve implantation. After recovery, the patient's visual acuities improved fully. Control ophthalmic examination, including SD-OCT, showed no abnormalities. PMID:26839725

  6. Promising new treatments for neovascular age-related macular degeneration.

    PubMed

    Michels, Stephan; Schmidt-Erfurth, Ursula; Rosenfeld, Philip J

    2006-07-01

    Angiogenesis, the growth of new blood vessels from existing blood vessels, is responsible for vision loss in a variety of ophthalmic diseases. In neovascular age-related macular degeneration (AMD), the leading cause for legal blindness in many industrialised countries, abnormal blood vessels grow in the macula and cause blindness. There are a number of factors important in the angiogenic cascade but VEGF-A has been implicated in recent years as the major factor responsible for neovascular and exudative diseases of the eye. Numerous antiangiogenic drugs are in development but anti-VEGF drugs have shown great promise in treating neovascular AMD and other ocular diseases, and many of these drugs have been adopted from oncology where antiangiogenic therapy is gaining wide acceptance. For the first time in neovascular AMD, anti-VEGF drugs have brought the hope of vision improvement to a significant proportion of patients. This review provides an overview on angiogenic mechanisms, potential antiangiogenic treatment strategies and different antiangiogenic drugs with special focus on neovascular AMD.

  7. Radiation therapy for neovascular age-related macular degeneration

    PubMed Central

    Petrarca, Robert; Jackson, Timothy L

    2011-01-01

    Antivascular endothelial growth factor (anti-VEGF) therapies represent the standard of care for most patients presenting with neovascular (wet) age-related macular degeneration (neovascular AMD). Anti-VEGF drugs require repeated injections and impose a considerable burden of care, and not all patients respond. Radiation targets the proliferating cells that cause neovascular AMD, including fibroblastic, inflammatory, and endothelial cells. Two new neovascular AMD radiation treatments are being investigated: epimacular brachytherapy and stereotactic radiosurgery. Epimacular brachytherapy uses beta radiation, delivered to the lesion via a pars plana vitrectomy. Stereotactic radiosurgery uses low voltage X-rays in overlapping beams, directed onto the lesion. Feasibility data for epimacular brachytherapy show a greatly reduced need for anti-VEGF therapy, with a mean vision gain of 8.9 ETDRS letters at 12 months. Pivotal trials are underway (MERLOT, CABERNET). Preliminary stereotactic radiosurgery data suggest a mean vision gain of 8 to 10 ETDRS letters at 12 months. A large randomized sham controlled stereotactic radiosurgery feasibility study is underway (CLH002), with pivotal trials to follow. While it is too early to conclude on the safety and efficacy of epimacular brachytherapy and stereotactic radiosurgery, preliminary results are positive, and these suggest that radiation offers a more durable therapeutic effect than intraocular injections. PMID:21311657

  8. Review of nutrient actions on age-related macular degeneration.

    PubMed

    Zampatti, Stefania; Ricci, Federico; Cusumano, Andrea; Marsella, Luigi Tonino; Novelli, Giuseppe; Giardina, Emiliano

    2014-02-01

    The actions of nutrients and related compounds on age-related macular degeneration (AMD) are explained in this review. The findings from 80 studies published since 2003 on the association between diet and supplements in AMD were reviewed. Antioxidants and other nutrients with an effect on AMD susceptibility include carotenoids (lutein and zeaxanthin, β-carotene), vitamins (vitamin A, E, C, D, B), mineral supplements (zinc, copper, selenium), dietary fatty acids [monounsaturated fatty acids, polyunsaturated fatty acids (PUFA both omega-3 PUFA and omega-6 PUFA), saturated fatty acids and cholesterol], and dietary carbohydrates. The literature revealed that many of these antioxidants and nutrients exert a protective role by functioning synergistically. Specifically, the use of dietary supplements with targeted actions can provide minimal benefits on the onset or progression of AMD; however, this does not appear to be particularly beneficial in healthy people. Furthermore, some supplements or nutrients have demonstrated discordant effects on AMD in some studies. Since intake of dietary supplements, as well as exposure to damaging environmental factors, is largely dependent on population habits (including dietary practices) and geographical localization, an overall healthy diet appears to be the best strategy in reducing the risk of developing AMD. As of now, the precise mechanism of action of certain nutrients in AMD prevention remains unclear. Thus, future studies are required to examine the effects that nutrients have on AMD and to determine which factors are most strongly correlated with reducing the risk of AMD or preventing its progression. PMID:24461310

  9. Bilateral Macular Roth Spots as a Manifestation of Subacute Endocarditis

    PubMed Central

    Ceglowska, Karolina; Nowomiejska, Katarzyna; Kiszka, Agnieszka; Koss, Michael J.; Maciejewski, Ryszard; Rejdak, Robert

    2015-01-01

    A 42-year-old man presented with a 2-day history of impaired vision in the right eye (OD). The best corrected visual acuity (BCVA) (LogMAR) was 1.1 for the right eye and 0.0 for the left eye (OS). Fundus examination revealed white-centered hemorrhages resembling Roth spots in both macular regions. The spectral-domain optical coherence tomography (SD-OCT) showed intraretinal pseudocysts and hyperreflective deposits in the areas corresponding to the Roth spots. Conducted blood tests revealed elevated D-dimer concentration, increased total number of neutrophils, high C-reactive protein concentration, and elevated erythrocyte sedimentation rate. Procalcitonin concentration, platelet count, and body temperature were within normal ranges. A blood culture was ordered and yielded Streptococcus mitis and intravenous antibiotics were started immediately. The patient started complaining of chest and left calf pain. The systemic examination revealed infective endocarditis accompanied by bicuspid aortic valve and paravalvular abscess formation. The patient underwent cardiac surgery with mechanical aortic valve implantation. After recovery, the patient's visual acuities improved fully. Control ophthalmic examination, including SD-OCT, showed no abnormalities. PMID:26839725

  10. Automatic age-related macular degeneration detection and staging

    NASA Astrophysics Data System (ADS)

    van Grinsven, Mark J. J. P.; Lechanteur, Yara T. E.; van de Ven, Johannes P. H.; van Ginneken, Bram; Theelen, Thomas; Sánchez, Clara I.

    2013-03-01

    Age-related macular degeneration (AMD) is a degenerative disorder of the central part of the retina, which mainly affects older people and leads to permanent loss of vision in advanced stages of the disease. AMD grading of non-advanced AMD patients allows risk assessment for the development of advanced AMD and enables timely treatment of patients, to prevent vision loss. AMD grading is currently performed manually on color fundus images, which is time consuming and expensive. In this paper, we propose a supervised classification method to distinguish patients at high risk to develop advanced AMD from low risk patients and provide an exact AMD stage determination. The method is based on the analysis of the number and size of drusen on color fundus images, as drusen are the early characteristics of AMD. An automatic drusen detection algorithm is used to detect all drusen. A weighted histogram of the detected drusen is constructed to summarize the drusen extension and size and fed into a random forest classifier in order to separate low risk from high risk patients and to allow exact AMD stage determination. Experiments showed that the proposed method achieved similar performance as human observers in distinguishing low risk from high risk AMD patients, obtaining areas under the Receiver Operating Characteristic curve of 0.929 and 0.934. A weighted kappa agreement of 0.641 and 0.622 versus two observers were obtained for AMD stage evaluation. Our method allows for quick and reliable AMD staging at low costs.

  11. Modifiable risk factors for age-related macular degeneration.

    PubMed

    Guymer, Robyn H; Chong, Elaine Wei-Tinn

    2006-05-01

    Age-related macular degeneration (AMD) is the leading cause of irreversible blindness in Australia and other Western countries. As there is no cure for AMD, and treatments to stop its progression have met with limited success, there is an interest in identifying modifiable risk factors to prevent or slow disease progression. To date, smoking is the only proven modifiable risk factor for AMD. Other factors under study include (i) cardiovascular risk factors such as hypertension, body mass index, and atherosclerosis; and (ii) dietary risk factors including fat and antioxidant intake, but so far these studies have produced conflicting results. Dietary fat in relation to AMD has recently attracted media attention. Despite very limited work supporting an association between vegetable fat and AMD, widespread publicity advocating margarine as a cause of AMD and encouraging use of butter instead has caused confusion and anxiety among sufferers of AMD and the general public, as well as concern among health professionals. The antioxidant carotenoids--lutein and zeaxanthin--found in dark green or yellow vegetables exist in high concentrations in the macula and are hypothesised to play a protective role. Of nine controlled trials of supplementation with carotenoids and other antioxidants, three suggested that various combinations of antioxidants and carotenoids were protective. While a low-fat diet rich in dark green and yellow vegetables is advocated in general, any specific recommendations regarding certain fats or antioxidant supplementation and AMD are not based on consistent findings at this stage. PMID:16646746

  12. Eye Conditions in Older Adults: Age-Related Macular Degeneration.

    PubMed

    Iroku-Malize, Tochi; Kirsch, Scott

    2016-06-01

    Age-related macular degeneration (AMD) causes a progressive loss of photoreceptors in the macula. It is the most common cause of legal blindness in the United States, and some form of AMD is thought to affect more than 9 million individuals. Risk factors include older age, smoking, dyslipidemia, obesity, white race, female sex, and a family history of AMD. There are two types of advanced AMD: nonexudative (dry or geographic atrophy) and exudative (wet or neovascular). Both cause progressive central vision loss with intact peripheral vision. Nonexudative AMD accounts for 80% to 90% of all advanced cases, and more than 90% of patients with severe vision loss have exudative AMD. On ophthalmoscopic examination, early findings include drusen (ie, yellow deposits in the retina). Prominent choroidal vessels, subretinal edema, and/or hemorrhage are seen in wet AMD. Regular eye examinations, visual field testing, fluorescein angiography, and optical coherence tomography are used for diagnosis and to guide management. There is no specific therapy for dry AMD, but antioxidant supplementation may be helpful. Intravitreal injection of a vascular endothelial growth factor inhibitor is the treatment of choice for wet AMD. Optical aids and devices can help to maximize function for patients with AMD. PMID:27348529

  13. Current therapeutic developments in atrophic age-related macular degeneration.

    PubMed

    Hanus, Jakub; Zhao, Fangkun; Wang, Shusheng

    2016-01-01

    Age-related macular degeneration (AMD), a degenerative disorder of the central retina, is the leading cause of irreversible blindness in the elderly. The underlying mechanism of the advanced form of dry AMD, also named geographic atrophy (GA) or atrophic AMD, remains unclear. Consequently, no cure is available for dry AMD or GA. The only prevention option currently available is the Age-Related Eye Disease Study (AREDS) formulation, which has been demonstrated to slow down the progression of dry AMD. This review summarises recent advances in therapy for dry AMD and GA. Building on the new understanding of the disease and recent technological breakthroughs, numerous ongoing clinical trials have the goal of meeting the need to cure AMD. Therapeutic agents are being developed to target the key features of the disease, including inhibiting the complement pathway and other inflammatory pathways, reducing oxidative stress and protecting retinal pigment epithelial (RPE) cells, inhibiting lipofuscin and visual cycle, regenerating RPE cells from stem cells and restoring choroidal blood flow. Some of these therapeutic options, especially the stem cell-based therapy, hold great promise, which brings great hope for this devastating blinding disease. PMID:26553922

  14. Idiopathic eruptive macular pigmentation in a child with citrin deficiency.

    PubMed

    Fu, Chu-Li; Hu, Yun-Feng; Song, Yuan-Zong

    2016-09-01

    Idiopathic eruptive macular pigmentation (IEMP) is a rare dermatological disorder with generally unclear etiology and pathogenesis. A 5½-year-old girl was referred to hospital with a 10 month history of brown skin rashes. In early infancy, citrin deficiency had been diagnosed with the SLC25A13 genotype c.851_854del4/c.998G > A, but all clinical and laboratory abnormalities recovered following the introduction of a lactose-free and medium-chain triglyceride-enriched formula. Physical examination at referral indicated symmetric, multiple and non-scaly brown macules on the neck, trunk, buttocks and proximal parts of the extremities. Histopathology indicated epidermal basal layer hyperpigmentation with an irregular distribution, along with a large number of melanophages in the upper dermis. The diagnosis of IEMP was thus made. Within 2 years of follow up, the rashes disappeared spontaneously and gradually. To our knowledge, this is the first description of IEMP in a patient with silent citrin deficiency. PMID:27389718

  15. Microcystic macular edema detection in retina OCT images

    NASA Astrophysics Data System (ADS)

    Swingle, Emily K.; Lang, Andrew; Carass, Aaron; Ying, Howard S.; Calabresi, Peter A.; Prince, Jerry L.

    2014-03-01

    Optical coherence tomography (OCT) is a powerful imaging tool that is particularly useful for exploring retinal abnormalities in ophthalmological diseases. Recently, it has been used to track changes in the eye associated with neurological diseases such as multiple sclerosis (MS) where certain tissue layer thicknesses have been associated with disease progression. A small percentage of MS patients also exhibit what has been called microcystic macular edema (MME), where uid collections that are thought to be pseudocysts appear in the inner nuclear layer. Very little is known about the cause of this condition so it is important to be able to identify precisely where these pseudocysts occur within the retina. This identi cation would be an important rst step towards furthering our understanding. In this work, we present a detection algorithm to nd these pseudocysts and to report on their spatial distribution. Our approach uses a random forest classi er trained on manual segmentation data to classify each voxel as pseudocyst or not. Despite having a small sample size of ve subjects, the algorithm correctly identi es 84.6% of pseudocysts as compared to manual delineation. Finally, using our method, we show that the spatial distribution of pseudocysts within the macula are generally contained within an annulus around the fovea.

  16. Seven New Loci Associated with Age-Related Macular Degeneration

    PubMed Central

    2013-01-01

    Age-related macular degeneration (AMD) is a common cause of blindness in older individuals. To accelerate understanding of AMD biology and help design new therapies, we executed a collaborative genomewide association study, examining >17,100 advanced AMD cases and >60,000 controls of European and Asian ancestry. We identified 19 genomic loci associated with AMD with p<5×10−8 and enriched for genes involved in regulation of complement activity, lipid metabolism, extracellular matrix remodeling and angiogenesis. Our results include 7 loci reaching p<5×10−8 for the first time, near the genes COL8A1/FILIP1L, IER3/DDR1, SLC16A8, TGFBR1, RAD51B, ADAMTS9/MIR548A2, and B3GALTL. A genetic risk score combining SNPs from all loci displayed similar good ability to distinguish cases and controls in all samples examined. Our findings provide new directions for biological, genetic and therapeutic studies of AMD. PMID:23455636

  17. Age-Related Macular Degeneration: A Scientometric Analysis.

    PubMed

    Ramin, Shahrokh; Soheilian, Masoud; Habibi, Gholamreza; Ghazavi, Roghayeh; Gharebaghi, Reza; Heidary, Fatemeh

    2015-01-01

    Age-related macular degeneration (ARMD) is a major cause of central blindness among working aged adults across the world. Systematic research planning on any subject, including ARMD is in need of solid data regarding previous efforts in this field and to identify the gaps in the research. This study aimed to elucidate the most important trends, directions, and gap in this subject. The data extracted from the Institute for Scientific Information were used to perform a bibliometric analysis of the scientific productions (1993-2013) about ARMD. Specific parameters related to ARMD were analyzed to obtain a view of the topic's structure, history, and document relationships. Additionally, the trends and authors in the most influential publications were analyzed. The number of articles in this field was found constantly increasing. Most highly cited articles addressed genetic epidemiology and clinical research topics in this field. During the past 3 years, there has been a trend toward biomarker research. Through performing the first scientometric survey on ARMD research, we analyzed the characteristics of papers and the trends in scientific production. We also identified some of the critical gaps in the current research efforts that would help in large-scale research strategic planning. PMID:26060829

  18. Age-Related Macular Degeneration: A Scientometric Analysis.

    PubMed

    Ramin, Shahrokh; Soheilian, Masoud; Habibi, Gholamreza; Ghazavi, Roghayeh; Gharebaghi, Reza; Heidary, Fatemeh

    2015-01-01

    Age-related macular degeneration (ARMD) is a major cause of central blindness among working aged adults across the world. Systematic research planning on any subject, including ARMD is in need of solid data regarding previous efforts in this field and to identify the gaps in the research. This study aimed to elucidate the most important trends, directions, and gap in this subject. The data extracted from the Institute for Scientific Information were used to perform a bibliometric analysis of the scientific productions (1993-2013) about ARMD. Specific parameters related to ARMD were analyzed to obtain a view of the topic's structure, history, and document relationships. Additionally, the trends and authors in the most influential publications were analyzed. The number of articles in this field was found constantly increasing. Most highly cited articles addressed genetic epidemiology and clinical research topics in this field. During the past 3 years, there has been a trend toward biomarker research. Through performing the first scientometric survey on ARMD research, we analyzed the characteristics of papers and the trends in scientific production. We also identified some of the critical gaps in the current research efforts that would help in large-scale research strategic planning.

  19. Nutritional Risk Factors for Age-Related Macular Degeneration

    PubMed Central

    Ersoy, Lebriz; Lechanteur, Yara T.; Hoyng, Carel B.; Kirchhof, Bernd; den Hollander, Anneke I.

    2014-01-01

    Purpose. To evaluate the role of nutritional factors, serum lipids, and lipoproteins in late age-related macular degeneration (late AMD). Methods. Intake of red meat, fruit, fish, vegetables, and alcohol, smoking status, and body mass index (BMI) were ascertained questionnaire-based in 1147 late AMD cases and 1773 controls from the European Genetic Database. Serum levels of lipids and lipoproteins were determined. The relationship between nutritional factors and late AMD was assessed using logistic regression. Based on multivariate analysis, area-under-the-curve (AUC) was calculated by receiver-operating-characteristics (ROC). Results. In a multivariate analysis, besides age and smoking, obesity (odds ratio (OR): 1.44, P = 0.014) and red meat intake (daily: OR: 2.34, P = 8.22 × 10−6; 2–6x/week: OR: 1.67, P = 7.98 × 10−5) were identified as risk factors for developing late AMD. Fruit intake showed a protective effect (daily: OR: 0.52, P = 0.005; 2–6x/week: OR: 0.58, P = 0.035). Serum lipid and lipoprotein levels showed no significant association with late AMD. ROC for nutritional factors, smoking, age, and BMI revealed an AUC of 0.781. Conclusion. Red meat intake and obesity were independently associated with increased risk for late AMD, whereas fruit intake was protective. A better understanding of nutritional risk factors is necessary for the prevention of AMD. PMID:25101280

  20. Microaneurysms cause refractory macular edema in branch retinal vein occlusion

    PubMed Central

    Tomiyasu, Taneto; Hirano, Yoshio; Yoshida, Munenori; Suzuki, Norihiro; Nishiyama, Takeshi; Uemura, Akiyoshi; Yasukawa, Tsutomu; Ogura, Yuichiro

    2016-01-01

    Intravitreal anti-vascular endothelial growth factor (VEGF) agents can treat macular edema (ME) in branch retinal vein occlusion (BRVO). However, refractory ME, the mechanism of which is not well elucidated, occurs frequently. Sixty-six eyes with ME secondary to BRVO were enrolled in this retrospective observational case-control study. Twenty eyes received a sub-Tenon’s capsule injection of triamcinolone acetonide (STTA), 22 eyes an intravitreal anti-VEGF injection (ranibizumab), 16 eyes were switched from STTA to ranibizumab, 4 eyes underwent vitrectomy, and 4 eyes were untreated. Multiple regression analysis and multivariate logistic regression analysis were conducted, respectively, to identify independent predictors of visual acuity (VA) prognosis and risk factors for refractory ME longer than 1 year. The mechanism of refractory ME and therapeutic approaches for identified risk factors also were investigated. Thirty-four (52%) eyes had refractory ME for over 1 year. Microaneurysms were identified as risk factors for refractory ME, leading to poor final VA. Ranibizumab suppressed microaneurysm formation and refractory ME, with early administration more effective. For already formed microaneurysms, laser photocoagulation reduced additional treatments. Microaneurysms may cause refractory ME in BRVO. Alternative therapy to suppress microaneurysms should be considered to prevent refractory ME in patients with BRVO. PMID:27389770

  1. Updates on the Clinical Trials in Diabetic Macular Edema.

    PubMed

    Demirel, Sibel; Argo, Colby; Agarwal, Aniruddha; Parriott, Jacob; Sepah, Yasir Jamal; Do, Diana V; Nguyen, Quan Dong

    2016-01-01

    In this era of evidence-based medicine, significant progress has been made in the field of pharmacotherapeutics for the management of diabetic macular edema (DME). A. number of landmark clinical trials have provided strong evidence of the safety and efficacy of agents such as anti-vascular endothelial growth factors for the treatment of DME. Decades of clinical research, ranging from the early treatment of diabetic retinopathy study to the present-day randomized clinical trials (RCTs) testing novel agents, have shifted the goal of therapy from preventing vision loss to ensuring a maximum visual gain. Systematic study designs have provided robust data with an attempt to optimize the treatment regimens including the choice of the agent and timing of therapy. However, due to a number of challenges in the management of DME with approved agents, further studies are needed. For the purpose of this review, an extensive database search in English language was performed to identify prospective, RCTs testing pharmacological agents for DME. In order to acquaint the reader with the most relevant data from these clinical trials, this review focuses on pharmacological agents that are currently approved or have widespread applications in the management of DME. An update on clinical trials presently underway for DME has also been provided.

  2. Prevalence of age-related macular degeneration among the elderly

    PubMed Central

    Rasoulinejad, Seyed Ahmad; Zarghami, Amin; Hosseini, Seyed Reza; Rajaee, Neda; Rasoulinejad, Seyed Elahe; Mikaniki, Ebrahim

    2015-01-01

    Background: Age-related macular degeneration (AMD) is the leading cause of visual impairment and blindness in elderly population in the developing countries. Previous epidemiological studies revealed various potential modifiable risk factors for this disease. The purpose of this study was to evaluate the prevalence of AMD among elderly living in Babol, North of Iran. Methods: The study population of this cross-sectional study came from the Amirkola Health and Ageing Project (AHAP), the first comprehensive cohort study of the health of people aged 60 years and over in Amirkola, North of Iran. The prevalence of AMD was estimated and its risk was determined using logistic regression analysis (LRA) with regard to variables such as smoking, hyperlipidemia, hypertension and diabetes. Results: Five hundred and five participants with mean age of 71.55±5.9 (ranged 60-89) years entered the study. The prevalence of AMD was 17.6%. There was a significant association between AMD and smoking (P<0.001) but no association was seen with AMD and age, level of education, history of hyperlipidemia, hypertension and diabetes. Multiple LRAs revealed that smoking increased AMD by odds ratio of 5.03 (95% confidence interval 2.47-10.23 p<0.001) as compared to nonsmokers Conclusion: According to our findings, the prevalence of AMD was relatively high and smoking increased the risk of AMD in the elderly population. PMID:26644880

  3. Current Therapeutic Development for Atrophic Age-related Macular Degeneration

    PubMed Central

    Hanus, Jakub; Zhao, Fangkun; Wang, Shusheng

    2016-01-01

    Age-related macular degeneration (AMD), a degenerative disorder of the central retina, is the leading cause of irreversible blindness in the elderly. The underlying mechanism of the advanced form of dry AMD, also named geographic atrophy (GA) or atrophic AMD, remains unclear. Consequently, no cure is available for dry AMD or GA. The only prevention option currently available is the Age Related Eye Disease Study (AREDS) formulation which has been demonstrated to slow down the progression of dry AMD. This review summarizes recent advances in therapy for dry AMD and GA. Building on the new understanding of the disease and recent technological breakthroughs, numerous ongoing clinical trials have the goal of meeting the need to cure AMD. Therapeutic agents are being developed to target the key features of the disease, including inhibiting the complement pathway and other inflammatory pathways, reducing oxidative stress and protecting retinal pigment epithelial (RPE) cells, inhibiting lipofuscin and visual cycle, regenerating RPE cells from stem cells and restoring choroidal blood flow. Some of these therapeutic options, especially the stem-cell based therapy, hold great promise, which brings great hope for this devastating blinding disease. PMID:26553922

  4. Diabetic Macular Edema: From Old Concepts to New Therapeutic Avenues

    PubMed Central

    Mansour, Ahmad M; Pulido, Jose S; Arevalo, J Fernando

    2015-01-01

    Diabetic macular edema (DME) is a significant cause of blindness in the working population and is currently challenging to treat. Current interventions include focal laser or intravitreal injections. This article outlines a new treatment protocol based on the theory that peripheral ischemia is the precursor to angiogenesis, which will ultimately gather its momentum at the fovea. Extreme peripheral light laser panretinal photocoagulation (PRP) back to the equator reduces excessive production of the vascular endothelial growth factor (VEGF) in the eye. This decreases VEGF-induced DME and provides long-term protection against the development of neovascularization. Initial exacerbation of DME often accompanies PRP. Therefore, injections of anti-VEGF agents (with or without dexamethasone implants) initially can forestall worsening of DME and prevent loss of vision. However, on the other hand, applying peripheral PRP and intraocular injections can induce posterior vitreous detachment (PVD). This could help release vitreomacular adhesions (VMA) and vitreomacular traction (VMT), thereby decreasing DME severity and improving the response to intravitreal injections. In the current approach, peripheral retinal photocoagulation should stop the drive for VEGF release; moreover, laser ablation should produce secondary, accidental, and beneficial PVD. This approach precludes focal laser therapy and paves the path for prolonged intervals between anti-VEGF therapy. PMID:27800500

  5. Updates on the Clinical Trials in Diabetic Macular Edema

    PubMed Central

    Demirel, Sibel; Argo, Colby; Agarwal, Aniruddha; Parriott, Jacob; Sepah, Yasir Jamal; Do, Diana V.; Nguyen, Quan Dong

    2016-01-01

    In this era of evidence-based medicine, significant progress has been made in the field of pharmacotherapeutics for the management of diabetic macular edema (DME). A. number of landmark clinical trials have provided strong evidence of the safety and efficacy of agents such as anti-vascular endothelial growth factors for the treatment of DME. Decades of clinical research, ranging from the early treatment of diabetic retinopathy study to the present-day randomized clinical trials (RCTs) testing novel agents, have shifted the goal of therapy from preventing vision loss to ensuring a maximum visual gain. Systematic study designs have provided robust data with an attempt to optimize the treatment regimens including the choice of the agent and timing of therapy. However, due to a number of challenges in the management of DME with approved agents, further studies are needed. For the purpose of this review, an extensive database search in English language was performed to identify prospective, RCTs testing pharmacological agents for DME. In order to acquaint the reader with the most relevant data from these clinical trials, this review focuses on pharmacological agents that are currently approved or have widespread applications in the management of DME. An update on clinical trials presently underway for DME has also been provided. PMID:26957834

  6. Eye Conditions in Older Adults: Age-Related Macular Degeneration.

    PubMed

    Iroku-Malize, Tochi; Kirsch, Scott

    2016-06-01

    Age-related macular degeneration (AMD) causes a progressive loss of photoreceptors in the macula. It is the most common cause of legal blindness in the United States, and some form of AMD is thought to affect more than 9 million individuals. Risk factors include older age, smoking, dyslipidemia, obesity, white race, female sex, and a family history of AMD. There are two types of advanced AMD: nonexudative (dry or geographic atrophy) and exudative (wet or neovascular). Both cause progressive central vision loss with intact peripheral vision. Nonexudative AMD accounts for 80% to 90% of all advanced cases, and more than 90% of patients with severe vision loss have exudative AMD. On ophthalmoscopic examination, early findings include drusen (ie, yellow deposits in the retina). Prominent choroidal vessels, subretinal edema, and/or hemorrhage are seen in wet AMD. Regular eye examinations, visual field testing, fluorescein angiography, and optical coherence tomography are used for diagnosis and to guide management. There is no specific therapy for dry AMD, but antioxidant supplementation may be helpful. Intravitreal injection of a vascular endothelial growth factor inhibitor is the treatment of choice for wet AMD. Optical aids and devices can help to maximize function for patients with AMD.

  7. Macular pigment and its contribution to visual performance and experience

    PubMed Central

    Loughman, James; Davison, Peter A.; Nolan, John M.; Akkali, Mukunda C.; Beatty, Stephen

    2010-01-01

    There is now a consensus, based on histological, biochemical and spectral absorption data, that the yellow colour observed at the macula lutea is a consequence of the selective accumulation of dietary xanthophylls in the central retina of the living eye. Scientific research continues to explore the function(s) of MP in the human retina, with two main hypotheses premised on its putative capacity to (1) protect the retina from (photo)-oxidative damage by means of its optical filtration and/or antioxidant properties, the so-called protective hypothesis and (2) influence the quality of visual performance by means of selective short wavelength light absorption prior to photoreceptor light capture, thereby attenuating the effects of chromatic aberration and light scatter, the so-called acuity and visibility hypotheses. The current epidemic of age-related macular degeneration has directed researchers to investigate the protective hypothesis of MP, while there has been a conspicuous lack of work designed to investigate the role of MP in visual performance. The aim of this review is to present and critically appraise the current literature germane to the contribution of MP, if any, to visual performance and experience.

  8. Mechanism of Inflammation in Age-Related Macular Degeneration

    PubMed Central

    Parmeggiani, Francesco; Romano, Mario R.; Costagliola, Ciro; Semeraro, Francesco; Incorvaia, Carlo; D'Angelo, Sergio; Perri, Paolo; De Palma, Paolo; De Nadai, Katia; Sebastiani, Adolfo

    2012-01-01

    Age-related macular degeneration (AMD) is a multifactorial disease that represents the most common cause of irreversible visual impairment among people over the age of 50 in Europe, the United States, and Australia, accounting for up to 50% of all cases of central blindness. Risk factors of AMD are heterogeneous, mainly including increasing age and different genetic predispositions, together with several environmental/epigenetic factors, that is, cigarette smoking, dietary habits, and phototoxic exposure. In the aging retina, free radicals and oxidized lipoproteins are considered to be major causes of tissue stress resulting in local triggers for parainflammation, a chronic status which contributes to initiation and/or progression of many human neurodegenerative diseases such as AMD. Experimental and clinical evidences strongly indicate the pathogenetic role of immunologic processes in AMD occurrence, consisting of production of inflammatory related molecules, recruitment of macrophages, complement activation, microglial activation and accumulation within those structures that compose an essential area of the retina known as macula lutea. This paper reviews some attractive aspects of the literature about the mechanisms of inflammation in AMD, especially focusing on those findings or arguments more directly translatable to improve the clinical management of patients with AMD and to prevent the severe vision loss caused by this disease. PMID:23209345

  9. Hospitalized cardiovascular events in patients with diabetic macular edema

    PubMed Central

    2012-01-01

    Background Microvascular and macrovascular complications in diabetes stem from chronic hyperglycemia and are thought to have overlapping pathophysiology. The aim of this study was to investigate the incidence rate of hospitalized myocardial infarctions (MI) and cerebrovascular accidents (CVA) in patients with diabetic macular edema (DME) compared with diabetic patients without retinal diseases. Methods This was a retrospective cohort study of a commercially insured population in an administrative claims database. DME subjects (n = 3519) and diabetes controls without retinal disease (n = 10557) were matched by age and gender. Healthcare claims were analyzed for the study period from 1 January 2002 to 31 December 2005. Incidence and adjusted rate ratios of hospitalized MI and CVA events were then calculated. Results The adjusted rate ratio for MI was 2.50 (95% CI: 1.83-3.41, p < 0.001) for DME versus diabetes controls. Predictors of MI events were heart disease, history of acute MI, and prior use of antiplatelet or anticoagulant drugs. The adjusted rate ratio for CVA was 1.98 (95% CI: 1.39-2.83, p < 0.001) for DME versus diabetes controls. Predictors of CVA events were cardiac arrhythmia, Charlson comorbidity scores, history of CVA, hyperlipidemia, and other cerebrovascular diseases. Conclusion Event rates of MI or CVA were higher in patients with DME than in diabetes controls. This study is one of few with sufficient sample size to accurately estimate the relationship between DME and cardiovascular outcomes. PMID:22646811

  10. Promising new treatments for neovascular age-related macular degeneration.

    PubMed

    Michels, Stephan; Schmidt-Erfurth, Ursula; Rosenfeld, Philip J

    2006-07-01

    Angiogenesis, the growth of new blood vessels from existing blood vessels, is responsible for vision loss in a variety of ophthalmic diseases. In neovascular age-related macular degeneration (AMD), the leading cause for legal blindness in many industrialised countries, abnormal blood vessels grow in the macula and cause blindness. There are a number of factors important in the angiogenic cascade but VEGF-A has been implicated in recent years as the major factor responsible for neovascular and exudative diseases of the eye. Numerous antiangiogenic drugs are in development but anti-VEGF drugs have shown great promise in treating neovascular AMD and other ocular diseases, and many of these drugs have been adopted from oncology where antiangiogenic therapy is gaining wide acceptance. For the first time in neovascular AMD, anti-VEGF drugs have brought the hope of vision improvement to a significant proportion of patients. This review provides an overview on angiogenic mechanisms, potential antiangiogenic treatment strategies and different antiangiogenic drugs with special focus on neovascular AMD. PMID:16787141

  11. Age-related macular degeneration: experimental and emerging treatments

    PubMed Central

    Hubschman, Jean Pierre; Reddy, Shantan; Schwartz, Steven D

    2009-01-01

    Purpose: This essay reviews the experimental treatments and new imaging modalities that are currently being explored by investigators to help treat patients with age-related macular degeneration (AMD). Design: Interpretative essay. Methods: Literature review and interpretation. Results: Experimental treatments to preserve vision in patients with exudative AMD include blocking vascular endothelial growth factor (VEGF), binding VEGF, and modulating the VEGF receptors. Investigators are also attempting to block signal transduction with receptor tyrosine kinase inhibitors. Experimental treatments for non-exudative AMD include agents that target inflammation, oxidative stress, and implement immune-modulation. The effectiveness of these newer pharmacologic agents has the potential to grow exponentially when used in combination with new and improved imaging modalities that can help identify disease earlier and follow treatment response more precisely. Conclusion: With a better understanding, at the genetic and molecular level, of AMD and the development of superior imaging modalities, investigators are able to offer treatment options that may offer unprecedented visual gains while reducing the need for repetitive treatments. PMID:19668561

  12. Black holes and beyond

    NASA Astrophysics Data System (ADS)

    Mathur, Samir D.

    2012-11-01

    The black hole information paradox forces us into a strange situation: we must find a way to break the semiclassical approximation in a domain where no quantum gravity effects would normally be expected. Traditional quantizations of gravity do not exhibit any such breakdown, and this forces us into a difficult corner: either we must give up quantum mechanics or we must accept the existence of troublesome 'remnants'. In string theory, however, the fundamental quanta are extended objects, and it turns out that the bound states of such objects acquire a size that grows with the number of quanta in the bound state. The interior of the black hole gets completely altered to a 'fuzzball' structure, and information is able to escape in radiation from the hole. The semiclassical approximation can break at macroscopic scales due to the large entropy of the hole: the measure in the path integral competes with the classical action, instead of giving a subleading correction. Putting this picture of black hole microstates together with ideas about entangled states leads to a natural set of conjectures on many long-standing questions in gravity: the significance of Rindler and de Sitter entropies, the notion of black hole complementarity, and the fate of an observer falling into a black hole.

  13. ULTRAMASSIVE BLACK HOLE COALESCENCE

    SciTech Connect

    Khan, Fazeel Mahmood; Holley-Bockelmann, Kelly; Berczik, Peter E-mail: k.holley@vanderbilt.edu

    2015-01-10

    Although supermassive black holes (SMBHs) correlate well with their host galaxies, there is an emerging view that outliers exist. Henize 2-10, NGC 4889, and NGC 1277 are examples of SMBHs at least an order of magnitude more massive than their host galaxy suggests. The dynamical effects of such ultramassive central black holes is unclear. Here, we perform direct N-body simulations of mergers of galactic nuclei where one black hole is ultramassive to study the evolution of the remnant and the black hole dynamics in this extreme regime. We find that the merger remnant is axisymmetric near the center, while near the large SMBH influence radius, the galaxy is triaxial. The SMBH separation shrinks rapidly due to dynamical friction, and quickly forms a binary black hole; if we scale our model to the most massive estimate for the NGC 1277 black hole, for example, the timescale for the SMBH separation to shrink from nearly a kiloparsec to less than a parsec is roughly 10 Myr. By the time the SMBHs form a hard binary, gravitational wave emission dominates, and the black holes coalesce in a mere few Myr. Curiously, these extremely massive binaries appear to nearly bypass the three-body scattering evolutionary phase. Our study suggests that in this extreme case, SMBH coalescence is governed by dynamical friction followed nearly directly by gravitational wave emission, resulting in a rapid and efficient SMBH coalescence timescale. We discuss the implications for gravitational wave event rates and hypervelocity star production.

  14. Antarctic Ozone Hole, 2000

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Each spring the ozone layer over Antarctica nearly disappears, forming a 'hole' over the entire continent. The hole is created by the interaction of some man-made chemicals-freon, for example-with Antarctica's unique weather patterns and extremely cold temperatures. Ozone in the stratosphere absorbs ultraviolet radiation from the sun, thereby protecting living things. Since the ozone hole was discovered many of the chemicals that destroy ozone have been banned, but they will remain in the atmosphere for decades. In 2000, the ozone hole grew quicker than usual and exceptionally large. By the first week in September the hole was the largest ever-11.4 million square miles. The top image shows the average total column ozone values over Antarctica for September 2000. (Total column ozone is the amount of ozone from the ground to the top of the atmosphere. A relatively typical measurement of 300 Dobson Units is equivalent to a layer of ozone 0.12 inches thick on the Earth's surface. Levels below 220 Dobson Units are considered to be significant ozone depletion.) The record-breaking hole is likely the result of lower than average ozone levels during the Antarctic fall and winter, and exceptionally cold temperatures. In October, however (bottom image), the hole shrank dramatically, much more quickly than usual. By the end of October, the hole was only one-third of it's previous size. In a typical year, the ozone hole does not collapse until the end of November. NASA scientists were surprised by this early shrinking and speculate it is related to the region's weather. Global ozone levels are measured by the Total Ozone Mapping Spectrometer (TOMS). For more information about ozone, read the Earth Observatory's ozone fact sheet, view global ozone data and see these ozone images. Images by Greg Shirah, NASA GSFC Scientific Visualization Studio.

  15. Measuring Black Hole Spin

    NASA Astrophysics Data System (ADS)

    Garmire, Gordon

    1999-09-01

    WE PROPOSE TO CARRY OUT A SYSTEMATIC STUDY OF EMISSION AND ABSORPTION SPECTRAL FEATURES THAT ARE OFTEN SEEN IN X-RAY SPECTRA OF BLACK HOLE BINARIES. THE EXCELLENT SENSITIVITY AND ENERGY RESOLUTION OF THE ACIS/HETG COMBINATION WILL NOT ONLY HELP RESOLVE AMBIGUITIES IN INTERPRETING THESE FEATURES, BUT MAY ALLOW MODELLING OF THE EMISSION LINE PROFILES IN DETAIL. THE PROFILES MAY CONTAIN INFORMATION ON SUCH FUNDAMENTAL PROPERTIES AS THE SPIN OF BLACK HOLES. THEREFORE, THIS STUDY COULD LEAD TO A MEASUREMENT OF BLACK HOLE SPIN FOR SELECTED SOURCES. THE RESULT CAN THEN BE DIRECTLY COMPARED WITH THOSE FROM PREVIOUS STUDIES BASED ON INDEPENDENT METHODS.

  16. Strong topical steroid, NSAID, and carbonic anhydrase inhibitor cocktail for treatment of cystoid macular edema

    PubMed Central

    Asahi, Masumi G; Bobarnac Dogaru, Gabriela L; Onishi, Spencer M; Gallemore, Ron P

    2015-01-01

    Purpose To report the combination cocktail of strong steroid, non-steroidal anti-inflammatory drug (NSAID), and carbonic anhydrase inhibitor drops for treatment of cystoid macular edema. Methods This is a retrospective case series of patients with cystoid macular edema managed with a topical combination of strong steroid (difluprednate), NSAID, and carbonic anhydrase inhibitor drops. The patients were followed with optical coherence tomography and fluorescein angiography. Results In our six cases, resolution of the cystic edema with improvement in visual acuity was achieved with the use of a combination cocktail of drops. Leakage on fluorescein angiography and cystic edema on optical coherence tomography both responded to treatment with the topical cocktail of drops. Conclusion A topical cocktail of strong steroid, NSAID, and carbonic anhydrase inhibitor drops are effective for managing cystoid macular edema. Further studies comparing this combination with more invasive treatments should be undertaken to determine the efficacy of this cocktail over other treatment options. PMID:26664246

  17. Eye movements and reading in macular disease: further support for the shrinking perceptual span hypothesis.

    PubMed

    Crossland, Michael D; Rubin, Gary S

    2006-02-01

    Reduced perceptual span is one factor which limits reading speed in patients with macular disease. This study measured the perceptual span and the number of saccades to locate a target in 18 patients with macular disease and seven control subjects on two occasions separated by up to 12 months. Perceptual span changed by up to two letters. Changes in perceptual span were significantly related to changes in reading speed (r2 = 0.43, p < 0.005), and were independent of changes in the number of saccades used to observe a target (r2 = 0.003, p = 0.62). These findings have important implications for the development of training programmes for patients with macular disease.

  18. Introducing the Black Hole

    ERIC Educational Resources Information Center

    Ruffini, Remo; Wheeler, John A.

    1971-01-01

    discusses the cosmology theory of a black hole, a region where an object loses its identity, but mass, charge, and momentum are conserved. Include are three possible formation processes, theorized properties, and three way they might eventually be detected. (DS)

  19. Illuminating black holes

    NASA Astrophysics Data System (ADS)

    Barr, Ian A.; Bull, Anne; O’Brien, Eileen; Drillsma-Milgrom, Katy A.; Milgrom, Lionel R.

    2016-07-01

    Two-dimensional shadows formed by illuminating vortices are shown to be visually analogous to the gravitational action of black holes on light and surrounding matter. They could be useful teaching aids demonstrating some of the consequences of general relativity.

  20. Astrophysics: Monster black holes

    NASA Astrophysics Data System (ADS)

    Cappellari, Michele

    2011-12-01

    A combination of ground-based and spacecraft observations has uncovered two black holes of 10 billion solar masses in the nearby Universe. The finding sheds light on how these cosmic monsters co-evolve with galaxies.

  1. Bilateral macular hemorrhage due to megaloblastic anemia: A rare case report

    PubMed Central

    Vaggu, Sree Kumar; Bhogadi, Preethi

    2016-01-01

    We report a case of a 17-year-old female patient who presented with sudden, painless, nonprogressive diminished vision in both eyes (best corrected visual acuity in right eye - 6/60 and left eye - 6/36). An ophthalmological evaluation revealed bilateral pale tarsal conjunctiva and bilateral macular hemorrhage. Hematological evaluation revealed the presence of megalocytic anemia (with hemoglobin - 4.9 g%). General examination showed severe pallor. On systemic examination, no abnormality was detected, confirmed by ultrasonography abdomen. Other causes. This case documents the rare occurrence of bilateral subinternal limiting membrane macular hemorrhage with megaloblastic anemia without thrombocytopenia and other retinal features of anemic retinopathy. PMID:27050355

  2. Macular SD-OCT Outcome Measures: Comparison of Local Structure-Function Relationships and Dynamic Range

    PubMed Central

    Miraftabi, Arezoo; Amini, Navid; Morales, Esteban; Henry, Sharon; Yu, Fei; Afifi, Abdolmonem; Coleman, Anne L.; Caprioli, Joseph; Nouri-Mahdavi, Kouros

    2016-01-01

    Purpose We tested the hypothesis that the macular ganglion cell layer (GCL) thickness demonstrates a stronger structure-function (SF) relationship and extends the useful range of macular measurements compared with combined macular inner layer or full thickness. Methods Ninety-eight glaucomatous eyes and eight normal eyes with macular spectral domain optical coherence tomography (SD-OCT) volume scans and 10-2 visual fields were enrolled. Inner plexiform layer (IPL), GCL, macular retinal nerve fiber layer (mRNFL), ganglion cell-inner plexiform layer (GCIPL), ganglion cell complex (GCC), and full thickness (FT) measurements were calculated for 8 × 8 arrays of 3° superpixels. Main outcome measures were local structure-function relationships between macular superpixels and corresponding sensitivities on 10-2 fields after adjusting for ganglion cell displacement, dynamic range of measurements, and the change point (total deviation value where macular parameters reached measurement floor). Results Median (interquartile range [IQR]) mean deviation was −7.2 (−11.6 to −3.2) dB in glaucoma eyes. Strength of SF relationships was highest for GCIPL, GCL, GCC, and IPL (ρ = 0.635, 0.627, 0.621, and 0.577, respectively; P ≤ 0.046 for comparisons against GCIPL). Highest SF correlations coincided with the peak of GCL thickness, where the dynamic range was widest for FT (81.1 μm), followed by GCC (65.7 μm), GCIPL (54.9 μm), GCL (35.2 μm), mRNFL (27.5 μm), and IPL (20.9 μm). Change points were similar for all macular parameters (−7.8 to −8.9 dB). Conclusions GCIPL, GCL, and GCC demonstrated comparable SF relationships while FT, GCC, and GCIPL had the widest dynamic range. Measurement of GCL did not extend the range of useful structural measurements. Measuring GCL does not provide any advantage for detection of progression with current SD-OCT technology. PMID:27623336

  3. Role of aflibercept for macular edema following branch retinal vein occlusion: comparison of clinical trials.

    PubMed

    Oellers, Patrick; Grewal, Dilraj S; Fekrat, Sharon

    2016-01-01

    For years, the standard of care for branch-retinal-vein-occlusion-associated macular edema was initial observation followed by grid-pattern laser photocoagulation for persistent edema. Newer pharmacologic options have revolutionized the management of branch-retinal-vein-occlusion-associated macular edema, and the visual outcomes of these eyes are better than ever. However, a variety of available treatment options including intravitreal corticosteroids and intravitreal anti-vascular endothelial growth factor agents have established novel challenges with regard to appropriate drug selection. This review summarizes the available clinical studies with special emphasis on the comparison of intravitreal aflibercept with ranibizumab, bevacizumab, and steroid agents. PMID:27022238

  4. Helical superconducting black holes.

    PubMed

    Donos, Aristomenis; Gauntlett, Jerome P

    2012-05-25

    We construct novel static, asymptotically five-dimensional anti-de Sitter black hole solutions with Bianchi type-VII(0) symmetry that are holographically dual to superconducting phases in four spacetime dimensions with a helical p-wave order. We calculate the precise temperature dependence of the pitch of the helical order. At zero temperature the black holes have a vanishing entropy and approach domain wall solutions that reveal homogenous, nonisotropic dual ground states with an emergent scaling symmetry.

  5. Orthotropic hole element

    NASA Technical Reports Server (NTRS)

    Markham, J. W.; Smith, C. V.

    1983-01-01

    A finite element was developed to adequately represent the state of stress in the region around a circular hole in orthotropic material experiencing reasonably general loading. This has been achieved through a complementary virtual work formulation of the stiffness and stress matrices for a square element with a center circular hole. The element has been incorporated into COSMIC/NASTRAN as a dummy element. Sample problems have been solved and these results are presented.

  6. Black holes and beyond

    SciTech Connect

    Mathur, Samir D.

    2012-11-15

    The black hole information paradox forces us into a strange situation: we must find a way to break the semiclassical approximation in a domain where no quantum gravity effects would normally be expected. Traditional quantizations of gravity do not exhibit any such breakdown, and this forces us into a difficult corner: either we must give up quantum mechanics or we must accept the existence of troublesome 'remnants'. In string theory, however, the fundamental quanta are extended objects, and it turns out that the bound states of such objects acquire a size that grows with the number of quanta in the bound state. The interior of the black hole gets completely altered to a 'fuzzball' structure, and information is able to escape in radiation from the hole. The semiclassical approximation can break at macroscopic scales due to the large entropy of the hole: the measure in the path integral competes with the classical action, instead of giving a subleading correction. Putting this picture of black hole microstates together with ideas about entangled states leads to a natural set of conjectures on many long-standing questions in gravity: the significance of Rindler and de Sitter entropies, the notion of black hole complementarity, and the fate of an observer falling into a black hole. - Highlights: Black-Right-Pointing-Pointer The information paradox is a serious problem. Black-Right-Pointing-Pointer To solve it we need to find 'hair' on black holes. Black-Right-Pointing-Pointer In string theory we find 'hair' by the fuzzball construction. Black-Right-Pointing-Pointer Fuzzballs help to resolve many other issues in gravity.

  7. Charged Galileon black holes

    SciTech Connect

    Babichev, Eugeny; Charmousis, Christos; Hassaine, Mokhtar E-mail: christos.charmousis@th.u-psud.fr

    2015-05-01

    We consider an Abelian gauge field coupled to a particular truncation of Horndeski theory. The Galileon field has translation symmetry and couples non minimally both to the metric and the gauge field. When the gauge-scalar coupling is zero the gauge field reduces to a standard Maxwell field. By taking into account the symmetries of the action, we construct charged black hole solutions. Allowing the scalar field to softly break symmetries of spacetime we construct black holes where the scalar field is regular on the black hole event horizon. Some of these solutions can be interpreted as the equivalent of Reissner-Nordstrom black holes of scalar tensor theories with a non trivial scalar field. A self tuning black hole solution found previously is extended to the presence of dyonic charge without affecting whatsoever the self tuning of a large positive cosmological constant. Finally, for a general shift invariant scalar tensor theory we demonstrate that the scalar field Ansatz and method we employ are mathematically compatible with the field equations. This opens up the possibility for novel searches of hairy black holes in a far more general setting of Horndeski theory.

  8. Braneworld Black Holes

    NASA Astrophysics Data System (ADS)

    Whisker, Richard

    2008-10-01

    In this thesis we investigate black holes in the Randall-Sundrum braneworld scenario. We begin with an overview of extra-dimensional physics, from the original proposal of Kaluza and Klein up to the modern braneworld picture of extra dimensions. A detailed description of braneworld gravity is given, with particular emphasis on its compatibility with experimental tests of gravity. We then move on to a discussion of static, spherically symmetric braneworld black hole solutions. Assuming an equation of state for the ``Weyl term'', which encodes the effects of the extra dimension, we are able to classify the general behaviour of these solutions. We then use the strong field limit approach to investigate the gravitational lensing properties of some candidate braneworld black hole solutions. It is found that braneworld black holes could have significantly different observational signatures to the Schwarzschild black hole of standard general relativity. Rotating braneworld black hole solutions are also discussed, and we attempt to generate rotating solutions from known static solutions using the Newman-Janis complexification ``trick''.

  9. Searching for Black Holes

    NASA Technical Reports Server (NTRS)

    Garcia, M.

    1998-01-01

    Our UV/VIS work concentrates on black hole X-ray nova. These objects consist of two stars in close orbit, one of which we believe is a black hole - our goal is to SHOW that one is a black hole. In order to reach this goal we carry out observations in the Optical, UV, IR and X-ray bands, and compare the observations to theoretical models. In the past year, our UV/VIS grant has provided partial support (mainly travel funds and page charges) for work we have done on X-ray nova containing black holes and neutron stars. We have been very successful in obtaining telescope time to support our project - we have completed approximately a dozen separate observing runs averaging 3 days each, using the MMT (5M), Lick 3M, KPNO 2.1M, CTIO 4M, CTIO 1.5M, and the SAO/WO 1.2M telescopes. These observations have allowed the identification of one new black hole (Nova Oph 1977), and allowed the mass of another to be measured (GS2000+25). Perhaps our most exciting new result is the evidence we have gathered for the existence of 'event horizons' in black hole X-ray nova.

  10. Age-Related Macular Degeneration: Genetics and Biology.

    PubMed

    Kumaramanickavel, Govindasamy

    2016-01-01

    Age-related macular degeneration (AMD), widely prevalent across the globe, is a major stakeholder among adult visual morbidity and blindness, not only in the Western world but also in Asia. Several risk factors have been identified, including critical genetic factors, which were never imagined 2 decades ago. The etiopathogenesis is emerging to demonstrate that immune and complement-related inflammation pathway members chronically exposed to environmental insults could justifiably influence disease morbidity and treatment outcomes. Approximately half a dozen physiological and biochemical cascades are disrupted in the AMD disease genesis, eventually leading to the distortion and disruption of the subretinal space, subretinal pigment epithelium, and Bruch membrane, thus setting off chaos and disorder for signs and symptoms to manifest. Approximately 3 dozen genetic factors have so far been identified, including the recent ones, through powerful genomic technologies and large robust sample sizes. The noteworthy genetic variants (common and rare) are complement factor H, complement factor H-related genes 1 to 5, C3, C9, ARMS2/HTRA1, vascular endothelial growth factor A, vascular endothelial growth factor receptor 2/KDR, and rare variants (show causal link) such as TIMP3, fibrillin, COL4A3, MMP19, and MMP9. Despite the enormous amount of scientific information generated over the years, diagnostic genetic or biomarker tests are still not available for clinicians to understand the natural course of the disease and its management in a patient. However, further research in the field should reduce this gap not only by aiding the clinician but also through the possibilities of clinical intervention with complement pathway-related inhibitors entering preclinical and clinical trials in the near future. PMID:27488064

  11. Gene Therapy for Age-Related Macular Degeneration.

    PubMed

    Constable, Ian Jeffery; Blumenkranz, Mark Scott; Schwartz, Steven D; Barone, Sam; Lai, Chooi-May; Rakoczy, Elizabeth Piroska

    2016-01-01

    The purpose of this article was to evaluate safety and signals of efficacy of gene therapy with subretinal rAAV.sFlt-1 for wet age-related macular degeneration (wet AMD). A phase 1 dose-escalating single-center controlled unmasked human clinical trial was followed up by extension of the protocol to a phase 2A single-center trial. rAAV.sFlt-1 vector was used to deliver a naturally occurring anti-vascular endothelial growth factor agent, sFlt-1, into the subretinal space. In phase 1, step 1 randomized 3 subjects to low-dose rAAV.sFlt-1 (1 × 10 vector genomes) and 1 subject to the control arm; step 2 randomized an additional 3 subjects to treatment with high-dose rAAV.sFlt-1 (1 × 10 vector genomes) and 1 subject to the control arm. Follow-up studies demonstrated that rAAV.sFlt-1 was well tolerated with a favorable safety profile in these elderly subjects with wet AMD. Subretinal injection was highly reproducible, and no drug-related adverse events were reported. Procedure-related adverse events were mild and self-resolving. Two phakic patients developed cataract and underwent cataract surgery. Four of the 6 patients responded better than the small control group in this study and historical controls in terms of maintaining vision and a relatively dry retina with zero ranibizumab retreatments per annum. Two patients required 1 ranibizumab injection over the 52-week follow-up period. rAAV.sFlt-1 gene therapy may prove to be a potential adjunct or alternative to conventional intravitreal injection for patients with wet AMD by providing extended delivery of a naturally occurring antiangiogenic protein. PMID:27488071

  12. Progressive macular hypomelanosis among Egyptian patients: a clinicopathological study

    PubMed Central

    Selim, Mohamed Khaled; Ahmed, El-Shahat Farag; Abdelgawad, Mamdouh Morsy; El-Kamel, Mohammed Fawzy

    2011-01-01

    Background: Progressive macular hypomelanosis (PMH) is a disease of unclear etiology. Propionbacterium acnes (P. acnes) was claimed to be an etiological factor. Objectives: The purpose of this study was to document the clinicopathological features of PMH in Egyptian patients and to evaluate the therapeutic outcome. Methods: Patients with clinical features of PMH were recruited. Wood’s lamp examination, skin scrapings for fungi, and skin biopsy specimens were obtained. Biopsies were stained with hematoxylin and eosin, PAS, Fontana-Masson, and S100 protein. Patients received either narrow-band UVB (nbUVB) or nbUVB plus daily topical clindamycin 1% and benzoyl peroxide gel 5% (bcUVB). The period of active treatment was 14 weeks followed by a follow-up period of 24 weeks. Results: Twenty-nine patients were included. Microscopic evaluation of skin biopsy specimens showed no significant differences between lesional and normal skin. Fontana-Masson stained sections showed overall reduction of melanin granules in the basal layer of lesional skin only and S100 staining did not detect significant differences in the number of melanocytes in lesional and normal skin. Nearly complete repigmentation was reported in 10 patients treated with bcUVB compared to 9 patients treated with nbUVb with no significant differences between both groups after 14 weeks. Only 2 patients in each group retained the pigmentation and the remaining patients returned to the baseline color before treatment. Conclusions: This study documented the clinicopathological features of PMH among Egyptians. No permanently effective treatment is available. Further studies are needed to prove or disprove the pathogenic role of P. acnes in PMH. PMID:24396712

  13. [NUTRITIONAL COMPONENTS AND MACULAR DEGENERATION AGE-RELATED].

    PubMed

    García-Montalvo, Iván Antonio; Matías-Pérez, Diana

    2015-04-28

    Objetivo: componentes nutricionales como los antioxidantes pueden modificar el riesgo de padecer Degeneración Macular Relacionada con la Edad (DMRE). Este es un artículo de revisión sistemática de estudios publicados relacionados con la modificación del estilo de vida, la nutrición y la ingesta de vitaminas para prevenir o retrasar la aparición o progresión de la DMRE. Resultados: el análisis de los resultados de investigación consultados pone de manifiesto que la DMRE es una de las causas de ceguera más frecuentes en sujetos mayores de 55 años. La DMRE se caracteriza por disminución de la visión, metamorfosias, macropsias, micropsias y escotoma central. Es una enfermedad que debe ser diagnosticada a tiempo, ya que puede conducir a la ceguera irreversible. Entre los componentes de la dieta que en numerosos estudios epidemiológicos han mostrado una asociación inversa con la DMRE y que se revisan en este trabajo se encuentran: vitaminas (E y C), minerales (ej. zinc, selenio, manganeso y cobre) y carotenoides. Conclusiones: existe una evidencia importante de que puede aplicarse un soporte nutricional a pacientes con DMRE. Esto requiere de la determinación de los beneficios nutricionales de estos nutrientes (vitaminas, minerales y carotenoides), o bien de alimentos nutracéuticos en pro de la salud de este grupo de enfermos.

  14. Genetic risk factors and age-related macular degeneration (AMD)

    PubMed Central

    Mousavi, Maryam; Armstrong, Richard A.

    2013-01-01

    Age related macular degeneration (AMD) is the leading cause of blindness in individuals older than 65 years of age. It is a multifactorial disorder and identification of risk factors enables individuals to make lifestyle choices that may reduce the risk of disease. Collaboration between geneticists, ophthalmologists, and optometrists suggests that genetic risk factors play a more significant role in AMD than previously thought. The most important genes are associated with immune system modulation and the complement system, e.g., complement factor H (CFH), factor B (CFB), factor C3, and serpin peptidase inhibitor (SERPING1). Genes associated with membrane transport, e.g., ATP-binding cassette protein (ABCR) and voltage-dependent calcium channel gamma 3 (CACNG3), the vascular system, e.g., fibroblast growth factor 2 (FGF2), fibulin-5, lysyl oxidase-like gene (LOXL1) and selectin-P (SELP), and with lipid metabolism, e.g., apolipoprotein E (APOE) and hepatic lipase (LIPC) have also been implicated. In addition, several other genes exhibit some statistical association with AMD, e.g., age-related maculopathy susceptibility protein 2 (ARMS2) and DNA excision repair protein gene (ERCC6) but more research is needed to establish their significance. Modifiable risk factors for AMD should be discussed with patients whose lifestyle and/or family history place them in an increased risk category. Furthermore, calculation of AMD risk using current models should be recommended as a tool for patient education. It is likely that AMD management in future will be increasingly influenced by assessment of genetic risk as such screening methods become more widely available.

  15. Vitrectomy for center-involved diabetic macular edema

    PubMed Central

    Browning, David J; Lee, Chong; Stewart, Michael W; Landers, Maurice B

    2016-01-01

    Purpose To determine the effect of vitrectomy for center-involved diabetic macular edema (CI-DME). Methods This was a retrospective study of 53 eyes of 45 patients who had vitrectomy for CI-DME and were followed up for at least 12 months. Charts were reviewed for visual acuity (VA), central subfield mean thickness measured by optical coherence tomography, presurgical and postsurgical interventions for CI-DME, and number of office visits in the first 12 months after surgery. Preoperative spectral domain optical coherence tomography was performed on 38 patients, and they were graded for ellipsoid zone (EZ) intactness by three independent graders with assessment of agreement between graders using intraclass correlation coefficients and Bland–Altman analysis. Results The median VA improved from 20/100 (interquartile range [IQR], 20/63–20/200) at baseline to 20/63 (IQR, 20/32–20/125) at 12 months. The median central subfield mean thickness improved from 505 μm (IQR, 389–597 μm) at baseline to 279 μm (IQR, 246–339 μm) at 12 months. Intergrader agreement for EZ intactness was moderate (intraclass correlation coefficients 0.4294–0.6356). There was no relationship between preoperative intactness of the EZ and the 12-month change in VA. Conclusion Vitrectomy consistently thins the macula in CI-DME and, on average, leads to clinically significant improvement in VA comparable in size to that reported with serial intravitreal anti-vascular endothelial growth factor injections. A large, comparative, prospective, randomized clinical trial of these two treatments is needed to determine which is more effective and cost-effective. PMID:27175056

  16. Glycolysis in Patients with Age-Related Macular Degeneration

    PubMed Central

    Yokosako, Kanako; Mimura, Tatsuya; Funatsu, Hideharu; Noma, Hidetaka; Goto, Mari; Kamei, Yuko; Kondo, Aki; Matsubara, Masao

    2014-01-01

    Purpose: Retinal adenosine triphosphate is mainly produced via glycolysis, so inhibition of glycolysis may promote the onset and progression of age-related macular degeneration (AMD). When glycolysis is inhibited, pyruvate is metabolized by lactic acid fermentation instead of entering the mitochondrial tricarboxylic acid (TCA) cycle. We measured urinary pyruvate and lactate levels in patients with AMD. Methods: Eight patients with typical AMD (tAMD group) and 9 patients with polypoidal choroidal vasculopathy (PCV group) were enrolled. Urinary levels of pyruvate, lactate, α-hydroxybutyrate, and β-hydroxybutyrate were measured in all patients. Results: The mean urinary levels of pyruvate and lactate were 8.0 ± 2.8 and 7.5 ± 8.3 μg/mg creatinine (reference values: 0.5-6.6 and 0.0-1.6), respectively, with the mean increase over the reference value being 83.6 ± 51.1% and 426.5 ± 527.8%, respectively. In 12 patients (70.6%), the lactate/pyruvate ratio was above the reference range. Urinary levels of α-hydroxybutyrate and β-hydroxybutyrate were decreased by -31.9 ± 15.2% and -33.1 ± 17.5% compared with the mean reference values. There were no significant differences of any of these glycolysis metabolites between the tAMD and PCV groups. Multivariate analysis revealed that none of the variables tested, including patient background factors (age, hypertension, diabetes, hyperlipidemia, cerebrovascular disease, alcohol, smoking, visual acuity, and AMD phenotype), were significantly associated with the lactate/pyruvate ratio. Conclusion: A high lactate/pyruvate ratio is a well-known marker of mitochondrial impairment, and it indicates poor oxidative function in AMD. Our results suggest that increased lactate levels may be implicated in the pathogenesis of AMD. PMID:25191529

  17. The Macular Degeneration and Aging Study: Design and Research Protocol of a Randomized Trial for a Psychosocial Intervention with Macular Degeneration Patients

    PubMed Central

    Sörensen, Silvia; White, Katherine; Mak, Wingyun; Zanibbi, Katherine; Tang, Wan; O’Hearn, Amanda; Hegel, Mark T.

    2015-01-01

    Age-related Macular Degeneration (AMD) is the leading cause of irreversible and predictable blindness among older adults and creates serious physical and mental health consequences for this population. Visual impairment is associated with negative future outlook and depression and has serious consequences for older adults’ quality of life and, by way of depression, on long-term survival. Psychosocial interventions have the potential to alleviate and prevent depression symptoms among older AMD patients. We describe the protocol of the Macular Degeneration and Aging Study, a randomized clinical trial of a psychosocial Preventive Problem-Solving Intervention. The intervention is aimed at enhancing well-being and future planning among older adults with macular degeneration by increasing preparation for future care. Adequate randomization and therapeutic fidelity were achieved. Current retention rates were acceptable, given the vulnerability of the population. Acceptability (adherence and satisfaction) is high. Given the high public health significance and impact on quality of life among older adults with vision loss, this protocol contributes a valid test of a promising intervention for maintaining mental and physical health in this population. PMID:25812482

  18. Effect of Supplemental Lutein and Zeaxanthin on Serum, Macular Pigmentation, and Visual Performance in Patients with Early Age-Related Macular Degeneration

    PubMed Central

    Huang, Yang-Mu; Dou, Hong-Liang; Huang, Fei-Fei; Xu, Xian-Rong; Zou, Zhi-Yong

    2015-01-01

    Purpose. To compare the 2-year effect of multiple doses of lutein/zeaxanthin on serum, macular pigmentation, and visual performance on patients with early age-related macular degeneration (AMD). Methods. In this randomized, double-blinded, and placebo-controlled trial, 112 early AMD patients randomly received either 10 mg lutein, 20 mg lutein, a combination of lutein (10 mg) and zeaxanthin (10 mg), or placebo daily for 2 years. Serum concentration of lutein/zeaxanthin, macular pigment optical density (MPOD), visual functions including best-spectacle corrected visual acuity (BCVA), contrast sensitivity (CS), flash recovery time (FRT), and vision-related quality of life (VFQ25) was quantified. Results. Serum lutein concentration and MPOD significantly increased in all the active treatment groups. Supplementation with 20 mg lutein was the most effective in increasing MPOD and CS at 3 cycles/degree for the first 48 weeks. However, they both significantly increased to the same peak value following supplementation with either 10 mg or 20 mg lutein during the intervention. No statistical changes of BCVA or FRT were observed during the trial. Conclusions. Long-term lutein supplementation could increase serum lutein concentration, MPOD, and visual sensitivities of early AMD patients. 10 mg lutein daily might be an advisable long-term dosage for early AMD treatment. PMID:25815324

  19. Clinical effects and safety of treating diabetic macular edema with intravitreal injection of ranibizumab combined with retinal photocoagulation

    PubMed Central

    Yan, Panshi; Qian, Cheng; Wang, Wenzhan; Dong, Yi; Wan, Guangming; Chen, Yue

    2016-01-01

    Background This study was designed to examine the clinical effects of treating diabetic macular edema with an intravitreal injection of ranibizumab in combination with retinal photocoagulation. Methods Sixty-two cases (75 eyes) with confirmed severe proliferative diabetic retinopathy or proliferative diabetic retinopathy in combination with macular edema were randomly divided into the observation group (37 eyes were given an intravitreal injection of ranibizumab combined with retinal photocoagulation) and the control group (38 eyes received retinal photocoagulation only). Vision, fundus condition, central macular thickness, and the macular leakage area were recorded before and after treatment. Results The best-corrected visual acuity and macular leakage area were similar between the observation and control groups (P>0.05). The best-corrected visual acuity in the observation group was higher than that in the control group 3 and 6 months after treatment (P<0.05) and showed a rising tendency. The macular leakage area in the observation group was significantly lower than that in the control group 1 and 3 months after treatment (P<0.05). However, the macular leakage area was similar 6 months after treatment (P>0.05). The central macular thickness of the observation group was lower than that in the control group 1, 3, and 6 months after treatment (P<0.05). The laser energy used in the observation group was also smaller than that in the control group (P<0.05). The intraocular pressure was not significantly different between the groups (P<0.05). No patients in the two groups developed eye or systemic complications, such as glaucoma, cataract, or vitreous hemorrhage during treatment. Conclusion Intravitreal injection of ranibizumab combined with retinal photocoagulation was proven to be effective in treating diabetic macular edema as it improved vision and resulted in fewer complications. PMID:27103811

  20. Merging Black Holes

    NASA Technical Reports Server (NTRS)

    Centrella, John

    2009-01-01

    The final merger of two black holes is expected to be the strongest gravitational wave source for ground-based interferometers such as LIGO, VIRGO, and GEO600, as well as the space-based LISA. Observing these sources with gravitational wave detectors requires that we know the radiation waveforms they emit. And, when the black holes merge in the presence of gas and magnetic fields, various types of electromagnetic signals may also be produced. Since these mergers take place in regions of extreme gravity, we need to solve Einstein's equations of general relativity on a computer. For more than 30 years, scientists have tried to compute black hole mergers using the methods of numerical relativity. The resulting computer codes have been plagued by instabilities, causing them to crash well before the black holes in the binary could complete even a single orbit. Within the past few years, however, this situation has changed dramatically, with a series of remarkable breakthroughs. This talk will focus on new simulations that are revealing the dynamics and waveforms of binary black hole mergers, and their applications in gravitational wave detection, testing general relativity, and astrophysics.

  1. Ranibizumab in the treatment of patients with visual impairment due to diabetic macular edema

    PubMed Central

    Bandello, Francesco; De Benedetto, Umberto; Knutsson, Karl Anders; Parodi, Maurizio Battaglia; Cascavilla, Maria Lucia; Iacono, Pierluigi

    2011-01-01

    Diabetic macular edema is the major cause of visual acuity impairment in diabetic patients. The exact etiopathogenesis is unknown and, currently, grid/focal retinal laser photocoagulation represents the recommended treatment. It has been demonstrated that vascular endothelial growth factor (VEGF) plays a key role in the pathogenesis of diabetic macular edema by mediating vascular permeability and accumulation of intracellular and extracellular fluid, and thereby represents an appealing candidate as a therapeutic target for the treatment of diabetic macular edema. The advent of intravitreal anti-VEGF drugs has opened up a new era for the management of diabetic macular edema. At present, three anti-VEGF substances are available for routine clinical use, ie, pegaptanib, ranibizumab, and bevacizumab. The aim of this review is to summarize the evidence supporting the use of ranibizumab in clinical practice. Most of the studies analyzed in this review are prospective, controlled clinical trials that have focused on documenting the therapeutic effect of ranibizumab and its safety, providing encouraging results. PMID:21966206

  2. A systematic review on zinc for the prevention and treatment of age-related macular degeneration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Zinc is a potential candidate for the prevention and treatment of age-related macular degeneration (AMD) due to its high concentration in the retina and role as a cofactor for antioxidant enzymes. The objective of this work was to conduct a systematic review of studies that investigated dietary inta...

  3. Suspected macular degeneration in a captive Western lowland gorilla (Gorilla gorilla gorilla).

    PubMed

    Steinmetz, Andrea; Bernhard, Andreas; Sahr, Sabine; Oechtering, Gerhard

    2012-09-01

    The case of a 31-year-old captive female Western lowland gorilla (Gorilla gorilla gorilla) with decreased near vision but good distance vision is presented. Examination of the fundus revealed drusen-like bodies in the macula presumably because of an age-related macular degeneration (AMD).

  4. Cental Macular Thickness in Patients with Type 2 Diabetes Mellitus without Clinical Retinopathy.

    PubMed

    Demir, Mehmet; Dirim, Burcu; Acar, Zeynep; Yılmaz, Murat; Sendul, Yekta

    2013-01-01

    Objective. To compare central macular thickness (CMT) of diabetic patients with type 2 diabetes without clinical retinopathy and healthy subjects. Materials and Methods. Optical coherence tomography (OCT) measurements were performed in 124 eyes of 62 subjects with diabetes mellitus without clinical retinopathy (study group: 39 females, 23 males; mean age: 55.06 ± 9.77 years) and in 120 eyes of 60 healthy subjects (control group: 35 females, 25 males; mean age: 55.78 ± 10.34 years). Blood biochemistry parameters were analyzed in all cases. The data for central macular thickness (at 1 mm), the levels of fasting plasma glucose, and glycosylated hemoglobin (HbA1c) were compared in both groups. Results. The mean central macular thickness was 232.12 ± 24.41 µm in the study group and 227.19 ± 29.94 µm in the control group. The mean HbA1c level was 8.92 ± 2.58% in the study group and 5.07 ± 0.70% in the control group (P = 0.001). No statistically significant relationship was found between CMT, HbA1c, and fasting plasma glucose level in either group (P > 0.05). Conclusions. Central macular thickness was not significantly thicker in patients with type 2 diabetes without clinical retinopathy than in healthy subjects. PMID:23691279

  5. Structure and Conformation of the Carotenoids in Human Retinal Macular Pigment.

    PubMed

    Arteni, Ana-Andreea; Fradot, Mathias; Galzerano, Denise; Mendes-Pinto, Maria M; Sahel, José-Alain; Picaud, Serge; Robert, Bruno; Pascal, Andrew A

    2015-01-01

    Human retinal macular pigment (MP) is formed by the carotenoids lutein and zeaxanthin (including the isomer meso-zeaxanthin). MP has several functions in improving visual performance and protecting against the damaging effects of light, and MP levels are used as a proxy for macular health-specifically, to predict the likelihood of developing age-related macular degeneration. While the roles of these carotenoids in retinal health have been the object of intense study in recent years, precise mechanistic details of their protective action remain elusive. We have measured the Raman signals originating from MP carotenoids in ex vivo human retinal tissue, in order to assess their structure and conformation. We show that it is possible to distinguish between lutein and zeaxanthin, by their excitation profile (related to their absorption spectra) and the position of their ν1 Raman mode. In addition, analysis of the ν4 Raman band indicates that these carotenoids are present in a specific, constrained conformation in situ, consistent with their binding to specific proteins as postulated in the literature. We discuss how these conclusions relate to the function of these pigments in macular protection. We also address the possibilities for a more accurate, consistent measurement of MP levels by Raman spectroscopy.

  6. Psychosocial Intervention for Age-Related Macular Degeneration: A Pilot Project

    ERIC Educational Resources Information Center

    Wahl, Hans-Werner; Kammerer, Annette; Holz, Frank; Miller, Daniel; Becker, Stefanie; Kaspar, Roman; Himmelsbach, Ines

    2006-01-01

    This study evaluated an emotion-focused and a problem-focused intervention designed for patients with age-related macular degeneration. It found a limited decrease in depression in the emotion-focused group and an increase in active problem orientation and in adaptation to vision loss in the problem-focused group.

  7. The Psychosocial Impact of Closed-Circuit Televisions on Persons with Age-Related Macular Degeneration

    ERIC Educational Resources Information Center

    Huber, Jessica G.; Jutai, Jeffrey W.; Strong, J. Graham; Plotkin, Ann D.

    2008-01-01

    Closed-circuit televisions (CCTVs) are used by many elderly people who have age-related macular degeneration (AMD). The functional vision of 68 participants, which was measured immediately after they adopted CCTVs, suggested successful outcomes, but the psychosocial impact of the use of CCTVs did not peak until a month later. The findings help…

  8. Foveal-Sparing Scotomas in Advanced Dry Age-Related Macular Degeneration

    ERIC Educational Resources Information Center

    Sunness, Janet S.; Rubin, Gary S.; Zuckerbrod, Abraham; Applegate, Carol A.

    2008-01-01

    Foveal-sparing scotomas are common in advanced dry macular degeneration (geographic atrophy). Foveal preservation may be present for a number of years. Despite good visual acuity, these patients have reduced reading rates. Magnification may not be effective if the text becomes too large to "fit" within the central spared area. (Contains 2 tables…

  9. The Effect of an Educational Program for Persons with Macular Degeneration: A Pilot Study

    ERIC Educational Resources Information Center

    Smith, Theresa Marie; Thomas, Kimberly; Dow, Katherine

    2009-01-01

    Macular degeneration is the leading cause of vision loss in the United States for persons aged 60 and older. Compared to individuals without disabilities, individuals with low vision demonstrate a 15% to 30% higher dependence on others to perform activities of daily living. In addition, low vision can adversely affect a person's quality of life.…

  10. Lighting Needs and Lighting Comfort During Reading with Age-Related Macular Degeneration

    ERIC Educational Resources Information Center

    Fosse, Per; Valberg, Arne

    2004-01-01

    This study investigated the effects of changes in luminance on the oral reading speeds of 13 participants with age-related macular degeneration (AMD) and a control group of six age-matched persons with typical vision. For the AMD participants, self-reports of light preferences were also recorded. In the AMD group, reading rates depended on light…

  11. A Qualitative Analysis of Reading Rehabilitation of Persons with Age-Related Macular Degeneration

    ERIC Educational Resources Information Center

    Feely, Mary; Vetere, Arlene; Myers, Lynn B.

    2007-01-01

    One of the most prevalent visual impairments of people aged 60 and older is age-related macular degeneration (AMD), which ranks third globally as a cause of visual impairment (World Health Organization, 2006). The purpose of this study was to conduct a tentative subjective assessment of eccentric viewing by persons with AMD. The authors recruited…

  12. Structure and Conformation of the Carotenoids in Human Retinal Macular Pigment

    PubMed Central

    Arteni, Ana-Andreea; Fradot, Mathias; Galzerano, Denise; Mendes-Pinto, Maria M.; Sahel, José-Alain; Picaud, Serge; Robert, Bruno; Pascal, Andrew A.

    2015-01-01

    Human retinal macular pigment (MP) is formed by the carotenoids lutein and zeaxanthin (including the isomer meso-zeaxanthin). MP has several functions in improving visual performance and protecting against the damaging effects of light, and MP levels are used as a proxy for macular health–specifically, to predict the likelihood of developing age-related macular degeneration. While the roles of these carotenoids in retinal health have been the object of intense study in recent years, precise mechanistic details of their protective action remain elusive. We have measured the Raman signals originating from MP carotenoids in ex vivo human retinal tissue, in order to assess their structure and conformation. We show that it is possible to distinguish between lutein and zeaxanthin, by their excitation profile (related to their absorption spectra) and the position of their ν1 Raman mode. In addition, analysis of the ν4 Raman band indicates that these carotenoids are present in a specific, constrained conformation in situ, consistent with their binding to specific proteins as postulated in the literature. We discuss how these conclusions relate to the function of these pigments in macular protection. We also address the possibilities for a more accurate, consistent measurement of MP levels by Raman spectroscopy. PMID:26313550

  13. The short-wavelength mechanisms of Stiles in age-related macular degeneration.

    PubMed

    Hubschman, J P; Vola, J L; Conrath, J; Berros, P; Hougrand, F

    1998-11-01

    Clinical measurements by the increment-threshold technique of W.S. Stiles are reported in five cases of age-related macular degeneration. Measurements were made on a modified Tübingen perimeter using 1 degree, short-wavelength targets presented on a red field.

  14. Knowledge and Use of Low Vision Services Among Persons with Age-Related Macular Degeneration

    ERIC Educational Resources Information Center

    Casten, Robin J.; Maloney, Eileen K.; Rovner, Barry W.

    2005-01-01

    Visual impairment (blindness or low vision) is a leading cause of disability among older adults and is most often due to age-related macular degeneration (AMD). It is predicted that 2.95 million people will have AMD by 2020 (Eye Diseases Prevalence Research Group, 2004). Unfortunately, there is no cure for AMD, nor can lost vision be restored.…

  15. In vivo snapshot hyperspectral image analysis of age-related macular degeneration.

    PubMed

    Lee, N; Wielaard, J; Fawzi, A A; Sajda, P; Laine, A F; Martin, G; Humayun, M S; Smith, R T

    2010-01-01

    Drusen, the hallmark lesions of age related macular degeneration (AMD), are biochemically heterogeneous and the identification of their biochemical distribution is key to the understanding of AMD. Yet the challenges are to develop imaging technology and analytics, which respect the physical generation of the hyperspectral signal in the presence of noise, artifacts, and multiple mixed sources while maximally exploiting the full data dimensionality to uncover clinically relevant spectral signatures. This paper reports on the statistical analysis of hyperspectral signatures of drusen and anatomical regions of interest using snapshot hyperspectral imaging and non-negative matrix factorization (NMF). We propose physical meaningful priors as initialization schemes to NMF for finding low-rank decompositions that capture the underlying physiology of drusen and the macular pigment. Preliminary results show that snapshot hyperspectral imaging in combination with NMF is able to detect biochemically meaningful components of drusen and the macular pigment. To our knowledge, this is the first reported demonstration in vivo of the separate absorbance peaks for lutein and zeaxanthin in macular pigment.

  16. Candidate gene study of macular response to supplemental lutein and zeaxanthin.

    PubMed

    Yonova-Doing, Ekaterina; Hysi, Pirro G; Venturini, Cristina; Williams, Katie M; Nag, Abhishek; Beatty, Stephen; Liew, S H Melissa; Gilbert, Clare E; Hammond, Christopher J

    2013-10-01

    Supplementation with carotenoids is proposed to protect against age-related macular degeneration. There is, however, considerable variability in retinal macular pigment response, which may be due to underlying genetic variation. The purpose of this study was to determine whether genetic factors, which have been previously associated with cross-sectional macular pigment levels in the retina or serum lutein, also influence response to supplementation. To this end we conducted an association study in 310 subjects from the TwinsUK cohort between variants in 8 candidate genes and serum lutein and retinal macular pigment optical density (MPOD) levels before and after supplementation. Four variants were associated with MPOD response to supplementation (p < 0.05): rs11057841 (SCARB1), rs4926339 (RPE65), rs1929841 (ABCA1) and rs174534 (FADS1). We also confirmed previous associations between rs6564851 near BMCO1 (p < 0.001) and rs11057841 within SCARB1 (p = 0.01) and baseline measures of serum lutein; while the latter was also associated with MPOD response, none of the BMCO1 variants were. Finally, there was evidence for association between variants near RPE65 and ELOVL2 and changes in lutein concentration after supplementation. This study is the first to show association between genetic variants and response to carotenoids supplementation. Our findings suggest an important link between MP response and the biological processes of carotenoids transport and fatty acid metabolism.

  17. Macular thickness as a predictor of loss of visual sensitivity in ethambutol-induced optic neuropathy.

    PubMed

    Peng, Chun-Xia; Zhang, Ai-di; Chen, Bing; Yang, Bing-Jian; Wang, Qiu-Hong; Yang, Mo; Wei, Shi-Hui

    2016-03-01

    Ethambutol is a common cause of drug-related optic neuropathy. Prediction of the onset of ethambutol-induced optic neuropathy and consequent drug withdrawal may be an effective method to stop visual loss. Previous studies have shown that structural injury to the optic nerve occurred earlier than the damage to visual function. Therefore, we decided to detect structural biomarkers marking visual field loss in early stage ethambutol-induced optic neuropathy. The thickness of peripapillary retinal nerve fiber layer, macular thickness and visual sensitivity loss would be observed in 11 ethambutol-induced optic neuropathy patients (22 eyes) using optical coherence tomography. Twenty-four healthy age- and sex-matched participants (48 eyes) were used as controls. Results demonstrated that the temporal peripapillary retinal nerve fiber layer thickness and average macular thickness were thinner in patients with ethambutol-induced optic neuropathy compared with healthy controls. The average macular thickness was strongly positively correlated with central visual sensitivity loss (r (2) =0.878, P=0.000). These findings suggest that optical coherence tomography can be used to efficiently screen patients. Macular thickness loss could be a potential factor for predicting the onset of ethambutol-induced optic neuropathy. PMID:27127488

  18. Diminishing risk for age related macular degeneration with nutrition: A current view

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Age-related macular degeneration (AMD) is the leading cause of blindness in the elderly. Clinical hallmarks of AMD are observed in one third of the elderly in industrialized countries. Preventative interventions through dietary modification are attractive strategies because they are more affordable...

  19. Macular thickness as a predictor of loss of visual sensitivity in ethambutol-induced optic neuropathy

    PubMed Central

    Peng, Chun-xia; Zhang, Ai-di; Chen, Bing; Yang, Bing-jian; Wang, Qiu-hong; Yang, Mo; Wei, Shi-hui

    2016-01-01

    Ethambutol is a common cause of drug-related optic neuropathy. Prediction of the onset of ethambutol-induced optic neuropathy and consequent drug withdrawal may be an effective method to stop visual loss. Previous studies have shown that structural injury to the optic nerve occurred earlier than the damage to visual function. Therefore, we decided to detect structural biomarkers marking visual field loss in early stage ethambutol-induced optic neuropathy. The thickness of peripapillary retinal nerve fiber layer, macular thickness and visual sensitivity loss would be observed in 11 ethambutol-induced optic neuropathy patients (22 eyes) using optical coherence tomography. Twenty-four healthy age- and sex-matched participants (48 eyes) were used as controls. Results demonstrated that the temporal peripapillary retinal nerve fiber layer thickness and average macular thickness were thinner in patients with ethambutol-induced optic neuropathy compared with healthy controls. The average macular thickness was strongly positively correlated with central visual sensitivity loss (r2 =0.878, P=0.000). These findings suggest that optical coherence tomography can be used to efficiently screen patients. Macular thickness loss could be a potential factor for predicting the onset of ethambutol-induced optic neuropathy. PMID:27127488

  20. The Determinants of Macular and Peripapillary Retinal Thickness Using Optical Coherence Tomography.

    PubMed

    Nakhjavanpour, Neda; Sedaghat, Mohammad Reza; Payandeh, Abolfazl; Ostadimoghaddam, Hadi

    2016-01-01

    Retinal nerve fiber layer thickness is an important factor in early diagnosis of posterior pole dysfunctions, assessment of treatment effect, and disease progress. The aim of this study was to compare the macular and peripapillary retinal thickness between genders and among refractive error types in healthy subjects. In addition, effective determinants of the thickness were ascertained. This cross-sectional study was conducted on 58 subjects (116 eyes), which had been referred to the Toos eye clinic of Mashhad, northeast of Iran, for refractive error surgery from September 2012 to June 2013. We used Optical Coherence Tomography for retinal thickness measurements. The mean±SD spherical equivalence was estimated to be -2.06±0.36 dioptres (range: -11.50, 7.38), axial length 23.89±0.14 mm, average peripapillary thickness 89.91±0.94 μm, average macular thickness 274.68±1.84 μm, and overall macular volume 9.89±0.07 mm3.Multiple linear regression modeling was indicated that axial length and gender had significant effect on average macular thickness. Axial length also showed substantial effect on average peripapillary thickness. Retinal thickness measurement regardless of refractive error type could lead to bias in disease diagnosis. The results of the present study might be used to enhance the assessment precision of ocular diseases. PMID:27530565

  1. Retinal Nerve Fibre Layer and Macular Thicknesses in Adults with Hyperopic Anisometropic Amblyopia

    PubMed Central

    Yakar, Konuralp; Alan, Aydın; Alp, Mehmet Hanifi; Ceylan, Tolga

    2015-01-01

    Objectives. This study compared the macular and retinal nerve fibre layer (RNFL) thicknesses and optic nerves of eyes with reduced vision due to anisometropia with the contralateral healthy eyes in adults using optical coherence tomography (OCT). Methods. This cross-sectional study was conducted in Atatürk State Hospital, Sinop, Turkey. Macular and RNFL thicknesses, optic nerve disc area, cup area, and horizontal and vertical cup-to-disc ratios obtained using a NIDEK RS-3000 SLO spectral domain OCT device were compared between the amblyopic and fellow eyes in 30 adults with anisometropic amblyopia 18–55 years old who were seen in our clinic with unilateral poor vision. Results. The mean macular thickness was 266.90 ± 23.22 µm in the amblyopic eyes and 263.90 ± 22.84 µm in the fellow eyes, and the mean RNFL thickness was 111.90 ± 12.9 and 109.70 ± 9.42 µm, respectively. The two thicknesses did not differ significantly between the amblyopic and fellow eyes. There were also no significant differences between the eyes in disc area, cup area, and horizontal-vertical cup/disc ratios. Conclusion. There does not seem to be a difference in macular thickness, peripapillary RNFL, or optic disc structures between the amblyopic and fellow eyes in adults. PMID:26064676

  2. Introduction to the issue regarding research regarding age related macular degeneration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Blindness is the second greatest fear among the elderly. Age-related macular degeneration (AMD) is the leading cause of vision loss among the elderly in most industrialized nations. AMD first compromises central high acuity vision. Subsequently, all vision may be lost. AMD is a progressive retinal d...

  3. The relationship of major American dietary patterns to age-related macular degeneration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We hypothesized that major American dietary patterns are associated with age-related macular degeneration (AMD) risk. This was a cross-sectional study with 8,103 eyes from 4,088 eligible participants in the baseline Age-Related Eye Disease Study (AREDS) were classified into control (n=2,739), early ...

  4. Chromatic multifocal pupillometer for objective perimetry in patients with macular degeneration (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Rotenstreich, Ygal; Ben-Ner, Daniel; Mahajna, Mohamad; Chibel, Ron; Sher, Ifat

    2016-03-01

    Purpose: To objectively assess visual field (VF) defects and retinal cell function in healthy subjects and patients with macular degeneration using a chromatic multifocal pupillometer. Methods: A multifocal chromatic pupillometer (MCP) was used to record pupillary responses (PR) of 17 healthy subjects and 5 Best Vitelliform macular dystrophy patients. Blue and red light stimuli (peak 485nm and 620nm, respectively) were presented at light intensities of 400 and 1000 cd/m2, respectively at 76 different points in a 16.2 degree VF. The PR of patients were compared with their findings on Humphrey's 24-2 perimetry, optical coherence tomography and the PR obtained from healthy subjects. Results: Patients demonstrated reduced percentage of pupillary contraction and slower maximal contraction velocity, more than two standard errors (SE) away from the mean of healthy subjects in response to red light in majority of VF locations. In response to blue light, the percentage of pupillary contraction was lower (by over two SE) compared with normal controls only in central locations. The latency of maximal contraction velocity was shorter in patients compared with healthy subjects in response to both colors. Conclusions: This study demonstrated the advantage of using MCP-based objective VF to assess central scotoma in macular degeneration. Our finding also suggests that chromatic perimetry may differentiate between PR mediated by cones and rods, and can specifically detect defects in macular cones. Different parameters of PR such as latency of maximal contraction velocity may shed light on the pathophysiology of different blinding diseases.

  5. Comparison of the Efficacy of Intravitreal Aflibercept and Bevacizumab for Macular Edema Secondary to Branch Retinal Vein Occlusion.

    PubMed

    Wang, Jia-Kang; Su, Pei-Yuan; Hsu, Yung-Ray; Chen, Yun-Ju; Chen, Fang-Ting; Tseng, Ying-Yu

    2016-01-01

    Fifty-two eyes of 52 patients with treatment-naïve macular edema associated with perfused branch retinal vein occlusion were retrospectively reviewed. Twenty-seven cases received PRN intravitreal bevacizumab, and 25 cases were treated by PRN intravitreal aflibercept with monthly follow-ups for 12 months. Both aflibercept and bevacizumab were effective in reduction of macular thickness and improvement of visual acuity for the participants. Both antivascular endothelial growth factor agents had similar efficacy and duration of treatment for these eyes with macular edema secondary to branch retinal vein occlusion during a 12-month period. No serious systemic or ocular adverse events were reported. PMID:27190640

  6. An updated review of long-term outcomes from randomized controlled trials in approved pharmaceuticals for diabetic macular edema.

    PubMed

    Wang, Jia-Kang; Huang, Tzu-Lun; Su, Pei-Yuan; Chang, Pei-Yao

    2015-12-01

    Diabetic macular edema (DME) is a major sight-threatening cause in diabetic patients. We review the long-term outcome of four approved pharmacotherapy for treating DME, including intravitreal injections of corticosteroids (dexamethasone implants and fluocinolone acetonide inserts) and anti-vascular endothelial growth factor (VEGF) (ranibizumab and aflibercept). They all show superior ability to improve vision and reduce macular thickness, comparing with sham injections or macular focal/grid laser treatment. Anti-VEGF agents result in low incidence of severe ocular or systemic adverse effects, but glaucoma and cataract should be aware after intravitreal corticosteroids. Prompt treatment with these agents can lead to a better outcome PMID:27215008

  7. Oxidative stress, innate immunity, and age-related macular degeneration

    PubMed Central

    Shaw, Peter X.; Stiles, Travis; Douglas, Christopher; Ho, Daisy; Fan, Wei; Du, Hongjun; Xiao, Xu

    2016-01-01

    Age-related macular degeneration (AMD) is a leading cause of vision loss affecting tens of millions of elderly worldwide. Early AMD is characterized by the appearance of soft drusen, as well as pigmentary changes in the retinal pigment epithelium (RPE). These soft, confluent drusen can progress into two forms of advanced AMD: geographic atrophy (GA, or dry AMD) or choroidal neovascularization (CNV, or wet AMD). Both forms of AMD result in a similar clinical progression in terms of loss of central vision. The exact mechanism for developing early AMD, as well as triggers responsible for progressing to advanced stage of disease, is still largely unknown. However, significant evidence exists demonstrating a complex interplay of genetic and environmental factors as causes of AMD progression. Multiple genes and/or single nucleotide polymorphisms (SNPs) have been found associated with AMD, including various genes involved in the complement pathway, lipid metabolism and extracellular matrix (ECM) remodeling. Of the known genetic contributors to disease risk, the CFH Y402H and HTRA1/ARMS polymorphisms contribute to more than 50% of the genetic risk for AMD. Environmentally, oxidative stress plays a critical role in many aging diseases including cardiovascular disease, cancer, Alzheimer’s disease and AMD. Due to the exposure to sunlight and high oxygen concentration, the oxidative stress burden is higher in the eye than other tissues, which can be further complicated by additional oxidative stressors such as smoking. Increasingly, evidence is accumulating suggesting that functional abnormalities of the innate immune system incurred via high risk genotypes may be contributing to the pathogenesis of AMD by altering the inflammatory homeostasis in the eye, specifically in the handling of oxidation products. As the eye in non-pathological instances maintains a low level of inflammation despite the presence of a relative abundance of potentially inflammatory molecules, we have

  8. Progress on retinal image analysis for age related macular degeneration.

    PubMed

    Kanagasingam, Yogesan; Bhuiyan, Alauddin; Abràmoff, Michael D; Smith, R Theodore; Goldschmidt, Leonard; Wong, Tien Y

    2014-01-01

    Age-related macular degeneration (AMD) is the leading cause of vision loss in those over the age of 50 years in the developed countries. The number is expected to increase by ∼1.5 fold over the next ten years due to an increase in aging population. One of the main measures of AMD severity is the analysis of drusen, pigmentary abnormalities, geographic atrophy (GA) and choroidal neovascularization (CNV) from imaging based on color fundus photograph, optical coherence tomography (OCT) and other imaging modalities. Each of these imaging modalities has strengths and weaknesses for extracting individual AMD pathology and different imaging techniques are used in combination for capturing and/or quantification of different pathologies. Current dry AMD treatments cannot cure or reverse vision loss. However, the Age-Related Eye Disease Study (AREDS) showed that specific anti-oxidant vitamin supplementation reduces the risk of progression from intermediate stages (defined as the presence of either many medium-sized drusen or one or more large drusen) to late AMD which allows for preventative strategies in properly identified patients. Thus identification of people with early stage AMD is important to design and implement preventative strategies for late AMD, and determine their cost-effectiveness. A mass screening facility with teleophthalmology or telemedicine in combination with computer-aided analysis for large rural-based communities may identify more individuals suitable for early stage AMD prevention. In this review, we discuss different imaging modalities that are currently being considered or used for screening AMD. In addition, we look into various automated and semi-automated computer-aided grading systems and related retinal image analysis techniques for drusen, geographic atrophy and choroidal neovascularization detection and/or quantification for measurement of AMD severity using these imaging modalities. We also review the existing telemedicine studies which

  9. A twin study on age-related macular degeneration.

    PubMed Central

    Meyers, S M

    1994-01-01

    A prospective twin study on age-related macular degeneration (AMD) recruited 83 monozygotic pairs, 28 dizygotic pairs, and one triplet set from 1986 through 1993. Zygosity was determined by genetic testing of red cell markers, HLA antigens, or specific DNA loci. There were no twin pairs in which I collected data on only one twin. To decrease ascertainment bias, after 1991 the recruitment notice did not mention AMD, and I did not ask about a history of eye disease before the eye examination. Because of this, twin pairs recruited from 1986 through 1991 were statistically analyzed separately from those after January 1, 1992. From 1986 through 1991, 23 twin pairs were recruited; 11 monozygotic and 2 dizygotic pairs had nonAMD retinal changes or no retinal abnormalities, 9 monozygotic pairs with AMD were all concordant, and 1 dizygotic pair was discordant for basal laminar drusen. The concordance rate of AMD did not differ significantly between monozygotic and dizygotic twin pairs (P = .10) for 1986 through 1991. In 1992 and 1993, 88 twin pairs and one triplet set were recruited; 49 monozygotic and 19 dizygotic pairs had nonAMD retinal changes or no retinal abnormalities, 14 monozygotic pairs with AMD were all concordant, and 2 of 7 dizygotic pairs were concordant for AMD. The nonidentical triplets (1 with and 2 without AMD) were categorized as one of the discordant dizygotic pairs in the statistical evaluation. In nontwin age-matched (within 2 or 5 years of age) or age- and sex-matched sibling pairs the concordance rate of AMD ranged from 16% to 25%. The concordance rate of AMD was significantly higher in monozygotic than in dizygotic twins (P = .001) for 1992 and 1993. The concordance rate was higher for monozygotic twin pairs recruited in 1992 and 1993 than in any of the four subsets of nontwin age-method or age- and sex-matched sibling pairs (P < .0001). Overall, from 1986 through 1993, 23 of 23 monozygotic and 2 of 8 dizygotic twin pairs were concordant for AMD

  10. Interplanetary magnetic holes: Theory

    NASA Technical Reports Server (NTRS)

    Burlaga, L. F.; Lemaire, J. F.

    1978-01-01

    Magnetic holes in the interplanetary medium are explained as stationary, non-propagating, equilibrium structures in which there are field-aligned enhancements of the plasma density and/or temperature. Magnetic anti-holes are considered to be associated with depressions in the plasma pressure. In this model, the observed changes in the magnetic field intensity and direction are due to diamagnetic currents that are carried by ions which drift in a sheath as the result of gradients in the magnetic field and in the plasma pressure within the sheath. The thickness of the sheaths considered is approximately a few ion Larmor radii. An electric field is normal to the magnetic field in the sheath. Solutions of Vlasov's equation and Maxwell's equations are presented which account for several types of magnetic holes, including null-sheets, that were observed.

  11. Merging Black Holes

    NASA Technical Reports Server (NTRS)

    Centrella, Joan

    2012-01-01

    The final merger of two black holes is expected to be the strongest source of gravitational waves for both ground-based detectors such as LIGO and VIRGO, as well as future. space-based detectors. Since the merger takes place in the regime of strong dynamical gravity, computing the resulting gravitational waveforms requires solving the full Einstein equations of general relativity on a computer. For many years, numerical codes designed to simulate black hole mergers were plagued by a host of instabilities. However, recent breakthroughs have conquered these instabilities and opened up this field dramatically. This talk will focus on.the resulting 'gold rush' of new results that is revealing the dynamics and waveforms of binary black hole mergers, and their applications in gravitational wave detection, testing general relativity, and astrophysics

  12. Merging Black Holes

    NASA Technical Reports Server (NTRS)

    Centrella, Joan

    2010-01-01

    The final merger of two black holes is expected to be the strongest source of gravitational waves for both ground-based detectors such as LIGO and VIRGO, as well as the space-based LISA. Since the merger takes place in the regime of strong dynamical gravity, computing the resulting gravitational waveforms requires solving the full Einstein equations of general relativity on a computer. For many years, numerical codes designed to simulate black hole mergers were plagued by a host of instabilities. However, recent breakthroughs have conquered these instabilities and opened up this field dramatically. This talk will focus on the resulting gold rush of new results that are revealing the dynamics and waveforms of binary black hole mergers, and their applications in gravitational wove detection, testing general relativity, and astrophysics.

  13. Turbulent black holes.

    PubMed

    Yang, Huan; Zimmerman, Aaron; Lehner, Luis

    2015-02-27

    We demonstrate that rapidly spinning black holes can display a new type of nonlinear parametric instability-which is triggered above a certain perturbation amplitude threshold-akin to the onset of turbulence, with possibly observable consequences. This instability transfers from higher temporal and azimuthal spatial frequencies to lower frequencies-a phenomenon reminiscent of the inverse cascade displayed by (2+1)-dimensional fluids. Our finding provides evidence for the onset of transitory turbulence in astrophysical black holes and predicts observable signatures in black hole binaries with high spins. Furthermore, it gives a gravitational description of this behavior which, through the fluid-gravity duality, can potentially shed new light on the remarkable phenomena of turbulence in fluids.

  14. Turbulent black holes.

    PubMed

    Yang, Huan; Zimmerman, Aaron; Lehner, Luis

    2015-02-27

    We demonstrate that rapidly spinning black holes can display a new type of nonlinear parametric instability-which is triggered above a certain perturbation amplitude threshold-akin to the onset of turbulence, with possibly observable consequences. This instability transfers from higher temporal and azimuthal spatial frequencies to lower frequencies-a phenomenon reminiscent of the inverse cascade displayed by (2+1)-dimensional fluids. Our finding provides evidence for the onset of transitory turbulence in astrophysical black holes and predicts observable signatures in black hole binaries with high spins. Furthermore, it gives a gravitational description of this behavior which, through the fluid-gravity duality, can potentially shed new light on the remarkable phenomena of turbulence in fluids. PMID:25768746

  15. Bringing Black Holes Home

    NASA Astrophysics Data System (ADS)

    Furmann, John M.

    2003-03-01

    Black holes are difficult to study because they emit no light. To overcome this obstacle, scientists are trying to recreate a black hole in the laboratory. The article gives an overview of the theories of Einstein and Hawking as they pertain to the construction of the Large Hadron Collider (LHC) near Geneva, Switzerland, scheduled for completion in 2006. The LHC will create two beams of protons traveling in opposing directions that will collide and create a plethora of scattered elementary particles. Protons traveling in opposite directions at very high velocities may create particles that come close enough to each other to feel their compacted higher dimensions and create a mega force of gravity that can create tiny laboratory-sized black holes for fractions of a second. The experiments carried out with LHC will be used to test modern string theory and relativity.

  16. Black-hole astrophysics

    SciTech Connect

    Bender, P.; Bloom, E.; Cominsky, L.

    1995-07-01

    Black-hole astrophysics is not just the investigation of yet another, even if extremely remarkable type of celestial body, but a test of the correctness of the understanding of the very properties of space and time in very strong gravitational fields. Physicists` excitement at this new prospect for testing theories of fundamental processes is matched by that of astronomers at the possibility to discover and study a new and dramatically different kind of astronomical object. Here the authors review the currently known ways that black holes can be identified by their effects on their neighborhood--since, of course, the hole itself does not yield any direct evidence of its existence or information about its properties. The two most important empirical considerations are determination of masses, or lower limits thereof, of unseen companions in binary star systems, and measurement of luminosity fluctuations on very short time scales.

  17. Ozone Hole Over Antarctica

    NASA Technical Reports Server (NTRS)

    2002-01-01

    These images from the Total Ozone Mapping Spectrometer (TOMS) show the progressive depletion of ozone over Antarctica from 1979 to 1999. This 'ozone hole' has extended to cover an area as large as 10.5 million square miles in September 1998. The previous record of 10.0 million square miles was set in 1996. The Antarctic ozone hole develops each year between late August and early October. Regions with higher levels of ozone are shown in red. NASA and NOAA instruments have been measuring Antarctic ozone levels since the early 1970s. Large regions of depleted ozone began to develop over Antarctica in the early 1980s. Ozone holes of substantial size and depth are likely to continue to form during the next few years, scientists hope to see a reduction in ozone loss as levels of ozone-destroying CFCs (chlorofluorocarbons) are gradually reduced. Credit: Images by Greg Shirah, NASA Goddard Space Flight Center Scientific Visualization Studio

  18. Janus black holes

    NASA Astrophysics Data System (ADS)

    Bak, Dongsu; Gutperle, Michael; Janik, Romuald A.

    2011-10-01

    In this paper Janus black holes in A dS 3 are considered. These are static solutions of an Einstein-scalar system with broken translation symmetry along the horizon. These solutions are dual to interface conformal field theories at finite temperature. An approximate solution is first constructed using perturbation theory around a planar BTZ blackhole. Numerical and exact solutions valid for all sets of parameters are then found and compared. Using the exact solution the thermodynamics of the system is analyzed. The entropy associated with the Janus black hole is calculated and it is found that the entropy of the black Janus is the sum of the undeformed black hole entropy and the entanglement entropy associated with the defect.

  19. Slowly balding black holes

    SciTech Connect

    Lyutikov, Maxim; McKinney, Jonathan C.

    2011-10-15

    The 'no-hair' theorem, a key result in general relativity, states that an isolated black hole is defined by only three parameters: mass, angular momentum, and electric charge; this asymptotic state is reached on a light-crossing time scale. We find that the no-hair theorem is not formally applicable for black holes formed from the collapse of a rotating neutron star. Rotating neutron stars can self-produce particles via vacuum breakdown forming a highly conducting plasma magnetosphere such that magnetic field lines are effectively ''frozen in'' the star both before and during collapse. In the limit of no resistivity, this introduces a topological constraint which prohibits the magnetic field from sliding off the newly-formed event horizon. As a result, during collapse of a neutron star into a black hole, the latter conserves the number of magnetic flux tubes N{sub B}=e{Phi}{sub {infinity}}/({pi}c({h_bar}/2{pi})), where {Phi}{sub {infinity}}{approx_equal}2{pi}{sup 2}B{sub NS}R{sub NS}{sup 3}/(P{sub NS}c) is the initial magnetic flux through the hemispheres of the progenitor and out to infinity. We test this theoretical result via 3-dimensional general relativistic plasma simulations of rotating black holes that start with a neutron star dipole magnetic field with no currents initially present outside the event horizon. The black hole's magnetosphere subsequently relaxes to the split-monopole magnetic field geometry with self-generated currents outside the event horizon. The dissipation of the resulting equatorial current sheet leads to a slow loss of the anchored flux tubes, a process that balds the black hole on long resistive time scales rather than the short light-crossing time scales expected from the vacuum no-hair theorem.

  20. Growth of Primordial Black Holes

    NASA Astrophysics Data System (ADS)

    Harada, Tomohiro

    Primordial black holes have important observational implications through Hawking evaporation and gravitational radiation as well as being a candidate for cold dark matter. Those black holes are assumed to have formed in the early universe typically with the mass scale contained within the Hubble horizon at the formation epoch and subsequently accreted mass surrounding them. Numerical relativity simulation shows that primordial black holes of different masses do not accrete much, which contrasts with a simplistic Newtonian argument. We see that primordial black holes larger than the 'super-horizon' primordial black holes have decreasing energy and worm-hole like struture, suggesting the formation through quamtum processes.

  1. Analysis of Macular Drusen and Blood Test Results in 945 Macaca fascicularis

    PubMed Central

    Nishiguchi, Koji M.; Yokoyama, Yu; Fujii, Yusuke; Fujita, Kosuke; Tomiyama, Yusuke; Kawasaki, Ryo; Furukawa, Toshinori; Ono, Fumiko; Shimozawa, Nobuhiro; Togo, Mutsumi; Suzuki, Michihiro; Nakazawa, Toru

    2016-01-01

    Age-dependent formation of macular drusen caused by the focal accumulation of extracellular deposits beneath the retinal pigment epithelium precede the development of age-related macular degeneration (AMD), one of the leading causes of blindness worldwide. It is established that inflammation contributes to the pathogenesis of drusen and AMD. However, development of a preemptive therapeutic strategy targeting macular drusen and AMD has been impeded by the lack of relevant animal models because most laboratory animals lack macula, an anatomic feature present only in humans and a subset of monkeys. Reportedly, macular drusen and macular degeneration develop in monkeys in an age-dependent manner. In this study, we analyzed blood test results from 945 Macaca fascicularis, 317 with and 628 without drusen. First, a trend test for drusen frequency (the Cochran–Armitage test) was applied to the quartile data for each parameter. We selected variables with an increasing or decreasing trend with higher quartiles at P < 0.05, to which multivariate logistic regression analysis was applied. This revealed a positive association of age (odds ratio [OR]: 1.10 per year, 95% confidence interval [CI]: 1.07–1.12) and white blood cell count (OR: 1.01 per 1 × 103/μl, 95% CI: 1.00–1.01) with drusen. When the monkeys were divided by age, the association between drusen and white blood cell count was only evident in younger monkeys (OR: 1.01 per 1 × 103/μl, 95% CI: 1.00–1.02). In conclusion, age and white blood cell count may be associated with drusen development in M. fascicularis. Systemic inflammation may contribute to drusen formation in monkeys. PMID:27776188

  2. CYP4F2 (rs2108622) Gene Polymorphism Association with Age-Related Macular Degeneration.

    PubMed

    Sakiene, Ruta; Vilkeviciute, Alvita; Kriauciuniene, Loresa; Balciuniene, Vilma Jurate; Buteikiene, Dovile; Miniauskiene, Goda; Liutkeviciene, Rasa

    2016-01-01

    Background. Age-related macular degeneration is the leading cause of blindness in elderly individuals where aetiology and pathophysiology of age-related macular degeneration are not absolutely clear. Purpose. To determine the frequency of the genotype of rs2108622 in patients with early and exudative age-related macular degeneration. Methods. The study enrolled 190 patients with early age-related macular degeneration, 181 patients with exudative age-related macular degeneration (eAMD), and a random sample of 210 subjects from the general population (control group). The genotyping of rs2108622 was carried out using the real-time polymerase chain reaction method. Results. The analysis of rs2108622 gene polymorphism did not reveal any differences in the distribution of C/C, C/T, and T/T genotypes between the early AMD group, the eAMD group, and the control group. The CYP4F2 (1347C>T) T/T genotype was more frequent in males with eAMD compared to females (10.2% versus 0.8%; p = 0.0052); also T/T genotype was less frequently present in eAMD females compared to healthy control females (0.8% versus 6.2%; p = 0.027). Conclusion. Rs2108622 gene polymorphism had no predominant effect on the development of early AMD and eAMD. The T/T genotype was more frequent in males with eAMD compared to females and less frequently present in eAMD females compared to healthy females. PMID:27652291

  3. Topical Latanoprost Does Not Cause Macular Thickening after Uncomplicated Cataract Surgery

    PubMed Central

    Moghimi, Sasan; Zandian, Mehdi; Latifi, Golshan; Amini, Heydar; Eslami, Yadollah; Zarei, Reza; Fakhraie, Ghasem; Nouri-Mahdavi, Kouros

    2012-01-01

    Purpose To explore changes in central macular thickness (CMT) after a two-month period of glaucoma therapy with topical latanoprost after uneventful phacoemulsification. Methods Forty-one eyes of 31 patients with primary open angle or pseudoexfoliative glaucoma who required glaucoma medications after cataract surgery were prospectively enrolled. All eyes had undergone uneventful phacoemulsification with intraocular lens implantation at least 4 months before initiation of latanoprost. After a complete ophthalmic examination, spectral-domain optical coherence tomography (SD-OCT) and fluorescein angiography (FA) were performed at baseline before starting latanoprost. All eyes received latanoprost for 2 months, and clinical examinations were repeated one and two months afterwards; OCT and FA were repeated after 2 months. Outcome measures were CMT and loss of more than 2 lines of best corrected visual acuity (BCVA). Results Mean patient age was 71.6±7.8 years. Intraocular pressure decreased from 21.5±3.4 mmHg to 14.4±2.6 mmHg (p<0.001) at 2 months. None of the eyes developed reduction of BCVA exceeding 2 lines, or angiographic cystoid macular edema (CME). Likewise no significant change was noted in CMT (249.9±29.8 vs 248.8±30.7µm), average macular thickness (274.5±15.0 vs 273.8±17.0µm), or macular volume (9.6±1.0 vs 9.6±1.1µm2) after treatment as compared to baseline (P>0.05 for all comparisons). Conclusion Topical use of latanoprost later than 4 months after uncomplicated cataract surgery does not seem to predispose to increased macular thickness or CME and may safely be used in this setting. PMID:23503128

  4. Autologous platelet concentrate in surgery for macular detachment associated with congenital optic disc pit

    PubMed Central

    Nadal, Jeroni; Figueroa, Marta S; Carreras, Elisa; Pujol, Patricia; Canut, Maria Isabel; Barraquer, Rafael Ignacio

    2015-01-01

    Purpose To evaluate the anatomical and functional results obtained with pars plana vitrectomy (PPV) plus autologous platelet concentrate (APC) as a treatment for macular detachment associated with optic disc pit (ODP). Methods We performed a prospective interventional study of 19 eyes of 19 consecutive patients with posterior macular detachment due to ODP. All patients underwent PPV, posterior hyaloid peeling, fluid–air exchange, injection of 0.05 mL of APC over the ODP and 15% perfluoropropane (C3F8) endotamponade. Postoperative measures included face-up positioning for 2 hours and then avoidance of the face-up position during the ensuing 10 days. All patients underwent complete ophthalmologic examination and optical coherence tomography preoperatively at 1 month, 3 months, 6 months, 9 months, and 12 months postoperatively and then annually. Outcome measures were best corrected visual acuity (BCVA) by logMAR, improvement of quality of vision, macular attachment, and resolution of intraretinal schisis-like separation. Results Preoperatively, the median BCVA was 0.70 (range: 0.30–1.70) and all patients showed improved visual acuity after surgery; BCVA was 0.22 (range: 0.07–0.52) at 12 months follow-up. All patients showed complete reabsorption of intraretinal fluid (median time: 3.5 months [range: 2–8 months]) and macular attachment at the end of follow-up (median: 60 months [range: 12–144 months]), with stable or improved visual acuity. No reoperations were needed and no major adverse events were recorded. Conclusion For macular detachment associated with ODP, the combination of PPV, posterior hyaloid peeling, APC, and C3F8 tamponade is a highly effective alternative technique with stable anatomical and functional results. PMID:26543348

  5. CYP4F2 (rs2108622) Gene Polymorphism Association with Age-Related Macular Degeneration

    PubMed Central

    Kriauciuniene, Loresa; Balciuniene, Vilma Jurate; Buteikiene, Dovile; Miniauskiene, Goda; Liutkeviciene, Rasa

    2016-01-01

    Background. Age-related macular degeneration is the leading cause of blindness in elderly individuals where aetiology and pathophysiology of age-related macular degeneration are not absolutely clear. Purpose. To determine the frequency of the genotype of rs2108622 in patients with early and exudative age-related macular degeneration. Methods. The study enrolled 190 patients with early age-related macular degeneration, 181 patients with exudative age-related macular degeneration (eAMD), and a random sample of 210 subjects from the general population (control group). The genotyping of rs2108622 was carried out using the real-time polymerase chain reaction method. Results. The analysis of rs2108622 gene polymorphism did not reveal any differences in the distribution of C/C, C/T, and T/T genotypes between the early AMD group, the eAMD group, and the control group. The CYP4F2 (1347C>T) T/T genotype was more frequent in males with eAMD compared to females (10.2% versus 0.8%; p = 0.0052); also T/T genotype was less frequently present in eAMD females compared to healthy control females (0.8% versus 6.2%; p = 0.027). Conclusion. Rs2108622 gene polymorphism had no predominant effect on the development of early AMD and eAMD. The T/T genotype was more frequent in males with eAMD compared to females and less frequently present in eAMD females compared to healthy females.

  6. CYP4F2 (rs2108622) Gene Polymorphism Association with Age-Related Macular Degeneration.

    PubMed

    Sakiene, Ruta; Vilkeviciute, Alvita; Kriauciuniene, Loresa; Balciuniene, Vilma Jurate; Buteikiene, Dovile; Miniauskiene, Goda; Liutkeviciene, Rasa

    2016-01-01

    Background. Age-related macular degeneration is the leading cause of blindness in elderly individuals where aetiology and pathophysiology of age-related macular degeneration are not absolutely clear. Purpose. To determine the frequency of the genotype of rs2108622 in patients with early and exudative age-related macular degeneration. Methods. The study enrolled 190 patients with early age-related macular degeneration, 181 patients with exudative age-related macular degeneration (eAMD), and a random sample of 210 subjects from the general population (control group). The genotyping of rs2108622 was carried out using the real-time polymerase chain reaction method. Results. The analysis of rs2108622 gene polymorphism did not reveal any differences in the distribution of C/C, C/T, and T/T genotypes between the early AMD group, the eAMD group, and the control group. The CYP4F2 (1347C>T) T/T genotype was more frequent in males with eAMD compared to females (10.2% versus 0.8%; p = 0.0052); also T/T genotype was less frequently present in eAMD females compared to healthy control females (0.8% versus 6.2%; p = 0.027). Conclusion. Rs2108622 gene polymorphism had no predominant effect on the development of early AMD and eAMD. The T/T genotype was more frequent in males with eAMD compared to females and less frequently present in eAMD females compared to healthy females.

  7. Macular lutein and zeaxanthin are related to brain lutein and zeaxanthin in primates

    PubMed Central

    Vishwanathan, Rohini; Neuringer, Martha; Snodderly, D. Max; Schalch, Wolfgang; Johnson, Elizabeth J.

    2013-01-01

    Objectives Xanthophyll pigments lutein and zeaxanthin cross the blood-retina barrier to preferentially accumulate in the macular region of the neural retina. There they form macular pigment, protecting the retina from blue light damage and oxidative stress. Lutein and zeaxanthin also accumulate in brain tissue. The objective of the study was to evaluate the relationship between retinal and brain levels of these xanthophylls in non-human primates. Methods Study animals included rhesus monkeys reared on diets devoid of xanthophylls that were subsequently fed pure lutein or pure zeaxanthin (both at 3.9 μmol/kg*d, n=6/group) and normal rhesus monkeys fed a stock diet (0.26 μmol/kg*d lutein and 0.24 μmol/kg*d zeaxanthin, n=5). Retina (4 mm macular punch, 4-8 mm annulus and periphery) and brain tissue (cerebellum, frontal cortex, occipital cortex and pons) from the same animals were analyzed by reverse phase HPLC. Results Lutein in the macula and annulus were significantly related to lutein levels in the cerebellum, occipital cortex and pons, both in bivariate analysis and after adjusting for age, sex and n–3 fatty acid status. In the frontal cortex the relationship was marginally significant. Macular zeaxanthin was significantly related to zeaxanthin in the cerebellum and frontal cortex, while the relationship was marginally significant in the occipital cortex and pons in a bivariate model. Discussion An integrated measure of total macular pigment optical density, which can be measured noninvasively, has the potential to be used as a biomarker to assess brain lutein and zeaxanthin status. PMID:22780947

  8. CYP4F2 (rs2108622) Gene Polymorphism Association with Age-Related Macular Degeneration

    PubMed Central

    Kriauciuniene, Loresa; Balciuniene, Vilma Jurate; Buteikiene, Dovile; Miniauskiene, Goda; Liutkeviciene, Rasa

    2016-01-01

    Background. Age-related macular degeneration is the leading cause of blindness in elderly individuals where aetiology and pathophysiology of age-related macular degeneration are not absolutely clear. Purpose. To determine the frequency of the genotype of rs2108622 in patients with early and exudative age-related macular degeneration. Methods. The study enrolled 190 patients with early age-related macular degeneration, 181 patients with exudative age-related macular degeneration (eAMD), and a random sample of 210 subjects from the general population (control group). The genotyping of rs2108622 was carried out using the real-time polymerase chain reaction method. Results. The analysis of rs2108622 gene polymorphism did not reveal any differences in the distribution of C/C, C/T, and T/T genotypes between the early AMD group, the eAMD group, and the control group. The CYP4F2 (1347C>T) T/T genotype was more frequent in males with eAMD compared to females (10.2% versus 0.8%; p = 0.0052); also T/T genotype was less frequently present in eAMD females compared to healthy control females (0.8% versus 6.2%; p = 0.027). Conclusion. Rs2108622 gene polymorphism had no predominant effect on the development of early AMD and eAMD. The T/T genotype was more frequent in males with eAMD compared to females and less frequently present in eAMD females compared to healthy females. PMID:27652291

  9. Merging Black Holes

    NASA Technical Reports Server (NTRS)

    Centrella, Joan; Baker, John G.; Kelly, Bernard J.; vanMeter, James R.

    2010-01-01

    Black-hole mergers take place in regions of very strong and dynamical gravitational fields, and are among the strongest sources of gravitational radiation. Probing these mergers requires solving the full set of Einstein's equations of general relativity numerically. For more than 40 years, progress towards this goal has been very slow, as numerical relativists encountered a host of difficult problems. Recently, several breakthroughs have led to dramatic progress, enabling stable and accurate calculations of black-hole mergers. This article presents an overview of this field, including impacts on astrophysics and applications in gravitational wave data analysis.

  10. Characterizing Black Hole Mergers

    NASA Technical Reports Server (NTRS)

    Baker, John; Boggs, William Darian; Kelly, Bernard

    2010-01-01

    Binary black hole mergers are a promising source of gravitational waves for interferometric gravitational wave detectors. Recent advances in numerical relativity have revealed the predictions of General Relativity for the strong burst of radiation generated in the final moments of binary coalescence. We explore features in the merger radiation which characterize the final moments of merger and ringdown. Interpreting the waveforms in terms of an rotating implicit radiation source allows a unified phenomenological description of the system from inspiral through ringdown. Common features in the waveforms allow quantitative description of the merger signal which may provide insights for observations large-mass black hole binaries.

  11. Infinitely coloured black holes

    NASA Astrophysics Data System (ADS)

    Mavromatos, Nick E.; Winstanley, Elizabeth

    2000-04-01

    We formulate the field equations for SU (icons/Journals/Common/infty" ALT="infty" ALIGN="TOP"/> ) Einstein-Yang-Mills theory, and use an analytic approximation to elucidate the properties of spherically symmetric black hole solutions. This model may be motivated by string theory considerations, given the enormous gauge symmetries which characterize string theory. The solutions simplify considerably in the presence of a negative cosmological constant, particularly for the limiting cases of a very large cosmological constant or very small gauge field. The black holes possess infinite amounts of gauge field hair, and we speculate on possible consequences of this for quantum decoherence, which, however, we do not tackle here.

  12. Euclidean black hole vortices

    NASA Technical Reports Server (NTRS)

    Dowker, Fay; Gregory, Ruth; Traschen, Jennie

    1991-01-01

    We argue the existence of solutions of the Euclidean Einstein equations that correspond to a vortex sitting at the horizon of a black hole. We find the asymptotic behaviors, at the horizon and at infinity, of vortex solutions for the gauge and scalar fields in an abelian Higgs model on a Euclidean Schwarzschild background and interpolate between them by integrating the equations numerically. Calculating the backreaction shows that the effect of the vortex is to cut a slice out of the Schwarzschild geometry. Consequences of these solutions for black hole thermodynamics are discussed.

  13. Tunnelling from black holes and tunnelling into white holes

    NASA Astrophysics Data System (ADS)

    Chatterjee, Bhramar; Ghosh, A.; Mitra, P.

    2008-03-01

    Hawking radiation is nowadays being understood as tunnelling through black hole horizons. Here, the extension of the Hamilton-Jacobi approach to tunnelling for non-rotating and rotating black holes in different non-singular coordinate systems not only confirms this quantum emission from black holes but also reveals the new phenomenon of absorption into white holes by quantum mechanical tunnelling. The rôle of a boundary condition of total absorption or emission is also clarified.

  14. When Black Holes Collide

    NASA Technical Reports Server (NTRS)

    Baker, John

    2010-01-01

    Among the fascinating phenomena predicted by General Relativity, Einstein's theory of gravity, black holes and gravitational waves, are particularly important in astronomy. Though once viewed as a mathematical oddity, black holes are now recognized as the central engines of many of astronomy's most energetic cataclysms. Gravitational waves, though weakly interacting with ordinary matter, may be observed with new gravitational wave telescopes, opening a new window to the universe. These observations promise a direct view of the strong gravitational dynamics involving dense, often dark objects, such as black holes. The most powerful of these events may be merger of two colliding black holes. Though dark, these mergers may briefly release more energy that all the stars in the visible universe, in gravitational waves. General relativity makes precise predictions for the gravitational-wave signatures of these events, predictions which we can now calculate with the aid of supercomputer simulations. These results provide a foundation for interpreting expect observations in the emerging field of gravitational wave astronomy.

  15. Hot-hole photodetectors

    NASA Astrophysics Data System (ADS)

    2014-05-01

    By injecting high-energy charge carriers (dubbed 'hot holes') into a semiconductor, scientists have succeeded in realizing photodetectors capable of detecting ultralong wavelengths. Unil Perera from Georgia State University in the USA explains how the devices work and how they can be improved.

  16. Drilling Square Holes.

    ERIC Educational Resources Information Center

    Smith, Scott G.

    1993-01-01

    A Reuleaux triangle is constructed by drawing an arc connecting each pair of vertices of an equilateral triangle with radius equal to the side of the triangle. Investigates the application of drilling a square hole using a drill bit in the shape of a Reuleaux triangle. (MDH)

  17. Laser bottom hole assembly

    DOEpatents

    Underwood, Lance D; Norton, Ryan J; McKay, Ryan P; Mesnard, David R; Fraze, Jason D; Zediker, Mark S; Faircloth, Brian O

    2014-01-14

    There is provided for laser bottom hole assembly for providing a high power laser beam having greater than 5 kW of power for a laser mechanical drilling process to advance a borehole. This assembly utilizes a reverse Moineau motor type power section and provides a self-regulating system that addresses fluid flows relating to motive force, cooling and removal of cuttings.

  18. Moulting Black Holes

    NASA Astrophysics Data System (ADS)

    Bena, Iosif; Chowdhury, Borun D.; de Boer, Jan; El-Showk, Sheer; Shigemori, Masaki

    2012-03-01

    We find a family of novel supersymmetric phases of the D1-D5 CFT, which in certain ranges of charges have more entropy than all known ensembles. We also find bulk BPS configurations that exist in the same range of parameters as these phases, and have more entropy than a BMPV black hole; they can be thought of as coming from a BMPV black hole shedding a "hair" condensate outside of the horizon. The entropy of the bulk configurations is smaller than that of the CFT phases, which indicates that some of the CFT states are lifted at strong coupling. Neither the bulk nor the boundary phases are captured by the elliptic genus, which makes the coincidence of the phase boundaries particularly remarkable. Our configurations are supersymmetric, have non-Cardy-like entropy, and are the first instance of a black hole entropy enigma with a controlled CFT dual. Furthermore, contrary to common lore, these objects exist in a region of parameter space (between the "cosmic censorship bound" and the "unitarity bound") where no black holes were thought to exist.

  19. The Antarctic Ozone Hole.

    ERIC Educational Resources Information Center

    Stolarski, Richard S.

    1988-01-01

    Discusses the Airborne Antarctic Ozone Experiment (1987) and the findings of the British Antarctic Survey (1985). Proposes two theories for the appearance of the hole in the ozone layer over Antarctica which appears each spring; air pollution and natural atmospheric shifts. Illustrates the mechanics of both. Supports worldwide chlorofluorocarbon…

  20. Black hole magnetospheres

    SciTech Connect

    Nathanail, Antonios; Contopoulos, Ioannis

    2014-06-20

    We investigate the structure of the steady-state force-free magnetosphere around a Kerr black hole in various astrophysical settings. The solution Ψ(r, θ) depends on the distributions of the magnetic field line angular velocity ω(Ψ) and the poloidal electric current I(Ψ). These are obtained self-consistently as eigenfunctions that allow the solution to smoothly cross the two singular surfaces of the problem, the inner light surface inside the ergosphere, and the outer light surface, which is the generalization of the pulsar light cylinder. Magnetic field configurations that cross both singular surfaces (e.g., monopole, paraboloidal) are uniquely determined. Configurations that cross only one light surface (e.g., the artificial case of a rotating black hole embedded in a vertical magnetic field) are degenerate. We show that, similar to pulsars, black hole magnetospheres naturally develop an electric current sheet that potentially plays a very important role in the dissipation of black hole rotational energy and in the emission of high-energy radiation.

  1. "Holes": Folklore Redux.

    ERIC Educational Resources Information Center

    Mascia, Elizabeth G.

    2001-01-01

    Demonstrates that a careful reading of the book for young adults, "Holes" by Louis Sachar, reveals how this contemporary story is grounded in folklore, and that it is this debt to folk literature that allows readers to accept an improbable plot. Shows how the story weaves together elements from traditional folk literature and stretches them across…

  2. Roof bolt hole groover

    SciTech Connect

    Not Available

    1985-11-05

    A hole groover comprising a pair of grooving bits radially protruding from the surface of a drill rod and connected to swivel upwardly and downwardly near the end of the drill rod where the drill bit is connected. A connecting rod is connected to the inside ends of the groove bits and causes arcuate movement of the grooving bits as it reciprocates. The hole groover further includes a gear box which is connectable to a rotary drilling unit which converts rotational movement of the rotary drill until to reciprocating movement of a lever. The lever is connected to the connecting rod which causes movement of the grooving bits. The device is readily adaptable to be connected to most rotary drill units and the depth and intervals of the grooves can be easily controlled by adjusting the length of the grooving bits and the gear ratios. The device enables grooves to be cut in a wall hole surface, concurrently with the drilling of the hole.

  3. Aspects of hairy black holes

    SciTech Connect

    Anabalón, Andrés; Astefanesei, Dumitru

    2015-03-26

    We review the existence of exact hairy black holes in asymptotically flat, anti-de Sitter and de Sitter space-times. We briefly discuss the issue of stability and the charging of the black holes with a Maxwell field.

  4. The relationship between foveal short-wavelength-sensitive visual function and macular pigment optical density in the ageing age.

    PubMed

    Beirne, Raymond O

    2013-06-28

    To investigate the role of macular pigment in preserving foveal short-wavelength-sensitive (SWS) visual function in the ageing eye orientation identification acuity was measured in the fovea and at 12° eccentricity (nasal visual field) under SWS-cone isolating conditions in 73 participants (aged 20-71). Macular pigment optical density (MPOD) was measured at 0.5° eccentricity from the foveal centre using a heterochromatic flicker photometry (HFP) based instrument. MPOD was not significantly related to age but reduced SWS orientation identification acuity was associated with increasing age in the fovea and at 12° eccentricity. The rate at which foveal acuity changed in relation to acuity at 12° with increasing age was not significantly related to macular pigment levels. These findings do not support the hypothesis that higher macular pigment levels protect S-cone mediated foveal visual function in the ageing eye. PMID:23591086

  5. Slowly balding black holes

    NASA Astrophysics Data System (ADS)

    Lyutikov, Maxim; McKinney, Jonathan C.

    2011-10-01

    The “no-hair” theorem, a key result in general relativity, states that an isolated black hole is defined by only three parameters: mass, angular momentum, and electric charge; this asymptotic state is reached on a light-crossing time scale. We find that the no-hair theorem is not formally applicable for black holes formed from the collapse of a rotating neutron star. Rotating neutron stars can self-produce particles via vacuum breakdown forming a highly conducting plasma magnetosphere such that magnetic field lines are effectively “frozen in” the star both before and during collapse. In the limit of no resistivity, this introduces a topological constraint which prohibits the magnetic field from sliding off the newly-formed event horizon. As a result, during collapse of a neutron star into a black hole, the latter conserves the number of magnetic flux tubes NB=eΦ∞/(πcℏ), where Φ∞≈2π2BNSRNS3/(PNSc) is the initial magnetic flux through the hemispheres of the progenitor and out to infinity. We test this theoretical result via 3-dimensional general relativistic plasma simulations of rotating black holes that start with a neutron star dipole magnetic field with no currents initially present outside the event horizon. The black hole’s magnetosphere subsequently relaxes to the split-monopole magnetic field geometry with self-generated currents outside the event horizon. The dissipation of the resulting equatorial current sheet leads to a slow loss of the anchored flux tubes, a process that balds the black hole on long resistive time scales rather than the short light-crossing time scales expected from the vacuum no-hair theorem.

  6. Macular edema in underserved diabetic patients: Improving detection by enhancing the optical signature and data analysis techniques

    NASA Astrophysics Data System (ADS)

    Alhamami, Mastour Abdullah

    Diabetic retinopathy and diabetic macular edema are chief causes of vision loss in working adults. Thus, retinal screening of patients with diabetes has become standard practice in some countries to prevent visual impairment and blindness from diabetic retinopathy. One goal is to improve techniques currently used to diagnose diabetic retinopathy. Another goal is to probe pathophysiological changes seen with imaging methods. Analysis was performed on a novel dataset from more than 2000 underserved adult diabetic patients, who were recruited for a screening study for diabetic eye disease. Data were collected from four county clinics at Alameda Health, Alameda County, CA. Over 90% of patients self-identified as a racial/ethnic identity other than non-Hispanic white. We investigated the prevalence and optical properties of macular edema. In the first study, a retrospective cohort study was performed to compare macular thickness in diabetic patients with and without macular edema to determine the presence of damage to the external limiting membrane or and the relation of damage to the ELM to damage to photoreceptors. In the second study, we investigated whether the information in red light better visualizes cysts in diabetic macular edema, as compared to green light. In the third study, we investigated whether the demographic and blood glucose information predict diabetic macular edema. Three logistic regression analyses were compared. In the fourth study, we examined how different outcome measures of retinal thickness vary with demographic and blood glucose measures, using a trichotomous variable for retinal thickness. The findings point strongly to large individual differences in the development of macular edema, which is difficult to diagnose with the most common methods in dark eyes. Further, while blood glucose was found to be important, there are additional differences in the potential for macular edema that are associated with ethnic group and gender.

  7. Devils Hole, Nevada: revisited

    NASA Astrophysics Data System (ADS)

    Spötl, C.; Dublyansky, Y.

    2012-04-01

    Among the ever increasing number of caves visited and studied by paleoclimate scientists around the globe one site is special for a number of reasons. First described in the literature in 1988, Devils Hole is a geometrically simple cave developed along an extensional fracture in the Amargosa Desert of SW Nevada. The deeper portion of this cavity is phreatic and part of a regional aquifer whose lowest discharge point is Death Valley. Landmark studies by Ike Winograd's team examined thick calcite crusts present on the walls of this and a neighboring cave (termed Devils Hole #2) and retrieved one of the most remarkable (and thought-provoking) isotope proxy records covering the last half million of years (1992). More recently, Coplen (2007) scrutinized the stable isotope systematics at Devils Hole. His results suggest that this setting represents a rare example of inorganic calcite precipitation essentially at isotopic equilibrium. We obtained permission from the Death Valley National Park Service to study and sample Devils Hole #2. While previous studies were based on samples from the phreatic zone we cored the calcite crust just above the groundwater table in an attempt to extend the original record further back in time and to obtain direct paleowater isotope data. Stable isotope data obtained along one core show a very high degree of similarity with the published DH11 core and a first set of U-series dates confirms the stratigraphy down to 476 ka. Older calcite also shows glacial-interglacial oscillations in both carbon and oxygen isotopes. A tentative correlation with Antarctic and deep-sea isotope records suggests that the lower part of the calcite is ca. 800 ka old (i.e. MIS 20). The cores show petrographic evidence of falling groundwater levels during MIS 9, 7 and 5e, but there are no indications of major hiati. Interestingly, growth at our drill location ended shortly after 20 ka BP, i.e. much later than at the subaqueous site in Devils Hole proper where DH11

  8. Effect of treatment of rectal cancer metastasis with intravitreal bevacizumab (Avastin) in patient with subretinal fluid and macular oedema: short-term follow-up.

    PubMed

    Boss, Joseph Daniel; Lieu, Philip; Tewari, Asheesh

    2016-01-01

    We describe the management of subretinal fluid and macular oedema due to colorectal cancer metastasis to the choroid using intravitreal bevacizumab. A patient with grade VI KRAS mutation rectal cancer with metastasis to the lung and cerebellum presented with left eye choroidal metastasis 1 week after being started on the experimental medication KTN3379. After intravitreal bevacizumab administration, the patient had improvement in macular subretinal fluid, but eventually progressed to severe cystoid macular oedema despite monthly intravitreal bevacizumab treatment. PMID:27591037

  9. The utility of using customized heterochromatic flicker photometry (cHFP) to measure macular pigment in patients with age-related macular degeneration.

    PubMed

    Stringham, J M; Hammond, B R; Nolan, J M; Wooten, B R; Mammen, A; Smollon, W; Snodderly, D M

    2008-11-01

    The purpose of this study was to assess the utility and validity of using customized heterochromatic flicker photometry (cHFP) to measure macular pigment optical density (MPOD) in patients with intermediate stages of age-related macular degeneration (AMD). The measurement procedure was optimized to accommodate individual differences in temporal vision related to age, disease, or other factors. The validity criteria were based on the similarity of the spectral absorption curves to ex vivo curves of lutein and zeaxanthin and the similarity of spatial density profiles to those measured in subjects without retinal disease. Macular pigment optical density (MPOD) spatial profiles were measured with an LED-based macular densitometer; spectral absorption curves were measured with a 3-channel Maxwellian view system including a monochromator. All patients were characterized via clinical exams and all but 2 subjects from whom data were obtained had masked grading of color fundus photographs using the Wisconsin Age-Related Maculopathy Grading System. Most of the patients were in AREDS category 2 (27%) or 3 (57%). Patients with visual acuity as poor as 20/80 were included, and could perform the task as long as they could see the stimulus. Eighty-one percent of the patients screened were able to perform the cHFP task, and data were obtained from 30 AMD patients. Spatial profiles of MPOD were measured in 19 subjects who could see the stimulus at all tested loci. These profiles were highly similar to those that have been measured with HFP in subjects without retinal disease. The average shape of the spectral absorption curves for the AMD subjects corresponded well to an ex vivo template. These data support both the utility and validity of the cHFP method for measuring MPOD in subjects with intermediate stages of AMD. The ability to measure the retinal response to nutritional intervention is of practical importance for monitoring patients being supplemented with lutein and

  10. Interplanetary magnetic holes - Theory

    NASA Technical Reports Server (NTRS)

    Burlaga, L. F.; Lemaire, J. F.

    1978-01-01

    Magnetic holes in the interplanetary medium are explained as stationary nonpropagating equilibrium structures in which there are field-aligned enhancements of the plasma density and/or temperature. Magnetic antiholes are considered to be associated with depressions in the plasma pressure. In this model the observed changes in the magnetic field intensity and direction are due to diamagnetic currents that are carried by ions which drift in a sheath as the result of gradients in the magnetic field and in the plasma pressure within the sheath. The thickness of the sheaths that we consider is approximately a few ion Larmor radii. An electric field is normal to the magnetic field in the sheath. Solutions of Vlasov's equation and Maxwell's equations are presented which account for several types of magnetic holes, including 'null sheets,' that have been observed.

  11. Black Holes and Firewalls

    NASA Astrophysics Data System (ADS)

    Polchinski, Joseph

    2015-04-01

    Our modern understanding of space, time, matter, and even reality itself arose from the three great revolutions of the early twentieth century: special relativity, general relativity, and quantum mechanics. But a century later, this work is unfinished. Many deep connections have been discovered, but the full form of a unified theory incorporating all three principles is not known. Thought experiments and paradoxes have often played a key role in figuring out how to fit theories together. For the unification of general relativity and quantum mechanics, black holes have been an important arena. I will talk about the quantum mechanics of black holes, the information paradox, and the latest version of this paradox, the firewall. The firewall points to a conflict between our current theories of spacetime and of quantum mechanics. It may lead to a new understanding of how these are connected, perhaps based on quantum entanglement.

  12. The Antarctic ozone hole

    NASA Technical Reports Server (NTRS)

    Stolarski, Richard S.

    1988-01-01

    Processes that may be responsible for the thinning in the ozone layer above the South Pole are described. The chlorine catalytic cycle which destroys ozone is described, as are the major types of reactions that are believed to interfere with this cycle by forming chlorine reservoirs. The suspected contributions of polar stratospheric clouds to these processes are examined. Finally, the possibility that the ozone hole may be due more to a shift in atmospheric dynamics than to chemical destruction is addressed.

  13. Safety and Tolerability Study of AAV2-sFLT01 in Patients With Neovascular Age-Related Macular Degeneration (AMD)

    ClinicalTrials.gov

    2016-10-20

    Macular Degeneration; Age-Related Maculopathies; Age-Related Maculopathy; Maculopathies, Age-Related; Maculopathy, Age-Related; Retinal Degeneration; Retinal Neovascularization; Gene Therapy; Therapy, Gene; Eye Diseases

  14. Intravitreal bevacizumab role in the treatment of macular edema secondary to retinal vasoproliferative tumor in a patient with neurofibromatosis type 1

    PubMed Central

    Nourinia, Ramin; Motevasseli, Tahmineh; Tofighi, Zahra

    2016-01-01

    Objective: To report a case of neurofibromatosis-1 (NF-1) with retinal vasoproliferative tumor (RVPT) and macular edema and exudation that was successfully treated with intravitreal bevacizumab (IVB). Method: A retrospective case report of patient with neurofibromatosis, retinal vasoproliferative tumor and macular edema who received three monthly intravitreal injections of bevacizumab. Optical coherence tomography (OCT) and fluorescein angiography (FAG) before and three months after treatment were done. Results: Macular edema and exudation of the right eye was effectively resolved with IVB injection and vascularity of RVPT significantly decreased after treatment with IVB. Conclusion: Macular edema and exudation secondary to RVPT in patients with NF-1 could be successfully treated with IVB. PMID:27703870

  15. Rocky Mountain Spotted Fever as a cause of macular star figure.

    PubMed

    Vaphiades, Michael S

    2003-12-01

    An 86-year-old woman with a history of tick bites in the previous months developed subnormal visual acuity in both eyes, keratic precipitates, anterior chamber and vitreous cells, optic disc edema, retinal hemorrhages, and retinal arteriolar sheathing. She had no fever or skin rash. Three weeks later, binocular macular star figures appeared. Brain imaging was negative; cerebrospinal fluid disclosed a lymphocytic pleocytosis and elevated protein. The serum Rickettsia rickettsii antibody test was markedly positive, establishing a diagnosis of Rocky Mountain Spotted Fever (RMSF) as the cause of the ophthalmic findings. Despite treatment with oral doxycycline, these findings improved only modestly. Although neuroretinitis has been previously described in RMSF, macular star has not been documented.

  16. Nanotechnology-based drug delivery treatments and specific targeting therapy for age-related macular degeneration.

    PubMed

    Lin, Tai-Chi; Hung, Kuo-Hsuan; Peng, Chi-Hsien; Liu, Jorn-Hon; Woung, Lin-Chung; Tsai, Ching-Yao; Chen, Shih-Jen; Chen, Yan-Ting; Hsu, Chih-Chien

    2015-11-01

    Nanoparticles combined with cells, drugs, and specially designed genes provide improved therapeutic efficacy in studies and clinical setting, demonstrating a new era of treatment strategy, especially in retinal diseases. Nanotechnology-based drugs can provide an essential platform for sustaining, releasing and a specific targeting design to treat retinal diseases. Poly-lactic-co-glycolic acid is the most widely used biocompatible and biodegradable polymer approved by the Food and Drug Administration. Many studies have attempted to develop special devices for delivering small-molecule drugs, proteins, and other macromolecules consistently and slowly. In this article, we first review current progress in the treatment of age-related macular degeneration. Then, we discuss the function of vascular endothelial growth factor (VEGF) and the pharmacological effects of anti-VEGF-A antibodies and soluble or modified VEGF receptors. Lastly, we summarize the combination of antiangiogenic therapy and nanomedicines, and review current potential targeting therapy in age-related macular degeneration.

  17. Vitrectomy without gas tamponade for macular retinoschisis associated with normal-tension glaucoma.

    PubMed

    Orazbekov, Lukpan; Yasukawa, Tsutomu; Hirano, Yoshio; Ogura, Shuntaro; Usui, Hideaki; Nozaki, Miho; Ogura, Yuichiro

    2015-01-01

    The authors present the case of a patient with normal-tension glaucoma and pit-like maculopathy observed by high-definition optical coherence tomography. Surgical management of macular retinoschisis was associated with improved vision and full resolution of intraretinal fluid and macular detachment. The patient had progressive vision loss over 6 months preoperatively; best corrected visual acuity and high-definition optical coherence tomography changes improved postoperatively. Optic disc pit-like maculopathy can occur in patients with normal-tension glaucoma in the absence of obvious congenital anomalies of the disc. The intraretinal fluid might have migrated from the vitreous cavity through a microhole at the optic disc margin or in the area with the nerve fiber defect. Vitrectomy without gas tamponade might lead to anatomic and functional recovery. Further studies are needed to better understand the pathogenesis of this disease.

  18. Classification of wet aged related macular degeneration using optical coherence tomographic images

    NASA Astrophysics Data System (ADS)

    Haq, Anam; Mir, Fouwad Jamil; Yasin, Ubaid Ullah; Khan, Shoab A.

    2013-12-01

    Wet Age related macular degeneration (AMD) is a type of age related macular degeneration. In order to detect Wet AMD we look for Pigment Epithelium detachment (PED) and fluid filled region caused by choroidal neovascularization (CNV). This form of AMD can cause vision loss if not treated in time. In this article we have proposed an automated system for detection of Wet AMD in Optical coherence tomographic (OCT) images. The proposed system extracts PED and CNV from OCT images using segmentation and morphological operations and then detailed feature set are extracted. These features are then passed on to the classifier for classification. Finally performance measures like accuracy, sensitivity and specificity are calculated and the classifier delivering the maximum performance is selected as a comparison measure. Our system gives higher performance using SVM as compared to other methods.

  19. Age-related macular degeneration and the role of the complement system.

    PubMed

    McHarg, Selina; Clark, Simon J; Day, Anthony J; Bishop, Paul N

    2015-09-01

    Age-related macular degeneration (AMD) is a leading cause of visual impairment. It is characterised by damage to a tissue complex composed of the retinal pigment epithelium, Bruch's membrane and choriocapillaris. In early AMD extracellular debris including drusen accumulates in Bruch's membrane and then in late AMD geographic atrophy and/or neovascularisation develop. Variants in genes encoding components of the alternative pathway of the complement cascade have a major influence on AMD risk, especially at the RCA locus on chromosome 1, which contains CFH and the CFHR genes. Immunohistochemical studies have demonstrated complement components in unaffected and AMD macular tissue. Whilst other factors, including oxidative stress, play important roles in AMD pathogenesis, evidence for the central role played by complement dysregulation is discussed in this review.

  20. Segmentation of the macular choroid in OCT images acquired at 830nm and 1060nm

    NASA Astrophysics Data System (ADS)

    Lee, Sieun; Beg, Mirza F.; Sarunic, Marinko V.

    2013-06-01

    Retinal imaging with optical coherence tomography (OCT) has rapidly advanced in ophthalmic applications with the broad availability of Fourier domain (FD) technology in commercial systems. The high sensitivity afforded by FD-OCT has enabled imaging of the choroid, a layer of blood vessels serving the outer retina. Improved visualization of the choroid and the choroid-sclera boundary has been investigated using techniques such as enhanced depth imaging (EDI), and also with OCT systems operating in the 1060-nm wavelength range. We report on a comparison of imaging the macular choroid with commercial and prototype OCT systems, and present automated 3D segmentation of the choroid-scleral layer using a graph cut algorithm. The thickness of the choroid is an important measurement to investigate for possible correlation with severity, or possibly early diagnosis, of diseases such as age-related macular degeneration.

  1. Stereotactic radiotherapy for wet age-related macular degeneration: current perspectives.

    PubMed

    Neffendorf, James E; Jackson, Timothy L

    2015-01-01

    Neovascular age-related macular degeneration is a leading cause of blindness in the developed world. Currently, the treatment of choice is intravitreal injections of anti-VEGF medications. These require frequent dosing, up to monthly, and impose a substantial burden on patients and the health economy. Ionizing radiation was proposed as a possible treatment for age-related macular degeneration due to its anti-inflammatory and anti-fibrotic properties. Stereotactic radiotherapy is an outpatient-based radiotherapy platform that provides stereotactic application of low energy X-ray to the retina in three highly collimated beams that cross the inferior sclera to overlap at the macula. A randomized, double-masked, sham-controlled trial of 230 patients (INTREPID) showed that a single dose of stereotactic radiotherapy significantly reduces the number of intravitreal anti-VEGF injections needed over 2 years. A larger randomized controlled trial (STAR) is underway. PMID:26491243

  2. Bilateral macular hemorrhage due to megaloblastic anemia: A rare case report.

    PubMed

    Vaggu, Sree Kumar; Bhogadi, Preethi

    2016-02-01

    We report a case of a 17-year-old female patient who presented with sudden, painless, nonprogressive diminished vision in both eyes (best corrected visual acuity in right eye - 6/60 and left eye - 6/36). An ophthalmological evaluation revealed bilateral pale tarsal conjunctiva and bilateral macular hemorrhage. Hematological evaluation revealed the presence of megalocytic anemia (with hemoglobin - 4.9 g%). General examination showed severe pallor. On systemic examination, no abnormality was detected, confirmed by ultrasonography abdomen. Other causes of severe anemia have been ruled out. Intraocular pressure in both eyes was 12 mmHg. This case documents the rare occurrence of bilateral subinternal limiting membrane macular hemorrhage with megaloblastic anemia without thrombocytopenia and other retinal features of anemic retinopathy. PMID:27050355

  3. Bimodal spatial distribution of macular pigment: evidence of a gender relationship

    NASA Astrophysics Data System (ADS)

    Delori, François C.; Goger, Douglas G.; Keilhauer, Claudia; Salvetti, Paola; Staurenghi, Giovanni

    2006-03-01

    The spatial distribution of the optical density of the human macular pigment measured by two-wavelength autofluorescence imaging exhibits in over half of the subjects an annulus of higher density superimposed on a central exponential-like distribution. This annulus is located at about 0.7° from the fovea. Women have broader distributions than men, and they are more likely to exhibit this bimodal distribution. Maxwell's spot reported by subjects matches the measured distribution of their pigment. Evidence that the shape of the foveal depression may be gender related leads us to hypothesize that differences in macular pigment distribution are related to anatomical differences in the shape of the foveal depression.

  4. Genetics and age-related macular degeneration: a practical review for the clinician

    PubMed Central

    Schwartz, Stephen G; Hampton, Blake M; Kovach, Jaclyn L; Brantley, Milam A

    2016-01-01

    Age-related macular degeneration is a complex disease, with both genetic and environmental risk factors interacting in unknown ways. Currently, 52 gene variants within 34 loci have been significantly associated with age-related macular degeneration. Two well-studied major genes are complement factor H (CFH) and age-related maculopathy susceptibility 2 (ARMS2). There exist several commercially available tests that are proposed to stratify patients into high-risk and low-risk groups, as well as predict response to nutritional supplementation. However, at present, the bulk of the available peer-reviewed evidence suggests that genetic testing is more useful as a research tool than for clinical management of patients. PMID:27445455

  5. The use of prisms for vision rehabilitation after macular function loss: an evidence-based review.

    PubMed

    Markowitz, Samuel N; Reyes, Sophia V; Sheng, Li

    2013-05-01

    To determine the efficacy of prisms used for redirection of incoming images towards the peripheral retina in cases with macular function loss. Meta-analysis of published work reporting outcomes from interventions using prisms was performed. The primary outcome measure selected for analysis was visual acuity (VA) used for viewing distance targets. Pooled data from 449 cases where prisms were prescribed for wearing in distance glasses were analysed. Visual acuity was better after using prisms (1.05 versus 0.89 logMAR units, p < 0.044). Mean effect size for improving VA was 79 bigger than the effect size calculated for the control group (0.158 versus 0.002). Most patients (76%) reported compliance with the therapy and also reported other benefits directly derived from the realized VA improvement. Published studies collectively offer positive evidence in support of using prisms for low vision rehabilitation after macular function loss. Further research is required to reach definitive binding conclusions.

  6. What can we learn about age-related macular degeneration from other retinal diseases?

    PubMed

    Zack, D J; Dean, M; Molday, R S; Nathans, J; Redmond, T M; Stone, E M; Swaroop, A; Valle, D; Weber, B H

    1999-11-01

    Age-related macular degeneration (AMD) is increasingly recognized as a complex genetic disorder in which one or more genes contribute to an individual's susceptibility for developing the condition. Twin and family studies as well as population-based genetic epidemiologic methods have convincingly demonstrated the importance of genetics in AMD, though the extent of heritability, the number of genes involved, and the phenotypic and genetic heterogeneity of the condition remain unresolved. The extent to which other hereditary macular dystrophies such as Stargardts disease, familial radial drusen (malattia leventinese), Best's disease, and peripherin/RDS-related dystrophy are related to AMD remains unclear. Alzheimer's disease, another late onset, heterogeneous degenerative disorder of the central nervous system, offers a valuable model for identifying the issues that confront AMD genetics.

  7. Spectral Domain Optical Coherence Tomography Features and Classification Systems for Diabetic Macular Edema: A Review.

    PubMed

    Ruia, Surabhi; Saxena, Sandeep; Gemmy Cheung, Chui Ming; Gilhotra, Jagjit S; Lai, Timothy Y Y

    2016-01-01

    Spectral domain optical coherence tomography (SD-OCT) is fast becoming the current standard of care for the detection and assessment of diabetic macular edema. With the application of SD-OCT for imaging of retinal microstructure and measurement of retinal thickness, new information regarding disease characteristics has been gathered, which was unrecognized previously. Retinal thickness measurements on SD-OCT have also been used for deciding the management and monitoring of the disease. Since its development, OCT has enhanced the understanding of retinal anatomical changes in diabetic retinopathy. Several authors have used SD-OCT to classify diabetic macular edema with the purpose of correlating the pathophysiology with disease severity. The classification systems have helped monitor the treatment efficacy and provide prognostic information on the treatment outcome. The following review article summarizes these classifications. PMID:27632028

  8. Macular telangiectasia type 2 (MacTel) in a 34-year-old patient

    PubMed Central

    Nicolai, Heleen; Wirix, Mieke; Spielberg, Leigh; Leys, Anita

    2014-01-01

    We report macular telangiectasia type 2 (MacTel) in a 34-year-old man, the youngest patient so far published with MacTel type 2. The patient presented with metamorphopsia and impaired reading ability. Diagnosis was based on bilateral abnormal macular autofluorescence, perifoveal telangiectasia with fluorescein angiographic hyperfluorescence without cystoid oedema, a small foveal avascular zone, asymmetric configuration of the foveal pit, disruptions in the inner segment/outer segment layer and hyper-reflective haze and spots in the outer nuclear layer. Although MacTel usually manifests with a slowly progressive decrease in visual acuity in the fifth to seventh decades of life, younger patients may occasionally be diagnosed with the disease. Awareness of subtle signs of the condition is essential for early diagnosis. PMID:25249218

  9. BLACK HOLE AURORA POWERED BY A ROTATING BLACK HOLE

    SciTech Connect

    Takahashi, Masaaki; Takahashi, Rohta

    2010-05-15

    We present a model for high-energy emission sources generated by a standing magnetohydrodynamical (MHD) shock in a black hole magnetosphere. The black hole magnetosphere would be constructed around a black hole with an accretion disk, where a global magnetic field could be originated by currents in the accretion disk and its corona. Such a black hole magnetosphere may be considered as a model for the central engine of active galactic nuclei, some compact X-ray sources, and gamma-ray bursts. The energy sources of the emission from the magnetosphere are the gravitational and electromagnetic energies of magnetized accreting matters and the rotational energy of a rotating black hole. When the MHD shock generates in MHD accretion flows onto the black hole, the plasma's kinetic energy and the black hole's rotational energy can convert to radiative energy. In this Letter, we demonstrate the huge energy output at the shock front by showing negative energy postshock accreting MHD flows for a rapidly rotating black hole. This means that the extracted energy from the black hole can convert to the radiative energy at the MHD shock front. When an axisymmetric shock front is formed, we expect a ring-shaped region with very hot plasma near the black hole; this would look like an 'aurora'. The high-energy radiation generated from there would carry to us the information for the curved spacetime due to the strong gravity.

  10. Perspectives: Black Holes

    NASA Technical Reports Server (NTRS)

    Dolan, Joseph F.; Fisher, Richard R. (Technical Monitor)

    2001-01-01

    When asked to discuss Cyg XR-1, E. E. Salpeter once concluded, 'A black hole in Cyg X(R)-1 is the most conservative hypothesis.' Recent observations now make it likely that a black hole in Cyg XR-1 is the only hypothesis tenable. Chandrasekhar first showed that compact stars - those with the inward force of gravity on their outer layers balanced by the pressure generated by the Pauli exclusion principle acting on its electrons (in white dwarfs) or nucleons (in neutron stars) - have a maximum mass. Equilibrium is achieved at a minimum of the total energy of the star, which is the sum of the positive Fermi energy and the negative gravitational energy. The maximum mass attainable in equilibrium is found by setting E = 0: M(max) = 1.5 M(Sun). If the mass of the star is larger than this, then E can be decreased without bound by decreasing the star's radius and increasing its (negative) gravitational energy. No equilibrium value of the radius exist, and general relativity predicts that gravitational collapse to a point occurs. This point singularity is a black hole.

  11. Intravitreal ziv-aflibercept for macular edema following retinal vein occlusion

    PubMed Central

    Paulose, Remya; Chhablani, Jay; Dedhia, Chintan J; Stewart, Michael W; Mansour, Ahmad M

    2016-01-01

    Aim To report the efficacy of intravitreal ziv-aflibercept injections in eyes with macular edema due to retinal vein occlusions (RVOs). Methods Consecutive patients with persistent or recurrent macular edema (central macula thickness >250 μm) due to RVO were enrolled in this prospective study. Study eyes received intravitreal injections of ziv-aflibercept (1.25 mg/0.05 mL) at baseline. Patients were reassessed monthly for 4 months and given additional injections pro re nata for worsening best-corrected visual acuity (BCVA), intraretinal edema or subretinal fluid seen on spectral domain optical coherence tomography, or central macular thickness (CMT) measurements >250 μm. The primary endpoint was improvement in mean CMT at 4 months. Secondary endpoints included improvement in mean BCVA, and ocular and systemic safety signals. Results Nine eyes (five central and four branch RVOs) of nine patients were enrolled. The mean ± standard deviation CMT decreased from 604±199 μm at baseline to 319±115 μm (P=0.001) at 1 month and to 351±205 μm (P=0.026) at 4 months. The mean BCVA did not improve significantly from baseline (1.00 LogMAR) to the 1-month (0.74 LogMAR; P=0.2) and 4-month (0.71 LogMAR; P=0.13) visits. No safety signals were noted. Conclusion In this small prospective study, intravitreal ziv-aflibercept significantly improved mean CMT in eyes with persistent or recurrent macular edema due to RVOs. Prospective, randomized trials comparing ziv-aflibercept with standard pharmacotherapy are needed to better define efficacy and safety. PMID:27703326

  12. [New perspectives in the approach to age-related macular degeneration].

    PubMed

    Gallego-Pinazo, R; Zapata, M A

    2015-03-01

    The approval of aflibercept for the neovascular form of age-related macular degeneration has opened up the possibility of treating patients with fewer injections, since the drug can be administered once every two months. Aflibercept can also be used as rescue therapy in patients with suboptimal response to other antiangiogenic treatments. The present study reviews the scientific evidence on aflibercept, both in treatment-naïve patients and in those with an unsatisfactory response to conventional treatments. PMID:25925046

  13. Decreased Fixation Stability of the Preferred Retinal Location in Juvenile Macular Degeneration

    PubMed Central

    Bethlehem, Richard A. I.; Dumoulin, Serge O.; Dalmaijer, Edwin S.; Smit, Miranda; Berendschot, Tos T. J. M.; Nijboer, Tanja C. W.; Van der Stigchel, Stefan

    2014-01-01

    Macular degeneration is the main cause for diminished visual acuity in the elderly. The juvenile form of macular degeneration has equally detrimental consequences on foveal vision. To compensate for loss of foveal vision most patients with macular degeneration adopt an eccentric preferred retinal location that takes over tasks normally performed by the healthy fovea. It is unclear however, whether the preferred retinal locus also develops properties typical for foveal vision. Here, we investigated whether the fixation characteristics of the preferred retinal locus resemble those of the healthy fovea. For this purpose, we used the fixation-offset paradigm and tracked eye-position using a high spatial and temporal resolution infrared eye-tracker. The fixation-offset paradigm measures release from fixation under different fixation conditions and has been shown useful to distinguish between foveal and non-foveal fixation. We measured eye-movements in nine healthy age-matched controls and five patients with juvenile macular degeneration. In addition, we performed a simulation with the same task in a group of five healthy controls. Our results show that the preferred retinal locus does not adopt a foveal type of fixation but instead drifts further away from its original fixation and has overall increased fixation instability. Furthermore, the fixation instability is most pronounced in low frequency eye-movements representing a slow drift from fixation. We argue that the increased fixation instability cannot be attributed to fixation under an unnatural angle. Instead, diminished visual acuity in the periphery causes reduced oculomotor control and results in increased fixation instability. PMID:24937090

  14. Local Variability of Macular Thickness Measurements With SD-OCT and Influencing Factors

    PubMed Central

    Miraftabi, Arezoo; Amini, Navid; Gornbein, Jeff; Henry, Sharon; Romero, Pablo; Coleman, Anne L.; Caprioli, Joseph; Nouri-Mahdavi, Kouros

    2016-01-01

    Purpose To compare the intrasession variability of spectral-domain optical coherence tomography (SD-OCT)-derived local macular thickness measures and explore influencing factors. Methods One hundred two glaucomatous eyes (102 patients) and 21 healthy eyes (21 subjects) with three good quality macular images during the same session were enrolled. Thickness measurements were calculated for 3° superpixels for the inner plexiform (IPL), ganglion cell (GCL), or retinal nerve fiber layers (mRNFL), GC/IPL, ganglion cell complex, and full macular thickness. Spatial distribution and magnitude of measurement errors (ME; differences between the 3 individual superpixel values and their mean) and association between MEs and thickness, age, axial length, and image quality were explored. Results MEs had a normal distribution with mostly random noise along with a small fraction of outliers (1.2%–6.6%; highest variability in mRNFL and on the nasal border) based on M-estimation. Boundaries of 95% prediction intervals for variability reached a maximum of 3 μm for all layers and diagnostic groups after exclusion of outliers. Correlation between proportion of outliers and thickness measures varied among various parameters. Age, axial length, or image quality did not influence MEs (P > 0.05 for both groups). Conclusions Local variability of macular SD-OCT measurements is low and uniform across the macula. The relationship between superpixel thickness and outlier proportion varied as a function of the parameter of interest. Translational Relevance Given the low and uniform variability within and across eyes, definition of an individualized ‘variability space' seems unnecessary. The variability measurements from this study could be used for designing algorithms for detection of glaucoma progression. PMID:27486555

  15. Application of multifocal visual evoked potentials in the assessment of visual dysfunction in macular diseases

    PubMed Central

    Jiang, L; Zhang, H; Xie, J; Jiao, X; Zhou, H; Ji, H; Lai, T Y Y; Wang, N

    2011-01-01

    Purpose To evaluate the use of AccuMap multifocal visual evoked potentials (mfVEP) in visual dysfunction caused by macular diseases. Methods Forty-eight eyes with known macular diseases underwent AccuMap mfVEP and microperimetry 1 (MP1) assessments. Evaluation of mfVEP abnormality was based on an amplitude deviation probability plot and the AccuMap Severity Index (ASI). Correlation analyses of the mean mfVEP amplitude corresponding to a radius of 2°, 5°, and 10° of the central visual field, minimum angle of resolution best-corrected visual acuity (BCVA), and MP1 mean sensitivity of the corresponding areas were performed. Results Among the 48 affected eyes, AccuMap mfVEP detected an abnormality of the central visual field in 45 eyes, with a sensitivity of 93.8%. The mean mfVEP amplitudes within a radius of 2°, 5°, and 10° of the central visual field were found to be positively correlated with BCVA (P<0.01 for all groups). The mean amplitudes also positively correlated with the MP1 mean sensitivity value of the corresponding visual field (P<0.01 for all groups). In the group with stable fixation or predominantly central fixation, the mean mfVEP amplitudes did not correlate with the BCVA or the MP1 mean sensitivity value. Regardless of the fixation status, the ASI was found to correlate with both the BCVA and the total MP1 mean defect value. Conclusion Objective perimetry using AccuMap mfVEP might be applied in the assessment of macular function, with the ASI offering a potentially useful indicator for evaluating macular dysfunction. PMID:21720415

  16. Differences in spectral absorption properties between active neovascular macular degeneration and mild age related maculopathy.

    PubMed

    Balaskas, Konstantinos; Nourrit, Vincent; Dinsdale, Michelle; Henson, David B; Aslam, Tariq

    2013-05-01

    This study examines the differences in spectral absorption properties between the maculae of patients with active neovascular macular degeneration and those with early age related maculopathy (ARM). Patients attending for management of neovascular age related macular degeneration (AMD) underwent multispectral imaging with a system comprising of a modified digital fundus camera coupled with a 250-W tungsten-halogen lamp and a liquid crystal fast-tuneable filter. Images were obtained at 8 wavelengths between 496 and 700 nm. Aligned images were used to generate a DLA (differential light absorption, a measure of spectral absorption properties) map of the macular area. DLA maps were generated for both eyes of 10 sequential patients attending for anti-vascular endothelial growth factor injections. Each of these patients had active leaking neovascular AMD in one eye and early ARM or milder disease in the fellow eye. Eyes with neovascular AMD demonstrated lower average levels of DLA compared with their fellow eyes with early ARM (p=0.037, t test). The significant difference in DLA demonstrates the potential of multispectral imaging for differentiating the two pathologies non-invasively. PMID:23137662

  17. Macular pigment and lens optical density measurements-evaluating a flicker machine with novel features

    NASA Astrophysics Data System (ADS)

    Mukherjee, Anirbaan

    Age related macular degeneration (AMD) is one of the leading causes of blindness amongst the elderly. Macular pigment (MP) in the retina has been established to protect individuals against AMD. Improving levels of MP by diet or supplements is the constant quest of clinical practitioners and researchers, thus necessitating development of instruments capable of repeatable and reliable MP measurement. Cataract, a consequence of the rising opacity levels of the lens with age is one of the other major causes of blindness in the world. Mapcatsf, a LED-based microprocessor-controlled heterochromatic flicker photometer (HFP) using photopic vision is capable of measuring the levels of MP and the opacity of the lens in terms of optical density. Test-retest measurements conducted on 83 subjects were analyzed for repeatability in macular pigment optical density (MPOD) measurements. Reliability of the lens optical density (LOD) measurements were tested and compared with those obtained at absolute scotopic thresholds for 25 individuals. A supplement study with 32 individuals both in the young (50) age groups for 6 months further established Mapcatsf's capacity to monitor changing levels of MP in individuals. As an overall outcome, high levels of repeatability and reliability were obtained in MPOD and LOD measurements establishing Mapcatsf as an instrument for use in clinical settings in the future.

  18. The effect of hypoxia upon macular recovery time in normal humans.

    PubMed

    Brinchmann-Hansen, O; Myhre, K

    1989-12-01

    Bright light illumination (photostress) of the macula produces a negative after-image in the form of a central scotoma. The time needed for restoring normal visual acuity function, "macular recovery time," may be measured using a nyctometer. We have measured the recovery in 30 normal men, aged 18 to 23 years, at sea level and at 8,000 ft (n = 10), 15,000 ft (n = 10), and 18,000 ft (n = 10) of simulated altitudes in a low pressure chamber. The degree of initial recovery (the first 30-40 s) was unaffected by hypoxia equivalent to 8,000, 15,000, and 18,000 ft. The recovery at 2 min was impaired by hypoxia at an altitude of 18,000 ft (p = 0.009) but not at 8,000 ft or 15,000 ft. The initial phase of recovery may represent the neural phase of macular function and appears to be more resistant to hypoxia than the recovery at 2 min, the latter probably being dominated by photochemical recovery. The study establishes a critical level of hypoxia where complete recovery of macular sensitivity is not achieved.

  19. Use of Mechanical Turk as a MapReduce Framework for Macular OCT Segmentation.

    PubMed

    Lee, Aaron Y; Lee, Cecilia S; Keane, Pearse A; Tufail, Adnan

    2016-01-01

    Purpose. To evaluate the feasibility of using Mechanical Turk as a massively parallel platform to perform manual segmentations of macular spectral domain optical coherence tomography (SD-OCT) images using a MapReduce framework. Methods. A macular SD-OCT volume of 61 slice images was map-distributed to Amazon Mechanical Turk. Each Human Intelligence Task was set to $0.01 and required the user to draw five lines to outline the sublayers of the retinal OCT image after being shown example images. Each image was submitted twice for segmentation, and interrater reliability was calculated. The interface was created using custom HTML5 and JavaScript code, and data analysis was performed using R. An automated pipeline was developed to handle the map and reduce steps of the framework. Results. More than 93,500 data points were collected using this framework for the 61 images submitted. Pearson's correlation of interrater reliability was 0.995 (p < 0.0001) and coefficient of determination was 0.991. The cost of segmenting the macular volume was $1.21. A total of 22 individual Mechanical Turk users provided segmentations, each completing an average of 5.5 HITs. Each HIT was completed in an average of 4.43 minutes. Conclusions. Amazon Mechanical Turk provides a cost-effective, scalable, high-availability infrastructure for manual segmentation of OCT images. PMID:27293877

  20. Influence of anti-VEGF about cardiovascular biomarkers in age related macular degeneration.

    PubMed

    Manresa, N; Mulero, J; Losada, M; Zafrilla, P

    2015-02-01

    Systemic VEGF inhibition disrupts endothelial homeostasis and accelerates the atherogenesis, suggesting that these events contribute to the clinical cardiovascular adverse events of VEGF-inhibiting therapies. The objective of the current study was to analyze the effect of anti-VEGF therapy on cardiovascular risk factors in patients with exudative age related macular degeneration. A total of 73 patients with exudative age related macular degeneration (without previous anti-VEGF therapy) were treated with two anti-VEGF: Ranibizumab and Pegaptanib sodium. The follow up was 6 months. The following parameters were determined before and after treatment: homocysteine, lipids (total cholesterol, triglycerides, HDL-c, LDL-c), C-Reactive Protein and fibrinogen. There were not statistically significant differences in parameters studied before and after treatment with both Pegaptanib sodium and Ranibizumab, except C-Reactive Protein. Of all patients analyzed, only 3 of them have initially C-Reactive Protein levels above normal levels and after antiangiogenic therapy, there was a significant increase in C-Reactive Protein. We have not found results in our study who to suspect that treatment with anti-VEGF in the patients with exudative age related macular degeneration increases cardiovascular risk predictors. However, after therapy was increased the CRP and fibrinogen may mean that anti-VEGF contribute an alteration of endothelial homeostasis in exudative AMD.

  1. Submacular hemorrhage in neovascular age-related macular degeneration: A synthesis of the literature.

    PubMed

    Stanescu-Segall, Dinu; Balta, Florian; Jackson, Timothy L

    2016-01-01

    Large submacular hemorrhage, an uncommon manifestation of neovascular age-related macular degeneration, may also occur with idiopathic polypoidal choroidal vasculopathy. Submacular hemorrhage damages photoreceptors owing to iron toxicity, fibrin meshwork contraction, and reduced nutrient flux, with subsequent macular scarring. Clinical and experimental studies support prompt treatment, as tissue damage can occur within 24 hours. Without treatment the natural history is poor, with a mean final visual acuity (VA) of 20/1600. Reported treatments include retinal pigment epithelial patch, macular translocation, pneumatic displacement, intravitreal or subretinal tissue plasminogen activator, intravitreal anti-vascular endothelial growth factor (VEGF) drugs, and combinations thereof. In the absence of comparative studies, we combined eligible studies to assess the VA change before and after each treatment option. The greatest improvement occurred after combined pars plana vitrectomy, subretinal tissue plasminogen activator, intravitreal gas, and anti-vascular endothelial growth factor treatment, with VA improving from 20/1000 to 20/400. The best final VA occurred using combined intravitreal tissue plasminogen activator, gas, and anti-vascular endothelial growth factor therapy, with VA improving from 20/200 to 20/100. Both treatments had an acceptable safety profile, but most studies were small, and larger randomized controlled trials are needed to determine both safety and efficacy.

  2. Monoscopic versus stereoscopic photography in screening for clinically significant macular edema.

    PubMed

    Welty, Christopher J; Agarwal, Anita; Merin, Lawrence M; Chomsky, Amy

    2006-01-01

    The purpose of the study was to determine whether monoscopic photography could serve as an accurate tool when used to screen for clinically significant macular edema. In a masked randomized fashion, two readers evaluated monoscopic and stereoscopic retinal photographs of 100 eyes. The photographs were evaluated first individually for probable clinically significant macular edema based on the Early Treatment Diabetic Retinopathy Study criteria and then as stereoscopic pairs. Graders were evaluated for sensitivity and specificity individually and in combination. Individually, reader one had a sensitivity of 0.93 and a specificity of 0.77, and reader two had a sensitivity of 0.88 and a specificity of 0.94. In combination, the readers had a sensitivity of 0.91 and a specificity of 0.86. They correlated on 0.76 of the stereoscopic readings and 0.92 of the monoscopic readings. These results indicate that the use of monoscopic retinal photography may be an accurate screening tool for clinically significant macular edema.

  3. Myopic Macular Retinoschisis in Teenagers: Clinical Characteristics and Spectral Domain Optical Coherence Tomography Findings

    PubMed Central

    Sun, Chuan-bin; You, Yong-sheng; Liu, Zhe; Zheng, Lin-yan; Chen, Pei-qing; Yao, Ke; Xue, An-quan

    2016-01-01

    To investigate the morphological characteristics of myopic macular retinoschisis (MRS) in teenagers with high myopia, six male (9 eyes) and 3 female (4 eyes) teenagers with typical MRS identified from chart review were evaluated. All cases underwent complete ophthalmic examinations including best corrected visual acuity (BCVA), indirect ophthalmoscopy, colour fundus photography, B-type ultrasonography, axial length measurement, and spectral-domain optical coherence tomography (SD-OCT). The average age was 17.8 ± 1.5 years, average refractive error was −17.04 ± 3.04D, average BCVA was 0.43 ± 0.61, and average axial length was 30.42 ± 1.71 mm. Myopic macular degenerative changes (MDC) by colour fundus photographs revealed Ohno-Matsui Category 1 in 4 eyes, and Category 2 in 9 eyes. Posterior staphyloma was found in 9 eyes. SD-OCT showed outer MRS in all 13 eyes, internal limiting membrane detachment in 7 eyes, vascular microfolds in 2 eyes, and inner MRS in 1 eye. No premacular structures such as macular epiretinal membrane or partially detached posterior hyaloids were found. Our results showed that MRS rarely occurred in highly myopic teenagers, and was not accompanied by premacular structures, severe MDC, or even obvious posterior staphyloma. This finding indicates that posterior scleral expansion is probably the main cause of MRS. PMID:27294332

  4. Multimodal retinal imaging of diabetic macular edema: toward new paradigms of pathophysiology.

    PubMed

    Midena, Edoardo; Bini, Silvia

    2016-09-01

    The pathophysiology of diabetic macular edema (DME) is multifactorial and partly still unknown. An increasing body of evidence suggests that neurodegeneration and retinal glial cells activation occur even before the earliest clinical manifestation of diabetic retinal vasculopathy. Nowadays, new non-invasive techniques are available to assess and characterize DME, not only in a quantitative perspective, but also making it possible to understand and quantify the pathogenic processes sustaining fluid accumulation. Optical coherence tomography (OCT) allows documenting not only parameters such as macular volume, central and sectorial retinal thickness, fluid localization, and integrity of retinal layers, but also new still poorly investigated reflectivity aspects. Hyperreflective intraretinal spots (HRS) have been detected on OCT scans through the retinal layers, with a presumptive migration pattern towards the external layers during the occurrence of diabetic retinopathy and DME. These HRS have been hypothesised to represent an in-vivo marker of microglial activation. Autofluorescence of the fundus (FAF) also offers a non-invasive imaging technique of DME. The area of increased FAF correlates with the presence of intraretinal fluid and probably retinal glial activation. Microperimetry allows the measurement of retinal sensitivity by testing specific selected retinal areas. Some studies have shown that increased macular FAF in DME correlates better with visual function assessed with microperimetry than with visual acuity, showing that new imaging and functional techniques may help to elucidate DME pathogenesis and to target therapeutical strategies. PMID:27154296

  5. Intravitreal bevacizumab injections for diabetic macular edema – predictors of response: a retrospective study

    PubMed Central

    Joshi, Lavnish; Bar, Asaf; Tomkins-Netzer, Oren; Yaganti, Satish; Morarji, Jiten; Vouzounis, Panayiotis; Seguin-Greenstein, Sophie; Taylor, Simon R; Lightman, Sue

    2016-01-01

    Background Outcomes of intravitreal antivascular endothelial growth factor injections are variable among patients with diabetic macular edema (DME). The aim of this study was to determine the ocular and systemic predictors of DME response to intravitreal bevacizumab (IVB). Methods Retrospective review over 2 years of 78 eyes from 54 patients. An anatomical response to IVB was defined as a 20% reduction in central macula thickness after the first course (three injections) of IVB. Results Twenty-eight percent of patients had an anatomical response after the first course of IVB. Systemic hypertension (odds ratio, 95% confidence interval: 12.1, 0.7–21) was a statistically significant predictor (P=0.025) of a good response to IVB, whereas previous macular laser was a statistically significant (P=0.0005) predictor of a poor response (0.07, 0.01–0.32). Sixty-eight percent of eyes underwent subsequent treatment for DME after the first course of IVB. The visual acuity gain at 24 months in hypertensive (0.7±3.6 letters) and nonhypertensive (5.2±3.7 letters) patients was not significantly different (P=0.41). Conclusion Hypertension and previous macular laser were positive and negative predictors of response to IVB, respectively. However, long-term visual acuity changes were not significantly different between eyes with and without systemic hypertension. PMID:27799737

  6. Prevalence and patterns of comorbid cognitive impairment in low vision rehabilitation (LVR) for macular disease

    PubMed Central

    Whitson, Heather E.; Ansah, Deidra; Whitaker, Diane; Potter, Guy; Cousins, Scott W.; MacDonald, Heather; Pieper, Carl F.; Landerman, Lawrence; Steffens, David C.; Cohen, Harvey J.

    2009-01-01

    The prevalence of comorbid cognitive impairment among older adults referred to LVR for macular disease is unknown. We performed cognitive testing on 101 adults aged 65 years or older with macular disease who were referred to The Duke LVR Clinic between September 2007 and March 2008. Scores on the telephone interview for cognitive status-modified (TICS-m) ranged from 7 to 44, with 18.8% of scores below an established cutoff for cognitive impairment (≤ 27) and an additional 27.7% of scores considered marginal (28-30). On letter fluency, 46% of participants scored at least 1 × S.D. below the mean for their age, gender, race, and education level, and 18% of participants scored at least 2 × S.D. below their demographic mean. On logical memory, 26% of participants scored at least 1 × S.D. below the mean for their age group and race and 6% scored at least 2 × S.D. below their demographic mean. High prevalence of cognitive impairment, with particular difficulty in verbal fluency and verbal memory, may compromise the success of low vision rehabilitation interventions among macular disease patients. Additional work is needed to develop strategies to maximize function in older adults with this common comorbidity. PMID:19427045

  7. A case of Mac Tel 2 with an unusual sub macular vitelliform lesion

    PubMed Central

    Lekha, T.; Sarwate, Nikit; Sarwate, Renuka

    2015-01-01

    Method: Observational case report describing the clinical, FFA, OCT and mfERG findings in an elderly female patient with atypical features of macular telangiectasia (Mac Tel 2) Results: A 71-year-old lady was detected to have characteristic features of Mac Tel 2 in the left eye (LE) and a yellowish sub macular vitelliform like lesion in the right eye (RE). FFA showed ill defined hyper fluorescence in the RE and telangiectasia and parafoveal leakage typical of Mac Tel 2 in the LE. On OCT RE had hyper reflective clump of echoes subfoveally with an intact RPE and LE had foveal thinning with hypo reflective intraretinal cavities. mfERG responses were normal in the RE and reduced in the LE. During the course of 3 years LE showed natural progression while RE remained unchanged. Conclusion: Structural and functional evaluation of an unusual sub macular vitelliform lesion seen in association with Mac Tel 2 and its course over a period of 3 years is described. The differentiating features of this lesion from adult onset foveomacular vitelliform dystrophy (AFMD) are discussed.

  8. Perspective on the role of Ozurdex (dexamethasone intravitreal implant) in the management of diabetic macular oedema

    PubMed Central

    Mehta, Hemal; Gillies, Mark

    2015-01-01

    Diabetic macular oedema (DMO) is the most common cause of visual loss in the working age population. Intravitreal therapy has superseded macular laser as the first-line treatment for the management of centre-involving DMO in most patients. As well as the proven efficacy of intravitreal anti-vascular endothelial growth factor (anti-VEGF) agents, phase II and III clinical trials of Ozurdex intravitreal dexamethasone implants for DMO have also demonstrated a mean increase in visual acuity and corresponding mean reduction in central macular thickness, particularly in pseudophakic eyes. Because of the risk of visual loss from cataract, glaucoma and intraocular infection with the use of intravitreal steroids, Ozurdex tends to be reserved for use in patients unresponsive to anti-VEGF therapy for centre-involving DMO. Situations where Ozurdex may be considered a first-line treatment option for eyes with centre-involving DMO include pseudophakia, impending cataract surgery, or in the context of a recent arterial thromboembolic event. Because of their stable pharmacokinetics, Ozurdex slow-release implants may also be considered in vitrectomized eyes. PMID:26336592

  9. Use of Mechanical Turk as a MapReduce Framework for Macular OCT Segmentation

    PubMed Central

    Lee, Aaron Y.; Lee, Cecilia S.; Keane, Pearse A.; Tufail, Adnan

    2016-01-01

    Purpose. To evaluate the feasibility of using Mechanical Turk as a massively parallel platform to perform manual segmentations of macular spectral domain optical coherence tomography (SD-OCT) images using a MapReduce framework. Methods. A macular SD-OCT volume of 61 slice images was map-distributed to Amazon Mechanical Turk. Each Human Intelligence Task was set to $0.01 and required the user to draw five lines to outline the sublayers of the retinal OCT image after being shown example images. Each image was submitted twice for segmentation, and interrater reliability was calculated. The interface was created using custom HTML5 and JavaScript code, and data analysis was performed using R. An automated pipeline was developed to handle the map and reduce steps of the framework. Results. More than 93,500 data points were collected using this framework for the 61 images submitted. Pearson's correlation of interrater reliability was 0.995 (p < 0.0001) and coefficient of determination was 0.991. The cost of segmenting the macular volume was $1.21. A total of 22 individual Mechanical Turk users provided segmentations, each completing an average of 5.5 HITs. Each HIT was completed in an average of 4.43 minutes. Conclusions. Amazon Mechanical Turk provides a cost-effective, scalable, high-availability infrastructure for manual segmentation of OCT images. PMID:27293877

  10. Myopic Macular Retinoschisis in Teenagers: Clinical Characteristics and Spectral Domain Optical Coherence Tomography Findings.

    PubMed

    Sun, Chuan-Bin; You, Yong-Sheng; Liu, Zhe; Zheng, Lin-Yan; Chen, Pei-Qing; Yao, Ke; Xue, An-Quan

    2016-01-01

    To investigate the morphological characteristics of myopic macular retinoschisis (MRS) in teenagers with high myopia, six male (9 eyes) and 3 female (4 eyes) teenagers with typical MRS identified from chart review were evaluated. All cases underwent complete ophthalmic examinations including best corrected visual acuity (BCVA), indirect ophthalmoscopy, colour fundus photography, B-type ultrasonography, axial length measurement, and spectral-domain optical coherence tomography (SD-OCT). The average age was 17.8 ± 1.5 years, average refractive error was -17.04 ± 3.04D, average BCVA was 0.43 ± 0.61, and average axial length was 30.42 ± 1.71 mm. Myopic macular degenerative changes (MDC) by colour fundus photographs revealed Ohno-Matsui Category 1 in 4 eyes, and Category 2 in 9 eyes. Posterior staphyloma was found in 9 eyes. SD-OCT showed outer MRS in all 13 eyes, internal limiting membrane detachment in 7 eyes, vascular microfolds in 2 eyes, and inner MRS in 1 eye. No premacular structures such as macular epiretinal membrane or partially detached posterior hyaloids were found. Our results showed that MRS rarely occurred in highly myopic teenagers, and was not accompanied by premacular structures, severe MDC, or even obvious posterior staphyloma. This finding indicates that posterior scleral expansion is probably the main cause of MRS. PMID:27294332

  11. Automated segmentation of intraretinal layers from spectral-domain macular OCT: reproducibility of layer thickness measurements

    NASA Astrophysics Data System (ADS)

    Lee, Kyungmoo; Abràmoff, Michael D.; Sonka, Milan; Garvin, Mona K.

    2011-03-01

    Changes in intraretinal layer thickness occur in a variety of diseases such as glaucoma, macular edema and diabetes. To segment the intraretinal layers from macular spectral-domain OCT (SD-OCT) scans, we previously introduced an automated multiscale 3-D graph search method and validated its performance by computing unsigned border positioning differences when compared with human expert tracings. However, it is also important to study the reproducibility of resulting layer thickness measurements, as layer thickness is a commonly used clinical parameter. In this work, twenty eight (14 x 2) repeated macular OCT volumes were acquired from the right eyes of 14 normal subjects using two Zeiss-Cirrus SD-OCT scanners. After segmentation of 10 intraretinal layers and rigid registration of layer thickness maps from the repeated OCT scans, the thickness difference of each layer was calculated. The overall mean global and regional thickness differences of 10 intraretinal layers were 0.46 +/- 0.25 μm (1.70 +/- 0.72 %) and 1.16 +/- 0.84 μm (4.03 +/- 2.05 %), respectively. No specific local region showed a consistent thickness difference across the layers.

  12. Use of Mechanical Turk as a MapReduce Framework for Macular OCT Segmentation.

    PubMed

    Lee, Aaron Y; Lee, Cecilia S; Keane, Pearse A; Tufail, Adnan

    2016-01-01

    Purpose. To evaluate the feasibility of using Mechanical Turk as a massively parallel platform to perform manual segmentations of macular spectral domain optical coherence tomography (SD-OCT) images using a MapReduce framework. Methods. A macular SD-OCT volume of 61 slice images was map-distributed to Amazon Mechanical Turk. Each Human Intelligence Task was set to $0.01 and required the user to draw five lines to outline the sublayers of the retinal OCT image after being shown example images. Each image was submitted twice for segmentation, and interrater reliability was calculated. The interface was created using custom HTML5 and JavaScript code, and data analysis was performed using R. An automated pipeline was developed to handle the map and reduce steps of the framework. Results. More than 93,500 data points were collected using this framework for the 61 images submitted. Pearson's correlation of interrater reliability was 0.995 (p < 0.0001) and coefficient of determination was 0.991. The cost of segmenting the macular volume was $1.21. A total of 22 individual Mechanical Turk users provided segmentations, each completing an average of 5.5 HITs. Each HIT was completed in an average of 4.43 minutes. Conclusions. Amazon Mechanical Turk provides a cost-effective, scalable, high-availability infrastructure for manual segmentation of OCT images.

  13. [Age-related Macular Degeneration in the Japanese].

    PubMed

    Yoshimura, Nagahisa

    2016-03-01

    Age-related macular degeneration (AMD) in the Japanese often shows different clinical features from those described in Caucasians. For example, we often observe choroidal neovascularization (CNV) in elderly patients without drusen in the fundus. The high incidence of polypoidal choroidal vasculopathy (PCV) in AMD among Japanese is well-known. The reason why such differences occur in clinical manifestations of AMD has been one of my main interests. In this review article, I will discuss the characteristics of AMD in the Japanese population, as found in our recent study. I. Prevalence and clinical characteristics of AMD in the Japanese population. Cohort studies are important to determine the prevalence and incidence of diseases. In Japan, cohort studies began to be carried out rather late compared with Western countries. Although good cohort studies from Japan are reported in the literature, the size of the cohorts was not sufficiently large to determine the prevalence of AMD. However, a recent meta-analysis of Asian cohorts has shown that the prevalence of late AMD in Asians is not different from that reported in Caucasians. On the other hand, the prevalence of early AMD appears lower in the Japanese than in Caucasians. Recently, we have published the results of the Nagahama Cohort study. In this cohort study, we found a high prevalence of drusen. It seems that the incidence of dry AMD is likely to increase among Japanese. In Japan, most retina specialists classify AMD into three categories : typical AMD, PCV, and retinal angiomatous proliferation (RAP). However, there are no definite diagnostic criteria to distinguish between the three conditions. To compare the clinical features of Japanese and Western cases of AMD, and to determine the incidence of the three types of AMD, we exchanged data about 100 consecutive cases between Kyoto University and Centre d'Ophtalmologie de Paris, France. Interestingly, the diagnoses made by the two institutes were not always in

  14. [Treatment of exudative age-related macular degeneration].

    PubMed

    Yuzawa, M

    2000-12-01

    I PROPHYLACTIC TREATMENT: We followed 75 eyes contralateral to eyes with exudative age-related macular degeneration (AMD), using indocyanine green angiography (IA), for more than one year. Hyperfluorescent areas in the late phase of IA were seen in 19 eyes at the initial examination, and in 25 eyes during follow-up. Exudative AMD developed in 9 of the 25 eyes. Using timetable analysis, we estimated that 11% of these 27 eyes developed AMD within one year and 55% within three years. The hyperfluorescent areas seen on IA appeared to be latent choroidal neovascularization (CNV) under the retinal pigment epithelium. We propose that photocoagulation aimed at hyperfluorescent areas should be considered in such cases. We performed prophylactic laser photocoagulation in 21 eyes, which were then followed up for at least six months. These eyes all had 10 or more serous drusen within 1,500 microns of the fovea and did not show hyperfluorescence, suggesting latent CNV in the late phase of IA. The majority or a small fraction of the serous drusen disappeared in 48% and 18% of the 21 eyes, respectively. CNV appeared adjacent to the laser scar in one eye (5%). Judging from these results, it is important to establish a method of definitively abolishing drusen and preventing the development of CNV. II TREATMENT OF CNV: Of 229 eyes which showed occult CNV in fluorescein angiography (FA), 124 eyes (54%) showed classic CNV outside the fovea on IA. One hundred and two of the 124 eyes (45%) underwent laser photocoagulation. We evaluated indocyanine green guided laser photocoagulation of extrafoveal CNV in 139 eyes. The success rate was 81% at 3 months after laser photocoagulation. This was estimated using timetable analyses to have decreased to 78% at one year and 71% at three years. Eighty percent of successfully treated eyes showed maintained or improved visual acuity. These results did not differ significantly from those obtained with laser photocoagulation based on FA findings. When

  15. [Age-related Macular Degeneration in the Japanese].

    PubMed

    Yoshimura, Nagahisa

    2016-03-01

    Age-related macular degeneration (AMD) in the Japanese often shows different clinical features from those described in Caucasians. For example, we often observe choroidal neovascularization (CNV) in elderly patients without drusen in the fundus. The high incidence of polypoidal choroidal vasculopathy (PCV) in AMD among Japanese is well-known. The reason why such differences occur in clinical manifestations of AMD has been one of my main interests. In this review article, I will discuss the characteristics of AMD in the Japanese population, as found in our recent study. I. Prevalence and clinical characteristics of AMD in the Japanese population. Cohort studies are important to determine the prevalence and incidence of diseases. In Japan, cohort studies began to be carried out rather late compared with Western countries. Although good cohort studies from Japan are reported in the literature, the size of the cohorts was not sufficiently large to determine the prevalence of AMD. However, a recent meta-analysis of Asian cohorts has shown that the prevalence of late AMD in Asians is not different from that reported in Caucasians. On the other hand, the prevalence of early AMD appears lower in the Japanese than in Caucasians. Recently, we have published the results of the Nagahama Cohort study. In this cohort study, we found a high prevalence of drusen. It seems that the incidence of dry AMD is likely to increase among Japanese. In Japan, most retina specialists classify AMD into three categories : typical AMD, PCV, and retinal angiomatous proliferation (RAP). However, there are no definite diagnostic criteria to distinguish between the three conditions. To compare the clinical features of Japanese and Western cases of AMD, and to determine the incidence of the three types of AMD, we exchanged data about 100 consecutive cases between Kyoto University and Centre d'Ophtalmologie de Paris, France. Interestingly, the diagnoses made by the two institutes were not always in

  16. Reduced Fluorescein Angiography and Fundus Photography Use in the Management of Neovascular Macular Degeneration and Macular Edema During the Past Decade

    PubMed Central

    Schneider, Eric W.; Mruthyunjaya, Prithvi; Talwar, Nidhi; Harris Nwanyanwu, Kristen; Nan, Bin; Stein, Joshua D.

    2014-01-01

    Purpose. We assessed recent trends in the use of diagnostic testing for neovascular age-related macular degeneration (NVAMD) and macular edema (ME). Methods. Claims data from a managed-care network were analyzed on patients with NVAMD (n = 22,954) or ME (n = 31,810) to assess the use of fluorescein angiography (FA), fundus photography (FP), and optical coherence tomography (OCT) from 2001 to 2009. Repeated-measures logistic regression was performed to compare patients' odds of undergoing these procedures in 2001, 2005, and 2009. In addition, the proportions of patients with an incident NVAMD or ME diagnosis in 2003 or 2008 who underwent FA, FP, and OCT were compared. Results. From 2001 to 2009, among patients with NVAMD, the odds of undergoing OCT increased 23-fold, whereas the odds of receiving FA and FP decreased by 68% and 79%, respectively. Similar trends were observed for ME. From 2003 to 2008, the proportion of patients undergoing OCT within 1 year of initial diagnosis increased by 315% for NVAMD and by 143% for ME; the proportion undergoing OCT without FA within 1 year increased by 463% for NVAMD and by 216% for ME. Conclusions. Use of OCT increased dramatically during the past decade, whereas use of FA and FP declined considerably, suggesting that OCT may be replacing more traditional diagnostic testing in patients with NVAMD or ME. Future studies should evaluate whether this increased reliance on OCT instead of FA and FP affects patient outcomes. PMID:24346174

  17. Measurement of macular pigment optical density among healthy Chinese people and patients with early-stage age-related macular degeneration

    PubMed Central

    Ren, Xue-Tao; Gu, Hong; Han, Xu; Zhang, Jun-Yan; Li, Xue; Yang, Xiu-Fen; Xu, Jun; Snellingen, Torkel; Liu, Xi-Pu; Wang, Ning-Li; Liu, Ning-Pu

    2015-01-01

    AIM To measure the macular pigment optical density (MPOD) in healthy Chinese people and patients with early age-related macular degeneration (AMD). METHODS Cross-sectional population based study. Demographic and lifestyle characteristics were ascertained by questionnaire. A food frequency questionnaire was completed for all participants. Participants underwent general physical and ophthalmic examinations and MPOD was measured by heterochromatic flicker photometry. Foveal architecture was measured by optical coherence tomography. RESULTS MPOD of 225 participants (122 healthy and 103 early AMD) was 0.48±0.18. Patients with early AMD (0.52±0.19) tended to have higher MPOD levels than healthy people (0.47±0.17), but the difference was not statistically significant (P=0.06). Participants with carrot or corn oil intake every week tended to have higher levels of MPOD (P=0.002 and 0.008 respectively) while those with corn intake had relatively lower level of MPOD (P=0.01). MPOD increased with the center foveal thickness (P=0.01). CONCLUSION Our findings show that there is no statistically significant association between MPOD and early AMD in the studied population. MPOD is related to center foveal thickness and diets would influence MPOD levels. PMID:26682171

  18. Evaluation of the Precision of the Microperimetry Function of the Spectral OCT/SLO

    ClinicalTrials.gov

    2015-10-28

    Age-Related Macular Degeneration,; Geographic Atrophy,; Diabetic Retinopathy,; Macular Edema,; Retinal Vein Occlusion,; Central Serous Retinopathy,; Pattern Dystrophy of Macula; Epiretinal Membrane,; Macular Hole.

  19. Black Holes, Worm Holes, and Future Space Propulsion

    NASA Technical Reports Server (NTRS)

    Barret, Chris

    2000-01-01

    NASA has begun examining the technologies needed for an Interstellar Mission. In 1998, a NASA Interstellar Mission Workshop was held at the California Institute of Technology to examine the technologies required. Since then, a spectrum of research efforts to support such a mission has been underway, including many advanced and futuristic space propulsion concepts which are being explored. The study of black holes and wormholes may provide some of the breakthrough physics needed to travel to the stars. The first black hole, CYGXI, was discovered in 1972 in the constellation Cygnus X-1. In 1993, a black hole was found in the center of our Milky Way Galaxy. In 1994, the black hole GRO J1655-40 was discovered by the NASA Marshall Space Flight center using the Gamma Ray Observatory. Today, we believe we have found evidence to support the existence of 19 black holes, but our universe may contain several thousands. This paper discusses the dead star states - - both stable and unstable, white dwarfs, neutron stars, pulsars, quasars, the basic features and types of black holes: nonspinning, nonspinning with charge, spinning, and Hawking's mini black holes. The search for black holes, gravitational waves, and Laser Interferometer Gravitational Wave Observatory (LIGO) are reviewed. Finally, concepts of black hole powered space vehicles and wormhole concepts for rapid interstellar travel are discussed in relation to the NASA Interstellar Mission.

  20. Macular microvasculature alterations in patients with primary open-angle glaucoma: A cross-sectional study.

    PubMed

    Xu, Huan; Yu, Jian; Kong, Xiangmei; Sun, Xinghuai; Jiang, Chunhui

    2016-08-01

    To evaluate and compare macular microvasculature changes in eyes with primary open-angle glaucoma (POAG) to normal eyes, and to assess associations among the retinal microvasculature, neural structural damage, and visual field loss.Ninety-nine eyes (68 patients with POAG and 31 normal subjects) were enrolled in this study. Thirty-five eyes with early-stage glaucoma (EG), 33 eyes with advanced-stage glaucoma (AG), and 31 normal eyes were included. An optical coherence tomography system with a split-spectrum amplitude-decorrelation angiography algorithm was used to measure the macular capillary vessel area density and retinal thickness. Visual field testing (30-2 and 10-2 programs) was performed using a Humphrey field analyzer. Correlations between the capillary vessel area density, retinal thickness, and visual field parameters were analyzed.Compared to normal eyes, those with EG and AG had a lower macular capillary vessel area density and lesser retinal thickness (P < 0.001, all). Results of multivariate linear regression analyses showed that each standard deviation (SD) decrease in the vessel area density was associated with a 1.5% and 4.2% thinning of the full retinal thickness and inner retinal layer thickness, respectively. Each SD decrease in the vessel area density was also associated with a 12.9% decrease in the mean sensitivity and a 33.6% increase in the pattern standard deviation (P < 0.001, both). The Pearson partial regression analysis model showed that the vessel area density was most strongly associated with the inner retinal layer thickness and inferior hemimacular thickness. Furthermore, a lower vessel area density was strongly associated with a more severe hemimacular visual field defect and the corresponding hemimacular retinal thickness.The macular capillary vessel area density and retinal thickness were significantly lower in eyes with POAG than in normal eyes. A diminished macular microvasculature network is closely associated with

  1. Macular spectral domain optical coherence tomography findings in Tanzanian endemic optic neuropathy.

    PubMed

    Kisimbi, John; Shalchi, Zaid; Mahroo, Omar A; Mhina, Celina; Sanyiwa, Anna J; Mabey, Denise; Mohamed, Moin; Plant, Gordon T

    2013-11-01

    Bilateral optic neuropathy in Dar es Salaam is now considered endemic and is estimated to affect 0.3-2.4% of young adults. The condition is characterized by a subacute bilateral loss of central vision of unknown aetiology. Findings of spectral domain optical coherence tomography have not previously been reported for these patients. All patients diagnosed with endemic optic neuropathy over a 2-year period at the Muhimbili National Hospital underwent spectral domain optical coherence tomography macular imaging. Scans were graded qualitatively for severity of retinal nerve fibre layer loss as well as the presence of microcystic macular changes, which have not previously been described in this condition. Of the 128 patients included (54.7% male; median age 20 years), severe retinal nerve fibre layer loss was found in 185 eyes (74.0%). There was full concordance in retinal nerve fibre layer thickness between the two eyes in 113 (91.1%) patients. Microcystic macular spaces were found in 16 (12.5%) patients and were bilateral in nine (7.0%) individuals. These changes were typically more prominent in the nasal than the temporal macula, predominantly involving the inner nuclear layer, and often occurred in an annular configuration that was evident on en face infra-red imaging, though not discernible on colour fundus photography or clinically. All patients with microcystic macular changes had severe thinning of the retinal nerve fibre layer (P = 0.02). Four patients in whom cystic spaces were demonstrated had sequential scans, and there was no detectable alteration in the configuration of these changes over a period of up to 16 months. This is the first study to document optical coherence tomography findings in endemic optic neuropathy. We have observed symmetrical severe loss of the caeco-central projection (papillomacular bundle) with otherwise well-preserved macular architecture. Also, we have observed microcystic retinal changes in a significant proportion of patients

  2. The First Black Holes

    NASA Astrophysics Data System (ADS)

    Abel, T.

    star. Within this wide range of possible initial masses the death of these star will lead very different remnants (Heger and Woosley 2001). In the case of stars with masses larger than 260 solar mass no metals may be released in black holes are the natural outcome. This may be an interesting possibility to form intermediate mass black holes which are attractive seeds to be nurtured to the super-massive black holes observed in the centers of nearby galaxies. However, no metals would be released and it would prove difficult to understand the transition to the formation of low mass metal enriched population II stars. Stars with masses below 140 solar masses would enrich the intergalactic medium as well as form massive black holes. The coincidence of the Kelvin Helmholtz time with our computed accretion times at about 120 solar masses may argue in favor of such smaller masses. These first black holes may well leave the halos in which they formed for even rather modest kick velocities >~ 10 km/s. Nevertheless, up to about one hundred thousand of these first black holes may remain in the Milky Way. The realization that structure formation began within one hundred million years after big bang makes it difficult to study observationally these first crucial steps. Future observatories have hence to focus on larger collecting areas and wavelengths for which the universe is transparent up to redshifts of 30. XEUS offers the chance to open a new window to these so far dark ages. The limiting masses quoted here rely on stellar models of primordial stars that do not include rotation, magnetic fields or mass loss and hence are somewhat uncertain.

  3. Bore hole navigator

    SciTech Connect

    Hoffman, G.J.

    1987-09-29

    A bore hole navigator is described comprising a two axis platform for lowering down a bore hole on a cable with its longitudinal axis parallel to the local bore hole direction. The two axis platform has an outer gimbal, bearing supported on the outer gimbal axis for rotation about the longitudinal axis of the platform, and an inner gimbal axis orthogonal the the outer gimbal axis. The inner gimbal axis has multiple axis segments spaced along the longitudinal axis of the platform and each bearing supported on the outer gimbal. The inner gimbal axis segment has a two axis gyro mounted thereon with its spin axis orthogonal to the respective inner gimbal axis segment, a first gyro sensitive axis parallel to the respective inner gimbal axis segment and a second gyro sensitive axis orthogonal to the spin axis. The second inner gimbal axis segment has a pitch torquer thereon operative to provide a controllable torque about the respective inner gimbal axis segment. The third inner gimbal axis segment has a pitch resolver thereon operative to measure rotation of the respective inner gimbal axis segment with respect to the outer gimbal. The first, second and third inner gimbal axis segments are coupled to rotate together. The outer gimbal has a yaw torquer thereon to provide a controllable torque about the outer gimbal axis, and a yaw resolver thereon to measure rotation of the outer gimbal about the outer gimbal axis. The outer gimbal also has a single axis accelerometer therein having its sensitive axis orthogonal to the outer gimbal axis and the inner gimbal axis segments.

  4. Deep Hole in 'Clovis'

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site] Figure 1

    At a rock called 'Clovis,' the rock abrasion tool on NASA's Mars Exploration Rover Spirit cut a 9-millimeter (0.35-inch) hole during the rover's 216th martian day, or sol (Aug. 11, 2004). The hole is the deepest drilled in a rock on Mars so far. This approximately true-color view was made from images taken by Spirit's panoramic camera on sol 226 (Aug. 21, 2004) at around 12:50 p.m. local true solar time -- early afternoon in Gusev Crater on Mars. To the right is a 'brush flower' of circles produced by scrubbing the surface of the rock with the abrasion tool's wire brush. Scientists used rover's Moessbauer spectrometer and alpha particle X-ray spectrometer to look for iron-bearing minerals and determine the elemental chemical composition of the rock. This composite combines images taken with the camera's 750-, 530-, and 430-nanometer filters. The grayish-blue hue in this image suggests that the interior of the rock contains iron minerals that are less oxidized than minerals on the surface. The diameter of the hole cut into the rock is 4.5 centimeters (1.8 inches).

    Data on the graph (Figure 1) from the alpha particle X-ray spectrometer instrument on the robotic arm of NASA's Mars Exploration Rover Spirit reveal the elemental chemistry of two rocks, 'Ebenezer' and 'Clovis,' (see PIA06914) in the 'Columbia Hills.' Scientists found, through comparison of the rocks' chemistry, that Ebenezer and Clovis have very different compositions from the rocks on the Gusev plains.

  5. Ultrarelativistic black hole formation.

    PubMed

    East, William E; Pretorius, Frans

    2013-03-01

    We study the head-on collision of fluid particles well within the kinetic energy dominated regime (γ = 8 to 12) by numerically solving the Einstein-hydrodynamic equations. We find that the threshold for black hole formation is lower (by a factor of a few) than simple hoop conjecture estimates, and, moreover, near this threshold two distinct apparent horizons first form postcollision and then merge. We argue that this can be understood in terms of a gravitational focusing effect. The gravitational radiation reaches luminosities of 0.014 c(5)/G, carrying 16 ± 2% of the total energy.

  6. Surfing a Black Hole

    NASA Astrophysics Data System (ADS)

    2002-10-01

    Star Orbiting Massive Milky Way Centre Approaches to within 17 Light-Hours [1] Summary An international team of astronomers [2], lead by researchers at the Max-Planck Institute for Extraterrestrial Physics (MPE) , has directly observed an otherwise normal star orbiting the supermassive black hole at the center of the Milky Way Galaxy. Ten years of painstaking measurements have been crowned by a series of unique images obtained by the Adaptive Optics (AO) NAOS-CONICA (NACO) instrument [3] on the 8.2-m VLT YEPUN telescope at the ESO Paranal Observatory. It turns out that earlier this year the star approached the central Black Hole to within 17 light-hours - only three times the distance between the Sun and planet Pluto - while travelling at no less than 5000 km/sec . Previous measurements of the velocities of stars near the center of the Milky Way and variable X-ray emission from this area have provided the strongest evidence so far of the existence of a central Black Hole in our home galaxy and, implicitly, that the dark mass concentrations seen in many nuclei of other galaxies probably are also supermassive black holes. However, it has not yet been possible to exclude several alternative configurations. In a break-through paper appearing in the research journal Nature on October 17th, 2002, the present team reports their exciting results, including high-resolution images that allow tracing two-thirds of the orbit of a star designated "S2" . It is currently the closest observable star to the compact radio source and massive black hole candidate "SgrA*" ("Sagittarius A") at the very center of the Milky Way. The orbital period is just over 15 years. The new measurements exclude with high confidence that the central dark mass consists of a cluster of unusual stars or elementary particles, and leave little doubt of the presence of a supermassive black hole at the centre of the galaxy in which we live . PR Photo 23a/02 : NACO image of the central region of the Milky Way

  7. Acceleration of black hole universe

    NASA Astrophysics Data System (ADS)

    Zhang, T. X.; Frederick, C.

    2014-01-01

    Recently, Zhang slightly modified the standard big bang theory and developed a new cosmological model called black hole universe, which is consistent with Mach's principle, governed by Einstein's general theory of relativity, and able to explain all observations of the universe. Previous studies accounted for the origin, structure, evolution, expansion, and cosmic microwave background radiation of the black hole universe, which grew from a star-like black hole with several solar masses through a supermassive black hole with billions of solar masses to the present state with hundred billion-trillions of solar masses by accreting ambient matter and merging with other black holes. This paper investigates acceleration of the black hole universe and provides an alternative explanation for the redshift and luminosity distance measurements of type Ia supernovae. The results indicate that the black hole universe accelerates its expansion when it accretes the ambient matter in an increasing rate. In other words, i.e., when the second-order derivative of the mass of the black hole universe with respect to the time is positive . For a constant deceleration parameter , we can perfectly explain the type Ia supernova measurements with the reduced chi-square to be very close to unity, χ red˜1.0012. The expansion and acceleration of black hole universe are driven by external energy.

  8. Black holes as antimatter factories

    NASA Astrophysics Data System (ADS)

    Bambi, Cosimo; Dolgov, Alexander D.; Petrov, Alexey A.

    2009-09-01

    We consider accretion of matter onto a low mass black hole surrounded by ionized medium. We show that, because of the higher mobility of protons than electrons, the black hole would acquire positive electric charge. If the black hole's mass is about or below 1020 g, the electric field at the horizon can reach the critical value which leads to vacuum instability and electron-positron pair production by the Schwinger mechanism. Since the positrons are ejected by the emergent electric field, while electrons are back-captured, the black hole operates as an antimatter factory which effectively converts protons into positrons.

  9. Black holes and the multiverse

    NASA Astrophysics Data System (ADS)

    Garriga, Jaume; Vilenkin, Alexander; Zhang, Jun

    2016-02-01

    Vacuum bubbles may nucleate and expand during the inflationary epoch in the early universe. After inflation ends, the bubbles quickly dissipate their kinetic energy; they come to rest with respect to the Hubble flow and eventually form black holes. The fate of the bubble itself depends on the resulting black hole mass. If the mass is smaller than a certain critical value, the bubble collapses to a singularity. Otherwise, the bubble interior inflates, forming a baby universe, which is connected to the exterior FRW region by a wormhole. A similar black hole formation mechanism operates for spherical domain walls nucleating during inflation. As an illustrative example, we studied the black hole mass spectrum in the domain wall scenario, assuming that domain walls interact with matter only gravitationally. Our results indicate that, depending on the model parameters, black holes produced in this scenario can have significant astrophysical effects and can even serve as dark matter or as seeds for supermassive black holes. The mechanism of black hole formation described in this paper is very generic and has important implications for the global structure of the universe. Baby universes inside super-critical black holes inflate eternally and nucleate bubbles of all vacua allowed by the underlying particle physics. The resulting multiverse has a very non-trivial spacetime structure, with a multitude of eternally inflating regions connected by wormholes. If a black hole population with the predicted mass spectrum is discovered, it could be regarded as evidence for inflation and for the existence of a multiverse.

  10. How black holes saved relativity

    NASA Astrophysics Data System (ADS)

    Prescod-Weinstein, Chanda

    2016-02-01

    While there have been many popular-science books on the historical and scientific legacy of Albert Einstein's general theory of relativity, a gap exists in the literature for a definitive, accessible history of the theory's most famous offshoot: black holes. In Black Hole, the science writer Marcia Bartusiak aims for a discursive middle ground, writing solely about black holes at a level suitable for both high-school students and more mature readers while also giving some broader scientific context for black-hole research.

  11. String duality and black holes

    NASA Astrophysics Data System (ADS)

    Kalara, S.; Nanopoulos, D. V.

    1991-09-01

    In the context of (semi) classical general relativity, the physics of black holes poses many unanswered and unsettling questions. Notable among them are the loss of quantum coherence, which casts doubts on the basic foundations of quantum mechanics, and the understanding of the enormous entropy carried by black holes which is at odds with strong ``no hair'' theorems. We point out that in string theory, black-hole type solutions (S-black holes) carry local discrete charges inherited from the duality symmetries of the string, which allow S-black holes to carry ``quantum hair''. It is further noted that the conservation of the discrete charges and the presence of quantum hair precludes the information about a quantum state from being completely lost in the black hole thus rescuing quantum coherence. We also note that a large number of quantum hair carried by S-black holes may explain their enormous entropy, i.e. it is the duality symmetry of the string theory which redeems outstanding problems of black-hole dynamics. We also discuss a possible description of black holes as solitons of string theory. Supported in part by DOE Grant DE-AS05-81 ER40039.

  12. Can Black Hole Relax Unitarily?

    NASA Astrophysics Data System (ADS)

    Solodukhin, S. N.

    2005-03-01

    We review the way the BTZ black hole relaxes back to thermal equilibrium after a small perturbation and how it is seen in the boundary (finite volume) CFT. The unitarity requires the relaxation to be quasi-periodic. It is preserved in the CFT but is not obvious in the case of the semiclassical black hole the relaxation of which is driven by complex quasi-normal modes. We discuss two ways of modifying the semiclassical black hole geometry to maintain unitarity: the (fractal) brick wall and the worm-hole modification. In the latter case the entropy comes out correctly as well.

  13. Thermodynamics of Accelerating Black Holes

    NASA Astrophysics Data System (ADS)

    Appels, Michael; Gregory, Ruth; KubizÅák, David

    2016-09-01

    We address a long-standing problem of describing the thermodynamics of an accelerating black hole. We derive a standard first law of black hole thermodynamics, with the usual identification of entropy proportional to the area of the event horizon—even though the event horizon contains a conical singularity. This result not only extends the applicability of black hole thermodynamics to realms previously not anticipated, it also opens a possibility for studying novel properties of an important class of exact radiative solutions of Einstein equations describing accelerated objects. We discuss the thermodynamic volume, stability, and phase structure of these black holes.

  14. Age Related Macular Degeneration and Total Hip Replacement Due to Osteoarthritis or Fracture: Melbourne Collaborative Cohort Study.

    PubMed

    Chong, Elaine W; Wang, Yuanyuan; Robman, Liubov D; Aung, Khin Zaw; Makeyeva, Galina A; Giles, Graham G; Graves, Stephen; Cicuttini, Flavia M; Guymer, Robyn H

    2015-01-01

    Osteoarthritis is the leading cause of total hip replacement, accounting for more than 80% of all total hip replacements. Emerging evidence suggests that osteoarthritis has a chronic inflammatory component to its pathogenesis similar to age-related macular degeneration. We evaluated the association between age-related macular degeneration and total hip replacement as proxy for severe osteoarthritis or fractured neck of femur in the Melbourne Collaborative Cohort Study. 20,744 participants had complete data on both age-related macular degeneration assessed from colour fundus photographs taken during 2003-2007 and total hip replacement. Total hip replacements due to hip osteoarthritis and fractured neck of femur during 2001-2011 were identified by linking the cohort records to the Australian Orthopedic Association National Joint Replacement Registry. Logistic regression was used to examine the association between age-related macular degeneration and risk of total hip replacement due to osteoarthritis and fracture separately, adjusted for confounders. There were 791 cases of total hip replacement for osteoarthritis and 102 cases of total hip replacement due to fractured neck of femur. After adjustment for age, sex, body mass index, smoking, and grouped country of birth, intermediate age-related macular degeneration was directly associated with total hip replacement for osteoarthritis (odds ratio 1.22, 95% CI 1.00-1.49). Late age-related macular degeneration was directly associated with total hip replacement due to fractured neck of femur (odds ratio 5.21, 95% CI2.25-12.02). The association between intermediate age-related macular degeneration and an increased 10-year incidence of total hip replacement due to osteoarthritis suggests the possibility of similar inflammatory processes underlying both chronic diseases. The association of late age-related macular degeneration with an increased 10-year incidence of total hip replacement due to fractured neck of femur may be

  15. Age Related Macular Degeneration and Total Hip Replacement Due to Osteoarthritis or Fracture: Melbourne Collaborative Cohort Study.

    PubMed

    Chong, Elaine W; Wang, Yuanyuan; Robman, Liubov D; Aung, Khin Zaw; Makeyeva, Galina A; Giles, Graham G; Graves, Stephen; Cicuttini, Flavia M; Guymer, Robyn H

    2015-01-01

    Osteoarthritis is the leading cause of total hip replacement, accounting for more than 80% of all total hip replacements. Emerging evidence suggests that osteoarthritis has a chronic inflammatory component to its pathogenesis similar to age-related macular degeneration. We evaluated the association between age-related macular degeneration and total hip replacement as proxy for severe osteoarthritis or fractured neck of femur in the Melbourne Collaborative Cohort Study. 20,744 participants had complete data on both age-related macular degeneration assessed from colour fundus photographs taken during 2003-2007 and total hip replacement. Total hip replacements due to hip osteoarthritis and fractured neck of femur during 2001-2011 were identified by linking the cohort records to the Australian Orthopedic Association National Joint Replacement Registry. Logistic regression was used to examine the association between age-related macular degeneration and risk of total hip replacement due to osteoarthritis and fracture separately, adjusted for confounders. There were 791 cases of total hip replacement for osteoarthritis and 102 cases of total hip replacement due to fractured neck of femur. After adjustment for age, sex, body mass index, smoking, and grouped country of birth, intermediate age-related macular degeneration was directly associated with total hip replacement for osteoarthritis (odds ratio 1.22, 95% CI 1.00-1.49). Late age-related macular degeneration was directly associated with total hip replacement due to fractured neck of femur (odds ratio 5.21, 95% CI2.25-12.02). The association between intermediate age-related macular degeneration and an increased 10-year incidence of total hip replacement due to osteoarthritis suggests the possibility of similar inflammatory processes underlying both chronic diseases. The association of late age-related macular degeneration with an increased 10-year incidence of total hip replacement due to fractured neck of femur may be

  16. Age Related Macular Degeneration and Total Hip Replacement Due to Osteoarthritis or Fracture: Melbourne Collaborative Cohort Study

    PubMed Central

    Chong, Elaine W.; Wang, Yuanyuan; Robman, Liubov D.; Aung, Khin Zaw; Makeyeva, Galina A.; Giles, Graham G.; Graves, Stephen; Cicuttini, Flavia M.; Guymer, Robyn H.

    2015-01-01

    Osteoarthritis is the leading cause of total hip replacement, accounting for more than 80% of all total hip replacements. Emerging evidence suggests that osteoarthritis has a chronic inflammatory component to its pathogenesis similar to age-related macular degeneration. We evaluated the association between age-related macular degeneration and total hip replacement as proxy for severe osteoarthritis or fractured neck of femur in the Melbourne Collaborative Cohort Study. 20,744 participants had complete data on both age-related macular degeneration assessed from colour fundus photographs taken during 2003–2007 and total hip replacement. Total hip replacements due to hip osteoarthritis and fractured neck of femur during 2001–2011 were identified by linking the cohort records to the Australian Orthopedic Association National Joint Replacement Registry. Logistic regression was used to examine the association between age-related macular degeneration and risk of total hip replacement due to osteoarthritis and fracture separately, adjusted for confounders. There were 791 cases of total hip replacement for osteoarthritis and 102 cases of total hip replacement due to fractured neck of femur. After adjustment for age, sex, body mass index, smoking, and grouped country of birth, intermediate age-related macular degeneration was directly associated with total hip replacement for osteoarthritis (odds ratio 1.22, 95% CI 1.00–1.49). Late age-related macular degeneration was directly associated with total hip replacement due to fractured neck of femur (odds ratio 5.21, 95% CI2.25–12.02). The association between intermediate age-related macular degeneration and an increased 10-year incidence of total hip replacement due to osteoarthritis suggests the possibility of similar inflammatory processes underlying both chronic diseases. The association of late age-related macular degeneration with an increased 10-year incidence of total hip replacement due to fractured neck of femur

  17. A Review of Randomized Trials of Approved Pharmaceutical Agents for Macular Edema Secondary to Retinal Vein Occlusion.

    PubMed

    Wang, Jia-Kang

    2016-01-01

    There are 3 approved pharmaceutical agents for treating macular edema secondary to retinal vein occlusion (RVO): dexamethasone (a corticosteroid) implant and ranibizumab and aflibercept (both antivascular endothelial growth factor agents). All show a superior ability to improve vision and reduce macular thickness in comparison with sham injections or macular grid laser treatment. Prompt treatment with these agents may lead to a better outcome. A review of randomized trials of injected aflibercept or ranibizumab reveals protocol variations. They include "as needed" injections until functional and anatomical changes are achieved, preceded by either 1 injection or 3 to 6 monthly injections as loading doses. Ocular and systemic adverse effects of vascular endothelial growth factor antagonists for macular edema secondary to RVO are rarely severe. The antiedematous response to a single intravitreal dexamethasone implant is maximal 1 to 3 months after the injection. Intraocular pressure elevation and cataract aggravation should be monitored after the use of intravitreal dexamethasone implants. Intravitreal dexamethasone implants and ranibizumab injections reduce not only macular edema, but also the risk of retinal ischemia and neovascularization in patients with RVO. PMID:26692257

  18. Association between retinal hemorrhagic pattern and macular perfusion status in eyes with acute branch retinal vein occlusion

    PubMed Central

    Muraoka, Yuki; Uji, Akihito; Tsujikawa, Akitaka; Murakami, Tomoaki; Ooto, Sotaro; Suzuma, Kiyoshi; Takahashi, Ayako; Iida, Yuto; Miwa, Yuko; Hata, Masayuki; Yoshimura, Nagahisa

    2016-01-01

    This prospective study included 63 eyes with acute branch retinal vein occlusion (BRVO) to evaluate the retinal hemorrhagic patterns at the posterior poles and explore their clinical relevance in macular perfusion differentiation. Retinal hemorrhagic patterns and macular perfusion status were evaluated via fundus photography and fluorescein angiography, respectively. Macular perfusion was judged as nonischemic in 30, ischemic in 28, and undeterminable in 5 among the 63 eyes. Predominant hemorrhagic patterns were flame-shaped in 39 (67.2%) and non-flame-shaped in 19 (32.8%) eyes. All 39 eyes with a flame-shaped hemorrhage showed a nonischemic macula. Of the 19 eyes classified as having a non-flame-shaped hemorrhage, 13 (68.4%) had an ischemic macula and 6 (31.6%) had a nonischemic macula (P < 0.001). Parallelism in eyes with a flame-shaped hemorrhage was higher than in those with a non-flame-shaped hemorrhage (P < 0.001), and in those with a nonischemic macula versus those with an ischemic macula (P < 0.001). The area under the curve for parallelism was 0.975 (P < 0.001), suggesting an accurate diagnostic parameter for macular perfusion differentiation. In conclusion, we objectively evaluated retinal hemorrhagic patterns at the posterior pole in BRVO using the parallelism method, which was useful in differentiating macular perfusion status. PMID:27334338

  19. Circulating Autoantibodies in Age-Related Macular Degeneration Recognize Human Macular Tissue Antigens Implicated in Autophagy, Immunomodulation, and Protection from Oxidative Stress and Apoptosis

    PubMed Central

    Iannaccone, Alessandro; Giorgianni, Francesco; New, David D.; Hollingsworth, T. J.; Umfress, Allison; Alhatem, Albert H.; Neeli, Indira; Lenchik, Nataliya I.; Jennings, Barbara J.; Calzada, Jorge I.; Satterfield, Suzanne; Mathews, Dennis; Diaz, Rocio I.; Harris, Tamara; Johnson, Karen C.; Charles, Steve; Kritchevsky, Stephen B.; Gerling, Ivan C.; Beranova-Giorgianni, Sarka; Radic, Marko Z.

    2015-01-01

    Background We investigated sera from elderly subjects with and without age-related macular degeneration (AMD) for presence of autoantibodies (AAbs) against human macular antigens and characterized their identity. Methods Sera were collected from participants in the Age-Related Maculopathy Ancillary (ARMA) Study, a cross-sectional investigation ancillary to the Health ABC Study, enriched with participants from the general population. The resulting sample (mean age: 79.2±3.9 years old) included subjects with early to advanced AMD (n = 131) and controls (n = 231). Sera were tested by Western blots for immunoreactive bands against human donor macular tissue homogenates. Immunoreactive bands were identified and graded, and odds ratios (OR) calculated. Based on these findings, sera were immunoprecipitated, and subjected to 2D gel electrophoresis (GE). Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to identify the targets recognized by circulating AAbs seen on 2D-GE, followed by ELISAs with recombinant proteins to confirm LC-MS/MS results, and quantify autoreactivities. Results In AMD, 11 immunoreactive bands were significantly more frequent and 13 were significantly stronger than in controls. Nine of the more frequent bands also showed stronger reactivity. OR estimates ranged between 4.06 and 1.93, and all clearly excluded the null value. Following immunoprecipitation, 2D-GE and LC-MS/MS, five of the possible autoreactivity targets were conclusively identified: two members of the heat shock protein 70 (HSP70) family, HSPA8 and HSPA9; another member of the HSP family, HSPB4, also known as alpha-crystallin A chain (CRYAA); Annexin A5 (ANXA5); and Protein S100-A9, also known as calgranulin B that, when complexed with S100A8, forms calprotectin. ELISA testing with recombinant proteins confirmed, on average, significantly higher reactivities against all targets in AMD samples compared to controls. Conclusions Consistent with other evidence supporting the

  20. Tool For Making Curved Holes

    NASA Technical Reports Server (NTRS)

    Allard, Robert; Calve, Andrew; Pastreck, Edwin; Padden, Edward

    1992-01-01

    Tool for use in electrical-discharge machining (EDM) guides EDM electrode in making curved holes. Guide rod fits in slot in arm, which moves through arc. Motion drives electrode into workpiece along desired curved path. Electrode burns into workpiece while arm rotates on spindle. Discharge cuts hole of same radius of curvature.

  1. Distorted stationary rotating black holes

    NASA Astrophysics Data System (ADS)

    Shoom, Andrey A.

    2015-03-01

    We study the interior of distorted stationary rotating black holes on the example of a Kerr black hole distorted by external static and axisymmetric mass distribution. We show that there is a duality transformation between the outer and inner horizons of the black hole, which is different from that of an electrically charged static distorted black hole. The duality transformation is directly related to the discrete symmetry of the space-time. The black hole horizon areas, surface gravity, and angular momentum satisfy the Smarr formula constructed for both the horizons. We formulate the zeroth, the first, and the second laws of black hole thermodynamics for both the horizons of the black hole and show the correspondence between the local and the global forms of the first law. The Smarr formula and the laws of thermodynamics formulated for both the horizons are related by the duality transformation. The distortion is illustrated on the example of a quadrupole and octupole fields. The distortion fields noticeably affect the proper time of a free fall from the outer to the inner horizon of the black hole along the symmetry semiaxes. There is some minimal nonzero value of the quadrupole and octupole moments when the time becomes minimal. The minimal proper time indicates the closest approach of the horizons due to the distortion.

  2. Thermodynamic Curvature and Black Holes

    NASA Astrophysics Data System (ADS)

    Ruppeiner, George

    In my talk, I will discuss black hole thermodynamics, particularly what happens when you add thermodynamic curvature to the mix. Although black hole thermodynamics is a little off the main theme of this workshop, I hope nevertheless that my message will be of some interest to researchers in supersymmetry and supergravity.

  3. String-Corrected Black Holes

    SciTech Connect

    Hubeny, Veronika; Maloney, Alexander; Rangamani, Mukund

    2005-02-07

    We investigate the geometry of four dimensional black hole solutions in the presence of stringy higher curvature corrections to the low energy effective action. For certain supersymmetric two charge black holes these corrections drastically alter the causal structure of the solution, converting seemingly pathological null singularities into timelike singularities hidden behind a finite area horizon. We establish, analytically and numerically, that the string-corrected two-charge black hole metric has the same Penrose diagram as the extremal four-charge black hole. The higher derivative terms lead to another dramatic effect -- the gravitational force exerted by a black hole on an inertial observer is no longer purely attractive! The magnitude of this effect is related to the size of the compactification manifold.

  4. When Charged Black Holes Merge

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-08-01

    Most theoretical models assume that black holes arent charged. But a new study shows that mergers of charged black holes could explain a variety of astrophysical phenomena, from fast radio bursts to gamma-ray bursts.No HairThe black hole no hair theorem states that all black holes can be described by just three things: their mass, their spin, and their charge. Masses and spins have been observed and measured, but weve never measured the charge of a black hole and its widely believed that real black holes dont actually have any charge.That said, weve also never shown that black holes dont have charge, or set any upper limits on the charge that they might have. So lets suppose, for a moment, that its possible for a black hole to be charged. How might that affect what we know about the merger of two black holes? A recent theoretical study by Bing Zhang (University of Nevada, Las Vegas) examines this question.Intensity profile of a fast radio burst, a sudden burst of radio emission that lasts only a few milliseconds. [Swinburne Astronomy Productions]Driving TransientsZhangs work envisions a pair of black holes in a binary system. He argues that if just one of the black holes carries charge possibly retained by a rotating magnetosphere then it may be possible for the system to produce an electromagnetic signal that could accompany gravitational waves, such as a fast radio burst or a gamma-ray burst!In Zhangs model, the inspiral of the two black holes generates a global magnetic dipole thats perpendicular to the plane of the binarys orbit. The magnetic flux increases rapidly as the separation between the black holes decreases, generating an increasingly powerful magnetic wind. This wind, in turn, can give rise to a fast radio burst or a gamma-ray burst, depending on the value of the black holes charge.Artists illustration of a short gamma-ray burst, thought to be caused by the merger of two compact objects. [ESO/A. Roquette]Zhang calculates lower limits on the charge

  5. Black-Hole Feedback in Quasars

    NASA Video Gallery

    This animation illustrates how black-hole feedback works in quasars. Dense gas and dust in the center simultaneously fuels the black hole and shrouds it from view. The black-hole wind propels large...

  6. Fear of holes.

    PubMed

    Cole, Geoff G; Wilkins, Arnold J

    2013-10-01

    Phobias are usually described as irrational and persistent fears of certain objects or situations, and causes of such fears are difficult to identify. We describe an unusual but common phobia (trypophobia), hitherto unreported in the scientific literature, in which sufferers are averse to images of holes. We performed a spectral analysis on a variety of images that induce trypophobia and found that the stimuli had a spectral composition typically associated with uncomfortable visual images, namely, high-contrast energy at midrange spatial frequencies. Critically, we found that a range of potentially dangerous animals also possess this spectral characteristic. We argue that although sufferers are not conscious of the association, the phobia arises in part because the inducing stimuli share basic visual characteristics with dangerous organisms, characteristics that are low level and easily computed, and therefore facilitate a rapid nonconscious response.

  7. Regular phantom black holes.

    PubMed

    Bronnikov, K A; Fabris, J C

    2006-06-30

    We study self-gravitating, static, spherically symmetric phantom scalar fields with arbitrary potentials (favored by cosmological observations) and single out 16 classes of possible regular configurations with flat, de Sitter, and anti-de Sitter asymptotics. Among them are traversable wormholes, bouncing Kantowski-Sachs (KS) cosmologies, and asymptotically flat black holes (BHs). A regular BH has a Schwarzschild-like causal structure, but the singularity is replaced by a de Sitter infinity, giving a hypothetic BH explorer a chance to survive. It also looks possible that our Universe has originated in a phantom-dominated collapse in another universe, with KS expansion and isotropization after crossing the horizon. Explicit examples of regular solutions are built and discussed. Possible generalizations include k-essence type scalar fields (with a potential) and scalar-tensor gravity.

  8. Digesting the doughnut hole.

    PubMed

    Joyce, Geoffrey F; Zissimopoulos, Julie; Goldman, Dana P

    2013-12-01

    Despite its success, Medicare Part D has been widely criticized for the gap in coverage, the so-called "doughnut hole". We compare the use of prescription drugs among beneficiaries subject to the coverage gap with usage among beneficiaries who are not exposed to it. We find that the coverage gap does, indeed, disrupt the use of prescription drugs among seniors with diabetes. But the declines in usage are modest and concentrated among higher cost, brand-name medications. Demand for high cost medications such as antipsychotics, antiasthmatics, and drugs of the central nervous system decline by 8-18% in the coverage gap, while use of lower cost medications with high generic penetration such as beta blockers, ACE inhibitors and antidepressants decline by 3-5% after reaching the gap. More importantly, lower adherence to medications is not associated with increases in medical service use. PMID:24308883

  9. Foveal and Macular Thickness Evaluation by Spectral OCT SLO and Its Relation with Axial Length in Various Degree of Myopia

    PubMed Central

    Samuel, Nancy Elizabeth

    2015-01-01

    Purpose: To evaluate the foveal and macular thickness in various degrees of myopia and its association with axial length in low, moderate and high degrees of myopia. Design: A cross-sectional study was done in the Department of Ophthalmology, MGMCRI, Pondicherry, India. Materials and Methods: One hundred and twenty five eyes eyes of 64 myopic subjects between the age group of 20-40 who fulfilled the inclusion criteria were selected and complete ophthalmic examination was done. Cycloplegic refraction was done and the subjects were categorized into low (n=43 eyes), moderate (n=43 eyes) and high (n=36) degrees of myopia. The foveal and macular thickness was assessed using spectral OCT- SLO and axial length was measured by A-scan biometry. Results: The foveae minimum of high myopia (178 ± 26.4 microns) was significantly thicker compared to moderate myopia (p= 0.028). There was no significant intergroup difference in the thickness significance of the outer and inner macular between mild, moderate and high degree of myopia. The mean axial length of high myopia (26.7±0.97mm) was significantly higher compared to moderate (24.6±0.81mm) and low myopia (23.5±0.81mm) with a p-value of p = 0.001. There was a positive correlation of axial length with foveae minimum, fovea and superior inner macula in respect to myopia (p<0.05). Conclusion: The foveal and macular thickness in myopia is influenced by the axial length. Early detection of such changes in macular thickness by using OCT is helpful in understanding the mechanism and factors affecting the structural changes of myopic eyes. Also it implicates the importance of refractive error induced retinal macular changes while interpreting OCT. PMID:25954643

  10. [Non-pharmacologic therapy of age-related macular degeneration, based on the etiopathogenesis of the disease].

    PubMed

    Fischer, Tamás

    2015-07-12

    It has a great therapeutic significance that the disorder of the vascular endothelium, which supplies the affected ocular structures, plays a major role in the development of age-related macular degeneration. Chronic inflammation is closely linked to diseases associated with endothelial dysfuncition and age-related macular degeneration is accompanied by a general inflammatory response. The vascular wall including those in chorioids may be activated by several repeated and/or prolonged mechanical, physical, chemical, microbiological, immunologic and genetic factors causing a protracted host defence response with a consequent vascular damage, which leads to age-related macular degeneration. Based on this concept, age-related macular degeneration is a local manifestation of the systemic vascular disease. This recognition should have therapeutic implications because restoration of endothelial dysfunction can stabilize the condition of chronic vascular disease including age-related macular degeneration, as well. Restoration of endothelial dysfunction by non-pharmacological or pharmacological interventions may prevent the development or improve endothelial dysfunction resulting in prevention or improvement of age-related macular degeneration. Non-pharmacological interventions which may have beneficial effect in endothelial dysfunction include (1) smoking cessation; (2) reduction of increased body weight; (3) adequate physical activity; (4) appropriate diet (a) proper dose of flavonoids, polyphenols and kurcumin; (b) omega-3 long-chain polyunsaturated fatty acids: docosahexaenoic acid and eicosapentaenoic acid; (c) carotenoids, lutein and zeaxanthins), (d) management of dietary glycemic index, (e) caloric restriction, and (5) elimination of stressful lifestyle. Non-pharmacological interventions should be preferable even if medicaments are also used for the treatment of endothelial dysfunction.

  11. Macular circulation in patients with diabetes mellitus with and without arterial hypertension

    PubMed Central

    Arend, O; Ruffer, M; Remky, A

    2000-01-01

    BACKGROUND—Previous fluorescein angiographic studies have shown alterations in the macular microcirculation in patients with diabetes mellitus and arterial hypertension. In both diseases capillary blood velocity was reduced and capillary density decreased. These changes were more pronounced in diabetic patients. We have examined the influence of arterial hypertension in combination with diabetes mellitus.
METHODS—62 patients with diabetes mellitus and arterial hypertension (group 1) were matched with patients with diabetes mellitus but without arterial hypertension (group 2, match criteria: ETDRS stage of retinopathy). In all subjects fluorescein angiograms were performed with a scanning laser ophthalmoscope. Macular capillary blood velocity (CBV), perifoveal intercapillary area (PIA), the coefficient of variation of both parameters, the area of the foveal avascular zone (FAZ), and the arteriovenous passage time (AVP) were assessed by digital image analysis.
RESULTS—Systolic and diastolic blood pressures were significantly increased in the patients with arterial hypertension (systolic p=0.0008; diastolic p=0.03). Neither dynamic measures (AVP: 1.64 (0.49) seconds (group 1), 1.72 (0.58) seconds (group 2); CBV: 1.98 (0.39) mm/s (group 1), 2.09 (0.43) mm/s (group 2)) nor morphological measures (PIA: 7985 (3137) µm2 (group 1), 8338 (3376) µm2 (group 2); FAZ: 0.319 (0.206) mm2 (group 1), 0.363 (0.237) mm2 (group 2)) were significantly different between the two groups of diabetic patients.
CONCLUSION—Arterial hypertension did not result in more severe macular capillary dropout than diabetes without hypertension. This might be explained by the fact that most of the patients were being treated with antihypertensive drugs.

 PMID:11090480

  12. Henle Fiber Layer Phase Retardation Changes Associated With Age-Related Macular Degeneration

    PubMed Central

    VanNasdale, Dean A.; Elsner, Ann E.; Peabody, Todd D.; Kohne, Kimberly D.; Malinovsky, Victor E.; Haggerty, Bryan P.; Weber, Anke; Clark, Christopher A.; Burns, Stephen A.

    2015-01-01

    Purpose. To quantify and compare phase retardation amplitude and regularity associated with the Henle fiber layer (HFL) between nonexudative AMD patients and age-matched controls using scanning laser polarimetry (SLP) imaging. Methods. A scanning laser polarimeter was used to collect 15 × 15° macular-centered images in 25 patients with nonexudative AMD and 25 age-matched controls. Raw image data were used to compute macular phase retardation maps associated with the HFL. Consecutive, annular regions of interest from 0.5 to 3.0° eccentricity, centered on the fovea, were used to generate intensity profiles from phase retardation data and analyzed with two complementary techniques: a normalized second harmonic frequency (2f) of the fast Fourier Transform (FFT) analysis and a curve fitting analysis using a 2f sine function. Paired t-tests were used to compare the normalized 2f FFT magnitude at each eccentricity between the two groups, the eccentricity that yielded the maximum normalized 2f FFT between paired individuals across the two groups, and curve fitting RMS error at each eccentricity between the two groups. Results. Normalized 2f FFT components were lower in the AMD group at each eccentricity, with no difference between the two groups in the maximum normalized 2f FFT component eccentricity. The root-mean-square (RMS) error from curve fitting was significantly higher in the AMD group. Conclusions. Phase retardation changes in the central macula indicate loss and/or structural alterations to central cone photoreceptors in nonexudative AMD patients. Scanning laser polarimetry imaging is a noninvasive method for quantifying cone photoreceptor changes associated with central macular disease. PMID:25525166

  13. Individualized Treatment of Neovascular Age-Related Macular Degeneration: What are Patients Gaining? Or Losing?

    PubMed Central

    Stewart, Michael W.

    2015-01-01

    The widespread use of drugs that bind diffusible vascular endothelial growth factor (VEGF) has revolutionized the treatment of neovascular age-related macular degeneration (AMD). The pivotal ranibizumab and aflibercept registration trials featured monthly intravitreal injections for 12 months, during which visual acuities and macular edema rapidly improved for the first 3 months and modest gains or stabilization continued until the primary endpoint. In many subsequent trials, patients were evaluated monthly and treated as-needed (PRN) according to the results of visual acuity (VA) testing, fundus examinations and optical coherence tomography scans. Compared to monthly-treated control groups, PRN treated patients require fewer injections during the first year but they also experience smaller VA gains (1–3 letters). A small number of prospective trials that directly compared monthly with PRN therapy showed that VA gains with discontinuous therapy lag slightly behind those achieved with monthly injections. Physicians recognize that monthly office visits with frequent intraocular injections challenge patients’ compliance, accrue high drug and professional service costs, and clog office schedules with frequently returning patients. To decrease the numbers of both office visits and anti-VEGF injections without sacrificing VA gains, physicians have embraced the treat-and-extend strategy. Treat-and-extend has not been studied as rigorously as PRN but it has become popular among both vitreoretinal specialists and patients. Despite the possible risks associated with discontinuous therapy (decreased VA and increased macular fluid), most physicians individualize treatment (PRN or treat-and-extend) for the majority of their patients. This review chapter explores the many advantages of individualized therapy, while balancing these against suboptimal responses due to the decreased frequency of anti-VEGF injections. PMID:26239466

  14. Individualized Treatment of Neovascular Age-Related Macular Degeneration: What are Patients Gaining? Or Losing?

    PubMed

    Stewart, Michael W

    2015-01-01

    The widespread use of drugs that bind diffusible vascular endothelial growth factor (VEGF) has revolutionized the treatment of neovascular age-related macular degeneration (AMD). The pivotal ranibizumab and aflibercept registration trials featured monthly intravitreal injections for 12 months, during which visual acuities and macular edema rapidly improved for the first 3 months and modest gains or stabilization continued until the primary endpoint. In many subsequent trials, patients were evaluated monthly and treated as-needed (PRN) according to the results of visual acuity (VA) testing, fundus examinations and optical coherence tomography scans. Compared to monthly-treated control groups, PRN treated patients require fewer injections during the first year but they also experience smaller VA gains (1-3 letters). A small number of prospective trials that directly compared monthly with PRN therapy showed that VA gains with discontinuous therapy lag slightly behind those achieved with monthly injections. Physicians recognize that monthly office visits with frequent intraocular injections challenge patients' compliance, accrue high drug and professional service costs, and clog office schedules with frequently returning patients. To decrease the numbers of both office visits and anti-VEGF injections without sacrificing VA gains, physicians have embraced the treat-and-extend strategy. Treat-and-extend has not been studied as rigorously as PRN but it has become popular among both vitreoretinal specialists and patients. Despite the possible risks associated with discontinuous therapy (decreased VA and increased macular fluid), most physicians individualize treatment (PRN or treat-and-extend) for the majority of their patients. This review chapter explores the many advantages of individualized therapy, while balancing these against suboptimal responses due to the decreased frequency of anti-VEGF injections.

  15. Circulating vitamin D concentration and age-related macular degeneration: Systematic review and meta-analysis.

    PubMed

    Annweiler, Cedric; Drouet, Morgane; Duval, Guillaume T; Paré, Pierre-Yves; Leruez, Stephanie; Dinomais, Mickael; Milea, Dan

    2016-06-01

    Vitamin D may be involved in ocular function in older adults, but there is no current consensus on a possible association between circulating concentrations of 25-hydroxyvitamin D (25OHD) and the occurrence of age-related macular degeneration (AMD). Our objective was to systematically review and quantitatively assess the association of circulating 25OHD concentration with AMD. A Medline search was conducted in November 2015, with no date limit, using the MeSH terms "Vitamin D" OR "Vitamin D deficiency" OR "Ergocalciferols" OR 'Cholecalciferol' combined with "Age-related macular degeneration" OR "Macular degeneration" OR "Retinal degeneration" OR "Macula lutea" OR "Retina". Fixed and random-effects meta-analyses were performed to compute (i) standard mean difference in 25OHD concentration between AMD and non-AMD patients; (ii) AMD risk according to circulating 25OHD concentration. Of the 243 retrieved studies, 11 observational studies-10 cross-sectional studies and 1 cohort study-met the selection criteria. The number of participants ranged from 65 to 17,045 (52-100% women), and the number with AMD ranged from 31 to 1440. Circulating 25OHD concentration was 15% lower in AMD compared with non-AMD on average. AMD was inversely associated with the highest 25OHD quintile compared with the lowest (summary odds ratio (OR)=0.83 [95%CI:0.71-0.97]), notably late AMD (summary OR=0.47 [95%CI:0.28-0.79]). Circulating 25OHD<50nmol/L was also associated with late-stage AMD (summary OR=2.18 [95%CI:1.34-3.56]), an association that did not persist when all categories of AMD were considered (summary OR=1.26 [95%CI:0.90-1.76]). In conclusion, this meta-analysis provides evidence that high 25OHD concentrations may be protective against AMD, and that 25OHD concentrations below 50nmol/L are associated with late AMD. PMID:27105707

  16. Vestibular dysfunction, altered macular structure and trait localization in A/J inbred mice.

    PubMed

    Vijayakumar, Sarath; Lever, Teresa E; Pierce, Jessica; Zhao, Xing; Bergstrom, David; Lundberg, Yunxia Wang; Jones, Timothy A; Jones, Sherri M

    2015-04-01

    A/J mice develop progressive hearing loss that begins before 1 month of age and is attributed to cochlear hair cell degeneration. Screening tests indicated that this strain also develops early onset vestibular dysfunction and has otoconial deficits. The purpose of this study was to characterize the vestibular dysfunction and macular structural pathology over the lifespan of A/J mice. Vestibular function was measured using linear vestibular evoked potentials (VsEPs). Macular structural pathology was evaluated using light microscopy, scanning electron microscopy, transmission electron microscopy, confocal microscopy and Western blotting. Individually, vestibular functional deficits in mice ranged from mild to profound. On average, A/J mice had significantly reduced vestibular sensitivity (elevated VsEP response thresholds and smaller amplitudes), whereas VsEP onset latency was prolonged compared to age-matched controls (C57BL/6). A limited age-related vestibular functional loss was also present. Structural analysis identified marked age-independent otoconial abnormalities in concert with some stereociliary bundle defects. Macular epithelia were incompletely covered by otoconial membranes with significantly reduced opacity and often contained abnormally large or giant otoconia as well as normal-appearing otoconia. Elevated expression of key otoconins (i.e., otoconin 90, otolin and keratin sulfate proteoglycan) ruled out the possibility of reduced levels contributing to otoconial dysgenesis. The phenotype of A/J was partially replicated in a consomic mouse strain (C57BL/6J-Chr 17(A/J)/NaJ), thus indicating that Chr 17(A/J) contained a trait locus for a new gene variant responsible to some extent for the A/J vestibular phenotype. Quantitative trait locus analysis identified additional epistatic influences associated with chromosomes 1, 4, 9 and X. Results indicate that the A/J phenotype represents a complex trait, and the A/J mouse strain presents a new model for the

  17. South Asian diabetic macular oedema treated with ranibizumab (ADMOR)-real-life experience.

    PubMed

    Ghanchi, F; Hazel, C A

    2016-01-01

    PURPOSE Diabetic macular oedema (DMO) is a leading cause for visual impairment in the working age population in the UK. Ranibizumab has been shown to be effective in treatment of DMO in studies based on mainly Caucasian populations. This study reports the 12-month outcome in a cohort of South Asian subjects with DMO treated with ranibizumab.MethodsDMO in 51 eyes of 41 South Asian patients was treated with ranibizumab 0.5 mg according to the modified DRCRnet protocol I. Visual acuity (VA) and central macular thickness (CMT) were recorded at baseline, 3, 6, and 12 months. Results were compared for eyes with different baseline visual acuities and different baseline macular thicknesses.RESULTS Over the 12-month period, the mean ETDRS VA increased from 55.3±13.4 letters to 63.8±15.2 letters for all eyes. At 12 months, 70.6% eyes gained 5 or more letters acuity and 17.6% eyes gained 15 letters or more. During the same period, the mean CMT decreased from 532±129 to 318±136 μm. Eyes that had received previous laser treatments had a mean letter gain of 9.2 letters, compared with 8.5 for all eyes at 12 months.CONCLUSIONS Ranibizumab 0.5 mg is safe and effective at reversing vision loss due to DMO in patients of South Asian origin at 12 months. Ranibizumab treatment appears to be effective in patients with longstanding DMO who received prior laser treatments. Further studies are needed to define the long-term outcome in patients of different ethnicity and DMO.

  18. Macular thickness changes evaluated with spectral domain optical coherence tomography after uncomplicated phacoemulsification

    PubMed Central

    Gharbiya, M; Cruciani, F; Cuozzo, G; Parisi, F; Russo, P; Abdolrahimzadeh, S

    2013-01-01

    Purpose To determine macular thickness changes after uncomplicated cataract surgery using spectral domain optical coherence tomography (OCT). Methods This was a prospective non-randomized, clinical study. Data were analysed for 40 healthy patients undergoing uneventful phacoemulsification. OCT measurements were performed before surgery and postoperatively at day 1, week 1 and 2, and month 1, 2, 3, and 6. The retinal map was divided into central point thickness (CPT), central 1-mm subfield (CSF), and two peripheral ring areas with diameters of 3 and 6 mm. Fellow eyes were used as controls. Retinal thickness change between the operated and fellow eyes were compared using unpaired t-test. Correlations were analysed using the Spearman or the Pearson analysis. Results There was a progressive significant increase in retinal thickness of the operated eyes compared with the fellow eyes, with a peak at 1 month (P<0.0001) for the 3- and 6-mm areas and a peak at 2 months for CPT and CSF (P=0.01 and P<0.0001, respectively). At 6 months, retinal thickness was still significantly increased only in the peripheral areas (P<0.0001). There was no significant correlation between macular thickness changes and preoperative factors (age, axial length, anterior chamber depth, posterior vitreous detachment, best-corrected visual acuity), intraoperative factors (length of surgery, effective phaco time, phaco energy) or BCVA change. Conclusions The present study demonstrated a significant increase in macular thickness up to 6 months after uncomplicated cataract surgery. The most important finding was the regional pattern of retinal thickening with an early involvement of the parafoveal area. PMID:23449512

  19. Autosomal Recessive Retinitis Pigmentosa with Early Macular Affectation Caused by Premature Truncation in PROM1

    PubMed Central

    Permanyer, Jon; Navarro, Rafael; Friedman, James; Pomares, Esther; Castro-Navarro, Joaquín; Marfany, Gemma; Swaroop, Anand

    2010-01-01

    Purpose. To identify the genetic basis of a large consanguineous Spanish pedigree affected with autosomal recessive retinitis pigmentosa (arRP) with premature macular atrophy and myopia. Methods. After a high-throughput cosegregation gene chip was used to exclude all known RP and Leber congenital amaurosis (LCA) candidates, genome-wide screening and linkage analysis were performed. Direct mutational screening identified the pathogenic mutation, and primers were designed to obtain the RT-PCR products for isoform characterization. Results. Mutational analysis detected a novel homozygous PROM1 mutation, c.869delG in exon 8 cosegregating with the disease. This variant causes a frameshift that introduces a premature stop codon, producing truncation of approximately two-thirds of the protein. Analysis of PROM1 expression in the lymphocytes of patients, carriers, and control subjects revealed an aberrant transcript that is degraded by the nonsense-mediated decay pathway, suggesting that the disease is caused by the absence of the PROM1 protein. Three (s2, s11 and s12) of the seven alternatively spliced isoforms reported in humans, accounted for 98% of the transcripts in the retina. Given that these three contained exon 8, no PROM1 isoform is expected in the affected retinas. Conclusions. A remarkable clinical finding in the affected family is early macular atrophy with concentric spared areas. The authors propose that the hallmark of PROM1 truncating mutations is early and severe progressive degeneration of both rods and cones and highlight this gene as a candidate of choice to prioritize in the molecular genetic study of patients with noncanonical clinical peripheral and macular affectation. PMID:20042663

  20. Circulating vitamin D concentration and age-related macular degeneration: Systematic review and meta-analysis.

    PubMed

    Annweiler, Cedric; Drouet, Morgane; Duval, Guillaume T; Paré, Pierre-Yves; Leruez, Stephanie; Dinomais, Mickael; Milea, Dan

    2016-06-01

    Vitamin D may be involved in ocular function in older adults, but there is no current consensus on a possible association between circulating concentrations of 25-hydroxyvitamin D (25OHD) and the occurrence of age-related macular degeneration (AMD). Our objective was to systematically review and quantitatively assess the association of circulating 25OHD concentration with AMD. A Medline search was conducted in November 2015, with no date limit, using the MeSH terms "Vitamin D" OR "Vitamin D deficiency" OR "Ergocalciferols" OR 'Cholecalciferol' combined with "Age-related macular degeneration" OR "Macular degeneration" OR "Retinal degeneration" OR "Macula lutea" OR "Retina". Fixed and random-effects meta-analyses were performed to compute (i) standard mean difference in 25OHD concentration between AMD and non-AMD patients; (ii) AMD risk according to circulating 25OHD concentration. Of the 243 retrieved studies, 11 observational studies-10 cross-sectional studies and 1 cohort study-met the selection criteria. The number of participants ranged from 65 to 17,045 (52-100% women), and the number with AMD ranged from 31 to 1440. Circulating 25OHD concentration was 15% lower in AMD compared with non-AMD on average. AMD was inversely associated with the highest 25OHD quintile compared with the lowest (summary odds ratio (OR)=0.83 [95%CI:0.71-0.97]), notably late AMD (summary OR=0.47 [95%CI:0.28-0.79]). Circulating 25OHD<50nmol/L was also associated with late-stage AMD (summary OR=2.18 [95%CI:1.34-3.56]), an association that did not persist when all categories of AMD were considered (summary OR=1.26 [95%CI:0.90-1.76]). In conclusion, this meta-analysis provides evidence that high 25OHD concentrations may be protective against AMD, and that 25OHD concentrations below 50nmol/L are associated with late AMD.

  1. Fruits and vegetables that are sources for lutein and zeaxanthin: the macular pigment in human eyes

    PubMed Central

    Sommerburg, O.; Keunen, J.; Bird, A.; van Kuijk, F. J G M

    1998-01-01

    BACKGROUND—It has been suggested that eating green leafy vegetables, which are rich in lutein and zeaxanthin, may decrease the risk for age related macular degeneration. The goal of this study was to analyse various fruits and vegetables to establish which ones contain lutein and/or zeaxanthin and can serve as possible dietary supplements for these carotenoids.
METHODS—Homogenates of 33 fruits and vegetables, two fruit juices, and egg yolk were used for extraction of the carotenoids with hexane. Measurement of the different carotenoids and their isomers was carried out by high performance liquid chromatography using a single column with an isocratic run, and a diode array detector.
RESULTS—Egg yolk and maize (corn) contained the highest mole percentage (% of total) of lutein and zeaxanthin (more than 85% of the total carotenoids). Maize was the vegetable with the highest quantity of lutein (60% of total) and orange pepper was the vegetable with the highest amount of zeaxanthin (37% of total). Substantial amounts of lutein and zeaxanthin (30-50%) were also present in kiwi fruit, grapes, spinach, orange juice, zucchini (or vegetable marrow), and different kinds of squash. The results show that there are fruits and vegetables of various colours with a relatively high content of lutein and zeaxanthin.
CONCLUSIONS—Most of the dark green leafy vegetables, previously recommended for a higher intake of lutein and zeaxanthin, have 15-47% of lutein, but a very low content (0-3%) of zeaxanthin. Our study shows that fruits and vegetables of various colours can be consumed to increase dietary intake of lutein and zeaxanthin.

 Keywords: age related macular degeneration; carotenoids; dietary intake; macular pigment PMID:9828775

  2. 3-D components of a biological neural network visualized in computer generated imagery. I - Macular receptive field organization

    NASA Technical Reports Server (NTRS)

    Ross, Muriel D.; Cutler, Lynn; Meyer, Glenn; Lam, Tony; Vaziri, Parshaw

    1990-01-01

    Computer-assisted, 3-dimensional reconstructions of macular receptive fields and of their linkages into a neural network have revealed new information about macular functional organization. Both type I and type II hair cells are included in the receptive fields. The fields are rounded, oblong, or elongated, but gradations between categories are common. Cell polarizations are divergent. Morphologically, each calyx of oblong and elongated fields appears to be an information processing site. Intrinsic modulation of information processing is extensive and varies with the kind of field. Each reconstructed field differs in detail from every other, suggesting that an element of randomness is introduced developmentally and contributes to endorgan adaptability.

  3. Progression of Idiopathic Eruptive Macular Pigmentation in a Girl from Childhood to Adolescence: Case Report and Literature Review.

    PubMed

    Tsai, Wen-Chien; Lan, Jui; Lee, Chih-Hung

    2016-09-01

    A 14-year-old girl developed brownish round macules and patches over the face, trunk, and proximal limbs with extensive progression since she was 7 years old. Electron microscopy examination revealed an increase in the number and maturity of melanosomes in basal and suprabasal keratinocytes, although the number of melanocytes was within the normal range. A diagnosis of idiopathic eruptive macular pigmentation was made. We describe the unusual disease progression of this case of idiopathic eruptive macular pigmentation, which was thought to be self-limited.

  4. Living together with age-related macular degeneration: An interpretative phenomenological analysis of sense-making within a dyadic relationship.

    PubMed

    Burton, Amy E; Shaw, Rachel L; Gibson, Jonathan M

    2015-10-01

    In this article, we present an idiographic analysis of a couple's experience of living and coming to terms with age-related macular degeneration. Interpretative phenomenological analysis was used to explore three joint interviews, conducted over an 18-month period, with a married couple (aged 82 and 77 years) both living with age-related macular degeneration. Three themes are discussed: the disruption of vision impairment, managing mutual deterioration and resilience through togetherness. We discuss the existential challenges of vision impairment and consider the applicability of Galvin and Todres' typology of well-being as a means of understanding well-being in older adults.

  5. Imaging polarimetry in patients with neovascular age-related macular degeneration.

    PubMed

    Elsner, Ann E; Weber, Anke; Cheney, Michael C; VanNasdale, Dean A; Miura, Masahiro

    2007-05-01

    Imaging polarimetry was used to examine different components of neovascular membranes in age-related macular degeneration. Retinal images were acquired with a scanning laser polarimeter. An innovative pseudocolor scale, based on cardinal directions of color, displayed two types of image information: relative phases and magnitudes of birefringence. Membranes had relative phase changes that did not correspond to anatomical structures in reflectance images. Further, membrane borders in depolarized light images had significantly higher contrasts than those in reflectance images. The retinal birefringence in neovascular membranes indicates optical activity consistent with molecular changes rather than merely geometrical changes. PMID:17429494

  6. Optical coherence tomography aspect of crystalline macular dystrophy in Sjögren-Larsson syndrome.

    PubMed

    Bhallil, Salima; Chraibi, Fouad; Andalloussi, Idriss Benatiya; Tahri, Hicham

    2012-10-01

    Sjögren-Larsson syndrome is an autosomal-recessive disease caused by a deficiency of the microsomal fatty aldehyde dehydrogenase enzyme. The syndrome is defined by congenital ichthyosis, spasticity, mental retardation and ocular features. We report the case of a 10-year-old boy presenting with bilateral visual impairment and photophobia. Fundus examination showed a mark of yellow-white refractile, perifoveal crystals in each eye. Optical coherence tomography (OCT) detected focal reflective structures corresponding to clinically visible intraretinal crystals and macular macrocystoids space. This case is presented to highlight the ocular findings and to evaluate the contribution of OCT in the study of the fovea anatomic changes.

  7. Macular pigmentation complicating irritant contact dermatitis and viral warts in Laugier-Hunziker syndrome.

    PubMed

    Bhoyrul, B; Paulus, J

    2016-04-01

    Laugier-Hunziker syndrome (LHS) is a rare acquired disorder characterized by macu-lar pigmentation of the lips and oral mucosa, with frequent longitudinal melanonychia. Involvement of other areas, such as the genitalia and fingers, has rarely been described. LHS is a benign condition with no known systemic manifestations. We report the case of a woman who developed melanotic macules on her fingers and elbow 16 years after the onset of pigmentation of her lips. This unusual feature of LHS in our patient was associated with irritant contact dermatitis and viral warts. Only two cases of an association with an inflammatory dermatosis have been reported previously in the literature.

  8. Cone photopigment in older subjects: decreased optical density in early age-related macular degeneration

    NASA Astrophysics Data System (ADS)

    Elsner, Ann E.; Burns, Stephen A.; Weiter, John J.

    2002-01-01

    We measured changes to cone photoreceptors in patients with early age-related macular degeneration. The data of 53 patients were compared with normative data for color matching measurements of long- and middle-wavelength-sensitive cones in the central macula. A four-parameter model quantified cone photopigment optical density and kinetics. Cone photopigment optical density was on average less for the patients than for normal subjects and was uncorrelated with visual acuity. More light was needed to reduce the photopigment density by 50% in the steady state for patients. These results imply that cone photopigment optical density is reduced by factors other than slowed kinetics.

  9. Overstaying their welcome: defective CX3CR1 microglia eyed in macular degeneration.

    PubMed

    Chen, Jing; Connor, Kip M; Smith, Lois E H

    2007-10-01

    Age-related macular degeneration (AMD), the most common cause of blindness in the elderly, is characterized by degeneration of the macula and can lead to loss of fine color vision. Alterations in inflammatory and immune system pathways, which arise from genetic differences, predispose individuals to AMD. Yet the mechanism of disease progression with respect to inflammation is not fully understood. In this issue of the JCI, the study by Combadière and colleagues shows that CX3C chemokine receptor 1-deficient (CX3CR1-deficient) mice have abnormal microglia that accumulate beneath the retina and contribute to the progression of AMD. PMID:17909623

  10. Genetic variants in the complement system predisposing to age-related macular degeneration: a review.

    PubMed

    Schramm, Elizabeth C; Clark, Simon J; Triebwasser, Michael P; Raychaudhuri, Soumya; Seddon, Johanna M; Atkinson, John P

    2014-10-01

    Age-related macular degeneration (AMD) is a major cause of visual impairment in the western world. It is characterized by the presence of lipoproteinaceous deposits (drusen) in the inner layers of the retina. Immunohistochemistry studies identified deposition of complement proteins in the drusen as well as in the choroid. In the last decade, genetic studies have linked both common and rare variants in genes of the complement system to increased risk of development of AMD. Here, we review the variants described to date and discuss the functional implications of dysregulation of the alternative pathway of complement in AMD.

  11. Fractal-Based Oscillation of Macular Arteriogenesis and Dropout During Progressive Diabetic Retinopathy

    NASA Technical Reports Server (NTRS)

    Radharkrishnan, Krishnan; Kaiser, Peter K.

    2011-01-01

    By both fractal (D1) and branching (Lv) analysis, macular arterial density oscillated with progression from mild NPDR to PDR. Results are consistent with out study reported recently for the entire arterial and venous branching trees within 50 degree FAs by VESGEN generational branching analysis. Current and previous results are important for advances in early-stage regenerative DR therapies, for which reversal of DR progression to a normal vessel density may be possible. For example, potential use of regenerative angiogenesis stimulators to reverse vascular dropout during mild and severe NPDR is not indicated for treatment of moderate NPDR.

  12. [Notalgia paresthetica, "posterior pigmented pruritic patch" and macular amyloidosis. Three stages of a disease].

    PubMed

    Cerroni, L; Kopera, D; Soyer, H P; Kerl, H

    1993-12-01

    We report on nine cases of notalgia paresthetica, a cutaneous condition that has rarely been described in the dermatological literature and is characterized by localized pruritus, burning and hyperesthesia and/or paresthesia on the back. Histological and immunohistochemical studies have not clarified the pathogenesis of this disease. Several factors might be involved in various cases, including increased cutaneous innervation and neuropathy. The so-called posterior pigmented pruritic patch and macular amyloidosis may be considered as progressive evolutional stages of notalgia paresthetica. PMID:8113041

  13. Investigation of Spiral and Sweeping Holes

    NASA Technical Reports Server (NTRS)

    Thurman, Douglas; Poinsatte, Philip; Ameri, Ali; Culley, Dennis; Raghu, Surya; Shyam, Vikram

    2015-01-01

    Surface infrared thermography, hotwire anemometry, and thermocouple surveys were performed on two new film cooling hole geometries: spiral/rifled holes and fluidic sweeping holes. The spiral holes attempt to induce large-scale vorticity to the film cooling jet as it exits the hole to prevent the formation of the kidney shaped vortices commonly associated with film cooling jets. The fluidic sweeping hole uses a passive in-hole geometry to induce jet sweeping at frequencies that scale with blowing ratios. The spiral hole performance is compared to that of round holes with and without compound angles. The fluidic hole is of the diffusion class of holes and is therefore compared to a 777 hole and Square holes. A patent-pending spiral hole design showed the highest potential of the non-diffusion type hole configurations. Velocity contours and flow temperature were acquired at discreet cross-sections of the downstream flow field. The passive fluidic sweeping hole shows the most uniform cooling distribution but suffers from low span-averaged effectiveness levels due to enhanced mixing. The data was taken at a Reynolds number of 11,000 based on hole diameter and freestream velocity. Infrared thermography was taken for blowing rations of 1.0, 1.5, 2.0, and 2.5 at a density ration of 1.05. The flow inside the fluidic sweeping hole was studied using 3D unsteady RANS.

  14. More Hidden Black Hole Dangers

    NASA Technical Reports Server (NTRS)

    Wanjek, Christopher

    2003-01-01

    Black holes such as GRO J1655-40 form from collapsed stars. When stars at least eight times more massive than our Sun exhaust their fuel supply, they no longer have the energy to support their tremendous bulk. These stars explode as supernovae, blasting their outer envelopes into space. If the core is more than three times the mass of the Sun, it will collapse into a singularity, a single point of infinite density.Although light cannot escape black holes, astronomers can see black holes by virtue of the hot, glowing gas often stolen from a neighboring star that orbits these objects. From our vantage point, the light seems to flicker. The Rossi Explorer has recorded this flickering (called quasiperiodic oscillations, or QPOs) around many black holes. QPOs are produced by gas very near the innermost stable orbit the closest orbit a blob of gas can maintain before falling pell-mell into the black hole. As gas whips around the black hole at near light speed, gravity pulls the gas in one direction, then another, adding to the flickering. The QPO is related to the speed and size of this orbit and the mass of the black hole.

  15. Superconducting electron and hole lenses

    NASA Astrophysics Data System (ADS)

    Cheraghchi, H.; Esmailzadeh, H.; Moghaddam, A. G.

    2016-06-01

    We show how a superconducting region (S), sandwiched between two normal leads (N), in the presence of barriers, can act as a lens for propagating electron and hole waves by virtue of the so-called crossed Andreev reflection (CAR). The CAR process, which is equivalent to Cooper pair splitting into two N electrodes, provides a unique possibility of constructing entangled electrons in solid state systems. When electrons are locally injected from an N lead, due to the CAR and normal reflection of quasiparticles by the insulating barriers at the interfaces, sequences of electron and hole focuses are established inside another N electrode. This behavior originates from the change of momentum during electron-hole conversion beside the successive normal reflections of electrons and holes due to the barriers. The focusing phenomena studied here are fundamentally different from the electron focusing in other systems, such as graphene p-n junctions. In particular, due to the electron-hole symmetry of the superconducting state, the focusing of electrons and holes is robust against thermal excitations. Furthermore, the effects of the superconducting layer width, the injection point position, and barrier strength are investigated on the focusing behavior of the junction. Very intriguingly, it is shown that by varying the barrier strength, one can separately control the density of electrons or holes at the focuses.

  16. Black Hole Grabs Starry Snack

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Poster Version

    This artist's concept shows a supermassive black hole at the center of a remote galaxy digesting the remnants of a star. NASA's Galaxy Evolution Explorer had a 'ringside' seat for this feeding frenzy, using its ultraviolet eyes to study the process from beginning to end.

    The artist's concept chronicles the star being ripped apart and swallowed by the cosmic beast over time. First, the intact sun-like star (left) ventures too close to the black hole, and its own self-gravity is overwhelmed by the black hole's gravity. The star then stretches apart (middle yellow blob) and eventually breaks into stellar crumbs, some of which swirl into the black hole (cloudy ring at right). This doomed material heats up and radiates light, including ultraviolet light, before disappearing forever into the black hole. The Galaxy Evolution Explorer was able to watch this process unfold by observing changes in ultraviolet light.

    The area around the black hole appears warped because the gravity of the black hole acts like a lens, twisting and distorting light.

  17. Black Holes and Quasiblack Holes in Einstein-Maxwell Theory

    NASA Astrophysics Data System (ADS)

    Meinel, Reinhard; Breithaupt, Martin; Liu, Yu-Chun

    2015-01-01

    Continuous sequences of asymptotically flat solutions to the Einstein-Maxwell equations describing regular equilibrium configurations of ordinary matter can reach a black hole limit. For a distant observer, the spacetime becomes more and more indistinguishable from the metric of an extreme Kerr-Newman black hole outside the horizon when approaching the limit. From an internal perspective, a still regular but non-asymptotically flat spacetime with the extreme Kerr-Newman near-horizon geometry at spatial infinity forms at the limit. Interesting special cases are sequences of Papapetrou-Majumdar distributions of electrically counterpoised dust leading to extreme Reissner-Nordström black holes and sequences of rotating uncharged fluid bodies leading to extreme Kerr black holes.

  18. Black holes and Higgs stability

    NASA Astrophysics Data System (ADS)

    Tetradis, Nikolaos

    2016-09-01

    We study the effect of primordial black holes on the classical rate of nucleation of AdS regions within the standard electroweak vacuum. We find that the energy barrier for transitions to the new vacuum, which characterizes the exponential suppression of the nucleation rate, can be reduced significantly in the black-hole background. A precise analysis is required in order to determine whether the the existence of primordial black holes is compatible with the form of the Higgs potential at high temperature or density in the Standard Model or its extensions.

  19. Black Holes: A Traveler's Guide

    NASA Astrophysics Data System (ADS)

    Pickover, Clifford A.

    1998-03-01

    BLACK HOLES A TRAVELER'S GUIDE Clifford Pickover's inventive and entertaining excursion beyond the curves of space and time. "I've enjoyed Clifford Pickover's earlier books . . . now he has ventured into the exploration of black holes. All would-be tourists are strongly advised to read his traveler's guide." -Arthur C. Clarke. "Many books have been written about black holes, but none surpass this one in arousing emotions of awe and wonder towards the mysterious structure of the universe." -Martin Gardner. "Bucky Fuller thought big. Arthur C. Clarke thinks big, but Cliff Pickover outdoes them both." -Wired. "The book is fun, zany, in-your-face, and refreshingly addictive." -Times Higher Education Supplement.

  20. Quantum mechanics of black holes.

    PubMed

    Witten, Edward

    2012-08-01

    The popular conception of black holes reflects the behavior of the massive black holes found by astronomers and described by classical general relativity. These objects swallow up whatever comes near and emit nothing. Physicists who have tried to understand the behavior of black holes from a quantum mechanical point of view, however, have arrived at quite a different picture. The difference is analogous to the difference between thermodynamics and statistical mechanics. The thermodynamic description is a good approximation for a macroscopic system, but statistical mechanics describes what one will see if one looks more closely.