Science.gov

Sample records for partial-thickness macular hole

  1. Effect of 1partial thickness actuation on stress concentration reduction near a hole

    NASA Technical Reports Server (NTRS)

    Sensharma, P. K.; Kadivar, M. H.; Haftka, R. T.

    1994-01-01

    Recently, there has been much interest in adaptive structures that can respond to a varying environment by changing their properties. Piezoelectric materials and shape memory alloys (SMA) are often used as partial thickness actuators to create such adaptivity by applied energy, usually electric curent. These actuators can be used to inducce strains in a structure and reduce stresses in regions of high stress concentration. Two of the present authors show that axisymmetric actuation strains applied troughout the thickness of a plate with a hole can reduce the stress concentration factor (SCF) in an isotropic plate from 3 to 2. However, in most cases actuators are expected to be bonded to or embedded in the plate, so that the actuation strains are applied in the actuators and not directly in the plate. The objective of this note is to show that such partial-thickness actuation cannot be used to reduce the stress concentration factor with axisymmetric actuations strain distribution.

  2. [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.

  3. Differentiating full thickness macular holes from impending macular holes and macular pseudoholes

    PubMed Central

    Tsujikawa, M.; Ohji, M.; Fujikado, T.; Saito, Y.; Motokura, M.; Ishimoto, I.; Tano, Y.

    1997-01-01

    AIMS—The reliability of scanning laser ophthalmoscope (SLO) microperimetry in differentiating full thickness macular holes from macular pseudoholes and impending macular holes was evaluated.
METHODS—106 eyes with the clinical diagnosis of full thickness macular holes, macular pseudoholes, and impending (stage 1) macular holes were examined for the presence of deep or relative scotoma using SLO microperimetry. The relation between these scotomas and the clinical diagnosis was studied.
RESULTS—Deep and relative scotomas were detected in all 57 eyes with clinically defined full thickness macular holes. In contrast, among 49 eyes diagnosed with macular pseudoholes or impending macular holes, no deep and only one relative scotoma was observed. The sensitivity of the presence of a deep scotoma as an indicator of the clinical diagnosis of a full thickness macular hole was 100% (57 of 57), and the specificity was 100% (49 of 49). The sensitivity of the presence of a relative scotoma was 100% (57 of 57) and the specificity was 98.0% (48 of 49).
CONCLUSION—With SLO microperimetry, full thickness macular holes can be precisely and objectively distinguished from other conditions that mimic macular holes.

 PMID:9059244

  4. Macular Hole Formation in Rhegmatogenous Retinal Detachment after Scleral Buckling

    PubMed Central

    Byon, Ik Soo; Kwon, Han Jo; Park, Gun Hyung; Park, Sung Who

    2014-01-01

    Purpose To describe early macular hole (MH) development in rhegmatogenous retinal detachment (RRD) after scleral buckling (SB) based on optical coherence tomography (OCT) findings. Methods The medical records and spectral domain OCT images of patients in whom MH developed after RRD repair were evaluated retrospectively. Results A postoperative MH was detected in five eyes that underwent SB during a 6-year period. All had fovea-off RRD without MH at the time of surgery. OCT showed partial loss of the inner retina with a preserved photoreceptor layer in early postoperative days. On average, 7 days (range,5 to 8 days) after surgery, outer retinal tissues disappeared, resulting in the full-thickness MH. Conclusions Serial OCT findings revealed that partial-thickness lamellar holes progressed to full-thickness MHs, which were formed by the degeneration of the outer retina in eyes with preceding loss of the glial cone in the fovea. PMID:25276077

  5. Macular holes: vitreoretinal relationships and surgical approaches.

    PubMed

    Bainbridge, J; Herbert, E; Gregor, Z

    2008-10-01

    Idiopathic full-thickness macular holes develop as a result of anteroposterior and tangential traction exerted by the posterior vitreous cortex at the fovea. Vitreoretinal relationships during the development of macular holes can be demonstrated in detail by ocular coherence tomography, facilitating an improved understanding of their pathogenesis and guiding clinical management. Surgical strategies for the repair of macular holes are designed to relieve vitreofoveal traction and to promote flattening and reapposition of the macular hole edges by intraocular gas tamponade. A period of face-down positioning postoperatively is conventionally advised. However, the evidence to support this recommendation is weak and practice varies considerably. Surgical removal of the inner limiting membrane (ILM) is advocated to ensure thorough removal of any tangential tractional components including any residual cortical vitreous. Current evidence suggests that ILM peeling can improve anatomical outcomes but the effect on visual function is less predictable; unsuccessful attempts to peel the ILM can be associated with poor visual outcome. The use of vital dyes can facilitate visualisation of the ILM and help achieve complete, atraumatic peeling. Indocyanine green dye can enable high rates of macular hole closure but has been associated with poorer visual outcomes suggesting a dose-dependent toxicity. Trypan blue dye offers an alternative that may have a more favourable risk profile. An improved understanding of vitreoretinal relationships may facilitate a tailored approach to surgery in individuals with macular holes. Vitrectomy to relieve anteroposterior traction is central in the management of all full-thickness holes. The use of long-acting gases, prolonged face-down positioning, and ILM peeling may be more valuable for larger holes, longstanding holes, and those that have failed to close following conventional surgery.

  6. 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.

  7. Current Management of Traumatic Macular Holes

    PubMed Central

    Grzybowski, Andrzej

    2017-01-01

    Traumatic macular hole (TMH) is not a rare clinical condition, especially in young population. Its prognosis is of complexity and uncertainty, with a relatively high rate of spontaneous closure in some cases. Modern vitrectomy surgery plays an important role in the treatment of TMH, although the functional outcomes may be compromised by the concomitant retinal pathologies. Decision-making about the time of vitrectomy, especially in pediatric patients, remains to be clarified further. PMID:28239490

  8. 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)

  9. Chronic Traumatic Giant Macular Hole Repair with Autologous Platelets

    PubMed Central

    Makkouk, Fuad; Picciani, Renata; Godley, Bernard; Elkeeb, Ahmed

    2017-01-01

    We report on the closure of a chronic posttraumatic giant macular hole. The patient presented with decreased vision in the left eye following blunt trauma 20 years prior. His dilated fundus examination revealed a 3000 um base-diameter full thickness macular hole. Surgical repair was performed with pars plana vitrectomy (PPV), internal limiting membrane peeling and autologous platelet concentrate (APC) injected over the macular hole. At one month follow-up, the macular hole had closed on exam and optical coherence tomography (OCT), and the patient reported subjective visual improvement. To our knowledge, this report presents the first case of a chronic giant macular hole successfully closed after undergoing surgery with adjuvant platelets therapy. PMID:28168133

  10. 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

  11. Macular hole closure following spontaneous release of vitreomacular traction.

    PubMed

    Ozgonul, Cem; Besirli, Cagri G

    2017-03-01

    We describe the temporal changes observed with spectral-domain optical coherence tomography (SD-OCT) in the left eye of a 65-year-old man who developed a stage 1 macular hole secondary to vitreomacular traction (VMT). After 1 month, VMT had resolved spontaneously with a complete posterior vitreous detachment. Following VMT resolution, macular hole demonstrated progressive improvement and outer retinal disruption recovered spontaneously. This report highlights the importance of observation before any intervention for cases of stage 1 macular hole associated with VMT.

  12. 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

  13. 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

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

    PubMed

    Abou Shousha, Mohsen Ahmed

    2016-01-01

    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.

  15. Spontaneous Closure of a Full-Thickness Macular Hole Associated with Proliferative Diabetic Retinopathy and Persistent Vitreomacular Traction

    PubMed Central

    Reinherz, Benjamin J.; Rubin, Jeffrey S.

    2016-01-01

    Diabetic retinopathy worsens the prognosis of macular holes compared to those of idiopathic etiology. While spontaneous closure of idiopathic macular holes is a well-documented phenomenon, spontaneous closure of macular holes associated with proliferative diabetic retinopathy is rare. We report a case of spontaneous closure of a macular hole associated with proliferative diabetic retinopathy and persistent vitreomacular traction. PMID:27099607

  16. Pneumoretinopexy in the treatment of retinal detachment with macular hole.

    PubMed

    Menchini, U; Scialdone, A; Visconti, C; Brancato, R

    1988-01-01

    Nine eyes of nine patients affected by retinal detachment with macular hole were treated with pneumoretinopexy and postoperative positioning. All the eyes were myopic (mean 13.3 d., sd 3.3), two were amblyopic and one was aphakic. The operative technique included eye softening and intravitreal SF6 gas injection only. Barrage laser photocoagulation was carried out after retinal reattachment. In seven eyes (77.8%) the retina reattached in a mean of three days and the visual acuity improved. No recurrences were observed after a mean of 11.6 months. No severe complications occurred. Vitreous flare was present in 44% and increase of floaters in 55% of the eyes. We believe that pneumoretinopexy can be employed as the first treatment in case of myopic retinal detachment with macular hole.

  17. Episcleral macular buckling for posterior retinal detachment in silicone oil filled eyes associated with myopic macular hole

    PubMed Central

    Tian, Jiao; Tang, Luo-Sheng; Guo, Xiao-Jian; Luo, Yong-Heng

    2013-01-01

    AIM To evaluate anatomical and visual outcomes of episcleral macular buckling (EMB) for posterior retinal detachment in silicone oil filled eyes associated with myopic macular hole. METHODS Five cases of EMB for initial failure of retinal reattachment after internal limiting membrane (ILM) peeling and silicone oil tamponade caused by myopic macular hole were retrospectively reviewed. A silicone sponge sutured directly across the macular region was performed on the silicone oil filled eyes. Silicone oil was removed no sooner than 1 month post-EMB. The duration of follow-up time after removal of silicone oil was more than 3 months. RESULTS Retinas of five eyes were all reattached at the last follow-up. The postoperative vision ranged from counting fingers to 0.08. CONCLUSION Anatomical results improved after EBM for posterior retinal detachment in silicone oil filled eyes associated with myopic macular hole, which was not evident for visual outcome. PMID:23638417

  18. Postoperative eccentric macular holes after vitrectomy and internal limiting membrane peeling.

    PubMed

    Brouzas, Dimitrios; Dettoraki, Maria; Lavaris, Anastasios; Kourvetaris, Dimitrios; Nomikarios, Nikolaos; Moschos, Marilita M

    2016-08-16

    The purpose of this study was to describe the incidence, clinical characteristics, and outcome of eccentric macular holes presenting after vitrectomy and internal limiting membrane (ILM) peeling for the treatment of macular pathology and discuss the pathogenesis of holes formation. A retrospective, noncomparative, interventional case-series study of five patients who developed eccentric macular holes postoperatively following vitrectomy in 198 consecutive patients who underwent ILM peeling for idiopathic macular hole and epiretinal membrane formation between 2008 and 2015. Five patients (2.5 %) developed full-thickness eccentric macular holes postoperatively. Three patients presented with a single eccentric macular hole, one patient had an eccentric hole after a failed idiopathic macular hole surgery and one patient developed four eccentric macular holes. The mean diameter of the holes was 584 μm (range 206-1317 μm) and the average time of holes formation after vitrectomy was 27.7 weeks (range 1-140 weeks). Postoperative best-corrected visual acuity ranged from "counting fingers" to 20/25. The eyes with the holes distant from the fovea had the best final visual acuity. No further intervention was attempted and no complications occurred. The mean follow-up time was 26.8 months. The postoperative macular holes after vitrectomy and ILM peeling were variable in number, size, and time of appearance but remained stable and were not associated with any complications. The pathogenesis of macular holes is most consistent with contraction of the residual ILM or secondary epimacular proliferation probably stimulated by ILM peeling.

  19. 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

  20. A New Sutureless Illuminated Macular Buckle Designed for Myopic Macular Hole Retinal Detachment

    PubMed Central

    Bedda, Ahmed M.; Lolah, Mohamed; Abd Al Shafy, Muhammad S.

    2017-01-01

    Purpose. To report the anatomic and visual results of a new sutureless illuminated macular buckle designed for patients with macular hole retinal detachment related to high myopia (MMHRD). Design. Prospective nonrandomized comparative interventional trial. Methods. Twenty myopic eyes of 20 patients (mean age, 51.4 years; range, 35–65 years) presenting with MMHRD with a posterior staphyloma, in whom the new buckle was used, were evaluated. The buckle used was assembled from a 5 mm wide sponge and a 7 mm wide silicone tire; it was fixed utilizing the sterile topical adhesive Histoacryl Blue (B Braun, TS1050044FP) which polymerizes in seconds upon being exposed to water-containing substances. The primary outcomes measured included aided visual acuity (BCVA) and optical coherence tomography (OCT) findings. The mean follow-up period was 6 months. Results. Postoperatively, the MH closure was identified by OCT in 8 (40%) eyes. The mean BCVA increased from 0.11 to 0.21 (p < 0.005). The axial length of the eyes included decreased from 30.5 mm preoperatively to 29.8 mm (p = 0.002) postoperatively. Conclusion. Preparation of the new sutureless macular buckle is simple and easy. Illumination of the terminal part of the buckle ensures proper placement. Histoacryl Blue is effective in fixing the buckle in its place for at least 6 months with no reported intra- or postoperative complications.

  1. Brilliant blue G-assisted peeling of the internal limiting membrane in macular hole surgery.

    PubMed

    Naithani, Prashant; Vashisht, Naginder; Khanduja, Sumeet; Sinha, Subijay; Garg, Satpal

    2011-01-01

    Dye-assisted internal limiting membrane (ILM) peeling and gas tamponade is the surgery of choice for idiopathic macular holes. Indocyanine green and trypan blue have been extensively used to stain the ILM. However, the retinal toxicity of indocyanine green and non-uniform staining with trypan blue has necessitated development of newer vital dyes. Brilliant blue G has recently been introduced as one such dye with adequate ILM staining and no reported retinal toxicity. We performed a 23-gauge pars plana vitrectomy with brilliant blue G-assisted ILM peeling in six patients with idiopathic macular holes, to assess the staining characteristics and short-term adverse effects of this dye. Adequate staining assisted in the complete removal of ILM and closure of macular holes in all cases. There was no evidence of intraoperative or postoperative dye-related toxicity. Brilliant blue G appears to be safe dye for ILM staining in macular hole surgery.

  2. Bilateral macular hole formation secondary to sclopetaria caused by shockwaves transmitted by a posterior vector: case report

    PubMed Central

    2010-01-01

    Background Sclopetaria is a rare ophthalmic finding in trauma Case Presentation This is a report of a patient who developed macular holes from sclopetaria induced by indirect trauma. A 22-year-old male, suffered a gunshot wound that passed behind his eyes, resulting in bilateral macular hole formation Conclusion To our knowledge, this is the first reported case in which trauma posterior to the globes caused bilateral macular hole formation PMID:20298610

  3. Visual function assessment and metamorphopsia after macular hole surgery.

    PubMed

    Wittich, Walter; Overbury, Olga; Kapusta, Michael A; Faubert, Jocelyn

    2005-11-01

    The purpose of this study was to develop a new resolution acuity measure for patients after macular hole surgery. Fifty eyes of 44 patients who had undergone successful treatment were tested. Visual acuity was measured with the Snellen, Early Treatment of Diabetic Retinopathy Study and Landolt-C charts. A Line Resolution Test was performed as part of their follow-up exam where a vertical line was presented. Participants were categorized by their perception of the line as solid, bent or broken. The line could be distorted into a sine-wave pattern in order to determine the participants' detection threshold for the distortion. Chart acuities did not differ among the three groups, as categorized by their line perception. Only the distortion measure was sensitive enough to differentiate the solid- from the broken-line group. The distortion measure assesses resolution power of the macula in smaller increments than acuity charts. This hyperacuity approach is more appropriate in the assessment of functional outcome after microsurgery.

  4. A surgical technique to protect the macular hole in indocyanine green-assisted vitrectomy.

    PubMed

    Saito, Masaaki; Iida, Tomohiro

    2006-01-01

    To prevent indocyanine green (ICG) toxicity during macular hole repair, a surgical technique was designed in which the hole is protected by a viscoelastic material before injecting ICG to stain the internal limiting membrane. The area covered by the viscoelastic material was not stained by ICG. The internal limiting membrane was peeled without difficulty by taking advantage of the ICG stain outlining it. After surgery, all holes closed and the postoperative outcomes were favorable. Only a small amount of residual ICG remained in the macular area. This surgical technique does not interfere with internal limiting membrane peeling and reduces the residual ICG postoperatively.

  5. 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

  6. A novel episcleral macular buckling: wire-strengthened sponge exoplant for recurrent macular hole and retinal detachment in high myopic eyes.

    PubMed

    Mortada, Hassan A

    2013-01-01

    The purpose would be to describe and evaluate a novel technique of episcleral macular buckling in postvitrectomy recurrent macular hole retinal detachment in highly myopic eyes. A 7mm silicone sponge strengthened with a U-shaped 0.5mm orthodontics stainless steel wire fed along its length and hand-bent to produce L-shaped buckle of appropriate shape and length, is used. The episcleral macular buckling has performed on 15 highly myopic eyes (axial length > 30mm) with recurrent macular hole retinal detachment following silicone oil removal. Buckle localization has been performed by manipulating the long arm of the exoplant, under direct internal visualization, scleral marking and suturing. Successful retinal reattachment with improvement in visual acuity achieved in all 15 eyes. Closure of the macular holes was confirmed by Optical Coherence Tomography. The anatomical and functional outcomes of this new technique of macular buckling appears to provide an effective and feasible means of retinal reattachment and hole closure in postvitrectomy recurrent macular hole detachment in highly myopic eyes.

  7. A Novel Episcleral Macular Buckling: Wire-Strengthened Sponge Exoplant for Recurrent Macular Hole and Retinal Detachment in High Myopic Eyes

    PubMed Central

    Mortada, Hassan A.

    2013-01-01

    The purpose would be to describe and evaluate a novel technique of episcleral macular buckling in postvitrectomy recurrent macular hole retinal detachment in highly myopic eyes. A 7mm silicone sponge strengthened with a U-shaped 0.5mm orthodontics stainless steel wire fed along its length and hand-bent to produce L-shaped buckle of appropriate shape and length, is used. The episcleral macular buckling has performed on 15 highly myopic eyes (axial length > 30mm) with recurrent macular hole retinal detachment following silicone oil removal. Buckle localization has been performed by manipulating the long arm of the exoplant, under direct internal visualization, scleral marking and suturing. Successful retinal reattachment with improvement in visual acuity achieved in all 15 eyes. Closure of the macular holes was confirmed by Optical Coherence Tomography. The anatomical and functional outcomes of this new technique of macular buckling appears to provide an effective and feasible means of retinal reattachment and hole closure in postvitrectomy recurrent macular hole detachment in highly myopic eyes. PMID:24600635

  8. 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

  9. Epiretinal Proliferation Associated with Macular Hole and Intraoperative Perifoveal Crown Phenomenon

    PubMed Central

    Son, Gisung; Lee, Ji Shin; Lee, Suchan

    2016-01-01

    Purpose To discuss the unique morphology and origin of epiretinal proliferation associated with macular hole (EPMH) occasionally observed in full-thickness macular hole (FT-MH) or lamellar hole (LH) and to introduce the perifoveal crown phenomenon encountered when removing this unusual proliferative tissue. Methods Sixteen patients showing EPMH in spectral domain-optical coherence tomography were selected from 212 patients diagnosed with MH, LH, FT-MH, impending MH, macular pseudohole, or epiretinal membrane between January 2013 and December 2014. Of the 212 patients included for clinical analysis, 33, 23, 11, 7, and 190 exhibited LH, FT-MH, impending MH, macular pseudohole, and epiretinal membrane, respectively. We reviewed visual acuity, macular morphology, and clinical course. Surgical specimens were analyzed histologically. Results EPMH presented as an amorphous proliferation starting from the defective inner/outer segment (IS/OS) junction covering the inner macula surface. Among the 16 patients with EPMH, 11 underwent vitrectomy, and all exhibited the intraoperative perifoveal crown phenomenon. EPMH tissue was sampled in three patients, one of whom had more tissue removed than intended and showed delayed recovery in visual acuity. Despite hole closure, IS/OS junction integrity was not successfully restored in four of 11 patients. Five patients were followed-up without surgical intervention. Visual acuity slightly decreased in three patients and did not change in one patient, while the remaining patient was lost during follow-up. Among the three perifoveal crown tissues obtained, two were successfully analyzed histologically. Neither tissue showed positivity to synaptophysin or S-100 protein, but one showed positivity to cytokeratin protein immunohistochemical staining. Conclusions EPMH exhibited a distinct but common configuration in spectral domain-optical coherence tomography. An epithelial proliferation origin is plausible based on its configuration and

  10. Evaluation of Macular Retinal Ganglion Cell-Inner Plexiform Layer Thickness after Vitrectomy with Internal Limiting Membrane Peeling for Idiopathic Macular Holes

    PubMed Central

    Velázquez-Villoria, Álvaro; Zapata, Miguel A.; Figueroa, Marta S.; Suárez-Leoz, Marta; Arrevola, Luis; Teijeiro, María-Ángeles; García-Layana, Alfredo

    2014-01-01

    Purpose. To evaluate macular retinal ganglion cell-inner plexiform layer (GCIPL) thickness changes after Brilliant Blue G-assisted internal limiting membrane peeling for idiopathic macular hole repair using a high-resolution spectral-domain optical coherence tomography (SD-OCT). Methods. 32 eyes from 32 patients with idiopathic macular holes who underwent vitrectomy with internal limiting membrane peeling between January 2011 and July 2012 were retrospectively analyzed. GCIPL thickness was measured before surgery, and at one month and at six months after surgery. Values obtained from automated and semimanual SD-OCT segmentation analysis were compared (Cirrus HD-OCT, Carl Zeiss Meditec, Dublin, CA). Results. No significant differences were found between average GCIPL thickness values between preoperative and postoperative analysis. However, statistical significant differences were found in GCIPL thickness at the temporal macular quadrants at six months after surgery. Quality measurement analysis performed by automated segmentation revealed a significant number of segmentation errors. Semimanual segmentation slightly improved the quality of the results. Conclusion. SD-OCT analysis of GCIPL thickness found a significant reduction at the temporal macular quadrants at 6 months after Brilliant Blue G-assisted internal limiting membrane peeling for idiopathic macular hole. PMID:25110679

  11. Silicone Oil Reinjection without Macular Buckling for Treatment of Recurrent Myopic Macular Hole Retinal Detachment after Silicone Oil Removal

    PubMed Central

    Ghoraba, Hammouda Hamdy; Elgouhary, Sameh Mohamed; Mansour, Hosam Osman

    2014-01-01

    Purpose. To evaluate the efficacy of silicone oil (S.O) reinjection without macular buckling for treatment of recurrent myopic macular hole retinal detachment (MHRD) after silicone oil removal. Methods. A retrospective consecutive interventional study from medical reports on cases of myopic MHRD. Fifty-three eyes of 51 patients underwent silicone oil removal after successful repair of MHRD were reviewed. The main outcomes were the retinal status after silicone oil removal and management of recurrent cases. Results. The rate of recurrent RD (Re RD) after silicone oil removal was 11.3% (6 out of 53 eyes). One case refused any other interference. In the remaining 5 eyes, 4 eyes (80%) could be reattached by S.O re-injection and one eye (20%) developed Re RD after S.O re-injection. Range of followup after management of recurrence was 5–53 months (mean 18.7 months). Conclusions. This case series concluded that the risk factors for recurrent RD after silicone oil removal from cases of myopic MHRD were high myopia, open flat MH, and large posterior staphyloma. Revision of vitrectomy and S.O re-injection can reattach most of recurrent cases. PMID:24672706

  12. “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. PMID:27800199

  13. "Brilliant Blue G" and "Membrane Blue Dual" assisted vitrectomy for macular hole.

    PubMed

    Kovacević, Damir; Mance, Tea Caljkusić; Markusić, Vedran

    2011-09-01

    The aim of this study is to evaluate vital dyes "Brilliant Blue G" (BBG) and "Membrane Blue Dual" (MBD) for intraoperative staining of the inner limiting membrane (ILM) during vitrectomy for macular hole (MH). Retrospective, comparative case series on 18 eyes with macular holes who underwent "23 and 25 gauge" pars plana vitrectomy. Main outcome measurements were staining intensity and characteristics, visual acuity, visual field, OCT measurements and complications over a period of 6 months. With the help of BBG and MBD successfully was removed complete ILM in 14 eyes. Postoperative visual acuity was improved in 12 patients, unchanged in 2 patients and worse in 4 patients. Central retinal thickness showed significant postoperative reduction with closure of macular hole. OCT values range were from -10 to -250 microm. No visual field defects and no adverse effects were found. BBG and MBD successfully identificate internal limiting membrane during vitrectomy for MH. Good anatomical and functional results are achieved with the use of both vital dyes.

  14. Morphision: A method for subjective evaluation of metamorphopsia in patients with unilateral macular pathology (i.e., full thickness macular hole and epiretinal membrane)

    PubMed Central

    Ugarte, Marta; Shunmugam, Manoharan; Laidlaw, D Alistair H; Williamson, Tom H

    2013-01-01

    Background: Lack of clinical tests to quantify spatial components of distortion in patients with full thickness macular holes (FTMH) and epiretinal membranes (ERM). Aim: To develop a test for subjective evaluation of visual distortion in the central visual field around fixation in patients with unilateral FTMH or ERM. Settings and Design: Prospective case-control study carried out at tertiary referral center. Materials and Methods: Twenty-five patients with unilateral macular disease (13 macular epiretinal membranes, 12 full-thickness macular holes), and nine controls (without ocular pathology) underwent ophthalmological examination with logMAR ETDRS visual acuity, near vision and contrast sensitivity assessed. Macular optical coherence tomography and metamorphopsia assessment using Morphision test was also carried out. This test consists of a set of modified Amsler charts for detection, identification, and subjective quantification of visual distortion in the central visual field around fixation. Morphision test content and construct validity, and reliability (test-retest method) were evaluated. Sixteen patients completed an unstructured survey on test performance and preference. Results: Every patient with unilateral FTMH or ERM identified a particular chart using Morphision test (content validity). None of the normal subjects without symptoms of metamorphopsia identified any distortion (construct validity). Test-retest showed a 100% consistency for frequency and 67% for amplitude. The mean amplitude difference between measurements was 0.02 degrees (SD = 0.038). The coefficient of repeatability was 0.075. There was a correlation between Morphision amplitude score and visual acuity and contrast sensitivity, individually. Conclusions: Morphision test allowed detection and subjective quantification of metamorphopsia in the clinical setting in our patients with unilateral macular epiretinal membranes and full thickness macular holes. PMID:24008785

  15. Classification of Full-Thickness Traumatic Macular Holes by Optical Coherence Tomography

    PubMed Central

    Huang, Jingjing; Liu, Xing; Wu, Ziqiang; Lin, Xiaofeng; Li, Mei; Dustin, Laurie; Sadda, Srinivas

    2009-01-01

    Purpose To describe morphological features of traumatic macular holes (TMH) on optical coherence tomography (OCT) and to correlate them with clinical findings. Methods Seventy-three consecutive patients diagnosed with full-thickness TMH involving the fovea underwent complete ophthalmic evaluation followed by horizontal and vertical line scans using the StratusOCT. Retinal thickness at the edges of the holes, apical and basal diameters, and various clinical parameters were recorded. The approximate apical and basal areas and eccentricities of the holes were calculated. Morphological parameters were correlated with clinical findings. Results Based on OCT findings, TMHs were classified into 5 morphological types with varying average retinal thicknesses, apical areas, and basal areas. Patients who presented more than 90 days after injury had greater average retinal thickness (p=0.03) and apex areas (p=0.002) compared to those who presented within 90 days. Older patients developed more circular holes, i.e. less eccentricity of the apex (p=0.04) and base (p=0.01). Interestingly, none of the morphological parameters investigated in the current study correlated with visual acuity. Patients who presented later in the clinical course or who had greater average retinal thicknesses tended to have better vision (p=0.11 and p=0.07, respectively). Conclusions OCT evaluation may yield important insights into the pathogenesis and clinical findings of traumatic macular holes. PMID:19092730

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

    PubMed

    Steel, D H W; Lotery, A J

    2013-10-01

    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.

  17. 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

  18. Role of Tractional Forces and Internal Limiting Membrane in Macular Hole Formation: Insights from Intraoperative Optical Coherence Tomography

    PubMed Central

    Moisseiev, Elad; Yiu, Glenn

    2016-01-01

    We report the case of a 69-year-old patient who underwent vitrectomy for vitreomacular traction (VMT) and developed a postoperative macular hole that was observed 1 week after surgery. The hole did not close by in-office fluid-gas exchange alone, but was achieved after repeat surgery with internal limiting membrane (ILM) peeling. Intraoperative OCT (iOCT) images from the first surgery revealed an occult macular hole that formed after VMT release. We discuss how iOCT findings provide insight into the role of the ILM in macular hole formation and emphasize the importance of carefully inspecting iOCT images in real time to avoid missing small but important findings. PMID:27721786

  19. Macular Hole

    MedlinePlus

    ... Courier services use: Rockville, MD 20852) 301-451-2020 Research at NEI Office of the Scientific Director ... Eye Disease Education Program Glaucoma Education Program Low Vision Education Program Hispanic/Latino Program Vision and Aging ...

  20. Microperimetric Biofeedback Training Improved Visual Acuity after Successful Macular Hole Surgery

    PubMed Central

    Ueda-Consolvo, Tomoko; Otsuka, Mitsuya; Hayashi, Yumiko; Ishida, Masaaki; Hayashi, Atsushi

    2015-01-01

    Purpose. To evaluate the efficacy of setting a preferred retinal locus relocation target (PRT) and performing Macular Integrity Assessment (MAIA) biofeedback training in patients showing insufficient recovery of best corrected visual acuity (BCVA) despite successful closure of an idiopathic macular hole (MH). Methods. Retrospective interventional case series. Nine eyes of 9 consecutive patients with the decimal BCVA of less than 0.6 at more than 3 months after successful MH surgery were included. A PRT was chosen based on MAIA microperimetry and the patients underwent MAIA biofeedback training. BCVA, reading speed, fixation stability, and 63% bivariate contour ellipse area (BCEA) were evaluated before and after the training. Statistical analysis was carried out using paired Student's t-test. Results. PRT was chosen on the nasal side of the closed MH fovea in 8 patients. After the MAIA training, BCVA improved in all patients. The mean logMAR value of BCVA significantly improved from 0.33 to 0.12 (p = 0.007). Reading speed improved in all patients (p = 0.29), fixation stability improved in 5 patients (p = 0.70), and 63% BCEA improved in 7 patients (p = 0.21), although these improvements were not statistically significant. Conclusion. MAIA biofeedback training improved visual acuity in patients with insufficient recovery of BCVA after successful MH surgery. PMID:26783452

  1. [Initial Clinical Experiences Using Ocriplasmin for the Treatment of Vitreomacular Traction with or without a Macular Hole].

    PubMed

    Lenk, J; Matthé, E; Ventzke, S; Pillunat, L E; Sandner, D

    2017-03-10

    Purpose In vitreomacular traction (VMT), there is abnormal adhesion between the vitreous cortex and the retina, especially in the fovea. Symptoms of VMT include metamorphopsia and a decrease in visual acuity. Since 2013, ocriplasmin (Jetrea®) has been approved for treatment of symptomatic vitreomacular traction with or without macular holes (≤ 400 µm). Methods We retrospectively examined twenty-three eyes of twenty-one patients who underwent intravitreal ocriplasmin treatment for symptomatic vitreomacular traction with or without macular holes. Best corrected visual acuity and central retinal thickness (CRT) were measured in advance and after ocriplasmin treatment. The numbers of resolved vitreomacular traction and closed macular holes were documented. Results Vitreomacular traction was resolved in eight of twenty-three eyes (34.8 %); in fifteen eyes (65.2 %) it was persistent and two of four macular holes were found closed. The average best corrected visual acuity was 0.39 ± 0.25 logMAR at baseline and 0.41 ± 0.24 logMAR at the first follow-up visit after injection (p = 0.613). The average CRT was 453.3 ± 172.7 µm at baseline, with a slight decrease to 412.0 ± 212 µm (p = 0.124). Conclusion Intravitreal injection of ocriplasmin appears is an experimental therapy in patients with symptomatic vitreomacular traction. Patient selection seems to be critically important for the therapeutic outcome, whereas greater age, specific VMT morphology and missing chromatopsia seem to be negative predictors.

  2. An Assessment of Vitreous Degeneration in Eyes with Vitreomacular Traction and Macular Holes.

    PubMed

    Ghadiali, Quraish; Zahid, Sarwar; Dolz-Marco, Rosa; Tan, Anna; Engelbert, Michael

    2017-01-01

    Purpose. To compare the stages of vitreous degeneration in patients with vitreomacular traction (VMT) and macular holes (MH). Methods. A retrospective study was performed analyzing stages of vitreous degeneration of eyes with VMT or MH using swept-source optical coherence tomography (SS-OCT) and spectral-domain optical coherence tomography (SD-OCT). An analogous review was performed on a control group of eyes with contralateral posterior vitreous detachments. Thirty-four eyes with VMT/MH and 39 control eyes were reviewed. Results. Twenty-seven VMT/MH eyes and 31 control eyes were included. Eyes with VMT/MH demonstrated significantly earlier stages of vitreous degeneration when compared to the control group (p = 0.048) despite significantly greater age (p = 0.032). Conclusions. Vitreoretinal interface disease is more often associated with a formed vitreous and an intact premacular bursa. This is contrary to previous assumptions implicating degeneration of vitreous as a precipitating factor of interface disease when in conjunction with abnormal vitreomacular separation.

  3. An Assessment of Vitreous Degeneration in Eyes with Vitreomacular Traction and Macular Holes

    PubMed Central

    Zahid, Sarwar; Tan, Anna

    2017-01-01

    Purpose. To compare the stages of vitreous degeneration in patients with vitreomacular traction (VMT) and macular holes (MH). Methods. A retrospective study was performed analyzing stages of vitreous degeneration of eyes with VMT or MH using swept-source optical coherence tomography (SS-OCT) and spectral-domain optical coherence tomography (SD-OCT). An analogous review was performed on a control group of eyes with contralateral posterior vitreous detachments. Thirty-four eyes with VMT/MH and 39 control eyes were reviewed. Results. Twenty-seven VMT/MH eyes and 31 control eyes were included. Eyes with VMT/MH demonstrated significantly earlier stages of vitreous degeneration when compared to the control group (p = 0.048) despite significantly greater age (p = 0.032). Conclusions. Vitreoretinal interface disease is more often associated with a formed vitreous and an intact premacular bursa. This is contrary to previous assumptions implicating degeneration of vitreous as a precipitating factor of interface disease when in conjunction with abnormal vitreomacular separation. PMID:28133544

  4. 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.

  5. Viscoat Assisted Inverted Internal Limiting Membrane Flap Technique for Large Macular Holes Associated with High Myopia

    PubMed Central

    Song, Zongming; Li, Mei; Liu, Junjie; Hu, Xuting; Hu, Zhixiang

    2016-01-01

    Purpose. To investigate the surgical outcomes of Viscoat® assisted inverted internal limiting membrane (ILM) flap technique for large macular holes (MHs) associated with high myopia. Design. Prospective, interventional case series. Methods. Fifteen eyes of 15 patients with high myopia underwent vitrectomy and Viscoat assisted inverted ILM flap technique to treat MH without RD. Patients were followed up over 6 months. The main outcome measures were MH closure evaluated by optical coherence tomography (OCT) and best-corrected visual acuities (BCVAs). Result. MH closure was observed in all eyes (100%) following the initial surgery. Type 1 closure was observed in 13 eyes (86.7%); type 2 closure was observed in the remaining 2 eyes (13.3%). Compared to the preoperative baseline, the mean BCVA (logarithm of the minimum angle of resolution) improved significantly at 3 months and 6 months after surgery (P = 0.025, 0.019, resp.). The final BCVA improved in 10 eyes (66.7%), remained unchanged in 3 eyes (20.0%), and worsened in 2 eyes (13.3%). Conclusion. Vitrectomy combined with Viscoat assisted inverted ILM flap technique is an effective treatment for large MHs in highly myopic eyes. It may increase the success rate of the initial surgery and enhance the anatomical and functional outcomes. PMID:27047686

  6. 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

  7. Internal Limiting Membrane Flap Techniques for the Repair of Large Macular Holes: a Short-Term Follow-up of Anatomical and Functional Outcomes.

    PubMed

    Guber, J; Lang, C; Valmaggia, C

    2017-02-01

    Background To evaluate the technique of inverted internal limiting membrane (ILM) flaps for the management of large macular holes and autologous ILM free flaps for non-closing macular holes. Patients and methods All macular holes were treated with pars plana vitrectomy and dual blue assisted ILM flap technique. The inverted ILM flap was created as a primary procedure for large macular holes (diameter > 400 µm). On the other hand, the free ILM flap technique was used as a secondary procedure for non-closing macular holes after failed initial standard procedure. SD-OCT images were taken to assess the anatomical outcome of surgery, while best corrected visual acuity (BCVA) was used to evaluate the functional outcome during a 2-month follow-up. Results All patients underwent successful planned manipulation of the ILM flap. In seven patients/eyes, an inverted ILM flap was created, in three patients/eyes a free ILM flap translocation was performed. All patients 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 some cases as early as one month after surgery. Functionally, in comparison to baseline, most of the patients showed improvements in BCVA of 1 to 2 lines at the first postoperative follow-up visit. Conclusions Inverted ILM flaps for large macular holes and free flaps for non-closing macular holes appear to be a safe and effective approach, with favourable short-term anatomical and functional results.

  8. 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

  9. Anteriorly Based Partial Thickness Sternocleidomastoid Muscle Flap Following Parotidectomy.

    PubMed

    Dalmia, Deepak; Behera, Sanjaya Kumar; Bhatia, Jas Simran Singh

    2016-03-01

    The anteriorly based partial thickness sternocleidomastoid (SCM) muscle flap is among the various methods described to correct parotidectomy defects, but its indications and limitations are not clearly demonstrated in several reports. This study was done to test the aesthetic outcome of this method, its indications and limitations. At Dr. Babasaheb Ambedkar Memorial hospital, Mumbai, 20 patients presenting with benign parotid tumors underwent parotidectomy. 16 underwent superficial parotidectomy and 3 underwent adequate parotidectomy, 1 had total parotidectomy. The anteriorly based partial thickness SCM muscle flap was used to correct the contour deformity and to prevent Frey syndrome. The aesthetic result was evaluated by assessing and scoring the overall appearance of the scar, the degree of symmetry of the reconstructed parotid region and the site of the donor muscle in comparison to their contralateral normal sides. The overall aesthetic appearance was good in 17 patients, and moderate in 3 patients. 17/20 patients had an overall deep satisfaction with the result. The residual hollowness following total parotidectomy defect and the poor quality of scars were the main reasons affecting the aesthetic outcome. Superficial parotidectomy through modified Blair's incision with immediate reconstruction with anteriorly based partial thickness SCM flap allows a satisfactory aesthetic outcome and minimal donor site morbidity. Scores of the above two parameters were accessed. Patients' satisfaction was assessed by patients questionnaire.

  10. 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

  11. Macular Hole Associated with Vogt-Koyanagi-Harada Disease at the Acute Uveitic Stage

    PubMed Central

    Mizuno, Masaharu; Fujinami, Kaoru; Watanabe, Ken; Akiyama, Kunihiko

    2015-01-01

    We describe a case with macular hole (MH) associated with Vogt-Koyanagi-Harada (VKH) disease. A 71-year-old Japanese woman presented with visual loss and headaches. The best-corrected visual acuity (BCVA) was 0.02 in the right eye (RE) and 0.1 in the left eye (LE). The patient was diagnosed with VKH based on circumferential choroidal detachments, multiple serous retinal detachments, and optic disc hyperemia. The multiple serous retinal detachments improved with high-dose corticosteroid therapy and gradual tapering. The BCVA was recovered to 1.2/0.7 in the RE/LE. Six weeks after the initial administration of steroid, vitreomacular traction was found by optical coherence tomography in the LE, which progressed to stage 4 MH with the BCVA of 0.2 in the LE. Twenty-three weeks after the initial treatment, vitrectomy was performed with the standard surgical procedures, including inner limiting membrane peeling around the fovea and air tamponade. The MH was closed successfully and the BCVA was 0.4 in the LE 5 weeks after the vitrectomy. This is the first report of a case with MH secondary to the acute uveitic stage of VKH. Successful closure of MH was achieved with the standard surgical intervention for an idiopathic MH. To conclude, at the early stage of VKH, there is a possibility of MH formation due to the rapid progress of vitreous traction following the inflammation, and the surgical procedure could be effective to resolve this secondary disorder. PMID:26483677

  12. 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

  13. Partial-thickness burn wounds healing by topical treatment

    PubMed Central

    Saeidinia, Amin; Keihanian, Faeze; Lashkari, Ardalan Pasdaran; Lahiji, Hossein Ghavvami; Mobayyen, Mohammadreza; Heidarzade, Abtin; Golchai, Javad

    2017-01-01

    Abstract Background: Burns are common event and associated with a high incidence of death, disability, and high costs. Centella asiatica (L.) is a medicinal herb, commonly growing in humid areas in several tropical countries that improve wound healing. On the basis of previous studies, we compared the efficacy of Centiderm versus silver sulfadiazine (SSD) in partial thickness burning patients. Methods: Study population comprised burn victims referred to Velayat Burning Hospital at Rasht, Iran. The intervention group received Centiderm and control group SSD cream. Burn wounds were treated once daily at home. All of the wounds were evaluated till complete healing occurred and at the admission, days 3, 7, 14 objective signs; visual acuity score (VAS) and subjective signs were recorded. Re-epithelialization time and complete healing days were recorded. We used random fixed block for randomization. The randomization sequence was created using the computer. Patients and burning specialist physician were blinded. Results: Seventy-five patients randomized into 2 groups; (40 patients: Centiderm group; 35 patients: SSD group). The mean age of them was 30.67 ± 9.91 years and 19 of them were male (31.7%). Thirty patients in Centiderm and 30 patients in SSD group were analyzed. All of objective and subjective signs and mean of re-epithelialization and complete healing were significantly better in Centiderm group rather than SSD group (P < 0.05). There was no infection in Centiderm group. Conclusions: We showed that use of Centiderm ointment not only improved the objective and subjective signs in less than 3 days, but also the re-epithelialization and complete healing rather than SSD without any infection in the subjects. PMID:28248871

  14. Complications of Macular Peeling

    PubMed Central

    Asencio-Duran, Mónica; Manzano-Muñoz, Beatriz; Vallejo-García, José Luis; García-Martínez, Jesús

    2015-01-01

    Macular peeling refers to the surgical technique for the removal of preretinal tissue or the internal limiting membrane (ILM) in the macula for several retinal disorders, ranging from epiretinal membranes (primary or secondary to diabetic retinopathy, retinal detachment…) to full-thickness macular holes, macular edema, foveal retinoschisis, and others. The technique has evolved in the last two decades, and the different instrumentations and adjuncts have progressively advanced turning into a safer, easier, and more useful tool for the vitreoretinal surgeon. Here, we describe the main milestones of macular peeling, drawing attention to its associated complications. PMID:26425351

  15. 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

  16. 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

  17. Clinical and histological evaluation of large macular hole surgery using the inverted internal limiting membrane flap technique

    PubMed Central

    Kase, Satoru; Saito, Wataru; Mori, Shohei; Saito, Michiyuki; Ando, Ryo; Dong, Zhenyu; Suzuki, Tomohiro; Noda, Kousuke; Ishida, Susumu

    2017-01-01

    Purpose The aims of this study were to analyze optical coherence tomography (OCT) imaging of large macular holes (MHs) treated with inverted internal limiting membrane (ILM) flap technique and to perform a histological examination of an ILM-like membrane tissue obtained during vitrectomy. Patients and methods This is a retrospective observational case study. Nine patients, comprising of five males and four females, showing large and myopic MHs, underwent pars plana vitrectomy (PPV) with inverted ILM flap technique assisted by brilliant blue G (BBG) staining. Ophthalmological findings including visual acuity and OCT were investigated based on medical records. Formalin-fixed paraffin-embedded tissue section of an ILM-like membrane was submitted for immunohistochemistry with glial fibrillary acidic protein (GFAP). Results ILM was clearly stained with BBG in eight patients, whereas the ILM in one case revealed no staining with BBG during PPV. Visual acuities improved to >0.2 LogMAR in six patients. The complete closure of MH following PPV with inverted ILM technique was eventually achieved in all patients determined by OCT imaging (100%). Only one patient showed recovery of ellipsoid zone and interdigitation zone following the surgery. Elongation of outer nuclear layer was noted in three eyes. The ILM-like membrane not stained with BBG histologically revealed an amorphous structure admixed with GFAP-positive mononuclear cell infiltration. Conclusion PPV with inverted ILM flap technique achieved 100% closure rates with favorable configuration at an initial surgery in large MHs. Our histopathological data also suggest that even BBG staining-negative membrane may be a useful material for autologous transplantation to the hole. PMID:28031697

  18. Changes in Inner and Outer Retinal Layer Thicknesses after Vitrectomy for Idiopathic Macular Hole: Implications for Visual Prognosis

    PubMed Central

    Hashimoto, Yuki; Saito, Wataru; Fujiya, Akio; Yoshizawa, Chikako; Hirooka, Kiriko; Mori, Shohei; Noda, Kousuke; Ishida, Susumu

    2015-01-01

    Purpose To investigate sequential post-operative thickness changes in inner and outer retinal layers in eyes with an idiopathic macular hole (MH). Methods Retrospective case series. Twenty-four eyes of 23 patients who had received pars plana vitrectomy (PPV) for the closure of MH were included in the study. Spectral domain optical coherence tomography C-scan was used to automatically measure the mean thickness of the inner and outer retinal layers pre-operatively and up to 6 months following surgery. The photoreceptor outer segment (PROS) length was measured manually and was used to assess its relationship with best-corrected visual acuity (BCVA). Results Compared with the pre-operative thickness, the inner layers significantly thinned during follow-up (P = 0.02), particularly in the parafoveal (P = 0.01), but not perifoveal, area. The post-operative inner layer thinning ranged from the ganglion cell layer to the inner plexiform layer (P = 0.002), whereas the nerve fiber layer was unaltered. Outer layer thickness was significantly greater post-operatively (P = 0.002), and especially the PROS lengthened not only in the fovea but also in the parafovea (P < 0.001). Six months after surgery, BCVA was significantly correlated exclusively with the elongated foveal PROS (R = 0.42, P = 0.03), but not with any of the other thickness parameters examined. Conclusions Following PPV for MH, retinal inner layers other than the nerve fiber layer thinned, suggestive of subclinical thickening in the inner layers where no cyst was evident pre-operatively. In contrast, retinal outer layer thickness significantly increased, potentially as a result of PROS elongation linking tightly with favorable visual prognosis in MH eyes. PMID:26291526

  19. miRNAs in the vitreous humor of patients affected by idiopathic epiretinal membrane and macular hole

    PubMed Central

    Ragusa, Marco; Barbagallo, Cristina; Longo, Antonio; Avitabile, Teresio; Uva, Maurizio G.; Bonfiglio, Vincenza; Toro, Mario D.; Caltabiano, Rosario; Mariotti, Cesare; Boscia, Francesco; Romano, Mario; Di Pietro, Cinzia; Barbagallo, Davide; Purrello, Michele; Reibaldi, Michele

    2017-01-01

    Purpose The aim of the present study was to assess the expression of miRNAs in the Vitreous Humor (VH) of patients with Macular Hole (MH) and Epiretinal Membrane (ERM) compared to a control group. Methods In this prospective, comparative study, 2-ml of VH was extracted from the core of the vitreous chamber in consecutive patients who underwent standard vitrectomy for ERM and MH. RNA was extracted and TaqMan® Low Density Arrays (TLDAs) were used to profile the transcriptome of 754 miRNAs. Results were validated by single TaqMan® assays. Finally, we created a biological network of differentially expressed miRNA targets and their nearest neighbors. Results Overall 10 eyes with MH, 16 eyes with idiopathic ERM and 6 controls were enrolled in the study. Profiling data identified 5 miRNAs differentially expressed in patients affected by MH and ERM with respect to controls. Four were downregulated (miR-19b, miR-24, miR-155, miR-451) and 1 was downregulated (miR-29a); TaqMan® assays of the VH of patients affected by MH and ERM, with respect to controls, showed that the most differentially expressed were miR-19b (FC -9.13, p:<0.00004), mir-24 (FC -7.52, p:<0.004) and miR-142-3p (FC -5.32, p:<0.011). Our network data showed that deregulation of differentially expressed miRNAs induces an alteration of several pathways associated with genes involved in both MH and ERM. Conclusion The present study suggests that disregulation of miR-19b, miR-24 and miR-142-3p, might be related to the alterations that characterize patients affected by MH and ERM. PMID:28328945

  20. Visual function and vision-related quality of life after vitrectomy for idiopathic macular hole: a 12mo follow-up study

    PubMed Central

    Duan, Hong-Tao; Chen, Song; Wang, Yue-Xin; Kong, Jia-Hui; Dong, Meng

    2015-01-01

    AIM To investigate the visual function and the relationship with vision-related quality of life (VRQOL) after macular hole repair surgery. METHODS Prospective case series. Thirty-six consecutive eyes in 36 patients who underwent pars plana vitrectomy (PPV) and internal limiting membrane (ILM) peeling were included. The 25-item National Eye Institute Visual Function Questionnaire (VFQ-25) was answered by the participants before and 3 and 12mo after operation. Follow-up visits examinations included best-corrected visual acuity (BCVA), clinical examination, and central macular thickness (CMT) measured by optical coherence tomography (OCT). RESULTS Macular-hole closure was achieved in 35 of 36 eyes (97.2%). At baseline and months 3 and 12, the logMAR BCVAs (mean±SD) were 1.15±0.47, 0.68±0.53 (P<0.0001 versus baseline), and 0.55±0.49 (P<0.001 versus baseline, P =0.273 versus month 3), respectively; the CMTs (µm) were 330±81, 244±62 (P<0.001 versus baseline), and 225±58 (P<0.001 versus baseline, P=0.222 versus month 3), respectively; the median preoperative VFQ-25 composite score of 73.50 (63.92-81.13) increased postoperatively to 85.50 (80.04-89.63) at 3mo (P<0.001) and 86.73(82.50-89.63) at 12mo (P<0.001) respectively. The improved BCVA was correlated with improvements in five subscales (r=-0.605 to -0.336, P<0.001 to P=0.046) at 12mo. CONCLUSION PPV with ILM peeling improved anatomic outcome, visual function, and VRQOL. The improved BCVA was an important factor related to the improved VRQOL. PMID:26309877

  1. Macular Hole Surgery with Internal Limiting Membrane Peeling Facilitated by Membrane-Blue® versus Membrane-Blue-Dual®: A Retrospective Comparative Study

    PubMed Central

    Shai, Daniel; Loewenstein, Anat

    2016-01-01

    Background. This study aims to compare the outcome of macular hole (MH) surgery with internal limiting membrane (ILM) peeling facilitated by two different vital dyes. Methods. This was a retrospective chart review. The group designated “group-MB” underwent pars plana vitrectomy with ILM peeling facilitated by Membrane-Blue (MB), whereas in “group-MBD,” the vital dye used was Membrane-Blue-Dual (MBD). Results. Seventy-four eyes comprised the study population: 53 in group-MB and 21 in group-MBD. There was no difference in the rate of macular hole closure in group-MB or group-MBD: 71.2% closed MHs compared to 66.7%, respectively (p = 0.7). Postoperative visual improvement was of a higher magnitude in the MBD group compared to the MB group: −0.34 ± 0.81 logMAR versus 0.01 ± 0.06 logMAR, respectively (p = 0.003). Conclusions. In this study, MBD led to better visual results that may be related to better staining characteristics or lesser toxicity compared to MB. PMID:28050275

  2. Long-Term Changes in Intraocular Pressure after Vitrectomy for Rhegmatogenous Retinal Detachment, Epi-Retinal Membrane, or Macular Hole

    PubMed Central

    Yamamoto, Kentaro; Iwase, Takeshi; Terasaki, Hiroko

    2016-01-01

    Purpose To determine the long-term changes in the intraocular pressure (IOP) following vitrectomy for rhegmatogenous retinal detachment (RRD), epiretinal membrane (ERM), and macular hole (MH), and to investigate the relationship between the retinal disease and the incidence of late-onset IOP elevation. Methods This was a retrospective, observational, comparative study. We reviewed the medical records of 54 eyes of 54 RRD patients, 117 eyes of 117 ERM patients, and 75 eyes of 75 MH patients who underwent 20-, 23- or 25-gauge vitrectomy. The IOPs before surgery and 1, 3, 6, and 12 months following vitrectomy, and also at the final visit (average, 23.95 months) were evaluated. We defined a significant increase in the IOP as an increase of ≥4 mmHg from the preoperative IOP, and this increase was taken to be a ‘death’ event for the Kaplan-Meier survival analyses. Results The mean follow-up period was not significantly different among the groups. The mean IOP at 3 (P = 0.001) and 12 (P = 0.011) months following the vitrectomy and at the final visit (P = 0.002) were significantly higher than that before the vitrectomy in the RRD group. The mean IOP in the RRD group was significant higher than that in the ERM group at 1 (P = 0.005), 3 (P = 0.009), and 12 (P = 0.013) months following vitrectomy, and at the final visit (P = 0.032). Kaplan-Meier survival analyses showed that the RRD group had a significantly higher risk of an IOP increase following vitrectomy than the other groups (P<0.001 by log-rank test). Multivariate logistic regression analyses showed that a preoperative diagnosis of RRD was the only risk factor that was significantly associated with a postoperative IOP elevation after excluding eyes with a low preoperative IOP (odds ratio, 3.208; P = 0.003). Conclusions A late-onset IOP elevation following vitrectomy was observed only in eyes that underwent RRD surgery. The elevation was probably caused by the specific characteristics and surgical procedures of

  3. Incidence and distribution of paravascular lamellar holes and their relationship with macular retinoschisis in highly myopic eyes using spectral-domain oct.

    PubMed

    Vela, José I; Sánchez, Fernando; Díaz-Cascajosa, Jesús; Mingorance, Ester; Andreu, David; Buil, José A

    2016-04-01

    The purpose of the study is to determine the incidence and distribution of paravascular lamellar holes (PLH) around retinal vessels in highly myopic eyes and their relationship with macular retinoschisis (MR). We examined 306 eyes of 178 patients with high myopia, performing multiple scans of the posterior pole within the retinal vascular arcades using spectral-domain OCT. Type of staphyloma was determined. PLH were divided into three groups: holes only (group 1), holes extending below vessels (group 2), and holes in an area of paravascular retinoschisis (group 3). OCT showed that 96/306 eyes (31.4 %) had PLH mainly along the infero-temporal arcade (39.9 %). Type V and IX staphylomas had a higher proportion of PLH in the infero-temporal arcade than other staphylomas. Group 3 eyes presented higher rates of myopia and staphyloma. MR was detected in 10/27 eyes (37 %) in Group 3, but only in 2/33 eyes (6.1 %) in Group 1. No MR was found in Group 2. PLH are relatively common in highly myopic eyes and mainly distributed in the inferior temporal arcade. Findings from this descriptive study suggest that distribution of PLH might be related to the type of staphyloma. Further studies are needed to evaluate the relevance of PLH in the pathogenesis of MR.

  4. Honey compared with silver sulphadiazine in the treatment of superficial partial-thickness burns.

    PubMed

    Malik, Kamran Ishaque; Malik, M A Nasir; Aslam, Azhar

    2010-10-01

    Burn injury is associated with a high incidence of death and disability; yet, its management remains problematic and costly. We conducted this clinical study to evaluate the efficacy of honey in the treatment of superficial and partial-thickness burns covering less than 40% of body surface area and compared its results with those of silver sulphadiazine (SSD). In this randomised comparative clinical trial, carried out Burn Center of POF Hospital, Wah Cantt, Pakistan, from May 2007 to February 2008, 150 patients of all ages having similar types of superficial and partial-thickness burns at two sites on different parts of body were included. Each patient had one burn site treated with honey and one treated with topical SSD, randomly. The rate of re-epithelialization and healing of superficial and partial-thickness burns was significantly faster in the sites treated with honey than in the sites treated with SSD (13·47 ± 4·06 versus 15·62 ± 4·40 days, respectively: P < 0·0001). The site treated with honey healed completely in less than 21 days versus 24 days for the site treated with SSD. Six patients had positive culture for Pseudomonas aeroginsa in honey-treated site, whereas 27 patients had positive culture in SSD-treated site. The results clearly showed greater efficacy of honey over SSD cream for treating superficial and partial-thickness burns.

  5. What Is Macular Edema?

    MedlinePlus Videos and Cool Tools

    ... Español Eye Health / Eye Health A-Z Macular Edema Sections What Is Macular Edema? What Causes Macular ... Edema Diagnosis Macular Edema Treatment What Is Macular Edema? Dec. 01, 2010 Macular edema is swelling or ...

  6. Macular hole formation and spontaneous closure after vitrectomy for rhegmatogenous retinal detachment documented by spectral-domain optical coherence tomography: Case report and literature review

    PubMed Central

    Kim, Jin Young; Park, Sung Pyo

    2015-01-01

    This case report describes macular hole (MH) formation and spontaneous closure after vitrectomy for rhegmatogenous retinal detachment (RRD) repair. A 58-year-old man referred with a macula-off superior RRD, in whom vitrectomy was performed. MH with vitreomacular traction (VMT) caused by the posterior vitreous cortex remnants developed 2 weeks after vitrectomy. Four weeks postoperatively, optical coherence tomography revealed resolution of the VMT and spontaneous closure of MH without providing any treatment. This is the first report of an MH formation and spontaneous closure after vitrectomy for RRD. This suggests that the VMT mediated by the posterior vitreous cortex remnants has an important role in the development of secondary MH. PMID:26655006

  7. 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

  8. Macular degeneration

    MedlinePlus Videos and Cool Tools

    ... 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.

  9. Steel Wool-Aided Dermabrasion of Deep Partial-Thickness Burns.

    PubMed

    Yontar, Yalcin; Coruh, Atilla; Dinc, Nadire; Kontas, Olgun

    2016-10-07

    Early tangential excision of the burn wound is essential for removal of necrotic tissue and promotion of burn wound healing process. However, the depth of the burn wound is not easily assessed during the tangential excision performed by hand-held dermatomes, and it may be possible to excise unburned vital dermis unnecessarily, which aids in primary epithelization of the burn wound by adnexal structures. We herein present early clinical results of steel wool-aided dermabrasion in patients with deep partial-thickness burns. This is a retrospective case study of 23 consecutive hospitalized patients with deep partial-thickness burns. All of the steel wool-aided dermabrasions were performed under general anesthesia within 48 hours after injury. Patients were excluded from the study if the admission was not within 24 hours after injury, and if the burn wound was entirely superficial partial- or full-thickness. Thirteen male and 10 female patients with a mean age of 26.2 ± 17.1 years were enrolled in the study. During the follow-up period, all of the patients had burn wounds primary epithelized on postburn day 15.1 ± 1.8, without any complications. None of the patients exhibited a mortal course, and redebridement or skin grafting of the previously dermabraded deep partial-thickness burn wounds were not required in any of the patients. Steel wool-aided dermabrasion is an easy, cost-effective, and reliable technique for the treatment of deep partial-thickness burns, which provides complete removal of necrotic tissue, preserves the vital dermis, reduces the requirement for skin grafting, and decreases length of hospital stay.

  10. Keratin-based products for effective wound care management in superficial and partial thickness burns injuries.

    PubMed

    Loan, Fiona; Cassidy, Sharon; Marsh, Clive; Simcock, Jeremy

    2016-05-01

    This n=40 cohort study on superficial and partial thickness burns compares novel keratin-based products with the standard products used at our facility. The keratin products are found to facilitate healing with minimal scarring, be well tolerated with minimal pain and itch, be easy to use for the health professional and be cost effective for the health care provider. For these reasons they are being adopted into use at our facility.

  11. New Innovations for Deep Partial-Thickness Burn Treatment with ACell MatriStem Matrix

    PubMed Central

    Kim, Justine S.; Kaminsky, Alexander J.; Summitt, J. Blair; Thayer, Wesley P.

    2016-01-01

    Objective: Burn injuries remain a large financial burden on the healthcare system. According to CDC statistics (2010), nonfatal and hospitalized burns in the U.S. cost $1.8 billion for an annual incidence of ∼486,000 cases. To date, no technique proves to be the ideal therapy of deep partial-thickness burns. In this study, we review a trial usage of ACell (ACell, Inc.) wound matrix on deep partial-thickness burns. Approach: Burn patients were admitted through the Vanderbilt Emergency Department. Three were consented to receive ACell therapy. Each patient suffered extremity burns, to which ACell MatriStem matrix was applied. Time to epithelialization and healing was monitored up to 1 month postintervention. Results: ACell MatriStem matrix use in deep partial-thickness burns enabled healing by 29 days on average without requiring autografts. The average total body surface area (TBSA) of injury was 7.2% with average TBSA treated with ACell equal to 2.5%. All burn sites underwent re-epithelialization after 5.6 days on average (range 4–7 days). Average length of stay after ACell placement totaled 2 days. All patients fully healed without the need for subsequent grafting or contracture development. No postoperative complications were noted. Innovation: To the extent of our knowledge, this is one of the first reported series to utilize ACell MatriStem product in deep partial-thickness extremity burns. Conclusion: Despite numerous products currently available for burn reconstruction, no one product embodies all the characteristics of an ideal graft. ACell biological extracellular matrix scaffolding appears promising, allowing for healing without use of an autograft. PMID:28078188

  12. Bilateral macular cysts following electric burn.

    PubMed

    Sony, Parul; Venkatesh, Pradeep; Tewari, Hem Kumar; Garg, Sat Pal

    2005-02-01

    A 28-year-old man presented with bilateral acute loss of vision following a high-voltage injury. The visual acuity was 6/36 in the right eye and 6/24 in the left eye. Fundus examination revealed a well-defined round lesion simulating a full thickness macular hole in the right eye and yellow deposits in the macular area in the left eye. Optical coherence tomography (OCT) showed bilateral macular cysts, with intact outer and inner retinal layers. At 1 month follow up, OCT showed a persistent macular cyst in the right eye with spontaneous resolution of the macular cyst along with visual improvement in the left eye.

  13. 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

  14. 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

  15. 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.

  16. [Macular dystrophies].

    PubMed

    Souied, E; Kaplan, J; Coscas, G; Soubrane, G

    2003-09-01

    Macular dystrophies are a group of hereditary disorders of the macula occurring in children or young adults. The most frequent in France will be presented in detail: Best disease, Stargardt macular dystrophy, cone dystrophy, X-linked retinoschisis, pattern dystrophy, and malattia leventinese. Molecular biology studies have now mapped and identified the genes involved in these macular dystrophies. Analysis of the features of fundus examination will lead to further examinations such as fluorescein angiography, indocyanine green angiography, optical coherent tomography, electroretinography, or electrooculography, in order to confirm the diagnosis. We will also present the differential diagnosis of each of these macular dystrophies.

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

    PubMed Central

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

    2012-01-01

    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). PMID:23396264

  18. Deep partial thickness burn blister fluid promotes neovascularization in the early stage of burn wound healing.

    PubMed

    Pan, Shin-Chen; Wu, Li-Wha; Chen, Chung-Lin; Shieh, Shyh-Jou; Chiu, Haw-Yen

    2010-01-01

    The effect of burn blister fluid in neovascularization during burn wound healing is unknown. Burn blister fluid, containing a large amount of chemokines, is thought to play a role in the early stage of neovascularization. This process includes angiogenesis and vasculogenesis. Because of different healing time of burn wounds, we hypothesized that neovascularization in superficial partial thickness burn (SPTB) and deep partial thickness burn (DPTB) wounds were different. The neovasculogenic effects of two different burn blister fluids were also different. We found Day 7 DPTB wounds had a significant increase in blood vessels compared with SPTB wounds by immunohistochemistry. DPTB blister fluid significantly promoted neovascularization via increasing endothelial cell proliferation, and migration and differentiation of circulating angiogenic cells relative to SPTB blister fluids. In the animal study, DPTB blister fluids markedly promoted new blood vessel formation compared with those from SPTB blister fluids using in vivo Matrigel plug assay. These results suggest that DPTB wounds require more new vessel formation than SPTB. Furthermore, the measurement of angiogenic activities in burn blister fluids serves as a possible tool for assessing burn wound status.

  19. 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).

  20. 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.

  1. 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.

  2. Multiple Graft Harvestings from Deep Partial-Thickness Scald Wounds Healed under the Influence of Weak Direct Current

    DTIC Science & Technology

    1990-01-01

    U.S.A. Multiple Graft Harvestings from Deep Partial-thickness Scald Wounds Healed under the Influence of Weak Direct Current CHI-SING CHU, M.D...healing, contraction, and hypertrophic ELECTE f scarring often limit the use of deep partial-thickness burn wounds as donor sites for split-thickness...with Weak Direct Current 1049 donor site healing with DC treatment, since such wounds also experience at least transient periods of ischemia . "The

  3. 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

  4. Comparisons of retinal nerve fiber layer thickness after indocyanine green, brilliant blue g, or triamcinolone acetonide-assisted macular hole surgery.

    PubMed

    Toba, Yoshiharu; Machida, Shigeki; Kurosaka, Daijiro

    2014-01-01

    Purpose. To compare the postoperative changes of the retinal nerve fiber layer (RNFL) thickness in patients with macular holes (MHs) treated with vitrectomy with indocyanine green- (ICG-), brilliant blue G- (BBG-), or triamcinolone acetonide- (TA-)assisted internal limiting membrane (ILM) peeling. Methods. Sixty-one eyes of 61 consecutive patients with MHs were studied. Each eye was randomly selected to undergo either ICG- (n = 18), BBG- (n = 21), or TA-assisted (n = 22) ILM peeling. The circumferential retinal nerve fiber layer (RNFL) thickness was determined by spectral-domain optical coherence tomography (SD-OCT) before and 1, 3, 6, 9, and 12 months postoperatively. The mean overall and the sectoral thicknesses of the RNFL were obtained for each group. Results. A transient increase of the RNFL thickness was seen in the mean overall and sectoral thicknesses except for the nasal/inferior sector at 1 month after surgery for the three groups. Then, the thickness gradually decreased and returned to the baseline level in all sectors except for the nasal/inferior sector. The differences in the RNFL thickness among the groups were not significant for at least 12 months postoperatively. Conclusions. The degree of change of the RNFL thickness was not significantly related to the type of vital stain used during MH surgery.

  5. 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.

  6. Acute discrimination between superficial-partial and deep-partial thickness burns in a preclinical model with laser speckle imaging.

    PubMed

    Crouzet, Christian; Nguyen, John Quan; Ponticorvo, Adrien; Bernal, Nicole P; Durkin, Anthony J; Choi, Bernard

    2015-08-01

    A critical need exists for a robust method that enables early discrimination between superficial-partial and deep-partial thickness burn wounds. In this study, we report on the use of laser speckle imaging (LSI), a simple, non-invasive, optical imaging modality, to measure acute blood flow dynamics in a preclinical burn model. We used a heated brass comb to induce burns of varying severity to nine rats and collected raw speckle reflectance images over the course of three hours after burn. We induced a total of 12 superficial-partial and 18 deep-partial thickness burn wounds. At 3h after burn we observed a 28% and 44% decrease in measured blood flow for superficial-partial and deep-partial thickness burns, respectively, and that these reductions were significantly different (p=0.00007). This preliminary data suggests the potential role of LSI in the clinical management of burn wounds.

  7. Assessment of Deep Partial Thickness Burn Treatment with Keratin Biomaterial Hydrogels in a Swine Model

    PubMed Central

    Poranki, D.; Goodwin, C.

    2016-01-01

    Partial thickness burns can advance to full thickness after initial injury due to inadequate tissue perfusion and increased production of inflammatory cytokines, which has been referred to as burn wound progression. In previous work, we demonstrated that a keratin biomaterial hydrogel appeared to reduce burn wound progression. In the present study, we tested the hypothesis that a modified keratin hydrogel could reduce burn wound progression and speed healing. Standardized burn wounds were created in Yorkshire swine and treated within 30 minutes with keratin hydrogel (modified and unmodified), collagen hydrogel, or silver sulfadiazine (SSD). Digital images of each wound were taken for area measurements immediately prior to cleaning and dressing changes. Wound tissue was collected and assessed histologically at several time points. Wound area showed a significant difference between hydrogels and SSD groups, and rates of reepithelialization at early time points showed an increase when keratin treatment was used compared to both collagen and SSD. A linear regression model predicted a time to wound closure of approximately 25 days for keratin hydrogel while SSD treatment required 35 days. There appeared to be no measurable differences between the modified and unmodified formulations of keratin hydrogels. PMID:28025638

  8. 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.

  9. [Application of high-frequency ultrasound in dermabrasion of patients with deep partial-thickness burns].

    PubMed

    Zang, C Y; Cao, Y Q; Xue, W J; Zhao, R; Zhang, M; Zhang, Y H; Feng, Z; Wang, Y B

    2017-02-20

    Objective: To investigate the application of high-frequency ultrasound in dermabrasion of patients with deep partial-thickness burns. Methods: Twenty-six patients with deep partial-thickness burns conforming to the study criteria were hospitalized in our unit from March 2015 to March 2016. Patients were all performed with dermabrasion. The structure of skin tissue and blood flow signals of uninjured side and wounds before dermabrasion, and those of wounds immediately post dermabrasion and on post dermabrasion day (PDD) 1, 3, 5, 7, 10, 14, and 21 were detected with high-frequency ultrasound, and the percentage of blood flow signals was calculated. According to the results of comparison between percentage of blood flow signals of wounds and that of normal skin before dermabrasion, patients were divided into no significant decrease group (NSD, n=19) and significant decrease group (SD, n=7). Wound healing time of patients in two groups was recorded. Data were processed with analysis of variance of repeated measurement, LSD test, t test and Chi-square test. The correlation between the percentage of blood flow signals of wounds before dermabrasion and wound healing time of 26 patients were analyzed by Spearman correlation analysis. Results: (1) Epidermis of normal skin of patients in two groups before dermabrasion showed continuous smooth linear hyperecho, which was stronger than that of dermis, and boundary of dermis and subcutaneous tissue showed stronger discontinuous linear echo than that of dermis, which gradually transited to subcutaneous tissue. In group NSD, epidermis of wound of patients before dermabrasion showed intermittent rough linear echo, which was weaker than that of normal skin epidermis, and there was no obvious abnormity of boundary between dermis and subcutaneous tissue. Immediately post dermabrasion and on PDD 1, no linear hyperecho of epidermis was observed, showing complete attrition of epidermis, and the echo of dermis and subcutaneous tissue had

  10. Effect of Extracorporeal Shock Wave Treatment on Deep Partial-Thickness Burn Injury in Rats: A Pilot Study

    PubMed Central

    Kamelger, Florian Stefan; Jeschke, Johannes; Piza-Katzer, Hildegunde

    2014-01-01

    Extracorporeal shock wave therapy (ESWT) enhances tissue vascularization and neoangiogenesis. Recent animal studies showed improved soft tissue regeneration using ESWT. In most cases, deep partial-thickness burns require skin grafting; the outcome is often unsatisfactory in function and aesthetic appearance. The aim of this study was to demonstrate the effect of ESWT on skin regeneration after deep partial-thickness burns. Under general anesthesia, two standardized deep partial-thickness burns were induced on the back of 30 male Wistar rats. Immediately after the burn, ESWT was given to rats of group 1 (N = 15), but not to group 2 (N = 15). On days 5, 10, and 15, five rats of each group were analyzed. Reepithelialization rate was defined, perfusion units were measured, and histological analysis was performed. Digital photography was used for visual documentation. A wound score system was used. ESWT enhanced the percentage of wound closure in group 1 as compared to group 2 (P < 0.05). The reepithelialization rate was improved significantly on day 15 (P < 0.05). The wound score showed a significant increase in the ESWT group. ESWT improves skin regeneration of deep partial-thickness burns in rats. It may be a suitable and cost effective treatment alternative in this type of burn wounds in the future. PMID:25431664

  11. 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 ...

  12. Wet Macular Degeneration

    MedlinePlus

    Wet macular degeneration Overview By Mayo Clinic Staff Wet macular degeneration is a chronic eye disease that causes blurred vision ... of the retina responsible for central vision. Wet macular degeneration is one of two types of age-related ...

  13. Dry Macular Degeneration

    MedlinePlus

    Dry macular degeneration Overview By Mayo Clinic Staff Dry macular degeneration is a common eye disorder among people over 65. ... vision in your direct line of sight. Dry macular degeneration may first develop in one eye and then ...

  14. Autologous tenocyte implantation, a novel treatment for partial-thickness rotator cuff tear and tendinopathy in an elite athlete.

    PubMed

    Wang, Allan W; Bauer, Stefan; Goonatillake, Matthew; Breidahl, William; Zheng, Ming-Hao

    2013-01-11

    Tendinopathy and small partial-thickness tears of the rotator cuff tendon are common presentations in sports medicine. No promising treatment has yet been established. Corticosteroid injections may improve symptoms in the short term but do not primarily treat the tendon pathology. Ultrasound-guided autologous tenocyte implantation (ATI) is a novel bioengineered treatment approach for treating tendinopathy. We report the first clinical case of ATI in a 20-year-old elite gymnast with a rotator cuff tendon injury. The patient presented with 12 months of increasing pain during gymnastics being unable to perform most skills. At 1 year after ATI the patient reported substantial improvement of clinical symptoms. Pretreatment and follow-up MRIs were reported and scored independently by two experienced musculoskeletal radiologists. Tendinopathy was improved and the partial-thickness tear healed on 3 T MRI. The patient was able to return to national-level competition.

  15. Autologous tenocyte implantation, a novel treatment for partial-thickness rotator cuff tear and tendinopathy in an elite athlete

    PubMed Central

    Wang, Allan W; Bauer, Stefan; Goonatillake, Matthew; Breidahl, William; Zheng, Ming-Hao

    2013-01-01

    Tendinopathy and small partial-thickness tears of the rotator cuff tendon are common presentations in sports medicine. No promising treatment has yet been established. Corticosteroid injections may improve symptoms in the short term but do not primarily treat the tendon pathology. Ultrasound-guided autologous tenocyte implantation (ATI) is a novel bioengineered treatment approach for treating tendinopathy. We report the first clinical case of ATI in a 20-year-old elite gymnast with a rotator cuff tendon injury. The patient presented with 12 months of increasing pain during gymnastics being unable to perform most skills. At 1 year after ATI the patient reported substantial improvement of clinical symptoms. Pretreatment and follow-up MRIs were reported and scored independently by two experienced musculoskeletal radiologists. Tendinopathy was improved and the partial-thickness tear healed on 3 T MRI. The patient was able to return to national-level competition. PMID:23314880

  16. Preparation of asiaticoside-loaded coaxially electrospinning nanofibers and their effect on deep partial-thickness burn injury.

    PubMed

    Zhu, Lifei; Liu, Xiaoyan; Du, Lina; Jin, Yiguang

    2016-10-01

    Sodium alginate and chitosan were in favor of wound healing. However, the two polymers were not compatible in one formulation due to the electrostatic interaction. Coaxially electrospinning technology could make two or more noneletrospun polymers to be electrospun in independent core and shell layer. Asiaticoside-loaded coaxially electrospinning nanofibers of alginate, polyvinyl alcohol (PVA) and chitosan (alginate/PVA/chitosan) were prepared and evaluated. Morphologies and microstructure of nanofibers were observed with scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Drug release in vitro of coaxial nanofibers was also evaluated. Deep partial-thickness burn injury were established and used to evaluate the improved healing effect of asiaticoside-loaded coaxial nanofibers. Drug-loaded coaxial nanofibers prepared with the optimized formulations and technologies had the obvious core-shell structure. Coaxial nanofibers showed faster drug release profiles in vitro and this facilitated wound healing. Its healing effect on rats with deep partial-thickness burn injury was also significant based on morphology, wound healing ratio, and pathological sections. Positive expression of vascular endothelial growth factor (VEGF), cluster of differentiation 31 (CD31), and proliferating cell nuclear antigen (PCNA), and down regulation of tumor necrosis factor (TNF) and interleukin-6 (IL-6) also validated the improved effect of wound healing. In general, the asiaticoside-loaded coaxial nanofibers had obvious core-shell structure with smooth surface and uniform diameter. Its healing effect on deep partial-thickness burn injury of rats was obvious. Asiaticoside-loaded coaxial nanofibers provide a novel promising option for treatment of deep partial-thickness burn injury.

  17. Cost-effectiveness comparison between topical silver sulfadiazine and enclosed silver dressing for partial-thickness burn treatment.

    PubMed

    Sheckter, Clifford C; Van Vliet, Michael M; Krishnan, Naveen M; Garner, Warren L

    2014-01-01

    The standard treatment of partial-thickness burns includes topical silver products such as silver sulfadiazine (SSD) cream and enclosed dressings including silver-impregnated foam (Mepilex Ag; Molnlycke Health Care, Gothenburg, Sweden) and silver-laden sheets (Aquacel Ag; ConvaTec, Skillman, NJ). The current state of health care is limited by resources, with an emphasis on evidence-based outcomes and cost-effective treatments. This study includes a decision analysis with an incremental cost-utility ratio comparing enclosed silver dressings with SSD in partial-thickness burn patients with TBSA less than 20%. A comprehensive literature review was conducted to identify clinically relevant health states in partial-thickness burn patients. These health states include successful healing, infection, and noninfected delayed healing requiring either surgery or conservative management. The probabilities of these health states were combined with Medicare CPT reimbursement codes (cost) and patient-derived utilities to fit into the decision model. Utilities were obtained using a visual analog scale during patient interviews. Expected cost and quality-adjusted life years (QALYs) were calculated using the roll-back method. The incremental cost-utility ratio for enclosed silver dressing relative to SSD was $40,167.99/QALY. One-way sensitivity analysis of complication rates confirmed robustness of the model. Assuming a maximum willingness to pay $50,000/QALY, the complication rate for SSD must be 22% or higher for enclosed silver dressing to be cost effective. By varying complication rates for SSD and enclosed silver dressings, the two-way sensitivity analysis demonstrated the cost effectiveness of using enclosed silver dressing at the majority of complication rates for both treatment modalities. Enclosed silver dressings are a cost-effective means of treating partial thickness burns.

  18. A prospective, randomized trial of silver containing hydrofiber dressing versus 1% silver sulfadiazine for the treatment of partial thickness burns.

    PubMed

    Muangman, Pornprom; Pundee, Chanin; Opasanon, Supaporn; Muangman, Saipin

    2010-08-01

    Silver sulfadiazine has been used as a topical burn wound treatment for many years. Pain associated with dressing changes is a common problem in burn wounds. Aquacel Ag, a hydrofiber dressing coated with ionic silver has been reported to reduce burn wound infection and promote antimicrobial activity. The purpose of this study was to show the benefits of Aquacel Ag for the treatment of partial thickness burns. This prospective randomized study was conducted in 70 patients who had partial thickness burns less than 15% of total body surface area and were treated at Siriraj outpatient burn clinic during December 2006-February 2008. Patients were divided into two groups: Aquacel Ag-treated group with dressing changes every 3 days (35 patients) and 1% silver sulfadiazine-treated group, with daily dressing changes (35 patients). There was no difference in demographic data including age, gender, burn percentage between groups. Time-to-wound healing pain score during dressing change and cost of treatment were compared between both groups. Time-to-wound closure was significantly shorter in the Aquacel Ag-treated group (10 +/- 3 versus 13.7 +/- 4 days, P < 0.02) as well as pain scores at days 1, 3 and 7 (4.1 +/- 2.1, 2.1 +/- 1.8, 0.9 +/- 1.4 versus 6.1 +/- 2.3, 5.2 +/- 2.1, 3.3 +/- 1.9, respectively, P < 0.02). Total cost of treatment was 52 +/- 29 US dollars for the Aquacel Ag-treated group versus 93 +/- 36 US dollars for the silver sulfadiazine-treated group. This study showed that Aquacel Ag increased time to healing, decreased pain symptoms and increased patient convenience because of limiting the frequency of replacement of the dressing at lower total cost. This study confirms the efficacy of Aquacel Ag for the treatment of partial thickness burns at an outpatient clinic.

  19. Randomized clinical study of Hydrofiber dressing with silver or silver sulfadiazine in the management of partial-thickness burns.

    PubMed

    Caruso, Daniel M; Foster, Kevin N; Blome-Eberwein, Sigri A; Twomey, John A; Herndon, David N; Luterman, Arnold; Silverstein, Paul; Antimarino, Jeffrey R; Bauer, Gregory J

    2006-01-01

    This prospective, randomized study compared protocols of care using either AQUACEL Ag Hydrofiber (ConvaTec, a Bristol-Myers Squibb company, Skillman, NJ) dressing with silver (n = 42) or silver sulfadiazine (n = 42) for up to 21 days in the management of partial-thickness burns covering 5% to 40% body surface area (BSA). AQUACEL Ag dressing was associated with less pain and anxiety during dressing changes, less burning and stinging during wear, fewer dressing changes, less nursing time, and fewer procedural medications. Silver sulfadiazine was associated with greater flexibility and ease of movement. Adverse events, including infection, were comparable between treatment groups. The AQUACEL Ag dressing protocol tended to have lower total treatment costs (Dollars 1040 vs. Dollars 1180) and a greater rate of re-epithelialization (73.8% vs 60.0%), resulting in cost-effectiveness per burn healed of Dollars 1,409.06 for AQUACEL Ag dressing and Dollars 1,967.95 for silver sulfadiazine. A protocol of care with AQUACEL(R) Ag provided clinical and economic benefits compared with silver sulfadiazine in patients with partial-thickness burns.

  20. The use of an intra-articular depth guide in the measurement of partial thickness rotator cuff tears.

    PubMed

    Carroll, Michael J; More, Kristie D; Sohmer, Stephen; Nelson, Atiba A; Sciore, Paul; Boorman, Richard; Hollinshead, Robert; Lo, Ian K Y

    2013-01-01

    Purpose. The purpose of this study was to compare the accuracy of the conventional method for determining the percentage of partial thickness rotator cuff tears to a method using an intra-articular depth guide. The clinical utility of the intra-articular depth guide was also examined. Methods. Partial rotator cuff tears were created in cadaveric shoulders. Exposed footprint, total tendon thickness, and percentage of tendon thickness torn were determined using both techniques. The results from the conventional and intra-articular depth guide methods were correlated with the true anatomic measurements. Thirty-two patients were evaluated in the clinical study. Results. Estimates of total tendon thickness (r = 0.41, P = 0.31) or percentage of thickness tears (r = 0.67, P = 0.07) using the conventional method did not correlate well with true tendon thickness. Using the intra-articular depth guide, estimates of exposed footprint (r = 0.92, P = 0.001), total tendon thickness (r = 0.96, P = 0.0001), and percentage of tendon thickness torn (r = 0.88, P = 0.004) correlated with true anatomic measurements. Seven of 32 patients had their treatment plan altered based on the measurements made by the intra-articular depth guide. Conclusions. The intra-articular depth guide appeared to better correlate with true anatomic measurements. It may be useful during the evaluation and development of treatment plans for partial thickness articular surface rotator cuff tears.

  1. Development and evaluation of silver sulfadiazine loaded microsponge based gel for partial thickness (second degree) burn wounds.

    PubMed

    Kumar, P Mahesh; Ghosh, Animesh

    2017-01-01

    Silver sulfadiazine has been frequently used as an antibacterial agent for topical treatment of partial thickness burn wounds. In this study, we present the preparation of silver sulfadiazine microsponges by w/o/w emulsion solvent evaporation method. Formulation variables were optimized by using 3(2) factorial design. The optimized microsponges were characterized by FTIR, DSC, PXRD, particle size analysis, SEM analysis and mercury intrusion porosimetry studies. Viscosity, texture analysis and ex vivo drug deposition study of optimized microsponge loaded gel were also evaluated. The safety of the optimized gel was assessed by MTT assay using epidermal keratinocyte (HaCaT) and mouse embryonic fibroblast (NIH-3T3) cell lines. In vitro antibacterial studies were carried out to compare the antibacterial inhibitory efficiency of the optimized gel against the commercial product. The efficacy of the optimized gel was evaluated by the partial thickness (second degree) burn wound model in mice. Optimized microsponge loaded gel enhanced the drug retaining capacity in the skin layers, by 3 fold higher to that of a commercial product. The antibacterial inhibitory efficiency of optimized gel was similar to the commercial product against the Staphylococcus aureus and Pseudomonas aeruginosa. Optimized gel showed reduced frequency of application, no skin irritation, low cytotoxicity on dermal cell lines and enhanced wound contraction.

  2. Macular Degeneration Partnership

    MedlinePlus

    ... Age Related Macular Degeneration) Partnership Listen AMD Month Public Service Announcement To raise awareness of AMD, the Macular Degeneration Partnership (MDP) is distributing a public service announcement (PSA) nationwide. Seen through the eyes of a ...

  3. 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.…

  4. Surgical outcomes of macular buckling techniques for macular retinoschisis in highly myopic eyes

    PubMed Central

    Mateo, Carlos; Gómez-Resa, María V.; Burés-Jelstrup, Anniken; Alkabes, Micol

    2013-01-01

    Purpose To report the anatomic and visual results following macular buckling for patients with macular retinoschisis related to high myopia. Methods Thirty-nine highly myopic eyes (mean refractive error −16.7 D; range, −9 to −24 D) of 36 patients (mean age 59 years; range, 35–79 years) presenting with macular retinoschisis associated with a posterior staphyloma, who underwent combined vitrectomy and macular buckling were evaluated. Main outcome measures included best-corrected visual acuity (BCVA) and optical coherence tomography (OCT) findings. Three cases were excluded due to short follow-up (less than 3 months). The mean follow-up was 16 months. Results The mean BCVA increased from 0.76 to 0.43 LogMAR (p = 0.001). Visual acuity improved in 30 eyes (83.3%), remained stable in three eyes (8.3%) and decreased in three eyes (8.3%). OCT showed resolution of foveoschisis with foveal reattachment in all eyes. None of the evaluated patients developed a macular hole during follow-up. Conclusion Macular buckling associated with vitrectomy results in good anatomic and visual outcomes in patients with myopic foveoschisis. PMID:24409086

  5. Application of a partial-thickness human ex vivo skin culture model in cutaneous wound healing study.

    PubMed

    Xu, Wei; Jong Hong, Seok; Jia, Shengxian; Zhao, Yanan; Galiano, Robert D; Mustoe, Thomas A

    2012-04-01

    A number of in vivo and ex vivo skin models have been applied to human wound healing studies. A reliable skin model, which recapitulates the features of human wound repair, is essential for the clinical and mechanical investigation of human cutaneous wound healing. Full-skin ex vivo culture systems have been used in wound healing studies. However, important structures of the skin, such as the differentiation of keratinocytes and epidermis-dermis junction, are poorly characterized in this model. This study aims to develop an optimized partial-thickness human ex vivo skin culture (HESC) model to maintain human skin characteristics in vitro. During our culture, the basal layer, suprabasal layer, and stratum granulosum layer of epidermis were preserved until day 8. Analyses of hemidesmosome proteins, bullous pemphigoid antigen 1 (BP180) and 2 (BP230), showed that the integrity of the basement membrane of the epidermis was well preserved in the HESC model. In contrast, an organotypic culture with human keratinocytes and fibroblasts failed to show an integrated basement membrane. Maintenance of skin structure by histological analysis and proliferation of epidermal keratinocytes by Ki67 staining were observed in our model for 12 days. Complete re-epithelialization of the wounding area was observed at day 6 post wounding when a superficial incisional wound was created. The expression of Ki-67 and keratin 6, indicators of activated keratinocytes in epidermis, was significantly upregulated and new collagen synthesis was found in the dermis during the wound healing process. As control, we also used organotypic culture in studying the differentiation of the keratinocyte layers and incisional wound repair. It turned out that our model has advantage in these study fields. The results suggest that our HESC model retains important elements of in vivo skin and has significant advantages for the wound healing studies in vitro.

  6. [Binocular vision in idiopathic macular foramen. Pre- and postoperative findings].

    PubMed

    Eckardt, U; Eckardt, C

    1995-10-01

    In recent years idiopathic macular hole has become an increasingly frequent indication for vitrectomy. To our knowledge, the literature contains no studies comparing binocular vision before and after vitrectomy. We therefore carried out a prospective study not only on visual acuity following vitrectomy but also, for the first time, on binocular vision. Stereopsis and fusion were evaluated in 37 patients with idiopathic macular holes (stage I-IV) using Bagolini striated glasses, the Titmus stereotest (contour stereopsis), the random dot test (global stereopsis), the Worth four-dot test and the phase-difference haploscope. The tests were performed preoperatively and 10-12 weeks after vitrectomy. Two patients with stage I macular hole showed no loss of stereopsis in conventional tests. One patient, however, exhibited suppression tendencies with partial exclusion. The 18 patients with stage II macular hole had a relative good visual acuity of 0.2-0.6, but subnormal binocular vision with marked suppression of foveal images. Postoperatively, the majority of these patients had symptom-free binocular vision and good stereopsis. Some, however, continued to experience foveal exclusion. Patients with macular hole stage III and IV (n = 17) had the poorest results. Although the postoperative visual acuity improved by 2 to 3 points in some patients (n = 6), in approximately one third it remained limited to global peripheral binocular vision. In summary, our findings show that even in early stages (I and II), macular hole can cause not only reduced visual acuity but also impairment or, in stage II, even loss of binocular vision. Vitrectomy in these early stages often leads to an overall improvement in visual acuity and binocular vision, whereas in more advanced stages vitrectomy often does not affect visual acuity and binocular vision. This should be taken into account when weighing up the indications for surgery.

  7. 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.

  8. Cataracts and macular degeneration.

    PubMed

    Shoch, D

    1979-09-01

    The intraocular lens restores general vision and some degree of independence and mobility to patients with dense cataracts and macular degeneration. The patient, however, must be repeatedly warned that fine central vision, particularly reading, will not be possible after the surgery. An aphakic spectacle leaves such patients a narrow band of vision when superimposed over the macular lesion, and contact lenses are too small for the patient to manage insertion without help.

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

    ClinicalTrials.gov

    2017-01-12

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

  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. Nonsilver treatment vs. silver sulfadiazine in treatment of partial-thickness burn wounds in children: a systematic review and meta-analysis.

    PubMed

    Rashaan, Zjir M; Krijnen, Pieta; Klamer, Rachel R M; Schipper, Inger B; Dekkers, Olaf M; Breederveld, Roelf S

    2014-01-01

    The evidence for application of silver-containing dressings and topicals in the treatment of partial-thickness burns in pediatric patients is largely based on clinical trials involving adult patients despite the important differences between the skin of children and adults. A systematic review and meta-analysis was performed of all randomized controlled trials comparing nonsilver treatment with silver-containing dressings and silver topical agents in children with partial-thickness burns in the acute stage. Endpoints were wound healing, grafting, infection, pain, number of dressing changes, length of hospital stay, and scarring. Seven randomized controlled trials were included involving 473 participants. All trials used silver sulfadiazine as control in comparison with five different nonsilver treatments. Most trials were of moderate quality with high risk of bias. Use of nonsilver treatment led to shorter wound healing time (weighted mean difference: -3.43 days, 95% confidence interval: -4.78, -2.07), less dressing changes (weighted mean difference: -19.89 dressing changes, 95% confidence interval: -38.12, -1.66), and shorter length of hospital stay (weighted mean difference: -2.07 days, 95% confidence interval: -2.63, -1.50) compared with silver sulfadiazine treatment, but no difference in the incidence of wound infection or grafting was found. In conclusion, nonsilver treatment may be preferred over silver sulfadiazine, but high-quality randomized controlled trials are needed to validly confirm the effectiveness of silver containing preparations, in particular silver-containing dressings, above nonsilver treatments.

  13. 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.

  14. 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.

  15. Macular telangiectasia type 2

    PubMed Central

    Issa, Peter Charbel; Gillies, Mark C.; Chew, Emily Y.; Bird, Alan C.; Heeren, Tjebo F.C.; Peto, Tunde; Holz, Frank G.; Scholl, Hendrik P.N.

    2013-01-01

    Macular telangiectasia type 2 is a bilateral disease of unknown cause with characteristic alterations of the macular capillary network and neurosensory atrophy. Its prevalence may be underestimated and has recently been shown to be as high as 0.1% in persons 40 years and older. Biomicroscopy may show reduced retinal transparency, crystalline deposits, mildly ectatic capillaries, blunted venules, retinal pigment plaques, foveal atrophy, and neovascular complexes. Fluorescein angiography shows telangiectatic capillaries predominantly temporal to the foveola in the early phase and a diffuse hyperfluorescence in the late phase. High-resolution optical coherence tomography (OCT) may reveal disruption of the photoreceptor inner segment–outer segment border, hyporeflective cavities at the level of the inner or outer retina, and atrophy of the retina in later stages. Macular telangiectasia type 2 shows a unique depletion of the macular pigment in the central retina and recent therapeutic trials showed that such depleted areas cannot re-accumulate lutein and zeaxanthin after oral supplementation. There have been various therapeutic approaches with limited or no efficacy. Recent clinical trials with compounds that block vascular endothelial growth factor (VEGF) have established the role of VEGF in the pathophysiology of the disease, but have not shown significant efficacy, at least for the nonneovascular disease stages. Recent progress in structure–function correlation may help to develop surrogate outcome measures for future clinical trials. In this review article, we summarize the current knowledge on macular telangiectasia type 2, including the epidemiology, the genetics, the clinical findings, the staging and the differential diagnosis of the disease. Findings using retinal imaging are discussed, including fluorescein angiography, OCT, adaptive optics imaging, confocal scanning laser ophthalmoscopy, and fundus autofluorescence, as are the findings using visual

  16. What Is Age-Related Macular Degeneration?

    MedlinePlus

    ... of Low Vision Age-Related Macular Degeneration Vision Simulator AMD Pictures and Videos: What Does Macular Degeneration ... degeneration as part of the body's natural aging process. There are different kinds of macular problems, but ...

  17. Genetics Home Reference: Stargardt macular degeneration

    MedlinePlus

    ... Genetics Home Health Conditions Stargardt macular degeneration Stargardt macular degeneration Enable Javascript to view the expand/collapse boxes. Download PDF Open All Close All Description Stargardt macular degeneration is a genetic eye disorder that causes progressive ...

  18. The use of de-differentiated chondrocytes delivered by a heparin-based hydrogel to regenerate cartilage in partial-thickness defects.

    PubMed

    Kim, Mihye; Kim, Se Eun; Kang, Seong Soo; Kim, Young Ha; Tae, Giyoong

    2011-11-01

    Partial-thickness cartilage defects, with no subchondral bone injury, do not repair spontaneously, thus there is no clinically effective treatment for these lesions. Although the autologous chondrocyte transplantation (ACT) is one of the promising approaches for cartilage repair, it requires in vitro cell expansion to get sufficient cells, but chondrocytes lose their chondrogenic phenotype during expansion by monolayer culture, leading to de-differentiation. In this study, a heparin-based hydrogel was evaluated and optimized to induce cartilage regeneration with de-differentiated chondrocytes. First, re-differentiation of de-differentiated chondrocytes encapsulated in heparin-based hydrogels was characterized in vitro with various polymer concentrations (from 3 to 20 wt.%). Even under a normal cell culture condition (no growth factors or chondrogenic components), efficient re-differentiation of cells was observed with the optimum at 10 wt.% hydrogel, showing the complete re-differentiation within a week. Efficient re-differentiation and cartilage formation of de-differentiated cell/hydrogel construct were also confirmed in vivo by subcutaneous implantation on the back of nude mice. Finally, excellent cartilage regeneration and good integration with surrounding, similar to natural cartilage, was also observed by delivering de-differentiated chondrocytes using the heparin-based hydrogel in partial-thickness defects of rabbit knees whereas no healing was observed for the control defects. These results demonstrate that the heparin-based hydrogel is very efficient for re-differentiation of expanded chondrocytes and cartilage regeneration without using any exogenous inducing factors, thus it could serve as an injectable cell-carrier and scaffold for cartilage repair. Excellent chondrogenic nature of the heparin-based hydrogel might be associated with the hydrogel characteristic that can secure endogenous growth factors secreted from chondrocytes, which then can promote

  19. Macular Surgery Using Intraoperative Spectral Domain Optical Coherence Tomography

    PubMed Central

    Riazi-Esfahani, Mohammad; Khademi, Mohammad Reza; Mazloumi, Mehdi; Khodabandeh, Alireza; Riazi-Esfahani, Hamid

    2015-01-01

    Purpose: To report the use of intraoperative spectral domain optical coherence tomography (SD-OCT) for detecting anatomical changes during macular surgery. Methods: In a consecutive case series, 32 eyes of 32 patients undergoing concurrent pars plana vitrectomy and intraoperative SD-OCT for macular hole (MH), epiretinal membrane (ERM) and vitreomacular traction (VMT) were enrolled. Intraoperative changes in retinal thickness and dimensions of the macular hole were measured in patients with ERM and VMT following surgical manipulation using a hand-held SD-OCT device (iVue, Optovue Inc., Fremont, CA, USA). Results: SD-OCT images of sixteen eyes with macular hole were subjected to quantitative and qualitative analysis. All MH dimensions remained stable during consecutive stages of surgery except for MH apex diameter, which showed a significant decrease after internal limiting membrane (ILM) peeling (P=0.025). Quantitative analysis of ten patients with ERM showed a significant decrease in retinal thickness after membrane removal (P=0.018) which did not remain significant until the end of the procedure (P=0.8). In three cases, subretinal fluid was formed after ILM peeling. Quantitative analysis of five patients with VMT showed a decrease in retinal thickness during consecutive steps of the surgery, although these changes were not significant. In two cases, subretinal fluid was formed after ILM peeling. Conclusion: Intraoperative SD-OCT is a useful imaging technique which provides vitreoretinal surgeons with rapid awareness of changes in macular anatomy during surgery and may therefore result in better anatomical and visual outcomes. PMID:26730318

  20. [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].

  1. Effect of glenohumeral abduction angle on the mechanical interaction between the supraspinatus and infraspinatus tendons for the intact, partial-thickness torn, and repaired supraspinatus tendon conditions.

    PubMed

    Andarawis-Puri, Nelly; Kuntz, Andrew F; Ramsey, Matthew L; Soslowsky, Louis J

    2010-07-01

    Rotator cuff tears are difficult to manage because of the structural and mechanical inhomogeneity of the supraspinatus tendon. Previously, we showed that with the arm at the side, the supraspinatus and infraspinatus tendons mechanically interact such that conditions that increase supraspinatus tendon strain, such as load or full-thickness tears, also increase infraspinatus tendon strain. This suggests that the infraspinatus tendon may shield the supraspinatus tendon from further injury while becoming at increased risk of injury itself. In this study, the effect of glenohumeral abduction angle on the interaction between the two tendons was evaluated for supraspinatus tendon partial-thickness tears and two repair techniques. Principal strains were quantified in both tendons for 0 degrees , 30 degrees , and 60 degrees of glenohumeral abduction. Results showed that interaction between the two tendons is interrupted by an increase in abduction angle for all supraspinatus tendon conditions evaluated. Infraspinatus tendon strain was lower at 30 degrees and 60 degrees than at 0 degrees abduction angle. In conclusion, interaction between the supraspinatus and infraspinatus tendons is interrupted with increase in abduction angle. Additionally, 30 degrees abduction should be further evaluated for management of rotator cuff tears and repairs as it is the angle at which both supraspinatus and infraspinatus tendon strain is decreased.

  2. Effect of chitosan-gluconic acid conjugate/poly(vinyl alcohol) cryogels as wound dressing on partial-thickness wounds in diabetic rats.

    PubMed

    Takei, Takayuki; Nakahara, Hideki; Tanaka, Sadao; Nishimata, Hiroto; Yoshida, Masahiro; Kawakami, Koei

    2013-10-01

    We previously developed chitosan cryogels from chitosan-gluconic acid conjugate without using toxic additives for wound care. In this study, we improved physiological characteristics of the previous cryogels by incorporating poly(vinyl alcohol) that also form cryogels. Mechanical strength of the cryogels was more than two times higher than that of the previous cryogels. Furthermore, the incorporation of poly(vinyl alcohol) enhanced water retention and resistance to degradation of the gels by lysozyme. The cryogels retained the favorable biological properties of the previous cryogels that they accelerate infiltration of inflammatory cells into wound sites. Time period for repairing 50 % of initial area of partial-thickness skin wound treated with the cryogels (4.0 ± 1.1 days) was shorter than those with gauze (6.5 ± 0.3 days) or a commercial hydrogel dressing (5.7 ± 0.3 days). Finally, we confirmed that incorporation of basic fibroblast growth factor into the cryogels was effective to further accelerate wound healing (2.7 ± 1.0 days). These results demonstrate that the cryogels in this study are promising for wound care.

  3. Achondroplasia and Macular Coloboma.

    PubMed

    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.

  4. Comparative effectiveness of different wound dressings for patients with partial-thickness burns: study protocol of a systematic review and a Bayesian framework network meta-analysis

    PubMed Central

    Jiang, Qiong; Chen, Zhao-Hong; Wang, Shun-Bin; Chen, Xiao-Dong

    2017-01-01

    Introduction Selecting a suitable wound dressing for patients with partial-thickness burns (PTBs) is important in wound care. However, the comparative effectiveness of different dressings has not been studied. We report the protocol of a network meta-analysis designed to combine direct and indirect evidence of wound dressings in the management of PTB. Methods and analysis We will search for randomised controlled trials (RCTs) evaluating the wound-healing effect of a wound dressing in the management of PTB. Searches will be conducted in MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, the Cochrane Wounds Group Specialised Register and CINAHL. A comprehensive search strategy is developed to retrieve articles reporting potentially eligible RCTs. Besides, we will contact the experts in the field and review the conference proceedings to locate non-published studies. The reference lists of articles will be reviewed for any candidate studies. Two independent reviewers will screen titles and abstracts of the candidate articles. All eligible RCTs will be obtained in full text to perform a review. Disagreement on eligibility of an RCT will be solved by group discussion. The information of participants, interventions, comparisons and outcomes from included RCTs will be recorded and summarised. The primary outcome is time to complete wound healing. Secondary outcomes include the proportion of burns completely healed at the end of treatment, change in wound surface area at the end of treatment, incidence of adverse events, etc. Ethics and dissemination The result of this review will provide evidence for the comparative effectiveness of different wound dressings in the management of PTB. It will also facilitate decision-making in choosing a suitable wound dressing. We will disseminate the review through a peer-review journal and conference abstracts or posters. Trial registration number PROSPERO CRD42016041574; Pre-results. PMID:28336737

  5. Age-Related Macular Degeneration

    MedlinePlus

    ... version of this page please turn Javascript on. Age-related Macular Degeneration About AMD Click for more ... a leading cause of vision loss among people age 60 and older. It causes damage to the ...

  6. Idiopathic horseshoe-like macular tear: a case report

    PubMed Central

    Kubota, Masaomi; Shibata, Tomohiro; Gunji, Hisato; Tsuneoka, Hiroshi

    2016-01-01

    Background Although a few cases with idiopathic horseshoe-like macular tear have been reported, the mechanism remains unknown and a standard treatment has yet to be determined. Objective To report the outcome for a patient with idiopathic horseshoe-like macular tear who underwent vitreous surgery. Case report A 65-year-old man with no previous injury or ophthalmic disease presented with abnormal vision in his left eye. Best-corrected visual acuity was 0.8 in the right and 0.3 in the left, and the relative afferent pupillary defect was negative. Ophthalmoscopy revealed a horseshoe-like tear on the temporal side of the macula in the left eye. The tear size was 0.75 disc diameters (DD). Optical coherence tomography showed that the focal retinal detachment reached the fovea. A few days after the first visit, there was no longer adhesion of the flap of the tear to the retina and the tear size had increased to 1.5 DD. The patient underwent vitreous surgery similar to large macular hole surgery, with the tear closure repaired using the inverted internal limiting membrane flap technique with 20% SF6 gas tamponade. Although the tear decreased to 0.5 DD after the surgery, complete closure of the tear was not achieved. Conclusion While cases with horseshoe-like macular tear following trauma and branch retinal vein occlusion have been reported, to the best of our knowledge, this is the first reported idiopathic case. In the present case, there was expansion of the tear until the patient actually underwent surgery. If vertical vitreous traction indeed plays a role in horseshoe-like macular tears, this will need to be taken into consideration at the time of the vitreous surgery in these types of cases. PMID:27555798

  7. Age-related macular degeneration.

    PubMed

    Lim, Laurence S; Mitchell, Paul; Seddon, Johanna M; Holz, Frank G; Wong, Tien Y

    2012-05-05

    Age-related macular degeneration is a major cause of blindness worldwide. With ageing populations in many countries, more than 20% might have the disorder. Advanced age-related macular degeneration, including neovascular age-related macular degeneration (wet) and geographic atrophy (late dry), is associated with substantial, progressive visual impairment. Major risk factors include cigarette smoking, nutritional factors, cardiovascular diseases, and genetic markers, including genes regulating complement, lipid, angiogenic, and extracellular matrix pathways. Some studies have suggested a declining prevalence of age-related macular degeneration, perhaps due to reduced exposure to modifiable risk factors. Accurate diagnosis combines clinical examination and investigations, including retinal photography, angiography, and optical coherence tomography. Dietary anti-oxidant supplementation slows progression of the disease. Treatment for neovascular age-related macular degeneration incorporates intraocular injections of anti-VEGF agents, occasionally combined with other modalities. Evidence suggests that two commonly used anti-VEGF therapies, ranibizumab and bevacizumab, have similar efficacy, but possible differences in systemic safety are difficult to assess. Future treatments include inhibition of other angiogenic factors, and regenerative and topical therapies.

  8. [Age related macular degeneration].

    PubMed

    Sayen, Alexandra; Hubert, Isabelle; Berrod, Jean-Paul

    2011-02-01

    Age-related macular degeneration (ARMD) is a multifactorial disease caused by a combination of genetic and environmental factors. It is the first cause of blindness in patients over 50 in the western world. The disease has been traditionally classified into early and late stages with dry (atrophic) and wet (neovascular) forms: neovascular form is characterized by new blood vessels development under the macula (choroidal neovascularisation) which lead to a rapid decline of vision associated with metamorphopsia and requiring an urgent ophtalmological examination. Optical coherence tomography is now one of the most important part of the examination for diagnosis and treatment. Patient with age related maculopathy should consider taking a dietary supplement such that used in AREDS. The treatment of the wet ARMD has largely beneficied since year 2006 of anti-VEGF (vascular endothelial growth factor) molecules such as ranibizumab or bevacizumab given as repeated intravitreal injections. A systematic follow up each 4 to 8 week in required for several years. There is no effective treatment at the moment for dry AMD. For patients with binocular visual acuity under 60/200 rehabilitation includes low vision specialist, vision aids and psychological support.

  9. Automated macular pathology diagnosis in retinal OCT images using multi-scale spatial pyramid and local binary patterns in texture and shape encoding.

    PubMed

    Liu, Yu-Ying; Chen, Mei; Ishikawa, Hiroshi; Wollstein, Gadi; Schuman, Joel S; Rehg, James M

    2011-10-01

    We address a novel problem domain in the analysis of optical coherence tomography (OCT) images: the diagnosis of multiple macular pathologies in retinal OCT images. The goal is to identify the presence of normal macula and each of three types of macular pathologies, namely, macular edema, macular hole, and age-related macular degeneration, in the OCT slice centered at the fovea. We use a machine learning approach based on global image descriptors formed from a multi-scale spatial pyramid. Our local features are dimension-reduced local binary pattern histograms, which are capable of encoding texture and shape information in retinal OCT images and their edge maps, respectively. Our representation operates at multiple spatial scales and granularities, leading to robust performance. We use 2-class support vector machine classifiers to identify the presence of normal macula and each of the three pathologies. To further discriminate sub-types within a pathology, we also build a classifier to differentiate full-thickness holes from pseudo-holes within the macular hole category. We conduct extensive experiments on a large dataset of 326 OCT scans from 136 subjects. The results show that the proposed method is very effective (all AUC>0.93).

  10. Diabetic macular edema.

    PubMed

    Stefánsson, Einar

    2009-07-01

    A variety of treatment options are available for the treatment of diabetic macular edema. They include laser photocoagulation, anti-VEGF drugs, intravitreal steroids, and vitrectomy with or without release of vitreoretinal traction. A full understanding of the physiological mechanisms of these treatment modalities allows sensible combination of treatment options. Retinal photocoagulation has repeatedly been shown to improve retinal oxygenation, as does vitrectomy. Oxygen naturally reduces VEGF production and thereby decreases leakage of plasma proteins from capillaries into the tissue. In addition, vitrectomy allows faster clearance of cytokines, such as VEGF, from the retina into the vitreous cavity. The VEGF-lowering effect of photocoagulation and vitrectomy can be augmented with anti-VEGF drugs and corticosteroids reduce the effect of VEGF on capillary permeability. Starling's law explains vasogenic edema, which is controlled by osmotic and hydrostatic gradients between vessel and tissue. It explains how VEGF-induced vascular permeability causes plasma protein to leak into the tissue interstitial space, thus decreasing the osmotic pressure gradient between vessel and tissue, resulting in water accumulation, i.e. edema. This is reversed by reducing VEGF production, which is achieved with laser treatment; or by removing VEGF with antibodies or vitrectomy; or by reducing the permeability effect with steroids. At the same time, Starling's law takes into account hemodynamic changes that affect the hydrostatic gradient. High arterial blood pressure and hypoxic vasodilatation increase the hydrostatic pressure in the microcirculation, which increases water flux from vessel to tissue and induce edema. Treatment of arterial hypertension or reversal of retinal hypoxia with laser reverses this pathophysiology and reduces edema. Newton's third law explains, that vitreoretinal traction decreases hydrostatic tissue pressure in the retina, increases the pressure gradient

  11. 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.

  12. Uveitic Macular Edema: Treatment Update

    PubMed Central

    Goldhardt, Raquel; Rosen, Bradley Simon

    2016-01-01

    The aim of this review is to summarize recent developments in the treatment of uveitic macular edema (ME). ME represent a major cause of visual loss in uveitis and adequate management is crucial for the maintenance of useful vision in patients with chronic uveitis. PMID:27347446

  13. 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.

  14. Macular thickness and macular volume measurements using spectral domain optical coherence tomography in normal Nepalese eyes

    PubMed Central

    Pokharel, Amrit; Shrestha, Gauri Shankar; Shrestha, Jyoti Baba

    2016-01-01

    Purpose To record the normative values for macular thickness and macular volume in normal Nepalese eyes. Methods In all, 126 eyes of 63 emmetropic subjects (mean age: 21.17±6.76 years; range: 10–37 years) were assessed for macular thickness and macular volume, using spectral domain-optical coherence tomography over 6×6 mm2 in the posterior pole. A fast macular thickness protocol was employed. Statistics such as the mean, median, standard deviation, percentiles, and range were used, while a P-value was set at 0.05 to test significance. Results Average macular thickness and total macular volume were larger in males compared to females. With each year of increasing age, these variables decreased by 0.556 μm and 0.0156 mm3 for average macular thickness and total macular volume, respectively. The macular thickness was greatest in the inner superior section and lowest at the center of the fovea. The volume was greatest in the outer nasal section and thinnest in the fovea. The central subfield thickness (r=−0.243, P=0.055) and foveal volume (r=0.216, P=0.09) did not correlate with age. Conclusion Males and females differ significantly with regard to macular thickness and macular volume measurements. Reports by other studies that the increase in axial length reduced thickness and volume, were negated by this study which found a positive correlation among axial length, thickness, and volume. PMID:27041990

  15. [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.

  16. [Pathogenesis of age-related macular degeneration].

    PubMed

    Kaarniranta, Kai; Seitsonen, Sanna; Paimela, Tuomas; Meri, Seppo; Immonen, Ilkka

    2009-01-01

    Age-related macular degeneration is a multiform disease of the macula, the region responsible for detailed central vision. In recent years, plenty of new knowledge of the pathogenesis of this disease has been obtained, and the treatment of exudative macular degeneration has greatly progressed. The number of patients with age-related macular degeneration will multiply in the following decades, because knowledge of mechanisms of development of macular degeneration that could be subject to therapeutic measures is insufficient. Central underlying factors are genetic inheritance, exposure of the retina to chronic oxidative stress and accumulation of inflammation-inducing harmful proteins into or outside of retinal cells.

  17. The genetics of inherited macular dystrophies

    PubMed Central

    Michaelides, M; Hunt, D; Moore, A

    2003-01-01

    The aim of this paper is to review current knowledge relating to the monogenic macular dystrophies, with discussion of currently mapped genes, chromosomal loci and genotype-phenotype relationships. Inherited systemic disorders with a macular dystrophy component will not be discussed. PMID:12960208

  18. 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.

  19. [Age-related macular degeneration].

    PubMed

    Budzinskaia, M V

    2014-01-01

    The review provides an update on the pathogenesis and new treatment modalities for neovascular age-related macular degeneration (AMD). The impact of polymorphism in particular genes, including complement factor H (CFH), age-related maculopathy susceptibility 2 (ARMS2/LOC387715), and serine peptidase (HTRA1), on AMD development is discussed. Clinical presentations of different forms of exudative AMD, that is classic, occult, or more often mixed choroidal neovascularization, retinal angiomatous proliferation, and choroidal polypoidal vasculopathy, are described. Particular attention is paid to the results of recent clinical trials and safety issues around the therapy.

  20. Age-related macular degeneration

    PubMed Central

    Querques, Giuseppe; Avellis, Fernando Onofrio; Querques, Lea; Bandello, Francesco; Souied, Eric H

    2011-01-01

    Clinical question: Is there any new knowledge about the pathogenesis and treatment of age-related macular degeneration (AMD)? Results: We now understand better the biochemical and pathological pathways involved in the genesis of AMD. Treatment of exudative AMD is based on intravitreal injection of new antivascular endothelial growth factor drugs for which there does not yet exist a unique recognized strategy of administration. No therapies are actually available for atrophic AMD, despite some experimental new pharmacological approaches. Implementation: strategy of administration, safety of intravitreal injection PMID:21654887

  1. 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

  2. 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

  3. Black holes.

    PubMed

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

    2001-09-11

    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.

  4. Value of optical coherence tomography in the detection of macular pathology before the removal of silicone oil

    PubMed Central

    Rashad, Mohammad Ahmad; Mohamed, Ahmed Abdel Aliem; Ahmed, Asmaa Ismail

    2016-01-01

    Purpose To assess the pathological macular changes with optical coherence tomography (OCT) before the removal of silicone oil (SiO) in eyes that had undergone pars plana vitrectomy for complicated forms of retinal detachment (RD). Patients and methods Subjects included 48 patients (51 eyes) with complicated RD including proliferative vitreoretinopathy, proliferative diabetic retinopathy, recurrent RD, penetrating trauma, uveitis, giant retinal tears, and macular holes. All the eyes had undergone SiO injection. Furthermore, all eyes had been planned for the removal of SiO 6–12 months after the primary surgery. Finally, all eyes had a fundus examination and OCT examination before the silicone oil removal. Results OCT findings indicated epiretinal membrane in 41% of the eyes, macular edema in 17%, macular detachment in 13.5%, macular thinning in 13.5%, macular holes in 10%, and subretinal membranes in 2%. Preoperative OCT was normal in only 12% of the eyes, while a clinical fundus examination was normal in 43% (P<0.001). Eyes with normal OCT had significantly better mean logMAR (0.35) than eyes with pathological changes detected through OCT (1.28; P<0.001). Surgical modifications were made during the removal of SiO in 74.5% of the eyes. Conclusion OCT detected significantly more pathological changes than a clinical fundus examination. This had an impact on both surgical step modification during the removal of SiO and predictability of visual outcome after the removal of SiO. PMID:26855558

  5. [Macular coloboma type Leber's congenital amaurosis].

    PubMed

    Kiratli, H; Bozkurt, B

    2002-01-01

    Three brothers, with the macular coloboma type Leber's congenital amaurosis aged 10, 8, and 6 years respectively, are described in this report. Only the two elder brothers were symptomatic while the third patient had no complaint at the time of diagnosis. The patients had no associated systemic or ocular disorders, including nystagmus. They had mild myopic astigmatism. All three had a relatively well-circumscribed bilateral macular atrophy with a seemingly normal peripheral retina. The electroretinogram was non recordable but the visualy evoked potential responses were within normal limits. During three years of follow-up, the macular lesions did not progress and the visual acuity did not deteriorate further. Our experience with these three familial cases supports the general view that the macular coloboma variant does not necessarily have the typical signs and symptoms and perhaps also the dismal prognosis of classic Leber's congenital amaurosis, and as such should stand as a distinct subtype of the disease.

  6. 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 ...

  7. Flicker fusion thresholds in Best macular dystrophy.

    PubMed

    Massof, R W; Fleischman, J A; Fine, S L; Yoder, F

    1977-06-01

    Flicker fusion threshold intensities were measured as a function of flicker frequency for patients with Best macular dystrophy having normal or near-normal Snellen visual acuity. These data were found to differ from normal in ways that may be interpreted to be an abnormal elevation of the foveal cone threshold, a loss of cone temporal resolution, or both. The results led to the conclusion that Best macular dystrophy affects the neurosensory retina even when Snellen visual acuity is normal.

  8. Automated macular pathology diagnosis in retinal OCT images using multi-scale spatial pyramid with local binary patterns.

    PubMed

    Liu, Yu-Ying; Chen, Mei; Ishikawa, Hiroshi; Wollstein, Gadi; Schuman, Joel S; Rehg, James M

    2010-01-01

    We address a novel problem domain in the analysis of optical coherence tomography (OCT) images: the diagnosis of multiple macular pathologies in retinal OCT images. The goal is to identify the presence of normal macula and each of three types of macular pathologies, namely, macular hole, macular edema, and age-related macular degeneration, in the OCT slice centered at the fovea. We use a machine learning approach based on global image descriptors formed from a multi-scale spatial pyramid. Our local descriptors are dimension-reduced Local Binary Pattern histograms, which are capable of encoding texture information from OCT images of the retina. Our representation operates at multiple spatial scales and granularities, leading to robust performance. We use 2-class Support Vector Machine classifiers to identify the presence of normal macula and each of the three pathologies. We conducted extensive experiments on a large dataset consisting of 326 OCT scans from 136 patients. The results show that the proposed method is very effective.

  9. Overview of diabetic macular edema.

    PubMed

    Holekamp, Nancy M

    2016-07-01

    Diabetes mellitus (DM) is a rapidly growing epidemic in the United States, and it is expected to affect 592 million individuals within the next 20 years. Diabetic retinopathy (DR) and diabetic macular edema (DME) are the 2 most common ophthalmic complications of DM. DR is the leading cause of blindness among working-age adults around the world, and development of DR is tied to DM disease duration. With the only identifier of early markers of DR being a complete ophthalmic exam, early signs of the disease are asymptomatic. Yearly, or at least every other year, ophthalmic exams are recommended for all patients with DM; but often, individuals with DM have not undergone screening exams and do not have regular eye exams until vision loss has occurred. With spending estimates of $490 million to treat the vision complications of DM, it is clear that DR and DME impose a substantial burden for patients, caregivers, and healthcare systems.

  10. Macular edema: definition and basic concepts.

    PubMed

    Coscas, Gabriel; Cunha-Vaz, José; Soubrane, Gisèle

    2010-01-01

    Macular edema is the result of an accumulation of fluid in the retinal layers around the fovea. It contributes to vision loss by altering the functional cell relationship in the retina and promoting an inflammatory reparative response. Macular edema may be intracellular or extracellular. Intracellular accumulation of fluid, also called cytotoxic edema, is an alteration of the cellular ionic distribution. Extracellular accumulation of fluid, which is more frequent and clinically more relevant, is directly associated with an alteration of the blood-retinal barrier (BRB). The following parameters are relevant for clinical evaluation of macular edema: extent of the macular edema (i.e., the area that shows increased retinal thickness); distribution of the edema in the macular area (i.e., focal versus diffuse macular edema); central foveal involvement (central area 500 microm); fluorescein leakage (evidence of alteration of the BRB or 'open barrier') and intraretinal cysts; signs of ischemia (broken perifoveolar capillary arcade and/or areas of capillary closure); presence or absence of vitreous traction; increase in retinal thickness and cysts in the retina (inner or outer), and chronicity of the edema (i.e., time elapsed since initial diagnosis and response to therapy). It is essential to establish associations and correlations of all the different images obtained, regardless of whether the same or different modalities are used.

  11. Macular pigment and lutein supplementation in choroideremia.

    PubMed

    Duncan, Jacque L; Aleman, Tomas S; Gardner, Leigh M; De Castro, Elaine; Marks, Daniel A; Emmons, Jessica M; Bieber, Michelle L; Steinberg, Janet D; Bennett, Jean; Stone, Edwin M; MacDonald, Ian M; Cideciyan, Artur V; Maguire, Maureen G; Jacobson, Samuel G

    2002-03-01

    Choroideremia is an incurable X-linked retinal degeneration caused by mutations in the gene encoding Rab escort protein-1. A group of clinically defined and genotyped patients were studied to determine: (1) the degree of rod and cone dysfunction and structural abnormality in the central retina and the level of macular pigment; and (2) the response of macular pigment and foveal vision to a 6 month trial of supplementation with oral lutein (at 20 mg per day). Rod and cone-mediated function was measured with dark-adapted static perimetry; in vivo retinal structure was determined with optical coherence tomography; and macular pigment optical density was measured with heterochromatic flicker photometry. In this cohort of patients (ages 15-65 years), both rod- and cone-mediated central function declined with age as did central retinal thickness. Macular pigment levels did not differ between patients and male control subjects. Supplementation of oral lutein in a subset of patients led to an increase in serum lutein and macular pigment levels; absolute foveal sensitivity did not change. It is concluded that macular pigment density can be augmented by oral intake of lutein in patients with choroideremia. There was no short-term change in the central vision of the patients on the supplement, but long-term influences of lutein supplementation on disease natural history warrant further study.

  12. Management of macular epiretinal membrane by vitrectomy and intravitreal triamcinolone.

    PubMed

    Shukla, Dhananjay

    2014-04-01

    A patient underwent successful vitrectomy for macular epiretinal membrane with anatomical and functional improvement. 10 weeks later, there was a recurrence of macular edema with corresponding visual decline. An intravitreal injection of triamcinolone acetonide not only restored the macular anatomy but also improved the visual outcome beyond that achieved after surgery.

  13. Treatment for Macular Telangiectasia Type 2.

    PubMed

    Charbel Issa, Peter; Kupitz, Elke H; Heeren, Tjebo F C; Holz, Frank G

    2016-01-01

    Macular telangiectasia (MacTel) type 2 is a bilateral disease of unknown cause with localized retinal degeneration and characteristic changes of the retinal vasculature. Funduscopic findings include reduced retinal transparency, crystalline deposits, ectatic capillaries, blunted venules, retinal pigment plaques, foveal atrophy and neovascular complexes. Leakage of telangiectatic macular capillaries is a characteristic finding on fluorescein angiography, and neurosensory atrophy may be present on optical coherence tomography images. Furthermore, there is a specific depletion of macular pigment in the central retina. Depending on the development of neovascular membranes, a nonproliferative and a proliferative (neovascular) disease stage may be distinguished. To date, there is no evidence for an effective treatment of nonproliferative MacTel type 2. Patients with proliferative MacTel type 2 and hence decreasing visual function may benefit from intravitreal application of vascular endothelial growth factor inhibitors. Early treatment and a small size of the neovascular membrane might be predictive factors for visual function outcome.

  14. [Epidemiology and development of macular edema in the diabetic].

    PubMed

    Zghal-Mokni, I; Jeddi, A; Boujemaa, C; Ben Hadj Alouane, W; Gaigi, S; Ayed, S

    2001-12-01

    Macular edema is the first cause of blindness in diabetics. Macular edema is defined by macular thickening or deposits of hard exudates. On 1000 diabetics examined over 2 years, 60 patients had a macular edema of which we retained 38 cases(54 eyes). All the patients had an ophthalmologic examination with a retinal angiography. Laser photocoagulation with green Argon laser was instituted in 50 eyes. 63% had background rethinopathy. Total or partial regression of the edema happened in 84.4%. Laser photocoagulation decrease by the half vision loss risk. Interest of early detection and treatment to decrease blindness incidence of macular edema in diabetics.

  15. 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.

  16. [New aspects in age related macular degeneration].

    PubMed

    Turlea, C

    2012-01-01

    Being the leading cause of blindness in modern world Age Related Macular Degeneration has beneficiated in the last decade of important progress in diagnosis, classification and the discovery of diverse factors who contribute to the etiology of this disease. Treatments have arised who can postpone the irreversible evolution of the disease and thus preserve vision. Recent findings have identified predisposing genetic factors and also inflamatory and imunological parameters that can be modified trough a good and adequate prevention and therapy This articole reviews new aspects of patology of Age Related Macular Degeneration like the role of complement in maintaining inflamation and the role of oxidative stress on different structures of the retina.

  17. Age-related macular degeneration.

    PubMed

    Cheung, Lily K; Eaton, Angie

    2013-08-01

    Age-related macular degeneration (AMD) is the leading cause of blindness in the elderly, and the prevalence of the disease increases exponentially with every decade after age 50 years. It is a multifactorial disease involving a complex interplay of genetic, environmental, metabolic, and functional factors. Besides smoking, hypertension, obesity, and certain dietary habits, a growing body of evidence indicates that inflammation and the immune system may play a key role in the development of the disease. AMD may progress from the early form to the intermediate form and then to the advanced form, where two subtypes exist: the nonneovascular (dry) type and the neovascular (wet) type. The results from the Age-Related Eye Disease Study have shown that for the nonneovascular type of AMD, supplementation with high-dose antioxidants (vitamin C, vitamin E, and β-carotene) and zinc is recommended for those with the intermediate form of AMD in one or both eyes or with advanced AMD or vision loss due to AMD in one eye. As for the neovascular type of the advanced AMD, the current standard of therapy is intravitreal injections of vascular endothelial growth factor inhibitors. In addition, lifestyle and dietary modifications including improved physical activity, reduced daily sodium intake, and reduced intake of solid fats, added sugars, cholesterol, and refined grain foods are recommended. To date, no study has demonstrated that AMD can be cured or effectively prevented. Clearly, more research is needed to fully understand the pathophysiology as well as to develop prevention and treatment strategies for this devastating disease.

  18. Quantification of photoreceptor layer thickness in different macular pathologies using ultrahigh-resolution optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Drexler, Wolfgang; Hermann, Boris; Unterhuber, Angelika; Sattmann, Harald; Wirtitsch, Matthias; Stur, Michael; Scholda, Christoph; Ergun, Erdem; Anger, Elisabeth; Ko, Tony H.; Schubert, Christian; Ahnelt, Peter K.; Fujimoto, James G.; Fercher, Adolf F.

    2004-07-01

    In vivo ultrahigh resolution ophthalmic OCT has been performed in more than 300 eyes of 200 patients with several retinal pathologies, demonstrating unprecedented visualization of all major intraretinal layers, in particular the photoreceptor layer. Visualization as well as quantification of the inner and outer segment of the photoreceptor layer especially in the foveal region has been acvhieved. In normal subjects the photoreceptor layer thickness in the center of the fovea is about of 90 μm, approximately equally distributed to the inner and the outer photoreceptor segment. In the parafoveal region this thickness is reduced to ~50 μm (~30 μm for the inner and ~20 μm for the outer segment). This is in good agreement with well known increase of cone outer segments in the central foveal region. Photoreceptor layer impairment in different macular pathologies like macular hole, central serous chorioretinopathy, age related macular degeneration, foveomacular dystrophies, Stargardt dystrophy as well as retinitis pigmentosa has been investigated. Photoreceptor layer loss significantly correlated with visual acuity (R2 = 0.6, p < 0.001) and microperimetry findings for the first time in 22 eyes with Stargardt dystrophy. Visualization and quantification of photoreceptor inner and outer segment using ultrahigh resolution OCT has the potential to improve early ophthalmic diagnosis, contributes to a better understanding of pathogenesis of retinal diseases as well as might have impact in the development and monitoring of novel therapy approaches.

  19. 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

  20. 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,…

  1. Macular colobomas in Leber's congenital amaurosis.

    PubMed

    Margolis, S; Scher, B M; Carr, R E

    1977-01-01

    Two siblings with Leber's congenital amaurosis had the unusual association of bilateral macular colobomas. In addition to the colobomas, the patients also had deafmutism, severe myopia, large corneas, and an unusual discrete area of peripapillary tapetoretinal sheen. Electrodiagnostic evaluation of patients with congenitally poor visual ascuity and a central retinal defect differentiated a localized loss of funciton from a degeneration involving the entire retina.

  2. Bilateral macular colobomas in Leber's congenital amaurosis.

    PubMed

    Murayama, K; Adachi-Usami, E

    1989-06-01

    Two siblings with Leber's congenital amaurosis had bilateral macular colobomas, nystagmus, extinguished ERGs, and degenerative salt and pepper like changes in the fundus. They had non-recordable or non-meaningful visually evoked cortical potentials in response to both flash and pattern stimuli. The ophthalmic conditions were thought to be inherited as an autosomal recessive trait.

  3. 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…

  4. 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

  5. INTRAVITREAL CORTICOSTEROIDS IN DIABETIC MACULAR EDEMA

    PubMed Central

    Bailey, Clare; Loewenstein, Anat; Massin, Pascale

    2015-01-01

    Purpose: To review the relationship between kinetics, efficacy, and safety of several corticosteroid formulations for the treatment of diabetic macular edema. Methods: Reports of corticosteroid use for the treatment of diabetic macular edema were identified by a literature search, which focused on the pharmacokinetics, efficacy, and safety of these agents in preclinical animal models and clinical trials. Results: Available corticosteroids for diabetic macular edema treatment include intravitreal triamcinolone acetonide, dexamethasone, and fluocinolone acetonide. Because of differences in solubility and bioavailability, various delivery mechanisms are used. Bioerodible delivery systems achieve higher maximum concentrations than nonbioerodible formulations. There is a relationship between visual gains and drug persistence in the intravitreal compartment. Safety effects were more complex; level of intravitreal triamcinolone acetonide exposure is related to development of elevated intraocular pressure and cataract; this does not seem to be the case for dexamethasone, where two different doses showed similar mean intraocular pressure and incidence of cataract surgery. With fluocinolone acetonide, rates of intraocular pressure elevations requiring surgery seem to be dose related; rates of cataract extraction were similar regardless of dose. Conclusion: Available corticosteroids for diabetic macular edema exhibit different pharmacokinetic profiles that impact efficacy and adverse events and should be taken into account when developing individualized treatment plans. PMID:26352555

  6. Effect of change in macular birefringence imaging protocol on retinal nerve fiber layer thickness parameters using GDx VCC in eyes with macular lesions.

    PubMed

    Dada, Tanuj; Tinwala, Sana I; Dave, Vivek; Agarwal, Anand; Sharma, Reetika; Wadhwani, Meenakshi

    2014-08-01

    This study evaluates the effect of two macular birefringence protocols (bow-tie retardation and irregular macular scan) using GDx VCC on the retinal nerve fiber layer (RNFL) thickness parameters in normal eyes and eyes with macular lesions. In eyes with macular lesions, the standard protocol led to significant overestimation of RNFL thickness which was normalized using the irregular macular pattern protocol. In eyes with normal macula, absolute RNFL thickness values were higher in irregular macular pattern protocols with the difference being statistically significant for all parameters except for inferior average thickness. This has implications for monitoring glaucoma patients who develop macular lesions during the course of their follow-up.

  7. Brane holes

    SciTech Connect

    Frolov, Valeri P.; Mukohyama, Shinji

    2011-02-15

    The aim of this paper is to demonstrate that in models with large extra dimensions under special conditions one can extract information from the interior of 4D black holes. For this purpose we study an induced geometry on a test brane in the background of a higher-dimensional static black string or a black brane. We show that, at the intersection surface of the test brane and the bulk black string or brane, the induced metric has an event horizon, so that the test brane contains a black hole. We call it a brane hole. When the test brane moves with a constant velocity V with respect to the bulk black object, it also has a brane hole, but its gravitational radius r{sub e} is greater than the size of the bulk black string or brane r{sub 0} by the factor (1-V{sup 2}){sup -1}. We show that bulk ''photon'' emitted in the region between r{sub 0} and r{sub e} can meet the test brane again at a point outside r{sub e}. From the point of view of observers on the test brane, the events of emission and capture of the bulk photon are connected by a spacelike curve in the induced geometry. This shows an example in which extra dimensions can be used to extract information from the interior of a lower-dimensional black object. Instead of the bulk black string or brane, one can also consider a bulk geometry without a horizon. We show that nevertheless the induced geometry on the moving test brane can include a brane hole. In such a case the extra dimensions can be used to extract information from the complete region of the brane-hole interior. We discuss thermodynamic properties of brane holes and interesting questions which arise when such an extra-dimensional channel for the information mining exists.

  8. 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.

  9. Macular pigment Raman detector for clinical applications

    PubMed Central

    Ermakov, Igor; Ermakova, Maia; Gellermann, Werner; Bernstein, Paul S.

    2011-01-01

    Clinical studies of carotenoid macular pigments (MP) have been limited by the lack of noninvasive, objective instruments. We introduce a novel noninvasive optical instrument, an MP Raman detector, for assessment of the carotenoid status of the human retina in vivo. The instrument uses resonant excitation of carotenoid molecules in the visible wavelength range, and quantitatively measures the highly specific Raman signals that originate from the single- and double-bond stretch vibrations of the π-conjugated carotenoid molecule’s carbon backbone. The instrument is a robust, compact device and suitable for routine measurements of MP concentrations in a clinical setting. We characterized and tested the instrument in clinical studies of human subjects to validate its function and to begin to establish its role as a possible screening test for macular pathologies. We also show that the MP Raman spectroscopy technology has potential as a novel, highly specific method for rapid screening of carotenoid antioxidant levels in large populations at risk for vision loss from age-related macular degeneration, the leading cause of blindness of the elderly in the developed world. PMID:14715066

  10. Effect of topical isopropyl unoprostone on macular atrophy progression in eyes with exudative age-related macular degeneration

    PubMed Central

    Shiragami, Chieko; Miyake, Masahiro; Fujiwara, Atsushi; Morizane, Yuki; Tsujikawa, Akitaka; Yamashita, Ayana; Shiraga, Fumio

    2017-01-01

    Abstract Background: To evaluate the efficacy and safety of topical isopropyl unoprostone (IU) in treating macular atrophy in age-related macular degeneration (AMD) patients. Methods: Fifty-two AMD patients with macular atrophy were included and randomly assigned (1:1) to the treatment (topical 0.15% IU) or placebo group. Subjects used study eye drops 3 times a day for 54 weeks. The macular atrophy was documented on fundus autofluorescence photographs and measured using RegionFinder. The enlargement rate of macular atrophy and the changes in visual acuity were examined statistically between baseline and 54 weeks. Results: Forty-eight subjects were included in the analyses because 4 subjects withdrew from the study. The differences between the IU and placebo groups in mean and median area of macular atrophy were not statistically significant at baseline. The baseline median lesion size of macular atrophy was 2.33 mm2 in the IU group and 1.63 mm2 in the placebo group (P = 0.51). The intergroup difference in the enlargement ratio of macular atrophy (21 ± 15% in the IU group and 111 ± 96% in the placebo group) was statistically significant (P < 0.001). Additionally, visual acuity tended to improve over baseline in the IU group. No serious adverse events were observed. Conclusions: Topical IU therapy is safe and effective for treating macular atrophy in AMD patients. PMID:28328847

  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. Coronal Holes.

    PubMed

    Cranmer, Steven R

    Coronal holes are the darkest and least active regions of the Sun, as observed both on the solar disk and above the solar limb. Coronal holes are associated with rapidly expanding open magnetic fields and the acceleration of the high-speed solar wind. This paper reviews measurements of the plasma properties in coronal holes and how these measurements are used to reveal details about the physical processes that heat the solar corona and accelerate the solar wind. It is still unknown to what extent the solar wind is fed by flux tubes that remain open (and are energized by footpoint-driven wave-like fluctuations), and to what extent much of the mass and energy is input intermittently from closed loops into the open-field regions. Evidence for both paradigms is summarized in this paper. Special emphasis is also given to spectroscopic and coronagraphic measurements that allow the highly dynamic non-equilibrium evolution of the plasma to be followed as the asymptotic conditions in interplanetary space are established in the extended corona. For example, the importance of kinetic plasma physics and turbulence in coronal holes has been affirmed by surprising measurements from the UVCS instrument on SOHO that heavy ions are heated to hundreds of times the temperatures of protons and electrons. These observations point to specific kinds of collisionless Alfvén wave damping (i.e., ion cyclotron resonance), but complete theoretical models do not yet exist. Despite our incomplete knowledge of the complex multi-scale plasma physics, however, much progress has been made toward the goal of understanding the mechanisms ultimately responsible for producing the observed properties of coronal holes.

  13. 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.

  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. Guided wave interaction with hole damage using the local interaction simulation approach

    NASA Astrophysics Data System (ADS)

    Obenchain, Matthew B.; Cesnik, Carlos E. S.

    2014-12-01

    This paper considers the effects of hole damage on guided wave propagation in isotropic and composite plates using both the local interaction simulation approach (LISA) and experimental methods. Guided wave generation from piezoceramic wafers is modeled using the recently developed LISA hybrid approach. First, holes in isotropic plates are simulated to establish LISA's ability to capture the guided wave scattering effects of various hole sizes. Experimental results are compared with the simulations to aid in evaluating the LISA model. Next, hole damage in cross-ply composite laminates is modeled and compared with experimental results. Various hole sizes and azimuthal locations are simulated to determine the effects of varying those parameters. Results from both the isotropic and composite damage studies clearly display the ability of LISA to model hole damage. Both the simulation and experimental results illustrate the advantages and disadvantages of various sensor locations relative to the actuator and damage locations. Finally, the study shows the ability of the LISA model to capture mode conversions resulting from partial thickness holes.

  16. Depression in Age-Related Macular Degeneration.

    PubMed

    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 diseases. This article discusses the effect of depression on vision-related disability in patients with AMD, suggests methods for screening for depression, and summarizes interventions for preventing depression in this high-risk group.

  17. Diabetic Retinopathy and Diabetic Macular Edema.

    PubMed

    Cohen, Steven R; Gardner, Thomas W

    2016-01-01

    Diabetic retinopathy and diabetic macular edema result from chronic damage to the neurovascular structures of the retina. The pathophysiology of retinal damage remains uncertain but includes metabolic and neuroinflammatory insults. These mechanisms are addressed by intensive metabolic control of the systemic disease and by the use of ocular anti-inflammatory agents, including vascular endothelial growth factor inhibitors and corticosteroids. Improved understanding of the ocular and systemic mechanisms that underlie diabetic retinopathy will lead to improved means to diagnose and treat retinopathy and better maintain vision.

  18. Reduced Macular Vascular Density in Myopic Eyes

    PubMed Central

    Fan, Hua; Chen, Hao-Yu; Ma, Hong-Jie; Chang, Zheng; Yin, Hai-Quan; Ng, Danny Siu-Chun; Cheung, Carol Y; Hu, Shan; Xiang, Xiang; Tang, Shi-Bo; Li, Shuang-Nong

    2017-01-01

    Background: Morphological changes of the vasculature system in patients with myopia have been observed by Doppler ultrasound and fundus fluorescein angiography (FFA); however, these studies have limitations. Doppler ultrasound provides low-resolution images which are mainly obtained from visualized large vessels, and FFA is an invasive examination. Optic coherence tomography (OCT) angiography is a noninvasive, high-resolution measurement for vascular density. The purpose of this study was to investigate the change of vascular density in myopic eyes using OCT angiography. Methods: This cross-sectional study includes a total of 91 eyes from 47 participants including control, moderate, and high myopia that were evaluated by OCT angiography. Patients with myopia were recruited from the Refractive Department, Shenzhen Aier Eye Hospital, from August 5, 2015 to April 1, 2016. Emmetropic eyes were from healthy volunteers. The vascular density at macula and optic disc regions, ganglion cell complex (GCC) thickness, and retinal nerve fiber layer (RNFL) thickness were measured. Their relationships with axial length (AL) and refractive error were analyzed. One-way analysis of variance (ANOVA), Pearson's correlation, and generalized estimating equation were used for statistical analysis. Results: Both superficial and deep macular vascular density were highest in control (25.64% ± 3.76% and 37.12% ± 3.66%, respectively), then in moderate myopia (21.15% ± 5.33% and 35.35% ± 5.50%, respectively), and lowest in high myopia group (19.64% ± 3.87% and 32.81% ± 6.29%, respectively) (F = 13.74 and 4.57, respectively; both P < 0.001). Both superficial (β = −0.850 and 0.460, respectively) and deep (β = −0.766 and 0.396, respectively) macular vascular density were associated with AL and spherical equivalent (all P < 0.001). Superficial macular vascular density was associated with GCC thickness (β = 0.244, P = 0.040), independent of spherical equivalent. The vascular density in

  19. [Age-related macular degeneration (AMD)].

    PubMed

    Michels, Stephan; Kurz-Levin, Malaika

    2009-03-01

    Today age-related macular degeneration (AMD) is the most frequent cause for legal blindness in western industrialized countries. The prevalence of this disease rises with increasing age. A multifactorial pathogenesis of AMD is postulated including genetic predisposition and environmental risk factors. The most relevant modifiable risk factor is smoking. Up to today there is no cure of this chronic disease. Prophylaxis, including a healthy diet and antioxidants as nutrional supplements for selected patients, aims to slow down the disease progression. Significant progress has been made in the treatment of the neovascular form of the disease using inhibitors of the vascular endothelial growth factor (VEGF).

  20. 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.

  1. Clinical Investigation of the Posterior scleral contraction to Treat Macular Traction Maculopathy in Highly Myopic Eyes

    PubMed Central

    Pan, An-Peng; Wan, Ting; Zhu, Shuang-Qian; Dong, Liang; Xue, An-Quan

    2017-01-01

    Myopic traction maculopathy (MTM) can cause vision disabilities in highly myopic eyes. This retrospective case series investigated the clinical outcomes of posterior scleral contraction (PSC) using genipin-cross-linked sclera as the material to treat MTM in highly myopic eyes. In total, 32 eyes from 29 highly myopic patients who underwent PSC for MTM were recruited. The changes in best-corrected visual acuity (BCVA) and axial length were evaluated, macular reattachment and macular hole (MH) closure was assessed by optical coherence tomography, and complications were evaluated. At the final follow-up, the retina was completely reattached in 25 eyes (78.1%), essentially reattached in 4 eyes (12.5%), and partially reattached in 3 eyes (9.4%). The logMAR BCVA improved significantly from 1.18 ± 0.45 preoperatively to 0.87 ± 0.45 postoperatively (P < 0.001). The 32 eyes were further divided into the MH group (16 eyes) and the non-MH group (16 eyes) for comparison. The MH was closed in 9 eyes (56.3%). The retinal reattachment rate was 75.0% in the MH group and 81.25% in the non-MH group, and the logMAR BCVA improved significantly in both groups. The PSC using genipin-cross-linked sclera as the material can effectively treat MTM in highly myopic eyes, and significant visual improvement can be achieved with minimal complications. PMID:28220890

  2. PREFERRED RETINAL LOCUS IN MACULAR DISEASE

    PubMed Central

    GREENSTEIN, VIVIENNE C.; SANTOS, RODRIGO A. V.; TSANG, STEPHEN H.; SMITH, R. THEODORE; BARILE, GAETANO R.; SEIPLE, WILLIAM

    2009-01-01

    Purpose To investigate the location and fixation stability of preferred retinal locations (PRLs) in patients with macular disease, and the relationship among areas of abnormal fundus autofluorescence, the PRL and visual sensitivity. Methods Fifteen patients (15 eyes) were studied. Seven had Stargardt disease, 1 bull’s eye maculopathy, 5 age-related macular degeneration, 1 Best disease, and 1 pattern dystrophy. All tested eyes had areas of abnormal fundus autofluorescence. The PRL was evaluated with fundus photography and the Nidek microperimeter. Visual field sensitivity was measured with the Nidek microperimeter. Results Of the 15 eyes, 4 had foveal and 11 had eccentric fixation. Eccentric PRLs were above the atrophic lesion and their stability did not depend on the degree of eccentricity from the fovea. Visual sensitivity was markedly decreased in locations corresponding to hypofluorescent areas. Sensitivity was not decreased in hyperfluorescent areas corresponding to flecks but was decreased if hyperfluorescence was in the form of dense annuli. Conclusion Eccentric PRLs were in the superior retina in regions of normal fundus autofluorescence. Fixation stability was not correlated with the degree of eccentricity from the fovea. To assess the outcomes of treatment trials it is important to use methods that relate retinal morphology to visual function. PMID:18628727

  3. Bilateral macular injury from a green laser pointer.

    PubMed

    Dirani, Ali; Chelala, Elias; Fadlallah, Ali; Antonios, Rafic; Cherfan, George

    2013-01-01

    We report the case of a 13-year-old boy who had a bilateral macular injury after playing with a green laser pointer for a duration of 1 minute. Clinical examination revealed a decrease in visual acuity and macular injury in both eyes, and imaging investigations revealed a bilateral macular lesion due to exposure to the laser pointer. At 3 months' follow up, visual function had improved but remained partially impaired. This case emphasizes the importance of cautious and appropriate use of laser pointer devices because of the potential vision-threatening hazards induced by mishandling of these devices.

  4. Successful treatment of pseudophakic cystoid macular edema with intravitreal bevacizumab.

    PubMed

    Barone, Antonio; Prascina, Francesco; Russo, Vincenzo; Iaculli, Cristiana; Primavera, Vito; Querques, Giuseppe; Stella, Andrea; Delle Noci, Nicola

    2008-07-01

    A 67-year-old woman developed refractory pseudophakic cystoid macular edema (CME) after uneventful phacoemulsification. Three months after an intravitreal injection of bevacizumab (1.25 mg), the CME was completely resolved, with resultant improvement in visual acuity.

  5. Prevention of age-related macular degeneration

    PubMed Central

    Koo, Simon Chi Yan; Chan, Clement Wai Nang

    2010-01-01

    Age-related macular degeneration (AMD) is one of the leading causes of blindness in the developed world. Although effective treatment modalities such as anti-VEGF treatment have been developed for neovascular AMD, there is still no effective treatment for geographical atrophy, and therefore the most cost-effective management of AMD is to start with prevention. This review looks at current evidence on preventive measures targeted at AMD. Modalities reviewed include (1) nutritional supplements such as the Age-Related Eye Disease Study (AREDS) formula, lutein and zeaxanthin, omega-3 fatty acid, and berry extracts, (2) lifestyle modifications, including smoking and body-mass-index, and (3) filtering sunlight, i.e. sunglasses and blue-blocking intraocular lenses. In summary, the only proven effective preventive measures are stopping smoking and the AREDS formula. PMID:20862519

  6. 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

  7. 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

  8. Idiopathic eruptive macular pigmentation with papillomatosis

    PubMed Central

    Verma, Shikha; Thakur, Binod Kumar

    2011-01-01

    We present a case of an otherwise healthy 10-year-old girl who presented with asymptomatic brown macules over the trunk and proximal extremities, of three months’ duration. The cutaneous examination revealed multiple, dark brown, discrete, round to oval macules and a few mildly elevated lesions over the trunk and proximal limbs. The individual lesion was 1-3 cm in diameter and a few showed velvety appearance over the surface. Darier's sign was negative. The histopathological study from the velvety lesion showed acanthosis, papillomatosis and increased melanin in the basal layer. The upper dermis showed sparse perivascular infiltrate of lymphocytes without any dermal melanophages. It fulfilled the criteria for idiopathic eruptive macular pigmentation with additional histological finding of papillomatosis. PMID:23130237

  9. 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

  10. Perceptual learning in patients with macular degeneration.

    PubMed

    Plank, Tina; Rosengarth, Katharina; Schmalhofer, Carolin; Goldhacker, Markus; Brandl-Rühle, Sabine; Greenlee, Mark W

    2014-01-01

    Patients with age-related macular degeneration (AMD) or hereditary macular dystrophies (JMD) rely on an efficient use of their peripheral visual field. We trained eight AMD and five JMD patients to perform a texture-discrimination task (TDT) at their preferred retinal locus (PRL) used for fixation. Six training sessions of approximately one hour duration were conducted over a period of approximately 3 weeks. Before, during and after training twelve patients and twelve age-matched controls (the data from two controls had to be discarded later) took part in three functional magnetic resonance imaging (fMRI) sessions to assess training-related changes in the BOLD response in early visual cortex. Patients benefited from the training measurements as indexed by significant decrease (p = 0.001) in the stimulus onset asynchrony (SOA) between the presentation of the texture target on background and the visual mask, and in a significant location specific effect of the PRL with respect to hit rate (p = 0.014). The following trends were observed: (i) improvement in Vernier acuity for an eccentric line-bisection task; (ii) positive correlation between the development of BOLD signals in early visual cortex and initial fixation stability (r = 0.531); (iii) positive correlation between the increase in task performance and initial fixation stability (r = 0.730). The first two trends were non-significant, whereas the third trend was significant at p = 0.014, Bonferroni corrected. Consequently, our exploratory study suggests that training on the TDT can enhance eccentric vision in patients with central vision loss. This enhancement is accompanied by a modest alteration in the BOLD response in early visual cortex.

  11. Macular thickness in healthy Saudi adults

    PubMed Central

    Al-Zamil, Waseem M.; Al-Zwaidi, Fahad M.; Yassin, Sanaa A.

    2017-01-01

    Objectives: To determine the macular thickness in the eyes of healthy Saudi adults using spectral-domain optical coherence tomography (SD-OCT). Methods: This is a prospective, cross-sectional study, including 158 healthy participants between August and December 2015. Mean subject age was 29.9 ± 7.85 years old. All participants underwent full ophthalmic evaluation, including SD-OCT imaging, and axial length measurement. Data from the right eye were included. Mean retinal thickness was determined. Correlations between retinal thickness and gender, age, axial length, and spherical equivalence were analyzed. Results: Mean central retinal thickness was 244.76 ± 23.62 µm, mean axial length was 23.8 ± 1.062 mm (range: 20.5-29 mm) and mean spherical equivalent was -0.31 ± 1.75 diopters (D) (range: -5.50 to +4.25 D). Central subfield (CSF) thickness and foveal volume were significantly lower in women than in men (both p<0.001). Data from the various age groups did not show statistically significant differences in the CSF thickness (p=0.389) or foveal volume (p=0.341). A positive correlation between CSF thickness and axial length (p<0.001) was observed. Conclusion: The normal macular thickness values in healthy Saudi individuals is different from that reported in other ethnic groups, as obtained by SD-OCT. Saudi men had thicker CSF than Saudi women and axial length was positively correlated to the central foveal thickness. PMID:28042632

  12. Nonisolated dynamic black holes and white holes

    SciTech Connect

    McClure, M. L.; Anderson, Kaem; Bardahl, Kirk

    2008-05-15

    Modifying the Kerr-Schild transformation used to generate black and white hole spacetimes, new dynamic black and white holes are obtained using a time-dependent Kerr-Schild scalar field. Physical solutions are found for black holes that shrink with time and for white holes that expand with time. The black hole spacetimes are physical only in the vicinity of the black hole, with the physical region increasing in radius with time. The white hole spacetimes are physical throughout. Unlike the standard Schwarzschild solution the singularities are nonisolated, since the time dependence introduces a mass-energy distribution. The surfaces in the metrics where g{sub tt}=g{sup rr}=0 are dynamic, moving inward with time for the black holes and outward for the white holes, which leads to a question of whether these spacetimes truly have event horizons--a problem shared with Vaidya's cosmological black hole spacetimes. By finding a surface that shrinks or expands at the same rate as the null geodesics move, and within which null geodesics move inward or outward faster than the surfaces shrink or expand, respectively, it is verified that these do in fact behave like black and white holes.

  13. 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

  14. [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.

  15. Age related macular degeneration and visual disability.

    PubMed

    Christoforidis, John B; Tecce, Nicola; Dell'Omo, Roberto; Mastropasqua, Rodolfo; Verolino, Marco; Costagliola, Ciro

    2011-02-01

    Age-related macular degeneration (AMD) is the leading cause of central blindness or low vision among the elderly in industrialized countries. AMD is caused by a combination of genetic and environmental factors. Among modifiable environmental risk factors, cigarette smoking has been associated with both the dry and wet forms of AMD and may increase the likelihood of worsening pre-existing AMD. Despite advances, the treatment of AMD has limitations and affected patients are often referred for low vision rehabilitation to help them cope with their remaining eyesight. The characteristic visual impairment for both forms of AMD is loss of central vision (central scotoma). This loss results in severe difficulties with reading that may be only partly compensated by magnifying glasses or screen-projection devices. The loss of central vision associated with the disease has a profound impact on patient quality of life. With progressive central visual loss, patients lose their ability to perform the more complex activities of daily living. Common vision aids include low vision filters, magnifiers, telescopes and electronic aids. Low vision rehabilitation (LVR) is a new subspecialty emerging from the traditional fields of ophthalmology, optometry, occupational therapy, and sociology, with an ever-increasing impact on the usual concepts of research, education, and services for visually impaired patients. Relatively few ophthalmologists practise LVR and fewer still routinely use prismatic image relocation (IR) in AMD patients. IR is a method of stabilizing oculomotor functions with the purpose of promoting better function of preferred retinal loci (PRLs). The aim of vision rehabilitation therapy consists in the achievement of techniques designed to improve PRL usage. The use of PRLs to compensate for diseased foveae has offered hope to these patients in regaining some function. However, in a recently published meta-analysis, prism spectacles were found to be unlikely to be of

  16. 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.

  17. 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.

  18. Intravitreal injection of Bevacizumab in diabetic macular edema

    PubMed Central

    Ateeq, Asim; Tahir, Muhammad Ali; Cheema, Alyscia; Dahri, Arif; Tareen, Saifullah

    2014-01-01

    Objective: To assess the effectiveness of intravitreal injection of Bevacizumab in the treatment of diabetic macular edema. Methods: This case series was conducted at Department of Ophthalmology, Jinnah Post Graduate Medical Centre (JPMC), Karachi. The duration of study was six months from May 26, 2011 to November 25, 2011. The study group comprised of 54 patients of the Diabetic Macular Edema (DME). Intravitreal injection of 1.25 mg of bevacizumab (Avastin) was injected 3.5 mm from the limbus under topical anaesthetic drops. Post procedure follow up was scheduled on 1st post procedure day and after one month. Post procedure Optical Coherence tomography (OCT) was performed in all patients 1 week before and 1st month after 1st injection. The results were statistically analyzed through SPSS 17. Results: Out of the 54 Eyes of 54 Patients who were given the Intravitreal injection of Avastin (Bevacizumab), 43 Eyes (79.6%) showed more than ten percent decrease in macular thickness from pre-injection thickness, 10 Eyes (18.5%) showed less than ten percent decrease and 1 Eye (1.9%) showed increase in macular thickness post operatively after one month. Conclusions: Intravitreal injection of Bevacizumab (Avastin) is effective in the treatment of diabetic macular edema. PMID:25674143

  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 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.

  1. Managed care implications of diabetic macular edema.

    PubMed

    Holekamp, Nancy M

    2016-07-01

    Diabetic retinopathy (DR) is both the leading cause of blindness among adults aged 20 to 74 in the United States, and the leading ocular complication associated with diabetes mellitus (DM). An estimated 4.4% of adults with DM over 40 years of age have the more advanced form of DR: diabetic macular edema (DME), which significantly increases the risk of blindness. Medical costs for Medicare patients with DME are a third higher than for patients without DME. The majority of these costs stem from other DM-related complications, as DME is a marker for poorly controlled DM overall. Commercially insured patients with DME incur direct and indirect costs up to 75% higher than for those with DR without DME. Early detection, treatment, and improved glycemic control can limit the onset or progression of microvascular complications of DR, including DME, resulting in significant savings for payers. However, there are significant gaps in adherence to national guidelines regarding DM control and early identification of DR. In addition, patients face several barriers to screening. Improving screening for and management of early DR could decrease progression to DME, which would provide significant savings for payers, as well as improve the quality of care and outcomes for patients with DM. Managed care organizations and employers should also consider the cost-effectiveness of currently available treatments for DME: focal laser photocoagulation, vascular endothelial growth factor inhibitors, and intravitreal corticosteroid injections and implants, in their formulary design; they should also identify opportunities to improve patient adherence to treatment.

  2. 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.

  3. 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].

  4. Animal models of age related macular degeneration.

    PubMed

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

    2012-08-01

    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.

  5. 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

  6. 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

  7. Relationship between macular pigment and visual function in subjects with early age-related macular degeneration

    PubMed Central

    Nolan, John M; Peto, Tunde; Stack, Jim; Leung, Irene; Corcoran, Laura; Beatty, Stephen

    2017-01-01

    Purpose To investigate the relationship between macular pigment (MP) and visual function in subjects with early age-related macular degeneration (AMD). Methods 121 subjects with early AMD enrolled as part of the Central Retinal Enrichment Supplementation Trial (CREST; ISRCTN13894787) were assessed using a range of psychophysical measures of visual function, including best corrected visual acuity (BCVA), letter contrast sensitivity (CS), mesopic and photopic CS, mesopic and photopic glare disability (GD), photostress recovery time (PRT), reading performance and subjective visual function, using the National Eye Institute Visual Function Questionnaire-25 (NEI VFQ-25). MP was measured using customised heterochromatic flicker photometry. Results Letter CS, mesopic and photopic CS, photopic GD and mean reading speed were each significantly (p<0.05) associated with MP across a range of retinal eccentricities, and these statistically significant relationships persisted after controlling for age, sex and cataract grade. BCVA, NEI VFQ-25 score, PRT and mesopic GD were unrelated to MP after controlling for age, sex and cataract grade (p>0.05, for all). Conclusions MP relates positively to many measures of visual function in unsupplemented subjects with early AMD. The CREST trial will investigate whether enrichment of MP influences visual function among those afflicted with this condition. Trial registration number ISRCTN13894787. PMID:27091854

  8. 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

  9. Gene therapy in age related macular degeneration and hereditary macular disorders.

    PubMed

    Kinnunen, Kati; Yla-Herttuala, Seppo

    2012-06-01

    In ophthalmology, administration of the therapeutic agent can be difficult due to the tight barriers in the eye. Multiple injections may be needed to allow the therapeutic agent to reach adequate levels in retina and choroidea which may increase the risk of complications including endophthalmitis, cataract and haemorrhages. Optimal methods for the delivery of therapeutic agents to the posterior segments of the eye have not yet been developed. Gene therapy offers an alternative where the therapeutic protein or proteins can be induced in the target tissue for a prolonged period of time after a single injection. The eye is a promising target for gene therapy due to its small size and tissue boundaries preventing leakage of the therapeutic material to other tissues or systemic circulation. However, most of the work in ocular gene therapy is still at the preclinical phase; only three vectors have reached phase 1/2 clinical trials. This review summarizes basic principles and current status of gene therapy in age related macular degeneration and hereditary macular disorders.

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

    PubMed

    Das, Undurti N

    2016-10-01

    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.

  11. [Macular threshold after ECCE and posterior chamber IOL implantation].

    PubMed

    Baltatzis, S; Georgopoulos, G; Andreanos, D

    1989-01-01

    In the present paper, the macular threshold after ECCE and posterior chamber intraocular lens implantation, was studied in an effort to determine the time period needed for full postoperative recovery of macular function. We evaluated 22 eyes in 20 patients who underwent extracapsular cataract extraction and posterior chamber IOL implantation. There were 12 men and 8 women between the ages of 40 and 62 years with mean age of 53 years. Postoperative visual field testing was performed within the central 4 degrees with an automated static perimeter (Humphrey Visual Field Analyser), using a macular threshold test pattern. It has been established that central retinal sensitivity in pseudophakia shows a postoperative decrease and consequently recovers to almost normal levels within one month. The exact cause of this reduction remains under discussion and further control mainly with fluorescein angiography is necessary.

  12. Developments in age-related macular degeneration: Diagnosis and treatment.

    PubMed

    Kaufman, Steven R

    2009-03-01

    Age-related macular degeneration (ARMD) is the leading cause of legal blindness of Americans over age 65 years. Severe loss of vision is usually due to exudative ARMD, of which there are about 200,000 new cases in the United States annually. Until recently, only a small fraction of patients benefited from treatment, but advances in the early diagnosis of the disease and major developments in therapy have substantially improved the prognosis of patients with ARMD. Because visual loss substantially reduces quality of life, effective management of ARMD will have increasing public health importance as the population ages. The American Academy of Ophthalmology recommends that people over age 65 years should have a comprehensive eye examination every 1 to 2 years to check for cataracts, macular degeneration, glaucoma, and other conditions. Those who complain of difficulty reading, driving at night, or adapting from sunlight to indoor lighting might have macular degeneration.

  13. [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.

  14. Bilateral choroidal excavation in best vitelliform macular dystrophy.

    PubMed

    Parodi, Maurizio Battaglia; Zucchiatti, Ilaria; Fasce, Francesco; Bandello, Francesco

    2014-02-14

    Focal choroidal excavation (FCE) has recently been described as one or more localized areas of choroidal excavation on spectral-domain optical coherence tomography (SD-OCT). The authors describe a case of bilateral FCE in Best vitelliform macular dystrophy (VMD). SD-OCT revealed FCE in both eyes characterized by interruption of the internal segment-outer segment junction and the presence of subretinal hyporeflective space. This is the first report describing bilateral FCE in a distinct macular disorder and specifically with VMD. Future investigations are warranted to ascertain the involvement of other macular dystrophies with atrophic evolution and the impact of FCE on the clinical course. [Ophthalmic Surg Lasers Imaging Retina. 2014;45:e8-e10.].

  15. Juvenile-Onset Macular Degeneration and Allied Disorders

    PubMed Central

    North, Victoria; Gelman, Rony; Tsang, Stephen H.

    2015-01-01

    While age-related macular degeneration (AMD) is a leading cause of central vision loss among the elderly, many inherited diseases that present earlier in life share features of AMD. These diseases of juvenile-onset macular degeneration include Stargardt disease, Best disease, retinitis pigmentosa, X-linked retinoschisis, and other allied disorders. In particular, they can be accompanied by the appearance of drusen, geographic atrophy, macular hyperpigmentation, choroidal neovascularization, and disciform scarring just as in AMD, and often may be confused for the adult form of the disease. Diagnosis based on funduscopic findings alone can be challenging. However, the use of diagnostic studies such as electroretinography, electrooculography, optical coherence tomography, and fundus autofluorescence in conjunction with genetic testing can lead to an accurate diagnosis. PMID:24732760

  16. Bimatoprost Induced Serous Macular Detachment after Cataract Surgery

    PubMed Central

    Kaliaperumal, Subashini; Deb, Amit Kumar; Babu, K. Ramesh; Srinivasan, Renuka

    2016-01-01

    We report a case of bimatoprost induced serous macular detachment and choroidal folds following uneventful cataract surgery. A 66-year-old male using topical bimatoprost in both eyes for open angle glaucoma underwent uneventful cataract surgery in the right eye. Postoperatively, he was restarted on topical bimatoprost and antibiotic-steroids combination drops. One week after surgery, he presented with conjunctival hyperemia, serous macular detachment, and choroidal folds at the posterior pole. Fundus fluorescein angiography showed perifoveal leaks in early stage with pooling of dye in late stage. Discontinuation of bimatoprost led to resolution of serous detachment and choroidal folds within 3 weeks with significant improvement in visual acuity. Occurrence of serous macular detachment and choroidal folds in this case could be probably related to the proinflammatory property of bimatoprost. Hence, it should be used with caution in the immediate postoperative period after cataract surgery. PMID:27957367

  17. Age-related macular degeneration: current treatment and future options.

    PubMed

    Moutray, Tanya; Chakravarthy, Usha

    2011-09-01

    Age-related macular degeneration is the leading cause of visual impairment among older adults in the developed world. Epidemiological studies have revealed a number of genetic, ocular and environmental risk factors for this condition, which can be addressed by disease reduction strategies. We discuss the various treatment options for dry and exudative age-related macular degeneration available and explain how the recommended treatment depends on the exact type, location and extent of the degeneration. Currently, vascular endothelial growth factor (VEGF) inhibition therapy is the best available treatment for exudative age-related macular degeneration but is limited by the need for repeated intravitreal injections. The current treatment regime is being refined through research on optimal treatment frequency and duration and type of anti-VEGF drug. Different modes of drug delivery are being developed and in the future other methods of VEGF inhibition may be used.

  18. A Dancing Black Hole

    NASA Astrophysics Data System (ADS)

    Shoemaker, Deirdre; Smith, Kenneth; Schnetter, Erik; Fiske, David; Laguna, Pablo; Pullin, Jorge

    2002-04-01

    Recently, stationary black holes have been successfully simulated for up to times of approximately 600-1000M, where M is the mass of the black hole. Considering that the expected burst of gravitational radiation from a binary black hole merger would last approximately 200-500M, black hole codes are approaching the point where simulations of mergers may be feasible. We will present two types of simulations of single black holes obtained with a code based on the Baumgarte-Shapiro-Shibata-Nakamura formulation of the Einstein evolution equations. One type of simulations addresses the stability properties of stationary black hole evolutions. The second type of simulations demonstrates the ability of our code to move a black hole through the computational domain. This is accomplished by shifting the stationary black hole solution to a coordinate system in which the location of the black hole is time dependent.

  19. Macular pigmentation of uncertain aetiology revisited: two case reports and a proposed algorithm for clinical classification.

    PubMed

    Chandran, Veena; Kumarasinghe, Sujith Prasad

    2017-02-01

    Ashy dermatosis, erythema dyschromicum perstans, lichen planus pigmentosus and idiopathic eruptive macular pigmentation are various types of acquired macular hyperpigmentation disorders of the skin described in literature. However, a global consensus on the definitions of these entities is lacking. We report two cases of acquired macular (hyper)pigmentation of uncertain aetiology diagnosed as ashy dermatosis and attempt to clarify the various confusing nosologies based on existing literature. We infer that acquired small and large macular pigmentation of uncertain aetiology should be considered separate from that associated with lichen planus. We also propose a diagnostic algorithm for patients with acquired macular hyperpigmentation.

  20. CKD increases the risk of age-related macular degeneration.

    PubMed

    Liew, Gerald; Mitchell, Paul; Wong, Tien Yin; Iyengar, Sudha K; Wang, Jie Jin

    2008-04-01

    Age-related macular degeneration is the leading cause of irreversible blindness in the United States and often coexists with chronic kidney disease. Both conditions share common genetic and environmental risk factors. A total of 1183 participants aged 54+ were examined in the population-based, prospective cohort Blue Mountains Eye Study (Australia) to determine if chronic kidney disease increases the risk of age-related macular degeneration. Moderate chronic kidney disease (estimated glomerular filtration rate < 60 ml/min per 1.73 m(2) based on the Cockcroft-Gault equation) was present in 24% of the population (286 of 1183). The 5-yr incidence of early age-related macular degeneration was 3.9% in participants with no/mild chronic kidney disease (35 of 897) and 17.5% in those with moderate chronic kidney disease (50 of 286). After adjusting for age, sex, cigarette smoking, hypertension, complement factor H polymorphism, and other risk factors, persons with moderate chronic kidney disease were 3 times more likely to develop early age-related macular degeneration than persons with no/mild chronic kidney disease (odds ratio = 3.2; 95% confidence interval, 1.8 to 5.7, P < 0.0001). Each SD (14.8 ml/min per 1.73 m(2)) decrease in Cockcroft-Gault estimated glomerular filtration rate was associated with a doubling of the adjusted risk for early age-related macular degeneration (odds ratio = 2.0; 95% confidence interval, 1.5 to 2.8, P < 0.0001). In conclusion, persons with chronic kidney disease have a higher risk of early age-related macular degeneration, suggesting the possibility of shared pathophysiologic mechanisms between the two conditions.

  1. 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

  2. [Detection of cystoid macular edema with orally administered fluorescein].

    PubMed

    Hütz, W; Hessemer, V; Jacobi, K W

    1989-10-01

    To detect cystoid macular edema after extracapsular cataract extraction, the authors used indirect ophthalmoscopy after oral application of fluorescein, rather than intravenous fluorescein angiography. The patients drank 10-20 ml 10% fluorescein sodium in 250 ml orange juice. Ophthalmoscopy was performed 30-45 minutes later using an exciter filter. Twenty-five patients with a tentative clinical diagnosis of cystoid macular edema were examined in this way. In six of them a manifest edema was detected. The results were confirmed by intravenous fluorescein angiography.

  3. Use of antivascular endothelial growth factor for diabetic macular edema

    PubMed Central

    Karim, Rushmia; Tang, Benjamin

    2010-01-01

    Background Diabetic macular edema (DME) is one of the manifestations of diabetic retinopathy leading to loss of central vision and visual acuity. It manifests itself with swelling around the central part of the retina, the area responsible for sharp vision. Current treatment includes laser therapy and intravitreal steroids with preventative measures including diabetes control. No one treatment has guaranteed control of diabetic macular edema which leads to deteriorating visual acuity, function and quality of life in patients. Vascular endothelial growth factor (VEGF) has been shown to be a critical stimulus in the pathogenesis of macular edema secondary to diabetes.1 Antiangiogenic therapy encompassed treatment with anti-VEGF which inhibits VEGF-driven neovascularization hence macular edema leading to decreased visual acuity. Objective For this review, we evaluated the effectiveness of intravitreal anti-VEGF in treating DME. Data sources We identified five trials (n = 525) using electronic databases (Cochrane Central Register of Controlled Trials [Central], Medline®, and Excerpta Medica Database [EMBASE®]) in October 2008, supplemented by hand searching of reference lists, review articles, and conference abstracts. Methods We included all randomized clinical trials (RCTs) evaluating any form of intravitreal anti-VEGF for treating DME. The main outcome factor was change in best-corrected visual acuity and central macular thickness. One author assessed eligibility, methodological quality, and extracted data. Meta analysis was performed when appropriate. Results We included three trials of adequate methodological quality in our meta-analysis. Patients treated with anti-VEGF showed improvement in visual acuity of −0.17 (95% confidence interval [CI]: −0.23, −0.10) and central macular thickness −84.69 (95% CI: −117.09, −52.30). Patients treated with combined anti-VEGF and intravitreal triamcinolone showed improvement of visual acuity of −0.19 (95% CI:

  4. 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.

  5. 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

  6. Rehabilitation Approaches in Macular Degeneration Patients

    PubMed Central

    Maniglia, Marcello; Cottereau, Benoit R.; Soler, Vincent; Trotter, Yves

    2016-01-01

    Age related macular degeneration (AMD) is a visual disease that affects elderly population. It entails a progressive loss of central vision whose consequences are dramatic for the patient’s quality of life. Current rehabilitation programs are restricted to technical aids based on visual devices. They only temporarily improve specific visual functions such as reading skills. Considering the rapid increase of the aging population worldwide, it is crucial to intensify clinical research on AMD in order to develop simple and efficient methods that improve the patient’s visual performances in many different contexts. One very promising approach to face this challenge is based on perceptual learning (PL). Through intensive practice, PL can induce neural plasticity in sensory cortices and result in long-lasting enhancements for various perceptual tasks in both normal and visually impaired populations. A growing number of studies showed how appropriate PL protocols improve visual functions in visual disorders, namely amblyopia, presbyopia or myopia. In order to successfully apply these approaches to more severe conditions such as AMD, numerous challenges have to be overcome. Indeed, the overall elderly age of patients and the reduced cortical surface that is devoted to peripheral vision potentially limit neural plasticity in this population. In addition, ocular fixation becomes much less stable because patients have to rely on peripheral fixation spots outside the scotoma whose size keeps on evolving. The aim of this review article is to discuss the recent literature on this topic and to offer a unified approach for developing new rehabilitation programs of AMD using PL. We argue that with an appropriate experimental and training protocol that is adapted to each patient needs, PL can offer fascinating opportunities for the development of simple, non-expensive rehabilitation approaches a large spectrum of visual functions in AMD patients. PMID:28082876

  7. Rehabilitation Approaches in Macular Degeneration Patients.

    PubMed

    Maniglia, Marcello; Cottereau, Benoit R; Soler, Vincent; Trotter, Yves

    2016-01-01

    Age related macular degeneration (AMD) is a visual disease that affects elderly population. It entails a progressive loss of central vision whose consequences are dramatic for the patient's quality of life. Current rehabilitation programs are restricted to technical aids based on visual devices. They only temporarily improve specific visual functions such as reading skills. Considering the rapid increase of the aging population worldwide, it is crucial to intensify clinical research on AMD in order to develop simple and efficient methods that improve the patient's visual performances in many different contexts. One very promising approach to face this challenge is based on perceptual learning (PL). Through intensive practice, PL can induce neural plasticity in sensory cortices and result in long-lasting enhancements for various perceptual tasks in both normal and visually impaired populations. A growing number of studies showed how appropriate PL protocols improve visual functions in visual disorders, namely amblyopia, presbyopia or myopia. In order to successfully apply these approaches to more severe conditions such as AMD, numerous challenges have to be overcome. Indeed, the overall elderly age of patients and the reduced cortical surface that is devoted to peripheral vision potentially limit neural plasticity in this population. In addition, ocular fixation becomes much less stable because patients have to rely on peripheral fixation spots outside the scotoma whose size keeps on evolving. The aim of this review article is to discuss the recent literature on this topic and to offer a unified approach for developing new rehabilitation programs of AMD using PL. We argue that with an appropriate experimental and training protocol that is adapted to each patient needs, PL can offer fascinating opportunities for the development of simple, non-expensive rehabilitation approaches a large spectrum of visual functions in AMD patients.

  8. Treatment of macular degeneration, according to Bangerter.

    PubMed

    Teichmann, K D

    1997-10-30

    Age-related macular degeneration (AMD) is a common cause of visual loss among elderly patients. Although some risk factors have been determined, the ultimate cause of the disease is not known. For a long time, therapeutic nihilism has been the rule among ophthalmologists confronted with such patients. Bangerter has not shared this attitude, especially since the time that he incidentally discovered, more than 40 years ago, the beneficial effects of radiotherapy, in discouraging the growth of new vessels at the posterior pole of the eye. A variety of approaches are combined and used by Bangerter in the treatment of the different types of AMD, including retrobulbar injections of either vasodilating medications (in the dry - or atrophic - type) or corticosteroids (in the wet - or exudative - type), general medical measures aimed at improving metabolic and vascular functions such as supplementation with trace elements, antioxidants, and vitamins; ozone therapy; advice to increase physical fitness, improve nutrition, and abstain from smoking; and protection from excessive light exposure. Being convinced of the usefulness of his type of combination treatment, he has always rejected undertaking controlled clinical trials, of only single aspects of the therapy, as unethical and invalid. For this reason, scientific journals have not proven cooperative in several attempts at publishing his results, as collected in retrospective surveys. Recently, however, some of the several approaches combined by Bangerter in treating AMD have been pronounced effective by other investigators. We present here an overview of his treatment approaches, as few people are aware of them, to clear up misconceptions and to set records straight.

  9. Partial-Thickness Grooves In A VBL Memory Device

    NASA Technical Reports Server (NTRS)

    Katti, Romney R.; Wu, Jiin-Chuan; Stadler, Henry L.

    1994-01-01

    Bias magnetic fields tailored to match those needed elsewhere in device. Grooves through part of thickness of magnetic garnet storage layer of vertical-Bloch-line (VBL) memory device used to confine magnetic bubble and stripe domains in desired storage areas. VBL-memory concept described in "Vertical-Bloch-Line Memory" (NPO-18467).

  10. Partial-thickness corneal tissue restoration after a chemical burn

    PubMed Central

    Galan, Alessandro; Catania, Anton Giulio; Giudice, Giuseppe Lo

    2016-01-01

    Purpose We describe a case of full-thickness corneal restoration after an acute corneal burn with an acid agent. Methods A 32-year-old male reported painful discomfort, redness, photophobia, and a decrease in visual acuity in the left eye after a unilateral burn with an acid agent. Slit-lamp examination revealed massive corneal melting involving necrotic sequestrum of the entire corneal surface. Surgical approach was carried out in order to preserve residual ocular tissues. Results Extensive corneal–conjunctival layer curettage of the necrotic tissue was performed showing perfectly clear undamaged deep lamellar corneal layers. The patient underwent multilayered amniotic membrane transplantation and total capsular–conjunctival flap in order to preserve ocular tissue from further melting or corneal perforation. A complete and spontaneous “restitutio ad integrum” of the corneal layers was shown during the follow-up. The cornea was perfectly clear with restored normal anatomical architecture. Conclusion In this case, a spontaneous full-thickness corneal tissue restoration occurred after an acute chemical burn. Studies about the mechanisms whereby different cells interact and replicate within the stroma may unveil the biology behind corneal regeneration and transparency. PMID:27194918

  11. 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...

  12. Black hole hair removal

    NASA Astrophysics Data System (ADS)

    Banerjee, Nabamita; Mandal, Ipsita; Sen, Ashoke

    2009-07-01

    Macroscopic entropy of an extremal black hole is expected to be determined completely by its near horizon geometry. Thus two black holes with identical near horizon geometries should have identical macroscopic entropy, and the expected equality between macroscopic and microscopic entropies will then imply that they have identical degeneracies of microstates. An apparent counterexample is provided by the 4D-5D lift relating BMPV black hole to a four dimensional black hole. The two black holes have identical near horizon geometries but different microscopic spectrum. We suggest that this discrepancy can be accounted for by black hole hair — degrees of freedom living outside the horizon and contributing to the degeneracies. We identify these degrees of freedom for both the four and the five dimensional black holes and show that after their contributions are removed from the microscopic degeneracies of the respective systems, the result for the four and five dimensional black holes match exactly.

  13. Long-term effectiveness of ranibizumab for age-related macular degeneration and diabetic macular edema.

    PubMed

    Fong, Angie H C; Lai, Timothy Y Y

    2013-01-01

    Neovascular age-related macular degeneration (AMD) and diabetic macular edema (DME) are major causes of visual impairment in the elderly population worldwide. With the aging population, the prevalence of neovascular AMD and DME has increased substantially over the recent years. Vascular endothelial growth factor (VEGF) has been implicated as playing an important role in the pathogenesis of both neovascular AMD and DME. Since its introduction in 2006, ranibizumab, a recombinant, humanized, monoclonal antibody fragment against all isoforms of VEGF-A, has revolutionized the treatment of neovascular AMD and DME. The efficacy and safety of ranibizumab in neovascular AMD has been demonstrated in the ANCHOR and MARINA trials. Further studies including the PIER, PrONTO, and SUSTAIN trials have also evaluated the optimal dosing regimen of ranibizumab in neovascular AMD. The CATT and IVAN trials compared the safety and efficacy of ranibizumab with off-label use of bevacizumab. Studies such as SUSTAIN and HORIZON have shown that ranibizumab has a good safety profile and is well tolerated for over 4 years with very few serious ocular and systemic adverse events. For DME, Phase II RESOLVE study and Phase III RISE and RIDE studies have demonstrated superiority of ranibizumab treatment in improving vision over placebo controls. Phase II READ and Phase III RESOLVE and REVEAL studies have shown that ranibizumab is more effective both as monotherapy and in combination with laser compared with laser monotherapy. The 3-year results from the DRCRnet protocol I study found that ranibizumab with deferred laser resulted in better long-term visual outcome compared with ranibizumab with prompt laser. This review summarizes various important clinical trials on the long-term efficacy and safety of ranibizumab in the treatment of neovascular AMD and DME. The pharmacological properties of ranibizumab, its cost effectiveness, and impact on quality of life will also be discussed.

  14. Aqueous cytokine levels are associated with reduced macular thickness after intravitreal ranibizumab for diabetic macular edema

    PubMed Central

    Kato, Satoshi; Araki, Fumiyuki; Ueta, Takashi; Miyaji, Tempei; Yamaguchi, Takuhiro

    2017-01-01

    Purpose It is controversial whether the administration of anti-vascular endothelial growth factor drugs for diabetic macular edema (DME) affects intraocular inflammatory cytokines. In this study, we measured cytokine concentration in aqueous humor before and after intravitreal injection of ranibizumab (IVR). The aim was to determine changes in cytokine concentration and their effects on DME reduction. Methods Twelve patients (13 eyes) with DME received two IVR (0.5 mg) with a 1 month interval, and a total of 26 aqueous humor samples were obtained. Macular thickness was measured with an optical coherence tomography (OCT) using thickness-map mode with an Early Treatment Diabetic Retinopathy Study (ETDRS) 9-zone grid that was divided into two zones: a central circle with a diameter of 1 mm (zone1); and an outer circle with a diameter of 6 mm (zone2). Results The concentration of eotaxin-1 in aqueous humor samples decreased significantly after IVR. Baseline cytokine concentration was associated with IVR-induced DME reduction. In zone1, higher baseline concentration of interferon-induced protein (IP)-10, and in zone 2, higher baseline concentration of granulocyte-macrophage colony-stimulating factor, IP-10, and tumor necrosis factor (TNF) α; and lower baseline concentration of eotaxin-1, interleukin (IL)-5, and IL-8 were associated with improved DME. Cytokine changes were associated with IVR-induced DME reduction. In zone1, lower concentration of IP-10 compared to baseline or higher concentration of macrophage inflammatory protein (MIP) -α, and in zone 2, lower concentration of IL-5 compared to baseline, IL-8, and IP-10 or higher concentration of eotaxin-1 and MIP-1β were associated with improved DME. Conclusions These findings suggest that ranibizumab affects the concentration of cytokines in aqueous humor. Various cytokines contribute to a decrease in retinal thickness, both in the center of the macula and in a larger area of the retina. PMID:28346545

  15. Black Hole Thermodynamics

    NASA Astrophysics Data System (ADS)

    Israel, Werner

    This chapter reviews the conceptual developments on black hole thermodynamics and the attempts to determine the origin of black hole entropy in terms of their horizon area. The brick wall model and an operational approach are discussed. An attempt to understand at the microlevel how the quantum black hole acquires its thermal properties is included. The chapter concludes with some remarks on the extension of these techniques to describing the dynamical process of black hole evaporation.

  16. 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.

  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: report on two cases.

    PubMed

    Grover, Sanjiv; Basu, Atoshi

    2010-01-01

    Idiopathic eruptive macular pigmentation (IEMP) is a rather under-reported condition of unknown etiology. Clinically consisting of benign hyperpigmented macules, the condition is characterized histopathologically by dermal melanization. It must be differentiated from lichen planus pigmentosus, erythema dyschromicum perstans, fixed drug eruption and mastocytosis.

  19. IDIOPATHIC ERUPTIVE MACULAR PIGMENTATION: REPORT ON TWO CASES

    PubMed Central

    Grover, Sanjiv; Basu, Atoshi

    2010-01-01

    Idiopathic eruptive macular pigmentation (IEMP) is a rather under-reported condition of unknown etiology. Clinically consisting of benign hyperpigmented macules, the condition is characterized histopathologically by dermal melanization. It must be differentiated from lichen planus pigmentosus, erythema dyschromicum perstans, fixed drug eruption and mastocytosis. PMID:21063525

  20. Unusual Presentation of Type 1 Idiopathic Macular Telangiectasia

    PubMed Central

    Denis, Philippe

    2017-01-01

    Purpose. To report unusual presentation of type 1A idiopathic macular telangiectasia (IMT). Methods. Two middle-aged women with bilateral IMT were examined. Results. Both patients presented with a gradual vision loss in both eyes. Fundus examination was unremarkable in one case and showed small macular telangiectasia in both eyes in the other case. Fluorescein angiography (FA) revealed early bilateral macular punctuated hyperfluorescence corresponding to the dilated capillaries in both cases. FA and fundus examination confirmed also the absence of vascular abnormalities in the middle or anterior fundus periphery in one case. Spectral-domain optical coherence tomography (SD-OCT) showed cystoid macular edema in both cases. No signs of retinal vein occlusions were detected in both cases and other differential diagnoses were excluded. Based on these findings, the patients were diagnosed with bilateral type 1A IMT according to Gass and Blodi classification and were treated with intravitreal antivascular endothelial growth factor (anti-VEGF) injections and focal laser photocoagulation. Twelve months later, SD-OCT revealed partial regression of the exudative signs and significant VA improvement. Conclusion. We described two patients with an unusual presentation of type 1A IMT with bilateral presentation, affecting two middle-aged women, with occult and without peripheral involvement in one case. The description of more cases of bilateral type 1 IMT should be helpful to more precisely define the pathophysiologic mechanism that could be different from a localized Coats' disease of the macula area. PMID:28203470

  1. Macular folds: an unusual association in topiramate toxicity.

    PubMed

    Kumar, Mukesh; Kesarwani, Siddharth; Rao, Aparna; Garnaik, Anshuman

    2012-07-01

    We report two uncommon cases of acute onset myopia with macular folds following use of topiramate. A 25-year-old woman, with no prior history of glasses, taking topiramate for recurrent headaches, presented with decreased vision. On examination, she was found to have a refractive error of -5.00 DS in both eyes and intraocular pressure of 10 mmHg and 6 mmHg in the right and left eyes, respectively. She had closed angles on gonioscopy, ciliary effusion on ultrasonic biomicroscopy with inner limiting membrane folds in the macula in both eyes. She was on anti-glaucoma medication when she presented to us. A 20-year-old woman presented with acute headache and decreased vision following use of topiramate for treatment of migraine. On examination, her intraocular pressure was 25 mmHg in both eyes with closed angles on gonioscopy, a refractive error of -4.50 DS and prominent macular folds with no fluid in both eyes. There was complete resolution of macular folds and angle-closure attack after discontinuation of topiramate and conservative treatment with topical steroids and cycloplegics in both eyes. Topiramate toxicity may present with macular folds associated with angle-closure glaucoma. Folds in the inner limiting membrane might give a clue to choroidal effusion as the cause for this presentation. The symptoms resolved on the discontinuation of topiramate.

  2. Diagnosing and monitoring diabetic macular edema: structural and functional tests.

    PubMed

    Midena, Edoardo; Vujosevic, Stela

    2015-10-01

    Diabetic macular edema remains a major cause of visual impairment in adults despite the use of intensive glycemic control, photocoagulation therapy and new intravitreal drugs in the treatment of this disease. Although early diagnosis and treatment lead to better results, we still have patients who become legally blind. Therefore, better structural and functional characterization of this disease is necessary in order to customize treatment.

  3. 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…

  4. 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…

  5. Treatment of dry age-related macular degeneration with dobesilate

    PubMed Central

    Cuevas, P; Outeiriño, L A; Angulo, J; Giménez-Gallego, G

    2012-01-01

    The authors present anatomical and functional evidences of dry age-macular degeneration improvement, after intravitreal treatment with dobesilate. Main outcomes measures were normalisation of retinal structure and function, assessed by optical coherence tomography, fundus-monitored microperimetry, electrophysiology and visual acuity. The effect might be related to the normalisation of the outer retinal architecture. PMID:22729337

  6. 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.

  7. Vitamin E supplementation and macular degeneration: randomised controlled trial

    PubMed Central

    Taylor, Hugh R; Tikellis, Gabriella; Robman, Luba D; McCarty, Catherine A; McNeil, John J

    2002-01-01

    Objective To determine whether vitamin E supplementation influences the incidence or rate of progression of age related maculopathy (AMD). Design Prospective randomised placebo controlled clinical trial. Setting An urban study centre in a residential area supervised by university research staff. Participants 1193 healthy volunteers aged between 55 and 80 years; 73% completed the trial on full protocol. Interventions Vitamin E 500 IU or placebo daily for four years. Main outcome measures Primary outcome: development of early age related macular degeneration in retinal photographs. Other measures included alternative definitions of age related macular degeneration, progression, changes in component features, visual acuity, and visual function Results The incidence of early age related macular degeneration (early AMD 3) was 8.6% in those receiving vitamin E versus 8.1% in those on placebo (relative risk 1.05, 95% confidence interval 0.69 to 1.61). For late disease the incidence was 0.8% versus 0.6% (1.36, 0.67 to 2.77). Further analysis showed no consistent differences in secondary outcomes. Conclusion Daily supplement with vitamin E supplement does not prevent the development or progression of early or later stages of age related macular degeneration. What is already known on this topicAge related macular degeneration is the leading cause of loss of vision and blindness in elderly people; for people aged ⩾90 years, two out of every three will be affected and one in four will become blindCurrently, there are no methods of prevention or treatment in most cases, though a third of cases are due to cigarette smokingAntioxidant vitamins have been suggested as a possible preventionWhat this study addsDaily supplementation with 500 mg vitamin E for four years did not alter the incidence or progression of AMD PMID:12098721

  8. Macular ischaemia: a contraindication for anti-VEGF treatment in retinal vascular disease?

    PubMed

    Manousaridis, Kleanthis; Talks, James

    2012-02-01

    Anti-vascular endothelial growth factor (anti-VEGF) therapy has been shown to be effective at improving vision in patients with macular oedema due to diabetic retinopathy and vein occlusions, but blocking VEGF at least in theory could be detrimental to vascular integrity. For this reason, some patients with macular ischaemia were excluded from studies showing the effectiveness of therapy. A considerable number of patients present with mixed pathology of macular oedema and macular ischaemia and it is often impossible to determine the degree to which ischaemia accounts for decreased vision. In this review, the authors have dealt with the specific question of whether or not there is evidence to support potential worsening of the macular perfusion and visual function after anti-VEGF treatment with bevacizumab or ranibizumab for macular oedema secondary to diabetic retinopathy or retinal vein occlusions, especially if there is coexisting macular ischaemia. The authors conclude that anti-VEGF therapy rarely seems to further compromise the retinal circulation; however, worsening of macular ischaemia in the long term cannot be definitely excluded, particularly in eyes with significant ischaemia at baseline and after repeated intraocular anti-VEGF injections. The decision to offer prolonged anti-VEGF treatment in cases of significant coexisting macular ischaemia should not be based only on measurements of macular thickness; instead repeat fluorescein angiograms should be performed.

  9. 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.

  10. Electrophysiological changes after 360° retinotomy and macular translocation for subfoveal choroidal neovascularisation in age related macular degeneration

    PubMed Central

    Luke, C.; Aisenbrey, S.; Luke, M.; Marzella, G.; Bartz-Schmidt, K. U.; Walter, P.

    2001-01-01

    AIM—To evaluate electrophysiological changes after 360° retinotomy and macular translocation for subfoveal choroidal neovascularisation in patients with age related macular degeneration (AMD).
METHODS—A consecutive series of 32 patients suffering from subfoveal choroidal neovascularisation secondary to AMD underwent 360° retinotomy and macular translocation. The ERG served as the main parameter of the study and was recorded 1 day before the translocation surgery and no earlier than 4 weeks after the silicone oil removal.
RESULTS—The scotopic ERG amplitudes were significantly reduced after translocation surgery. Depending on the applied flash luminance the mean b-wave amplitude reduction of the scotopic ERG varied between 67% (0.2 cd.s/m2) and 74% (0.03 cd.s/m2). The a-waves and b-waves of the saturating light response decreased significantly by 46% and 59%, respectively. The photopic a-wave and b-wave amplitudes were significantly lower after the translocation surgery resulting in a mean reduction of 27% and 43%, respectively.
CONCLUSIONS—Although macular translocation may provide the potential of preserving and even restoring vision in patients with subfoveal choroidal neovascular membranes secondary to AMD the present study indicates that a significant electrophysiological decrease is caused by surgical procedures associated with this technique. Further research is necessary to clarify if certain modifications of the surgical procedure are able to substantially reduce the neuroretinal trauma.

 PMID:11466247

  11. 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

  12. Durable recovery of the macular architecture and functionality of a diagnosed age-related macular degeneration 1 year after a single intravitreal injection of dobesilate.

    PubMed

    Cuevas, P; Outeiriño, L A; Azanza, C; Giménez-Gallego, G

    2013-11-13

    Among the age-related diseases that affect vision, age-related macular degeneration is the most frequent cause of blindness in patients older than 60 years. In this communication, we report the full anatomical and functional recovery of a patient diagnosed with wet age-related macular degeneration 1 year after a single intravitreal injection of dobesilate.

  13. Durable recovery of the macular architecture and functionality of a diagnosed age-related macular degeneration 1 year after a single intravitreal injection of dobesilate

    PubMed Central

    Cuevas, P; Outeiriño, L A; Azanza, C; Giménez-Gallego, G

    2013-01-01

    Among the age-related diseases that affect vision, age-related macular degeneration is the most frequent cause of blindness in patients older than 60 years. In this communication, we report the full anatomical and functional recovery of a patient diagnosed with wet age-related macular degeneration 1 year after a single intravitreal injection of dobesilate. PMID:24225910

  14. Black Holes (With 16 figures)

    NASA Astrophysics Data System (ADS)

    Novikov, Igor

    Astrophysics of Black Holes Introduction The Origin of Stellar Black Holes A Nonrotating Black Hole Introduction Schwarzschild Gravitational Field Motion of Photons Along the Radial Direction Radial Motion of Nonrelativistic Particles The Puzzle of the Gravitational Radius R and T Regions Two Types of T-Regions Gravitational Collapse and White Holes Eternal Black Hole? Black Hole Celestial Mechanics Circular Motion Around a Black Hole Gravitational Capture of Particles by a Black Hole Corrections for Gravitational Radiation A Rotating Black Hole Introduction Gravitational Field of a Rotating Black Hole Specific Reference Frames General Properties of the Spacetime of a Rotating Black Hole; - Spacetime Inside the Horizon Celestial Mechanics of a Rotating Black Hole Motion of Particle in the Equatorial Plane Motion of Particles off the Equatorial Plane Peculiarities of the Gravitational Capture of Bodies by a Rotating - Black Hole Electromagnetic Fields Near a Black Hole Introduction Maxwell's Equations in the Neighborhood of a Rotating Black Hole Stationary Electrodynamics Boundary Conditions at the Event Horizon Electromagnetic Fields in Vacuum Magnetosphere of a Black Hole Some Aspects of Physics of Black Holes, Wormholes, and Time Machines Observational Appearence of the Black Holes in the Universe Black Holes in the Interstellar Medium Disk Accretion Black Holes in Stellar Binary Systems Black Holes in Galactic Centers Dynamical Evidence for Black Holes in Galaxy Nuclei Primordial Black Holes Acknowledgements References

  15. 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

  16. Combination of Anti-VEGF and Laser Photocoagulation for Diabetic Macular Edema: A Review

    PubMed Central

    Garcia-Arumi, Jose; Boixadera, Anna

    2017-01-01

    Diabetic macular edema (DME) is the most common cause of vision loss in diabetic patients. Thirty years ago, the Early Treatment Diabetic Retinopathy Study (ETDRS) demonstrated that focal/grid laser photocoagulation reduces moderate vision loss from DME by 50% or more; thus, macular photocoagulation became the gold standard treatment for DME. However, with the development of anti-VEGF drugs (bevacizumab, ranibizumab, and aflibercept), better outcomes were obtained in terms of visual acuity gain and decrease in macular thickness in some studies when antiangiogenic drugs were administered in monotherapy. Macular laser therapy may still play an important role as an adjuvant treatment because it is able to improve macular thickness outcomes and reduce the number of injections needed. Here, we review some of the clinical trials that have assessed the efficacy of macular laser treatment, either as part of the treatment protocol or as rescue therapy. PMID:28348882

  17. Combination of Anti-VEGF and Laser Photocoagulation for Diabetic Macular Edema: A Review.

    PubMed

    Distefano, Laura N; Garcia-Arumi, Jose; Martinez-Castillo, Vicente; Boixadera, Anna

    2017-01-01

    Diabetic macular edema (DME) is the most common cause of vision loss in diabetic patients. Thirty years ago, the Early Treatment Diabetic Retinopathy Study (ETDRS) demonstrated that focal/grid laser photocoagulation reduces moderate vision loss from DME by 50% or more; thus, macular photocoagulation became the gold standard treatment for DME. However, with the development of anti-VEGF drugs (bevacizumab, ranibizumab, and aflibercept), better outcomes were obtained in terms of visual acuity gain and decrease in macular thickness in some studies when antiangiogenic drugs were administered in monotherapy. Macular laser therapy may still play an important role as an adjuvant treatment because it is able to improve macular thickness outcomes and reduce the number of injections needed. Here, we review some of the clinical trials that have assessed the efficacy of macular laser treatment, either as part of the treatment protocol or as rescue therapy.

  18. 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.

  19. Flying Blind: Aeromedical Certification and Undiagnosed Age-Related Macular Degeneration

    DTIC Science & Technology

    2011-09-01

    Final Report Flying Blind: Aeromedical Certification and Undiagnosed Age-Related Macular Degeneration DOT/FAA/AM-11/14 Office of Aerospace Medicine...Certification and Undiagnosed Age-Related Macular Degeneration 6. Performing Organization Code 7. Author(s) 8. Performing Organization Report...resulted in an inadvertent stall.” The report also stated that “either the pilot’s macular degeneration or his unrecognized coronary artery disease

  20. Uniformly accelerated black holes

    NASA Astrophysics Data System (ADS)

    Letelier, Patricio S.; Oliveira, Samuel R.

    2001-09-01

    The static and stationary C metric are examined in a generic framework and their interpretations studied in some detail, especially those with two event horizons, one for the black hole and another for the acceleration. We find that (i) the spacetime of an accelerated static black hole is plagued by either conical singularities or a lack of smoothness and compactness of the black hole horizon, (ii) by using standard black hole thermodynamics we show that accelerated black holes have a higher Hawking temperature than Unruh temperature of the accelerated frame, and (iii) the usual upper bound on the product of the mass and acceleration parameters (<1/27) is just a coordinate artifact. The main results are extended to accelerated rotating black holes with no significant changes.

  1. 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.

  2. Supermassive Black Holes

    NASA Astrophysics Data System (ADS)

    Loeb, Abraham

    2007-04-01

    Recent data indicates that almost all galaxies possess a supermassive black hole at their center. When gas accretes onto the black hole it heats-up and shines, resulting in the appearance of a bright quasar. The earliest quasars are found to exist only a billion years after the big-bang. I will describe recent observations of both the nearest and the most distant supermassive black holes in the universe. The formation and evolution of the black hole population can be described in the context of popular models for galaxy formation. I will describe the key questions that drive current research on supermassive black holes and present theoretical work on the radiative and hydrodynamic effects that quasars have on their cosmic habitat. Within the coming decade it would be possible to test general relativity by monitoring over time, and possibly even imaging, the polarized emission from hot spots around the black hole in the center of our Galaxy (SgrA*).

  3. 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

  4. Autofluorescence Imaging for Diagnosis and Follow-up of Cystoid Macular Edema

    PubMed Central

    Ebrahimiadib, Nazanin; Riazi-Esfahani, Mohammad

    2012-01-01

    Lipofuscin results from digestion of photoreceptor outer segments by the retinal pigment epithelium (RPE) and is the principal compound that causes RPE fluorescence during autofluorescence imaging. Absorption of the 488-nanometer blue light by macular pigments, especially by the carotenoids lutein and zeaxanthin, causes normal macular hypo-autofluorescence. Fundus autofluorescence imaging is being increasingly employed in ophthalmic practice to diagnose and monitor patients with a variety of retinal disorders. In macular edema for example, areas of hyper-autofluorescence are usually present which are postulated to be due to dispersion of macular pigments by pockets of intraretinal fluid. For this reason, the masking effect of macular pigments is reduced and the natural autofluorescence of lipofuscin can be observed without interference. In cystic types of macular edema, e.g. cystoid macular edema due to retinal vein occlusion, diabetic macular edema and post cataract surgery, hyper-autofluorescent regions corresponding to cystic spaces of fluid accumulation can be identified. In addition, the amount of hyper-autofluorescence seems to correspond to the severity of edema. Hence, autofluorescence imaging, as a noninvasive technique, can provide valuable information on cystoid macular edema in terms of diagnosis, follow-up and efficacy of treatment. PMID:23264870

  5. The Nearest Black Holes

    NASA Technical Reports Server (NTRS)

    Oliversen, Ronald J. (Technical Monitor); Garcia, M.

    2003-01-01

    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. This program facilitates this study by funding related travel, computer equipment, and partial salary for a post-doc.

  6. The Nearest Black Holes

    NASA Technical Reports Server (NTRS)

    Garcia, M.; Oliversen, Ronald J. (Technical Monitor)

    2004-01-01

    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. This program facilitate this study by funding related travel, computer equipment, and partial salary for a post-doc.

  7. The Antarctic ozone hole

    NASA Astrophysics Data System (ADS)

    Molina, Mario J.

    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.

  8. Asymptotic black holes

    NASA Astrophysics Data System (ADS)

    Ho, Pei-Ming

    2017-04-01

    Following earlier works on the KMY model of black-hole formation and evaporation, we construct the metric for a matter sphere in gravitational collapse, with the back-reaction of pre-Hawking radiation taken into consideration. The mass distribution and collapsing velocity of the matter sphere are allowed to have an arbitrary radial dependence. We find that a generic gravitational collapse asymptote to a universal configuration which resembles a black hole but without horizon. This approach clarifies several misunderstandings about black-hole formation and evaporation, and provides a new model for black-hole-like objects in the universe.

  9. Evidence for black holes.

    PubMed

    Begelman, Mitchell C

    2003-06-20

    Black holes are common objects in the universe. Each galaxy contains large numbers-perhaps millions-of stellar-mass black holes, each the remnant of a massive star. In addition, nearly every galaxy contains a supermassive black hole at its center, with a mass ranging from millions to billions of solar masses. This review discusses the demographics of black holes, the ways in which they interact with their environment, factors that may regulate their formation and growth, and progress toward determining whether these objects really warp spacetime as predicted by the general theory of relativity.

  10. Oral and silent reading performance with macular degeneration.

    PubMed

    Lovie-Kitchin, J E; Bowers, A R; Woods, R L

    2000-09-01

    Previous studies have shown that reading rate for very large print (6 degrees, 1.86 logMAR character size) is a strong predictor of oral reading rate with low vision devices (LVDs). We investigated whether this would apply using large print sizes more readily available in clinical situations (e.g. 2 degrees, 1.4 logMAR), for subjects with macular degeneration. We assessed rauding rates--reading for understanding. A combination of near word visual acuity and large print reading rate (without LVDs) provided the best prediction of oral rauding rates (with LVDs). However, near word visual acuity alone was almost as good. Similarly, silent rauding rate was predicted best by near word visual acuity alone. We give near visual acuity limits as a clinical guide to expected oral and silent reading performance with LVDs for patients with macular degeneration.

  11. 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

  12. Acute lymphoblastic leukemia presenting with bilateral serous macular detachment.

    PubMed

    Vieira, Luisa; Silva, Nuno Aguiar; Medeiros, Marco Dutra; Flores, Rita; Maduro, Vitor

    2015-01-01

    Acute lymphoblastic leukemia is a malignant hematopoietic neoplasia, which is rare in adults. Although ocular fundus alterations may be commonly observed in the course of the disease, such alterations are rarely the presenting signs of the disease. Here we describe the case of a patient with painless and progressive loss of visual acuity (right eye, 2/10; left eye, 3/10) developing over two weeks, accompanied by fever and cervical lymphadenopathy. Fundus examination showed bilateral macular serous detachment, which was confirmed by optical coherence tomography. Fluorescein angiography revealed hyperfluorescent pinpoints in the posterior poles. The limits of the macular detachment were revealed in the late phase of the angiogram. The results of blood count analysis triggered a thorough, systematic patient examination. The diagnosis of acute lymphoblastic leukemia B (CD10+) was established, and intensive systemic chemotherapy was immediately initiated. One year after the diagnosis, the patient remains in complete remission without any ophthalmologic alterations.

  13. Gene Therapies for Neovascular Age-Related Macular Degeneration.

    PubMed

    Pechan, Peter; Wadsworth, Samuel; Scaria, Abraham

    2014-12-18

    Pathological neovascularization is a key component of the neovascular form (also known as the wet form) of age-related macular degeneration (AMD) and proliferative diabetic retinopathy. Several preclinical studies have shown that antiangiogenesis strategies are effective for treating neovascular AMD in animal models. Vascular endothelial growth factor (VEGF) is one of the main inducers of ocular neovascularization, and several clinical trials have shown the benefits of neutralizing VEGF in patients with neovascular AMD or diabetic macular edema. In this review, we summarize several preclinical and early-stage clinical trials with intraocular gene therapies, which have the potential to reduce or eliminate the repeated intravitreal injections that are currently required for the treatment of neovascular AMD.

  14. Wearable diagnostic system for age-related macular degeneration.

    PubMed

    Mohaghegh, N; Zadeh, E Ghafar; Magierowski, S

    2016-08-01

    This paper presents a novel head-mounted point-of-care diagnostic system for detection and continuous monitoring of Age-related Macular Degeneration (AMD). This wearable embedded open-source platform enables accurate monitoring of AMD by taking advantage of multiple standard graphical interface techniques such as Amsler Grid, Threshold Amsler Grid, Macular Computerized Psychophysical Test and Preferential Hyperacuity Perimeter (PHP). Here, we describe the proposed multi-Grid or so-called NGRID software and elaborate on the hardware prototype. This prototype includes a commercially available Oculus HMD incorporated with a single board computer. As the first step towards a fully integrated wearable system, this paper successfully proves the functionality of head-mounted graphical interface device ready for a live demonstration. Participants can experience this device and take a 10-minute AMD eye-exam. Furthermore, NGRID has been approved and permitted for an in-hospital clinical trial.

  15. Fingolimod Associated Bilateral Cystoid Macular Edema—Wait and See?

    PubMed Central

    Pul, Refik; Osmanovic, Alma; Schmalstieg, Holger; Pielen, Amelie; Pars, Kaweh; Schwenkenbecher, Philipp; Sühs, Kurt Wolfram; Yildiz, Özlem; Frank, Benedikt; Stangel, Martin; Skripuletz, Thomas

    2016-01-01

    Fingolimod 0.5-mg once-daily is an approved therapy for patients with relapsing–remitting multiple sclerosis (MS). Several pivotal and real-world studies have demonstrated that fingolimod is associated with the development of macular edema (ME). Herein, we present a case of a diabetic MS patient who developed severe bilateral ME during fingolimod treatment. By means of this case study we provide a detailed review about fingolimod associated macular edema (FAME), its current incidence with or without diabetes mellitus, and previous therapy attempts and outcomes in MS patients. Intravitreal administration of antibodies raised against vascular endothelial growth factor A (VEGF-A) has not yet been used in the management of FAME, however, the excellent therapeutic response in our patient may justify the use of anti-VEGF-A agents in combination with cessation of fingolimod to achieve fast resolution of FAME and to prevent visual deficits, particularly in bilateral FAME. PMID:27983657

  16. Compact single-channel Raman detector for macular pigments

    NASA Astrophysics Data System (ADS)

    Ermakov, Igor V.; Ermakova, Maia R.; Gellermann, Werner

    2004-07-01

    Raman detection of macular pigments (MP) holds promise as a novel noninvasive technology for the quantification of lutein and zeaxanthin carotenoids, which are thought to prevent or delay the onset of age-related macular degeneration. Using resonant excitation in the visible, we measure the Raman signals that originate from the double-bond stretch vibrations of the p-conjugated carotenoid molecule's carbon backbone. In this paper we describe the construction and performance of a new, compact, and low-cost MP Raman instrument using dielectric, angle-tuned band-pass filters for wavelength selection and single-channel photo-multiplier detection of carotenoid Raman responses. MP concentration measurements are fast and accurate, as seen in experiments with model eyes and living human eyes. The ease and rapidity of Raman MP measurements, the relative simplicity of the instrumentation, the high accuracy of the measurements, and the lack of significant systematic errors should make this technology useful for widespread clinical research.

  17. Age-Related Macular Degeneration and Intracrine Biology: An Hypothesis

    PubMed Central

    Re, Richard N.

    2016-01-01

    This laboratory has studied the intracellular actions of angiotensin II and other signaling proteins that can act in the intracellular space—peptides/proteins we have called intracrines. Moreover, we have suggested that general principles of intracrine action exist and can help explain the progression of some chronic degenerative diseases such as diabetic nephropathy and congestive heart failure. Here, a similar analysis is carried out in the case of age-related macular degeneration. We propose that intracrine mechanisms are operative in this disorder. In particular, we hypothesize that intracrine loops involving renin, angiotensin II, transforming growth factor-beta, vascular endothelial growth factor, bone morphogenetic protein-4, and p53, among other factors, are involved. If this analysis is correct, it suggests a commonality of mechanism linking chronic progressive renal diseases, congestive heart failure, and macular degeneration. PMID:27999510

  18. 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

    1999-11-03

    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.

  19. Complement pathway biomarkers and age-related macular degeneration

    PubMed Central

    Gemenetzi, M; Lotery, A J

    2016-01-01

    In the age-related macular degeneration (AMD) ‘inflammation model', local inflammation plus complement activation contributes to the pathogenesis and progression of the disease. Multiple genetic associations have now been established correlating the risk of development or progression of AMD. Stratifying patients by their AMD genetic profile may facilitate future AMD therapeutic trials resulting in meaningful clinical trial end points with smaller sample sizes and study duration. PMID:26493033

  20. Vitreomacular traction and age-related macular degeneration.

    PubMed

    Green-Simms, Amy E; Bakri, Sophie J

    2011-05-01

    The interaction between the vitreous and the internal limiting membrane of the retina is important in the pathoetiology of numerous ocular disease processes. Recent studies have focused on the vitreo-retinal interface in the context of age-related macular degeneration (AMD), linking vitreo-retinal adhesion to exudative AMD in particular. This review summarizes our knowledge of vitreous anatomy and recent investigations regarding vitreomacular adhesion and AMD.

  1. Mutations in IMPG1 cause vitelliform macular dystrophies.

    PubMed

    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

    2013-09-05

    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.

  2. Idiopathic eruptive macular pigmentation in a Chinese child

    PubMed Central

    Wei-Feng, Zha; Ai-E, Xu; Jun-Fan, Chen

    2015-01-01

    We present a case of a healthy 8-year-old boy who presented with disseminated asymptomatic brown macules on the face, neck, trunk, and proximal extremities for 3 months. Dermatologic examination revealed multiple, smooth, nonscaly, brown macules involving the face, neck, trunk, and proximal limbs. The Darier's sign was negative. Histopathologic study showed normal epidermis and basal membrane, and increasingly scattered melanophages in the papillary dermis. The final diagnosis was idiopathic eruptive macular pigmentation. PMID:26225334

  3. Smoking and age-related macular degeneration: review and update.

    PubMed

    Velilla, Sara; García-Medina, José Javier; García-Layana, Alfredo; Dolz-Marco, Rosa; 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.

  4. 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

  5. Early detection of age related macular degeneration: current status.

    PubMed

    Schwartz, Roy; Loewenstein, Anat

    2015-01-01

    Early diagnosis and treatment of choroidal neovascularization (CNV), a main cause of severe vision loss in age related macular degeneration (AMD), is crucial in order to preserve vision and the quality of life of patients. This review summarizes current literature on the subject of early detection of CNV, both in the clinic setting and mainly in the patient's home. New technologies are evolving to allow for earlier detection and thus vision preservation in AMD patients.

  6. 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

  7. 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

  8. Transfer learning based classification of optical coherence tomography images with diabetic macular edema and dry age-related macular degeneration

    PubMed Central

    Karri, S. P. K.; Chakraborty, Debjani; Chatterjee, Jyotirmoy

    2017-01-01

    We present an algorithm for identifying retinal pathologies given retinal optical coherence tomography (OCT) images. Our approach fine-tunes a pre-trained convolutional neural network (CNN), GoogLeNet, to improve its prediction capability (compared to random initialization training) and identifies salient responses during prediction to understand learned filter characteristics. We considered a data set containing subjects with diabetic macular edema, or dry age-related macular degeneration, or no pathology. The fine-tuned CNN could effectively identify pathologies in comparison to classical learning. Our algorithm aims to demonstrate that models trained on non-medical images can be fine-tuned for classifying OCT images with limited training data. PMID:28270969

  9. Age and sex distribution of some retinal macular diseases: senile and presenile macular degeneration and central serous retinitis.

    PubMed

    Knave, B; Tengroth, B; Voss, M

    1984-01-01

    The age and sex distribution of senile macular degeneration (SMD) was investigated at the Low Vision Clinic in Stockholm. SMD increased with age and was found to be more common among women than men. This difference was not due to the fact that women live longer than men or related to women consulting ophthalmologists more often than men because of visual handicap. The age and sex distribution of presenile macular degeneration ( PSMD ) and central serous retinitis (CSR) was investigated at the Department of Ophthalmology of Falun Hospital. Also PSMD increased with age and was found to be more common among women than men, even if the sex difference was not as clear as for SMD. CSR was found to be more frequent at younger ages and, contrary to SMD and PSMD , more common among men. The reasons for these sex differences in frequencies of SMD, PSMD and CSR are not known.

  10. Visual function 5 years or more after macular translocation surgery for myopic choroidal neovascularisation and age-related macular degeneration

    PubMed Central

    Takeuchi, K; Kachi, S; Iwata, E; Ishikawa, K; Terasaki, H

    2012-01-01

    Purpose To evaluate the changes in the best-corrected visual acuity (BCVA) after 1 year and after ≥5 years after macular translocation for age-related macular degeneration (AMD) or myopic choroidal neovascularisation (mCNV). Methods The medical records of 61 consecutive patients who underwent macular translocation with 360° retinotomy for AMD (35 eyes) or mCNV (26 eyes) were reviewed. Overall, 40 patients, 17 mCNV and 23 AMD, were followed for at least 5 years. BCVA and area of the Goldmann visual field (VF) measured before, 12 months after surgery, and at the final visit. Results In the 23 AMD eyes followed for ≥5 years, the mean preoperative BCVA was 1.149±0.105 logMAR units, which significantly improved to 0.69±0.06 logMAR units at 1 year (P<0.001). This BCVA was maintained at 0.633±0.083 logMAR units on their final examination. In the 17 eyes with mCNV followed for ≥5 years, the mean preoperative BCVA was 1.083±0.119 logMAR units, which was significantly improved to 0.689±0.121 logMAR units at 1 year (P=0.001). This BCVA was maintained at 0.678±0.142 logMAR units on their final examination. The area of the VF was significantly decreased at 12 months and did not change significantly thereafter. Conclusions Our results show that macular translocation surgery significantly improves the BCVA and significantly decreases the VF area of eyes with mCNV or AMD after first 1 year. The BCVA and VF area do not change significantly from the values at 1 year for at least 5 years. PMID:22173070

  11. 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…

  12. Machine learning based detection of age-related macular degeneration (AMD) and diabetic macular edema (DME) from optical coherence tomography (OCT) images.

    PubMed

    Wang, Yu; Zhang, Yaonan; Yao, Zhaomin; Zhao, Ruixue; Zhou, Fengfeng

    2016-12-01

    Non-lethal macular diseases greatly impact patients' life quality, and will cause vision loss at the late stages. Visual inspection of the optical coherence tomography (OCT) images by the experienced clinicians is the main diagnosis technique. We proposed a computer-aided diagnosis (CAD) model to discriminate age-related macular degeneration (AMD), diabetic macular edema (DME) and healthy macula. The linear configuration pattern (LCP) based features of the OCT images were screened by the Correlation-based Feature Subset (CFS) selection algorithm. And the best model based on the sequential minimal optimization (SMO) algorithm achieved 99.3% in the overall accuracy for the three classes of samples.

  13. Machine learning based detection of age-related macular degeneration (AMD) and diabetic macular edema (DME) from optical coherence tomography (OCT) images

    PubMed Central

    Wang, Yu; Zhang, Yaonan; Yao, Zhaomin; Zhao, Ruixue; Zhou, Fengfeng

    2016-01-01

    Non-lethal macular diseases greatly impact patients’ life quality, and will cause vision loss at the late stages. Visual inspection of the optical coherence tomography (OCT) images by the experienced clinicians is the main diagnosis technique. We proposed a computer-aided diagnosis (CAD) model to discriminate age-related macular degeneration (AMD), diabetic macular edema (DME) and healthy macula. The linear configuration pattern (LCP) based features of the OCT images were screened by the Correlation-based Feature Subset (CFS) selection algorithm. And the best model based on the sequential minimal optimization (SMO) algorithm achieved 99.3% in the overall accuracy for the three classes of samples. PMID:28018716

  14. Lentiviral Vector Gene Transfer of Endostatin/Angiostatin for Macular Degeneration (GEM) Study

    PubMed Central

    Campochiaro, Peter A.; Lauer, Andreas K.; Sohn, Elliott H.; Mir, Tahreem A.; Naylor, Stuart; Anderton, Matthew C.; Kelleher, Michelle; Harrop, Richard; Ellis, Scott; Mitrophanous, Kyriacos A.

    2017-01-01

    Neovascular age-related macular degeneration (NVAMD) is a prevalent cause of vision loss. Intraocular injections of VEGF-neutralizing proteins provide benefit, but many patients require frequent injections for a prolonged period. Benefits are often lost over time due to lapses in treatment. New treatments that sustain anti-angiogenic activity are needed. This study tested the safety and expression profile of a lentiviral Equine Infectious Anemia Virus (EIAV) vector expressing endostatin and angiostatin (RetinoStat®). Patients with advanced NVAMD were enrolled at three centers in the United States, and the study eye received a subretinal injection of 2.4 × 104 (n = 3), 2.4 × 105 (n = 3), or 8.0 × 105 transduction units (TU; n = 15). Each of the doses was well-tolerated with no dose-limiting toxicities. There was little or no ocular inflammation. There was one procedure-related serious adverse event (AE), a macular hole, which was managed without difficulty and resolved. There was a vector dose-related increase in aqueous humor levels of endostatin and angiostatin with high reproducibility among subjects within cohorts. Mean levels of endostatin and angiostatin peaked between 12 and 24 weeks after injection of 2.4 × 105 TU or 8.0 × 105 TU at 57–81 ng/mL for endostatin and 15–27 ng/mL for angiostatin, and remained stable through the last measurement at week 48. Long-term follow-up demonstrated expression was maintained at last measurement (2.5 years in eight subjects and >4 years in two subjects). Despite an apparent reduction in fluorescein angiographic leakage that broadly correlated with the expression levels in the majority of patients, only one subject showed convincing evidence of anti-permeability activity in these late-stage patients. There was no significant change in mean lesion size in subjects injected with 8.0 × 105 TU. These data demonstrate that EIAV vectors provide a safe platform with robust and

  15. Lentiviral Vector Gene Transfer of Endostatin/Angiostatin for Macular Degeneration (GEM) Study.

    PubMed

    Campochiaro, Peter A; Lauer, Andreas K; Sohn, Elliott H; Mir, Tahreem A; Naylor, Stuart; Anderton, Matthew C; Kelleher, Michelle; Harrop, Richard; Ellis, Scott; Mitrophanous, Kyriacos A

    2017-01-01

    Neovascular age-related macular degeneration (NVAMD) is a prevalent cause of vision loss. Intraocular injections of VEGF-neutralizing proteins provide benefit, but many patients require frequent injections for a prolonged period. Benefits are often lost over time due to lapses in treatment. New treatments that sustain anti-angiogenic activity are needed. This study tested the safety and expression profile of a lentiviral Equine Infectious Anemia Virus (EIAV) vector expressing endostatin and angiostatin (RetinoStat(®)). Patients with advanced NVAMD were enrolled at three centers in the United States, and the study eye received a subretinal injection of 2.4 × 10(4) (n = 3), 2.4 × 10(5) (n = 3), or 8.0 × 10(5) transduction units (TU; n = 15). Each of the doses was well-tolerated with no dose-limiting toxicities. There was little or no ocular inflammation. There was one procedure-related serious adverse event (AE), a macular hole, which was managed without difficulty and resolved. There was a vector dose-related increase in aqueous humor levels of endostatin and angiostatin with high reproducibility among subjects within cohorts. Mean levels of endostatin and angiostatin peaked between 12 and 24 weeks after injection of 2.4 × 10(5) TU or 8.0 × 10(5) TU at 57-81 ng/mL for endostatin and 15-27 ng/mL for angiostatin, and remained stable through the last measurement at week 48. Long-term follow-up demonstrated expression was maintained at last measurement (2.5 years in eight subjects and >4 years in two subjects). Despite an apparent reduction in fluorescein angiographic leakage that broadly correlated with the expression levels in the majority of patients, only one subject showed convincing evidence of anti-permeability activity in these late-stage patients. There was no significant change in mean lesion size in subjects injected with 8.0 × 10(5) TU. These data demonstrate that EIAV vectors provide a safe platform with robust

  16. Black Hole Simulation

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This graphic shows the computer simulation of a black hole from start to finish. Plasma is falling slowly toward the black hole in a (at the upper left). The plasma has a magnetic field, shown by the white lines. It picks up speed as it falls toward the hole in b (at the upper right), c (lower left) and d (lower right). However, the rotating black hole twists up space itself (and the magnetic field lines) and ejects electromagnetic power along the north and south poles above the black hole. The red and white color shows the immense electromagnetic power output, which eventually will pick up particles and form squirting jets. This simulation was conducted using supercomputers at Japan's National Institute for Fusion Science.

  17. Observing Black Hole Spin

    NASA Astrophysics Data System (ADS)

    Reynolds, Christopher S.

    2015-08-01

    Black hole spin is important in both the fundamental physics and astrophysics realms. In fundamental terms, many extensions and alternatives to General Relativity (GR) reveal themselves through effects related to (or at least of the same order as) spin. Astrophysically, spin is a fossil record of how black holes have grown and may, in addition, be an important source of energy (e.g., powering relativistic jets from black hole systems). I shall review recent progress on observational studies of black hole spin, especially those made in the X-ray waveband. We now have multiple techniques that can be applied in our search for black hole spin; I shall discuss the concordance (or, sometimes, lack thereof) between these techniques. Finally, I shall discuss what we can expect in the next few years with the launch of new X-ray instrumentation as well as the deployment of the Event Horizon Telescope.

  18. 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...

  19. 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...

  20. 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.

  1. Entropy of quasiblack holes

    SciTech Connect

    Lemos, Jose P. S.; Zaslavskii, Oleg B.

    2010-03-15

    We trace the origin of the black hole entropy S, replacing a black hole by a quasiblack hole. Let the boundary of a static body approach its own gravitational radius, in such a way that a quasihorizon forms. We show that if the body is thermal with the temperature taking the Hawking value at the quasihorizon limit, it follows, in the nonextremal case, from the first law of thermodynamics that the entropy approaches the Bekenstein-Hawking value S=A/4. In this setup, the key role is played by the surface stresses on the quasihorizon and one finds that the entropy comes from the quasihorizon surface. Any distribution of matter inside the surface leads to the same universal value for the entropy in the quasihorizon limit. This can be of some help in the understanding of black hole entropy. Other similarities between black holes and quasiblack holes such as the mass formulas for both objects had been found previously. We also discuss the entropy for extremal quasiblack holes, a more subtle issue.

  2. 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.

  3. Quantitative assessment of macular thickness in normal subjects and patients with diabetic retinopathy by scanning retinal thickness analyser

    PubMed Central

    Oshima, Y.; Emi, K.; Yamanishi, S.; Motokura, M.

    1999-01-01

    AIMS—To evaluate the scanning retinal thickness analyser (RTA), a novel non-invasive imaging instrument, in diagnosing and quantitatively characterising diabetic macular oedema, and to investigate the relation between central macula thickness measured by RTA and other clinical examinations.
METHODS—Central macular thickness was measured using the RTA in 40 normal subjects and 60 patients with diabetic retinopathy. The reproducibility of the retinal thickness measurements was evaluated by calculating the mean of the inter- and intrasession variations. Central macular thickness was correlated with the results of visual acuity measurements, biomicroscopy, and fluorescein angiography.
RESULTS—Intra- and intersession reproducibility of the RTA in normal subjects was plus or minus 5.2% (16 µm) and plus or minus 6.1% (19 µm), respectively. The mean central macular thickness was 182 (SD 16) µm in normal subjects, 283 (116) µm in diabetic eyes without clinically significant macular oedema (CSMO), and 564 (168) µm in diabetic eyes with CSMO. Central macular thickness was significantly greater (p<0.001) in eyes with diabetic retinopathy than in normal subjects, even when macular thickening did not meet the standard for CSMO (p=0.019) measured by biomicroscopy. Although greater fluorescein leakage at the macula results in greater central macular thickness, only eyes with diffuse leakage had statistically significant macular thickening compared with normal subjects (p=0.022). Central macular thickness measured with the RTA was significantly correlated with the logarithmic converted visual acuity (r2= 0.76) in diabetic eyes.
CONCLUSION—Scanning RTA, which has good reproducibility, might be useful to quantitatively detect and monitor macular thickening in diabetic retinopathy. Central macular thickness was highly correlated with logarithmic converted visual acuity in diabetic macular oedema.

 Keywords: scanning retinal thickness analyser; macular

  4. 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.

  5. 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)

  6. Straight hole driller

    SciTech Connect

    Samford, T.L.

    1981-08-25

    For use in a drilling string, the preferred and illustrated embodiment depicts a drill collar to be placed in the lower parts of the drill string for straightening the hole. The preferred embodiment utilizes a generally square drill collar with a thick or heavy wall. It is square in cross section along the greater portion of its length, the four corners being slightly rounded to a specified diameter on rotation, and the four lengthwise corners of the regular cross section are all reinforced with hardfacing material to a specified depth, typically tungsten carbide. The four edges abrade the bore hole as the drill string penetrates the earth. In addition, the lower end of the tubular body includes lengthwise flutes in the form known on a stabilizer to guide the hole straightening device into the hole to be reamed by operation of the device.

  7. 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.

  8. The role of epigenetics in age-related macular degeneration.

    PubMed

    Gemenetzi, M; Lotery, A J

    2014-12-01

    It is becoming increasingly evident that epigenetic mechanisms influence gene expression and can explain how interactions between genetics and the environment result in particular phenotypes during development. The extent to which this epigenetic effect contributes to phenotype heritability in age-related macular degeneration (AMD) is currently ill defined. However, emerging evidence suggests that epigenetic changes are relevant to AMD and as such provide an exciting new avenue of research for AMD. This review addresses information on the impact of posttranslational modification of the genome on the pathogenesis of AMD, such as DNA methylation changes affecting antioxidant gene expression, hypoxia-regulated alterations in chromatin structure, and histone acetylation status in relation to angiogenesis and inflammation. It also contains information on the role of non-coding RNA-mediated gene regulation in AMD at a posttranscriptional (before translation) level. Our aim was to review the epigenetic mechanisms that cause heritable changes in gene activity without changing the DNA sequence. We also describe some long-term alterations in the transcriptional potential of a cell, which are not necessarily heritable but remains to be defined in the future. Increasing understanding of the significance of common and rare genetic variants and their relationship to epigenetics and environmental influences may help in establishing methods to assess the risk of AMD. This in turn may allow new therapeutic interventions for the leading cause of central vision impairment in patients over the age of 50 years in developed countries. Search strategy We searched the MEDLINE/PubMed database following MeSH suggestions for articles including the terms: 'ocular epigenetic mechanisms', 'human disease epigenetics', and 'age-related macular degeneration genetics'. The headline used to locate related articles in PubMed was 'epigenetics in ocular disease', and to restrict search, we used the

  9. 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

  10. Intravitreal bevacizumab for persistent macular edema with proliferative diabetic retinopathy.

    PubMed

    Gulkilik, Gokhan; Taskapili, Muhittin; Kocabora, Selim; Muftuoglu, Gulipek; Demirci, Goktug

    2010-12-01

    To evaluate the effectiveness of an intravitreal bevacizumab injection on retinal neovascularization and diabetic macular edema (DME) refractory to laser photocoagulation therapy. Thirty-four eyes of 22 patients with proliferative diabetic retinopathy and DME refractory to laser photocoagulation therapy received an intravitreal injection of 1.25 mg/0.05 ml of bevazicumab. Changes in mean best-corrected visual acuity (BCVA), central macular thickness (CMT), regression of neovascularization over time, and correlation between BCVA and CMT were evaluated. Follow-up visits were at weeks 1, 2 and 4 and months 3 and 6. Mean BCVA was significantly better than baseline only at week 2 (P = 0.036). Mean CMT decreased significantly from baseline at weeks 1, 2, and 4 (P = 0.001). At months 3 and 6, mean CMT increased, albeit insignificantly (P = 0.804 and P = 1.0). The decrease in fluorescein leakage was moderate in all eyes at the end of week 1. At week 2, there was total resolution of fluorescein leakage in 24 (70.5%) eyes and moderate resolution in 10 (29.5%) eyes. At the end of month 3, the fluorescein leakage was fully resolved in 5 (14.7%) eyes, moderately resolved in 24 (70.5%) eyes, and was similar to baseline in 5 (14.7%) eyes. At month 6, the fluorescein leakage was fully resolved in 3 (8.8%) eyes, moderately resolved in 20 (58.8%) eyes, and was similar to baseline in 11 (32.4%) eyes. A moderate but insignificant negative correlation was found between visual acuity and CMT (P > 0.05). Persistence or recurrence of neovascular tissue after panretinal photocoagulation may be attributed to the production of vascular endothelial growth factor by the residual ischemic retina, which also results in persistent or recurrent DME despite macular grid photocoagulation.

  11. 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.

  12. Life Inside Black Holes

    NASA Astrophysics Data System (ADS)

    Dokuchaev, Vyacheslav

    2013-11-01

    It is considered the test planet and photon orbits of the third kind inside the black hole (BH), which are stable, periodic and neither come out the BH nor terminate at the central singularity. Interiors of the supermassive BHs may be inhabited by advanced civilizations living on the planets with the third kind orbits. In principle, one can get information from the interiors of BHs by observing their white hole counterparts.

  13. Holes in Heisenberg antiferromagnets

    NASA Astrophysics Data System (ADS)

    Chen, Yang

    1990-05-01

    In this Brief Report we show that a recent model proposed by Shankar [Phys. Rev. Lett. 63, 203 (1989)], describing the motion of holes in quantum antiferromagnets is equivalent to the Schwinger model [Phys. Rev. 128, 2425 (1962)] in 1+1 dimensions. Some exact results are deduced. In addition to the superconducting long-range order found by Shankar, it is shown that there is a 2pF hole density wave existing with the superconducting pairing instability.

  14. Age-related macular degeneration: Complement in action.

    PubMed

    van Lookeren Campagne, Menno; Strauss, Erich C; Yaspan, Brian L

    2016-06-01

    The complement system plays a key role in host-defense against common pathogens but must be tightly controlled to avoid inflammation and tissue damage. Polymorphisms in genes encoding two important negative regulators of the alternative complement pathway, complement factor H (CFH) and complement factor I (CFI), are associated with the risk for Age-Related Macular Degeneration (AMD), a leading cause of vision impairment in the ageing population. In this review, we will discuss the genetic basis of AMD and the potential impact of complement de-regulation on disease pathogenesis. Finally, we will highlight recent therapeutic approaches aimed at controlling complement activation in patients with AMD.

  15. Focal Choroidal Excavation in Best Vitelliform Macular Dystrophy: Case Report.

    PubMed

    Esfahani, Mohammad Riazi; Esfahani, Hamid Riazi; Mahmoudi, Alireza; Johari, Mohammad Karim; Hemati, Karim

    2015-05-01

    Focal choroidal excavation (FCE) was first reported as a choroidal posteriorly excavated zone without any scleral change. Choroidal excavation also divided into conforming and nonconforming type. Numerous reports demonstrated association between FCE and other disease such as choroidal neovascularization and central serous choroidoretinopathy. Here, we report a rare case of FCE in a patient with Best disease. The patient was diagnosed by spectoral domain optical coherence tomography (SD-OCT). To the best of our knowledge, our patient is the second report of choroidal excavation in Best vitelliform macular dystrophy.

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

    PubMed Central

    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

  17. Imaging geographic atrophy in age-related macular degeneration.

    PubMed

    Göbel, Arno P; Fleckenstein, Monika; Schmitz-Valckenberg, Steffen; Brinkmann, Christian K; Holz, Frank G

    2011-01-01

    Advances in retinal imaging technology have largely contributed to the understanding of the natural history, prognostic markers and disease mechanisms of geographic atrophy (GA) due to age-related macular degeneration. There is still no therapy available to halt or slow the disease process. In order to evaluate potential therapeutic effects in interventional trials, there is a need for precise quantification of the GA progression rate. Fundus autofluorescence imaging allows for accurate identification and segmentation of atrophic areas and currently represents the gold standard for evaluating progressive GA enlargement. By means of high-resolution spectral-domain optical coherence tomography, distinct microstructural alterations related to GA can be visualized.

  18. [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

  19. 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.

  20. 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.

  1. Effect of blue light-filtering intraocular lens on color vision in patients with macular diseases after vitrectomy.

    PubMed

    Mokuno, Kumiko; Asami, Tetsu; Nonobe, Norie; Ito, Hirotaka; Fujiwara, Kumi; Terasaki, Hiroko

    2016-12-01

    To evaluate the color vision of patients with macular diseases after implanting a blue light-filtering intraocular lens (IOL) during vitrectomy. Twenty-seven patients had a blue light-filtering IOL implanted during vitrectomy for macular diseases (macular disease group), and 40 patients without macular disease had the same type of IOL implanted (non-macular disease group). The postoperative best-corrected visual acuity (BCVA) was ≥ 16/20 in all patients. The Farnsworth-Munsell 100-hue test was used to determine total error scores (TES) and mean error scores under photopic and mesopic conditions in both groups. The TES under mesopic conditions was significantly higher than that under photopic conditions in both groups (P < 0.05). However, the TES in the macular disease group was not significantly different from that of the non-macular disease group under both photopic and mesopic conditions. The mean error scores under photopic conditions for hues 11, 14, 16, 17, 18, and 20 (yellowish-red to yellow) were significantly higher in the macular disease group than in the non-macular disease group. The mean error scores for hues 7 and 85 (red) were significantly higher in the non-macular disease group than in the macular disease group. Under mesopic conditions, the mean error scores for hues 30, 60, and 61 were significantly higher in the non-macular disease group than in the macular disease group (P < 0.05). Our results indicate that blue light-filtering IOLs do not alter color discrimination in eyes with macular diseases, and these patients had good postoperative BCVA even under mesopic conditions.

  2. Photographic patterns in macular images: representation by a mathematical model.

    PubMed

    Smith, R Theodore; Nagasaki, Takayuki; Sparrow, Janet R; Barbazetto, Irene; Koniarek, Jan P; Bickmann, Lee J

    2004-01-01

    Normal macular photographic patterns are geometrically described and mathematically modeled. Forty normal color fundus photographs were digitized. The green channel gray-level data were filtered and contrast enhanced, then analyzed for concentricity, convexity, and radial resolution. The foveal data for five images were fit with elliptic quadratic polynomials in two zones: a central ellipse and a surrounding annulus. The ability of the model to reconstruct the entire foveal data from selected pixel values was tested. The gray-level patterns were nested sets of concentric ellipses. Gray levels increased radially, with retinal vessels changing the patterns to star shaped in the peripheral fovea. The elliptic polynomial model could fit a high-resolution green channel foveal image with mean absolute errors of 6.1% of the gray-level range. Foveal images were reconstructed from small numbers of selected pixel values with mean errors of 7.2%. Digital analysis of normal fundus photographs shows finely resolved concentric elliptical foveal and star-shaped parafoveal patterns, which are consistent with anatomical structures. A two-zone elliptic quadratic polynomial model can approximate foveal data, and can also reconstruct it from small subsets, allowing improved macular image analysis.

  3. Macular Development in Aggressive Posterior Retinopathy of Prematurity

    PubMed Central

    Pandya, Hemang K.; Faia, Lisa J.; Robinson, Joshua; Drenser, Kimberly A.

    2015-01-01

    Purpose. To report anatomic outcomes after early and confluent laser photocoagulation of the entire avascular retina, including areas in close proximity to the fovea, in patients with APROP. We aspire to demonstrate fundoscopic evidence of transverse growth and macular development following laser treatment in APROP. Methods. Retrospective review of 6 eyes with APROP that underwent confluent laser photocoagulation of the entire avascular retina. Photographic fundoscopic imaging was performed using the RetCam to compare outcomes after treatment. Results. Mean birth weight and gestational age were 704.8 g and 24.33 weeks, respectively. There were 2 females and 1 male. The average time to laser was 9.3 weeks after birth, with the mean postmenstrual age of 34 weeks. Two eyes had zone 1 and 4 eyes had posterior zone 2 disease. Three eyes developed 4A detachments, which were successfully treated. All 6 eyes experienced transverse growth, with expansion of the posterior pole and anterior displacement of the laser treatment. Conclusion. Confluent photocoagulation of the entire avascular retina, regardless of foveal proximity, should be the mainstay for treating APROP. Examination should be conducted within 5–10 days to examine areas previously hidden by neovascularization to ensure prudent therapy. Macular development involves both transverse and anterior-posterior growth. PMID:26167498

  4. Macular Development in Aggressive Posterior Retinopathy of Prematurity.

    PubMed

    Pandya, Hemang K; Faia, Lisa J; Robinson, Joshua; Drenser, Kimberly A

    2015-01-01

    Purpose. To report anatomic outcomes after early and confluent laser photocoagulation of the entire avascular retina, including areas in close proximity to the fovea, in patients with APROP. We aspire to demonstrate fundoscopic evidence of transverse growth and macular development following laser treatment in APROP. Methods. Retrospective review of 6 eyes with APROP that underwent confluent laser photocoagulation of the entire avascular retina. Photographic fundoscopic imaging was performed using the RetCam to compare outcomes after treatment. Results. Mean birth weight and gestational age were 704.8 g and 24.33 weeks, respectively. There were 2 females and 1 male. The average time to laser was 9.3 weeks after birth, with the mean postmenstrual age of 34 weeks. Two eyes had zone 1 and 4 eyes had posterior zone 2 disease. Three eyes developed 4A detachments, which were successfully treated. All 6 eyes experienced transverse growth, with expansion of the posterior pole and anterior displacement of the laser treatment. Conclusion. Confluent photocoagulation of the entire avascular retina, regardless of foveal proximity, should be the mainstay for treating APROP. Examination should be conducted within 5-10 days to examine areas previously hidden by neovascularization to ensure prudent therapy. Macular development involves both transverse and anterior-posterior growth.

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

    PubMed Central

    Chen, Mei; Xu, Heping

    2016-01-01

    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 due to its unique anatomical and physiological 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, undergo low levels of activation (para-inflammation). In many cases, this para-inflammatory response can maintain homeostasis in the healthy aging eye. However, in patients with age-related macular degeneration (AMD), this para-inflammatory response becomes dysregulated and contributes to macular damage. Factors contributing to the dysregulation of age-related retinal para-inflammation include genetic predisposition, environmental risk factors and old age. Dysregulated para-inflammation (chronic inflammation) in AMD damages the blood retina barrier (BRB), 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 AMD, and explores the difference between beneficial para-inflammation and the detrimental chronic inflammation in the context of AMD. PMID:26292978

  6. Simple Raman Instrument for in Vivo Detection of Macular Pigments

    PubMed Central

    ERMAKOV, IGOR V.; ERMAKOVA, MAIA R.; GELLERMANN, WERNER

    2011-01-01

    Raman spectroscopy holds promise as a novel noninvasive technology for the quantification of the macular pigments (MP) lutein and zeaxanthin. These compounds, which are members of the carotenoid family, are thought to prevent or delay the onset of age-related macular degeneration, the leading cause of irreversible blindness in the elderly. It is highly likely that they achieve this protection through their function as optical filters and/or antioxidants. Using resonant excitation in the visible region, we measure and quantify the Raman signals that originate from the carbon double bond (C=C) stretch vibrations of the π-conjugated molecule backbone. In this manuscript we describe the construction and performance of a novel compact MP Raman instrument utilizing dielectric angle-tuned band-pass filters for wavelength selection and a single-channel photo-multiplier for the detection of MP Raman responses. MP concentration measurements are fast and accurate, as seen in our experiments with model eyes and living human eyes. The ease and rapidity of Raman MP measurements, the simplicity of the instrumentation, the high accuracy of the measurements, and the lack of significant systematic errors should make this technology attractive for widespread clinical research. PMID:16053555

  7. [Vision rehabilitation of patients with old-age macular degeneration].

    PubMed

    Hoyng, C B; Verezen, C A; de Jong, P T

    1998-01-24

    Age-related degeneration of the macula retinae occurs in two forms: the serious form with invasion of blood vessels and leakage, and the atrophic form. Both forms ultimately lead to a central scotoma. The prevalence of the terminal stage of age-related macular degeneration varies from 1% in the age group 65-74 years to 11% in those 85 years or over. A total of 58,500 persons in the Netherlands have age-related macular degeneration and an estimated 22,000 persons depend on visual or optic aids. Aids for close vision are good illumination, magnification (reading glasses, magnifying glasses, telescopic lenses, television reading lenses (with possibility of changing contrast), large-letter books, playing cards with large symbols) and auditory aids. Aids for distant vision reduce troublesome light (sunglasses, filter) or enlarge the image (telescopic aids). Future new aids derive from modern computer technology (personal computer, integrated braille reader and speech synthesizer) or are based on opto-electronic image processing and presentation (mini-cameras with mini-VDUs in a sort of helmet). Effective use of aids depends on attention for the patient's desires and possibilities and on counselling in handling aids. Ophthalmological checkups remain useful for the prevention and (or) treatment of accessory disorders.

  8. Laser-Induced Photic Injury Phenocopies Macular Dystrophy

    PubMed Central

    Zhang, Lijuan; Zheng, Andrew; Nie, Hongping; Bhavsar, Kavita V.; Xu, Yu; Sliney, David H.; Trokel, Stephen L.; Tsang, Stephen H

    2016-01-01

    Objective To describe the phenotypes associated with laser-induced retinal damage in children. Methods Five patients with maculopathy and reduced visual acuity associated with laser pointer use were evaluated. Best-corrected visual acuity, retinal structure, and function were monitored with color fundus, infrared (IR), and red-free images, fundus autofluorescence (AF), spectral domain-optical coherence tomography (SD-OCT), and full-field electroretinography (ERG). Results All five laser pointer injury patients had retinal lesions resembling a macular dystrophy (1 bilateral and 4 unilateral). These lesions were irregular in shape but all had a characteristic dendritic appearance with linear streaks radiating from the lesion. Photoreceptor damage was present in all patients, but serial OCT monitoring showed that subsequent photoreceptor recovery occurred over time in the eyes of at least 4 patients. 1 patient also had bilateral pigment epithelial detachments (PED). Both hyper- and hypoautofluorecence were observed in the laser damage area. Conclusions In general, OCT and IR images are quite useful to diagnose laser damage, but AF is not as sensitive. Laser pointer damage in children can occasionally be misdiagnosed as a macular dystrophy disease, but the distinctive lesions and OCT features are helpful for differentiating laser damage from other conditions. PMID:26927809

  9. Macular pigment optical density in a South Indian population.

    PubMed

    Raman, Rajiv; Rajan, Rajni; Biswas, Sayantan; Vaitheeswaran, Kulothungan; Sharma, Tarun

    2011-10-07

    PURPOSE. To estimate the normal value of macular pigment optical density (MPOD) in an adult south Indian sample. METHODS. Three hundred eyes of 161 healthy volunteers (30 men and 30 women in each of the age groups of 20-29, 30-39, 40-49, 50-59, and ≥60 years) underwent MPOD measurement with a macular densitometer. Thirty-two eyes were also checked for intersession variability. RESULTS. The mean MPODs in the Indian sample were 0.64 ± 0.23 log unit at 0.25° eccentricity, 0.50 ± 0.21 log unit at 0.5°, 0.37 ± 0.19 log unit at 1.00°, and 0.21 ± 0.16 log unit at 1.75°. At all the foveal eccentricities, the MPOD showed an increase from 20 to 29 to 30 to 39 years of age and thereby showed a decrease with age. The men aged 40 to 49 years had significantly higher MPOD than did the women (0.75 vs. 0.62 log unit, P = 0.039), and the women aged 50 to 59 years had higher MPOD than did the men (0.71 vs. 0.57 log unit, P = 0.019). There was no significant intersession or interocular variation. CONCLUSIONS. This study establishes the MPOD normogram in an adult Indian sample.

  10. CONGENITAL MACROVESSEL ASSOCIATED WITH CYSTOID MACULAR EDEMA AND AN IPSILATERAL INTRACRANIAL VENOUS MALFORMATION

    PubMed Central

    Sanfilippo, Christian J.

    2015-01-01

    Background/Purpose: To report a case of congenital retinal macrovessel associated with cystoid macular edema and an ipsilateral intracranial venous malformation. Methods: Case report. Results: A 58-year-old woman with decreased vision was found to have a congenital retinal venous macrovessel associated with cystoid macular edema because of tributary venous occlusion. The patient underwent neuroimaging and an ipsilateral venous malformation of the frontal lobe was discovered. Conclusion: Congenital retinal macrovessel can occasionally be complicated by vascular occlusion and macular edema. The authors report a case of congenital retinal macrovessel associated with an intracranial venous malformation. Clinicians should be aware of this potential association, and further studies are warranted. PMID:26421894

  11. Peripapillary subretinal neovascularization and serous macular detachment. Association with congenital optic nerve pits.

    PubMed

    Borodic, G E; Gragoudas, E S; Edward, W O; Brockhurst, R J

    1984-02-01

    Congenital anomalous disc changes were associated with acquired macular detachment and peripapillary choroidal neovascularization in two cases. The anomalous disc changes resembled optic nerve pits. In one case, the peripapillary choroidal neovascularization was treated with argon laser photocoagulation, with subsequent reattachment of the macula and considerable improvement in the visual acuity. Although the pathogenesis of macular detachment occurring with optic nerve pits is usually not disclosed by fluorescein angiography, leakage from choroidal neovascularization can occur with this congenital defect and may contribute to the formation of a neurosensory macular detachment. If found, choroidal neovascularization may represent a remedial cause for visual loss in a condition with an otherwise poor prognosis.

  12. 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.

  13. Merging Black Holes

    NASA Astrophysics Data System (ADS)

    Centrella, Joan

    2009-05-01

    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.

  14. Combination of Navigated Macular Laser Photocoagulation and Anti-VEGF Therapy: Precise Treatment for Macular Edema under Dry Retinal Conditions

    PubMed Central

    2017-01-01

    Purpose. To compare the controllability of navigated macular laser photocoagulation (MLP) in dry versus edematous retina and validate that pretreatment diagnostic images can be used as basis for navigated MLP after the macular edema (ME) has been resolved. Materials and Methods. Group 1 was divided into subgroup 1 (dry retina MLP) and subgroup 2 (MLP in ME) for comparisons of laser-burn diameters. In group 2, the areas and locations of ME before an intravitreal injection of anti-VEGF (IVAV) were compared with those of recurrent ME. Results. The average actual diameter as percentage of planned diameter of laser burn in subgroup 1 (11 DME eyes, 6 BRVO eyes) versus subgroup 2 (5 DME eyes, 8 BRVO eyes) was 115.1 ± 9.1% versus 167.2 ± 13.8% (based on retro-mode scanning laser ophthalmoscopy), and 118.1 ± 14.8% versus 176.1 ± 11.6% (based on OCT) (p < 0.001). In group 2 (6 DME eyes, 6 BRVO eyes), difference in mean ME area before IVAV and that in recurrent edema was insignificant (p > 0.05). Conclusion. The controllability of navigated MLP in dry retina is improved compared to edematous retina. This study validates that pretreatment diagnostic images can be used as basis for navigated MLP after the edema has been resolved. PMID:28316837

  15. 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

  16. Noncommutative black hole thermodynamics

    SciTech Connect

    Banerjee, Rabin; Majhi, Bibhas Ranjan; Samanta, Saurav

    2008-06-15

    We give a general derivation, for any static spherically symmetric metric, of the relation T{sub h}=(K/2{pi}) connecting the black hole temperature (T{sub h}) with the surface gravity (K), following the tunneling interpretation of Hawking radiation. This derivation is valid even beyond the semi-classical regime, i.e. when quantum effects are not negligible. The formalism is then applied to a spherically symmetric, stationary noncommutative Schwarzschild space-time. The effects of backreaction are also included. For such a black hole the Hawking temperature is computed in a closed form. A graphical analysis reveals interesting features regarding the variation of the Hawking temperature (including corrections due to noncommutativity and backreaction) with the small radius of the black hole. The entropy and tunneling rate valid for the leading order in the noncommutative parameter are calculated. We also show that the noncommutative Bekenstein-Hawking area law has the same functional form as the usual one.

  17. 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.

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. 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.

  3. Black Hole Paradoxes

    NASA Astrophysics Data System (ADS)

    Joshi, Pankaj S.; Narayan, Ramesh

    2016-10-01

    We propose here that the well-known black hole paradoxes such as the information loss and teleological nature of the event horizon are restricted to a particular idealized case, which is the homogeneous dust collapse model. In this case, the event horizon, which defines the boundary of the black hole, forms initially, and the singularity in the interior of the black hole at a later time. We show that, in contrast, gravitational collapse from physically more realistic initial conditions typically leads to the scenario in which the event horizon and space-time singularity form simultaneously. We point out that this apparently simple modification can mitigate the causality and teleological paradoxes, and also lends support to two recently suggested solutions to the information paradox, namely, the ‘firewall’ and ‘classical chaos’ proposals.

  4. 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.

  5. Superfluid Black Holes

    NASA Astrophysics Data System (ADS)

    Hennigar, Robie A.; Mann, Robert B.; Tjoa, Erickson

    2017-01-01

    We present what we believe is the first example of a "λ -line" phase transition in black hole thermodynamics. This is a line of (continuous) second order phase transitions which in the case of liquid 4He marks the onset of superfluidity. The phase transition occurs for a class of asymptotically anti-de Sitter hairy black holes in Lovelock gravity where a real scalar field is conformally coupled to gravity. We discuss the origin of this phase transition and outline the circumstances under which it (or generalizations of it) could occur.

  6. Magnonic Black Holes.

    PubMed

    Roldán-Molina, A; Nunez, Alvaro S; Duine, R A

    2017-02-10

    We show that the interaction between the spin-polarized current and the magnetization dynamics can be used to implement black-hole and white-hole horizons for magnons-the quanta of oscillations in the magnetization direction in magnets. We consider three different systems: easy-plane ferromagnetic metals, isotropic antiferromagnetic metals, and easy-plane magnetic insulators. Based on available experimental data, we estimate that the Hawking temperature can be as large as 1 K. We comment on the implications of magnonic horizons for spin-wave scattering and transport experiments, and for magnon entanglement.

  7. Superfluid Black Holes.

    PubMed

    Hennigar, Robie A; Mann, Robert B; Tjoa, Erickson

    2017-01-13

    We present what we believe is the first example of a "λ-line" phase transition in black hole thermodynamics. This is a line of (continuous) second order phase transitions which in the case of liquid ^{4}He marks the onset of superfluidity. The phase transition occurs for a class of asymptotically anti-de Sitter hairy black holes in Lovelock gravity where a real scalar field is conformally coupled to gravity. We discuss the origin of this phase transition and outline the circumstances under which it (or generalizations of it) could occur.

  8. 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.

  9. 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.

  10. 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.

  11. Magnonic Black Holes

    NASA Astrophysics Data System (ADS)

    Roldán-Molina, A.; Nunez, Alvaro S.; Duine, R. A.

    2017-02-01

    We show that the interaction between the spin-polarized current and the magnetization dynamics can be used to implement black-hole and white-hole horizons for magnons—the quanta of oscillations in the magnetization direction in magnets. We consider three different systems: easy-plane ferromagnetic metals, isotropic antiferromagnetic metals, and easy-plane magnetic insulators. Based on available experimental data, we estimate that the Hawking temperature can be as large as 1 K. We comment on the implications of magnonic horizons for spin-wave scattering and transport experiments, and for magnon entanglement.

  12. The role of epigenetics in age-related macular degeneration

    PubMed Central

    Gemenetzi, M; Lotery, A J

    2014-01-01

    It is becoming increasingly evident that epigenetic mechanisms influence gene expression and can explain how interactions between genetics and the environment result in particular phenotypes during development. The extent to which this epigenetic effect contributes to phenotype heritability in age-related macular degeneration (AMD) is currently ill defined. However, emerging evidence suggests that epigenetic changes are relevant to AMD and as such provide an exciting new avenue of research for AMD. This review addresses information on the impact of posttranslational modification of the genome on the pathogenesis of AMD, such as DNA methylation changes affecting antioxidant gene expression, hypoxia-regulated alterations in chromatin structure, and histone acetylation status in relation to angiogenesis and inflammation. It also contains information on the role of non-coding RNA-mediated gene regulation in AMD at a posttranscriptional (before translation) level. Our aim was to review the epigenetic mechanisms that cause heritable changes in gene activity without changing the DNA sequence. We also describe some long-term alterations in the transcriptional potential of a cell, which are not necessarily heritable but remains to be defined in the future. Increasing understanding of the significance of common and rare genetic variants and their relationship to epigenetics and environmental influences may help in establishing methods to assess the risk of AMD. This in turn may allow new therapeutic interventions for the leading cause of central vision impairment in patients over the age of 50 years in developed countries. Search strategy We searched the MEDLINE/PubMed database following MeSH suggestions for articles including the terms: ‘ocular epigenetic mechanisms', ‘human disease epigenetics', and ‘age-related macular degeneration genetics'. The headline used to locate related articles in PubMed was ‘epigenetics in ocular disease', and to restrict search, we used

  13. Electron hole tracking PIC simulation

    NASA Astrophysics Data System (ADS)

    Zhou, Chuteng; Hutchinson, Ian

    2016-10-01

    An electron hole is a coherent BGK mode solitary wave. Electron holes are observed to travel at high velocities relative to bulk plasmas. The kinematics of a 1-D electron hole is studied using a novel Particle-In-Cell simulation code with fully kinetic ions. A hole tracking technique enables us to follow the trajectory of a fast-moving solitary hole and study quantitatively hole acceleration and coupling to ions. The electron hole signal is detected and the simulation domain moves by a carefully designed feedback control law to follow its propagation. This approach has the advantage that the length of the simulation domain can be significantly reduced to several times the hole width, which makes high resolution simulations tractable. We observe a transient at the initial stage of hole formation when the hole accelerates to several times the cold-ion sound speed. Artificially imposing slow ion speed changes on a fully formed hole causes its velocity to change even when the ion stream speed in the hole frame greatly exceeds the ion thermal speed, so there are no reflected ions. The behavior that we observe in numerical simulations agrees very well with our analytic theory of hole momentum conservation and energization effects we call ``jetting''. The work was partially supported by the NSF/DOE Basic Plasma Science Partnership under Grant DE-SC0010491. Computer simulations were carried out on the MIT PSFC parallel AMD Opteron/Infiniband cluster Loki.

  14. Towards a model to predict macular dichromats' naming errors: effects of CIE saturation and dichromatism type.

    PubMed

    Lillo, J; Vitini, I; Caballero, A; Moreira, H

    2001-05-01

    Thirty macular dichromat children (12 protanopes + 18 deuteranopes) and 29 controls, between 5 and 9 years old, participated in a monolexemic denomination task. Their clinical status was determined after a repeated application of a chromatic test set (Ishihara, CUCVT, and TIDA). The stimuli to be named were 12 tiles from the Color-Aid set belonging to the green, blue, and purple basic categories. Results showed that: (a) Dichromats made more naming errors when low saturation stimuli were used; (b) protanopes made more errors that deuteranopes; and (c) pseudoisochromatic lines predicted accurately the type of most frequent naming errors but they underestimated macular dichromats' functional capacity to name colors. Results are consistent with a model of macular dichromats' vision that hypothesizes a residual third type of cone in the periphery of the retina. Implications of this fact for everyday use of colors by macular dichromats' and for the validity of standard clinical diagnoses are discussed.

  15. 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 ...

  16. Evolving techniques in the treatment of macular detachment caused by optic nerve pits.

    PubMed

    Cox, M S; Witherspoon, C D; Morris, R E; Flynn, H W

    1988-07-01

    Fourteen patients with macular detachments caused by optic nerve pits were treated for progressive visual loss, cystoid macular changes, or atrophy of the macular retinal pigment epithelium. Photocoagulation of the temporal disc border alone was unsuccessful in two cases but promptly reattached the macula of two patients immobilized after laser surgery. Vitrectomy and gas tamponade improved vision and flattened the macula of three patients over various periods. The detachment recurred in one patient. Prompt and sustained macular reattachment with improved vision was noted after photocoagulation, vitrectomy, and gas tamponade in eight patients, although four required second operations. The prompt reattachment and visual recovery noted in these eight patients surpasses the reported 25% rate of spontaneous resolution.

  17. New approaches and potential treatments for dry age-related macular degeneration.

    PubMed

    Damico, Francisco Max; Gasparin, Fabio; Scolari, Mariana Ramos; Pedral, Lycia Sampaio; Takahashi, Beatriz Sayuri

    2012-01-01

    Emerging treatments for dry age-related macular degeneration (AMD) and geographic atrophy focus on two strategies that target components involved in physiopathological pathways: prevention of photoreceptors and retinal pigment epithelium loss (neuroprotection induction, oxidative damage prevention, and visual cycle modification) and suppression of inflammation. Neuroprotective drugs, such as ciliary neurotrophic factor, brimonidine tartrate, tandospirone, and anti-amyloid β antibodies, aim to prevent apoptosis of retinal cells. Oxidative stress and depletion of essential micronutrients are targeted by the Age-Related Eye Disease Study (AREDS) formulation. Visual cycle modulators reduce the activity of the photoreceptors and retinal accumulation of toxic fluorophores and lipofuscin. Eyes with dry age-related macular degeneration present chronic inflammation and potential treatments include corticosteroid and complement inhibition. We review the current concepts and rationale of dry age-related macular degeneration treatment that will most likely include a combination of drugs targeting different pathways involved in the development and progression of age-related macular degeneration.

  18. 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

  19. 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.

  20. Evaluation of an oral telomerase activator for early age-related macular degeneration - a pilot study

    PubMed Central

    Dow, Coad Thomas; Harley, Calvin B

    2016-01-01

    Purpose Telomere attrition and corresponding cellular senescence of the retinal pigment epithelium contribute to the changes of age-related macular degeneration. Activation of the enzyme telomerase can add telomeric DNA to retinal pigment epithelium chromosomal ends and has been proposed as a treatment for age-related macular degeneration. We report the use of a small molecule, oral telomerase activator (TA)-65 in early macular degeneration. This study, focusing on early macular degeneration, provides a model for the use of TAs in age-related disease. Method Thirty-eight (38) patients were randomly assigned to a 1-year, double-blinded, placebo-controlled interventional study with arms for oral TA-65 or placebo. Macular functions via micro-perimetry were the primary measured outcomes. Results The macular function in the arm receiving the TA-65 showed significant improvement relative to the placebo control. The improvement was manifest at 6 months and was maintained at 1 year: macular threshold sensitivity (measured as average dB [logarithmic decibel scale of light attenuation]) improved 0.97 dB compared to placebo (P-value 0.02) and percent reduced thresholds lessened 8.2% compared to the placebo arm (P-value 0.04). Conclusion The oral TA significantly improved the macular function of treatment subjects compared to controls. Although this study was a pilot and a larger study is being planned, it is noteworthy in that it is, to our knowledge, the first randomized placebo-controlled study of a TA supplement. PMID:26869760

  1. Serous Macular Detachment Secondary to Optic Pit: Surgical Treatment and Long Time Results

    PubMed Central

    Cevher, Selim; Sahinoglu-Keskek, Nedime; Unal, Fikret; Demirduzen, Selahaddin; Oksuz, Huseyin

    2016-01-01

    32-year-old Turkish male patient presented with an optic disk pit and serous macular detachment in the left eye. Spectral domain optical coherence tomography revealed serous macular detachment and retinoschisis. After vitrectomy the retina gradually flattened and vision was gradually improved. We aimed to report a case of serous macula detachment secondary to optic pit and long term result of surgical treatment. PMID:26881159

  2. 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.

  3. 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.

  4. Measuring Small Leak Holes

    NASA Technical Reports Server (NTRS)

    Koch, D. E.; Stephenson, J. G.

    1983-01-01

    Hole sizes deduced from pressure measurements. Measuring apparatus consists of pitot tube attached to water-filled manometer. Compartment tested is pressurized with air. Pitot probe placed at known distance from leak. Dynamic pressure of jet measured at that point and static pressure measured in compartment. Useful in situations in which small leaks are tolerable but large leaks are not.

  5. 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)

  6. Rotating black hole hair

    NASA Astrophysics Data System (ADS)

    Gregory, Ruth; Kubizňák, David; Wills, Danielle

    2013-06-01

    A Kerr black hole sporting cosmic string hair is studied in the context of the abelian Higgs model vortex. It is shown that such a system displays much richer phenomenology than its static Schwarzschild or Reissner-Nordstrom cousins, for example, the rotation generates a near horizon `electric' field. In the case of an extremal rotating black hole, two phases of the Higgs hair are possible: large black holes exhibit standard hair, with the vortex piercing the event horizon. Small black holes on the other hand, exhibit a flux-expelled solution, with the gauge and scalar field remaining identically in their false vacuum state on the event horizon. This solution however is extremely sensitive to confirm numerically, and we conjecture that it is unstable due to a supperradiant mechanism similar to the Kerr-adS instability. Finally, we compute the gravitational back reaction of the vortex, which turns out to be far more nuanced than a simple conical deficit. While the string produces a conical effect, it is conical with respect to a local co-rotating frame, not with respect to the static frame at infinity.

  7. Laser bottom hole assembly

    SciTech Connect

    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.

  8. Octonionic black holes

    NASA Astrophysics Data System (ADS)

    Bossard, Guillaume

    2012-05-01

    Using algebraic tools inspired by the study of nilpotent orbits in simple Lie algebras, we obtain a large class of solutions describing interacting non-BPS black holes in {N} = 8 supergravity, which depend on 44 harmonic functions. For this purpose, we consider a truncation {E_{{{6}({6})}}}/S{p_{{c}}}( {8,{R}} ) subset {E_{{{8}({8})}}}/{{Spin}}_{{c}}^{ * }( {16} ) of the non-linear sigma model describing stationary solutions of the theory, which permits a reduction of algebraic computations to the multiplication of 27 by 27 matrices. The lift to {N} = 8 supergravity is then carried out without loss of information by using a pertinent representation of the moduli parametrizing E7(7)/SUc (8) in terms of complex valued Hermitian matrices over the split octonions, which generalise the projective coordinates of exceptional special K¨ahler manifolds. We extract the electromagnetic charges, mass and angular momenta of the solutions, and exhibit the duality invariance of the black holes distance separations. We discuss in particular a new type of interaction which appears when interacting non-BPS black holes are not aligned. Finally we will explain the possible generalisations toward the description of the most general stationary black hole solutions of {N} = 8 supergravity.

  9. 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…

  10. 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.

  11. The genetics of age-related macular degeneration.

    PubMed

    Guymer, Robyn

    2001-07-01

    AIM: To review the genetics of age-related macular degeneration (AMD). The pathogenesis of AMD, the leading cause of severe visual disability and blindness in our community, remains unknown. However, AMD is regarded as a genetic disease where family history of AMD is a significant risk factor for the disease. Understanding the genetic factors associated with AMD offers the greatest chance for understanding the underlying disease processes. METHODS: Through a review of the literature and the use of original research findings, the current knowledge of the genetics of AMD is explored. CONCLUSION: AMD is increasing in prevalence and remains a major challenge for eye heath providers. Finding the genes that are associated with AMD offers the greatest chance for the development of preventative strategies and treatments.

  12. Mechanisms of age-related macular degeneration and therapeutic opportunities.

    PubMed

    van Lookeren Campagne, Menno; LeCouter, Jennifer; Yaspan, Brian L; Ye, Weilan

    2014-01-01

    As the age of the population increases in many nations, age-related degenerative diseases pose significant socioeconomic challenges. One of the key degenerative diseases that compromise quality of life is age-related macular degeneration (AMD). AMD is a multi-faceted condition that affects the central retina, which ultimately leads to blindness in millions of people worldwide. The pathophysiology and risk factors for AMD are complex, and the symptoms manifest in multiple related but distinct forms. The ability to develop effective treatments for AMD will depend on a thorough understanding of the underlying pathophysiology, risk factors, and driver molecular pathways, as well as the ability to develop useful animal models. This review provides an overview of the aforementioned aspects in AMD.

  13. Acute macular neuroretinopathy associated with systemic lupus erythematosus.

    PubMed

    Lee, D H; Lee, S C; Kim, M

    2016-04-01

    Acute macular neuroretinopathy (AMN) is a rare disorder that presents with abrupt visual change with wedge-shaped or flower-like lesions pointing towards the fovea. Ischemic insults to the retinal capillary plexus may be important for development of this disease. While many case reports have been published on AMN, none have described AMN in association with systemic lupus erythematosus (SLE). Here, we report a case of AMN associated with newly-diagnosed SLE. We speculate that in patients with lupus flares, immune complex-mediated vascular injury and microvascular thrombosis may disrupt the deep retinal capillary network, causing ischemic damages to the outer retina and leading to the development of AMN. AMN can develop in patients with lupus flares, and must be considered as an SLE-associated ophthalmologic complication. To the best of our knowledge, this is the first case report of AMN associated with SLE.

  14. ‘Toy' laser macular burns in children

    PubMed Central

    Raoof, N; Chan, T K J; Rogers, N K; Abdullah, W; Haq, I; Kelly, S P; Quhill, F M

    2014-01-01

    Purpose Laser ‘toys' can be purchased online and imported with relative ease; the variety of such devices is a potential public safety concern. We describe five children with maculopathy following exposure to laser ‘toys'. Methods Case series of maculopathy following exposure to laser ‘toys'. Results Five children were seen in our Ophthalmic Unit with macular injuries following exposure to laser ‘toys'. Clinically, three children had an acute vitelliform-like maculopathy which resolved to leave sub-foveal retinal pigment epithelium changes with reduced vision. One case was complicated by a choroidal neovascular membrane. Conclusion Laser ‘toys', which resemble laser pointers, are increasingly available over the internet. Such ‘toys' may not meet safety standards. Retinal injury in childhood following exposure to laser ‘toys' is a public safety concern. PMID:24434663

  15. Light and macular degeneration: a biophysical and clinical perspective.

    PubMed

    Mainster, M A

    1987-01-01

    The evidence linking photic retinopathy to ageing macular degeneration (AMD) is compelling but circumstantial. The biophysical foundations of ageing theory are presented, in addition to an analysis of retinal senescence and the potential contributory role of photochemical retinal damage. Although there is pressure to implement clinical therapy for AMD based on laboratory studies of photic retinopathy, there is no evidence at this time that any such therapy is effective. Nonetheless, until the relationship between photic retinopathy and AMD is better understood, it is appropriate for individuals to use ultraviolet and deep blue protective sunglasses in bright environments, particularly if they have reduced ocular pigmentation or if they are aphakes or pseudophakes without an ultraviolet-protective intraocular lens.

  16. 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.

  17. [Molecular genetic basis of age-related macular degeneration].

    PubMed

    Boĭko, É V; Churashov, S V; Kamilova, T A

    2013-01-01

    Visual loss due to age-related macular degeneration (AMD) is caused by one or both forms of advanced disease: "wet" (neovascular) or "dry" (geographic atrophy). Immune system plays a central role in pathogenesis and progression of both AMD forms. Main genetic polymorphisms associated with risk of AMD development and progression were found to be genes that regulate inflammation especially in complement factor H gen (1q31 locus) and 10q26 locus (PLEKHAI/ARMS2/HTRA1). Association of response to treatment and genotype was shown in patients with AMD. Complete characterization of both common and rare alleles that influence AMD risk is necessary for accurate determination of individual genetic risk as well as identification of new targets for therapeutic intervention.

  18. Highly penetrant alleles in age-related macular degeneration.

    PubMed

    den Hollander, Anneke I; de Jong, Eiko K

    2014-11-06

    Age-related macular degeneration (AMD) is a complex disease caused by a combination of genetic and environmental factors. Genome-wide association studies have identified several common genetic variants associated with AMD, which together account for 15%-65% of the heritability of AMD. Multiple hypotheses to clarify the unexplained portion of genetic variance have been proposed, such as gene-gene interactions, gene-environment interactions, structural variations, epigenetics, and rare variants. Several studies support a role for rare variants with large effect sizes in the pathogenesis of AMD. In this work, we review the methods that can be used to detect rare variants in common diseases, as well as the recent progress that has been made in the identification of rare variants in AMD. In addition, the relevance of these rare variants for diagnosis, prognosis, and treatment of AMD is highlighted.

  19. 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.

  20. 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

  1. [Management of age-related macular degeneration. An update].

    PubMed

    García Lozano, Isabel; López García, Santiago; Elosua de Juán, Isabel

    2012-01-01

    Age-related macular degeneration is the leading cause of legal blindness in people over 50 in developed countries. It is a multifactorial disease resulting from the interaction of genetic and environmental factors, and the age is the only worldwide admitted risk factor. The socioeconomic impact of the disease reaches enormous proportions, if we take into account the high cost of the available antiangiogenic therapy, the strict schedule of medical visits that it requires, and the impairment that it gives rise to. The response to treatment and the visual outcomes improve with early management of the retinal lesions, thus the early diagnosis of the disease in its initial phases, based on self-control with an Amsler grid and with regular ophthalmologic assessments, is essential.

  2. Update on geographic atrophy in age-related macular degeneration.

    PubMed

    Biarnés, Marc; Monés, Jordi; Alonso, Jordi; Arias, Luis

    2011-07-01

    Age-related macular degeneration (AMD) is the main cause of legal blindness in older patients in developed countries, and geographic atrophy (GA) represents the advanced form of dry AMD. Although it accounts for one third of the cases of late AMD and is responsible for 20% of the cases of severe visual loss due to the disorder. GA currently lacks effective treatment, whereas antiangiogenic therapies have been shown to be successful in managing choroidal neovascularization, the other form of late AMD. Recent advances in GA epidemiology, etiology, genetics, and imaging techniques have renewed the interest in this entity, which is a cause of progressive visual loss even in treated patients with neovascular AMD. This knowledge has triggered many clinical trials targeting different molecules shown to be associated with the disease, and it is hoped that this research will translate into effective drugs for GA in the near future.

  3. Evidence-Based Treatment of Diabetic Macular Edema.

    PubMed

    Barham, Rasha; El Rami, Hala; Sun, Jennifer K; Silva, Paolo S

    2017-01-01

    Diabetes mellitus is a chronic disease that affects 415 million people worldwide. Despite treatment advances, diabetic eye disease remains a leading cause of vision loss worldwide. Diabetic macular edema (DME) is a common cause of vision loss in diabetic patients. The pathophysiology is complex and involves multiple pathways that ultimately lead to central retinal thickening and, if untreated, visual loss. First-line treatment of DME has evolved from focal/grid laser established by the Early Treatment of Diabetic Retinopathy Study (ETDRS) to intravitreous pharmacologic therapy. Landmark prospective clinical trials examining the effect of intravitreous injections of vascular endothelial growth factor (VEGF) inhibitors in the treatment of DME have demonstrated improved visual outcomes over focal grid laser. This review focuses on the scientific evidence treatment of DME, disease pathophysiology, clinical disease course, current treatment standards, and emerging novel therapeutic approaches.

  4. 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

  5. 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.

  6. 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.

  7. Highly Penetrant Alleles in Age-Related Macular Degeneration

    PubMed Central

    den Hollander, Anneke I.; de Jong, Eiko K.

    2015-01-01

    Age-related macular degeneration (AMD) is a complex disease caused by a combination of genetic and environmental factors. Genome-wide association studies have identified several common genetic variants associated with AMD, which together account for 15%–65% of the heritability of AMD. Multiple hypotheses to clarify the unexplained portion of genetic variance have been proposed, such as gene–gene interactions, gene–environment interactions, structural variations, epigenetics, and rare variants. Several studies support a role for rare variants with large effect sizes in the pathogenesis of AMD. In this work, we review the methods that can be used to detect rare variants in common diseases, as well as the recent progress that has been made in the identification of rare variants in AMD. In addition, the relevance of these rare variants for diagnosis, prognosis, and treatment of AMD is highlighted. PMID:25377141

  8. Lipids, Lipoproteins, and Age-Related Macular Degeneration

    PubMed Central

    Ebrahimi, Katayoon B.; Handa, James T.

    2011-01-01

    Age-related macular degeneration (AMD) is the leading cause of blindness among the elderly. While excellent treatment has emerged for neovascular disease, treatment for early AMD is lacking due to an incomplete understanding of the early molecular events. A prominent age-related change is the accumulation of neutral lipid in normal Bruch's membrane (BrM) throughout adulthood and also disease-related BrM accumulations called basal deposits and drusen. AMD lesion formation has thus been conceptualized as sharing mechanisms with atherosclerotic plaque formation, where low-density lipoprotein (LDL) retention within the arterial wall initiates a cascade of pathologic events. However, we do not yet understand how lipoproteins contribute to AMD. This paper explores how systemic and local production of lipoproteins might contribute to the pathogenesis of AMD. PMID:21822496

  9. [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.

  10. Macular laser photocoagulation with or without intravitreal triamcinolone pretreatment for diabetic macular edema: a result from five randomized controlled trials

    PubMed Central

    Liu, Xiang-Dong; Zhou, Xiao-Dong; Wang, Zhi; Shen, Yong-Ming

    2016-01-01

    AIM To assess possible benefits of intravitreal triamcinolone acetonide (IVTA) injection as pretreatment for macular laser photocoagulation (MLP) in patients with diabetic macular edema (DME). METHODS Published randomized controlled trials (RCTs) concerning MLP with or without IVTA pretreatment for DME were retrieved from databases CNKI, Medline, EMbase, Web of Science, and the Cochrane Library. A Meta-analysis on eligible studies was conducted using RevMan 5.0 software. Two investigators independently assessed the quality of the trials and extracted data. Main outcome measures included the change in best corrected visual acuity (BCVA), difference in central macular thickness (CMT) and adverse events reporting in particular elevated intraocular pressure within the follow-up period. The results were pooled using weight mean difference (WMD) or odds risk (OR) with their corresponding 95% confidence intervals (CI). A fixed- or random-effect model was employed depending on the heterogeneity of the inclusion trials. RESULTS Finally, five independent RCTs were identified and used for comparing MLP with IVTA pretreatment (131 eyes) with MLP alone (133 eyes, control group). The overall study quality was relatively higher according to the modified Jadad scale. The Meta-analysis showed that MLP with IVTA pretreatment significantly reduced CMT at one, three and six months (P=0.002, 0.0003 and 0.04, respectively), compared with MLP alone. The IVTA pretreatment group showed statistically significant improvements in BCVA at the one-month follow up as compared with the control group (P=0.03). At three- and six-month follow up, there was a beneficial trend towards improving visual acuity in the IVTA pretreatment group without statistical significance between groups (P=0.06 and 0.20, respectively). The incidence of elevation of intraocular pressure was significantly higher in the IVTA pretreatment group than in the control group (P<0.0001). No evidence of publication bias was

  11. Towards noncommutative quantum black holes

    SciTech Connect

    Lopez-Dominguez, J. C.; Obregon, O.; Sabido, M.; Ramirez, C.

    2006-10-15

    In this paper we study noncommutative black holes. We use a diffeomorphism between the Schwarzschild black hole and the Kantowski-Sachs cosmological model, which is generalized to noncommutative minisuperspace. Through the use of the Feynman-Hibbs procedure we are able to study the thermodynamics of the black hole, in particular, we calculate the Hawking's temperature and entropy for the noncommutative Schwarzschild black hole.

  12. 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).

  13. Adaptive Optics Reveals Photoreceptor Abnormalities in Diabetic Macular Ischemia

    PubMed Central

    Nesper, Peter L.; Scarinci, Fabio

    2017-01-01

    Diabetic macular ischemia (DMI) is a phenotype of diabetic retinopathy (DR) associated with chronic hypoxia of retinal tissue. The goal of this prospective observational study was to report evidence of photoreceptor abnormalities using adaptive optics scanning laser ophthalmoscopy (AOSLO) in eyes with DR in the setting of deep capillary plexus (DCP) non-perfusion. Eleven eyes from 11 patients (6 women, age 31–68), diagnosed with DR without macular edema, underwent optical coherence tomography angiography (OCTA) and AOSLO imaging. One patient without OCTA imaging underwent fluorescein angiography to characterize the enlargement of the foveal avascular zone. The parameters studied included photoreceptor heterogeneity packing index (HPi) on AOSLO, as well as DCP non-perfusion and vessel density on OCTA. Using AOSLO, OCTA and spectral domain (SD)-OCT, we observed that photoreceptor abnormalities on AOSLO and SD-OCT were found in eyes with non-perfusion of the DCP on OCTA. All eight eyes with DCP non-flow on OCTA showed photoreceptor abnormalities on AOSLO. Six of the eight eyes also had outer retinal abnormalities on SD-OCT. Three eyes with DR and robust capillary perfusion of the DCP had normal photoreceptors on SD-OCT and AOSLO. Compared to eyes with DR without DCP non-flow, the eight eyes with DCP non-flow had significantly lower HPi (P = 0.013) and parafoveal DCP vessel density (P = 0.016). We found a significant correlation between cone HPi and parafoveal DCP vessel density (r = 0.681, P = 0.030). Using a novel approach with AOSLO and OCTA, this study shows an association between capillary non-perfusion of the DCP and abnormalities in the photoreceptor layer in eyes with DR. This observation is important in confirming the significant contribution of the DCP to oxygen requirements of photoreceptors in DMI, while highlighting the ability of AOSLO to detect subtle photoreceptor changes not always visible on SD-OCT. PMID:28068435

  14. 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

  15. The clinical utility of aflibercept for diabetic macular edema.

    PubMed

    Stewart, Michael W

    2015-01-01

    The treatment of center-involving diabetic macular edema (DME) has improved because of the proven efficacy of drugs that inhibit the effects of vascular endothelial growth factor (VEGF). The newest anti-VEGF drug, aflibercept, has recently been approved by the United States Food and Drug Administration for the treatment of center-involving DME and for diabetic retinopathy in eyes with DME. In the pivotal Phase III VISTA and VIVID trials, intravitreal aflibercept 2 mg injections every 4 or 8 weeks (after 5 monthly loading doses) produced superior gains in BCVA compared to laser/sham injections. In the Diabetic Retinopathy Clinical Research Network Protocol T trial, which featured monthly anti-VEGF monotherapy for 6 months, followed by monthly pro re nata anti-VEGF injections with laser rescue therapy from months 6 through 12, aflibercept 2 mg monthly was superior to bevacizumab 1.25 mg and ranibizumab 0.5 mg in eyes with BCVA of 20/50 or worse (aflibercept versus bevacizumab: P<0.001; aflibercept versus ranibizumab: P=0.003), but the three regimens were comparable for eyes with VA of 20/40 or better. Only in the 20/50 or worse subgroup did aflibercept achieve clinical superiority (>5 letter difference) to bevacizumab. Each treatment regimen led to significant macular thinning, with aflibercept being superior to bevacizumab in both visual acuity subgroups (P<0.001 for each), but it was not statistically superior to ranibizumab in either group. In diabetic patients, aflibercept has an excellent safety profile that does not appear to differ from laser/sham or other VEGF inhibitory drugs.

  16. 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.

  17. Light distributions on the retina: relevance to macular pigment photoprotection.

    PubMed

    Bone, Richard A; Gibert, Jorge C; Mukherjee, Anirbaan

    2012-01-01

    Light exposure has been implicated in age-related macular degeneration (AMD). This study was designed to measure cumulative light distribution on the retina to determine whether it peaked in the macula. An eye-tracker recorded the subject's field of view and pupil size, and superimposed the gaze position. Fifteen naïve subjects formed a test group; 5 formed a control group. In phase 1, all subjects viewed a sequence of photographic images. In phase 2, the naïve subjects observed a video; in phase 3, they performed computer tasks; in phase 4, the subjects walked around freely. In phase 1, control subjects were instructed to gaze at bright features in the field of view and, in a second test, at dark features. Test group subjects were allowed to gaze freely for all phases. Using the subject's gaze coordinates, we calculated the cumulative light distribution on the retina. As expected for control subjects, cumulative retinal light distributions peaked and dipped in the fovea when they gazed at bright or dark features respectively in the field of view. The light distribution maps obtained from the test group showed a consistent tendency to peak in the macula in phase 3, a variable tendency in phase 4, but little tendency in phases 1 and 2. We conclude that a tendency for light to peak in the macula is a characteristic of some individuals and of certain tasks. In these situations, risk of AMD could be increased but, at the same time, mitigated by the presence of macular carotenoids.

  18. Interactive Retinal Blood Flow Analysis of the Macular Region

    PubMed Central

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

    2015-01-01

    The study of retinal hemodynamics plays an important role to understand the onset and progression of diabetic retinopathy which is a leading cause of blindness in American adults. 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-3005, Optical Imaging, Rehovot, Israel). By employing a high definition stroboscopic fundus camera, the RFI device is able to assess retinal blood flow characteristics in vivo even in the capillaries. 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 as well as BFR in the macular region. Optical coherence tomography (OCT) data from commercially available devices were 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) which other currently available devices targeting the retinal microcirculation are not yet capable of. 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 were 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% in the RFI built-in software to 15.9% in our proposed method (p<0.001). PMID:26569349

  19. Ensuring Fully Soldered Through Holes

    NASA Technical Reports Server (NTRS)

    Blow, Raymond K.

    1987-01-01

    Simple differential-pressure soldering method provides visual evidence that hidden joints are fully soldered. Intended for soldering connector pins in plated through holes in circuit boards. Molten solder flows into plated through holes, drawn by vacuum in manifold over circuit board. Differential-pressure process ensures solder wets entire through hole around connector pin.

  20. The Value of Measurement of Macular Carotenoid Pigment Optical Densities and Distributions in Age-Related Macular Degeneration and Other Retinal Disorders

    PubMed Central

    Bernstein, Paul S.; Delori, François C.; Richer, Stuart; van Kuijk, Frederik J. M.; Wenzel, Adam J.

    2009-01-01

    There is increasing recognition that the optical and antioxidant properties of the xanthophyll carotenoids lutein and zeaxanthin play an important role in maintaining the health and function of the human macula. In this review article, we assess the value of non-invasive quantification of macular pigment levels and distributions to identify individuals potentially at risk for visual disability or catastrophic vision loss from age-related macular degeneration, and we consider the strengths and weaknesses of the diverse measurement methods currently available. PMID:19854211

  1. 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

  2. Health state utilities in patients with diabetic retinopathy, diabetic macular oedema and age-related macular degeneration: a systematic review

    PubMed Central

    2013-01-01

    Background Health state utility values (HSUVs) are important in the assessment of the cost effectiveness of new interventions. In the case of visual conditions, models generally tend have tended to be built around a set of health states defined by visual acuity (VA). The aim of this review was to assess the impact of VA on HSUVs in patients with diabetic retinopathy, diabetic macular oedema or age-related macular degeneration. Methods A systematic literature search was undertaken in major bibliographic databases to identify articles reporting on the relationship between HSUVs and vision. Data were extracted for population characteristics, visual levels and estimated utilities. Evidence from reported statistical models, where available, was considered in the evaluation of vision in the better-seeing eye and the worse-seeing eye. Due to the heterogeneity of included studies, a narrative synthesis was undertaken. Results Of the 17 relevant studies, 9 studies had data that could be used in the analysis of the impact of vision on HSUVs. Visual loss was associated with a marked impact on health utilities. However, the relationship was not comparable between conditions or by measure of HSUVs. Key results included the finding that overall, self-rated time-trade off estimates were more likely to discriminate between different VA levels than EQ-5D values. Additionally, a stronger correlation was observed between HSUVs and better-seeing eye VA compared to worse-seeing eye VA. Conclusions Visual acuity has a significant impact on HSUVs. Nevertheless, care must be taken in the interpretation and use of estimates in cost-effectiveness models due to differences in measures and population diversity. PMID:24304921

  3. 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

  4. Black Holes in String Theory

    NASA Astrophysics Data System (ADS)

    Bena, Iosif; El-Showk, Sheer; Vercnocke, Bert

    These lectures notes provide a fast-track introduction to modern developments in black hole physics within string theory, including microscopic computations of the black hole entropy as well as construction and quantization of microstates using supergravity. These notes are largely self-contained and should be accessible to students at an early PhD or Masters level. Topics covered include the black holes in supergravity, D-branes, Strominger-Vafa's computation of the black hole entropy via D-branes, AdS-CFT and its applications to black hole phyisics, multicenter solutions, and the geometric quantization of the latter.

  5. [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

  6. 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.

  7. Prisons of light : black holes

    NASA Astrophysics Data System (ADS)

    Ferguson, Kitty

    What is a black hole? Could we survive a visit to one -- perhaps even venture inside? Have we yet discovered any real black holes? And what do black holes teach us about the mysteries of our Universe? These are just a few of the tantalizing questions examined in this tour-de-force, jargon-free review of one of the most fascinating topics in modern science. In search of the answers, we trace a star from its birth to its death throes, take a hypothetical journey to the border of a black hole and beyond, spend time with some of the world's leading theoretical physicists and astronomers, and take a whimsical look at some of the wild ideas black holes have inspired. Prisons of Light - Black Holes is comprehensive and detailed. Yet Kitty Ferguson's lightness of touch and down-to-earth analogies set this book apart from all others on black holes and make it a wonderfully stimulating and entertaining read.

  8. 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.

  9. 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.

  10. 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.

  11. Age-related macular degeneration: beyond anti-angiogenesis.

    PubMed

    Kent, David L

    2014-01-06

    Recently, anti-vascular endothelial growth factor therapies for neovascular age-related macular degeneration have been developed. These agents, originally developed for their anti-angiogenic mechanism of action, probably also work through an anti-permeability effect in preventing or reducing the amount of leakage from submacular neovascular tissue. Other treatment modalities include laser photocoagulation, photodynamic therapy with verteporfin, and submacular surgery. In reality, these latter treatments can be similarly categorized as anti-angiogenic because their sole aim is destroying or removing choroidal neovascularization (CNV). At the cellular level, CNV resembles stereotypical tissue repair that consists of several matricellular components in addition to neovascularization. In the retina, the clinical term CNV is a misnomer since the term may more appropriately be referred to as aberrant submacular repair. Furthermore, CNV raises a therapeutic conundrum: To complete or correct any reparative process in the body, angiogenesis becomes an essential component. Anti-angiogenic therapy, in all its guises, arrests repair and causes the hypoxic environment to persist, thus fueling pro-angiogenesis and further development of CNV as a component of aberrant repair. However, we realize that anti-vascular endothelial growth factor therapy preserves vision in patients with age-related macular degeneration, albeit temporarily and therefore, repeated treatment is needed. More importantly, however, anti-angiogenic therapy demonstrates that we can at the very least tolerate neovascular tissue beneath the macula and preserve vision in contrast to our historical approach of total vascular destruction. In this clinical scenario, it may be possible to look beyond anti-angiogenesis if our goal is facilitating submacular repair without destroying the neurosensory retina. Thus, in this situation of neovascular tolerance, it may be timely to consider treatments that facilitate

  12. 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.

  13. Reflection-based imaging of macular pigment distributions in infants and children.

    PubMed

    Sharifzadeh, Mohsen; Bernstein, Paul S; Gellermann, Werner

    2013-11-01

    We have developed a reflection-based capability of the RetCam(®) platform, an FDA-cleared pediatric retinal-imaging instrument, for the purpose of measuring macular pigment levels as well as their spatial distributions in infants and children. Our modifications include narrow-band blue-wavelength excitation of the macular pigment absorption in combination with spectrally selective blue-wavelength readout of the reflection signals received by the instrument's CCD detector array. Furthermore, an algorithm is developed that allows the computation of optical density maps for the macular pigment relative to peripheral retinal areas. This made it possible for the first time to directly measure macular pigment levels and their spatial features in the developing human retina. In contrast to adults, infants with measurable pigment levels had almost exclusively a narrow, circularly symmetric, pigment distribution. The described methodology holds promise for future investigations into the role of macular pigment in the developing human retina and the effect of dietary interventions in diseases resulting from a lack of normal carotenoid levels.

  14. Changes in Central Macular Thickness following Single Session Multispot Panretinal Photocoagulation

    PubMed Central

    Watanachai, Nawat; Choovuthayakorn, Janejit; Patikulsila, Direk; Ittipunkul, Nimitr

    2015-01-01

    Purpose. To determine changes in central subfield (CSF) macular thickness and best corrected visual acuity (BCVA) following single session, multispot panretinal photocoagulation (PRP). Methods. Forty eyes of 33 patients with newly diagnosed proliferative diabetic retinopathy were treated with single session, 20-millisecond, multispot PRP. Changes in central macular thickness and BCVA at 4- and 12-week follow-up were compared to baseline measurements. Results. Each eye received a mean (SD) of 2,750 (686.7) laser spots. At 4-week follow-up, there was a statistically significant 24.0 μm increase in mean CSF thickness (P = 0.001), with a 17.4 μm increase from baseline at 12-week follow-up (P = 0.002). Mean logMAR BCVA increased by 0.05 logMAR units (P = 0.03) at 4-week follow-up. At 12-week follow-up, BCVA had almost returned to normal with only an increase of 0.02 logMAR units compared to baseline (P = 0.39). Macular edema occurred in 2 eyes (5%) at 12-week follow-up. Conclusions. Macular thickening occurs following single session, 20-millisecond, multispot PRP, with a corresponding, mild change in BCVA. However, the incidence of macular edema appears to be low in these patients. Single session, 20-millisecond, multispot PRP appears to be a safe treatment for patients with proliferative diabetic retinopathy. PMID:25694825

  15. 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.

  16. 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.

  17. 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.

  18. Black Holes in Higher Dimensions

    NASA Astrophysics Data System (ADS)

    Horowitz, Gary T.

    2012-04-01

    List of contributors; Preface; Part I. Introduction: 1. Black holes in four dimensions Gary Horowitz; Part II. Five Dimensional Kaluza-Klein Theory: 2. The Gregory-Laflamme instability Ruth Gregory; 3. Final state of Gregory-Laflamme instability Luis Lehner and Frans Pretorius; 4. General black holes in Kaluza-Klein theory Gary Horowitz and Toby Wiseman; Part III. Higher Dimensional Solutions: 5. Myers-Perry black holes Rob Myers; 6. Black rings Roberto Emparan and Harvey Reall; Part IV. General Properties: 7. Constraints on the topology of higher dimensional black holes Greg Galloway; 8. Blackfolds Roberto Emparan; 9. Algebraically special solutions in higher dimensions Harvey Reall; 10. Numerical construction of static and stationary black holes Toby Wiseman; Part V. Advanced Topics: 11. Black holes and branes in supergravity Don Marolf; 12. The gauge/gravity duality Juan Maldacena; 13. The fluid/gravity correspondence Veronika Hubeny, Mukund Rangamani and Shiraz Minwalla; 14. Horizons, holography and condensed matter Sean Hartnoll; Index.

  19. Particle-Hole Ladders

    NASA Astrophysics Data System (ADS)

    Feldman, Joel; Knörrer, Horst; Trubowitz, Eugene

    A self contained analysis demonstrates that the sum of all particle-hole ladder contributions for a two dimensional, weakly coupled fermion gas with a strictly convex Fermi curve at temperature zero is bounded. This is used in our construction of two dimensional Fermi liquids. This article contains the statements of the main results. The proofs are contained in the full, electronic, article. Electronic Supplementary Material: Supplementary material is available in the online version of this article at http://dx.doi.org/10.1007/s00220-004-1038-2.

  20. 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

  1. The Antarctic ozone hole

    NASA Astrophysics Data System (ADS)

    Jones, Anna E.

    2008-07-01

    Since the mid 1970s, the ozone layer over Antarctica has experienced massive destruction during every spring. In this article, we will consider the atmosphere, and what ozone and the ozone layer actually are. We explore the chemistry responsible for the ozone destruction, and learn about why conditions favour ozone destruction over Antarctica. For the historical perspective, the events leading up to the discovery of the 'hole' are presented, as well as the response from the international community and the measures taken to protect the ozone layer now and into the future.

  2. Stereotactic radiotherapy in neovascular age-related macular degeneration

    PubMed Central

    Ranjbar, Mahdy; Kurz, Maximilian; Holzhey, Annekatrin; Melchert, Corinna; Rades, Dirk; Grisanti, Salvatore

    2016-01-01

    Abstract Stereotactic radiotherapy (SRT) is a new approach to treat neovascular age-related macular degeneration (nAMD). The INTREPID trial suggested that SRT could reduce the frequency of regular intravitreal injections (IVIs) with antivascular endothelial growth factor drugs, which are necessary to control disease activity. However, the efficacy of SRT in nAMD and resulting morphological changes have not been validated under real-life circumstances, an issue, which we would like to address in this retrospective analysis. Patients who met the INTREPID criteria for best responders were eligible for SRT. A total of 32 eyes of 32 patients were treated. Thereafter, patients were examined monthly for 12 months and received pro re nata IVI of aflibercept or ranibizumab. Outcome measures were: mean number of injections, best-corrected visual acuity, and morphological changes of the outer retina-choroid complex as well as patient safety. Mean number of IVI decreased by almost 50% during the 12 months after SRT compared to the year before, whereas visual acuity increased by one line (logMAR). Morphological evaluation showed that most changes affect outer retinal layers. Stereotactic radiotherapy significantly reduced IVI retreatment in nAMD patients under real-life circumstances. Therefore, SRT might be the first step to stop visual loss as a result of IVI undertreatment, which is a major risk. PMID:28033280

  3. Activity loss and depression in age-related macular degeneration.

    PubMed

    Rovner, Barry W; Casten, Robin J

    2002-01-01

    Age-related macular degeneration (AMD) is the most frequent cause of severe vision loss in older persons and is associated with high rates of disability and depression. The authors evaluated 51 patients with bilateral AMD to investigate the interrelationships of disease severity, disability, and depression and focused on loss of valued activities as an emblematic disabling consequence of AMD. They characterized depression by the Center for Epidemiologic Studies-Depression (CES-D) score, a syndromal state based on the CES-D, and as a level of distress (Index of Affective Suffering; IAS). Thirty subjects (58.8%) had loss of a valued, discretionary activity. They had worse visual acuity and more depressive symptoms and were represented in higher IAS levels than other subjects. Visual acuity was significantly correlated with IAS levels, but not with CES-D scores or syndromal depression. A regression model demonstrated that activity loss mediated the relationship between visual acuity and IAS level. Affective distress occurs in AMD, largely to the extent that valued activities are relinquished because of vision loss. IAS levels best illuminated this relationship, suggesting the value of this dimension of affective functioning in studies of the consequences of chronic disease.

  4. 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.

  5. Fundus Autofluorescence in Age-related Macular Degeneration

    PubMed Central

    Ly, Angelica; Nivison-Smith, Lisa; Assaad, Nagi; Kalloniatis, Michael

    2017-01-01

    ABSTRACT Fundus autofluorescence (FAF) provides detailed insight into the health of the retinal pigment epithelium (RPE). This is highly valuable in age-related macular degeneration (AMD) as RPE damage is a hallmark of the disease. The purpose of this paper is to critically appraise current clinical descriptions regarding the appearance of AMD using FAF and to integrate these findings into a chair-side reference. A wide variety of FAF patterns have been described in AMD, which is consistent with the clinical heterogeneity of the disease. In particular, FAF imaging in early to intermediate AMD has the capacity to reveal RPE alterations in areas that appear normal on funduscopy, which aids in the stratification of cases and may have visually significant prognostic implications. It can assist in differential diagnoses and also represents a reliable, sensitive method for distinguishing reticular pseudodrusen. FAF is especially valuable in the detection, evaluation, and monitoring of geographic atrophy and has been used as an endpoint in clinical trials. In neovascular AMD, FAF reveals distinct patterns of classic choroidal neovascularization noninvasively and may be especially useful for determining which eyes are likely to benefit from therapeutic intervention. FAF represents a rapid, effective, noninvasive imaging method that has been underutilized, and incorporation into the routine assessment of AMD cases should be considered. However, the practicing clinician should also be aware of the limitations of the modality, such as in the detection of foveal involvement and in the distinction of phenotypes (hypo-autofluorescent drusen from small areas of geographic atrophy). PMID:27668639

  6. Ocular surface temperature in age-related macular degeneration.

    PubMed

    Sodi, Andrea; Matteoli, Sara; Giacomelli, Giovanni; Finocchio, Lucia; Corvi, Andrea; Menchini, Ugo

    2014-01-01

    Background. The aim of this study is to investigate the ocular thermographic profiles in age-related macular degeneration (AMD) eyes and age-matched controls to detect possible hemodynamic abnormalities, which could be involved in the pathogenesis of the disease. Methods. 32 eyes with early AMD, 37 eyes with atrophic AMD, 30 eyes affected by untreated neovascular AMD, and 43 eyes with fibrotic AMD were included. The control group consisted of 44 healthy eyes. Exclusion criteria were represented by any other ocular diseases other than AMD, tear film abnormalities, systemic cardiovascular abnormalities, diabetes mellitus, and a body temperature higher than 37.5°C. A total of 186 eyes without pupil dilation were investigated by infrared thermography (FLIR A320). The ocular surface temperature (OST) of three ocular points was calculated by means of an image processing technique from the infrared images. Two-sample t-test and one-way analysis of variance (ANOVA) test were used for statistical analyses. Results. ANOVA analyses showed no significant differences among AMD groups (P value >0.272). OST in AMD patients was significantly lower than in controls (P > 0.05). Conclusions. Considering the possible relationship between ocular blood flow and OST, these findings might support the central role of ischemia in the pathogenesis of AMD.

  7. Smooth pursuit eye movements in patients with macular degeneration

    PubMed Central

    Shanidze, Natela; Fusco, Giovanni; Potapchuk, Elena; Heinen, Stephen; Verghese, Preeti

    2016-01-01

    Currently, there are no quantitative studies of smooth pursuit, a behavior attributed to the fovea, in individuals with macular degeneration (MD). We hypothesize that pursuit in MD patients depends on the relative positions of the scotoma and target trajectory. We tested this hypothesis with a scanning laser ophthalmoscope (SLO), which allows for direct visualization of the target on the damaged retina. Monocular microperimetry and eye movements were assessed in eleven individuals with differing degrees of MD. Observers were asked to visually track a 1.7° target that moved in one of eight radial directions at 5°/s–6°/s. Consistent with our hypothesis, pursuit metrics depended on whether the target moved into or out of scotoma. Pursuit gains decreased with increasing scotoma extent in the target's heading direction (p = 0.017). Latencies were higher when the scotoma was present along the target trajectory (in either starting or heading directions, p < 0.001). Furthermore, an analysis of retinal position shows that targets fell on the fixational locus nearly 50% of the time. The results suggest that MD patients are capable of smooth pursuit eye movements, but are limited by target trajectory and scotoma characteristics. PMID:26830707

  8. Cellular models and therapies for age-related macular degeneration

    PubMed Central

    Forest, David L.; Johnson, Lincoln V.; Clegg, Dennis O.

    2015-01-01

    ABSTRACT Age-related macular degeneration (AMD) is a complex neurodegenerative visual disorder that causes profound physical and psychosocial effects. Visual impairment in AMD is caused by the loss of retinal pigmented epithelium (RPE) cells and the light-sensitive photoreceptor cells that they support. There is currently no effective treatment for the most common form of this disease (dry AMD). A new approach to treating AMD involves the transplantation of RPE cells derived from either human embryonic or induced pluripotent stem cells. Multiple clinical trials are being initiated using a variety of cell therapies. Although many animal models are available for AMD research, most do not recapitulate all aspects of the disease, hampering progress. However, the use of cultured RPE cells in AMD research is well established and, indeed, some of the more recently described RPE-based models show promise for investigating the molecular mechanisms of AMD and for screening drug candidates. Here, we discuss innovative cell-culture models of AMD and emerging stem-cell-based therapies for the treatment of this vision-robbing disease. PMID:26035859

  9. Quantification of retinal layer thickness changes in acute macular neuroretinopathy

    PubMed Central

    Munk, Marion R; Beck, Marco; Kolb, Simone; Larsen, Michael; Hamann, Steffen; Valmaggia, Christophe; Zinkernagel, Martin S

    2017-01-01

    Purpose To quantitatively evaluate retinal layer thickness changes in acute macular neuroretinopathy (AMN). Methods AMN areas were identified using near-infrared reflectance (NIR) images. Intraretinal layer segmentation using Heidelberg software was performed. The inbuilt ETDRS -grid was moved onto the AMN lesion and the mean retinal layer thicknesses of the central grid were recorded and compared with the corresponding area of the fellow eye at initial presentation and during follow-up. Results Eleven patients were included (mean age 26±6 years). AMN lesions at baseline had a significantly thinner outer nuclear layer (ONL) (51±21 µm vs 73±17 µm, p=0.002). The other layers, including inner nuclear layer (37±8 µm vs 38±6 µm, p=0.9) and outer plexiform layer (OPL) (45±19 µm vs 33±16 µm, p=0.1) did not show significant differences between the study eyes and fellow eyes. Adjacent to NIR image lesions, areas of OPL thickening were identified (study eye: 50±14 µm vs fellow eye: 39±16 µm, p=0.005) with corresponding thinning of ONL (study eye: 52±16 µm vs fellow eye: 69±16 µm, p=0.002). Conclusions AMN presents with characteristic quantitative retinal changes and the extent of the lesion may be more extensive than initially presumed from NIR image lesions. PMID:27170518

  10. Fundus autofluorescence in exudative age-related macular degeneration.

    PubMed

    Peng, Q; Dong, Y; Zhao, P Q

    2013-12-02

    The aim of this study was to investigate the characteristics of fundus autofluorescence (FAF) in patients with wet (exudative) age-related macular degeneration (AMD). Color fundus photographs, fundus fluorescein angiograms, indocyanine green angiograms, and FAF images were obtained from 61 patients (72 eyes) with exudative AMD. The FAF results for different patterns of exudative AMD were compared to those revealed by other fundus images. Of the 72 eyes evaluated, which were classified into three patterns based on the results of fundus fluorescein angiography, 68 had abnormal FAF. Forty-six eyes (63.9%) had classic wet AMD with abnormal FAF. Among these, 10 exhibited a slightly decreased FAF with near-normal or background FAF signal at the center of the lesion area; 36 demonstrated not only decreased FAF at the center of the lesion but also an increased FAF signal toward the lesion edge. Sixteen eyes (22.2%) had occult wet AMD, of which 12 exhibited heterogeneous fluorescence at the lesion site; 4 yielded normal FAF images. Ten eyes (13.9%) had a mixed pattern of wet AMD with abnormal FAF. FAF imaging suggested that the areas of blood and exudates decreased; however, fluorescence angiography revealed that lesions with hyperfluorescence had background or slightly increased FAF. These results showed that various patterns of wet AMD exhibit different autofluorescence characteristics. These represent the functional and metabolic features of retinal pigment epithelial cells. Therefore, FAF can be used to monitor disease development and evaluate the severity and prognosis of AMD.

  11. Therapeutic Modalities of Exudative Age-related Macular Degeneration

    PubMed Central

    Mavija, Milka; Alimanovic, Emina; Jaksic, Vesna; Kasumovic, Sanja Sefic; Cekic, Sonja; Stamenkovic, Miroslav

    2014-01-01

    Introduction: Age-related macular degeneration (AMD) is a leading cause of irreversible serious vision damage in persons over 50 years of age. In treating AMD many medicaments are applied such as inhibitors of vascular endothelial growth factor (VEGF), have been very carefully included over the last few years after a series of study research. Aims: To analyze the past methods of treatment, discuss emerging therapies which could advance the treatment of exudative AMD. The past anti-VEGF therapies require frequent repetitions of administration, with uncertain visual acuity recovery, as not all patients react to anti-VEGF therapy. Consequently, there is a need to find out additional therapies which could improve the treatment of exudative AMD. The real aim in the treating of AMD is to prevent CNV development. Methods: A survey of the current clinical research and results in the field of the present and future treatments of exudative AMD. Results: There are many areas of research into new methods of the exudative AMD treatment. Conclusion: The future therapies for exudative AMD treatment have a potential not only to reduce the frequency of administration and follow-up visits, but also to improve effects of treatment by targeting additional ways of CNV development, increasing the aptitude of target binding and extending durability of treatment. PMID:25568535

  12. Automatic segmentation of microcystic macular edema in OCT

    PubMed Central

    Lang, Andrew; Carass, Aaron; Swingle, Emily K.; Al-Louzi, Omar; Bhargava, Pavan; Saidha, Shiv; Ying, Howard S.; Calabresi, Peter A.; Prince, Jerry L.

    2014-01-01

    Microcystic macular edema (MME) manifests as small, hyporeflective cystic areas within the retina. For reasons that are still largely unknown, a small proportion of patients with multiple sclerosis (MS) develop MME—predominantly in the inner nuclear layer. These cystoid spaces, denoted pseudocysts, can be imaged using optical coherence tomography (OCT) where they appear as small, discrete, low intensity areas with high contrast to the surrounding tissue. The ability to automatically segment these pseudocysts would enable a more detailed study of MME than has been previously possible. Although larger pseudocysts often appear quite clearly in the OCT images, the multi-frame averaging performed by the Spectralis scanner adds a significant amount of variability to the appearance of smaller pseudocysts. Thus, simple segmentation methods only incorporating intensity information do not perform well. In this work, we propose to use a random forest classifier to classify the MME pixels. An assortment of both intensity and spatial features are used to aid the classification. Using a cross-validation evaluation strategy with manual delineation as ground truth, our method is able to correctly identify 79% of pseudocysts with a precision of 85%. Finally, we constructed a classifier from the output of our algorithm to distinguish clinically identified MME from non-MME subjects yielding an accuracy of 92%. PMID:25657884

  13. 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

  14. Gene transfer for neovascular age-related macular degeneration.

    PubMed

    Campochiaro, Peter A

    2011-05-01

    Age-related macular degeneration (AMD) is a complex disease that has two phases: a degenerative phase often referred to as nonneovascular AMD (non-NVAMD) or dry AMD and a phase dominated by growth of new blood vessels in the subretinal space, referred to as NVAMD or wet AMD. Advances in the understanding of the molecular pathogenesis of NVAMD have led to new drug therapies that have provided major benefits to patients. However, those treatments require frequent intraocular injections that in many patients must be continued indefinitely to maintain visual benefits. Gene transfer to augment expression of endogenous antiangiogenic proteins is an alternative approach that has the potential to provide long-term stability in patients with NVAMD. Studies in animal models that mimic aspects of NVAMD have identified several possible transgenes, and a clinical trial in patients with advanced NVAMD has suggested that the approach may be feasible. Many important questions remain, but the rationale and preliminary data are compelling. The results of two ongoing clinical trials may answer several of the questions and help direct future research.

  15. Idiopathic eruptive macular pigmentation with papillomatosis: Report of nine cases.

    PubMed

    Joshi, Rajiv

    2007-01-01

    Nine patients, seven males and two females aged 6-14 years, presented with extensive, asymptomatic, brown-black macules and mildly elevated, pigmented lesions of a few months' duration. The sites affected were the face, trunk and proximal extremities. The skin lesions were discrete and individual lesions were less than 2 cm in size. The clinical diagnoses rendered by the referring physicians were lichen planus pigmentosus, urticaria pigmentosa, erythema dyschromicum perstans and postinflammatory hyperpigmentation. Histology in all nine cases showed papillomatosis of the dermis with prominent pigmentation of the basal layer (pigmented papillomatosis) without any significant dermal inflammation. Two cases had spores of Pityrosporum ovale in the thickened horny layer, one of which also had, in addition, bacterial colonies in the stratum corneum. The pigmentation resolved on its own over several months. This presentation is similar to the previously described idiopathic eruptive macular pigmentation with the additional histological finding of papillomatosis that is being described for the first time and may be nosologically related to acanthosis nigricans and confluent and reticulate papillomatosis.

  16. Reticular pseudodrusen in age-related macular degeneration.

    PubMed

    Hogg, Ruth Esther

    2014-08-01

    Historically, drusen, which are recognized as the hallmark of age-related macular degeneration (AMD), have been described in terms of size, margins, and texture, and several studies have emphasized the importance of large soft drusen particularly when combined with focal pigmentary irregularities in determining the risk of progression to neovascular AMD. However, recent developments in imaging over the past decade have revealed a further distinct phenotype strongly associated with the development of late AMD, namely, reticular pseudodrusen (RPD) or reticular drusen. Reticular pseudodrusen appear as yellowish interlacing networks in the fundus and, although visible on color photography, are better visualized using infrared imaging or spectral domain optical coherence tomography. Studies correlating spectral domain optical coherence tomography and confocal scanning laser ophthalmoscopy have shown that RPD are subretinal deposits located internal to the retinal pigment epithelium in contrast to traditional drusen, which are located external to the retinal pigment epithelium. As multiple longitudinal studies have revealed RPD are strong predictors for progression to both neovascular AMD and geographic atrophy, the interest in understanding the role that RPD play in the pathogenesis of AMD has grown. This review focuses on the current literature concerning RPD and considers what is currently known regarding their epidemiology, risk factors, appearance in both retinal imaging and histology, impact on visual function, relationship to other AMD lesions, and association with the development of late AMD.

  17. 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

  18. Mechanism of inflammation in age-related macular degeneration.

    PubMed

    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.

  19. 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

  20. Effects of Age-Related Macular Degeneration on Postural Sway

    PubMed Central

    Chatard, Hortense; Tepenier, Laure; Jankowski, Olivier; Aussems, Antoine; Allieta, Alain; Beydoun, Talal; Salah, Sawsen; Bucci, Maria P.

    2017-01-01

    Purpose: To compare the impact of unilateral vs. bilateral age-related macular degeneration (AMD) on postural sway, and the influence of different visual conditions. The hypothesis of our study was that the impact of AMD will be different between unilateral and bilateral AMD subjects compared to age-matched healthy elderly. Methods: Postural stability was measured with a platform (TechnoConcept®) in 10 elderly unilateral AMD subjects (mean age: 71.1 ± 4.6 years), 10 elderly bilateral AMD subjects (mean age: 70.8 ± 6.1 years), and 10 healthy age-matched control subjects (mean age: 69.8 ± 6.3 years). Four visual conditions were tested: both eyes viewing condition (BEV), dominant eye viewing (DEV), non-dominant eye viewing (NDEV), and eyes closed (EC). We analyzed the surface area, the length, the mean speed, the anteroposterior (AP), and mediolateral (ML) displacement of the center of pressure (CoP). Results: Bilateral AMD subjects had a surface area (p < 0.05) and AP displacement of the CoP (p < 0.01) higher than healthy elderly. Unilateral AMD subjects had more AP displacement of the CoP (p < 0.05) than healthy elderly. Conclusions: We suggest that ADM subjects could have poor postural adaptive mechanisms leading to increase their postural instability. Further studies will aim to improve knowledge on such issue and to develop reeducation techniques in these patients.

  1. Object crowding in age-related macular degeneration

    PubMed Central

    Wallace, Julian M.; Chung, Susana T. L.; Tjan, Bosco S.

    2017-01-01

    Crowding, the phenomenon of impeded object identification due to clutter, is believed to be a key limiting factor of form vision in the peripheral visual field. The present study provides a characterization of object crowding in age-related macular degeneration (AMD) measured at the participants' respective preferred retinal loci with binocular viewing. Crowding was also measured in young and age-matched controls at the same retinal locations, using a fixation-contingent display paradigm to allow unlimited stimulus duration. With objects, the critical spacing of crowding for AMD participants was not substantially different from controls. However, baseline contrast energy thresholds in the noncrowded condition were four times that of the controls. Crowding further exacerbated deficits in contrast sensitivity to three times the normal crowding-induced contrast energy threshold elevation. These findings indicate that contrast-sensitivity deficit is a major limiting factor of object recognition for individuals with AMD, in addition to crowding. Focusing on this more tractable deficit of AMD may lead to more effective remediation and technological assistance. PMID:28129416

  2. 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.

  3. Impact of age related macular degeneration on quality of life

    PubMed Central

    Hassell, J B; Lamoureux, E L; Keeffe, J E

    2006-01-01

    Aims To describe the impact of age related macular degeneration (AMD) on quality of life and explore the association with vision, health, and demographic variables. Methods Adult participants diagnosed with AMD and with impaired vision (visual acuity <6/12) were assessed with the Impact of Vision Impairment (IVI) questionnaire. Participants rated the extent that vision restricted participation in activities affecting quality of life and completed the Short Form General Health Survey (SF‐12) and a sociodemographic questionnaire. Results The mean age of the 106 participants (66% female) was 83.6 years (range 64–98). One quarter had mild vision impairment, (VA<6/12–6/18) and 75% had moderate or severely impaired vision. Participants reported from at least “a little” concern on 23 of the 32 IVI items including reading, emotional health, mobility, and participation in relevant activities. Those with mild and moderate vision impairment were similarly affected but significantly different from those with severe vision loss (p<0.05). Distance vision was associated with IVI scores but not age, sex, or duration of vision loss. Conclusion AMD affects many quality of life related activities and not just those related to reading. Referral to low vision care services should be considered for people with mild vision loss and worse. PMID:16622089

  4. Seven new loci associated with age-related macular degeneration.

    PubMed

    Fritsche, Lars G; Chen, Wei; Schu, Matthew; Yaspan, Brian L; Yu, Yi; Thorleifsson, Gudmar; Zack, Donald J; Arakawa, Satoshi; Cipriani, Valentina; Ripke, Stephan; Igo, Robert P; Buitendijk, Gabriëlle H S; Sim, Xueling; Weeks, Daniel E; Guymer, Robyn H; Merriam, Joanna E; Francis, Peter J; Hannum, Gregory; Agarwal, Anita; Armbrecht, Ana Maria; Audo, Isabelle; Aung, Tin; Barile, Gaetano R; Benchaboune, Mustapha; Bird, Alan C; Bishop, Paul N; Branham, Kari E; Brooks, Matthew; Brucker, Alexander J; Cade, William H; Cain, Melinda S; Campochiaro, Peter A; Chan, Chi-Chao; Cheng, Ching-Yu; Chew, Emily Y; Chin, Kimberly A; Chowers, Itay; Clayton, David G; Cojocaru, Radu; Conley, Yvette P; Cornes, Belinda K; Daly, Mark J; Dhillon, Baljean; Edwards, Albert O; Evangelou, Evangelos; Fagerness, Jesen; Ferreyra, Henry A; Friedman, James S; Geirsdottir, Asbjorg; George, Ronnie J; Gieger, Christian; Gupta, Neel; Hagstrom, Stephanie A; Harding, Simon P; Haritoglou, Christos; Heckenlively, John R; Holz, Frank G; Hughes, Guy; Ioannidis, John P A; Ishibashi, Tatsuro; Joseph, Peronne; Jun, Gyungah; Kamatani, Yoichiro; Katsanis, Nicholas; N Keilhauer, Claudia; Khan, Jane C; Kim, Ivana K; Kiyohara, Yutaka; Klein, Barbara E K; Klein, Ronald; Kovach, Jaclyn L; Kozak, Igor; Lee, Clara J; Lee, Kristine E; Lichtner, Peter; Lotery, Andrew J; Meitinger, Thomas; Mitchell, Paul; Mohand-Saïd, Saddek; Moore, Anthony T; Morgan, Denise J; Morrison, Margaux A; Myers, Chelsea E; Naj, Adam C; Nakamura, Yusuke; Okada, Yukinori; Orlin, Anton; Ortube, M Carolina; Othman, Mohammad I; Pappas, Chris; Park, Kyu Hyung; Pauer, Gayle J T; Peachey, Neal S; Poch, Olivier; Priya, Rinki Ratna; Reynolds, Robyn; Richardson, Andrea J; Ripp, Raymond; Rudolph, Guenther; Ryu, Euijung; Sahel, José-Alain; Schaumberg, Debra A; Scholl, Hendrik P N; Schwartz, Stephen G; Scott, William K; Shahid, Humma; Sigurdsson, Haraldur; Silvestri, Giuliana; Sivakumaran, Theru A; Smith, R Theodore; Sobrin, Lucia; Souied, Eric H; Stambolian, Dwight E; Stefansson, Hreinn; Sturgill-Short, Gwen M; Takahashi, Atsushi; Tosakulwong, Nirubol; Truitt, Barbara J; Tsironi, Evangelia E; Uitterlinden, André G; van Duijn, Cornelia M; Vijaya, Lingam; Vingerling, Johannes R; Vithana, Eranga N; Webster, Andrew R; Wichmann, H-Erich; Winkler, Thomas W; Wong, Tien Y; Wright, Alan F; Zelenika, Diana; Zhang, Ming; Zhao, Ling; Zhang, Kang; Klein, Michael L; Hageman, Gregory S; Lathrop, G Mark; Stefansson, Kari; Allikmets, Rando; Baird, Paul N; Gorin, Michael B; Wang, Jie Jin; Klaver, Caroline C W; Seddon, Johanna M; Pericak-Vance, Margaret A; Iyengar, Sudha K; Yates, John R W; Swaroop, Anand; Weber, Bernhard H F; Kubo, Michiaki; Deangelis, Margaret M; Léveillard, Thierry; Thorsteinsdottir, Unnur; Haines, Jonathan L; Farrer, Lindsay A; Heid, Iris M; Abecasis, Gonçalo R

    2013-04-01

    Age-related macular degeneration (AMD) is a common cause of blindness in older individuals. To accelerate the understanding of AMD biology and help design new therapies, we executed a collaborative genome-wide association study, including >17,100 advanced AMD cases and >60,000 controls of European and Asian ancestry. We identified 19 loci associated at P < 5 × 10(-8). These loci show enrichment for genes involved in the regulation of complement activity, lipid metabolism, extracellular matrix remodeling and angiogenesis. Our results include seven loci with associations reaching P < 5 × 10(-8) for the first time, near the genes COL8A1-FILIP1L, IER3-DDR1, SLC16A8, TGFBR1, RAD51B, ADAMTS9 and B3GALTL. A genetic risk score combining SNP genotypes from all loci showed similar ability to distinguish cases and controls in all samples examined. Our findings provide new directions for biological, genetic and therapeutic studies of AMD.

  5. Pharmacologic therapies for diabetic retinopathy and diabetic macular edema.

    PubMed

    Rechtman, Ehud; Harris, Alon; Garzozi, Hanna J; Ciulla, Thomas A

    2007-12-01

    Diabetic retinopathy (DR) and diabetic macular edema (DME) are leading causes of blindness in the working-aged population of most developed countries. The increasing number of persons with diabetes worldwide suggests that DR/DME will continue to be major contributors to vision loss and associated functional impairment for years to come. Early detection of retinopathy in persons with diabetes is critical in preventing visual loss, but current methods of screening fail to identify a sizable number of high-risk patients. The control of diabetes-associated metabolic abnormalities (ie, hyperglycemia, hyperlipidemia, and hypertension) is also important in preserving visual function, as these conditions have been identified as risk factors for both the development and progression of DR/DME. The non-pharmacologic interventions for DR/DME, laser photocoagulation and vitrectomy, only target advanced stages of disease. Several biochemical mechanisms, including increased vascular endothelial growth factor production, protein kinase C beta activation, oxidative stress, and accumulation of intracellular sorbitol and advanced glycosylation end products, may contribute to the vascular disruptions that characterize DR/DME. The inhibition of these pathways holds the promise of the intervention for diabetic retinopathy with higher success rate and also at earlier, non-sight-threatening stages.

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

    PubMed

    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.

  7. Ocular Surface Temperature in Age-Related Macular Degeneration

    PubMed Central

    Sodi, Andrea; Giacomelli, Giovanni; Corvi, Andrea; Menchini, Ugo

    2014-01-01

    Background. The aim of this study is to investigate the ocular thermographic profiles in age-related macular degeneration (AMD) eyes and age-matched controls to detect possible hemodynamic abnormalities, which could be involved in the pathogenesis of the disease. Methods. 32 eyes with early AMD, 37 eyes with atrophic AMD, 30 eyes affected by untreated neovascular AMD, and 43 eyes with fibrotic AMD were included. The control group consisted of 44 healthy eyes. Exclusion criteria were represented by any other ocular diseases other than AMD, tear film abnormalities, systemic cardiovascular abnormalities, diabetes mellitus, and a body temperature higher than 37.5°C. A total of 186 eyes without pupil dilation were investigated by infrared thermography (FLIR A320). The ocular surface temperature (OST) of three ocular points was calculated by means of an image processing technique from the infrared images. Two-sample t-test and one-way analysis of variance (ANOVA) test were used for statistical analyses. Results. ANOVA analyses showed no significant differences among AMD groups (P value >0.272). OST in AMD patients was significantly lower than in controls (P > 0.05). Conclusions. Considering the possible relationship between ocular blood flow and OST, these findings might support the central role of ischemia in the pathogenesis of AMD. PMID:25436140

  8. Menus for Feeding Black Holes

    NASA Astrophysics Data System (ADS)

    Kocsis, Bence; Loeb, Abraham

    2014-09-01

    Black holes are the ultimate prisons of the Universe, regions of spacetime where the enormous gravity prohibits matter or even light to escape to infinity. Yet, matter falling toward the black holes may shine spectacularly, generating the strongest source of radiation. These sources provide us with astrophysical laboratories of extreme physical conditions that cannot be realized on Earth. This chapter offers a review of the basic menus for feeding matter onto black holes and discusses their observational implications.

  9. Thermodynamics of Accelerating Black Holes.

    PubMed

    Appels, Michael; Gregory, Ruth; Kubizňák, David

    2016-09-23

    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.

  10. Black holes and the multiverse

    SciTech Connect

    Garriga, Jaume; Vilenkin, Alexander; Zhang, Jun E-mail: vilenkin@cosmos.phy.tufts.edu

    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.

  11. 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.

  12. Ring Around the Black Hole

    NASA Technical Reports Server (NTRS)

    Wanjek, Christopher

    2003-01-01

    Regardless of size, black holes easily acquire accretion disks. Supermassive black holes can feast on the bountiful interstellar gas in galactic nuclei. Small black holes formed from collapsing stars often belong to binary systems in which a bulging companion star can spill some of its gas into the black hole s reach. In the chaotic mess of the accretion disk, atoms collide with one another. Swirling plasma reaches speeds upward of 10% that of light and glows brightly in many wavebands, particularly in X-rays. Gas gets blown back by a wind of radiation from the inner disk. New material enters the disks from different directions.

  13. 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.

  14. [Unilateral cystoid macular edema induced by citalopram--a case report].

    PubMed

    Alexík, M

    2011-10-01

    Citamopram is an antidepressant drug with fatigue, sleep disorders, appetite changes and visual impairment being the most common side effects. We are not aware of any published cases of cystoid macular edema following medication of this drug. We present a case of 55 year old woman with medical history of depression placed on Citalopram medication who noticed deterioration of right eye vision. Best corrected visual acuity was 20/120, ophthalmic coherence tomography and fluorescein angiography revealed cystoid macular edema. Two months following drug withdrawal edema disappeared and best corrected visual acuity improved to 20/32. Due to lack of other probable causes of edema and quick disappearance following drug withdrawal it is plausible to think of Citalopram as causative factor of cystoid macular edema in this patient.

  15. Hypotrichosis with juvenile macular dystrophy: a case report with molecular study.

    PubMed

    Vicente, Lucas Perez; Finzi, Simone; Susanna, Remo; Young, Terri L

    2017-01-01

    Hypotrichosis with juvenile macular dystrophy is a rare autosomal recessive disorder characterized by sparse scalp hair caused by hair follicle abnormalities as well as progressive retinal degeneration leading to blindness in the second or third decade of life. It is associated with mutations of the cadherin 3 (CDH3) gene, which result in abnormal expression of P-cadherin. Mutations in CDH3 are related to ectodermal dysplasia, ectrodactyly, and macular dystrophy. In this report, we describe an 11-year-old Iranian boy born with a missing left index fingernail and sparse scalp hair who later displayed macular pigmentary changes. Genetic testing of the CDH3 gene revealed a homozygous gene variant at exon 6 (640A>T). This novel in-frame mutation converts a lysine to a premature stop codon, altering synthesis of P-cadherin on chromosome 16q22.

  16. Advanced image processing for optical coherence tomographic angiography of macular diseases

    PubMed Central

    Zhang, Miao; Wang, Jie; Pechauer, Alex D.; Hwang, Thomas S.; Gao, Simon S.; Liu, Liang; Liu, Li; Bailey, Steven T.; Wilson, David J.; Huang, David; Jia, Yali

    2015-01-01

    This article provides an overview of advanced image processing for three dimensional (3D) optical coherence tomographic (OCT) angiography of macular diseases, including age-related macular degeneration (AMD) and diabetic retinopathy (DR). A fast automated retinal layers segmentation algorithm using directional graph search was introduced to separates 3D flow data into different layers in the presence of pathologies. Intelligent manual correction methods are also systematically addressed which can be done rapidly on a single frame and then automatically propagated to full 3D volume with accuracy better than 1 pixel. Methods to visualize and analyze the abnormalities including retinal and choroidal neovascularization, retinal ischemia, and macular edema were presented to facilitate the clinical use of OCT angiography. PMID:26713185

  17. Utility of optical coherence tomography in a case of bilateral congenital macular coloboma

    PubMed Central

    Muñoz de Escalona Rojas, José Enrique; Quereda Castañeda, Aurora; García García, Olga

    2016-01-01

    Macular coloboma is a congenital defect of the retina and choroid in the macular region. It may appear due to an intrauterine inflammation or a developmental abnormality. Familial hypomagnesemia with hypercalciuria and nephrocalcinosis (FHHNC) is a result of malformation of the renal tubule. Its combination with ocular manifestations may be genetic, specifically in case of claudin-19 (CLDN-19) gene mutations. The combination of FHHNC and ocular manifestations is not always present in these patients. Optical coherence tomography (OCT) helps us diagnose this condition by allowing us to evaluate and confirm the absence of retina layers without histological examination. Although genetic testing is necessary to diagnose mutational alterations of the CLDN-19 gene, in our case, it was not necessary to diagnose the FHHNC patient with macular coloboma, since the diagnosis of ocular damage had been already accurately established by the OCT. PMID:27853022

  18. [Role of immunological factors in peripheral vitreo-chorioretinal dystrophies and macular ruptures of the retina].

    PubMed

    Balashova, L M; Saksonova, E O; Zaĭtseva, N S; Slepova, O S; Teplinskaia, L E; Il'nitskiĭ, V V; Grishin, V L

    1995-01-01

    The authors analyze the results of clinical and immunological examinations of patients with peripheral vitreo-chorioretinal dystrophies (PVCRD) and macular ruptures of the retina. No antibodies to S-AG were detected in the lacrimal fluid in 87.5% of patients with PVCRD without retinal defects. In patients with PVCRD with retinal defects antibodies to S-AG were detected in 70% of cases. These antibodies were absent in the patients with macular ruptures of the retina. In none of the patients were these antibodies detected in the blood serum. The levels of circulating immune complexes were normal in the patients PVCRD and increased in those with macular ruptures of the retina. These data permit a hypothesis on the development of local autoimmune reactions in PVCRD patients in response to the appearance of AG of the injured tissues.

  19. Autologous Induced Stem-Cell-Derived Retinal Cells for Macular Degeneration.

    PubMed

    Mandai, Michiko; Watanabe, Akira; Kurimoto, Yasuo; Hirami, Yasuhiko; Morinaga, Chikako; Daimon, Takashi; Fujihara, Masashi; Akimaru, Hiroshi; Sakai, Noriko; Shibata, Yumiko; Terada, Motoki; Nomiya, Yui; Tanishima, Shigeki; Nakamura, Masahiro; Kamao, Hiroyuki; Sugita, Sunao; Onishi, Akishi; Ito, Tomoko; Fujita, Kanako; Kawamata, Shin; Go, Masahiro J; Shinohara, Chikara; Hata, Ken-Ichiro; Sawada, Masanori; Yamamoto, Midori; Ohta, Sachiko; Ohara, Yasuo; Yoshida, Kenichi; Kuwahara, Junko; Kitano, Yuko; Amano, Naoki; Umekage, Masafumi; Kitaoka, Fumiyo; Tanaka, Azusa; Okada, Chihiro; Takasu, Naoko; Ogawa, Seishi; Yamanaka, Shinya; Takahashi, Masayo

    2017-03-16

    We assessed the feasibility of transplanting a sheet of retinal pigment epithelial (RPE) cells differentiated from induced pluripotent stem cells (iPSCs) in a patient with neovascular age-related macular degeneration. The iPSCs were generated from skin fibroblasts obtained from two patients with advanced neovascular age-related macular degeneration and were differentiated into RPE cells. The RPE cells and the iPSCs from which they were derived were subject to extensive testing. A surgery that included the removal of the neovascular membrane and transplantation of the autologous iPSC-derived RPE cell sheet under the retina was performed in one of the patients. At 1 year after surgery, the transplanted sheet remained intact, best corrected visual acuity had not improved or worsened, and cystoid macular edema was present. (Funded by Highway Program for Realization of Regenerative Medicine and others; University Hospital Medical Information Network Clinical Trials Registry [UMIN-CTR] number, UMIN000011929 .).

  20. 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

  1. Genetics of immunological and inflammatory components in age-related macular degeneration.

    PubMed

    Tuo, Jingsheng; Grob, Seanna; Zhang, Kang; Chan, Chi-Chao

    2012-02-01

    Age-related macular degeneration (AMD), affecting 30 to 50 million elder individuals worldwide, is a disease affecting the macular retina and choroid that can lead to irreversible central vision loss and blindness. Recent findings support a role for immunologic processes in AMD pathogenesis, including generation of inflammatory related molecules in the Bruch's membrane, recruitment of macrophages, complement activation, microglial activation and accumulation in the macular lesions. Pro-inflammatory effects of chronic inflammation and oxidative stress can result in abnormal retinal pigment epithelium, photoreceptor atrophy and choroidal neovascularization. The associations of immunological and inflammatory genes, in particular the genes related to innate immunity with AMD support the involvement of various immunological pathways in the AMD pathogenesis. We review the literature on the involvements of inflammatory genes in AMD, highlight recent genetic discoveries, and discuss the potential application of such knowledge in the management of patients with AMD.

  2. Utility of optical coherence tomography in a case of bilateral congenital macular coloboma.

    PubMed

    Muñoz de Escalona Rojas, José Enrique; Quereda Castañeda, Aurora; García García, Olga

    2016-09-01

    Macular coloboma is a congenital defect of the retina and choroid in the macular region. It may appear due to an intrauterine inflammation or a developmental abnormality. Familial hypomagnesemia with hypercalciuria and nephrocalcinosis (FHHNC) is a result of malformation of the renal tubule. Its combination with ocular manifestations may be genetic, specifically in case of claudin-19 (CLDN-19) gene mutations. The combination of FHHNC and ocular manifestations is not always present in these patients. Optical coherence tomography (OCT) helps us diagnose this condition by allowing us to evaluate and confirm the absence of retina layers without histological examination. Although genetic testing is necessary to diagnose mutational alterations of the CLDN-19 gene, in our case, it was not necessary to diagnose the FHHNC patient with macular coloboma, since the diagnosis of ocular damage had been already accurately established by the OCT.

  3. Costs and Quality of Life in Diabetic Macular Edema: Canadian Burden of Diabetic Macular Edema Observational Study (C-REALITY)

    PubMed Central

    Gonder, John R.; Walker, Valery M.; Barbeau, Martin; Zaour, Nancy; Zachau, Bryan H.; Hartje, James R.; Li, Ruihong

    2014-01-01

    Purpose. To characterize the economic and quality of life burden of diabetic macular edema (DME) in Canadian patients. Patients and Methods. 145 patients with DME were followed for 6 months with monthly telephone interviews and medical chart reviews at months 0, 3, and 6. Visual acuity in the worst-seeing eye was assessed at months 0 and 6. DME-related healthcare costs were determined over 6 months, and vision-related (National Eye Institute Visual Functioning Questionnaire) and generic (EQ-5D) quality of life was assessed at months 0, 3, and 6. Results. Mean age of patients was 63.7 years: 52% were male and 72% had bilateral DME. At baseline, visual acuity was categorized as normal/mild loss for 63.4% of patients, moderate loss for 10.4%, and severe loss/nearly blind for 26.2%. Mean 6-month DME-related costs/patient were as follows: all patients (n = 135), $2,092; normal/mild loss (n = 88), $1,776; moderate loss (n = 13), $1,845; and severe loss/nearly blind (n = 34), $3,007. Composite scores for vision-related quality of life declined with increasing visual acuity loss; generic quality of life scores were highest for moderate loss and lowest for severe loss/nearly blind. Conclusions. DME-related costs in the Canadian healthcare system are substantial. Costs increased and vision-related quality of life declined with increasing visual acuity severity. PMID:24795818

  4. Relationship between macular thickness measurement and signal strength using Stratus optical coherence tomography

    PubMed Central

    Segal, Ori; Shapira, Yinon; Gershoni, Assaf; Vainer, Igor; Nemet, Arie Y; Geffen, Noa; Mimouni, Michael

    2016-01-01

    Purpose To examine the relationship between signal strength and macular thickness as measured by Stratus optical coherence tomography (OCT)’s fast macular thickness protocol in healthy subjects. Methods In this prospective cross-sectional study 79 eyes of 42 healthy subjects were enrolled. The age, gender, and eye (right vs left) of each subject were recorded. The Stratus OCT fast macular thickness scan protocol was used and the macular thickness was measured with retinal thickness map analysis. Each eye was imaged at least six times to acquire images with signal strengths of 4, 5, 6, 7, 8, and 9 out of 10 via adjustment of the focusing knob. The OCT parameters included in the analysis were thickness in the central 1 mm and in the different quadrants in the 3-mm area. Results Overall 79 eyes of 42 patients with a mean age of 38.4±12.4 were included. There was no significant difference between the signal strength measurements obtained with different signal strengths in the central thickness (P=0.20). In the superior, nasal, inferior, and temporal quadrants, a signal strength of 8 demonstrated up to 3 µm thicker measurements than a signal strength of 5 (P<0.05). In general linear regression analysis, after accounting for age and gender, signal strength did not remain a significant predictor of thickness in any quadrant. Conclusions When using fast map macular measurements, a signal strength of 5 is clinically as efficient as a signal strength of 8 in measuring macular thickness in all quadrants. Insisting on higher signal strength may not be necessary. PMID:27956823

  5. Aphakic cystoid macular edema and the operating microscope: is there a connection?

    PubMed Central

    Iliff, W J

    1985-01-01

    The literature documenting the phototoxic effect of relatively low intensity light on the retina and the suggestions by several authors that this might influence the development of cystoid macular edema in the aphakic and pseudophakic patient is reviewed. In particular, the possibility that the operating microscope may be a factor has been emphasized. A study is presented, designed to investigate the possibility that the operating microscope is a factor important in the development of cystoid macular edema. No correlation was found. The need for further investigation into other phototoxic effects from the light of the operating microscope is stressed. PMID:3832535

  6. Unilateral hemorrhagic macular infarction associated with marijuana, alcohol and antiepileptic drug intake.

    PubMed

    Aktaş, Serdar; Tetikoğlu, Mehmet; İnan, Sibel; Aktaş, Hatice; Özcura, Fatih

    2017-03-01

    A 55-year-old male presented with a complaint of a painless and sudden loss of vision in the right eye. Fundus photography revealed loss of transparency and edema in the central macular region. Optical coherence tomography showed increased reflectivity and diffused swelling in the inner retinal layers. Fluorescein angiography revealed a large area of capillary non-perfusion with a pronounced hypofluorescent area with distinct borders. To our knowledge, this is the first report of a hemorrhagic macular infarction associated with marijuana and pregabalin misuse.

  7. Macular ischemia after intravitreal amikacin on patient with intraocular foreign body.

    PubMed

    Kartasasmita, Arief; Mona, Susi; Iskandar, Erwin; Sovani, Iwan; Panggabean, Djonggi

    2017-01-01

    Background: Although still used in third world countries, amikacin has a harmful effect to be used intravitreally. Purpose: To report macular ischemia after an intravitreal injection of amikacin Methods: A case report regarding a traumatized eye of a 26-year-old man that was injected intravitreally with amikacin due to intraocular foreign body endophthalmitis Results: Angiography and OCT show macular ischemia due to amikacin toxicity. Conclusion: The case reported here is to alert about the potential harmful effect of intravitreally injected amikacin despite its role as an accepted regimen for endohthalmitis cases.

  8. Macular ischemia after intravitreal amikacin on patient with intraocular foreign body

    PubMed Central

    Kartasasmita, Arief; Mona, Susi; Iskandar, Erwin; Sovani, Iwan; Panggabean, Djonggi

    2017-01-01

    Background: Although still used in third world countries, amikacin has a harmful effect to be used intravitreally. Purpose: To report macular ischemia after an intravitreal injection of amikacin Methods: A case report regarding a traumatized eye of a 26-year-old man that was injected intravitreally with amikacin due to intraocular foreign body endophthalmitis Results: Angiography and OCT show macular ischemia due to amikacin toxicity. Conclusion: The case reported here is to alert about the potential harmful effect of intravitreally injected amikacin despite its role as an accepted regimen for endohthalmitis cases.

  9. Macular exanthema in a child with rotavirus gastroenteritis: a case report.

    PubMed

    Zulfikar Akelma, Ahmet; Nevzat Cizmeci, Mehmet; Mete, Emin; Dilara Malli, Dilsad; Erpolat, Seval; Mujgan Sonmez, Fatma

    2014-04-01

    Apart from gastroenteritis, rotavirus has been rarely implicated with some cutaneous disorders such as generalized maculo-papular exanthema, infantile acute hemorrhagic edema and Gianotti-Crosti syndrome. We report a 30-month old toddler boy who developed erythematous macular skin eruptions during the course of rotavirus gastroenteritis. To our knowledge, this is the first case in the literature reporting rotavirus-related macular erythematous lesions in a pediatric patient. We therefore would like to share our experience, to keep ro-tavirus infection in the differential diagnosis of children with gastroenteritis and erythematous eruption.

  10. Comparative Effectiveness of Three Prophylactic Strategies to Prevent Clinical Macular Edema Following Phacoemulsification Surgery

    PubMed Central

    Shorstein, Neal H.; Liu, Liyan; Waxman, Michael D.; Herrinton, Lisa J.

    2015-01-01

    PURPOSE To study the relationship of chemoprophylaxis and other factors on the occurrence of acute, clinical postoperative macular edema. DESIGN Retrospective cohort study. The drug regimens consisted of postoperative topical prednisolone acetate (PA) alone or with nonsteroidal anti-inflammatory drug (PA+NSAID) or intraoperative subconjunctival injection of 2 mg triamcinolone acetonide (TA) alone. PARTICIPANTS Patients undergoing phacoemulsification at Kaiser Permanente, Diablo Service Area, Northern California, 2007–2013. METHODS Incident macular edema diagnoses recorded 5–120 days after phacoemulsification, with visual acuity 20/40 or worse and evidence of macular thickening by optical coherence tomography were identified. Odds ratios (OR) and 95% confidence intervals (95% CI) were obtained from logistic regression analysis, conditioned on the surgeon and adjusted for year, patient age and race, diabetic retinopathy, other ocular comorbidities, systemic comorbidity and posterior capsular rupture. MAIN OUTCOME MEASURES Incident rates of acute, clinical, postoperative macular edema. RESULTS We confirmed 118 cases among 16,070 cataract surgeries (incidence, 0.73%). Compared with PA alone, the OR for the relationship of macular edema with PA+NSAID was 0.45 (95% CI, 0.21–0.95) and for TA injection was 1.21 (95% CI, 0.48–3.06). The frequency of intraocular pressure spikes ≥30 mm Hg between postoperative days 16 – 45 was 0.6% in the topical PA group, 0.3% for topical PA+NSAID (p=0.13) and 0.8% for TA (p=0.52). African-American race was associated with risk of macular edema (OR, 2.86; 95% CI, 1.41–5.79). CONCLUSIONS Adding prophylactic NSAID to PA was associated with a reduced risk of macular edema with visual acuity 20/40 or worse. Risk and safety of TA injection was similar to PA alone. Further research is needed on the prognostic significance of postoperative macular edema, the role of prophylaxis, risk in African-Americans, and the effectiveness of

  11. 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

  12. Magnetic fields around black holes

    NASA Astrophysics Data System (ADS)

    Garofalo, David A. G.

    Active Galactic Nuclei are the most powerful long-lived objects in the universe. They are thought to harbor supermassive black holes that range from 1 million solar masses to 1000 times that value and possibly greater. Theory and observation are converging on a model for these objects that involves the conversion of gravitational potential energy of accreting gas to radiation as well as Poynting flux produced by the interaction of the rotating spacetime and the electromagnetic fields originating in the ionized accretion flow. The presence of black holes in astrophysics is taking center stage, with the output from AGN in various forms such as winds and jets influencing the formation and evolution of the host galaxy. This dissertation addresses some of the basic unanswered questions that plague our current understanding of how rotating black holes interact with their surrounding magnetized accretion disks to produce the enormous observed energy. Two magnetic configurations are examined. The first involves magnetic fields connecting the black hole with the inner accretion disk and the other involves large scale magnetic fields threading the disk and the hole. We study the effects of the former type by establishing the consequences that magnetic torques between the black hole and the inner accretion disk have on the energy dissipation profile. We attempt a plausible explanation to the observed "Deep Minimum" state in the Seyfert galaxy MCG-6- 30-15. For the latter type of magnetic geometry, we study the effects of the strength of the magnetic field threading the black hole within the context of the cherished Blandford & Znajek mechanism for black hole spin energy extraction. We begin by addressing the problem in the non-relativistic regime where we find that the black hole-threading magnetic field is stronger for greater disk thickness, larger magnetic Prandtl number, and for a larger accretion disk. We then study the problem in full relativity where we show that our

  13. 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.

  14. Prisons of Light - Black Holes

    NASA Astrophysics Data System (ADS)

    Ferguson, Kitty

    1998-05-01

    In this jargon-free review of one of the most fascinating topics in modern science, acclaimed science writer Kitty Ferguson examines the discovery of black holes, their nature, and what they can teach us about the mysteries of the universe. In search of the answers, we trace a star from its birth to its death throes, take a hypothetical journey to the border of a black hole and beyond, spend time with some of the world's leading theoretical physicists and astronomers, and take a whimsical look at some of the wild ideas black holes have inspired. Prisons of Light--Black Holes is comprehensive and detailed. Yet Kitty Ferguson's lightness of touch and down-to-earth analogies set this book apart from all others on black holes and make it a wonderfully stimulating and entertaining read.

  15. Numerical Simulation of Black Holes

    NASA Astrophysics Data System (ADS)

    Teukolsky, Saul

    2003-04-01

    Einstein's equations of general relativity are prime candidates for numerical solution on supercomputers. There is some urgency in being able to carry out such simulations: Large-scale gravitational wave detectors are now coming on line, and the most important expected signals cannot be predicted except numerically. Problems involving black holes are perhaps the most interesting, yet also particularly challenging computationally. One difficulty is that inside a black hole there is a physical singularity that cannot be part of the computational domain. A second difficulty is the disparity in length scales between the size of the black hole and the wavelength of the gravitational radiation emitted. A third difficulty is that all existing methods of evolving black holes in three spatial dimensions are plagued by instabilities that prohibit long-term evolution. I will describe the ideas that are being introduced in numerical relativity to deal with these problems, and discuss the results of recent calculations of black hole collisions.

  16. 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.

  17. 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

  18. Black hole final state conspiracies

    NASA Astrophysics Data System (ADS)

    McInnes, Brett

    2009-01-01

    The principle that unitarity must be preserved in all processes, no matter how exotic, has led to deep insights into boundary conditions in cosmology and black hole theory. In the case of black hole evaporation, Horowitz and Maldacena were led to propose that unitarity preservation can be understood in terms of a restriction imposed on the wave function at the singularity. Gottesman and Preskill showed that this natural idea only works if one postulates the presence of “conspiracies” between systems just inside the event horizon and states at much later times, near the singularity. We argue that some AdS black holes have unusual internal thermodynamics, and that this may permit the required “conspiracies” if real black holes are described by some kind of sum over all AdS black holes having the same entropy.

  19. Macular pigment spatial distribution effects on glare disability

    PubMed Central

    Putnam, Christopher M.; Bassi, Carl J.

    2015-01-01

    Purpose This project explored the relationship of the macular pigment optical density (MPOD) spatial profile with measures of glare disability (GD) across the macula. Methods A novel device was used to measure MPOD across the central 16° of retina along four radii using customized heterochromatic flicker photometry (cHFP)at eccentricities of 0°, 2°, 4°, 6° and 8°. MPOD was measured as discrete and integrated values at all measured retinal loci. GD was calculated as a difference in contrast sensitivity (CS) between no glare and glare conditions using identical stimuli presented at the same eccentricities. GD was defined as [(CSNo Glare − CSGlare)/CSNo Glare] in order to isolate the glare attenuation effects of MPOD by controlling for CS variability among the subject sample. Correlations of the discrete and integrated MPOD with GD were compared. Results The cHFP identified reliable MPOD spatial distribution maps demonstrating a 1st-order exponential decay as a function of increasing eccentricity. There was a significant negative correlation between both measures of foveal MPOD and GD using 6 cycles per degree (cpd) and 9 cpd stimuli. Significant correlations were found between corresponding parafoveal MPOD measures and GD at 2 and 4° of eccentricity using 9 cpd stimuli with greater MPOD associated with less glare disability. Conclusions These results are consistent with the glare attenuation effects of MP at higher spatial frequencies and support the hypothesis that discrete and integrated measures of MPOD have similar correlations with glare attenuation effects across the macula. Additionally, peak foveal MPOD appears to influence GD across the macula. PMID:25697374

  20. The burden of age-related macular degeneration.

    PubMed

    Schmier, Jordana K; Jones, Mechelle L; Halpern, Michael T

    2006-01-01

    As age-related macular degeneration (AMD) becomes more prevalent as a result of longer life expectancy and the number of elderly people worldwide, it will become increasingly important to understand its potential health and economic impact for appropriate healthcare planning. This review identified published literature on costs and resource use associated with AMD. Despite the increasing prevalence of AMD, the worldwide burden of illness is unknown. Several studies of direct medical costs, both those associated with ophthalmic care and those associated with other care, have been conducted and have identified increased medical care associated with AMD. Direct non-medical costs include the cost for vision aids; while these costs may be substantial, they are difficult to quantify as no comprehensive sources track the distribution or use of vision aids. Because AMD is uncommon among people of working age, there is less concern regarding the impact of indirect (workplace) costs among AMD patients. However, indirect costs are incurred by caregivers who leave the workforce early or change their work patterns in order to provide assistance to AMD patients; the magnitude of caregiver-related costs is unknown. The cost effectiveness of some interventions for AMD has been explored. Supplementation with zinc and antioxidants for non-exudative (dry) AMD has been shown to result in an acceptable cost per QALY and is considered cost effective. Studies suggest that laser photocoagulation is cost effective but that photodynamic therapy with verteporfin appears to be cost effective only among patients with good visual acuity at baseline or when models extend longer than 5 years. Further research is needed to integrate the information on various components of AMD-related costs into a comprehensive burden of illness estimate and to evaluate basic utility assumptions in existing models.

  1. [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.

  2. 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

  3. Nutritional Modulation of Age-Related Macular Degeneration

    PubMed Central

    Weikel, Karen A; Taylor, Allen

    2012-01-01

    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 with AMD are in excess of $340 billion US (American-Health-Assistance-Foundation, 2012). The majority of AMD patients in the United States are not eligible for clinical treatments (Biarnes et al., 2011; Klein et al., 2011). Preventive interventions through dietary modulation are attractive strategies because many studies suggest a benefit of micro and macronutrients with respect to AMD, as well as other age-related debilities, and with few, if any, adverse effects (Chiu, 2011). Preservation of vision would enhance quality of life for millions of elderly people, and alleviate the personal and public health financial burden of AMD (Frick et al., 2007; Wood et al., 2011). Observational studies indicate that maintaining adequate levels of omega-3 fatty acids (i.e. with 2 servings/wk of fish) or a low glycemic index diet may be particularly beneficial for early AMD and that higher levels of carotenoids may be protective, most probably, against neovascular AMD. Intervention trials are needed to better understand the full effect of these nutrients and/or combinations of nutrients on retinal health. Analyses that describe effects of a nutrient on onset and/or progress of AMD are valuable because they indicate the value of a nutrient to arrest AMD at the early stages. This comprehensive summary provides essential information about the value of nutrients with regard to diminishing risk for onset or progress of AMD and can serve as a guide until data from ongoing intervention trials are available. PMID:22503690

  4. 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.

  5. 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

  6. 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.

  7. Age related macular degeneration and drusen: neuroinflammation in the retina.

    PubMed

    Buschini, Elisa; Piras, Antonio; Nuzzi, Raffaele; Vercelli, Alessandro

    2011-09-15

    Inflammation protects from dangerous stimuli, restoring normal tissue homeostasis. Inflammatory response in the nervous system ("neuroinflammation") has distinct features, which are shared in several diseases. The retina is an immune-privileged site, and the tight balance of immune reaction can be disrupted and lead to age-related macular disease (AMD) and to its peculiar sign, the druse. Excessive activation of inflammatory and immunological cascade with subsequent induction of damage, persistent activation of resident immune cells, accumulation of byproducts that exceeds the normal capacity of clearance giving origin to a chronic local inflammation, alterations in the activation of the complement system, infiltration of macrophages, T-lymphocytes and mast-cells from the bloodstream, participate in the mechanisms which originate the drusen. In addition, aging of the retina and AMD involve also para-inflammation, by which immune cells react to persistent stressful stimuli generating low-grade inflammation, aimed at restoring function and maintaining tissue homeostasis by varying the set point in relation to the new altered conditions. This mechanism is also seen in the normal aging retina, but, in the presence of noxious stimuli as in AMD, it can become chronic and have an adverse outcome. Finally, autophagy may provide new insights to understand AMD pathology, due to its contribution in the removal of defective proteins. Therefore, the AMD retina can represent a valuable model to study neuroinflammation, its mechanisms and therapy in a restricted and controllable environment. Targeting these pathways could represent a new way to treat and prevent both exudative and dry forms of AMD.

  8. Systemic complement activation in age-related macular degeneration.

    PubMed

    Scholl, Hendrik P N; Charbel Issa, Peter; Walier, Maja; Janzer, Stefanie; Pollok-Kopp, Beatrix; Börncke, Florian; Fritsche, Lars G; Chong, Ngaihang V; Fimmers, Rolf; Wienker, Thomas; Holz, Frank G; Weber, Bernhard H F; Oppermann, Martin

    2008-07-02

    Dysregulation of the alternative pathway (AP) of complement cascade has been implicated in the pathogenesis of age-related macular degeneration (AMD), the leading cause of blindness in the elderly. To further test the hypothesis that defective control of complement activation underlies AMD, parameters of complement activation in blood plasma were determined together with disease-associated genetic markers in AMD patients. Plasma concentrations of activation products C3d, Ba, C3a, C5a, SC5b-9, substrate proteins C3, C4, factor B and regulators factor H and factor D were quantified in patients (n = 112) and controls (n = 67). Subjects were analyzed for single nucleotide polymorphisms in factor H (CFH), factor B-C2 (BF-C2) and complement C3 (C3) genes which were previously found to be associated with AMD. All activation products, especially markers of chronic complement activation Ba and C3d (p<0.001), were significantly elevated in AMD patients compared to controls. Similar alterations were observed in factor D, but not in C3, C4 or factor H. Logistic regression analysis revealed better discriminative accuracy of a model that is based only on complement activation markers Ba, C3d and factor D compared to a model based on genetic markers of the complement system within our study population. In both the controls' and AMD patients' group, the protein markers of complement activation were correlated with CFH haplotypes.This study is the first to show systemic complement activation in AMD patients. This suggests that AMD is a systemic disease with local disease manifestation at the ageing macula. Furthermore, the data provide evidence for an association of systemic activation of the alternative complement pathway with genetic variants of CFH that were previously linked to AMD susceptibility.

  9. Inflammation and its role in age-related macular degeneration.

    PubMed

    Kauppinen, Anu; Paterno, Jussi J; Blasiak, Janusz; Salminen, Antero; Kaarniranta, Kai

    2016-05-01

    Inflammation is a cellular response to factors that challenge the homeostasis of cells and tissues. Cell-associated and soluble pattern-recognition receptors, e.g. Toll-like receptors, inflammasome receptors, and complement components initiate complex cellular cascades by recognizing or sensing different pathogen and damage-associated molecular patterns, respectively. Cytokines and chemokines represent alarm messages for leukocytes and once activated, these cells travel long distances to targeted inflamed tissues. Although it is a crucial survival mechanism, prolonged inflammation is detrimental and participates in numerous chronic age-related diseases. This article will review the onset of inflammation and link its functions to the pathogenesis of age-related macular degeneration (AMD), which is the leading cause of severe vision loss in aged individuals in the developed countries. In this progressive disease, degeneration of the retinal pigment epithelium (RPE) results in the death of photoreceptors, leading to a loss of central vision. The RPE is prone to oxidative stress, a factor that together with deteriorating functionality, e.g. decreased intracellular recycling and degradation due to attenuated heterophagy/autophagy, induces inflammation. In the early phases, accumulation of intracellular lipofuscin in the RPE and extracellular drusen between RPE cells and Bruch's membrane can be clinically detected. Subsequently, in dry (atrophic) AMD there is geographic atrophy with discrete areas of RPE loss whereas in the wet (exudative) form there is neovascularization penetrating from the choroid to retinal layers. Elevations in levels of local and systemic biomarkers indicate that chronic inflammation is involved in the pathogenesis of both disease forms.

  10. Swept Source OCT Angiography of Neovascular Macular Telangiectasia Type 2

    PubMed Central

    Zhang, Qinqin; Wang, Ruikang K.; Chen, Chieh-Li; Legarreta, Andrew D.; Durbin, Mary K.; An, Lin; Sharma, Utkarsh; Stetson, Paul F.; Legarreta, John E.; Roisman, Luiz; Gregori, Giovanni; Rosenfeld, Philip J.

    2015-01-01

    Objective To image subretinal neovascularization in proliferative macular telangiectasia type 2 (MacTel2) using swept source optical coherence tomography based microangiography (OMAG). Study Design Patients with MacTel2 were enrolled in a prospective, observational study known as the MacTel Project and evaluated using a high-speed 1050nm swept-source OCT (SS-OCT) prototype system. The OMAG algorithm generated en face flow images from three retinal layers, as well as the region bounded by the outer retina and Bruch’s membrane, the choriocapillaris, and the remaining choroidal vasculature. The en face OMAG images were compared to images from fluorescein angiography (FA) and indocyanine green angiography (ICGA). Results Three eyes with neovascular MacTel2 were imaged. The neovascularization was best identified from the en face OMAG images that included a layer between the outer retinal boundary and Bruch’s membrane. OMAG images identified these abnormal vessels better than FA and were comparable to the images obtained using ICGA. In all three cases, OMAG identified choroidal vessels communicating with the neovascularization, and these choroidal vessels were evident in the two cases with ICGA imaging. In one case, monthly injections of bevacizumab reduced the microvascular complexity of the neovascularization, as well as the telangiectatic changes within the retinal microvasculature. In another case, less frequent bevacizumab therapy was associated with growth of the subretinal neovascular complex. Conclusions OMAG imaging provided detailed, depth-resolved information about subretinal neovascularization in MacTel2 eyes demonstrating superiority to FA imaging and similarities to ICGA imaging for documenting the retinal microvascular changes, the size and extent of the neovascular complex, the communications between the neovascular complex and the choroidal circulation, and the response to monthly bevacizumab therapy. PMID:26457402

  11. Wet age related macular degeneration management and follow-up.

    PubMed

    Alexandru, Malciolu Radu; Alexandra, Nica Maria

    2016-01-01

    Age-related macular degeneration (AMD) is referred to as the leading cause of irreversible visual loss in developed countries, with a profound effect on the quality of life. The neovascular form of AMD is characterized by the formation of subretinal choroidal neovascularization, leading to sudden and severe visual loss. Research has identified the vascular endothelial growth factor (VEGF) as an important pathophysiological component in neovascular AMD and its intraocular inhibition as one of the most efficient therapies in medicine. The introduction of anti-VEGF as a standard treatment in wet AMD has led to a great improvement in the prognosis of patients, allowing recovery and maintenance of visual function in the vast majority of cases. However, the therapeutic benefit is accompanied by a difficulty in maintaining the treatment schedule due to the increase in the amount of patients, stress of monthly assessments, as well as the associated economic burden. Therefore, treatment strategies have evolved from fixed monthly dosing, to individualized regimens, aiming for comparable results, with fewer injections. One such protocol is called "pro re nata", or "treat and observe". Patients are given a loading dose of 3 monthly injections, followed by an as-needed decision to treat, based on the worsening of visual acuity, clinical evidence of the disease activity on fundoscopy, or OCT evidence of retinal thickening in the presence of intra or subretinal fluid. A different regimen is called "treat and extend", in which the interval between injections is gradually increased, once the disease stabilization is achieved. This paper aims to review the currently available anti-VEGF agents--bevacizumab, ranibizumab, aflibercept, and the aforementioned treatment strategies.

  12. Nutritional modulation of age-related macular degeneration.

    PubMed

    Weikel, Karen A; Chiu, Chung-Jung; Taylor, Allen

    2012-08-01

    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 with AMD are in excess of $340 billion US (American-Health-Assistance-Foundation, 2012). The majority of AMD patients in the United States are not eligible for clinical treatments (Biarnes et al., 2011; Klein et al., 2011). Preventive interventions through dietary modulation are attractive strategies because many studies suggest a benefit of micro- and macronutrients with respect to AMD, as well as other age-related debilities, and with few, if any, adverse effects (Chiu, 2011). Preservation of vision would enhance quality of life for millions of elderly people, and alleviate the personal and public health financial burden of AMD (Frick et al., 2007; Wood et al., 2011). Observational studies indicate that maintaining adequate levels of omega-3 fatty acids (i.e. with 2 servings/week of fish) or a low glycemic index diet may be particularly beneficial for early AMD and that higher levels of carotenoids may be protective, most probably, against neovascular AMD. Intervention trials are needed to better understand the full effect of these nutrients and/or combinations of nutrients on retinal health. Analyses that describe effects of a nutrient on onset and/or progress of AMD are valuable because they indicate the value of a nutrient to arrest AMD at the early stages. This comprehensive summary provides essential information about the value of nutrients with regard to diminishing risk for onset or progress of AMD and can serve as a guide until data from ongoing intervention trials are available.

  13. 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...

  14. Hidden Structures of Black Holes

    NASA Astrophysics Data System (ADS)

    Vercnocke, Bert

    2010-11-01

    This thesis investigates two main topics concerning black holes in extensions of general relativity inspired by string theory. First, the structure of the equations of motion underlying black hole solutions is considered, in theories of D-dimensional gravity coupled to scalars and vectors. For solutions preserving supersymmetry, the equations of motion have a dramatic simplification: they become first-order instead of the second-order equations one would expect. Recently, it was found that this is a feature some non-supersymmetric black hole solutions exhibit as well. We investigate if this holds more generally, by examining what the conditions are to have first-order equations for the scalar fields of non-supersymmetric black holes, that mimic the form of their supersymmetric counterparts. This is illustrated in examples. Second, the structure of black holes themselves is investigated. String theory has been successful in explaining the Bekenstein-Hawking entropy for (mainly supersymmetric) black holes from a microscopic perspective. However, it is not fully established what the interpretation of the corresponding 'microstates' should be in the gravitational description where the black hole picture is valid. There have been recent advances to understand the nature of black hole microstates in the gravity regime, such as the fuzzball proposal. A related idea says that black hole configurations with multiple centers are related to microstates of single-centered black holes. We report on work relating both pictures. As an aside, a relation between violations of causality for certain spacetimes (presence of closed timelike curves in the geometry) and a breakdown of unitarity in the dual conformal field theory is given.

  15. Macular thickness measurements with frequency domain-OCT for quantification of axonal loss in chronic papilledema from pseudotumor cerebri syndrome

    PubMed Central

    Monteiro, M L R; Afonso, C L

    2014-01-01

    Purpose To evaluate the ability of frequency domain-optical coherence tomography (FD-OCT)-measured macular thickness parameters to differentiate between eyes with resolved chronic papilledema and healthy eyes and to evaluate the correlation between FD-OCT measures and visual field (VF) loss on standard automated perimetry (SAP). Methods Fifty-two eyes from 29 patients suffering from pseudotumor cerebri syndrome (PTC) and 62 eyes from 31 normal controls underwent FD-OCT scanning and ophthalmic evaluation including VF with SAP. All patients had previously been submitted to treatment of PTC and had clinically resolved papilledema and stable VF for at least 6 months before the study. Macular and peripapillary retinal nerve fiber layer (RNFL) thickness measurements were determined for both groups. Comparisons were made using Generalized Estimated Equations. Correlations between FD-OCT and VF measurements were verified. Results In eyes with resolved papilledema, the macular thickness parameters corresponding to the inner and outer superior, temporal, inferior and nasal segments, average macular thickness and most RNFL thickness measurements were significantly reduced when compared with controls. The discrimination ability was similar for macular thickness measurements and RNFL thickness measurements. Both sets of OCT measurements correlated well with VF sensitivity loss. Conclusions Eyes with resolved chronic papilledema show a significant reduction in macular thickness, which is well correlated with the severity of VF loss. Macular thickness measurements can potentially be used to estimate and monitor the amount of ganglion cell loss in eyes with papilledema from patients with PTC. PMID:24406417

  16. 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.

  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. Efficacy of single bevacizumab injection as adjuvant therapy to laser photocoagulation in macular edema secondary to branch retinal vein occlusion

    PubMed Central

    Kartasasmita, Arief S; Takarai, Siska; Switania, Astriviani; Enus, Sutarya

    2016-01-01

    Background Macular grid laser photocoagulation remains the standard treatment for macular edema secondary to branch retinal vein occlusion (BRVO). One possible strategy for treating macular edema is to inhibit VEGF activity by competitive binding of VEGF with an anti-VEGF antibody, suggesting the therapy option with bevacizumab. However, multiple injections of anti-VEGF may lead to complications and high cost. Purpose The aim of this study was to evaluate the improvement in visual acuity and central macular thickness after combination therapy of laser photocoagulation with single intravitreal bevacizumab injection in macular edema secondary to BRVO. Methods Nineteen patients with macular edema secondary to BRVO were assigned to either the group of nine patients in combination therapy of laser photocoagulation with intravitreal bevacizumab or the group of ten patients in the laser photocoagulation therapy. Complete ophthalmologic examinations were performed just before the therapy and at 1 month following the therapy. Changes in visual acuity were tested with the logarithm of minimum angle of resolution (logMAR), and central macular thickness was measured by optical coherence tomography (OCT). Results Combination therapy of laser photocoagulation and single intravitreal bevacizumab injection resulted in a significantly better visual acuity compared to laser photocoagulation therapy (0.35 versus 0.13 logMAR; P=0.041) and reduced macular thickness by 120.33 µm versus 71.50 µm (P=0.277), although this difference was not significant. Conclusion Laser photocoagulation combined with a single intravitreal bevacizumab has a substantial effect on increasing visual acuity in macular edema secondary to BRVO. PMID:27826179

  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. 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.