COMPARISON OF RETINAL PATHOLOGY VISUALIZATION IN MULTISPECTRAL SCANNING LASER IMAGING.

PubMed

Meshi, Amit; Lin, Tiezhu; Dans, Kunny; Chen, Kevin C; Amador, Manuel; Hasenstab, Kyle; Muftuoglu, Ilkay Kilic; Nudleman, Eric; Chao, Daniel; Bartsch, Dirk-Uwe; Freeman, William R

2018-03-16

To compare retinal pathology visualization in multispectral scanning laser ophthalmoscope imaging between the Spectralis and Optos devices. This retrospective cross-sectional study included 42 eyes from 30 patients with age-related macular degeneration (19 eyes), diabetic retinopathy (10 eyes), and epiretinal membrane (13 eyes). All patients underwent retinal imaging with a color fundus camera (broad-spectrum white light), the Spectralis HRA-2 system (3-color monochromatic lasers), and the Optos P200 system (2-color monochromatic lasers). The Optos image was cropped to a similar size as the Spectralis image. Seven masked graders marked retinal pathologies in each image within a 5 × 5 grid that included the macula. The average area with detected retinal pathology in all eyes was larger in the Spectralis images compared with Optos images (32.4% larger, P < 0.0001), mainly because of better visualization of epiretinal membrane and retinal hemorrhage. The average detection rate of age-related macular degeneration and diabetic retinopathy pathologies was similar across the three modalities, whereas epiretinal membrane detection rate was significantly higher in the Spectralis images. Spectralis tricolor multispectral scanning laser ophthalmoscope imaging had higher rate of pathology detection primarily because of better epiretinal membrane and retinal hemorrhage visualization compared with Optos bicolor multispectral scanning laser ophthalmoscope imaging.

Accidental human laser retinal injuries from military laser systems

NASA Astrophysics Data System (ADS)

Stuck, Bruce E.; Zwick, Harry; Molchany, Jerome W.; Lund, David J.; Gagliano, Donald A.

1996-04-01

The time course of the ophthalmoscopic and functional consequences of eight human laser accident cases from military laser systems is described. All patients reported subjective vision loss with ophthalmoscopic evidence of retinal alteration ranging from vitreous hemorrhage to retinal burn. Five of the cases involved single or multiple exposures to Q-switched neodymium radiation at close range whereas the other three incidents occur over large ranges. Most exposures were within 5 degrees of the foveola, yet none directly in the foveola. High contrast visual activity improved with time except in the cases with progressive retinal fibrosis between lesion sites or retinal hole formation encroaching the fovea. In one patient the visual acuity recovered from 20/60 at one week to 20/25 in four months with minimal central visual field loss. Most cases showed suppression of high and low spatial frequency contrast sensitivity. Visual field measurements were enlarged relative to ophthalmoscopic lesion size observations. Deep retinal scar formation and retinal traction were evident in two of the three cases with vitreous hemorrhage. In one patient, nerve fiber layer damage to the papillo-macular bundle was clearly evident. Visual performance measured with a pursuit tracking task revealed significant performance loss relative to normal tracking observers even in cases where acuity returned to near normal levels. These functional and performance deficits may reflect secondary effects of parafoveal laser injury.

Variational mode decomposition based approach for accurate classification of color fundus images with hemorrhages

NASA Astrophysics Data System (ADS)

Lahmiri, Salim; Shmuel, Amir

2017-11-01

Diabetic retinopathy is a disease that can cause a loss of vision. An early and accurate diagnosis helps to improve treatment of the disease and prognosis. One of the earliest characteristics of diabetic retinopathy is the appearance of retinal hemorrhages. The purpose of this study is to design a fully automated system for the detection of hemorrhages in a retinal image. In the first stage of our proposed system, a retinal image is processed with variational mode decomposition (VMD) to obtain the first variational mode, which captures the high frequency components of the original image. In the second stage, four texture descriptors are extracted from the first variational mode. Finally, a classifier trained with all computed texture descriptors is used to distinguish between images of healthy and unhealthy retinas with hemorrhages. Experimental results showed evidence of the effectiveness of the proposed system for detection of hemorrhages in the retina, since a perfect detection rate was achieved. Our proposed system for detecting diabetic retinopathy is simple and easy to implement. It requires only short processing time, and it yields higher accuracy in comparison with previously proposed methods for detecting diabetic retinopathy.

Surgical management of retinal diseases: proliferative diabetic retinopathy and traction retinal detachment.

PubMed

Cruz-Iñigo, Yousef J; Acabá, Luis A; Berrocal, Maria H

2014-01-01

Current indications for pars plana vitrectomy in patients with proliferative diabetic retinopathy (PDR) include vitreous hemorrhage, tractional retinal detachment (TRD), combined tractional and rhegmatogenous retinal detachment (CTRRD), diabetic macular edema associated with posterior hyaloidal traction, and anterior segment neovascularization with media opacities. This chapter will review the indications, surgical objectives, adjunctive pharmacotherapy, microincision surgical techniques, and outcomes of diabetic vitrectomy for PDR, TRD, and CTRRD. With the availability of new microincision vitrectomy technology, wide-angle microscope viewing systems, and pharmacologic agents, vitrectomy can improve visual acuity and achieve long-term anatomic stability in eyes with severe complications from PDR. © 2014 S. Karger AG, Basel

Potential for autoimmune pathogenesis of Rift Valley Fever virus retinitis.

PubMed

Newman-Gerhardt, Shoshana; Muiruri, Samuel; Muchiri, Eric; Peters, Clarence J; Morrill, John; Lucas, Alexander H; King, Charles H; Kazura, James; LaBeaud, Angelle Desiree

2013-09-01

Rift Valley Fever (RVF) is a significant threat to human health because it can progress to retinitis, encephalitis, and hemorrhagic fever. The timing of onset of Rift Valley Fever virus (RVFV) retinitis suggests an autoimmune origin. To determine whether RVFV retinitis is associated with increased levels of IgG against retinal tissue, we measured and compared levels of IgG against healthy human eye tissue by immunohistochemical analysis. We found that serum samples from RVFV-exposed Kenyans with retinitis (n = 8) were slightly more likely to have antibodies against retinal tissue than control populations, but the correlation was not statistically significant. Further investigation into the possible immune pathogenesis of RVFV retinitis could lead to improved therapies to prevent or treat this severe complication.

Potential for Autoimmune Pathogenesis of Rift Valley Fever Virus Retinitis

PubMed Central

Newman-Gerhardt, Shoshana; Muiruri, Samuel; Muchiri, Eric; Peters, Clarence J.; Morrill, John; Lucas, Alexander H.; King, Charles H.; Kazura, James; LaBeaud, Angelle Desiree

2013-01-01

Rift Valley Fever (RVF) is a significant threat to human health because it can progress to retinitis, encephalitis, and hemorrhagic fever. The timing of onset of Rift Valley Fever virus (RVFV) retinitis suggests an autoimmune origin. To determine whether RVFV retinitis is associated with increased levels of IgG against retinal tissue, we measured and compared levels of IgG against healthy human eye tissue by immunohistochemical analysis. We found that serum samples from RVFV-exposed Kenyans with retinitis (n = 8) were slightly more likely to have antibodies against retinal tissue than control populations, but the correlation was not statistically significant. Further investigation into the possible immune pathogenesis of RVFV retinitis could lead to improved therapies to prevent or treat this severe complication. PMID:23918215

Retinal Changes in Uncomplicated and Severe Plasmodium knowlesi Malaria.

PubMed

Govindasamy, Gayathri; Barber, Bridget E; Ghani, Shuaibah A; William, Timothy; Grigg, Matthew J; Borooah, Shyamanga; Dhillon, Bal; Dondorp, Arjen M; Yeo, Tsin W; Anstey, Nicholas M; Maude, Richard J

2016-05-01

Plasmodium knowlesi causes severe malaria, but its pathogenesis is poorly understood. Retinal changes provide insights into falciparum malaria pathogenesis but have not been studied in knowlesi malaria. An observational study was conducted in Malaysian adults hospitalized with severe (n = 20) and nonsevere (n = 24) knowlesi malaria using indirect ophthalmoscopy (n = 44) and fundus photography (n = 29). The patients' median age was 44 years (range, 18-74 years). No coma or deaths occurred. Photography detected retinal changes in 11 of 12 patients (92%) with severe and 14 of 17 (82%) with nonsevere knowlesi malaria. Nonspecific retinal whitening occurred in 3 (35%) and 5 (29%) patients with severe and nonsevere disease, respectively; hemorrhages in 2 (17%) and 3 (18%); loss of retinal pigment epithelium in 1 (8%) and 4 (24%); and drusen in 9 (71%) and 12 (75%). All changes were mild, with no significant differences between severe and nonsevere disease. Patients with retinal hemorrhages had lower platelet counts than those without (median, 22 vs 43 × 10(9)/L; P= .04). The paucity of specific retinal findings associated with disease severity in knowlesi malaria contrasts with the retinopathy of severe adult falciparum malaria with and without coma, suggesting that falciparum-like microvascular sequestration in the brain is not a major component in severe knowlesi malaria pathogenesis. © The Author 2015. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Vitreous hemorrhage and Rhegmatogenous retinal detachment that developed after botulinum toxin injection to the extraocular muscle: case report.

PubMed

Lee, Dong Hyun; Han, Jinu; Han, Sueng-Han; Lee, Sung Chul; Kim, Min

2017-12-13

The authors report a case of a rare complication that occurred after botulinum toxin injection to the extraocular muscle, which was easily overlooked and successfully corrected by surgery. A 34-year-old female patient visited our clinic for diplopia and ocular motility disorder after removal of an epidermoid tumor of the brain. At her initial visit, her best-corrected visual acuity (BCVA) was 20/20 for both eyes. An alternate cover test showed 45 prism-diopter esotropia and 3 prism-diopter hypertropia in the right eye. Following 6 months of observation, the deviation of the strabismus did not improve, and botulinum toxin was injected into the right medial rectus (RMR). After 6 days, she visited our clinic with decreased visual acuity of her right eye. The BCVA was found to be 20/50 for her right eye. Funduscopic examination presented a retinal tear inferonasal to the optic disc with preretinal hemorrhage. Subretinal fluid nasal to the fovea was seen on optical coherence tomography (OCT). Barrier laser photocoagulation was done around the retinal tear; however, her visual acuity continued to decrease, and vitreous hemorrhage and subretinal fluid at the lesion did not improve. In addition, a newly developed epiretinal membrane was seen on OCT. An alternate cover test presented 30 prism-diopter right esotropia. 19 weeks after RMR botulinum toxin injection, she received pars plana vitrectomy, membranectomy, endolaser barrier photocoagulation, and intravitreal bevacizumab (Avastin®) injection. After 4 months, her visual acuity improved to 20/20, and only 4 prism-diopter of right hypertropia and 3 prism-diopter of exotropia were noted. Vitreous opacity and the epiretinal membrane were completely removed, as confirmed by funduscopic and examination. Sudden loss of vision after injection of botulinum toxin into the extraocular muscle may suggest a serious complication, and a prompt, thorough ophthalmic examination should be performed. If improvements are not observed

Combined branch retinal vein and artery occlusion in toxoplasmosis.

PubMed

Aggio, Fabio Bom; Novelli, Fernando José de; Rosa, Evandro Luis; Nobrega, Mário Junqueira

2016-01-01

A 22-year-old man complained of low visual acuity and pain in his left eye for five days. His ophthalmological examination revealed 2+ anterior chamber reaction and a white, poorly defined retinal lesion at the proximal portion of the inferotemporal vascular arcade. There were retinal hemorrhages in the inferotemporal region extending to the retinal periphery. In addition, venous dilation, increased tortuosity, and ischemic retinal whitening along the inferotemporal vascular arcade were also observed. A proper systemic work-up was performed, and the patient was diagnosed with ocular toxoplasmosis. He was treated with an anti-toxoplasma medication, and his condition slowly improved. Inferior macular inner and middle retinal atrophy could be observed on optical coherence tomography as a sequela of ischemic injury. To our knowledge, this is the first report of combined retinal branch vein and artery occlusion in toxoplasmosis resulting in a striking and unusual macular appearance.

Automated detection of retinal whitening in malarial retinopathy

NASA Astrophysics Data System (ADS)

Joshi, V.; Agurto, C.; Barriga, S.; Nemeth, S.; Soliz, P.; MacCormick, I.; Taylor, T.; Lewallen, S.; Harding, S.

2016-03-01

Cerebral malaria (CM) is a severe neurological complication associated with malarial infection. Malaria affects approximately 200 million people worldwide, and claims 600,000 lives annually, 75% of whom are African children under five years of age. Because most of these mortalities are caused by the high incidence of CM misdiagnosis, there is a need for an accurate diagnostic to confirm the presence of CM. The retinal lesions associated with malarial retinopathy (MR) such as retinal whitening, vessel discoloration, and hemorrhages, are highly specific to CM, and their detection can improve the accuracy of CM diagnosis. This paper will focus on development of an automated method for the detection of retinal whitening which is a unique sign of MR that manifests due to retinal ischemia resulting from CM. We propose to detect the whitening region in retinal color images based on multiple color and textural features. First, we preprocess the image using color and textural features of the CMYK and CIE-XYZ color spaces to minimize camera reflex. Next, we utilize color features of the HSL, CMYK, and CIE-XYZ channels, along with the structural features of difference of Gaussians. A watershed segmentation algorithm is used to assign each image region a probability of being inside the whitening, based on extracted features. The algorithm was applied to a dataset of 54 images (40 with whitening and 14 controls) that resulted in an image-based (binary) classification with an AUC of 0.80. This provides 88% sensitivity at a specificity of 65%. For a clinical application that requires a high specificity setting, the algorithm can be tuned to a specificity of 89% at a sensitivity of 82%. This is the first published method for retinal whitening detection and combining it with the detection methods for vessel discoloration and hemorrhages can further improve the detection accuracy for malarial retinopathy.

Hemorrhagic Retinopathy after Spondylosis Surgery and Seizure.

PubMed

Kord Valeshabad, Ali; Francis, Andrew W; Setlur, Vikram; Chang, Peter; Mieler, William F; Shahidi, Mahnaz

2015-08-01

To report bilateral hemorrhagic retinopathy in an adult female subject after lumbar spinal surgery and seizure. A 38-year-old woman presented with bilateral blurry vision and spots in the visual field. The patient had lumbar spondylosis surgery that was complicated by a dural tear with persistent cerebrospinal fluid leak. Visual symptoms started immediately after witnessed seizure-like activity. At presentation, visual acuity was 20/100 and 20/25 in the right and left eye, respectively. Dilated fundus examination demonstrated bilateral hemorrhagic retinopathy with subhyaloid, intraretinal, and subretinal involvement. At 4-month follow-up, visual acuity improved to 20/60 and 20/20 in the right and left eye, respectively. Dilated fundus examination and fundus photography showed resolution of retinal hemorrhages in both eyes. The first case of bilateral hemorrhagic retinopathy after lumbar spondylosis surgery and witnessed seizure in an adult was reported. Ophthalmic examination may be warranted after episodes of seizure in adults.

Foveal hemorrhage in an eye with foveal hypoplasia associated with albinism.

PubMed

Masuda, Naonori; Hasegawa, Taiji; Yamashita, Mariko; Ogata, Nahoko

2014-01-01

Oculocutaneous albinism is a group of congenital disorders caused by alterations of melanin biosynthesis. We report our findings in a patient with oculocutaneous albinism who presented with foveal hypoplasia and a foveal hemorrhage. A 48-year-old man noted a dark spot in the middle of the visual field of his right eye. He had depigmented skin, white hair, white eyebrows, and white cilia. He also had horizontal nystagmus and depigmented irides. His best-corrected visual acuity was 2/100 with -14.0 diopters in the right eye and 3/100 with -5.0 diopters in the left eye. Ophthalmoscopy showed diffuse depigmentation in both eyes and a foveal hemorrhage in the right eye. Optical coherence tomography showed the absence of a foveal pit in both eyes and a subretinal hyperreflective lesion corresponding to the foveal hemorrhage in the right eye. Fluorescein angiography showed that the retinal and choroidal vessels were relatively hypofluorescent because of the lack of a blocking effect of the pigments in the retinal pigment epithelium. Fluorescein angiography and indocyanine green angiography did not show any evidence of choroidal neovascularization in either eye. The foveal hemorrhage in the right eye spontaneously regressed and finally resolved at 3 months after onset. At the final examination, the patient reported that his vision had recovered. A foveal hemorrhage is a rare condition in an eye with foveal hypoplasia associated with albinism. The hemorrhage may be related to high myopia and also to the hypoplasia of the fovea associated with albinism.

Cytomegalovirus retinitis in a patient with proliferative diabetes retinopathy.

PubMed

Takayama, Kei; Ogawa, Manabu; Mochizuki, Manabu; Takeuchi, Masaru

2013-06-01

To report a case of cytomegalovirus (CMV) retinitis in an immunocompetent patient with proliferative diabetic retinopathy (PDR). Case report. A 69-year-old man presented with a 44-year history of diabetes mellitus and 4 years of PDR. Fundus of left eye could not be visualized because of vitreous hemorrhage. Laboratory tests indicated normal immunological status. Yellowish white retinal exudative lesion and whitening inside vascular arcades were observed during vitrectomy. Multiplex PCR using vitreous sample detected CMV DNA at 4.37 × 10(4) copies/mL. CMV retinitis was diagnosed. If atypical findings of PDR are observed, a multiplex PCR test should be performed for further investigation.

Isolated unilateral cytomegalovirus retinitis: a rare long-term complication after pediatric liver transplantation.

PubMed

Squires, James E; Sisk, Robert A; Balistreri, William F; Kohli, Rohit

2013-02-01

To highlight the rare yet devastating complication of CMV retinitis in a minimally immunosuppressed patient eight yr after liver transplantation for biliary atresia. A 22-yr-old female status-post deceased donor liver transplant at age 13 secondary to biliary atresia receiving single agent immunosuppression presented with acute, unilateral, profound decrease in visual acuity. The patient was diagnosed to have acute onset unilateral CMV retinitis. Retinal examination uncovered classical appearance of retinal whitening and retinal hemorrhages with extensive macular involvement. CMV retinitis can occur as a late complication following liver transplantation. Additionally, CMV retinal disease can occur in the absence of laboratory evidence of CMV infection and independent of additional clinical features suggesting CMV disease. Currently, there is no standard of care regarding screening for CMV retinitis, and thus, further research is needed to define the need for potential changes in current clinical practices and post-transplant screening protocols. © 2012 John Wiley & Sons A/S.

Intra- and inter-rater agreement between an ophthalmologist and mid-level ophthalmic personnel to diagnose retinal diseases based on fundus photographs at a primary eye center in Nepal: the Bhaktapur Retina Study.

PubMed

Thapa, Raba; Bajimaya, Sanyam; Bouman, Renske; Paudyal, Govinda; Khanal, Shankar; Tan, Stevie; Thapa, Suman S; van Rens, Ger

2016-07-18

Early detection can reduce irreversible blindness from retinal diseases. This study aims to assess the intra- and inter-rater agreement of retinal pathologies observed on fundus photographs between an ophthalmologist and two-mid level ophthalmic personnel (MLOPs). A population-based, cross-sectional study was conducted among subjects 60 years and above in the Bhaktapur district of Nepal. Fundus photographs of 500 eyes of 500 subjects were assessed. The macula-centered 45-degree photographs were graded twice by one ophthalmologist and two MLOPs. Intra-rater and inter-rater agreements were assessed for the ophthalmologist and the MLOPs. Mean age was 70.22 years ± 6.94 (SD). Retinal pathologies were observed in 55.6 % of photographs (age-related macular degeneration: 34.2 %; diabetic retinopathy: 4.2 %; retinal vein occlusion: 3.8 %). Twelve (2.4 %) fundus pictures were non-gradable. The intra-rater agreement for overall retinal pathologies, retinal hemorrhage, and maculopathy were substantial both for the ophthalmologist as well as for the MLOPs. There was moderate inter-rater agreement between the ophthalmologist and the first MLOP on second rating for overall retinal pathologies, [kappa (k); 95 % CI = 0.59 (0.51-0.66)], retinal hemorrhage [k; 95 % CI = 0.60 (0.41-0.78)], and maculopathy [k; 95 % CI = 0.52 (0.43-0.60)]. Inter-rater agreement between the ophthalmologist and the second MLOP for second rating was moderate for overall retinal pathologies [k; 95 % CI = 0.52 (0.44-0.60)], substantial agreement for retinal hemorrhage [k; 95 % CI = 0. 68 (0.52-0.84)], moderate agreement for maculopathy [k; 95 % CI = 0.59 (0.50-0.67)]. There is moderate agreement between the MLOPs and the ophthalmologist in grading fundus photographs for retinal hemorrhages and maculopathy.

Macular hemorrhages associated with neonatal polycythemia and thrombocytopenia: A case report.

PubMed

Cui, Z; Zhang, Y; Liang, L; Li, Z; Hao, Q

2017-02-01

Thrombocytopenia occurs in 51% of neonates with polycythemia and is independently associated with growth restriction. Increased hematocrit is associated with decreased platelet count. The possibility of a hemorrhage should be noted. A Chinese male newborn presented with elevated hemoglobin and hematocrit levels. The platelet count decreased to 10×10 9 /L during the 1st week after birth and remained abnormal at day 12. Vitreous turbidity of the right eye was detected 2 days later and was suspected of stemming from endophthalmitis or ocular inflammation. Two weeks later, vitreous turbidity decreased and a macular hemorrhage became visible. Optical coherence tomography confirmed the diagnosis of a retinal hemorrhage. Thrombocytopenia associated with polycythemia can induce a vitreous hemorrhage, which may be confused with ocular infection or inflammation. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Bilateral intraocular calcification in necrotizing cytomegalovirus retinitis.

PubMed

Tuncer, Samuray; Oray, Merih; Yildirim, Yeliz; Camcioglu, Yildiz; Tugal-Tutkun, Ilknur

2014-10-01

We report a unique case of bilateral intraocular calcification due to necrotizing cytomegalovirus (CMV) retinitis associated with congenital CMV infection. A 7-month-old boy with a history of congenital CMV infection showed bilateral intraocular calcific plaques on computed tomography (CT) and ultrasonography. We reviewed the patient's medical files for the purpose of this report. The patient had a prior medical history of hospitalization for fever and swelling in the neck at 3 months of age. Systemic findings (anemia, neutropenia, hepatosplenomegaly, and reactive lymphadenomegaly) in association with a low CD4 count, high blood CMV viral load, and positivity for urine CMV DNA by polymerase chain reaction led to the diagnosis of bone marrow suppression and congenital CMV infection. At 7 months, he developed horizontal nystagmus and bilateral leukocoria over 20 days. Cranial CT and ultrasonography revealed bilateral intraocular calcific plaques and the patient was referred to rule out retinoblastoma. Fundoscopy was consistent with bilateral hemorrhagic, necrotizing CMV retinitis. Significant resolution of the retinal infiltrations occurred 2 weeks after initiation of systemic treatment with ganciclovir. Intraocular calcification may be a sign of active CMV retinitis. To our knowledge this is the first report of bilateral intraocular calcification serving as the presenting clinical manifestation of necrotizing CMV retinitis.

High-dose methylprednisolone treatment of laser-induced retinal injury exacerbates acute inflammation and long-term scarring

NASA Astrophysics Data System (ADS)

Schuschereba, Steven T.; Cross, Michael E.; Scales, David K.; Pizarro, Jose M.; Edsall, Peter R.; Stuck, Bruce E.; Marshall, John

1999-06-01

Purpose. To evaluate therapeutics for attenuating retinal laser injury. Methods. New Zealand Red rabbits (n=76) were pretreated (IV) with either a single dose of hydroxyethyl starch conjugated deferoxamine (HES-DFO, n=29) (6.1 ml/kg, 16.4 mg/ml) or methylprednisolone sodium succinate (MP, n=22) (30 mg/kg, followed by taper of 30, 20, 20, and 10 mg/kg/day for a total of 5d). Controls were untreated (n=25). Fifteen min later, animals were irradiated with a multiline cw argon laser (285 mW, 10 msec pulse durations, 16 lesions/eye). Funduscopy, fluorescein angiography, histology, and morphometry were performed at 10 min, 1h, 3h, 24h, 1 mo, and 6 mo after irradiation. Leukocytes were counted at lesion centers for retinal and choroidal compartments at 1, 3, and 24h. Results. At 3h, percent area incrase for the lesions was highest for MP (44%) and lowest for HES-DFO (16%)(p<0.05). In hemorrhagic lesions, MP treatment resulted in the highest increase of retinal neotrophils by 24h (p<0.05), and by 1 and 6 mo extensive chorio-retinal scarring occurred in nonhemorrhagic and hemorrhagic lesions. Also, no benefit was demonstrated on sparing of photoreceptors with MP treatment. Conclusions. Treatment of laser-induced retinal injury with methylprednisolone (MP) exacerbates acute inflammation and long-term chorio-retinal scarring; however, hydroxyethyl starch conjugated deferoxamine therapy ameliorates these aspects of injury. Data suggest caution in the use of MP therapy for laser injuries.

Steroidal and nonsteroidal antiinflammatory medications can improve photoreceptor survival after laser retinal photocoagulation.

PubMed

Brown, Jeremiah; Hacker, Henry; Schuschereba, Steven T; Zwick, Harry; Lund, David J; Stuck, Bruce E

2007-10-01

To determine whether methylprednisolone or indomethacin can enhance photoreceptor survival after laser retinal injury in an animal model. Experimental study. Twenty rhesus monkeys. Twenty rhesus monkeys (Macaca mulatta) received a grid of argon green (514.5 nm, 10 ms) laser lesions in the macula of the right eye and a grid of neodymium:yttrium-aluminum-garnet (Nd:YAG; 1064 nm, 10 ns) lesions in the macula of the left eye, followed by randomization to 2 weeks of treatment in 1 of 4 treatment groups: high-dose methylprednisolone, moderate-dose methylprednisolone, indomethacin, or control. The lesions were assessed at day 1, day 14, 2 months, and 4 months. The authors were masked to the treatment group. This report discusses the histologic results of ocular tissue harvested at 4 months. The number of surviving photoreceptor cell nuclei within each lesion was compared with the number of photoreceptor nuclei in surrounding unaffected retina. The proportion of surviving photoreceptor nuclei was compared between each treatment group. Argon retinal lesions in the high-dose steroid treatment group and the indomethacin treatment group demonstrated improved photoreceptor survival compared with the control group (P = 0.004). Hemorrhagic Nd:YAG lesions demonstrated improved survivability with indomethacin treatment compared with controls (P = 0.003). In nonhemorrhagic Nd:YAG laser retinal lesions, the lesions treated with moderate-dose steroids demonstrated improved photoreceptor survival compared with the control group (P = 0.004). Based on histologic samples of retinal laser lesions 4 months after injury, treatment with indomethacin resulted in improved photoreceptor survival in argon laser lesions and hemorrhagic Nd:YAG laser lesions. Treatment with systemic methylprednisolone demonstrated improved photoreceptor survival in argon retinal lesions and in nonhemorrhagic Nd:YAG lesions.

Diabetic retinopathy and complexity of retinal surgery in a general hospital.

PubMed

Mijangos-Medina, Laura Fanny; Hurtado-Noriega, Blanca Esmeralda; Lima-Gómez, Virgilio

2012-01-01

Usual retinal surgery (vitrectomy or surgery for retinal detachment) may require additional procedures to deal with complex cases, which increase time and resource use and delay access to treatment. We undertook this study to identify the proportion of primary retinal surgeries that required complex procedures and the associated causes. We carried out an observational, descriptive, cross-sectional, retrospective study. Patients with primary retinal surgery were evaluated (January 2007-December 2010). The proportion and 95% confidence intervals (CI) of preoperative diagnosis and cause of the disease requiring retinal surgery as well as the causes for complex retinal surgery were identified. Complex retinal surgery was defined as that requiring lens extraction, intraocular lens implantation, heavy perfluorocarbon liquids, silicone oil tamponade or intravitreal drugs, in addition to the usual surgical retinal procedure. The proportion of complex retinal surgeries was compared among preoperative diagnoses and among causes (χ(2), odds ratio [OR]). We studied 338 eyes. Mean age of subjects was 53.7 years, and there were 49% females. The most common diagnoses were vitreous hemorrhage (27.2%) and rhegmatogenous retinal detachment (24.6%). The most common cause was diabetes (50.6%); 273 eyes required complex surgery (80.8%, 95% CI: 76.6-85). The proportion did not differ among diagnoses but was higher in diabetic retinopathy (89%, p <0.001, OR 3.04, 95% CI: 1.63-5.7). Of the total sample, 80.8% of eyes required complex surgical procedures; diabetic retinopathy increased by 3-fold the probability of requiring these complex procedures. Early treatment of diabetic retinopathy may reduce the proportion of complex retinal surgery by 56%.

Combined use of Doppler OCT and en face OCT functions for discrimination of an aneurysm in the lamina cribrosa from a disc hemorrhage.

PubMed

Holló, Gábor

2015-12-01

In addition to retinal nerve fiber layer thickness measurements, the recently introduced AngioVue optical coherence tomography (OCT) offers corresponding layer-by-layer Doppler OCT and en face OCT functions, for simultaneous evaluation of perfusion and structure of the optic nerve head. We investigated the clinical usefulness of combined use of Doppler and en face Fourier-domain OCT functions of the AngioVue Fourier-domain OCT for discrimination of a disc hemorrhage and a disc hemorrhage-like atypical vessel structure located deep in the lamina cribrosa. We present our findings with AngioVue OCT on a disc hemorrhage and a spatially related retinal nerve fiber layer bundle defect in a glaucomatous eye (case 1). Both alterations were detected on en face OCT images without any Doppler OCT signal. We also report on an aneurysm suggestive for a disc hemorrhage on clinical examination and disc photography in a treated ocular hypertensive eye (case 2). The aneurysm was within the lamina cribrosa tissue at the border of the cup and the neuroretinal rim. This vascular structure produced strong Doppler signals but no structurally detectable signs on the en face OCT images. Combined evaluation of corresponding Doppler OCT and en face OCT images enables ophthalmologists to easily separate true disc hemorrhages from disc hemorrhage-like deep vascular structures. This is of clinical significance in preventing unnecessary intensification of pressure-lowering treatment in glaucoma.

Detection of retinal changes from illumination normalized fundus images using convolutional neural networks

NASA Astrophysics Data System (ADS)

Adal, Kedir M.; van Etten, Peter G.; Martinez, Jose P.; Rouwen, Kenneth; Vermeer, Koenraad A.; van Vliet, Lucas J.

2017-03-01

Automated detection and quantification of spatio-temporal retinal changes is an important step to objectively assess disease progression and treatment effects for dynamic retinal diseases such as diabetic retinopathy (DR). However, detecting retinal changes caused by early DR lesions such as microaneurysms and dot hemorrhages from longitudinal pairs of fundus images is challenging due to intra and inter-image illumination variation between fundus images. This paper explores a method for automated detection of retinal changes from illumination normalized fundus images using a deep convolutional neural network (CNN), and compares its performance with two other CNNs trained separately on color and green channel fundus images. Illumination variation was addressed by correcting for the variability in the luminosity and contrast estimated from a large scale retinal regions. The CNN models were trained and evaluated on image patches extracted from a registered fundus image set collected from 51 diabetic eyes that were screened at two different time-points. The results show that using normalized images yield better performance than color and green channel images, suggesting that illumination normalization greatly facilitates CNNs to quickly and correctly learn distinctive local image features of DR related retinal changes.

A 9 year-old girl with herpes simplex virus type 2 acute retinal necrosis treated with intravitreal foscarnet.

PubMed

King, John; Chung, Mina; DiLoreto, David A

2007-01-01

A 9-year-old girl presented with a 2-week history of redness in the left eye. Examination revealed vitritis, retinal whitening, vasculitis, and optic nerve head edema. Polymerase chain reaction testing of the aqueous fluid revealed herpes simplex virus type 2. The retinitis was controlled with intravenous acyclovir and intravitreal foscarnet. The clinical course was complicated by retinal neovascularization and vitreous hemorrhage, which was treated by pars plana vitrectomy and endolaser. While there are few case reports of herpes simplex virus type 2 retinitis in children, this one is unique for the following reasons: it is the first reported case of herpes simplex virus type 2 retinitis in a child less than 10 years old without a previous history of neonatal infection or central nervous system involvement; no other children have been reported to have been treated with intravitreal foscarnet; and retinal neovascularization complicated the recovery.

A novel platform for minimally invasive delivery of cellular therapy as a thin layer across the subretina for treatment of retinal degeneration

NASA Astrophysics Data System (ADS)

Rotenstreich, Ygal; Tzameret, Adi; Kalish, Sapir E.; Belkin, Michael; Meir, Amilia; Treves, Avraham J.; Nagler, Arnon; Sher, Ifat

2015-03-01

Incurable retinal degenerations affect millions worldwide. Stem cell transplantation rescued visual functions in animal models of retinal degeneration. In those studies cells were transplanted in subretinal "blebs", limited number of cells could be injected and photoreceptor rescue was restricted to areas in proximity to the injection sites. We developed a minimally-invasive surgical platform for drug and cell delivery in a thin layer across the subretina and extravascular spaces of the choroid. The novel system is comprised of a syringe with a blunt-tipped needle and an adjustable separator. Human bone marrow mesenchymal stem cells (hBM-MSCs) were transplanted in eyes of RCS rats and NZW rabbits through a longitudinal triangular scleral incision. No immunosuppressants were used. Retinal function was determined by electroretinogram analysis and retinal structure was determined by histological analysis and OCT. Transplanted cells were identified as a thin layer across the subretina and extravascular spaces of the choroid. In RCS rats, cell transplantation delayed photoreceptor degeneration across the entire retina and significantly enhanced retinal functions. No retinal detachment or choroidal hemorrhages were observed in rabbits following transplantation. This novel platform opens a new avenue for drug and cell delivery, placing the transplanted cells in close proximity to the damaged RPE and retina as a thin layer, across the subretina and thereby slowing down cell death and photoreceptor degeneration, without retinal detachment or choroidal hemorrhage. This new transplantation system may increase the therapeutic effect of other cell-based therapies and therapeutic agents. This study is expected to directly lead to phase I/II clinical trials for autologous hBM-MSCs transplantation in retinal degeneration patients.

Fundus autofluorescence and optical coherence tomography in the management of progressive outer retinal necrosis

PubMed Central

Yeh, Steven; Wong, Wai T.; Weichel, Eric D.; Lew, Julie C.; Chew, Emily Y.; Nussenblatt, Robert B.

2011-01-01

A 41 year-old female patient with acquired immune deficiency syndrome (AIDS) presented with progressive nasal visual field loss in her right eye. Ophthalmic exam revealed widespread areas of retinal opacification with hemorrhage consistent with progressive outer retinal necrosis (PORN), which was confirmed by polymerase chain reaction (PCR) for varicella zoster virus (VZV) DNA. The patient was treated with intravenous and intravitreal foscarnet and ganciclovir with a resultant improvement clinically. Optical coherence tomography (OCT) and fundus autofluorescence (FAF) imaging revealed progressive changes indicative of widespread retinal pigment epithelial (RPE) and outer retinal dysfunction. OCT was useful in documenting progressive changes in macular architecture during therapy including neurosensory elevation, cystoid macular edema, and severe outer retinal necrosis, at initial exam, 1 week, and 1 month follow-up. Fundus autofluorescence revealed areas of stippled, hyperfluorescence within extensive zones of hypofluorescence, which progressed during the follow-up period. These areas appeared to represent lipofuscin or its photoreactive components within larger regions of RPE loss. The combination of OCT and FAF was useful in the characterization of the RPE and retinal anatomy in this patient with PORN. PMID:20337261

Treatment of cytomegalovirus (CMV) retinitis with intravitreous ganciclovir in HIV-infected children.

PubMed

Surachatkumtonekul, Thammanoon; Chokephaibulkit, Kulkanya; Vanprapar, Nirun; Pamonvaechavan, Pittaya

2008-03-01

To evaluate the efficacy, visual outcomes, and complications of intravitreous ganciclovir treatment in cytomegalovirus (CMV) retinitis in HIV-infected children. The medical records of HIV-infected children who were screened for CMV retinitis from February 2002 to February 2005 were reviewed. The children with CD4+ < 15%, or with clinical category C would have complete ophthalmic examination every 3 months. Ganciclovir (4 mg/0.04 ml) was administered intravitreously to the eye with CMV retinitis every 2 weeks under general anaesthesia. After injection, fundi were examined immediately, 1 day, 14 days and every 2 weeks until the lesions were stable. Six (9 eyes) out of 45 children (13%) aged 2-12 years were found to have CMV retinitis. All CMV retinitis lesions were "cheese and ketchup like" (retinal hemorrhage and exudate) lesions and presented in the posterior pole. Bilateral CMV retinitis were found in 3 children. Intravitreous ganciclovir was injected in 4 children (5 eyes). The average number of intravitreous injections for each patient was 5.6 (3-7) times. All of the children received antiretroviral therapy and 3 children also received intravenous ganciclovir CMV retinitis lesions were improved in every eye. The visual acuity (VA) remained stable in 4 eyes, but endophthalmitis developed in one eye a few days after injection. The average duration of follow-up was 13.5 months (3-23 months). CMV retinitis was not uncommon. The authors found that intravitreous ganciclovir was effective but may cause complications. This treatment should be considered in a resource-limited setting.

Iron homeostasis and toxicity in retinal degeneration.

PubMed

He, Xining; Hahn, Paul; Iacovelli, Jared; Wong, Robert; King, Chih; Bhisitkul, Robert; Massaro-Giordano, Mina; Dunaief, Joshua L

2007-11-01

Iron is essential for many metabolic processes but can also cause damage. As a potent generator of hydroxyl radical, the most reactive of the free radicals, iron can cause considerable oxidative stress. Since iron is absorbed through diet but not excreted except through menstruation, total body iron levels buildup with age. Macular iron levels increase with age, in both men and women. This iron has the potential to contribute to retinal degeneration. Here we present an overview of the evidence suggesting that iron may contribute to retinal degenerations. Intraocular iron foreign bodies cause retinal degeneration. Retinal iron buildup resulting from hereditary iron homeostasis disorders aceruloplasminemia, Friedreich's ataxia, and panthothenate kinase-associated neurodegeneration cause retinal degeneration. Mice with targeted mutation of the iron exporter ceruloplasmin have age-dependent retinal iron overload and a resulting retinal degeneration with features of age-related macular degeneration (AMD). Post mortem retinas from patients with AMD have more iron and the iron carrier transferrin than age-matched controls. Over the past 10 years much has been learned about the intricate network of proteins involved in iron handling. Many of these, including transferrin, transferrin receptor, divalent metal transporter-1, ferritin, ferroportin, ceruloplasmin, hephaestin, iron-regulatory protein, and histocompatibility leukocyte antigen class I-like protein involved in iron homeostasis (HFE) have been found in the retina. Some of these proteins have been found in the cornea and lens as well. Levels of the iron carrier transferrin are high in the aqueous and vitreous humors. The functions of these proteins in other tissues, combined with studies on cultured ocular tissues, genetically engineered mice, and eye exams on patients with hereditary iron diseases provide clues regarding their ocular functions. Iron may play a role in a broad range of ocular diseases, including

Iron homeostasis and toxicity in retinal degeneration

PubMed Central

He, Xining; Hahn, Paul; Iacovelli, Jared; Wong, Robert; King, Chih; Bhisitkul, Robert; Massaro-Giordano, Mina; Dunaief, Joshua L.

2007-01-01

Iron is essential for many metabolic processes but can also cause damage. As a potent generator of hydroxyl radical, the most reactive of the free radicals, iron can cause considerable oxidative stress. Since iron is absorbed through diet but not excreted except through menstruation, total body iron levels build up with age. Macular iron levels increase with age, in both men and women. This iron has the potential to contribute to retinal degeneration. Here we present an overview of the evidence suggesting that iron may contribute to retinal degenerations. Intraocular iron foreign bodies cause retinal degeneration. Retinal iron buildup resulting from hereditary iron homeostasis disorders aceruloplasminemia, Friedreich’s Ataxia, and panthothenate kinase associated neurodegeneration cause retinal degeneration. Mice with targeted mutation of the iron exporter ceruloplasmin have age-dependent retinal iron overload and a resulting retinal degeneration with features of age-related macular degeneration (AMD). Post mortem retinas from patients with AMD have more iron and the iron carrier transferrin than age- matched controls. Over the past ten years much has been learned about the intricate network of proteins involved in iron handling. Many of these, including transferrin, transferrin receptor, divalent metal transporter 1, ferritin, ferroportin, ceruloplasmin, hephaestin, iron regulatory protein, and histocompatibility leukocyte antigen class I-like protein involved in iron homeostasis (HFE) have been found in the retina. Some of these proteins have been found in the cornea and lens as well. Levels of the iron carrier transferrin are high in the aqueous and vitreous humors. The functions of these proteins in other tissues, combined with studies on cultured ocular tissues, genetically engineered mice, and eye exams on patients with hereditary iron diseases provide clues regarding their ocular functions. Iron may play a role in a broad range of ocular diseases, including

EN FACE IMAGING OF RETINAL ARTERY MACROANEURYSMS USING SWEPT-SOURCE OPTICAL COHERENCE TOMOGRAPHY.

PubMed

Hanhart, Joel; Strassman, Israel; Rozenman, Yaakov

2017-01-01

To describe the advantages of en face view with swept-source optical coherence tomography in assessing the morphologic features of retinal arterial macroaneurysms, their consequences on adjacent retina, planning laser treatment, and evaluating its effects. Three eyes were treated for retinal arterial macroaneurysms and followed by swept-source optical coherence tomography in 2014-2015. En face images of the retina and choroid were obtained by EnView, a swept-source optical coherence tomography program. Retinal arterial macroaneurysms have a typical optical coherence tomography appearance. En face view allows delineation of the macroaneurysm wall, thrombotic components within the dilation, and lumen measurement. Hemorrhage, lipids, and fluids can be precisely described in terms of amount and extent over the macula and depth. This technique is also practical for planning focal laser treatment and determining its effects. En face swept-source optical coherence tomography is a rapid, noninvasive, high-resolution, promising technology, which allows excellent visualization of retinal arterial macroaneurysms and their consequences on surrounding tissues. It could make angiography with intravenous injection redundant in planning and assessing therapy.

Hemorrhagic

MedlinePlus

... Hemorrhagic diseases are caused by bleeding, or they result in bleeding (hemorrhaging). Related topics include: Primary thrombocythemia (hemorrhagic thrombocythemia) Stroke Yellow fever Bleeding disorders Ebola fever Dengue hemorrhagic ...

Microscope-Integrated Optical Coherence Tomography Angiography in the Operating Room in Young Children With Retinal Vascular Disease.

PubMed

Chen, Xi; Viehland, Christian; Carrasco-Zevallos, Oscar M; Keller, Brenton; Vajzovic, Lejla; Izatt, Joseph A; Toth, Cynthia A

2017-05-01

Intraoperative optical coherence tomography (OCT) has gained traction as an important adjunct for clinical decision making during vitreoretinal surgery, and OCT angiography (OCTA) has provided novel insights in clinical evaluation of retinal diseases. To date, these two technologies have not been applied in combination to evaluate retinal vascular disease in the operating suite. To conduct microscope-integrated, swept-source OCTA (MIOCTA) in children with retinal vascular disease. In this case report analysis, OCT imaging in pediatric patients, MIOCTA images were obtained during examination under anesthesia from a young boy with a history of idiopathic vitreous hemorrhage and a female infant with familial exudative vitreoretinopathy. Side-by-side comparison of research MIOCT angiograms and clinically indicated fluorescein angiograms. In 2 young children with retinal vascular disease, the MIOCTA images showed more detailed vascular patterns than were visible on the fluorescein angiograms although within a more posterior field of view. The MIOCTA system allowed visualization of small pathological retinal vessels in the retinal periphery that were obscured in the fluorescein angiograms by fluorescein staining from underlying, preexisting laser scars. This is the first report to date of the use of MIOCTA in the operating room for young children with retinal vascular disease. Further optimization of this system may allow noninvasive detailed evaluation of retinal vasculature during surgical procedures and in patients who could not cooperate with in-office examinations.

Retinal detachment and retinal holes in retinitis pigmentosa sine pigmento.

PubMed

Csaky, K; Olk, R J; Mahl, C F; Bloom, S M

1991-01-01

Retinal detachment and retinal holes in two family members with retinitis pigmentosa sine pigmento are reported. We believe these are the first such cases reported in the literature. We describe the presenting symptoms and management, including cryotherapy, scleral buckling procedure, and sulfur hexafluoride injection (SF6), resulting in stable visual acuity in one case and retinal reattachment and improved visual acuity in the other case.

Anomalous coagulation factors in non-arteritic anterior ischemic optic neuropathy with central retinal vein occlusion: A case report.

PubMed

Kim, Ji Hong; Kang, Min Ho; Seong, Mincheol; Cho, Heeyoon; Shin, Yong Un

2018-04-01

Non-arteritic anterior ischemic optic neuropathy (NAION) is characterized by sudden, painless visual loss and optic disc edema. NAION occurs mainly in the presence of cardiovascular disease and hypercoagulability, mainly in patients over 50 years of age. We experienced a case of NAION associated with central retinal vein occlusion (CRVO) in a young man with no underlying disease. A 46-year-old man was referred to our clinic following a sudden loss of vision in his right eye. The patient exhibited no underlying disease and reported no ongoing medication. Significant visual loss and visual disturbance of the right eye were observed. The pupil of the right eye was enlarged and an afferent pupillary defect was observed. On fundus examination, retinal hemorrhage was observed in the peripheral retina; macular edema was observed in optical coherence tomography analysis. However, optic disc edema was not evident. No abnormal findings were found in routine blood tests for hypercoagulability. After 3 days of steroid intravenous injection, macular edema disappeared and visual acuity was improved, but optic disc edema began to appear. One week later, optic disc edema was evident and visual acuity was significantly reduced; thus, the patient was diagnosed with NAION. In fluorescein angiography, peripheral retinal ischemia was observed, suggesting that CRVO was complicated. Blood tests, including analysis of coagulation factors, were performed again, showing that coagulation factors IX and XI were increased. Anomalous coagulation factors in non-arteritic anterior ischemic optic neuropathy with central retinal vein occlusion. Systemic steroids were administered. One month later, optic disc edema and retinal hemorrhage gradually diminished and eventually disappeared; however, visual acuity did not recover. In young patients without underlying disease, cases of NAION require careful screening for coagulation disorders. Even if there is no abnormality in the test for routine

Retinal vein occlusion and the risk of stroke development: a 9-year nationwide population-based study.

PubMed

Rim, Tyler Hyungtaek; Kim, Dong Wook; Han, John Seungsoo; Chung, Eun Jee

2015-06-01

To evaluate the risk of stroke development after retinal vein occlusion (RVO). Nationwide, population-based 9-year longitudinal study. National registry data were collected from the Korean National Health Insurance Research Database, comprising 1 025 340 (∼2.2%) random subjects who were selected from 46 605 433 Korean residents in 2002. Patients diagnosed with RVO or stroke in 2002 were excluded. The RVO group was composed of patients with an initial diagnosis of central or branch RVO between January 2003 and December 2005 (n = 344 in 2003, 375 in 2004, and 312 in 2005). The comparison group was composed of randomly selected patients (5 per patient with RVO; n = 1696 in 2003, 1854 in 2004, and 1524 in 2005) who were matched to the RVO group according to age, sex, residential area, household income, and year of RVO diagnosis. Each sampled patient was tracked until 2010. Cox proportional hazard regressions were used to calculate the overall survival rate for stroke development after adjusting for potential confounders, including hypertension, diabetes mellitus, and chronic kidney disease. Retinal vein occlusion and ischemic or hemorrhagic stroke based on the International Classification of Disease codes. Stroke developed in 16.8% of the RVO group and in 10.7% of the comparison group. Retinal vein occlusion was associated with an increased risk of stroke development (hazard ratio [HR], 1.48; 95% confidence interval [CI], 1.24-1.76). Hypertension, diabetes mellitus, and chronic kidney disease also increased the risk of stroke development. In addition, RVO increased the risk of both ischemic stroke (HR, 1.51; 95% CI, 1.24-1.84) and hemorrhagic stroke (HR, 1.30; 95% CI, 0.83-2.05), although this result was not significant for hemorrhagic stroke. In terms of age, the effect size of the HR was largest among younger adults, aged <50 years (HR, 2.69), compared with middle-aged adults, aged 50 to 69 years (HR, 1.33), and older adults, aged ≥70 years (HR, 1.46). Retinal

Molecular diagnosis and ocular imaging of West Nile virus retinitis and neuroretinitis.

PubMed

Sivakumar, Rathinam R; Prajna, Lalitha; Arya, Lalan Kumar; Muraly, Praveen; Shukla, Jyoti; Saxena, Divyasha; Parida, Manmohan

2013-09-01

To describe the ocular features of West Nile virus (WNV) infection proven by serology and molecular diagnostic techniques. Prospective case series. Fifty-two patients who presented to the uveitis clinic with ocular inflammatory signs and history of fever preceding ocular symptoms between January 2010 and January 2012 were enrolled for laboratory diagnosis. Serum samples were collected from 30 healthy controls from the same geographic area. Patients were tested for all endemic infectious diseases that can cause ocular inflammation by serology or molecular diagnostics. When patients had positive antibodies for WNV, serum/plasma samples were tested by real-time reverse transcription (RT) polymerase chain reaction (PCR) and RT loop-mediated isothermal gene amplification assays. The PCR product was subjected to nucleotide sequencing. Fundus fluorescence angiography (FFA), optical coherence tomography (OCT), and indocyanine green angiography were performed. Visual prognosis was analyzed. Clinical signs (retinitis, neuroretinitis, and choroiditis) and ocular complications (decrease in vision). A total of 37 of 52 patients (71%) showed positive results for at least 2 laboratory tests for WNV. Fundus examination revealed discrete, superficial, white retinitis; arteritis; phlebitis; and retinal hemorrhages with or without macular star. The FFA revealed areas of retinal inflammation with indistinct borders, vascular and optic disc leakage, vessel wall staining, or capillary nonperfusion. Indocyanine green angiography confirmed choroidal inflammation in 1 of the patients who was diabetic. The OCT scan of the macula revealed inner retinal layer edema in active inflammation and retinal atrophy in late stage. At the final visit, 43% of patients had visual acuity better than 6/12. In addition to previously reported clinical signs, retinitis, neuroretinitis, and retinal vasculitis were seen in this population. Atrophy of the inner retinal layer was seen on OCT after resolution of

Retinal response of Macaca mulatta to picosecond laser pulses of varying energy and spot size.

PubMed

Roach, William P; Cain, Clarence P; Narayan, Drew G; Noojin, Gary D; Boppart, Stephen A; Birngruber, Reginald; Fujimoto, James G; Toth, Cynthia A

2004-01-01

We investigate the relationship between the laser beam at the retina (spot size) and the extent of retinal injury from single ultrashort laser pulses. From previous studies it is believed that the retinal effect of single 3-ps laser pulses should vary in extent and location, depending on the occurrence of laser-induced breakdown (LIB) at the site of laser delivery. Single 3-ps pulses of 580-nm laser energy are delivered over a range of spot sizes to the retina of Macaca mulatta. The retinal response is captured sequentially with optical coherence tomography (OCT). The in vivo OCT images and the extent of pathology on final microscopic sections of the laser site are compared. With delivery of a laser pulse with peak irradiance greater than that required for LIB, OCT and light micrographs demonstrate inner retinal injury with many intraretinal and/or vitreous hemorrhages. In contrast, broad outer retinal injury with minimal to no choriocapillaris effect is seen after delivery of laser pulses to a larger retinal area (60 to 300 microm diam) when peak irradiance is less than that required for LIB. The broader lesions extend into the inner retina when higher energy delivery produces intraretinal injury. Microscopic examination of stained fixed tissues provide better resolution of retinal morphology than OCT. OCT provides less resolution but could be guided over an in vivo, visible retinal lesion for repeated sampling over time during the evolution of the lesion formation. For 3-ps visible wavelength laser pulses, varying the spot size and laser energy directly affects the extent of retinal injury. This again is believed to be partly due to the onset of LIB, as seen in previous studies. Spot-size dependence should be considered when comparing studies of retinal effects or when pursuing a specific retinal effect from ultrashort laser pulses. Copyright 2004 Society of Photo-Optical Instrumentation Engineers.

Retinal oximetry in patients with ischaemic retinal diseases.

PubMed

Rilvén, Sandra; Torp, Thomas Lee; Grauslund, Jakob

2017-03-01

The retinal oximeter is a new tool for non-invasive measurement of retinal oxygen saturation in humans. Several studies have investigated the associations between retinal oxygen saturation and retinal diseases. In the present systematic review, we examine whether there are associations between retinal oxygen saturation and retinal ischaemic diseases. We used PubMed and Embase to search for retinal oxygen saturation and retinal ischaemic diseases. Three separate searches identified a total of 79 publications. After two levels of manual screening, 10 studies were included: six about diabetic retinopathy (DR) and four about retinal vein occlusion. No studies about retinal artery occlusion were included. In diabetes, all studies found that increases in retinal venous oxygen saturation (rvSatO 2 ) were associated with present as well as increasing levels of DR. Four of six studies also found increased retinal arterial oxygen saturation (raSatO 2 ) in patients with DR. In patients with central retinal vein occlusion (CRVO), all studies found that rvSatO 2 was reduced, but raSatO 2 remained unchanged. Branch retinal vein occlusion was not associated with changes in retinal oxygen saturation, but this was based on a single study. In conclusion, DR is associated with increased rvSatO 2 and might also be related to increased raSatO 2 . Central retinal vein occlusion (CRVO) is correlated with increased rvSatO 2 but unrelated to raSatO 2 . Prospective studies are needed to expand these findings. These would tell whether retinal oximetry could be a potential tool for screening or a biomarker of treatment outcome in patients with ischaemic retinal diseases. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Comparison of a digital retinal imaging system and seven-field stereo color fundus photography to detect diabetic retinopathy in the primary care environment.

PubMed

Schiffman, Rhett M; Jacobsen, Gordon; Nussbaum, Julian J; Desai, Uday R; Carey, J David; Glasser, David; Zimmer-Galler, Ingrid E; Zeimer, Ran; Goldberg, Morton F

2005-01-01

Because patients with diabetes mellitus may visit their primary care physician regularly but not their ophthalmologist, a retinal risk assessment in the primary care setting could improve the screening rate for diabetic retinopathy. An imaging system for use in the primary care setting to identify diabetic retinopathy requiring referral to an ophthalmologist was evaluated. In a masked prospective study, images were obtained from 11 patients with diabetes mellitus using both the digital retinal imaging system and seven-field stereo color fundus photography. The ability to obtain gradable images and to identify diabetic retinal lesions was compared. Of all images, 85% of digital retinal imaging system images and 88% of seven-field images were gradable. Agreement based on "no retinopathy" versus "any retinopathy" was excellent (Kappa = 0.96). Agreement based on "microaneurysms or less retinopathy" versus "retinal hemorrhages or worse retinopathy" was very good (Kappa = 0.83). The agreement between the digital retinal imaging system and seven-field photography indicates that the digital retinal imaging system may be useful to screen for diabetic retinopathy.

The Effects of the Contact Activation System on Hemorrhage

PubMed Central

Simão, Fabrício; Feener, Edward P.

2017-01-01

The contact activation system (CAS) exerts effects on coagulation via multiple mechanisms, which modulate both the intrinsic and extrinsic coagulation cascades as well as fibrinolysis and platelet activation. While the effects of the CAS on blood coagulation measured as activated partial thromboplastin time shortening are well documented, genetic mutations that result in deficiencies in the expression of either plasma prekallikrein (PPK) or factor XII (FXII) are not associated with spontaneous bleeding or increased bleeding risk during surgery. Deficiencies in these proteins are often undiagnosed for decades and detected later in life during routine coagulation assays without an apparent clinical phenotype. Increased interest in the CAS as a potentially safe target for antithrombotic therapies has emerged, in large part, from studies on animal models with provoked thrombosis, which have shown that deficiencies in PPK or FXII can reduce thrombus formation without increasing bleeding. Gene targeting and pharmacological studies in healthy animals have confirmed that PPK and FXII blockade does not cause coagulopathies. These findings support the conclusion that CAS is not required for hemostasis. However, while deficiencies in FXII and PPK do not significantly affect bleeding associated with peripheral wounds, recent reports have demonstrated that these proteins can promote hemorrhage in the retina and brain. Intravitreal injection of plasma kallikrein (PKal) induces retinal hemorrhage and intracerebral injection of PKal increases intracranial bleeding. PPK deficiency and PKal inhibition ameliorates hematoma formation following cerebrovascular injury in diabetic animals. Moreover, both PPK and FXII deficiency are protective against intracerebral hemorrhage caused by tissue plasminogen activator-mediated thrombolytic therapy in mice with thrombotic middle cerebral artery occlusion. Thus, while the CAS is not required for hemostasis, its inhibition may provide an

Predicting the Significance of Injuries Potentially Caused by Non-Lethal Weapons: Tympanic Membrane Rupture (TMR), Permanent Threshold Shift (PTS), and Photothermal Retinal Lesions

DTIC Science & Technology

2016-06-21

during cooking . Retinal Lesions: medical care 29 of 37 • Suprathreshold lesions can lead to complications like hemorrhage, macular holes and...Effects Review Board (HERB). Members of the multi-service HERB include health care professionals and safety officers. The purpose of IDA’s analyses

Retinitis Pigmentosa

MedlinePlus

... Action You are here Home › Retinal Diseases Listen Retinitis Pigmentosa What is retinitis pigmentosa? What are the symptoms? ... is available? What treatment is available? What is retinitis pigmentosa? Retinitis pigmentosa, also known as RP, refers to ...

Outer Retinal Tubulation in Degenerative Retinal Disorders

PubMed Central

Goldberg, Naomi R.; Greenberg, Jonathan P.; Laud, Ketan; Tsang, Stephen; Freund, K. Bailey

2013-01-01

Objective To demonstrate outer retinal tubulation (ORT) in various degenerative retinal disorders. Methods This was a retrospective review of the multimodal imaging of 29 eyes of 15 patients with various retinal dystrophies and inflammatory maculopathies manifesting ORT. The morphologic features of ORT and its evolution over time were analyzed using spectral-domain optical coherence tomography (SD-OCT) data. Results Outer retinal tubulation was identified as round or ovoid structures with hyper-reflective borders in pattern dystrophy (6 eyes), acute zonal occult outer retinopathy (5 eyes), retinitis pigmentosa (4 eyes), Stargardt disease (4 eyes), gyrate atrophy (2 eyes), choroideremia (2 eyes), and various other degenerative conditions. These structures appeared to develop from the invagination of photoreceptors at the junction of intact and atrophic outer retina. During follow-up, the number and distribution of ORT largely remained stable. As zones of atrophy enlarged, the frequency of ORT appeared to increase. The ORT structures were found in fewer than 10% of patients with retinitis pigmentosa, Stargardt, or pattern dystrophy. Conclusion Outer retinal tubulation is found in various degenerative retinal disorders that share in common damage to the outer retina and/or retinal pigment epithelium. The presence of ORT may be in an indicator of underlying disease stage and severity. PMID:23676993

Ophthalmoscopic findings in adult patients with severe falciparum malaria.

PubMed

Mehta, Salil A; Ansari, Abdul Samad; Jiandani, Prakash

2008-01-01

To report the systemic and ocular findings of four Indian adult patients with severe Plasmodium falciparum infection. Case reports. The commonest findings seen were posterior pole hemorrhages that were seen in all patients. These included superficial and subretinal hemorrhages. Some of the eyes with subretinal hemorrhages were associated with a premacular hemorrhage. The findings of retinal whitening and vascular changes were seen in one patient. A spectrum of ocular lesions was noted, including pre-retinal, subretinal hemorrhages, retinal whitening, and retinal vascular anomalies.

Case of cytomegalovirus retinitis aggravated by sub-Tenon injection of triamcinolone acetonide with subsequent metastatic liver cancer

PubMed Central

Yamamoto, Yumiko; Kato, Yoshitake; Tabuchi, Hitoshi; Fukushima, Atsuki

2013-01-01

We report a case of cytomegalovirus (CMV) retinitis in an immunocompetent patient who was resistant to antiviral treatment, and in whom fatal metastatic liver cancer was later detected. A 74-year-old Japanese man visited our ophthalmology clinic in May 2011. He had a history of well controlled type 2 diabetes and colon cancer, and underwent successful surgical treatment in 2008. In April 2011, he was diagnosed with uveitis affecting his left eye and received posterior sub-Tenon injection of triamcinolone acetonide. He was referred to us because of aggravation of the retinal lesion. Funduscopic examination of the left eye revealed arcuate, whitish, necrotizing retinitis with hemorrhage along the temporal arcade of the retina. Polymerase chain reaction of the aqueous fluid was positive for CMV DNA. Because of diagnosis of CMV retinitis in his left eye, he was referred to an internist and investigated for systemic CMV infection or any serious disease which could cause immunocompromise, but neither was detected. Despite an intensive course of intravitreous ganciclovir and oral valganciclovir, the retinitis did not resolve. In June 2012, 14 months after the initial ocular symptoms, metastatic liver cancer was found and the patient passed away. When CMV retinitis is resistant to antiviral treatment or recurs in an immunocompetent patient, it is important that ophthalmologists undertake systemic investigation for occult malignancy. PMID:23467884

Progressive outer retinal necrosis-like retinitis in immunocompetent hosts.

PubMed

Chawla, Rohan; Tripathy, Koushik; Gogia, Varun; Venkatesh, Pradeep

2016-08-10

We describe two young immunocompetent women presenting with bilateral retinitis with outer retinal necrosis involving posterior pole with centrifugal spread and multifocal lesions simulating progressive outer retinal necrosis (PORN) like retinitis. Serology was negative for HIV and CD4 counts were normal; however, both women were on oral steroids at presentation for suspected autoimmune chorioretinitis. The retinitis in both eyes responded well to oral valaciclovir therapy. However, the eye with the more fulminant involvement developed retinal detachment with a loss of vision. Retinal atrophy was seen in the less involved eye with preservation of vision. Through these cases, we aim to describe a unique evolution of PORN-like retinitis in immunocompetent women, which was probably aggravated by a short-term immunosuppression secondary to oral steroids. 2016 BMJ Publishing Group Ltd.

Retinal Oximetry Discovers Novel Biomarkers in Retinal and Brain Diseases.

PubMed

Stefánsson, Einar; Olafsdottir, Olof Birna; Einarsdottir, Anna Bryndis; Eliasdottir, Thorunn Scheving; Eysteinsson, Thor; Vehmeijer, Wouter; Vandewalle, Evelien; Bek, Toke; Hardarson, Sveinn Hakon

2017-05-01

Biomarkers for several eye and brain diseases are reviewed, where retinal oximetry may help confirm diagnosis or measure severity of disease. These include diabetic retinopathy, central retinal vein occlusion (CRVO), retinitis pigmentosa, glaucoma, and Alzheimer's disease. Retinal oximetry is based on spectrophotometric fundus imaging and measures oxygen saturation in retinal arterioles and venules in a noninvasive, quick, safe manner. Retinal oximetry detects changes in oxygen metabolism, including those that result from ischemia or atrophy. In diabetic retinopathy, venous oxygen saturation increases and arteriovenous difference decreases. Both correlate with diabetic retinopathy severity as conventionally classified on fundus photographs. In CRVO, vein occlusion causes hypoxia, which is measured directly by retinal oximetry to confirm the diagnosis and measure severity. In both diseases, the change in oxygen levels is a consequence of disturbed blood flow with resulting tissue hypoxia and vascular endothelial growth factor (VEGF) production. In atrophic diseases, such as retinitis pigmentosa and glaucoma, retinal oxygen consumption is reduced and this is detected by retinal oximetry. Retinal oximetry correlates with visual field damage and retinal atrophy. It is an objective metabolic measure of the degree of retinal atrophy. Finally, the retina is part of the central nervous system tissue and reflects central nervous system diseases. In Alzheimer's disease, a change in retinal oxygen metabolism has been discovered. Retinal oximetry is a novel, noninvasive technology that opens the field of metabolic imaging of the retina. Biomarkers in metabolic, ischemic, and atrophic diseases of the retina and central nervous system have been discovered.

Retinal Vasculitis

PubMed Central

Rosenbaum, James T.; Sibley, Cailin H.; Lin, Phoebe

2016-01-01

Purpose of review Ophthalmologists and rheumatologists frequently miscommunicate in consulting on patients with retinal vasculitis. This report seeks to establish a common understanding of the term, retinal vasculitis, and to review recent papers on this diagnosis. Recent findings 1) The genetic basis of some rare forms of retinal vascular disease have recently been described. Identified genes include CAPN5, TREX1, and TNFAIP3; 2) Behçet’s disease is a systemic illness that is very commonly associated with occlusive retinal vasculitis; 3) retinal imaging including fluorescein angiography and other newer imaging modalities has proven crucial to the identification and characterization of retinal vasculitis and its complications; 4) although monoclonal antibodies to IL-17A or IL-1 beta failed in trials for Behçet’s disease, antibodies to TNF alpha, either infliximab or adalimumab, have demonstrated consistent benefit in managing this disease. Interferon treatment and B cell depletion therapy via rituximab may be beneficial in certain types of retinal vasculitis. Summary Retinal vasculitis is an important entity for rheumatologists to understand. Retinal vasculitis associated with Behçet’s disease responds to monoclonal antibodies that neutralize TNF, but the many other forms of non-infectious retinal vasculitis may require alternate therapeutic management. PMID:26945335

Central retinal artery occlusion - rethinking retinal survival time.

PubMed

Tobalem, Stephan; Schutz, James S; Chronopoulos, Argyrios

2018-04-18

The critical time from onset of complete occlusion of the central retinal artery (CRA) to functionally significant inner retinal infarction represents a window of opportunity for treatment and also has medical-legal implications, particularly when central retinal artery occlusion (CRAO) complicates therapeutic interventions. Here, we review the evidence for time to infarction from complete CRAO and discuss the implications of our findings. A Medline search was performed using each of the terms "central retinal artery occlusion", "retinal infarction", "retinal ischemia", and "cherry red spot" from 1970 to the present including articles in French and German. All retrieved references as well as their reference lists were screened for relevance. An Internet search using these terms was also performed to look for additional references. We find that the experimental evidence showing that inner retinal infarction occurs after 90-240 min of total CRAO, which is the interval generally accepted in the medical literature and practice guidelines, is flawed in important ways. Moreover, the retinal ganglion cells, supplied by the CRA, are part of the central nervous system which undergoes infarction after non-perfusion of 12-15 min or less. Retinal infarction is most likely to occur after only 12-15 min of complete CRAO. This helps to explain why therapeutic maneuvers for CRAO are often ineffective. Nevertheless, many CRAOs are incomplete and may benefit from therapy after longer intervals. To try to avoid retinal infarcton from inadvertent ocular compression by a headrest during prone anesthesia, the eyes should be checked at intervals of less than 15'.

Acute-onset floaters and flashes: is this patient at risk for retinal detachment?

PubMed

Hollands, Hussein; Johnson, Davin; Brox, Anya C; Almeida, David; Simel, David L; Sharma, Sanjay

2009-11-25

Acute onset of monocular floaters and/or flashes represents a common presentation to primary care physicians, and the most likely diagnosis is posterior vitreous detachment (PVD). A significant proportion of patients with acute PVD develop an associated retinal tear that can lead to retinal detachment and permanent vision loss if left untreated. To quantify the association between relevant clinical variables and risk of retinal tear in patients presenting with acute-onset floaters and/or flashes and PVD. Structured MEDLINE (January 1950-September 2009) and EMBASE (January 1980-September 2009) searches and a hand search of references and citations of retrieved articles yielded 17 relevant studies. Studies of high-level methods that related elements of the history or physical examination in patients presenting with floaters and/or flashes and PVD to the likelihood of retinal tear. For patients with acute onset of floaters and/or flashes who are self-referred or referred to an ophthalmologist, the prevalence of retinal tear is 14% (95% confidence interval [CI], 12%-16%). Subjective visual reduction is the most important symptom associated with retinal tear (likelihood ratio [LR], 5.0; 95% CI, 3.1-8.1). Vitreous hemorrhage on slitlamp biomicroscopy is the best-studied finding with the narrowest positive LR for retinal tear (summary LR, 10; 95% CI, 5.1-20). Absence of vitreous pigment during this examination is the best-studied finding with the narrowest negative LR (summary LR, 0.23; 95% CI, 0.12-0.43). Patients initially diagnosed as having uncomplicated PVD have a 3.4% chance of a retinal tear within 6 weeks. The risk increases with new onset of at least 10 floaters (summary LR, 8.1-36) or subjective visual reduction (summary LR, 2.3-17) during this period. Primary care physicians should evaluate patients with acute-onset floaters and/or flashes due to suspected PVD, or patients with known PVD and a change in symptoms, for high-risk features of retinal tear and

Focal retinal phlebitis.

PubMed

Hoang, Quan V; Freund, K Bailey; Klancnik, James M; Sorenson, John A; Cunningham, Emmett T; Yannuzzi, Lawrence A

2012-01-01

To report three cases of solitary, focal retinal phlebitis. An observational case series. Three eyes in three patients were noted to have unilateral decreased vision, macular edema, and a focal retinal phlebitis, which was not at an arteriovenous crossing. All three patients developed a branch retinal vein occlusion at the site of inflammation. These patients had no other evidence of intraocular inflammation, including vitritis, retinitis, retinal vasculitis, or choroiditis, nor was there any systemic disorder associated with inflammation, infection, or coagulation identified. Focal retinal phlebitis appears to be an uncommon and unique entity that produces macular edema and ultimately branch retinal vein occlusion. In our patients, the focal phlebitis and venous occlusion did not occur at an arteriovenous crossing, which is the typical site for branch retinal venous occlusive disease. This suggests that our cases represent a distinct clinical entity, which starts with a focal abnormality in the wall of a retinal venule, resulting in surrounding exudation and, ultimately, ends with branch retinal vein occlusion.

The Role of Prothrombotic Factors in the Ocular Manifestations of Abusive and Non-Abusive Head Trauma: A Feasibility Study

ERIC Educational Resources Information Center

Yu, Anna; Stephens, Derek; Feldman, Brian M.; Parkin, Patricia C.; Kahr, Walter H. A.; Brandao, Leonardo R.; Shouldice, Michelle; Levin, Alex V.

2012-01-01

Objectives: Retinal hemorrhage is a cardinal manifestation of abusive head injury. Thrombophilia is relatively common in the general population and in adults can be associated with retinal hemorrhage. The specificity of retinal hemorrhage for abusive head trauma in the presence of prothrombotic factors, in particular following non-abusive head…

Retinal flavoprotein autofluorescence as a measure of retinal health.

PubMed

Elner, Susan G; Elner, Victor M; Field, Matthew G; Park, Seung; Heckenlively, John R; Petty, Howard R

2008-01-01

To establish that increased autofluorescence of mitochondrial flavoproteins, an indicator of mitochondrial oxidative stress, correlates with retinal cell dysfunction. Retinal flavoprotein autofluorescence (FA) was imaged in humans with a fundus camera modified with 467DF8-nm excitation and 535-nm emission filters and a back-illuminated, electron-multiplying, charge-coupled device camera interfaced with a computer equipped with customized image capture software. Multiple digital images, centered on the fovea, were obtained from each eye. Histograms of pixel intensities in grayscale units were analyzed for average intensity and average curve width. Adults with diabetes mellitus, age-related macular degeneration (ARMD), central serous retinopathy, and retinal dystrophies, as well as healthy control volunteers, were imaged. Monolayers of cultured human retinal pigment epithelial (HRPE) cells, HRPE cells exposed to sublethal doses of H2O2, and HRPE cells exposed to H2O2 in the presence of antioxidants were imaged for FA using fluorescent photomicroscopy. Control patients demonstrated low levels of retinal FA, which increased progressively with age. Diabetics without visible retinopathy demonstrated increased FA levels compared to control volunteers (P < .001). Diabetics with retinopathy demonstrated significantly higher FA values than those without retinopathy (P < .04). Patients with ARMD, central serous retinopathy, or retinal dystrophies also demonstrated significantly increased FA. Compared to control RPE cells, cells oxidatively stressed with H2O2 had significantly elevated FA (P < .05), which was prevented by antioxidants (P < .05). Retinal FA is significantly increased with age and diseases known to be mediated by oxidative stress. Retinal FA imaging may provide a novel, noninvasive method of assessing retinal health and retinal dysfunction prior to retinal cell death.

Hypoxia-induced retinal neovascularization in zebrafish embryos: a potential model of retinopathy of prematurity.

PubMed

Wu, Yu-Ching; Chang, Chao-Yuan; Kao, Alex; Hsi, Brian; Lee, Shwu-Huey; Chen, Yau-Hung; Wang, I-Jong

2015-01-01

Retinopathy of prematurity, formerly known as a retrolental fibroplasia, is a leading cause of infantile blindness worldwide. Retinopathy of prematurity is caused by the failure of central retinal vessels to reach the retinal periphery, creating a nonperfused peripheral retina, resulting in retinal hypoxia, neovascularization, vitreous hemorrhage, vitreoretinal fibrosis, and loss of vision. We established a potential retinopathy of prematurity model by using a green fluorescent vascular endothelium zebrafish transgenic line treated with cobalt chloride (a hypoxia-inducing agent), followed by GS4012 (a vascular endothelial growth factor inducer) at 24 hours postfertilization, and observed that the number of vascular branches and sprouts significantly increased in the central retinal vascular trunks 2-4 days after treatment. We created an angiography method by using tetramethylrhodamine dextran, which exhibited severe vascular leakage through the vessel wall into the surrounding retinal tissues. The quantification of mRNA extracted from the heads of the larvae by using real-time quantitative polymerase chain reaction revealed a twofold increase in vegfaa and vegfr2 expression compared with the control group, indicating increased vascular endothelial growth factor signaling in the hypoxic condition. In addition, we demonstrated that the hypoxic insult could be effectively rescued by several antivascular endothelial growth factor agents such as SU5416, bevacizumab, and ranibizumab. In conclusion, we provide a simple, highly reproducible, and clinically relevant retinopathy of prematurity model based on zebrafish embryos; this model may serve as a useful platform for clarifying the mechanisms of human retinopathy of prematurity and its progression.

Hypoxia-Induced Retinal Neovascularization in Zebrafish Embryos: A Potential Model of Retinopathy of Prematurity

PubMed Central

Kao, Alex; Hsi, Brian; Lee, Shwu-Huey; Chen, Yau-Hung; Wang, I-Jong

2015-01-01

Retinopathy of prematurity, formerly known as a retrolental fibroplasia, is a leading cause of infantile blindness worldwide. Retinopathy of prematurity is caused by the failure of central retinal vessels to reach the retinal periphery, creating a nonperfused peripheral retina, resulting in retinal hypoxia, neovascularization, vitreous hemorrhage, vitreoretinal fibrosis, and loss of vision. We established a potential retinopathy of prematurity model by using a green fluorescent vascular endothelium zebrafish transgenic line treated with cobalt chloride (a hypoxia-inducing agent), followed by GS4012 (a vascular endothelial growth factor inducer) at 24 hours postfertilization, and observed that the number of vascular branches and sprouts significantly increased in the central retinal vascular trunks 2–4 days after treatment. We created an angiography method by using tetramethylrhodamine dextran, which exhibited severe vascular leakage through the vessel wall into the surrounding retinal tissues. The quantification of mRNA extracted from the heads of the larvae by using real-time quantitative polymerase chain reaction revealed a twofold increase in vegfaa and vegfr2 expression compared with the control group, indicating increased vascular endothelial growth factor signaling in the hypoxic condition. In addition, we demonstrated that the hypoxic insult could be effectively rescued by several antivascular endothelial growth factor agents such as SU5416, bevacizumab, and ranibizumab. In conclusion, we provide a simple, highly reproducible, and clinically relevant retinopathy of prematurity model based on zebrafish embryos; this model may serve as a useful platform for clarifying the mechanisms of human retinopathy of prematurity and its progression. PMID:25978439

Protection of retinal function by sulforaphane following retinal ischemic injury.

PubMed

Ambrecht, Lindsay A; Perlman, Jay I; McDonnell, James F; Zhai, Yougang; Qiao, Liang; Bu, Ping

2015-09-01

Sulforaphane, a precursor of glucosinolate in cruciferous vegetables such as broccoli and cauliflower, has been shown to protect brain ischemic injury. In this study, we examined the effect of systemic administration of sulforaphane on retinal ischemic reperfusion injury. Intraocular pressure was elevated in two groups of C57BL/6 mice (n = 8 per group) for 45 min to induce retinal ischemic reperfusion injury. Following retinal ischemic reperfusion injury, vehicle (1% DMSO saline) or sulforaphane (25 mg/kg/day) was administered intraperitoneally daily for 5 days. Scotopic electroretinography (ERG) was used to quantify retinal function prior to and one-week after retinal ischemic insult. Retinal morphology was examined one week after ischemic insult. Following ischemic reperfusion injury, ERG a- and b-wave amplitudes were significantly reduced in the control mice. Sulforaphane treatment significantly attenuated ischemic-induced loss of retinal function as compared to vehicle treated mice. In vehicle treated mice, ischemic reperfusion injury produced marked thinning of the inner retinal layers, but the thinning of the inner retinal layers appeared significantly less with sulforaphane treatment. Thus, sulforaphane may be beneficial in the treatment of retinal disorders with ischemic reperfusion injury. Copyright © 2015 Elsevier Ltd. All rights reserved.

Retinal Remodeling in Human Retinitis Pigmentosa

PubMed Central

Jones, B.W.; Pfeiffer, R.L.; Ferrell, W. D.; Watt, C.B.; Marmor, M.; Marc, R.E.

2016-01-01

Retinitis Pigmentosa (RP) in the human is a progressive, currently irreversible neural degenerative disease usually caused by gene defects that disrupt the function or architecture of the photoreceptors. While RP can initially be a disease of photoreceptors, there is increasing evidence that the inner retina becomes progressively disorganized as the outer retina degenerates. These alterations have been extensively described in animal models, but remodeling in humans has not been as well characterized. This study, using computational molecular phenotyping (CMP) seeks to advance our understanding of the retinal remodeling process in humans. We describe cone mediated preservation of overall topology, retinal reprogramming in the earliest stages of the disease in retinal bipolar cells, and alterations in both small molecule and protein signatures of neurons and glia. Furthermore, while Müller glia appear to be some of the last cells left in the degenerate retina, they are also one of the first cell classes in the neural retina to respond to stress which may reveal mechanisms related to remodeling and cell death in other retinal cell classes. Also fundamentally important is the finding that retinal network topologies are altered. Our results suggest interventions that presume substantial preservation of the neural retina will likely fail in late stages of the disease. Even early intervention offers no guarantee that the interventions will be immune to progressive remodeling. Fundamental work in the biology and mechanisms of disease progression are needed to support vision rescue strategies. PMID:27020758

Retinal detachment

PubMed Central

2009-01-01

Introduction Rhegmatogenous retinal detachment (RRD) is the most common form of retinal detachment, where a retinal "break" allows the ingress of fluid from the vitreous cavity to the subretinal space, resulting in retinal separation. It occurs in about 1 in 10,000 people a year. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of interventions to prevent progression from retinal breaks or lattice degeneration to retinal detachment? What are the effects of different surgical interventions in people with rhegmatogenous retinal detachment? What are the effects of interventions to treat proliferative vitreoretinopathy occurring as a complication of retinal detachment or previous treatment for retinal detachment? We searched: Medline, Embase, The Cochrane Library, and other important databases up to March 2009 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 20 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review, we present information relating to the effectiveness and safety of the following interventions: corticosteroids; cryotherapy; daunorubicin; fluorouracil plus low-molecular-weight heparin; laser photocoagulation; pneumatic retinopexy; scleral buckling; short-acting or long-acting gas tamponade; silicone oil tamponade; and vitrectomy. PMID:19450333

Retinal detachment

PubMed Central

2010-01-01

Introduction Rhegmatogenous retinal detachment (RRD) is the most common form of retinal detachment, where a retinal "break" allows the ingress of fluid from the vitreous cavity to the subretinal space, resulting in retinal separation. It occurs in about 1 in 10,000 people a year. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of interventions to prevent progression from retinal breaks or lattice degeneration to retinal detachment? What are the effects of different surgical interventions in people with rhegmatogenous retinal detachment? What are the effects of interventions to treat proliferative vitreoretinopathy occurring as a complication of retinal detachment or previous treatment for retinal detachment? We searched: Medline, Embase, The Cochrane Library, and other important databases up to June 2010 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 21 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review, we present information relating to the effectiveness and safety of the following interventions: corticosteroids, cryotherapy, daunorubicin, fluorouracil plus low molecular weight heparin, laser photocoagulation, pneumatic retinopexy, scleral buckling, short-acting or long-acting gas tamponade, silicone oil tamponade, and vitrectomy. PMID:21406128

Multi-level deep supervised networks for retinal vessel segmentation.

PubMed

Mo, Juan; Zhang, Lei

2017-12-01

Changes in the appearance of retinal blood vessels are an important indicator for various ophthalmologic and cardiovascular diseases, including diabetes, hypertension, arteriosclerosis, and choroidal neovascularization. Vessel segmentation from retinal images is very challenging because of low blood vessel contrast, intricate vessel topology, and the presence of pathologies such as microaneurysms and hemorrhages. To overcome these challenges, we propose a neural network-based method for vessel segmentation. A deep supervised fully convolutional network is developed by leveraging multi-level hierarchical features of the deep networks. To improve the discriminative capability of features in lower layers of the deep network and guide the gradient back propagation to overcome gradient vanishing, deep supervision with auxiliary classifiers is incorporated in some intermediate layers of the network. Moreover, the transferred knowledge learned from other domains is used to alleviate the issue of insufficient medical training data. The proposed approach does not rely on hand-crafted features and needs no problem-specific preprocessing or postprocessing, which reduces the impact of subjective factors. We evaluate the proposed method on three publicly available databases, the DRIVE, STARE, and CHASE_DB1 databases. Extensive experiments demonstrate that our approach achieves better or comparable performance to state-of-the-art methods with a much faster processing speed, making it suitable for real-world clinical applications. The results of cross-training experiments demonstrate its robustness with respect to the training set. The proposed approach segments retinal vessels accurately with a much faster processing speed and can be easily applied to other biomedical segmentation tasks.

Combined Central Retinal Vein and Branch Retinal Artery Occlusion Post Intense Physical Activity.

PubMed

Coca, Mircea; Tecle, Nahom; Amde, Wendewessen; Mehta, Ankur

2017-08-23

We report a case of combined central retinal vein occlusion and branch retinal artery occlusion. A previously healthy 47-year-old male presented with decreased vision in the right eye after completing a half marathon. A fundus exam and retinal imaging revealed a combined central retinal vein and branch retinal artery occlusion. In the present report, we review the literature and discuss the possible mechanisms behind combined retinal vessel occlusions. To our knowledge, this is the first reported case of combined central retinal vein occlusion and branch retinal artery occlusion following intense exercise.

Combined Central Retinal Vein and Branch Retinal Artery Occlusion Post Intense Physical Activity

PubMed Central

Tecle, Nahom; Amde, Wendewessen; Mehta, Ankur

2017-01-01

We report a case of combined central retinal vein occlusion and branch retinal artery occlusion. A previously healthy 47-year-old male presented with decreased vision in the right eye after completing a half marathon. A fundus exam and retinal imaging revealed a combined central retinal vein and branch retinal artery occlusion. In the present report, we review the literature and discuss the possible mechanisms behind combined retinal vessel occlusions. To our knowledge, this is the first reported case of combined central retinal vein occlusion and branch retinal artery occlusion following intense exercise. PMID:29067224

Retinal Thickening and Photoreceptor Loss in HIV Eyes without Retinitis.

PubMed

Arcinue, Cheryl A; Bartsch, Dirk-Uwe; El-Emam, Sharif Y; Ma, Feiyan; Doede, Aubrey; Sharpsten, Lucie; Gomez, Maria Laura; Freeman, William R

2015-01-01

To determine the presence of structural changes in HIV retinae (i.e., photoreceptor density and retinal thickness in the macula) compared with age-matched HIV-negative controls. Cohort of patients with known HIV under CART (combination Antiretroviral Therapy) treatment were examined with a flood-illuminated retinal AO camera to assess the cone photoreceptor mosaic and spectral-domain optical coherence tomography (SD-OCT) to assess retinal layers and retinal thickness. Twenty-four eyes of 12 patients (n = 6 HIV-positive and 6 HIV-negative) were imaged with the adaptive optics camera. In each of the regions of interest studied (nasal, temporal, superior, inferior), the HIV group had significantly less mean cone photoreceptor density compared with age-matched controls (difference range, 4,308-6,872 cones/mm2). A different subset of forty eyes of 20 patients (n = 10 HIV-positive and 10 HIV-negative) was included in the retinal thickness measurements and retinal layer segmentation with the SD-OCT. We observed significant thickening in HIV positive eyes in the total retinal thickness at the foveal center, and in each of the three horizontal B-scans (through the macular center, superior, and inferior to the fovea). We also noted that the inner retina (combined thickness from ILM through RNFL to GCL layer) was also significantly thickened in all the different locations scanned compared with HIV-negative controls. Our present study shows that the cone photoreceptor density is significantly reduced in HIV retinae compared with age-matched controls. HIV retinae also have increased macular retinal thickness that may be caused by inner retinal edema secondary to retinovascular disease in HIV. The interaction of photoreceptors with the aging RPE, as well as possible low-grade ocular inflammation causing diffuse inner retinal edema, may be the key to the progressive vision changes in HIV-positive patients without overt retinitis.

Mechanism of metabolic stroke and spontaneous cerebral hemorrhage in glutaric aciduria type I

PubMed Central

2014-01-01

Background Metabolic stroke is the rapid onset of lasting central neurological deficit associated with decompensation of an underlying metabolic disorder. Glutaric aciduria type I (GA1) is an inherited disorder of lysine and tryptophan metabolism presenting with metabolic stroke in infancy. The clinical presentation includes bilateral striatal necrosis and spontaneous subdural and retinal hemorrhages, which has been frequently misdiagnosed as non-accidental head trauma. The mechanisms underlying metabolic stroke and spontaneous hemorrhage are poorly understood. Results Using a mouse model of GA1, we show that metabolic stroke progresses in the opposite sequence of ischemic stroke, with initial neuronal swelling and vacuole formation leading to cerebral capillary occlusion. Focal regions of cortical followed by striatal capillaries are occluded with shunting to larger non-exchange vessels leading to early filling and dilation of deep cerebral veins. Blood–brain barrier breakdown was associated with displacement of tight-junction protein Occludin. Conclusion Together the current findings illuminate the pathophysiology of metabolic stroke and vascular compromise in GA1, which may translate to other neurometabolic disorders presenting with stroke. PMID:24468193

Mechanism of metabolic stroke and spontaneous cerebral hemorrhage in glutaric aciduria type I.

PubMed

Zinnanti, William J; Lazovic, Jelena; Housman, Cathy; Antonetti, David A; Koeller, David M; Connor, James R; Steinman, Lawrence

2014-01-27

Metabolic stroke is the rapid onset of lasting central neurological deficit associated with decompensation of an underlying metabolic disorder. Glutaric aciduria type I (GA1) is an inherited disorder of lysine and tryptophan metabolism presenting with metabolic stroke in infancy. The clinical presentation includes bilateral striatal necrosis and spontaneous subdural and retinal hemorrhages, which has been frequently misdiagnosed as non-accidental head trauma. The mechanisms underlying metabolic stroke and spontaneous hemorrhage are poorly understood. Using a mouse model of GA1, we show that metabolic stroke progresses in the opposite sequence of ischemic stroke, with initial neuronal swelling and vacuole formation leading to cerebral capillary occlusion. Focal regions of cortical followed by striatal capillaries are occluded with shunting to larger non-exchange vessels leading to early filling and dilation of deep cerebral veins. Blood-brain barrier breakdown was associated with displacement of tight-junction protein Occludin. Together the current findings illuminate the pathophysiology of metabolic stroke and vascular compromise in GA1, which may translate to other neurometabolic disorders presenting with stroke.

Accelerated ischemic vascular retinopathy after intravitreally injected bevacizumab for central retinal vein occlusion in elderly patients

PubMed Central

Isola, Vincenzo; Pece, Alfredo; Massironi, Claudio; Reposi, Simone; Dimastrogiovanni, Fabio

2013-01-01

Background: Ischemic changes in the retinal circulation are an uncommon but severe adverse vascular reaction to intravitreal bevacizumab (Avastin®, Genentech, San Francisco, CA, USA/Roche, Basel, Switzerland) for central retinal vein occlusion (CRVO). In the two cases reported here, ischemic changes in the retina vasculature following intravitreal bevacizumab for CRVO were observed with the aim of describing the clinical and angiographic features of these changes. Methods: Two elderly patients with recent-onset CRVO received one off-label intravitreal injection of bevacizumab 0.05 mL/1.25 mg. Results: In Case 1, the patient’s pre-treatment visual acuity was 20/400. At 3 weeks post injection, the patient could count fingers at a distance of 1 ft (30 cm) and fluorescein angiography showed reduction in intraretinal hemorrhages and areas of retinal non-perfusion. However, at 6 weeks these were markedly increased compared with those seen in the photograph taken 3 weeks after treatment. In Case 2, the patient’s pre-treatment visual acuity was 20/200. At 1 month post injection, vision had decreased to 20/400 and fluorescein angiography showed severe macular ischemia with a remarkable capillary dropout throughout the macula. Conclusion: Ischemic retinal injury may be an uncommon but severe adverse vascular reaction to intravitreal bevacizumab for CRVO. Although progression of retinal ischemia in CRVO could be observed shortly after intravitreal bevacizumab, whether this is a drug- or procedure-related effect or part of the natural history of the condition remains uncertain. PMID:23467497

Retinal detachment

PubMed Central

2014-01-01

Introduction Rhegmatogenous retinal detachment (RRD) is the most common form of retinal detachment, where a retinal 'break' allows the ingress of fluid from the vitreous cavity to the subretinal space, resulting in retinal separation. It occurs in about 1 in 10,000 people a year. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of different surgical interventions in people with rhegmatogenous retinal detachment? What are the effects of interventions to treat proliferative vitreoretinopathy occurring as a complication of retinal detachment or previous treatment for retinal detachment? We searched: Medline, Embase, The Cochrane Library, and other important databases up to September 2013 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 14 studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review, we present information relating to the effectiveness and safety of the following interventions: corticosteroids, daunorubicin, fluorouracil plus low molecular weight heparin, pneumatic retinopexy, scleral buckling, short-acting or long-acting gas tamponade, silicone oil tamponade, and vitrectomy. PMID:24807890

Metastatic B-cell lymphoma masquerading as infectious retinitis and vasculitis.

PubMed

Say, Emil Anthony T; Knupp, Charles L; Gertsch, Kevin R; Chavala, Sai H

2012-06-01

Intraocular lymphoma is a rare ocular malignancy that may occur in the retina or the uvea. Retina or vitreoretinal lymphoma accounts for the majority of cases and is often secondary to diffuse large B-cell lymphoma. In the present study, a 66-year-old Caucasian male with a history of Waldenstrom's macroglobulinemia with diffuse large B-cell lymphoma, presented with blurred vision in the left eye one month following cycle 4 of an R-CHOP regimen. At the time of onset, the patient was being treated for bacterial pneumonia. Visual acuity was 20/25 in his right eye (OD) and 20/30 in the left (OS). Ophthalmologic examination showed intraretinal white infiltrates associated with hemorrhage in the superotemporal midperiphery of the retina and vitritis OS. Initial diagnostic considerations included infectious (cytomegalovirus retinitis, syphilis, toxoplasmosis, tuberculosis), inflammatory (retinal vasculitis associated with autoimmune disease or hypercoagulable states) or malignant (intraocular lymphoma) diseases. The patient did not respond to intravitreal injection of foscarnet and oral valgancyclovir. Systemic work-up and aqueous fluid biopsy were inconclusive. Diagnostic vitrectomy yielded inconclusive results and the patient continued to have progressive loss of vision. A repeat diagnostic vitrectomy with retinal and subretinal biopsy confirmed large B cells consistent with metastatic B-cell lymphoma. A concomitant PET/CT scan was performed that revealed bilateral new pulmonary nodules resulting in additional chemotherapy. Our case shows the diagnostic dilemmas in patients with systemic lymphoma and the possible role of concurrent systemic restaging in patients with ocular complaints, even when in systemic remission.

Recurrence of retinal vein thrombosis with Pycnogenol® or Aspirin® supplementation: a registry study.

PubMed

Rodriguez, P; Belcaro, G; Dugall, M; Hu, S; Luzzi, R; Ledda, A; Ippolito, E; Corsi, M; Ricci, A; Feragalli, B; Cornelli, U; Gizzi, C; Hosoi, M

2015-09-01

The aim of this study was to use Pycnogenol® to reduce the recurrence of retinal vein thrombosis (RVT) after a first episode. Pycnogenol® is an anti-inflammatory, anti-edema and an antiplatelet agent with a "mild" antithrombotic activity. The registry, using Pycnogenol® was aimed at reducing the number of repeated episodes of RVT. Possible management options--chosen by patients--were: standard management; standard management + oral Aspirin® 100 mg once/day (if there were no tolerability problems before admission); standard management + Pycnogenol® two 50 mg capsules per day (for a total of 100 mg/day). Number of subjects, age, sex, distribution, percentage of smokers, and vision were comparable. Recurrent RVT was seen in 17.39% of controls and in 3.56% of subjects supplemented with Pycnogenol® (P<0.05 vs. controls). There was RVT in 15.38% of the subjects using Aspirin®. The incidence of RVT was 4.88 times higher with standard management in comparison with the supplement group and 4.32 lower with Pycnogenol® supplementation in comparison with Aspirin®. Vision level was better with Pycnogenol® (20/25 at nine months; P<0.05). With Pycnogenol®, edema at the retinal level was also significantly reduced compared to the other groups. Pycnogenol® has a very good safety profile. In the Aspirin® group 26 completed 9 months and 6 subjects dropped out for tolerability problems. In the Aspirin® group, 2 minor, subclinical, retinal, hemorrhagic episodes during the follow-up were observed (2 subjects out of 26, equivalent to 7.69%). This pilot registry indicates that Pycnogenol® seems to reduce the recurrence of RVT without side effects. It does not induce new hemorrhagic episodes that may be theoretically linked to the use of Aspirin® (or other antiplatelets). Larger studies should be planned involving a wider range of conditions, diseases and risk factors associated to RVT and to its recurrence.

[Retinal detachment in HIV-infected patients with cytomegalovirus retinitis].

PubMed

Onishchenko, A L; Kolbasko, A V; Tatarnikova, G N; Grebenchuk, O S

2014-01-01

The authors present their own clinical experience in three HIV-infected patients with cytomegalovirus retinitis aged from 8 to 36 years. Detailed analysis of the results of physical and laboratory examinations is provided. Given short life expectancy for these patients, the authors pose a deontological question as to whether or not active treatment of retinal detachment in patients with AIDS and CMV retinitis is reasonable.

Evaluation of hyaloid-retinal relationship during triamcinolone-assisted vitrectomy for primary rhegmatogenous retinal detachment.

PubMed

Sundar, Dheepak; Takkar, Brijesh; Venkatesh, Pradeep; Chawla, Rohan; Temkar, Shreyas; Azad, Shorya Vardhan; Vohra, Rajpal

2018-03-01

To determine hyaloid-retinal relationship in primary rhegmatogenous retinal detachment during vitreous surgery. This is a prospective, interventional study of patients (n = 72) undergoing triamcinolone-assisted 25G vitreous surgery for primary rhegmatogenous retinal detachment. Hyaloid-retinal relationship was noted intraoperatively to identify regions and patterns of firm attachment and was classified into subgroups. Analysis was done to determine association between hyaloid-retinal relationship patterns and preoperative findings: posterior vitreous detachment, proliferative vitreoretinopathy, type of retinal tear, the presence of peripheral degenerations, and postoperative outcomes. Three patterns of hyaloid-retinal relationship were identified: type1 (complete absence of posterior vitreous detachment (21%)), type 2 (incomplete posterior vitreous detachment (47%)) and type 3 (complete posterior vitreous detachment (32%)). Posterior vitreous detachment in some form was present in 84% of the cases with retinal tears as the causative break but none of the cases with retinal holes (p < 0.001). None of the cases with vitreoretinal degeneration had complete posterior vitreous detachment (p = 0.001). 69% of proliferative vitreoretinopathy-C cases had type 1 hyaloid-retinal relationship as compared to 11% cases with no proliferative vitreoretinopathy (p < 0.001). Proliferative vitreoretinopathy-related anatomical failure was seen in 7.5%, and 80% of these eyes with recurrent RD had type 1 hyaloid-retinal relationship (p<0.001). Nearly half the patients diagnosed as complete posterior vitreous detachment preoperatively were found to have incomplete posterior vitreous detachment intraoperatively. Majority of the cases with rhegmatogenous retinal detachment have some form of strong vitreoretinal adhesion. Hyaloid-retinal relationship varies with types of retinal breaks, retinal degeneration, and proliferative vitreoretinopathy. Intraoperative hyaloid-retinal relationship is

Intraocular Hemorrhages and Retinopathy of Prematurity in the Telemedicine Approaches to Evaluating Acute-Phase Retinopathy of Prematurity (e-ROP) Study.

PubMed

Daniel, Ebenezer; Ying, Gui-Shuang; Siatkowski, R Michael; Pan, Wei; Smith, Eli; Quinn, Graham E

2017-03-01

To describe the clinical characteristics of intraocular hemorrhages (IOHs) in infants in the Telemedicine Approaches to Evaluating Acute-Phase Retinopathy of Prematurity (e-ROP) Study and to evaluate their potential use for prediction of disease severity. Secondary data analysis from a prospective study. Preterm infants with birth weight (BW) ≤1250 g. Infants underwent serial digital retinal imaging in both eyes starting at 32 weeks' postmenstrual age. Nonphysician trained readers (TRs) evaluated all image sets from eyes that ever had IOHs documented on image evaluation or eye examination for the presence, location, type, area, and relation of the IOH to the junction between vascularized and avascular retina. Associations of IOH with demographic and neonatal factors, and with the presence and severity of retinopathy of prematurity (ROP) were investigated by univariate and multivariate analyses. Sensitivity and specificity of the telemedicine system for detecting referral-warranted ROP (RW-ROP) were calculated with and without incorporating hemorrhage into the standardized grading protocol. Retinal and vitreous hemorrhage. Among 1239 infants (mean [standard deviation] BW = 864 [212] g; gestational age [GA] = 27 [2.2] weeks) who underwent an average of 3.2 imaging sessions, 22% had an IOH in an eye on at least 1 of the e-ROP visits. Classification of IOH was preretinal (57%), blot (57%), dot (38%), flame-shaped (16%), and vitreous (8%); most IOHs were unilateral (70%). The IOH resolved in 35% of eyes by the next imaging session and in the majority (76%) of cases by 8 weeks after initial detection. Presence of IOH was inversely associated with BW and GA and significantly associated (P < 0.0001) with the presence and severity of ROP (BW and GA adjusted odds ratios [ORs] of 2.46 for any ROP, 2.88 for stage 3, and 3.19 for RW-ROP). Incorporating IOH into the grading protocol minimally altered the sensitivity of the system (94% vs. 95%). Approximately 1 in 5 preterm

Hemorrhagic Stroke

MedlinePlus

A stroke is a medical emergency. There are two types - ischemic and hemorrhagic. Hemorrhagic stroke is the less common type. It happens when ... an artery wall that breaks open. Symptoms of stroke are Sudden numbness or weakness of the face, ...

Diosmin alleviates retinal edema by protecting the blood-retinal barrier and reducing retinal vascular permeability during ischemia/reperfusion injury.

PubMed

Tong, Nianting; Zhang, Zhenzhen; Zhang, Wei; Qiu, Yating; Gong, Yuanyuan; Yin, Lili; Qiu, Qinghua; Wu, Xingwei

2013-01-01

Retinal swelling, leading to irreversible visual impairment, is an important early complication in retinal ischemia/reperfusion (I/R) injury. Diosmin, a naturally occurring flavonoid glycoside, has been shown to have antioxidative and anti-inflammatory effects against I/R injury. The present study was performed to evaluate the retinal microvascular protective effect of diosmin in a model of I/R injury. Unilateral retinal I/R was induced by increasing intraocular pressure to 110 mm Hg for 60 min followed by reperfusion. Diosmin (100 mg/kg) or vehicle solution was administered intragastrically 30 min before the onset of ischemia and then daily after I/R injury until the animals were sacrificed. Rats were evaluated for retinal functional injury by electroretinogram (ERG) just before sacrifice. Retinas were harvested for HE staining, immunohistochemistry assay, ELISA, and western blotting analysis. Evans blue (EB) extravasation was determined to assess blood-retinal barrier (BRB) disruption and the structure of tight junctions (TJ) was examined by transmission electron microscopy. Diosmin significantly ameliorated the reduction of b-wave, a-wave, and b/a ratio in ERG, alleviated retinal edema, protected the TJ structure, and reduced EB extravasation. All of these effects of diosmin were associated with increased zonular occluden-1 (ZO-1) and occludin protein expression and decreased VEGF/PEDF ratio. Maintenance of TJ integrity and reduced permeability of capillaries as well as improvements in retinal edema were observed with diosmin treatment, which may contribute to preservation of retinal function. This protective effect of diosmin may be at least partly attributed to its ability to regulate the VEGF/PEDF ratio.

Retinitis pigmentosa

MedlinePlus

... this page: //medlineplus.gov/ency/article/001029.htm Retinitis pigmentosa To use the sharing features on this page, please enable JavaScript. Retinitis pigmentosa is an eye disease in which there is ...

CMV retinitis

MedlinePlus

Cytomegalovirus (CMV) retinitis is a viral infection of the retina of the eye resulting in inflammation. ... CMV retinitis is caused by a member of a group of herpes-type viruses. Infection with CMV ...

Retinitis Pigmentosa.

ERIC Educational Resources Information Center

Carr, Ronald E.

1979-01-01

The author describes the etiology of retinitis pigmentosa, a visual dysfunction which results from progressive loss of the retinal photoreceptors. Sections address signs and symptoms, ancillary findings, heredity, clinical diagnosis, therapy, and research. (SBH)

Laser-induced retinal injury thresholds: variation with retinal irradiated area

NASA Astrophysics Data System (ADS)

Lund, David J.; Schulmeister, Karl; Seiser, Bernhard; Edthofer, Florian

2005-04-01

The retinal injury threshold for exposure to a laser source varies as a function of the irradiated area on the retina. Currently accepted guidelines for the safe use of lasers provide that the MPE will increase as the diameter of the irradiated area for retinal diameters between 25 mm and 1700 mm, based on the ED50 data available in the late 1970s. Recent studies by Zuclich and Lund produced data showing that the ED50 for ns-duration exposures at 532 nm and ms duration exposures at 590 nm varied as the square of the diameter of the irradiated area on the retina. This paper will discuss efforts to resolve the disagreement between the new data and the earlier data though an analysis of all accessible data relating the retinal injury threshold to the diameter of the incident beam on the retina and through simulations using computer models of laser-induced injury. The results show that the retinal radiant exposure required to produce retinal injury is a function of both exposure duration and retinal irradiance diameter and that the current guidelines for irradiance diameter dependence do not accurately reflect the variation of the threshold data.

Uncontrolled Hemorrhage Differs From Volume- or Pressure-Matched Controlled Hemorrhage in Swine

DTIC Science & Technology

2007-10-01

differences between these models, we evaluated the relationship between blood volume loss and blood pressure in controlled versus uncontrolled hemorrhage...aortotomy; (2) group P, controlled hemorrhage matched to the blood pressure profile of group U; or (3) group V, controlled hemorrhage matched to the...hemorrhage and received no fluid resuscitation. Group U resulted in a blood loss of 17.6 T 0.7 mL kgj1 and a reduction in blood pressure to 28 T 3 mmHg at

[Retinal vasculopathy with cerebral leukoencephalopathy carrying TREX1 mutation diagnosed by the intracranial calcification: a case report].

PubMed

Komaki, Ryouhei; Ueda, Takehiro; Tsuji, Yukio; Miyawaki, Toko; Kusuhara, Sentaro; Hara, Shigeo; Toda, Tatsushi

2018-02-28

A 40-year-old woman with renal dysfunction for 2 years was admitted to our hospital suffering from a headache. Family history revealed that her mother had a headache, renal dysfunction, and brain infarction in younger age. She had a retinal hemorrhage, a retinal atrophy, pitting edema in her lower extremities. Her neurological findings were unremarkable. Brain imaging showed multiple white matter lesions accompanied with calcifications and slightly enhancement. Kidney biopsy showed the thrombotic microangiopathy, Gene analysis demonstrated a causative mutation in three-prime repair exonuclease-1 (TREX1) gene, c.703_704insG (p.Val235GlyfsX6), thereby we diagnosed her as retinal vasculopathy with cerebral leukoencephalopathy (RVCL). RVCL is an autosomal dominant condition caused by C-terminal frame-shift mutation in TREX1. TREX1 protein is a major 3' to 5' DNA exonuclease, which are important in DNA repair. While TREX1 mutations identified in Aicardi-Goutieres syndrome patients lead to a reduction of enzyme activity, it is suggested that mutations in RVCL alter an intracellular location of TREX1 protein. There are no treatments based evidences in RVCL. We administered cilostazol to protect endothelial function, and her brain lesions and renal function have not become worse for 10 months after. It is necessary to consider RVCL associated with TREX1 mutation if a patient has retinal lesions, white matter lesions accompanied with calcifications, and multiple organ dysfunction.

Differences in Neuropeptide Y Secretion Between Intracerebral Hemorrhage and Aneurysmal Subarachnoid Hemorrhage.

PubMed

Schebesch, Karl-M; Bründl, Elisabeth; Schödel, Petra; Hochreiter, Andreas; Scheitzach, Judith; Bele, Sylvia; Brawanski, Alexander; Störr, Eva-M; Lohmeier, Anette; Proescholdt, Martin

2017-07-01

Neuropeptide Y (NPY) is one of the most potent endogenous vasoconstrictors, and its contribution to the multifactorial cascade of cerebral vasospasm due to nontraumatic subarachnoid hemorrhage (SAH) is not yet fully understood. This experimental study compared the hemorrhage-specific course of NPY secretion into cerebrospinal fluid (CSF) and into plasma between 2 groups: patients with SAH and patients with basal ganglia hemorrhage (BGH) or cerebellar hemorrhage (CH) over the first 10 days after hemorrhage. Seventy-nine patients were prospectively included: SAH patients (n=66) (historic population) and intracerebral hemorrhage patients (n=13). All patients received an external ventricular drain within 24 hours of the onset of bleeding. CSF and plasma were drawn daily from day 1 to day 10. The levels of NPY were determined by means of competitive enzyme immunoassay. The CSF samples of 29 patients (historic population) who had undergone spinal anesthesia due to orthopedic surgery served as the control group. NPY levels in CSF were significantly higher in the 2 hemorrhage groups than in the control group. However, the 2 hemorrhage groups showed significant differences in NPY levels in CSF (SAH mean, 0.842 ng/mL vs. BGH/CH mean, 0.250 ng/mL; P<0.001) as well as in the course of NPY secretion into CSF over the 10-day period. NPY levels in plasma did not differ significantly among SAH, BGH/CH, and controls. Our findings support the hypothesis that excessive release of NPY into CSF but not into plasma is specific to aneurysmal SAH in the acute period of 10 days after hemorrhage. In BGH/CH, CSF levels of NPY were also increased, but the range was much lower.

Retinal Detachment Associated with AIDS-Related Cytomegalovirus Retinitis: Risk Factors in a Resource-Limited Setting

PubMed Central

Yen, Michael; Chen, Jenny; Ausayakhun, Somsanguan; Kunavisarut, Paradee; Vichitvejpaisal, Pornpattana; Ausayakhun, Sakarin; Jirawison, Choeng; Shantha, Jessica; Holland, Gary N; Heiden, David; Margolis, Todd P; Keenan, Jeremy D

2014-01-01

Purpose To determine risk factors predictive of retinal detachment in patients with cytomegalovirus (CMV) retinitis in a setting with limited access to ophthalmic care. Design Case-control study. Methods Sixty-four patients with CMV retinitis and retinal detachment were identified from the Ocular Infectious Diseases and Retina Clinics at Chiang Mai University. Three control patients with CMV retinitis but no retinal detachment were selected for each case, matched by calendar date. The medical records of each patient were reviewed, with patient-level and eye-level features recorded for the clinic visit used to match cases and controls, and also for the initial clinic visit at which CMV retinitis was diagnosed. Risk factors for retinal detachment were assessed separately for each of these time points using multivariate conditional logistic regression models that included 1 eye from each patient. Results Patients with a retinal detachment were more likely than controls to have low visual acuity (OR, 1.24 per line of worse vision on the logMAR scale; 95%CI, 1.16-1.33) and bilateral disease (OR, 2.12; 95%CI, 0.92-4.90). Features present at the time of the initial diagnosis of CMV retinitis that predicted subsequent retinal detachment included bilateral disease (OR, 2.68; 95%CI, 1.18-6.08) and lesion size (OR, 2.64 per 10% increase in lesion size; 95%CI, 1.41-4.94). Conclusion Bilateral CMV retinitis and larger lesion sizes, each of which is a marker of advanced disease, were associated with subsequent retinal detachment. Earlier detection and treatment may reduce the likelihood that patients with CMV retinitis develop a retinal detachment. PMID:25448999

Retinal detachment associated with AIDS-related cytomegalovirus retinitis: risk factors in a resource-limited setting.

PubMed

Yen, Michael; Chen, Jenny; Ausayakhun, Somsanguan; Kunavisarut, Paradee; Vichitvejpaisal, Pornpattana; Ausayakhun, Sakarin; Jirawison, Choeng; Shantha, Jessica; Holland, Gary N; Heiden, David; Margolis, Todd P; Keenan, Jeremy D

2015-01-01

To determine risk factors predictive of retinal detachment in patients with cytomegalovirus (CMV) retinitis in a setting with limited access to ophthalmic care. Case-control study. Sixty-four patients with CMV retinitis and retinal detachment were identified from the Ocular Infectious Diseases and Retina Clinics at Chiang Mai University. Three control patients with CMV retinitis but no retinal detachment were selected for each case, matched by calendar date. The medical records of each patient were reviewed, with patient-level and eye-level features recorded for the clinic visit used to match cases and controls, and also for the initial clinic visit at which CMV retinitis was diagnosed. Risk factors for retinal detachment were assessed separately for each of these time points using multivariate conditional logistic regression models that included 1 eye from each patient. Patients with a retinal detachment were more likely than controls to have low visual acuity (odds ratio [OR], 1.24 per line of worse vision on the logMAR scale; 95% confidence interval [CI], 1.16-1.33) and bilateral disease (OR, 2.12; 95% CI, 0.92-4.90). Features present at the time of the initial diagnosis of CMV retinitis that predicted subsequent retinal detachment included bilateral disease (OR, 2.68; 95% CI, 1.18-6.08) and lesion size (OR, 2.64 per 10% increase in lesion size; 95% CI, 1.41-4.94). Bilateral CMV retinitis and larger lesion sizes, each of which is a marker of advanced disease, were associated with subsequent retinal detachment. Earlier detection and treatment may reduce the likelihood that patients with CMV retinitis develop a retinal detachment. Copyright © 2015 Elsevier Inc. All rights reserved.

A Rare Complication After Septoplasty: Visual Loss Due to Right Retinal Artery Spasm.

PubMed

Günay, Celal; Altin, Gökhan; Kersin, Burak; Odabaşi, Mahmut

2018-03-01

Septoplasty is a commonly used procedure for correcting septal cartilage deformities. Hemorrhage, abscesses, scaling, adhesions, and scar tissue are often seen after the operation of the septoplasty, but temporary or permanent visual loss due to local anesthetic use has been reported very rarely in the literature. The authors also aimed to present a female patient with retinal artery spasm in the right eye after septoplasty in this article. A 27-year-old female patient was admitted to the authors' clinic with long-standing nasal obstruction and postnasal drip. There was no feature in her history and also no sign other than nasal septal deviation on physical examination. The patient was informed about the operation and the operation was planned. Emergency eye consultation was requested after the patient said that the right eye of the patient had never seen in the postoperative wake-up hall. Examination by an ophthalmologist; mild exotropia and total loss of vision in the right eye (including loss of light reflex) was detected. The light reaction in the affected eye was negative and indirect reaction was positive. After enlargement of the pupil, fundus examination revealed that the right posterior pole region (inside of the macula and vessel arches) was pale and no central retinal artery pulsation was observed. The patient was diagnosed with central retinal artery occlusion and emergency intervention was performed. The right eye massage, paracentesis, and hyperbaric oxygen therapy returned to the patient's visual function.

Cell Therapy Applications for Retinal Vascular Diseases: Diabetic Retinopathy and Retinal Vein Occlusion.

PubMed

Park, Susanna S

2016-04-01

Retinal vascular conditions, such as diabetic retinopathy and retinal vein occlusion, remain leading causes of vision loss. No therapy exists to restore vision loss resulting from retinal ischemia and associated retinal degeneration. Tissue regeneration is possible with cell therapy. The goal would be to restore or replace the damaged retinal vasculature and the retinal neurons that are damaged and/or degenerating from the hypoxic insult. Currently, various adult cell therapies have been explored as potential treatment. They include mesenchymal stem cells, vascular precursor cells (i.e., CD34+ cells, hematopoietic cells or endothelial progenitor cells), and adipose stromal cells. Preclinical studies show that all these cells have a paracrine trophic effect on damaged ischemic tissue, leading to tissue preservation. Endothelial progenitor cells and adipose stromal cells integrate into the damaged retinal vascular wall in preclinical models of diabetic retinopathy and ischemia-reperfusion injury. Mesenchymal stem cells do not integrate as readily but appear to have a primary paracrine trophic effect. Early phase clinical trials have been initiated and ongoing using mesenchymal stem cells or autologous bone marrow CD34+ cells injected intravitreally as potential therapy for diabetic retinopathy or retinal vein occlusion. Adipose stromal cells or pluripotent stem cells differentiated into endothelial colony-forming cells have been explored in preclinical studies and show promise as possible therapies for retinal vascular disorders. The relative safety or efficacy of these various cell therapies for treating retinal vascular disorders have yet to be determined.

Retinal Diseases

MedlinePlus

... You are here Home Listen Retinal Diseases Macular Degeneration Age-related macular degeneration (AMD) is a retinal degenerative disease that causes ... is the most common form of inherited juvenile macular degeneration. The progressive vision loss associated with Stargardt disease ...

Successful displacement of a traumatic submacular hemorrhage in a 13-year-old boy treated by vitrectomy, subretinal injection of tissue plasminogen activator and intravitreal air tamponade: a case report.

PubMed

Doi, Shinichiro; Kimura, Shuhei; Morizane, Yuki; Shiode, Yusuke; Hosokawa, Mio; Hirano, Masayuki; Hosogi, Mika; Fujiwara, Atsushi; Miyamoto, Kazuhisa; Shiraga, Fumio

2015-08-07

The natural course of submacular hemorrhage resulting from traumatic choroidal rupture generally has a poor outcome unless treated. The intravitreal injection of gas only or gas with recombinant tissue plasminogen activator (rt-PA) has been reported to be effective, but has also been reported to induce severe complications such as retinal detachment and vitreous hemorrhage. Recently, we reported a safe and effective procedure for treating submacular hemorrhage due to polypoidal choroidal vasculopathy (PCV) with a low dose of rt-PA. Here we report the application of this procedure to a case of traumatic submacular hemorrhage in a 13-year-old boy, which achieved a good visual outcome. A 13-year-old Japanese boy presented with a thick submacular hemorrhage in his left eye as a result of blunt trauma from being hit by a sinker. Best-corrected visual acuity (BCVA) was assessed as only able to perceive hand motions. We carried out a vitrectomy, subretinal injection of 4,000 IU rt-PA (6.9 μg) and air tamponade. The day after surgery, most of the submacular hemorrhage had moved to the inferior periphery. One month after the surgery, we observed cataract formation, thin remnants of the submacular hemorrhage and juxtafoveal choroidal rupture. We carried out cataract surgery and injected bevacizumab intravitreally to prevent the development of choroidal neovascularization. Two months after the second surgery, the submacular hemorrhage had totally disappeared and the patient had a BCVA of 20/40. Vitrectomy, subretinal injection of rt-PA, and intravitreal air tamponade may be a promising strategy for treating traumatic submacular hemorrhage in young patients.

Contribution of placenta accreta to the incidence of postpartum hemorrhage and severe postpartum hemorrhage.

PubMed

Mehrabadi, Azar; Hutcheon, Jennifer A; Liu, Shiliang; Bartholomew, Sharon; Kramer, Michael S; Liston, Robert M; Joseph, K S

2015-04-01

To quantify the contribution of placenta accreta to the rate of postpartum hemorrhage and severe postpartum hemorrhage. All hospital deliveries in Canada (excluding Quebec) for the years 2009 and 2010 (N=570,637) were included in a retrospective cohort study using data from the Canadian Institute for Health Information. Placenta accreta included placental adhesion to the uterine wall, musculature, and surrounding organs (accreta, increta, or percreta). Severe postpartum hemorrhage included postpartum hemorrhage with blood transfusion, hysterectomy, or other procedures to control bleeding (including uterine suturing and ligation or embolization of pelvic arteries). Rates, rate ratios, population-attributable fractions (ie, incidence of postpartum hemorrhage attributable to placenta accreta), and 95% confidence intervals (CIs) were estimated. Logistic regression was used to quantify associations between placenta accreta and risk factors. The incidence of placenta accreta was 14.4 (95% CI 13.4-15.4) per 10,000 deliveries (819 cases among 570,637 deliveries), whereas the incidence of placenta accreta with postpartum hemorrhage was 7.2 (95% CI 6.5-8.0) per 10,000 deliveries. Postpartum hemorrhage among women with placenta accreta was predominantly third-stage hemorrhage (41% of all cases). Although placenta accreta was strongly associated with postpartum hemorrhage (rate ratio 8.3, 95% CI 7.7-8.9), its low frequency resulted in a small population-attributable fraction (1.0%, 95% CI 0.93-1.16). However, the strong association between placenta accreta and postpartum hemorrhage with hysterectomy (rate ratio 286, 95% CI 226-361) resulted in a population-attributable fraction of 29.0% (95% CI 24.3-34.3). Placenta accreta is too infrequent to account for the recent temporal increase in postpartum hemorrhage but contributes substantially to the proportion of postpartum hemorrhage with hysterectomy.

Long-term safety of human retinal progenitor cell transplantation in retinitis pigmentosa patients.

PubMed

Liu, Yong; Chen, Shao Jun; Li, Shi Ying; Qu, Ling Hui; Meng, Xiao Hong; Wang, Yi; Xu, Hai Wei; Liang, Zhi Qing; Yin, Zheng Qin

2017-09-29

Retinitis pigmentosa is a common genetic disease that causes retinal degeneration and blindness for which there is currently no curable treatment available. Vision preservation was observed in retinitis pigmentosa animal models after retinal stem cell transplantation. However, long-term safety studies and visual assessment have not been thoroughly tested in retinitis pigmentosa patients. In our pre-clinical study, purified human fetal-derived retinal progenitor cells (RPCs) were transplanted into the diseased retina of Royal College of Surgeons (RCS) rats, a model of retinal degeneration. Based on these results, we conducted a phase I clinical trial to establish the safety and tolerability of transplantation of RPCs in eight patients with advanced retinitis pigmentosa. Patients were studied for 24 months. After RPC transplantation in RCS rats, we observed moderate recovery of vision and maintenance of the outer nuclear layer thickness. Most importantly, we did not find tumor formation or immune rejection. In the retinis pigmentosa patients given RPC injections, we also did not observe immunological rejection or tumorigenesis when immunosuppressive agents were not administered. We observed a significant improvement in visual acuity (P < 0.05) in five patients and an increase in retinal sensitivity of pupillary responses in three of the eight patients between 2 and 6 months after the transplant, but this improvement did not appear by 12 months. Our study for the first time confirmed the long-term safety and feasibility of vision repair by stem cell therapy in patients blinded by retinitis pigmentosa. WHO Trial Registration, ChiCTR-TNRC-08000193 . Retrospectively registered on 5 December 2008.

N-Terminal Pro-B-Type Natriuretic Peptide Is Related to Retinal Microvascular Damage: The Rotterdam Study.

PubMed

Mutlu, Unal; Ikram, M Arfan; Hofman, Albert; de Jong, Paulus T V M; Klaver, Caroline C W; Ikram, M Kamran

2016-08-01

N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a marker of cardiac dysfunction and has been linked to various indices of large vessel disease. However, it remains unclear whether NT-proBNP also relates to microvascular damage. In a community-dwelling population, we studied the association between NT-proBNP and retinal microvascular damage. From the population-based Rotterdam Study, we included 8437 participants (mean age 64.1 years and 59% women) without a history of cardiovascular disease, with NT-proBNP data and gradable retinal images. NT-proBNP serum levels were measured using an immunoassay. Retinopathy signs, that is, exudates, microaneurysms, cotton wool spots, and dot/blot hemorrhages, present on fundus photographs were graded in the total study population; retinal vascular calibers, that is, arteriolar and venular calibers, were semiautomatically measured in a subsample (n=2763) of the study population. We conducted cross-sectional analyses on the association between NT-proBNP and retinal microvascular damage using logistic and linear regression models, adjusting for age, sex, and cardiovascular risk factors. We found that NT-proBNP was associated with the presence of retinopathy (adjusted odds ratio [95% confidence interval] per SD increase in natural log-transformed NT-proBNP: 1.14 [1.03-1.27]). We also found that higher NT-proBNP was associated with narrower arteriolar calibers (adjusted mean difference in arteriolar caliber per SD increase in natural log-transformed NT-proBNP: -0.89 µm [-1.54 to -0.24]). This association remained unchanged after excluding participants with retinopathy signs. In participants free of clinical cardiovascular disease, higher levels of NT-proBNP are associated with retinal microvascular damage, suggesting a potential role for NT-proBNP as marker for small vessel disease. © 2016 American Heart Association, Inc.

Rickettsial retinitis: acute unilateral vision loss with cystoid macular edema and stellate maculopathy.

PubMed

Gerwin, Brett; Read, Russell W; Taylor, Wayne

2011-01-01

To report on the presentation and treatment of a patient with infectious posterior segment uveitis because of infection with Rickettsia rickettsii. Interventional case report. We conducted a retrospective chart review of a 39-year-old man who presented with a history of acute vision loss in his right eye over a 6-day period. Vision at presentation in the involved eye was 2/200, with mild conjunctival injection, trace anterior chamber cell, moderate vitritis, localized retinitis and retinal hemorrhages, and severe macular edema. The left eye had 20/20 vision and was normal on examination. History was notable for a tick bite followed by high fevers, 1 month before presentation, at which time his family physician diagnosed mononucleosis syndrome with low platelets. A serum Rickettsia rickettsii test was positive. He was treated with oral doxycycline followed by corticosteroids. Vision gradually improved to 20/20 with minimal residual metamorphopsia. Only ten cases of Rocky Mountain spotted fever-related uveitis have been reported. The current case is unique because of the delayed onset of ophthalmic complications after the tick bite, its unilateral nature, dramatic improvement in acuity after treatment, and lack of associated rash.

Intracerebral hemorrhage (image)

MedlinePlus

Intracerebral hemorrhage may be caused by trauma (brain injury) or abnormalities of the blood vessels (aneurysm or angioma), but it is most commonly associated with high blood pressure (hypertensive intracerebral hemorrhage).

Retinal pigmentary changes in chronic uveitis mimicking retinitis pigmentosa.

PubMed

Sevgi, D Damla; Davoudi, Samaneh; Comander, Jason; Sobrin, Lucia

2017-09-01

To present retinal pigmentary changes mimicking retinitis pigmentosa (RP) as a finding of advanced uveitis. We retrospectively reviewed charts of patients without a family history of inherited retinal degenerations who presented with retinal pigment changes and signs of past or present intraocular inflammation. Comprehensive eye examination including best-corrected visual acuity, slit-lamp examination and dilated fundus examination was performed on all patients in addition to color fundus photography, optical coherence tomography, fluorescein angiography (FA), and full-field electroretinogram testing. We identified five patients with ages ranging from 33 to 66 years, who presented with RP-like retinal pigmentary changes which were eventually attributed to longstanding uveitis. The changes were bilateral in three cases and unilateral in two cases. Four of five cases presented with active inflammation, and the remaining case showed evidence of active intraocular inflammation during follow-up. This study highlights the overlapping features of advanced uveitis and RP including the extensive pigmentary changes. Careful review of possible past uveitis history, detailed examination of signs of past or present inflammation and ancillary testing, with FA often being most helpful, are required for the correct diagnosis. This is important, because intervention can prevent further damage if the cause of the pigmentary changes is destructive inflammation.

Viral Hemorrhagic Fevers

MedlinePlus

... Controls Cancel Submit Search the CDC Viral Hemorrhagic Fevers (VHFs) Note: Javascript is disabled or is not ... visit this page: About CDC.gov . Viral Hemorrhagic Fevers (VHFs) Virus Families Arenaviruses Old World/New World ...

Chronic retinal necrosis: cytomegalovirus necrotizing retinitis associated with panretinal vasculopathy in non-HIV patients.

PubMed

Schneider, Eric W; Elner, Susan G; van Kuijk, Frederik J; Goldberg, Naomi; Lieberman, Ronni M; Eliott, Dean; Johnson, Mark W

2013-10-01

To characterize a unique cytomegalovirus (CMV)-associated retinopathy in patients with limited immune dysfunction. Retrospective observational case series. CMV was confirmed as the pathogenic agent via polymerase chain reaction analysis of aqueous or vitreous humor samples or via immunohistochemical analysis of retinal biopsy specimens. Five non-HIV patients with granular necrotizing retinitis, vitritis, and severe occlusive vasculopathy were identified. Patient histories all suggested a basis for limited immune dysfunction including advanced age (n = 4), diabetes mellitus (n = 4), and noncytotoxic immunotherapy (n = 3). Diagnosis of CMV retinitis was delayed in all cases and patients received either no antiviral therapy (n = 2) or incorrect antiviral therapy (n = 3) for presumed herpes simplex/varicella zoster-related acute retinal necrosis. Retinitis subsequently regressed in all cases with introduction of systemic ganciclovir/valganciclovir (n = 5) and/or intravitreal foscarnet (n = 2). Four of five patients developed neovascularization because of extensive retinal ischemia. The clinical expression of CMV-associated retinopathy is strongly related to immune status. In patients with limited immune dysfunction, a mixed clinical picture of intraocular inflammation with panretinal occlusive vasculopathy, more characteristic of acute retinal necrosis, and peripheral slowly progressive granular retinitis, more characteristic of classic CMV retinitis, is observed. Recognition of this atypical clinical presentation, which the authors term chronic retinal necrosis, should prompt molecular testing for CMV to determine the appropriate antiviral therapy. Consideration should also be given to prophylactic panretinal photocoagulation in such eyes, given the high risk of neovascular complications.

Retinal vasculopathy in patients with systemic lupus erythematosus.

PubMed

Gao, N; Li, M T; Li, Y H; Zhang, S H; Dai, R P; Zhang, S Z; Zhao, L D; Wang, L; Zhang, F C; Zhao, Y; Zeng, X F

2017-10-01

A retrospective case control study was conducted in the Peking Union Medical College Hospital. Medical records were reviewed for demographic data, clinical features, laboratory results, systemic lupus erythematosus (SLE) disease activity evaluations, and ophthalmic examinations to investigate the clinical characteristics and significance of retinal vasculopathy (RV) in Chinese patients with systemic lupus erythematosus. The prevalence of RV was approximately 0.66% (35/5298) in SLE patients. A total of 60 eyes were involved. The ocular presentations included decrease of visual acuity (48/60, 80%), visual field loss (7/60, 11.7%), and diplopia (3/60, 5%). Ophthalmic fundoscopic examination revealed cotton-wool spots (30/60, 50%), retinal vascular attenuation (31/60, 51.6%), and hemorrhages (41/60, 68.3%). Retinal angiogram showed that 72.7% (16/22) eyes had vaso-occlusion. The ophthalmic episodes could occur at any stage of SLE duration, with a median of 12 months (0-168 months) following SLE onset. Twenty-one (35%) eyes did not recover, or even worsened, during hospital stay. RV was found to be significantly associated with neuropsychiatric lesions (51.4% vs. 21.3%, p = .005) and hematological disturbance (62.9% vs. 34.3%, p = .005). SLE patients with RV had significantly higher SLE disease activity index scores than controls (19.9 ± 0.9 vs. 10.2 ± 0.7, p < .001). An inverse association of anti-SSA antibody with RV was detected (34.3% vs. 67.1%, p = .001). Nervous system disturbance (odds ratio (OR) = 4.340, 95% confidence interval (CI) 1.438, 13.094, p = .009) and leukocytopenia (OR = 6.385, 95% CI 1.916, 21.278, p = .003) were independent risk factors, while anti-SSA antibody positivity (OR = 0.249, 95% CI 0.087, 0.710, p = .009) was a protective factor for RV in SLE patients. In certain cases, RV is a threatening condition for SLE patients presenting with clinical ocular manifestations. Ophthalmo

RETINAL DEEP CAPILLARY ISCHEMIA ASSOCIATED WITH AN OCCLUDED CONGENITAL RETINAL MACROVESSEL.

PubMed

Hasegawa, Taiji; Ogata, Nahoko

2017-01-01

To report the case of a patient with an occluded congenital retinal macrovessel accompanied by retinal deep capillary ischemia. A 38-year-old woman presented with a 2-day history of a paracentral scotoma of her right eye. Fundus photograph showed a dilated congenital retinal macrovessel with arteriovenous anastomosis, an intravascular white region indicating the thrombus at arteriovenous anastomotic region, and an area of retinal whitening temporal to the fovea. The spectral domain optical coherence tomography images through the area of retinal whitening showed a thickening and highly reflectivity at the level of the inner nuclear layer, which is likely due to the deep capillary ischemia. After 6 weeks, spectral domain optical coherence tomography images through the same area demonstrated a thinning and atrophy of only the inner nuclear layer, and the patient's paracentral scotoma persisted. Acute capillary hemodynamic changes caused deep capillary ischemia. The spectral domain optical coherence tomography showed a highly reflective lesion at the level of the inner nuclear layer in the acute phase.

Repetitive magnetic stimulation improves retinal function in a rat model of retinal dystrophy

NASA Astrophysics Data System (ADS)

Rotenstreich, Ygal; Tzameret, Adi; Levi, Nir; Kalish, Sapir; Sher, Ifat; Zangen, Avraham; Belkin, Michael

2014-02-01

Vision incapacitation and blindness associated with retinal dystrophies affect millions of people worldwide. Retinal degeneration is characterized by photoreceptor cell death and concomitant remodeling of remaining retinal cells. Repetitive Magnetic Stimulation (RMS) is a non-invasive technique that creates alternating magnetic fields by brief electric currents transmitted through an insulated coil. These magnetic field generate action potentials in neurons, and modulate the expression of neurotransmitter receptors, growth factors and transcription factors which mediate plasticity. This technology has been proven effective and safe in various psychiatric disorders. Here we determined the effect of RMS on retinal function in Royal College of Surgeons (RCS) rats, a model for retinal dystrophy. Four week-old RCS and control Spargue Dawley (SD) rats received sham or RMS treatment over the right eye (12 sessions on 4 weeks). RMS treatment at intensity of at 40% of the maximal output of a Rapid2 stimulator significantly increased the electroretinogram (ERG) b-wave responses by up to 6- or 10-fold in the left and right eye respectively, 3-5 weeks following end of treatment. RMS treatment at intensity of 25% of the maximal output did not significant effect b-wave responses following end of treatment with no adverse effect on ERG response or retinal structure of SD rats. Our findings suggest that RMS treatment induces delayed improvement of retinal functions and may induce plasticity in the retinal tissue. Furthermore, this non-invasive treatment may possibly be used in the future as a primary or adjuvant treatment for retinal dystrophy.

MULTIMODAL IMAGING OF SYPHILITIC MULTIFOCAL RETINITIS.

PubMed

Curi, Andre L; Sarraf, David; Cunningham, Emmett T

2015-01-01

To describe multimodal imaging of syphilitic multifocal retinitis. Observational case series. Two patients developed multifocal retinitis after treatment of unrecognized syphilitic uveitis with systemic corticosteroids in the absence of appropriate antibiotic therapy. Multimodal imaging localized the foci of retinitis within the retina in contrast to superficial retinal precipitates that accumulate on the surface of the retina in eyes with untreated syphilitic uveitis. Although the retinitis resolved after treatment with systemic penicillin in both cases, vision remained poor in the patient with multifocal retinitis involving the macula. Treatment of unrecognized syphilitic uveitis with corticosteroids in the absence of antitreponemal treatment can lead to the development of multifocal retinitis. Multimodal imaging, and optical coherence tomography in particular, can be used to distinguish multifocal retinitis from superficial retinal precipitates or accumulations.

Bilateral patching in retinal detachment: fluid mechanics and retinal "settling".

PubMed

Foster, William J

2011-07-20

When a patient suffers a retinal detachment and surgery is delayed, it is known clinically that bilaterally patching the patient may allow the retina to partially reattach or "settle." Although this procedure has been performed since the 1860s, there is still debate as to how such a maneuver facilitates the reattachment of the retina. Finite element calculations using commercially available analysis software are used to elucidate the influence of reduction in eye movement caused by bilateral patching on the flow of subretinal fluid in a physical model of retinal detachment. It was found that by coupling fluid mechanics with structural mechanics, a physically consistent explanation of increased retinal detachment with eye movements can be found in the case of traction on the retinal hole. Large eye movements increase vitreous traction and detachment forces on the edge of the retinal hole, creating a subretinal vacuum and facilitating increased subretinal fluid. Alternative models, in which intraocular fluid flow is redirected into the subretinal space, are not consistent with these simulations. The results of these simulations explain the physical principles behind bilateral patching and provide insight that can be used clinically. In particular, as is known clinically, bilateral patching may facilitate a decrease in the height of a retinal detachment. The results described here provide a description of a physical mechanism underlying this technique. The findings of this study may aid in deciding whether to bilaterally patch patients and in counseling patients on pre- and postoperative care.

Laser-induced retinal damage thresholds for annular retinal beam profiles

NASA Astrophysics Data System (ADS)

Kennedy, Paul K.; Zuclich, Joseph A.; Lund, David J.; Edsall, Peter R.; Till, Stephen; Stuck, Bruce E.; Hollins, Richard C.

2004-07-01

The dependence of retinal damage thresholds on laser spot size, for annular retinal beam profiles, was measured in vivo for 3 μs, 590 nm pulses from a flashlamp-pumped dye laser. Minimum Visible Lesion (MVL)ED50 thresholds in rhesus were measured for annular retinal beam profiles covering 5, 10, and 20 mrad of visual field; which correspond to outer beam diameters of roughly 70, 160, and 300 μm, respectively, on the primate retina. Annular beam profiles at the retinal plane were achieved using a telescopic imaging system, with the focal properties of the eye represented as an equivalent thin lens, and all annular beam profiles had a 37% central obscuration. As a check on experimental data, theoretical MVL-ED50 thresholds for annular beam exposures were calculated using the Thompson-Gerstman granular model of laser-induced thermal damage to the retina. Threshold calculations were performed for the three experimental beam diameters and for an intermediate case with an outer beam diameter of 230 μm. Results indicate that the threshold vs. spot size trends, for annular beams, are similar to the trends for top hat beams determined in a previous study; i.e., the threshold dose varies with the retinal image area for larger image sizes. The model correctly predicts the threshold vs. spot size trends seen in the biological data, for both annular and top hat retinal beam profiles.

Modern retinal laser therapy

PubMed Central

Kozak, Igor; Luttrull, Jeffrey K.

2014-01-01

Medicinal lasers are a standard source of light to produce retinal tissue photocoagulation to treat retinovascular disease. The Diabetic Retinopathy Study and the Early Treatment Diabetic Retinopathy Study were large randomized clinical trials that have shown beneficial effect of retinal laser photocoagulation in diabetic retinopathy and have dictated the standard of care for decades. However, current treatment protocols undergo modifications. Types of lasers used in treatment of retinal diseases include argon, diode, dye and multicolor lasers, micropulse lasers and lasers for photodynamic therapy. Delivery systems include contact lens slit-lamp laser delivery, indirect ophthalmocope based laser photocoagulation and camera based navigated retinal photocoagulation with retinal eye-tracking. Selective targeted photocoagulation could be a future alternative to panretinal photocoagulation. PMID:25892934

A multi-step system for screening and localization of hard exudates in retinal images

NASA Astrophysics Data System (ADS)

Bopardikar, Ajit S.; Bhola, Vishal; Raghavendra, B. S.; Narayanan, Rangavittal

2012-03-01

The number of people being affected by Diabetes mellitus worldwide is increasing at an alarming rate. Monitoring of the diabetic condition and its effects on the human body are therefore of great importance. Of particular interest is diabetic retinopathy (DR) which is a result of prolonged, unchecked diabetes and affects the visual system. DR is a leading cause of blindness throughout the world. At any point of time 25 - 44% of people with diabetes are afflicted by DR. Automation of the screening and monitoring process for DR is therefore essential for efficient utilization of healthcare resources and optimizing treatment of the affected individuals. Such automation would use retinal images and detect the presence of specific artifacts such as hard exudates, hemorrhages and soft exudates (that may appear in the image) to gauge the severity of DR. In this paper, we focus on the detection of hard exudates. We propose a two step system that consists of a screening step that classifies retinal images as normal or abnormal based on the presence of hard exudates and a detection stage that localizes these artifacts in an abnormal retinal image. The proposed screening step automatically detects the presence of hard exudates with a high sensitivity and positive predictive value (PPV ). The detection/localization step uses a k-means based clustering approach to localize hard exudates in the retinal image. Suitable feature vectors are chosen based on their ability to isolate hard exudates while minimizing false detections. The algorithm was tested on a benchmark dataset (DIARETDB1) and was seen to provide a superior performance compared to existing methods. The two-step process described in this paper can be embedded in a tele-ophthalmology system to aid with speedy detection and diagnosis of the severity of DR.

Submacular hemorrhage in neovascular age-related macular degeneration: A synthesis of the literature.

PubMed

Stanescu-Segall, Dinu; Balta, Florian; Jackson, Timothy L

2016-01-01

Large submacular hemorrhage, an uncommon manifestation of neovascular age-related macular degeneration, may also occur with idiopathic polypoidal choroidal vasculopathy. Submacular hemorrhage damages photoreceptors owing to iron toxicity, fibrin meshwork contraction, and reduced nutrient flux, with subsequent macular scarring. Clinical and experimental studies support prompt treatment, as tissue damage can occur within 24 hours. Without treatment the natural history is poor, with a mean final visual acuity (VA) of 20/1600. Reported treatments include retinal pigment epithelial patch, macular translocation, pneumatic displacement, intravitreal or subretinal tissue plasminogen activator, intravitreal anti-vascular endothelial growth factor (VEGF) drugs, and combinations thereof. In the absence of comparative studies, we combined eligible studies to assess the VA change before and after each treatment option. The greatest improvement occurred after combined pars plana vitrectomy, subretinal tissue plasminogen activator, intravitreal gas, and anti-vascular endothelial growth factor treatment, with VA improving from 20/1000 to 20/400. The best final VA occurred using combined intravitreal tissue plasminogen activator, gas, and anti-vascular endothelial growth factor therapy, with VA improving from 20/200 to 20/100. Both treatments had an acceptable safety profile, but most studies were small, and larger randomized controlled trials are needed to determine both safety and efficacy. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

Mitochondrial Dysfunction in Retinal Diseases

PubMed Central

Barot, Megha; Gokulgandhi, Mitan R.; Mitra, Ashim K.

2015-01-01

The mitochondrion is a vital intracellular organelle for retinal cell function and survival. There is growing confirmation to support an association between mitochondrial dysfunction and a number of retinal degenerations. Investigations have also unveiled mitochondrial genomic instability as one of the contributing factors for age-related retinal pathophysiology. This review highlights the role of mitochondrial dysfunction originating from oxidative stress in the etiology of retinal diseases including diabetic retinopathy, glaucoma and age-related macular degeneration (AMD). Moreover, mitochondrial DNA (mtDNA) damage associated with AMD due to susceptibility of mtDNA to oxidative damage and failure of mtDNA repair pathways is also highlighted in this review. The susceptibility of neural retina and retinal pigment epithelium (RPE) mitochondria to oxidative damage with ageing appears to be a major factor in retinal degeneration. It thus appears that the mitochondrion is a weak link in the antioxidant defenses of retinal cells. In addition, failure of mtDNA repair pathways can also specifically contribute towards pathogenesis of AMD. This review will further summarize the prospective role of mitochondria targeting therapeutic agents for the treatment of retinal disease. Mitochondria based drug targeting to diminish oxidative stress or promote repair of mtDNA damage may offer potential alternatives for the treatment of various retinal degenerative diseases. PMID:21978133

Mitochondrial dysfunction in retinal diseases.

PubMed

Barot, Megha; Gokulgandhi, Mitan R; Mitra, Ashim K

2011-12-01

The mitochondrion is a vital intracellular organelle for retinal cell function and survival. There is growing confirmation to support an association between mitochondrial dysfunction and a number of retinal degenerations. Investigations have also unveiled mitochondrial genomic instability as one of the contributing factors for age-related retinal pathophysiology. This review highlights the role of mitochondrial dysfunction originating from oxidative stress in the etiology of retinal diseases including diabetic retinopathy, glaucoma and age-related macular degeneration (AMD). Moreover, mitochondrial DNA (mtDNA) damage associated with AMD due to susceptibility of mtDNA to oxidative damage and failure of mtDNA repair pathways is also highlighted in this review. The susceptibility of neural retina and retinal pigment epithelium (RPE) mitochondria to oxidative damage with ageing appears to be a major factor in retinal degeneration. It thus appears that the mitochondrion is a weak link in the antioxidant defenses of retinal cells. In addition, failure of mtDNA repair pathways can also specifically contribute towards pathogenesis of AMD. This review will further summarize the prospective role of mitochondria targeting therapeutic agents for the treatment of retinal disease. Mitochondria based drug targeting to diminish oxidative stress or promote repair of mtDNA damage may offer potential alternatives for the treatment of various retinal degenerative diseases.

Probing how initial retinal configuration controls photochemical dynamics in retinal proteins

NASA Astrophysics Data System (ADS)

Wand, A.; Rozin, R.; Eliash, T.; Friedman, N.; Jung, K. H.; Sheves, M.; Ruhman, S.

2013-03-01

The effects of the initial retinal configuration and the active isomerization coordinate on the photochemistry of retinal proteins (RPs) are assessed by comparing photochemical dynamics of two stable retinal ground state configurations (all-trans,15-anti vs. 13-cis,15-syn), within two RPs: Bacteriorhodopsin (BR) and Anabaena Sensory Rhodopsin (ASR). Hyperspectral pump-probe spectroscopy shows that photochemistry starting from 13-cis retinal in both proteins is 3-10 times faster than when started in the all-trans state, suggesting that the hastening is ubiquitous to microbial RPs, regardless of their different biological functions and origin. This may also relate to the known disparity of photochemical rates between microbial RPs and visual pigments. Importance and possible underlying mechanisms are discussed as well.

Intracellular Signalling in Retinal Ischemia

DTIC Science & Technology

1990-07-01

36) However, vascularization of the RPE is not known to occur in human diseases of photoreceptor degeneration, such as retinitis pigmentosa ...A.C. (1986) Retinitis pigmentosa and retinal neovascularization. Ophthalmology 91, 1599- 1603. Figure la: Control rat retina, 8 weeks of age, central...TITLE (Include Security Classification) Intracellular Signalling in Retinal Ischemia 12. PERSONAL AUTHOR(S) Burns, Margaret Sue; Bellhorn, Roy William

Bilateral rhegmatogenous retinal detachment due to unusual retinal degeneration in Down syndrome: A case report.

PubMed

Yonemoto, Yumiko; Morishita, Seita; Fukumoto, Masanori; Mimura, Masashi; Sato, Takaki; Kida, Teruyo; Kojima, Shota; Oku, Hidehiro; Sugasawa, Jun; Ikeda, Tsunehiko

2018-06-01

The aim of this study was to report a case of Down syndrome (DS) complicated with bilateral retinal detachment (RD) due to unusual retinal degeneration. A 9-year-old girl complained of bilateral visual disturbance during a follow-up examination for myopia and strabismus. Slit-lamp examination revealed moderate posterior subcapsular cataract in both eyes. B-mode echography showed bilateral bullous RD; however, it was difficult to detect the causal retinal breaks due to poor mydriasis. For treatment, the patient underwent bilateral lensectomy, vitrectomy, and silicone oil tamponade. Intraoperative findings revealed symmetrical retinal breaks and unusual caterpillar-like retinal degeneration on the upper temporal side of both eyes. Three months later, the patient underwent bilateral silicone oil removal and intraocular lens implantation. In this case, the retinal degeneration was morphologically different from retinal lattice degeneration, thus suggesting that it might be involved in the onset of DS-related bilateral RD.

Blood-filled cerebrospinal fluid-enhanced pericyte microvasculature contraction in rat retina: A novel in vitro study of subarachnoid hemorrhage

PubMed Central

Liu, Zhi; Li, Qiang; Cui, Gaoyu; Zhu, Gang; Tang, Weihua; Zhao, Hengli; Zhang, John H.; Chen, Yujie; Feng, Hua

2016-01-01

Previously, it was widely accepted that the delayed ischemic injury and poor clinical outcome following subarachnoid hemorrhage (SAH) was caused by cerebral vasospasm. This classical theory was challenged by a clazosentan clinical trial, which failed to improve patient outcome, despite reversing angiographic vasospasm. One possible explanation for the results of this trial is the changes in microcirculation following SAH, particularly in pericytes, which are the primary cell type controlling microcirculation in the brain parenchyma. However, as a result of technical limitations and the lack of suitable models, there was no direct evidence of microvessel dysfunction following SAH. In the present study, whole-mount retinal microvasculature has been introduced to study microcirculation in the brain following experimental SAH in vitro. Artificial blood-filled cerebrospinal fluid (BSCF) was applied to the retinal microvasculature to test the hypothesis that the presence of subarachnoid blood affects the contractile properties of the pericytes containing cerebral microcirculation during the early phase of SAH. It was observed that BCSF induced retina microvessel contraction and that this contraction could be resolved by BCSF wash-out. Furthermore, BCSF application accelerated pericyte-populated collagen gel contraction and increased the expression of α-smooth muscle actin. In addition, BCSF induced an influx of calcium in cultured retinal pericytes. In conclusion, the present study demonstrates increased contractility of retinal microvessels and pericytes in the presence of BCSF in vitro. These findings suggest that pericyte contraction and microvascular dysfunction is induced following SAH, which could lead to greater susceptibility to SAH-induced ischemia. PMID:27698742

Perioperative spontaneous bilateral suprachoroidal hemorrhage

PubMed Central

Haridas, Anjana; Litwin, Andre S.; Coker, Timothy

2011-01-01

Summary Suprachoroidal hemorrhage is a rare condition, occurring most commonly in the perioperative period, although cases of unilateral spontaneous hemorrhages have been reported. We report a case of bilateral spontaneous suprachoroidal hemorrhage and discuss the potential causative factors. PMID:23362387

Fundus autofluorescence and retinal structure as determined by spectral domain optical coherence tomography, and retinal function in retinitis pigmentosa.

PubMed

Iriyama, Aya; Yanagi, Yasuo

2012-03-01

To investigate the association between fundus autofluorescence (FAF) and retinal structure and function in retinitis pigmentosa (RP). For image acquisition, HRA2 (Heidelberg Engineering) and 3D-OCT1000 (Topcon Corp.) were used. Based on FAF examination, 88 eyes of 44 RP patients were categorized into three types. The area within the hyperautofluorescent ring and the area of preserved retinal autofluorescence with FAF was calculated. The association between the pattern of FAF and the residual area of the junction between the inner and outer segments of the photoreceptors (IS/OS line), and the relationship between the area within hyperautofluorescent ring, the area of preserved retinal autofluorescence and the mean deviation (MD) of static perimetry were assessed. Twenty-four eyes were with preserved retinal autofluorescence without hyperautofluorescent ring, 54 eyes were with hyperautofluorescent ring and ten eyes were with abnormal foveal autofluorescence both in the fovea and the periphery of the 30° scan. In the first type, the IS/OS line was clearly detected. In the second type, the residual area of the partially distinct IS/OS line corresponded with the area within hyperautofluorescent ring with significant correlation between the area within hyperautofluorescent ring and the MD (R(2) = 0.705, p < 0.001); however, there was no correlation between the area of preserved retinal autofluorescence and the MD, or between the area of preserved retinal autofluorescence and the area within hyperautofluorescent ring. In the third type, the IS/OS line was completely absent. The residual IS/OS line can be found in the area inside the hyperautofluorescent ring and correlates with residual visual function.

Retinal Prosthesis System for Advanced Retinitis Pigmentosa: A Health Technology Assessment

PubMed Central

Lee, Christine; Tu, Hong Anh; Weir, Mark; Holubowich, Corinne

2016-01-01

Background Retinitis pigmentosa is a group of genetic disorders that involves the breakdown and loss of photoreceptors in the retina, resulting in progressive retinal degeneration and eventual blindness. The Argus II Retinal Prosthesis System is the only currently available surgical implantable device approved by Health Canada. It has been shown to improve visual function in patients with severe visual loss from advanced retinitis pigmentosa. The objective of this analysis was to examine the clinical effectiveness, cost-effectiveness, budget impact, and safety of the Argus II system in improving visual function, as well as exploring patient experiences with the system. Methods We performed a systematic search of the literature for studies examining the effects of the Argus II retinal prosthesis system in patients with advanced retinitis pigmentosa, and appraised the evidence according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria, focusing on visual function, functional outcomes, quality of life, and adverse events. We developed a Markov decision-analytic model to assess the cost-effectiveness of the Argus II system compared with standard care over a 10-year time horizon. We also conducted a 5-year budget impact analysis. We used a qualitative design and an interview methodology to examine patients’ lived experience, and we used a modified grounded theory methodology to analyze information from interviews. Transcripts were coded, and themes were compared against one another. Results One multicentre international study and one single-centre study were included in the clinical review. In both studies, patients showed improved visual function with the Argus II system. However, the sight-threatening surgical complication rate was substantial. In the base-case analysis, the Argus II system was cost-effective compared with standard care only if willingness-to-pay was more than $207,616 per quality-adjusted life

Retinal Prosthesis System for Advanced Retinitis Pigmentosa: A Health Technology Assessment.

PubMed

2016-01-01

Retinitis pigmentosa is a group of genetic disorders that involves the breakdown and loss of photoreceptors in the retina, resulting in progressive retinal degeneration and eventual blindness. The Argus II Retinal Prosthesis System is the only currently available surgical implantable device approved by Health Canada. It has been shown to improve visual function in patients with severe visual loss from advanced retinitis pigmentosa. The objective of this analysis was to examine the clinical effectiveness, cost-effectiveness, budget impact, and safety of the Argus II system in improving visual function, as well as exploring patient experiences with the system. We performed a systematic search of the literature for studies examining the effects of the Argus II retinal prosthesis system in patients with advanced retinitis pigmentosa, and appraised the evidence according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria, focusing on visual function, functional outcomes, quality of life, and adverse events. We developed a Markov decision-analytic model to assess the cost-effectiveness of the Argus II system compared with standard care over a 10-year time horizon. We also conducted a 5-year budget impact analysis. We used a qualitative design and an interview methodology to examine patients' lived experience, and we used a modified grounded theory methodology to analyze information from interviews. Transcripts were coded, and themes were compared against one another. One multicentre international study and one single-centre study were included in the clinical review. In both studies, patients showed improved visual function with the Argus II system. However, the sight-threatening surgical complication rate was substantial. In the base-case analysis, the Argus II system was cost-effective compared with standard care only if willingness-to-pay was more than $207,616 per quality-adjusted life-year. The 5-year budget

Peripheral Retinal Vascular Patterns in Patients with Rhegmatogenous Retinal Detachment in Taiwan

PubMed Central

Chen, San-Ni; Hwang, Jiunn-Feng; Wu, Wen-Chuan

2016-01-01

This is an observational study of fluorescein angiography (FA) in consecutive patients with rhegmatogenous retinal detachment (RRD) in Changhua Christian Hospital to investigate the peripheral retinal vascular patterns in those patients. All patients had their age, sex, axial length (AXL), and refraction status (RF) recorded. According to the findings in FA of the peripheral retina, the eyes were divided into 4 groups: in group 1, there was a ramified pattern of peripheral retinal vasculature with gradual tapering; in group 2, there was an abrupt ending of peripheral vasculature with peripheral non-perfusion; in group 3, there was a curving route of peripheral vasculature forming vascular arcades or anastomosis; and in group 4, the same as in group 3, but with one or more wedge-shaped avascular notches. Comparisons of age, sex, AXL, and RF, association of breaks with lattice degeneration and retinal non-perfusion, surgical procedures utilized, and mean numbers of operations were made among the four groups. Of the 73 eyes studied, there were 13 eyes (17.8%) in group 1, 3 eyes (4.1%) in group 2, 40 eyes (54.8%) in group 3 and 17 eyes (23.3%) in group 4. Significant differences in age, AXL and RF, and association of retinal breaks to non-perfusion were noted among the four groups. Patients in group 1 had older ages, while younger ages were noted in groups 3 and 4. Eyes in group 1 had the shortest average AXL and were least myopic in contrast to the eyes in groups 3 and 4. Association of retinal breaks and retinal non-perfusion was significantly higher in groups 2, 3 and 4 than in group 1. In conclusion, peripheral vascular anomalies are common in cases with RRD. Patients with peripheral non-perfusion tend to be younger, with longer axial length and have the breaks associated with retinal non-perfusion. PMID:26909812

Genetics Home Reference: retinitis pigmentosa

MedlinePlus

... Email Facebook Twitter Home Health Conditions Retinitis pigmentosa Retinitis pigmentosa Printable PDF Open All Close All Enable Javascript to view the expand/collapse boxes. Description Retinitis pigmentosa is a group of related eye disorders that ...

Repair of Traumatic Rhegmatogenous Retinal Detachment Combined with Congenital Falciform Retinal Detachment.

PubMed

Mano, Fukutaro; Chang, Kuo-Chung; Mano, Tomiya

2018-01-01

To report a case of surgical repair of traumatic rhegmatogenous retinal detachment combined with congenital falciform retinal detachment (FRD). A retrospective case report. A 36-year-old man with traumatic rhegmatogenous retinal detachment complicating a previously known FRD was successfully treated despite residual FRD following pars plana lensectomy, vitrectomy, and encircling scleral buckling. His best corrected visual acuity improved from hand motion at 50 cm to 20/1,000. We concluded that the root of the FRD is susceptible to trauma because of the contraction of fibrovascular tissue. The early intervention of modern vitrectomy to traumatic rhegmatogenous retinal detachment complicating a previously known FRD is an important consideration for enhanced quality of care and optimal patient outcomes.

ADULT WITH CHICKENPOX COMPLICATED BY SYSTEMIC VASCULITIS AND BILATERAL RETINAL VASCULITIS WITH RETINAL VASCULAR OCCLUSIONS.

PubMed

Murdock, Jennifer; Carvounis, Petros E

2017-01-01

To describe an adult with chickenpox resulting in systemic vasculitis and bilateral retinal vascular occlusions. Single case report. A 58-year-old man with chickenpox complicated by disseminated varicella-zoster systemic and retinal vasculitis resulting in a combined arterial and venous occlusion in one eye with multiple branch retinal vein occlusions in the other eye. There was no evidence of retinitis. The patient systemically improved after treatment with acyclovir and steroids; however, his vision remained poor. Chickenpox can be associated with systemic vasculopathy and may rarely result in multiple systemic and ocular infarcts, including severe retinal vascular occlusions.

Investigation of Retinal Morphology Alterations Using Spectral Domain Optical Coherence Tomography in a Mouse Model of Retinal Branch and Central Retinal Vein Occlusion

PubMed Central

Ebneter, Andreas; Agca, Cavit; Dysli, Chantal; Zinkernagel, Martin S.

2015-01-01

Retinal vein occlusion is a leading cause of visual impairment. Experimental models of this condition based on laser photocoagulation of retinal veins have been described and extensively exploited in mammals and larger rodents such as the rat. However, few reports exist on the use of this paradigm in the mouse. The objective of this study was to investigate a model of branch and central retinal vein occlusion in the mouse and characterize in vivo longitudinal retinal morphology alterations using spectral domain optical coherence tomography. Retinal veins were experimentally occluded using laser photocoagulation after intravenous application of Rose Bengal, a photo-activator dye enhancing thrombus formation. Depending on the number of veins occluded, variable amounts of capillary dropout were seen on fluorescein angiography. Vascular endothelial growth factor levels were markedly elevated early and peaked at day one. Retinal thickness measurements with spectral domain optical coherence tomography showed significant swelling (p<0.001) compared to baseline, followed by gradual thinning plateauing two weeks after the experimental intervention (p<0.001). Histological findings at day seven correlated with spectral domain optical coherence tomography imaging. The inner layers were predominantly affected by degeneration with the outer nuclear layer and the photoreceptor outer segments largely preserved. The application of this retinal vein occlusion model in the mouse carries several advantages over its use in other larger species, such as access to a vast range of genetically modified animals. Retinal changes after experimental retinal vein occlusion in this mouse model can be non-invasively quantified by spectral domain optical coherence tomography, and may be used to monitor effects of potential therapeutic interventions. PMID:25775456

Frequency and determinants for hemorrhagic transformation of posterior cerebral stroke : Posterior ischemic stroke and hemorrhagic transformation.

PubMed

Valentino, Francesca; Gentile, Luana; Terruso, Valeria; Mastrilli, Sergio; Aridon, Paolo; Ragonese, Paolo; Sarno, Caterina; Savettieri, Giovanni; D'Amelio, Marco

2017-11-13

hemorrhagic transformation is a threatening ischemic stroke complication. Frequency of hemorrhagic transformation differs greatly among studies, and its risk factors have been usually studied in patients with anterior ischemic stroke who received thrombolytic therapy. We evaluated, in a hospital-based series of patients with posterior ischemic stroke not treated with thrombolysis, frequency and risk factors of hemorrhagic transformation. Patients with posterior circulation stroke were seen in our Department during the period January 2004 to December 2009. Demographic and clinical information were collected. We estimated risk for spontaneous hemorrhagic transformation by means of uni- and multivariate logistic regression analyses. 119 consecutive patients were included (73 males, 61.3%). Hemorrhagic transformation was observed in 7 patients (5.9%). Only clinical worsening was significantly associated with hemorrhagic transformation (OR 6.8, 95% CI 1.3-34.5). Our findings indicate that patients with posterior have a low risk of spontaneous hemorrhagic transformation, suggesting that these patients might have greater advantage from intravenous thrombolysis.

[Cytomegalovirus retinitis in immunocompetent patients].

PubMed

Yoshinaga, Wakako; Mizushima, Yuka; Abematsu, Noriko; Nakao, Kumiko; Sakamoto, Taiji

2008-08-01

Cytomegalovirus (CMV) retinitis usually affects severely immunosuppressed individuals. We report two immunocompetent patients who developed CMV retinitis. Case 1 was a 65-year-old man who was referred to us with blurred vision and floaters of 2 weeks duration in his left eye. Slit-lamp biomicroscopy showed keratic precipitates, aqueous cells, and vitreous opacity in his left eye. Funduscopic examination revealed yellow-white retinal lesions with arterial sheathing in the superotemporal midperiphery. Case 2 was a 63-year-old man who presented with a 2-week history of blurred vision in his left eye. Ophthalmologic examination of the left eye showed keratic precipitates, aqueous cells, vitreous opacity, and yellow-white lesions in the superotemporal peripheral retina. In both cases, CMV DNA was detected in the aqueous humor and therefore the diagnosis was CMV retinitis. CMV retinitis in both cases was indolent and was resolved in one month without treatment with antiviral drugs. Although both patients had diabetes mellitus, the results of their laboratory examinations were unremarkable and they were immunocompetent. Unlike CMV retinitis in immunocompromised patients, CMV retinitis in immunocompetent patients had significant anterior and vitreous inflammation but did not require antiviral treatment. A possible association between CMV retinitis and diabetes mellitus was suggested.

Retinal imaging and image analysis.

PubMed

Abràmoff, Michael D; Garvin, Mona K; Sonka, Milan

2010-01-01

Many important eye diseases as well as systemic diseases manifest themselves in the retina. While a number of other anatomical structures contribute to the process of vision, this review focuses on retinal imaging and image analysis. Following a brief overview of the most prevalent causes of blindness in the industrialized world that includes age-related macular degeneration, diabetic retinopathy, and glaucoma, the review is devoted to retinal imaging and image analysis methods and their clinical implications. Methods for 2-D fundus imaging and techniques for 3-D optical coherence tomography (OCT) imaging are reviewed. Special attention is given to quantitative techniques for analysis of fundus photographs with a focus on clinically relevant assessment of retinal vasculature, identification of retinal lesions, assessment of optic nerve head (ONH) shape, building retinal atlases, and to automated methods for population screening for retinal diseases. A separate section is devoted to 3-D analysis of OCT images, describing methods for segmentation and analysis of retinal layers, retinal vasculature, and 2-D/3-D detection of symptomatic exudate-associated derangements, as well as to OCT-based analysis of ONH morphology and shape. Throughout the paper, aspects of image acquisition, image analysis, and clinical relevance are treated together considering their mutually interlinked relationships.

Retinal Imaging and Image Analysis

PubMed Central

Abràmoff, Michael D.; Garvin, Mona K.; Sonka, Milan

2011-01-01

Many important eye diseases as well as systemic diseases manifest themselves in the retina. While a number of other anatomical structures contribute to the process of vision, this review focuses on retinal imaging and image analysis. Following a brief overview of the most prevalent causes of blindness in the industrialized world that includes age-related macular degeneration, diabetic retinopathy, and glaucoma, the review is devoted to retinal imaging and image analysis methods and their clinical implications. Methods for 2-D fundus imaging and techniques for 3-D optical coherence tomography (OCT) imaging are reviewed. Special attention is given to quantitative techniques for analysis of fundus photographs with a focus on clinically relevant assessment of retinal vasculature, identification of retinal lesions, assessment of optic nerve head (ONH) shape, building retinal atlases, and to automated methods for population screening for retinal diseases. A separate section is devoted to 3-D analysis of OCT images, describing methods for segmentation and analysis of retinal layers, retinal vasculature, and 2-D/3-D detection of symptomatic exudate-associated derangements, as well as to OCT-based analysis of ONH morphology and shape. Throughout the paper, aspects of image acquisition, image analysis, and clinical relevance are treated together considering their mutually interlinked relationships. PMID:22275207

Imaging of Hemorrhagic Stroke.

PubMed

Hakimi, Ryan; Garg, Ankur

2016-10-01

Hemorrhagic stroke comprises approximately 15% to 20% of all strokes. This article provides readers with an understanding of the indications and significance of various neuroimaging techniques available for patients presenting with hemorrhagic strokes of distinct causes. The most common initial neuroimaging study is a noncontrast head CT, which allows for the identification of hemorrhage. Once an intracranial hemorrhage has been identified, the pattern of blood and the patient's medical history, neurologic examination, and laboratory studies lead the practitioner to pursue further neuroimaging studies to guide the medical, surgical, and interventional management. Given that hemorrhagic stroke constitutes a heterogeneous collection of diagnoses, the subsequent neuroimaging pathway necessary to better evaluate and care for these patients is variable based on the etiology.With an increasing incidence and prevalence of atrial fibrillation associated with the aging population and the introduction of three new direct factor Xa inhibitors and one direct thrombin inhibitor to complement vitamin K antagonists, oral anticoagulant use continues to increase. Patients on oral anticoagulants have a sevenfold to tenfold increased risk for intracerebral hemorrhage (ICH). Furthermore, patients who have an ICH associated with oral anticoagulant use have a higher mortality rate than those with primary ICH. Despite the reduced incidence of hypertension-related ICH over the past decade, it is expected that the incidence of ICH will continue to increase. Neuroimaging studies are integral to the identification of hemorrhagic stroke, determination of the underlying etiology, prevention of hematoma expansion, treatment of acute complications, and treatment of the underlying etiology, if indicated. Neuroimaging is essential for prognostication and thus directly impacts patient care.

Repair of Traumatic Rhegmatogenous Retinal Detachment Combined with Congenital Falciform Retinal Detachment

PubMed Central

Mano, Fukutaro; Chang, Kuo-Chung; Mano, Tomiya

2018-01-01

Purpose To report a case of surgical repair of traumatic rhegmatogenous retinal detachment combined with congenital falciform retinal detachment (FRD). Methods A retrospective case report. Results A 36-year-old man with traumatic rhegmatogenous retinal detachment complicating a previously known FRD was successfully treated despite residual FRD following pars plana lensectomy, vitrectomy, and encircling scleral buckling. His best corrected visual acuity improved from hand motion at 50 cm to 20/1,000. Conclusion We concluded that the root of the FRD is susceptible to trauma because of the contraction of fibrovascular tissue. The early intervention of modern vitrectomy to traumatic rhegmatogenous retinal detachment complicating a previously known FRD is an important consideration for enhanced quality of care and optimal patient outcomes. PMID:29643782

Color Doppler imaging of retinal diseases.

PubMed

Dimitrova, Galina; Kato, Satoshi

2010-01-01

Color Doppler imaging (CDI) is a widely used method for evaluating ocular circulation that has been used in a number of studies on retinal diseases. CDI assesses blood velocity parameters by using ultrasound waves. In ophthalmology, these assessments are mainly performed on the retrobulbar blood vessels: the ophthalmic, the central retinal, and the short posterior ciliary arteries. In this review, we discuss CDI use for the assessment of retinal diseases classified into the following: vascular diseases, degenerations, dystrophies, and detachment. The retinal vascular diseases that have been investigated by CDI include diabetic retinopathy, retinal vein occlusions, retinal artery occlusions, ocular ischemic conditions, and retinopathy of prematurity. Degenerations and dystrophies included in this review are age-related macular degeneration, myopia, and retinitis pigmentosa. CDI has been used for the differential diagnosis of retinal detachment, as well as the evaluation of retrobulbar circulation in this condition. CDI is valuable for research and is a potentially useful diagnostic tool in the clinical setting.

Panoramic autofluorescence: highlighting retinal pathology.

PubMed

Slotnick, Samantha; Sherman, Jerome

2012-05-01

Recent technological advances in fundus autofluorescence (FAF) are providing new opportunities for insight into retinal physiology and pathophysiology. FAF provides distinctly different imaging information than standard photography or color separation. A review of the basis for this imaging technology is included to help the clinician understand how to interpret FAF images. Cases are presented to illustrate image interpretation. Optos, which manufactures equipment for simultaneous panoramic imaging, has recently outfitted several units with AF capabilities. Six cases are presented in which panoramic autofluorescent (PAF) images highlight retinal pathology, using Optos' Ultra-Widefield technology. Supportive imaging technologies, such as Optomap® images and spectral domain optical coherence tomography (SD-OCT), are used to assist in the clinical interpretation of retinal pathology detected on PAF. Hypofluorescent regions on FAF are identified to occur along with a disruption in the photoreceptors and/or retinal pigment epithelium, as borne out on SD-OCT. Hyperfluorescent regions on FAF occur at the advancing zones of retinal degeneration, indicating impending damage. PAF enables such inferences to be made in retinal areas which lie beyond the reach of SD-OCT imaging. PAF also enhances clinical pattern recognition over a large area and in comparison with the fellow eye. Symmetric retinal degenerations often occur with genetic conditions, such as retinitis pigmentosa, and may impel the clinician to recommend genetic testing. Autofluorescent ophthalmoscopy is a non-invasive procedure that can detect changes in metabolic activity at the retinal pigment epithelium before clinical ophthalmoscopy. Already, AF is being used as an adjunct technology to fluorescein angiography in cases of age-related macular degeneration. Both hyper- and hypoautofluorescent changes are indicative of pathology. Peripheral retinal abnormalities may precede central retinal impacts, potentially

WIDEFIELD SPECTRAL-DOMAIN OPTICAL COHERENCE TOMOGRAPHY IMAGING OF PERIPHERAL ROUND RETINAL HOLES WITH OR WITHOUT RETINAL DETACHMENT.

PubMed

Casswell, Edward J; Abou Ltaif, Sleiman; Carr, Thomas; Keane, Pearse A; Charteris, David G; Wickham, Louisa

2018-03-02

To describe the widefield spectral-domain optical coherence tomography features of peripheral round retinal holes, with or without associated retinal detachment (RD). Retrospective, observational study of 28 eyes with peripheral round retinal holes, with and without RD. Patients underwent imaging with a widefield 50-degree spectral-domain optical coherence tomography (Heidelberg Engineering, Germany) and Optos ultra-widefield imaging systems (Optos, United Kingdom). Vitreous attachment at the site of the retinal hole was detected in 27/28 (96.4%) cases. Cases were split into three groups: RHs with RD (n = 12); RHs with subretinal fluid (n = 5), and flat RHs (n = 11), with minimal or no subretinal fluid. 91.6% retinal holes associated with subretinal fluid or RD had vitreous attachment at the site of the hole. Eighty percent had vitreous attachment at both edges of the retinal hole, in a U-shape configuration, which appeared to exert traction. By contrast, flat retinal holes had visible vitreous attachment only at one edge of the retinal hole in 45.4%. Vitreous attachment was commonly seen at the site of round retinal holes. Vitreous attachment at both edges of the retinal hole in a U-shape configuration was more commonly seen at holes associated with subretinal fluid or RD.

Anosmia after perimesencephalic nonaneurysmal hemorrhage.

PubMed

Greebe, Paut; Rinkel, Gabriël J E; Algra, Ale

2009-08-01

Anosmia frequently occurs after aneurysmal subarachnoid hemorrhage not only after clipping, but also after endovascular coiling. Thus, at least in part, anosmia is caused by the hemorrhage itself and not only by surgical treatment. However, it is unknown whether anosmia is related to rupture of the aneurysm with sudden increase in intracranial pressure or to the presence of blood in the basal cisterns. Therefore, we studied the prevalence of anosmia in patients with nonaneurysmal perimesencephalic hemorrhage. We included all patients admitted to our hospital with perimesencephalic hemorrhage between 1983 and 2005. Patients were interviewed with a structured questionnaire. We calculated the proportion of patients with anosmia with corresponding 95% CIs. Nine of 148 patients (6.1%; 95% CI, 2.8% to 11%) had noticed anosmia shortly after the perimesencephalic hemorrhage. In 2, the anosmia had disappeared after 8 to12 weeks; in the other 7, it still persisted after a mean period of follow-up of 9 years. Anosmia occurs in one of every 16 patients with perimesencephalic hemorrhage, which is lower than previously reported rates after coiling in patients with subarachnoid hemorrhage but higher than rates after coiling for unruptured aneurysms. These data suggest that blood in the vicinity of the olfactory nerves plays a role in the development of anosmia.

Retinal O-linked N-acetylglucosamine protein modifications: implications for postnatal retinal vascularization and the pathogenesis of diabetic retinopathy

PubMed Central

Sieg, Kelsey M.; Shallow, Keegan D.; Sorenson, Christine M.; Sheibani, Nader

2013-01-01

Purpose Hyperglycemia activates several metabolic pathways, including the hexosamine biosynthetic pathway. Uridine diphosphate N-acetylglucosamine (GlcNAc) is the product of the hexosamine biosynthetic pathway and the substrate for O-linked GlcNAc (O-GlcNAc) modification. This modification affects a wide range of proteins by altering their activity, cellular localization, and/or protein interactions. However, the role O-GlcNAcylation may play in normal postnatal retinal vascular development and in the ocular complications of diabetes, including diabetic retinopathy, requires further investigation. Methods The total levels of O-GlcNAc-modified proteins were evaluated by western blot analysis of lysates prepared from retinas obtained at different days during postnatal retinal vascularization and oxygen-induced ischemic retinopathy. Similar experiments were performed with retinal lysate prepared from diabetic Ins2Akita/+ mice with different durations of diabetes and retinal vascular cells cultured under various glucose conditions. The localization of O-GlcNAc-modified proteins in the retinal vasculature was confirmed by immunofluorescence staining. The impact of altered O-GlcNAcylation on the migration of retinal vascular cells was determined using scratch wound and transwell migration assays. Results We detected an increase in protein O-GlcNAcylation during mouse postnatal retinal vascularization and aging, in part through the regulation of the enzymes that control this modification. The study of the diabetic Ins2Akita/+ mouse retina showed an increase in the O-GlcNAc modification of retinal proteins. We also observed an increase in retinal O-GlcNAcylated protein levels during the neovascularization phase of oxygen-induced ischemic retinopathy. Our fluorescence microscopy data confirmed that the alterations in retinal O-GlcNAcylation are similarly represented in the retinal vasculature and in retinal pericytes and endothelial cells. Particularly, the migration of

Retinal detachment following endophthalmitis.

PubMed

Nelsen, P T; Marcus, D A; Bovino, J A

1985-08-01

Fifty-five consecutive patients with a clinical diagnosis of bacterial endophthalmitis were reviewed. All patients were treated with systemic, periocular, topical, and intravitreal antibiotics. In addition, 33 of the patients underwent a pars plana vitrectomy. Nine retinal detachments occurred within six months of initial diagnosis. The higher frequency of retinal detachment in the vitrectomy group (21%) as compared to those patients managed without vitrectomy (9%) may be explained by a combination of surgical complications and the increased severity of endophthalmitis in the vitrectomy group. The two patients who developed retinal detachment during vitrectomy surgery rapidly progressed to no light perception. Conversely, the repair of retinal detachments diagnosed postoperatively had a good prognosis.

Effect of pharmacologically induced retinal degeneration on retinal autofluorescence lifetimes in mice.

PubMed

Dysli, Chantal; Dysli, Muriel; Zinkernagel, Martin S; Enzmann, Volker

2016-12-01

Fluorescence lifetime imaging ophthalmoscopy (FLIO) was used to investigate retinal autofluorescence lifetimes in mouse models of pharmacologically induced retinal degeneration over time. Sodium iodate (NaIO 3 , 35 mg/kg intravenously) was used to induce retinal pigment epithelium (RPE) degeneration with subsequent loss of photoreceptors (PR) whereas N-methyl-N-nitrosourea (MNU, 45 mg/kg intraperitoneally) was employed for degeneration of the photoreceptor cell layer alone. All mice were measured at day 3, 7, 14, and 28 after the respective injection of NaIO 3 , MNU or NaCl (control). Fluorescence lifetime imaging was performed using a fluorescence lifetime imaging ophthalmoscope (Heidelberg Engineering, Heidelberg, Germany). Fluorescence was excited at 473 nm and fluorescence lifetimes were measured in a short and a long spectral channel (498-560 nm and 560-720 nm). Corresponding optical coherence tomography (OCT) images were consecutively acquired and histology was performed at the end of the experiments. Segmentation of OCT images and histology verified the cell type-specific degeneration process over time. Retinal autofluorescence lifetimes increased from day 3 to day 28 in mice after NaIO 3 treatment. Finally, at day 28, fluorescence lifetimes were prolonged by 8% in the short and 61% in the long spectral channel compared to control animals (p = 0.21 and p = 0.004, respectively). In mice after MNU treatment, the mean retinal autofluorescence lifetimes were already decreased at day 3 and retinal lifetimes were finally shortened by 27% in the short and 51% in the long spectral channel at day 28 (p = 0.0028). In conclusion, degeneration of the RPE with subsequent photoreceptor degeneration by NaIO 3 lead to longer mean fluorescence lifetimes of the retina compared to control mice, whereas during specific degeneration of the photoreceptor layer induced by MNU shorter lifetimes were measured. Therefore, short retinal fluorescence lifetimes may originate

Perfluorocarbon-perfused 23 gauge three-dimensional vitrectomy for complicated diabetic tractional retinal detachment

PubMed Central

Velez-Montoya, Raul; Guerrero-Naranjo, Jose Luis; Garcia-Aguirre, Gerardo; Morales-Cantón, Virgilio; Fromow-Guerra, Jans; Quiroz-Mercado, Hugo

2011-01-01

Background Perfluorocarbon liquid (PCL)-perfused vitrectomy has been shown in previous studies to be feasible, safe, and to have advantages in managing complicated cases of tractional retinal detachment. The present study had the objectives of describing the anatomical results and measuring surgical time and PCL consumption when combining PCL-perfused techniques with modern vitrectomy equipment. Methods A prospective, interventional consecutive case series was investigated. We enrolled patients with diabetic tractional retinal detachment, complicated by proliferative vitreoretinopathy and poor vision. A 23 gauge PCL-perfused vitrectomy was done with three-dimensional settings. During the procedure, we assessed the degree of surgical bleeding, visualization quality, and difficulty of membrane dissections. Visual acuity, intraocular pressure, and anatomical success were assessed at one and 3 months of follow-up. Results Twelve patients were enrolled in this study. There were no statistical significant changes in intraocular pressure and visual acuity throughout the follow-up period. Surgery was performed in a hemorrhage-free environment in almost all cases, with good visualization and low technical difficulty. The mean complete surgical time was 94.92 ± 25.03 minutes. The mean effective vitrectomy time was 22.50 ± 19.04 minutes and the mean PCL consumption was 25.08 ± 9.76 mL, with a speed of 1.11 mL/minute. Anatomical success was 67% at 3 months. Conclusion Although the technique proved to have some advantages in managing complicated cases of diabetic tractional retinal detachment, there was a high consumption of PCL. A redesign of the entire system is needed in order to decrease the amount of PCL needed for the technique. PMID:22267907

Retinal patching: a new approach to the management of selected retinal breaks.

PubMed

Gilbert, C E; Grierson, I; McLeod, D

1989-01-01

Restoration of retinal continuity by a patching technique is proposed as a new means of treating selected rhegmatogenous retinal detachments where established techniques frequently fail. The patch consists of a substrate and adhesive applied to the inner surface of the retina surrounding the retinal break. Bovine eye cup experiments have been performed to explore the effectiveness of a range of adhesives, and cyanoacrylates and Tisseel have been found to be effective. Studies of these adhesives on confluent cultures of bovine retinal pigment epithelial cells and glia revealed temporary cyanoacrylate toxicity and stimulation of proliferation by Tisseel. Substrate biocompatability was investigated by observing the growth of cells on various substrates in tissue culture; biological substrates such as lens capsule supported cell growth whereas synthetic membranes only did so if pretreated with fibronectin.

A High Serum Iron Level Causes Mouse Retinal Iron Accumulation Despite an Intact Blood-Retinal Barrier

PubMed Central

Zhao, Liangliang; Li, Yafeng; Song, Delu; Song, Ying; Theurl, Milan; Wang, Chenguang; Cwanger, Alyssa; Su, Guanfang; Dunaief, Joshua L.

2015-01-01

The retina can be shielded by the blood-retinal barrier. Because photoreceptors are damaged by excess iron, it is important to understand whether the blood-retinal barrier protects against high serum iron levels. Bone morphogenic protein 6 (Bmp6) knockout mice have serum iron overload. Herein, we tested whether the previously documented retinal iron accumulation in Bmp6 knockout mice might result from the high serum iron levels or, alternatively, low levels of retinal hepcidin, an iron regulatory hormone whose transcription can be up-regulated by Bmp6. Furthermore, to determine whether increases in serum iron can elevate retinal iron levels, we i.v. injected iron into wild-type mice. Retinas were analyzed by real-time quantitative PCR and immunofluorescence to assess the levels of iron-regulated genes/proteins and oxidative stress. Retinal hepcidin mRNA levels in Bmp6 knockout retinas were the same as, or greater than, those in age-matched wild-type retinas, indicating that Bmp6 knockout does not cause retinal hepcidin deficiency. Changes in mRNA levels of L ferritin and transferrin receptor indicated increased retinal iron levels in i.v. iron-injected wild-type mice. Oxidative stress markers were elevated in photoreceptors of mice receiving i.v. iron. These findings suggest that elevated serum iron levels can overwhelm local retinal iron regulatory mechanisms. PMID:25174877

The Blood-Retinal Barrier in the Management of Retinal Disease: EURETINA Award Lecture.

PubMed

Cunha-Vaz, José

2017-01-01

Retinal diseases are the main causes of blindness in the Western world. Diabetic retinopathy and age-related macular degeneration continue to increase in prevalence and as main causes of vision loss. Intravitreal anti-VEGF and steroid injections have raised new expectations for their successful treatment. These agents act by stabilizing the blood-retinal barrier (BRB). Our group defined the BRB by identifying for the first time the tight junctions that unite retinal endothelial cells and are the basis for the inner BRB, an observation later confirmed in retinal pigment epithelial cells and in brain vessels. A major role of active transport processes was also identified. Today, the BRB is understood to play a fundamental role in retinal function in both health and disease. Retinal edema, an ubiquitous manifestation of retinal disease, is directly associated with breakdown of the BRB and with vision loss. In its most common form (i.e., vasogenic edema), due to breakdown of the BRB, Starling's law of capillary filtration may be used to interpret the mechanisms of fluid accumulation in the retina. The main factors involved in the development of retinal edema are BRB permeability, capillary hydrostatic pressure, tissue hydrostatic pressure, tissue osmotic pressure, and plasma osmotic pressure. In the clinical environment, breakdown of the BRB has been identified by fluorescein angiography and vitreous fluorometry, requiring the intravenous administration of fluorescein. An OCT-based method, OCT-Leakage, recently introduced by our group is capable of noninvasively identifying and quantifying sites of alteration of the BRB by mapping areas of lower-than-normal optical reflectivity, thus reflecting changes in the retinal extracellular fluid. We found good correspondence between the location of increased areas of low optical reflectivity identified by OCT-Leakage and the main sites of leakage on fluorescein angiography. Furthermore, with OCT-Leakage the areas of abnormal

Sector retinitis pigmentosa.

PubMed

Van Woerkom, Craig; Ferrucci, Steven

2005-05-01

Retinitis pigmentosa (RP) is one of the most common hereditary retinal dystrophies and causes of visual impairment affecting all age groups. The reported incidence varies, but is considered to be between 1 in 3,000 to 1 in 7,000. Sector retinitis pigmentosa is an atypical form of RP that is characterized by regionalized areas of bone spicule pigmentation, usually in the inferior quadrants of the retina. A 57-year-old Hispanic man with a history of previously diagnosed retinitis pigmentosa came to the clinic with a longstanding symptom of decreased vision at night. Bone spicule pigmentation was found in the nasal and inferior quadrants in each eye. He demonstrated superior and temporal visual-field loss corresponding to the areas of the affected retina. Clinical measurements of visual-field loss, best-corrected visual acuity, and ophthalmoscopic appearance have remained stable during the five years the patient has been followed. Sector retinitis pigmentosa is an atypical form of RP that is characterized by bilateral pigmentary retinopathy, usually isolated to the inferior quadrants. The remainder of the retina appears clinically normal, although studies have found functional abnormalities in these areas as well. Sector RP is generally considered a stationary to slowly progressive disease, with subnormal electro-retinogram findings and visual-field defects corresponding to the involved retinal sectors. Management of RP is very difficult because there are no proven methods of treatment. Studies have shown 15,000 IU of vitamin A palmitate per day may slow the progression, though this result is controversial. Low vision rehabilitation, long wavelength pass filters, and pedigree counseling remain the mainstay of management.

Characteristics of eyes with inner retinal cleavage.

PubMed

Hwang, Young Hoon; Kim, Yong Yeon; Kim, Hwang Ki; Sohn, Yong Ho

2015-02-01

Inner retinal cleavage can be misdiagnosed as a glaucomatous retinal nerve fiber layer (RNFL) defect. This study was performed to characterize eyes with inner retinal cleavage. Inner retinal cleavage is defined as the appearance of a dark spindle-shaped space between the nerve fibers. Patients who presented at our institution with inner retinal cleavage were enrolled in the study. All participants were evaluated by fundus examination, visual field testing with standard automated perimetry, and optical coherence tomography (OCT) imaging. A total of 15 eyes of 11 subjects with inner retinal cleavage were included in the study. The median age of the subjects was 57 years (age range, 30-67 years). In each case, inner retinal cleavage was located adjacent to retinal blood vessels. Tissue bridging the cleavage area was observed in ten eyes. Six eyes had epiretinal membranes (ERMs), two eyes had glaucoma, and one eye had ERM in addition to glaucoma. Six eyes with inner retinal cleavage without combined ocular abnormalities had highly myopic refractive error (-6.50 to -8.50 diopters). Cross-sectional OCT images of the areas of inner retinal cleavage demonstrated defects with irregular margins and empty spaces in the inner layers of the retina. During the follow-up period, no eye showed changes in inner retinal layer cleavage or visual field sensitivity. Inner retinal cleavage was found in eyes with high myopia or ERMs. Inner retinal cleavage was associated with structural changes distinct from those associated with glaucomatous RNFL defects.

Cone dysfunctions in retinitis pigmentosa with retinal nerve fiber layer thickening.

PubMed

Sobacı, Güngör; Ozge, Gökhan; Gündoğan, Fatih Ç

2012-01-01

To investigate whether or not thicker retinal nerve fiber layer (RNFL) in retinitis pigmentosa (RP) patients relates to functional abnormalities of the photoreceptors. Optical coherence tomography-based RNFL thickness was measured by Stratus-3™ (Zeiss, Basel, Switzerland) optical coherence tomography and electroretinogram (ERG) recordings made using the RETI-port(®) system (Roland, Wiesbaden, Germany) in 27 patients with retinitis pigmentosa and in 30 healthy subjects. Photopic ERG b-wave amplitude, cone ERG b-wave latency, 30 Hz flicker amplitude, and 30 Hz flicker latency had significant correlations to the RNFL-temporal (r = -0.55, P = 0.004, r = 0.68, P = 0.001, r = -0.65, P = 0.001, and r = -0.52, P = 0.007, respectively). Eyes with thicker RNFL (ten eyes) differed significantly from those with thinner RNFL (eight eyes) regarding cone ERG b-wave latency values only (P = 0.001). Thicker RNFL in patients with retinitis pigmentosa may be associated with functional abnormality of the cone system.

Progressive outer retinal necrosis (PORN) in AIDS patients: a different appearance of varicella-zoster retinitis.

PubMed

Pavesio, C E; Mitchell, S M; Barton, K; Schwartz, S D; Towler, H M; Lightman, S

1995-01-01

Retinal infections caused by the varicella-zoster virus (VZV) have been reported in immunocompetent and immunocompromised individuals. Two cases of a VZV-related retinitis are described with the characteristic features of the recently described progressive outer retinal necrosis (PORN) syndrome. Both patients suffered from the acquired immunodeficiency syndrome (AIDS) with greatly reduced peripheral blood CD4+ T lymphocyte counts, and presented with macular retinitis without vitritis. The disease was bilateral in one case and unilateral in the other. The clinical course was rapidly progressive with widespread retinal involvement and the development of rhegmatogenous retinal detachment with complete loss of vision in the affected eyes despite intensive intravenous antiviral therapy. VZV DNA was identified in vitreous biopsies, by molecular techniques based on the polymerase chain reaction (PCR), in both patients. At present, the use of very high-dose intravenous acyclovir may be the best therapeutic option in these patients for whom the visual prognosis is poor. Intravitreal antiviral drugs could also contribute to the management of these cases.

Retinal Oxygen: from animals to humans

PubMed Central

Linsenmeier, Robert A.; Zhang, Hao F.

2017-01-01

This article discusses retinal oxygenation and retinal metabolism by focusing on measurements made with two of the principal methods used to study O2 in the retina: measurements of PO2 with oxygen-sensitive microelectrodes in vivo in animals with a retinal circulation similar to that of humans, and oximetry, which can be used non-invasively in both animals and humans to measure O2 concentration in retinal vessels. Microelectrodes uniquely have high spatial resolution, allowing the mapping of PO2 in detail, and when combined with mathematical models of diffusion and consumption, they provide information about retinal metabolism. Mathematical models, grounded in experiments, can also be used to simulate situations that are not amenable to experimental study. New methods of oximetry, particularly photoacoustic ophthalmoscopy and visible light optical coherence tomography, provide depth-resolved methods that can separate signals from blood vessels and surrounding tissues, and can be combined with blood flow measures to determine metabolic rate. We discuss the effects on retinal oxygenation of illumination, hypoxia and hyperoxia, and describe retinal oxygenation in diabetes, retinal detachment, arterial occlusion, and macular degeneration. We explain how the metabolic measurements obtained from microelectrodes and imaging are different, and how they need to be brought together in the future. Finally, we argue for revisiting the clinical use of hyperoxia in ophthalmology, particularly in retinal arterial occlusions and retinal detachment, based on animal research and diffusion theory. PMID:28109737

Cytomegalovirus Retinitis: A Review.

PubMed

Port, Alexander D; Orlin, Anton; Kiss, Szilard; Patel, Sarju; D'Amico, Donald J; Gupta, Mrinali P

2017-05-01

Cytomegalovirus (CMV) is a ubiquitous DNA herpes virus that causes significant morbidity and mortality in immunocompromised individuals. CMV retinitis is a potentially blinding manifestation of CMV infection that was commonly seen in advanced acquired immunodeficiency syndrome (AIDS) in the era before modern combination antiretroviral therapy era, but is also recognized in patients with immune deficiency from multiple causes. The advent of and advances in antiretroviral therapies for human immunodeficiency virus have decreased the incidence of CMV retinitis by over 90% among AIDS patients, and improved visual outcomes in those affected. The diagnosis is generally a clinical one, and treatment modalities include systemic and intravitreal antiviral medications. Retinal detachment and immune recovery uveitis are sight-threatening complications of CMV retinitis that require specific treatments.

Retinal Remodeling in the Tg P347L Rabbit, a Large-Eye Model of Retinal Degeneration

PubMed Central

Jones, Bryan William; Kondo, Mineo; Terasaki, Hiroko; Watt, Carl Brock; Rapp, Kevin; Anderson, James; Lin, Yanhua; Shaw, Marguerite Victoria; Yang, Jia-Hui; Marc, Robert Edward

2013-01-01

Retinitis pigmentosa (RP) is an inherited blinding disease characterized by progressive loss of retinal photo-receptors. There are numerous rodent models of retinal degeneration, but most are poor platforms for interventions that will translate into clinical practice. The rabbit possesses a number of desirable qualities for a model of retinal disease including a large eye and an existing and substantial knowledge base in retinal circuitry, anatomy, and ophthalmology. We have analyzed degeneration, remodeling, and reprogramming in a rabbit model of retinal degeneration, expressing a rhodopsin proline 347 to leucine transgene in a TgP347L rabbit as a powerful model to study the pathophysiology and treatment of retinal degeneration. We show that disease progression in the TgP347L rabbit closely tracks human cone-sparing RP, including the cone-associated preservation of bipolar cell signaling and triggering of reprogramming. The relatively fast disease progression makes the TgP347L rabbit an excellent model for gene therapy, cell biological intervention, progenitor cell transplantation, surgical interventions, and bionic prosthetic studies. PMID:21681749

Placenta previa and maternal hemorrhagic morbidity.

PubMed

Gibbins, Karen J; Einerson, Brett D; Varner, Michael W; Silver, Robert M

2018-02-01

Placenta previa is associated with maternal hemorrhage, but most literature focuses on morbidity in the setting of placenta accreta. We aim to characterize maternal morbidity associated with previa and to define risk factors for hemorrhage. This is a secondary cohort analysis of the NICHD Maternal-Fetal Medicine Units Network Cesarean Section Registry. This analysis included all women undergoing primary Cesarean delivery without placenta accreta. About 496 women with previa were compared with 24,201 women without previa. Primary outcome was composite maternal hemorrhagic morbidity. Non-hemorrhagic morbidities and risk factors for hemorrhage were also evaluated. Maternal hemorrhagic morbidity was more common in women with previa (19 versus 7%, aRR 2.6, 95% CI 1.9-3.5). Atony requiring uterotonics (aRR 3.1, 95% CI 2.0-4.9), red blood cell transfusion (aRR 3.8, 95% CI 2.5-5.7), and hysterectomy (aRR 5.1, 95% CI 1.5-17.3) were also more common with previa. For women with previa, factors associated with maternal hemorrhage were pre-delivery anemia, thrombocytopenia, diabetes, magnesium use, and general anesthesia. Placenta previa is an independent risk factor for maternal hemorrhagic morbidity. Some risk factors are modifiable, but many are intrinsic to the clinical scenario.

Retinitis pigmentosa, Coats disease and uveitis.

PubMed

Solomon, A; Banin, E; Anteby, I; Benezra, D

1999-01-01

To study the anamnestic immune response to retinal specific antigens of two patients suffering from a rare triad of retinitis pigmentosa, Coats disease and uveitis. 17-year-old girl presented with an acute episode of panuveitis, and her 19-year-old brother suffered from chronic uveitis. On examination, both patients showed retinal vascular changes and subretinal exudations typical of Coats disease, with bone-spicule pigmentary changes as observed in retinitis pigmentosa. All routine examinations were unrevealing. However, the peripheral lymphocytes from these two siblings gave a specific anamnestic response to retinal antigens in vitro. A stimulation index of 4.6 was obtained when the sister's lymphocytes were stimulated with interphotoreceptor binding protein, IRBP--during the acute stage of the uveitis. The brother's lymphocytes showed a stimulation index of 2.7 towards S-Ag during the chronic phase of his uveitic condition. These results indicate that autoimmunity towards retinal antigens may play some role in specific types of retinitis pigmentosa. Whether these autoimmune reactions are a primary pathological mechanism or are secondary to the extensive destruction of the photoreceptor layer resulting from the retinitis pigmentosa remains debatable.

Retinal oxygen extraction in humans

NASA Astrophysics Data System (ADS)

Werkmeister, René M.; Schmidl, Doreen; Aschinger, Gerold; Doblhoff-Dier, Veronika; Palkovits, Stefan; Wirth, Magdalena; Garhöfer, Gerhard; Linsenmeier, Robert A.; Leitgeb, Rainer A.; Schmetterer, Leopold

2015-10-01

Adequate function of the retina is dependent on proper oxygen supply. In humans, the inner retina is oxygenated via the retinal circulation. We present a method to calculate total retinal oxygen extraction based on measurement of total retinal blood flow using dual-beam bidirectional Doppler optical coherence tomography and measurement of oxygen saturation by spectrophotometry. These measurements were done on 8 healthy subjects while breathing ambient room air and 100% oxygen. Total retinal blood flow was 44.3 ± 9.0 μl/min during baseline and decreased to 18.7 ± 4.2 μl/min during 100% oxygen breathing (P < 0.001) resulting in a pronounced decrease in retinal oxygen extraction from 2.33 ± 0.51 μl(O2)/min to 0.88 ± 0.14 μl(O2)/min during breathing of 100% oxygen. The method presented in this paper may have significant potential to study oxygen metabolism in hypoxic retinal diseases such as diabetic retinopathy.

Retinal oxygen extraction in humans

PubMed Central

Werkmeister, René M.; Schmidl, Doreen; Aschinger, Gerold; Doblhoff-Dier, Veronika; Palkovits, Stefan; Wirth, Magdalena; Garhöfer, Gerhard; Linsenmeier, Robert A.; Leitgeb, Rainer A.; Schmetterer, Leopold

2015-01-01

Adequate function of the retina is dependent on proper oxygen supply. In humans, the inner retina is oxygenated via the retinal circulation. We present a method to calculate total retinal oxygen extraction based on measurement of total retinal blood flow using dual-beam bidirectional Doppler optical coherence tomography and measurement of oxygen saturation by spectrophotometry. These measurements were done on 8 healthy subjects while breathing ambient room air and 100% oxygen. Total retinal blood flow was 44.3 ± 9.0 μl/min during baseline and decreased to 18.7 ± 4.2 μl/min during 100% oxygen breathing (P < 0.001) resulting in a pronounced decrease in retinal oxygen extraction from 2.33 ± 0.51 μl(O2)/min to 0.88 ± 0.14 μl(O2)/min during breathing of 100% oxygen. The method presented in this paper may have significant potential to study oxygen metabolism in hypoxic retinal diseases such as diabetic retinopathy. PMID:26503332

Measurement of retinal wall-to-lumen ratio by adaptive optics retinal camera: a clinical research.

PubMed

Meixner, Eva; Michelson, Georg

2015-11-01

To measure the wall-to-lumen ratio (WLR) and the cross-sectional area of the vascular wall (WCSA) of retinal arterioles by an Adaptive Optics (AO) retinal camera. Forty-seven human subjects were examined and their medical history was explored. WLR and WCSA were measured on the basis of retinal arteriolar wall thickness (VW), lumen diameter (LD) and vessel diameter (VD) assessed by rtx1 Adaptive Optics retinal camera. WLR was calculated by the formula [Formula: see text]. Arterio-venous ratio (AVR) and microvascular abnormalities were attained by quantitative and qualitative assessment of fundus photographs. Influence of age, arterial hypertension, body mass index (BMI) and retinal microvascular abnormalities on the WLR was examined. An age-adjusted WLR was created to test influences on WLR independently of age. Considering WLR and WCSA, a distinction between eutrophic and hypertrophic retinal remodeling processes was possible. The intra-observer variability (IOV) was 6 % ± 0.9 for arteriolar wall thickness and 2 % ± 0.2 for arteriolar wall thickness plus vessel lumen. WLR depended significantly on the wall thickness (r = 0.715; p < 0.01) of retinal arterioles, but was independent of the total vessel diameter (r = 0.052; p = 0.728). WLR correlated significantly with age (r = 0.769; p < 0.01). Arterial hypertension and a higher BMI were significantly associated with an increased age-adjusted WLR. WLR correlated significantly with the stage of microvascular abnormalities. 55 % of the hypertensive subjects and 11 % of the normotensive subjects showed eutrophic remodeling, while hypertrophic remodeling was not detectable. WLR correlated inversely with AVR. AVR was independent of the arteriolar wall thickness, age and arterial hypertension. The technique of AO retinal imaging allows a direct measurement of the retinal vessel wall and lumen diameter with good intra-observer variability. Age, arterial hypertension and an elevated BMI level

Retinal abnormalities in β-thalassemia major

PubMed Central

Bhoiwala, Devang L.; Dunaief, Joshua L.

2015-01-01

Patients with beta (β)-thalassemia (β-TM: thalassemia major, β-TI: thalassemia intermedia) have a variety of complications that may affect all organs, including the eye. Ocular abnormalities include retinal pigment epithelium degeneration, angioid streaks, venous tortuosity, night blindness, visual field defects, decreased visual acuity, color vision abnormalities, and acute visual loss. Patients with β-TM are transfusion dependent and require iron chelation therapy (ICT) in order to survive. Retinal degeneration may result from either retinal iron accumulation from transfusion-induced iron overload or retinal toxicity induced by ICT. Some who were never treated with ICT exhibited retinopathy, and others receiving ICT had chelator-induced retinopathy. We will focus on retinal abnormalities present in individuals with β-TM viewed in light of new findings on the mechanisms and manifestations of retinal iron toxicity. PMID:26325202

Evaluation of patient suitability for a retinal prosthesis using structural and functional tests of inner retinal integrity

NASA Astrophysics Data System (ADS)

Huang, Qiuhen; Chowdhury, Vivek; Coroneo, Minas Theodore

2009-06-01

The purpose of this study was to assess inner retinal structure and function in patients with retinitis pigmentosa (RP) using optical coherence tomography (OCT) imaging of the retina, and electrical stimulation of the retina with a contact lens electrode. OCT images of 17 RP patients were acquired at the macula and at four quadrants of the peripheral retina in both eyes. Analysis was made of the residual inner retinal thickness and nerve fibre layer thickness in RP patients, and this was compared to normal controls. Eight of these patients further underwent contact lens electrical stimulation of one eye and thresholds for phosphene perception were obtained. OCT imaging showed a significant amount of inner retinal preservation in the peripheral retina and the macula of RP patients despite severe visual acuity and visual field loss. Phosphene thresholds were obtained across the range of pulse durations tested but were much higher than those obtained in normal controls. Phosphene thresholds in RP patients moderately correlated with inner retinal thicknesses as measured by OCT. Preservation of inner retinal structure in patients with RP and the responsiveness of these eyes to electrical stimulation suggest adequate inner retinal preservation for a retinal prosthesis to be successful.

Enhanced generation of retinal progenitor cells from human retinal pigment epithelial cells induced by amniotic fluid.

PubMed

Sanie-Jahromi, Fatemeh; Ahmadieh, Hamid; Soheili, Zahra-Soheila; Davari, Maliheh; Ghaderi, Shima; Kanavi, Mozhgan Rezaei; Samiei, Shahram; Deezagi, Abdolkhalegh; Pakravesh, Jalil; Bagheri, Abouzar

2012-04-10

Retinal progenitor cells are a convenient source of cell replacement therapy in retinal degenerative disorders. The purpose of this study was to evaluate the expression patterns of the homeobox genes PAX6 and CHX10 (retinal progenitor markers) during treatment of human retinal pigment epithelium (RPE) cells with amniotic fluid (AF), RPE cells harvested from neonatal cadaver globes were cultured in a mixture of DMEM and Ham's F12 supplemented with 10% FBS. At different passages, cells were trypsinized and co-cultured with 30% AF obtained from normal fetuses of 1416 weeks gestational age. Compared to FBS-treated controls, AF-treated cultures exhibited special morphological changes in culture, including appearance of spheroid colonies, improved initial cell adhesion and ordered cell alignment. Cell proliferation assays indicated a remarkable increase in the proliferation rate of RPE cells cultivated in 30% AF-supplemented medium, compared with those grown in the absence of AF. Immunocytochemical analyses exhibited nuclear localization of retinal progenitor markers at a ratio of 33% and 27% for CHX10 and PAX6, respectively. This indicated a 3-fold increase in retinal progenitor markers in AF-treated cultures compared to FBS-treated controls. Real-time PCR data of retinal progenitor genes (PAX6, CHX10 and VSX-1) confirmed these results and demonstrated AF's capacity for promoting retinal progenitor cell generation. Taken together, the results suggest that AF significantly promotes the rate of retinal progenitor cell generation, indicating that AF can be used as an enriched supplement for serum-free media used for the in vitro propagation of human progenitor cells.

Inner retinal preservation in rat models of retinal degeneration implanted with subretinal photovoltaic arrays.

PubMed

Light, Jacob G; Fransen, James W; Adekunle, Adewumi N; Adkins, Alice; Pangeni, Gobinda; Loudin, James; Mathieson, Keith; Palanker, Daniel V; McCall, Maureen A; Pardue, Machelle T

2014-11-01

Photovoltaic arrays (PVA) implanted into the subretinal space of patients with retinitis pigmentosa (RP) are designed to electrically stimulate the remaining inner retinal circuitry in response to incident light, thereby recreating a visual signal when photoreceptor function declines or is lost. Preservation of inner retinal circuitry is critical to the fidelity of this transmitted signal to ganglion cells and beyond to higher visual targets. Post-implantation loss of retinal interneurons or excessive glial scarring could diminish and/or eliminate PVA-evoked signal transmission. As such, assessing the morphology of the inner retina in RP animal models with subretinal PVAs is an important step in defining biocompatibility and predicting success of signal transmission. In this study, we used immunohistochemical methods to qualitatively and quantitatively compare inner retinal morphology after the implantation of a PVA in two RP models: the Royal College of Surgeons (RCS) or transgenic S334ter-line 3 (S334ter-3) rhodopsin mutant rat. Two PVA designs were compared. In the RCS rat, we implanted devices in the subretinal space at 4 weeks of age and histologically examined them at 8 weeks of age and found inner retinal morphology preservation with both PVA devices. In the S334ter-3 rat, we implanted devices at 6-12 weeks of age and again, inner retinal morphology was generally preserved with either PVA design 16-26 weeks post-implantation. Specifically, the length of rod bipolar cells and numbers of cholinergic amacrine cells were maintained along with their characteristic inner plexiform lamination patterns. Throughout the implanted retinas we found nonspecific glial reaction, but none showed additional glial scarring at the implant site. Our results indicate that subretinally implanted PVAs are well-tolerated in rodent RP models and that the inner retinal circuitry is preserved, consistent with our published results showing implant-evoked signal transmission. Published

Cone dysfunctions in retinitis pigmentosa with retinal nerve fiber layer thickening

PubMed Central

Sobacı, Güngör; Özge, Gökhan; Gündoğan, Fatih Ç

2012-01-01

Purpose To investigate whether or not thicker retinal nerve fiber layer (RNFL) in retinitis pigmentosa (RP) patients relates to functional abnormalities of the photoreceptors. Methods Optical coherence tomography-based RNFL thickness was measured by Stratus-3™ (Zeiss, Basel, Switzerland) optical coherence tomography and electroretinogram (ERG) recordings made using the RETI-port® system (Roland, Wiesbaden, Germany) in 27 patients with retinitis pigmentosa and in 30 healthy subjects. Results Photopic ERG b-wave amplitude, cone ERG b-wave latency, 30 Hz flicker amplitude, and 30 Hz flicker latency had significant correlations to the RNFL-temporal (r = −0.55, P = 0.004, r = 0.68, P = 0.001, r = −0.65, P = 0.001, and r = −0.52, P = 0.007, respectively). Eyes with thicker RNFL (ten eyes) differed significantly from those with thinner RNFL (eight eyes) regarding cone ERG b-wave latency values only (P = 0.001). Conclusion Thicker RNFL in patients with retinitis pigmentosa may be associated with functional abnormality of the cone system. PMID:22536039

Changes in morphology of retinal ganglion cells with eccentricity in retinal degeneration.

PubMed

Anderson, E E; Greferath, U; Fletcher, E L

2016-05-01

Ganglion cells are the output neurons of the retina and are known to remodel during the subtle plasticity changes that occur following the death of photoreceptors in inherited retinal degeneration. We examine the influence of retinal eccentricity on anatomical remodelling and ganglion cell morphology well after photoreceptor loss. Rd1 mice that have a mutation in the β subunit of phosphodiesterase 6 were used as a model of retinal degeneration and gross remodelling events were examined by processing serial sections for immunocytochemistry. Retinal wholemounts from rd1-Thy1 and control Thy1 mice that contained a fluorescent protein labelling a subset of ganglion cells were processed for immunohistochemistry at 11 months of age. Ganglion cells were classified based on their soma size, dendritic field size and dendritic branching pattern and their dendritic fields were analysed for their length, area and quantity of branching points. Overall, more remodelling was found in the central compared with the peripheral retina. In addition, the size and complexity of A2, B1, C1 and D type ganglion cells located in the central region of the retina decreased. We propose that the changes in ganglion cell morphology are correlated with remodelling events in these regions and impact the function of retinal circuitry in the degenerated retina.

Peripheral retinal non-perfusion and treatment response in branch retinal vein occlusion.

PubMed

Abri Aghdam, Kaveh; Reznicek, Lukas; Soltan Sanjari, Mostafa; Framme, Carsten; Bajor, Anna; Klingenstein, Annemarie; Kernt, Marcus; Seidensticker, Florian

2016-01-01

To evaluate the association between the size of peripheral retinal non-perfusion and the number of intravitreal ranibizumab injections in patients with treatment-naive branch retinal vein occlusion (BRVO) and macular edema. A total of 53 patients with treatment-naive BRVO and macular edema were included. Each patient underwent a full ophthalmologic examination including optical coherence tomography (OCT) imaging and ultra wide-field fluorescein angiography (UWFA). Monthly intravitreal ranibizumab injections were applied according to the recommendations of the German Ophthalmological Society. Two independent, masked graders quantified the areas of peripheral retinal non-perfusion. Intravitreal injections improved best-corrected visual acuity (BCVA) significantly from 22.23±16.33 Early Treatment of Diabetic Retinopathy Study (ETDRS) letters to 36.23±15.19 letters (P<0.001), and mean central subfield thickness significantly reduced from 387±115 µm to 321±115 µm (P=0.01). Mean number of intravitreal ranibizumab injections was 3.61±1.56. The size of retinal non-perfusion correlated significantly with the number of intravitreal ranibizumab injections (R=0.724, P<0.001). Peripheral retinal non-perfusion in patients with BRVO associates significantly with intravitreal ranibizumab injections in patients with BRVO and macular edema.

Peripheral retinal non-perfusion and treatment response in branch retinal vein occlusion

PubMed Central

Abri Aghdam, Kaveh; Reznicek, Lukas; Soltan Sanjari, Mostafa; Framme, Carsten; Bajor, Anna; Klingenstein, Annemarie; Kernt, Marcus; Seidensticker, Florian

2016-01-01

AIM To evaluate the association between the size of peripheral retinal non-perfusion and the number of intravitreal ranibizumab injections in patients with treatment-naive branch retinal vein occlusion (BRVO) and macular edema. METHODS A total of 53 patients with treatment-naive BRVO and macular edema were included. Each patient underwent a full ophthalmologic examination including optical coherence tomography (OCT) imaging and ultra wide-field fluorescein angiography (UWFA). Monthly intravitreal ranibizumab injections were applied according to the recommendations of the German Ophthalmological Society. Two independent, masked graders quantified the areas of peripheral retinal non-perfusion. RESULTS Intravitreal injections improved best-corrected visual acuity (BCVA) significantly from 22.23±16.33 Early Treatment of Diabetic Retinopathy Study (ETDRS) letters to 36.23±15.19 letters (P<0.001), and mean central subfield thickness significantly reduced from 387±115 µm to 321±115 µm (P=0.01). Mean number of intravitreal ranibizumab injections was 3.61±1.56. The size of retinal non-perfusion correlated significantly with the number of intravitreal ranibizumab injections (R=0.724, P<0.001). CONCLUSION Peripheral retinal non-perfusion in patients with BRVO associates significantly with intravitreal ranibizumab injections in patients with BRVO and macular edema. PMID:27366688

Retinal vasculature classification using novel multifractal features

NASA Astrophysics Data System (ADS)

Ding, Y.; Ward, W. O. C.; Duan, Jinming; Auer, D. P.; Gowland, Penny; Bai, L.

2015-11-01

Retinal blood vessels have been implicated in a large number of diseases including diabetic retinopathy and cardiovascular diseases, which cause damages to retinal blood vessels. The availability of retinal vessel imaging provides an excellent opportunity for monitoring and diagnosis of retinal diseases, and automatic analysis of retinal vessels will help with the processes. However, state of the art vascular analysis methods such as counting the number of branches or measuring the curvature and diameter of individual vessels are unsuitable for the microvasculature. There has been published research using fractal analysis to calculate fractal dimensions of retinal blood vessels, but so far there has been no systematic research extracting discriminant features from retinal vessels for classifications. This paper introduces new methods for feature extraction from multifractal spectra of retinal vessels for classification. Two publicly available retinal vascular image databases are used for the experiments, and the proposed methods have produced accuracies of 85.5% and 77% for classification of healthy and diabetic retinal vasculatures. Experiments show that classification with multiple fractal features produces better rates compared with methods using a single fractal dimension value. In addition to this, experiments also show that classification accuracy can be affected by the accuracy of vessel segmentation algorithms.

Dengue and Dengue Hemorrhagic Fever

PubMed Central

Gubler, Duane J.

1998-01-01

Dengue fever, a very old disease, has reemerged in the past 20 years with an expanded geographic distribution of both the viruses and the mosquito vectors, increased epidemic activity, the development of hyperendemicity (the cocirculation of multiple serotypes), and the emergence of dengue hemorrhagic fever in new geographic regions. In 1998 this mosquito-borne disease is the most important tropical infectious disease after malaria, with an estimated 100 million cases of dengue fever, 500,000 cases of dengue hemorrhagic fever, and 25,000 deaths annually. The reasons for this resurgence and emergence of dengue hemorrhagic fever in the waning years of the 20th century are complex and not fully understood, but demographic, societal, and public health infrastructure changes in the past 30 years have contributed greatly. This paper reviews the changing epidemiology of dengue and dengue hemorrhagic fever by geographic region, the natural history and transmission cycles, clinical diagnosis of both dengue fever and dengue hemorrhagic fever, serologic and virologic laboratory diagnoses, pathogenesis, surveillance, prevention, and control. A major challenge for public health officials in all tropical areas of the world is to devleop and implement sustainable prevention and control programs that will reverse the trend of emergent dengue hemorrhagic fever. PMID:9665979

Multifocal lymphangioendotheliomatosis with devastating intracranial hemorrhage.

PubMed

Huang, Christina; Rizk, Elias; Iantosca, Mark; Zaenglein, Andrea L; Helm, Klaus F; Choudhary, Arabinda K; Dias, Mark S

2013-11-01

An in utero female was found to have a small hemorrhage at the foramen of Monro, hydrocephalus, and what was originally interpreted as a Dandy-Walker variant. At birth she had macrocephaly and numerous cutaneous, multifocal, red-pink blanchable macules. Postnatal MRI demonstrated a hemorrhagic soft-tissue mass involving the upper brainstem, thalamus, and basal ganglia most consistent with in utero complex multifocal intracranial hemorrhage. The skin lesions were thought to be consistent with multifocal lymphangioendotheliomatosis with thrombocytopenia (MLT). The size and location of the hemorrhage precluded operative intervention, although the hydrocephalus was treated with a ventricular shunt. The child continues to have severe developmental delays. Multifocal lymphangioendotheliomatosis with thrombocytopenia is a multifocal vascular disorder most commonly involving the skin and gastrointestinal tract. Intracranial hemorrhages are rare in this context. This case is the third reported instance of MLT with associated intracranial hemorrhage and the only case described in the neurosurgical literature. The authors review the presenting features and pathophysiology of this condition.

Microsystems Technology for Retinal Implants

NASA Astrophysics Data System (ADS)

Weiland, James

2005-03-01

The retinal prosthesis is targeted to treat age-related macular degeneration, retinitis pigmentosa, and other outer retinal degenerations. Simulations of artificial vision have predicted that 600-1000 individual pixels will be needed if a retinal prosthesis is to restore function such as reading large print and face recognition. An implantable device with this many electrode contacts will require microsystems technology as part of its design. An implantable retinal prosthesis will consist of several subsystems including an electrode array and hermetic packaging. Microsystems and microtechnology approaches are being investigated as possible solutions for these design problems. Flexible polydimethylsiloxane (PDMS) substrate electrode arrays and silicon micromachined electrode arrays are under development. Inactive PDMS electrodes have been implanted in 3 dogs to assess mechanical biocompatibility. 3 dogs were followed for 6 months. The implanted was securely fastened to the retina with a single retinal tack. No post-operative complications were evident. The array remained within 100 microns of the retinal surface. Histological evaluation showed a well preserved retina underneath the electrode array. A silicon device with electrodes suspended on micromachined springs has been implanted in 4 dogs (2 acute implants, 2 chronic implants). The device, though large, could be inserted into the eye and positioned on the retina. Histological analysis of the retina from the spring electrode implants showed that spring mounted posts penetrated the retina, thus the device will be redesigned to reduce the strength of the springs. These initial implants will provide information for the designers to make the next generation silicon device. We conclude that microsystems technology has the potential to make possible a retinal prosthesis with 1000 individual contacts in close proximity to the retina.

Management of obstetric hemorrhage.

PubMed

Shevell, Tracy; Malone, Fergal D

2003-02-01

A reluctance to proceed with hysterectomy for obstetric hemorrhage may be a more likely cause of preventable death in obstetrics than a lack of surgical or medical skills. Every obstetric unit should have protocols available to deal with hemorrhage and, in addition, have specific guidelines for patients who object to blood transfusions for various reasons. Risk factors for hemorrhage should be identified antenatally, using all possible imaging modalities available, and utilizing multidisciplinary resources whenever possible. Novel strategies for prenatal diagnosis of abnormal placentation include advanced sonography and magnetic resonance imaging. Placement and utilization of arterial catheters for uterine artery embolization is becoming more widespread and new surgical technology such as the argon beam coagulator seems promising. When intra or postpartum hemorrhage is encountered, a familiar protocol for dealing with blood loss should be triggered. Timely hysterectomy should be performed for signs of refractory bleeding. Application of medical and surgical principles combined with recent technologic advances will help the obstetrician avoid disastrous outcomes for both mother and fetus.

Microwave hemorrhagic stroke detector

DOEpatents

Haddad, Waleed S.; Trebes, James E.

2002-01-01

The microwave hemorrhagic stroke detector includes a low power pulsed microwave transmitter with a broad-band antenna for producing a directional beam of microwaves, an index of refraction matching cap placed over the patients head, and an array of broad-band microwave receivers with collection antennae. The system of microwave transmitter and receivers are scanned around, and can also be positioned up and down the axis of the patients head. The microwave hemorrhagic stroke detector is a completely non-invasive device designed to detect and localize blood pooling and clots or to measure blood flow within the head or body. The device is based on low power pulsed microwave technology combined with specialized antennas and tomographic methods. The system can be used for rapid, non-invasive detection of blood pooling such as occurs with hemorrhagic stroke in human or animal patients as well as for the detection of hemorrhage within a patient's body.

Microwave hemorrhagic stroke detector

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

Haddad, Waleed S; Trebes, James E

The microwave hemorrhagic stroke detector includes a low power pulsed microwave transmitter with a broad-band antenna for producing a directional beam of microwaves, an index of refraction matching cap placed over the patients head, and an array of broad-band microwave receivers with collection antennae. The system of microwave transmitter and receivers are scanned around, and can also be positioned up and down the axis of the patients head. The microwave hemorrhagic stroke detector is a completely non-invasive device designed to detect and localize blood pooling and clots or to measure blood flow within the head or body. The device ismore » based on low power pulsed microwave technology combined with specialized antennas and tomographic methods. The system can be used for rapid, non-invasive detection of blood pooling such as occurs with hemorrhagic stoke in human or animal patients as well as for the detection of hemorrhage within a patient's body.« less

“Post partum hemorrhage: causes and management”

PubMed Central

2013-01-01

Background Post partum hemorrhage is defined as blood loss of 500 ml or above. It is the most common cause of pre-mature mortality of women world wide. Our objective was to evaluate the most common etiology and method of management of Post partum Hemorrhage in a tertiary care hospital of Karachi. Findings It was a cross sectional study conducted at Liaquat National Hospital Karachi, during the period of July 2011 to May 2012. Review include mode of delivery, possible cause of postpartum hemorrhage, supportive, medical and surgical interventions. All the women admitted with post partum hemorrhage or develop PPH in hospital after delivery were included in our study. Bleeding disorder and use of anticoagulants were set as exclusion criteria. Diagnosis was made on the basis of blood loss assessment which was made via subjective and objective evaluation. During the targeted months, out of total 1493 deliveries (26/1493 = 1.741%) 26 cases of post partum hemorrhage were reported with a mean age of 26.153 ± 7.37. No deaths were reported and all cases were referred and unbooked cases. All Patients were conscious, tachycardiac and hypotensive. Most of the women were suffering from hemorrhage during or after the birth of their 1st child. Primary post partum hemorrhage emerge as the most common type of post partum hemorrhage and uterine atony was detected as the most common cause of primary post partum hemorrhage. Retained products of conception was the most common cause of secondary post partum hemorrhage and hysterectomy was found to be the most frequent method of management of post partum hemorrhage. Conclusion This study highlights the existing variable practices for the management of postpartum hemorrhage. Hemorrhage associated morbidity and mortality can be prevented by critical judgment, early referral and resuscitation by attendants. Introduction of an evidence-based management model can potentially reduce the practice variability and improve the quality of

Giant Retinal Tear With Retinal Detachment in Regressed Aggressive Posterior Retinopathy of Prematurity Treated by Laser.

PubMed

Chandra, Parijat; Tewari, Ruchir; Salunkhe, Nitesh; Kumawat, Devesh; Kumar, Vinod

2017-06-29

Rhegmatogenous retinal detachment after successfully regressed retinopathy of prematurity is a rare occurrence. Late onset rhegmatogenous retinal detachment has been reported infrequently. The authors report a case of aggressive posterior retinopathy of prematurity that underwent uneventful regression after laser photocoagulation and later developed an inoperable closed funnel retinal detachment due to a giant retinal tear. This case represents the earliest development of such complications in regressed aggressive posterior retinopathy of prematurity treated by laser. Development of a giant retinal tear has also not been previously reported after laser treatment. This case highlights that successful regression of severe retinopathy of prematurity does not safeguard against future complications and requires frequent long-term follow-up. [J Pediatr Ophthalmol Strabismus. 2017;54:e34-e36.]. Copyright 2017, SLACK Incorporated.

Incidence and risk factors for retinal vein occlusion at the University of Port Harcourt Teaching Hospital, Port Harcourt, Nigeria.

PubMed

Fiebai, B; Ejimadu, C S; Komolafe, R D

2014-01-01

The objective of the following study is to determine the incidence of retinal vein occlusion (RVO) and identify the risk factors in RVO in patients presenting to a tertiary hospital in Rivers State. The medical records of consecutive patients with RVO who presented to the retina clinic of the eye Department of University of Port Harcourt Teaching Hospital over a 5 year period were retrieved. Information extracted from the data included the demographic data of patients, presenting visual acuity, history of systemic and ocular disease, blood pressure and intraocular pressure. Data was analyzed using the Statistical Package for Social Sciences 20.0. (IBM Corporation and its licensors 1989,2011). Out of the 364 patients seen at the retina clinic during this period, 27 (7.4%) had RVO. Seven patients had bilateral disease. The incidence of RVO in the retinal clinic was 7.4%. Systemic hypertension, diabetes mellitus, hyperlipidemia and glaucoma were the main risk factors recorded in our patients. Central retinal vein occlusion (CRVO) 20 (74%) was more predominant than branch retinal vein occlusion (BRVO) 7 (26%). 21 eyes of patients with CRVO had visual acuities of < 3/60, while 7 eyes of patients with BRVO had visual acuities less than 3/60. Vitreous hemorrhage 10 (52.6%) was the most common complication encountered. All cases of non-perfused vein occlusion 4 (14.8%) were seen in patients who had CRVO. The incidence of RVO in our hospital is high. RVO is a significant cause of visual impairment, with CRVO being more common. Identifying associated risk factors and treating these could help reduce the incidence of RVO.

Enhanced generation of retinal progenitor cells from human retinal pigment epithelial cells induced by amniotic fluid

PubMed Central

2012-01-01

Background Retinal progenitor cells are a convenient source of cell replacement therapy in retinal degenerative disorders. The purpose of this study was to evaluate the expression patterns of the homeobox genes PAX6 and CHX10 (retinal progenitor markers) during treatment of human retinal pigment epithelium (RPE) cells with amniotic fluid (AF), RPE cells harvested from neonatal cadaver globes were cultured in a mixture of DMEM and Ham's F12 supplemented with 10% FBS. At different passages, cells were trypsinized and co-cultured with 30% AF obtained from normal fetuses of 1416 weeks gestational age. Results Compared to FBS-treated controls, AF-treated cultures exhibited special morphological changes in culture, including appearance of spheroid colonies, improved initial cell adhesion and ordered cell alignment. Cell proliferation assays indicated a remarkable increase in the proliferation rate of RPE cells cultivated in 30% AF-supplemented medium, compared with those grown in the absence of AF. Immunocytochemical analyses exhibited nuclear localization of retinal progenitor markers at a ratio of 33% and 27% for CHX10 and PAX6, respectively. This indicated a 3-fold increase in retinal progenitor markers in AF-treated cultures compared to FBS-treated controls. Real-time PCR data of retinal progenitor genes (PAX6, CHX10 and VSX-1) confirmed these results and demonstrated AF's capacity for promoting retinal progenitor cell generation. Conclusion Taken together, the results suggest that AF significantly promotes the rate of retinal progenitor cell generation, indicating that AF can be used as an enriched supplement for serum-free media used for the in vitro propagation of human progenitor cells. PMID:22490806

Automatic segmentation of pigment deposits in retinal fundus images of Retinitis Pigmentosa.

PubMed

Brancati, Nadia; Frucci, Maria; Gragnaniello, Diego; Riccio, Daniel; Di Iorio, Valentina; Di Perna, Luigi

2018-06-01

Retinitis Pigmentosa is an eye disease that presents with a slow loss of vision and then evolves until blindness results. The automatic detection of the early signs of retinitis pigmentosa acts as a great support to ophthalmologists in the diagnosis and monitoring of the disease in order to slow down the degenerative process. A large body of literature is devoted to the analysis of Retinitis Pigmentosa. However, all the existing approaches work on Optical Coherence Tomography (OCT) data, while hardly any attempts have been made working on fundus images. Fundus image analysis is a suitable tool in daily practice for an early detection of retinal diseases and the monitoring of their progression. Moreover, the fundus camera represents a low-cost and easy-access diagnostic system, which can be employed in resource-limited regions and countries. The fundus images of a patient suffering from retinitis pigmentosa are characterized by an attenuation of the vessels, a waxy disc pallor and the presence of pigment deposits. Considering that several methods have been proposed for the analysis of retinal vessels and the optic disk, this work focuses on the automatic segmentation of the pigment deposits in the fundus images. The image distortions are attenuated by applying a local pre-processing. Next, a watershed transformation is carried out to produce homogeneous regions. Working on regions rather than on pixels makes the method very robust to the high variability of pigment deposits in terms of color and shape, so allowing the detection even of small pigment deposits. The regions undergo a feature extraction procedure, so that a region classification process is performed by means of an outlier detection analysis and a rule set. The experiments have been performed on a dataset of images of patients suffering from retinitis pigmentosa. Although the images present a high variability in terms of color and illumination, the method provides a good performance in terms of

Superstition and post-tonsillectomy hemorrhage.

PubMed

Kumar, Veena V; Kumar, Naveen V; Isaacson, Glenn

2004-11-01

The objective was to determine whether post-tonsillectomy hemorrhages occur more frequently in redheaded children, in patterns of threes, on Friday-the-13th days, or with the full moon. Case-control analysis. The authors performed multiple statistical analyses of all children undergoing tonsillectomy at Temple University Children's Medical Center (Philadelphia, PA) during a 29-month period. Children readmitted to the hospital with or without surgical control of bleeding were compared with children who did not bleed. Relation of post-tonsillectomy hemorrhages to the phase of the moon was evaluated using a standard normal deviate. The frequency of surgery performed on Friday-the-13th days was compared with a differently dated Friday chosen at random. Clusters of three hemorrhages in a 7-day period were recorded. Families of children were contacted and asked whether their child had red hair. A chi analysis compared redheaded and non-redheaded tonsillectomy patients. Twenty-eight of 589 tonsillectomy cases performed required readmission for bleeding events. Twenty tonsillectomies occurred on a full-moon day, resulting in one bleeding event. One cluster of three post-tonsillectomy hemorrhages occurred in a 7-day period. Four of the children who bled had red hair. Two tonsillectomies occurred on Friday the 13th, with no associated hemorrhage. Statistical analysis revealed a random pattern to post-tonsillectomy hemorrhage. Post-tonsillectomy hemorrhages do not occur in clusters of three and are not more frequent with the full moon or on Friday the 13th. The bleeding rate among children with red hair is similar to that of non-redheaded children.

Bioelectronic retinal prosthesis

NASA Astrophysics Data System (ADS)

Weiland, James D.

2016-05-01

Retinal prosthesis have been translated to clinical use over the past two decades. Currently, two devices have regulatory approval for the treatment of retinitis pigmentosa and one device is in clinical trials for treatment of age-related macular degeneration. These devices provide partial sight restoration and patients use this improved vision in their everyday lives to navigate and to detect large objects. However, significant vision restoration will require both better technology and improved understanding of the interaction between electrical stimulation and the retina. In particular, current retinal prostheses do not provide peripheral visions due to technical and surgical limitations, thus limiting the effectiveness of the treatment. This paper reviews recent results from human implant patients and presents technical approaches for peripheral vision.

Role of Bax in death of uninfected retinal cells during murine cytomegalovirus retinitis.

PubMed

Mo, Juan; Marshall, Brendan; Covar, Jason; Zhang, Nancy Y; Smith, Sylvia B; Atherton, Sally S; Zhang, Ming

2014-10-08

Extensive death of uninfected bystander neuronal cells is an important component of the pathogenesis of cytomegalovirus retinitis. Our previous results have shown that caspase 3-dependent and -independent pathways are involved in death of uninfected bystander cells during murine cytomegalovirus (MCMV) retinitis and also that Bcl-2, an important inhibitor of apoptosis via the Bax-mediated mitochondrial pathway, is downregulated during this process. The purpose of this study was to determine whether Bax-mediated mitochondrial damage has a significant role in the death of uninfected retinal cells. BALB/c mice, Bax(-/-) mice, or Bax(+/+) mice were immunosuppressed with methylprednisolone and infected with 5 × 10(3) plaque-forming units (PFU) of the K181 strain of MCMV via the supraciliary route. Injected eyes were analyzed by plaque assay, electron microscopy, hematoxylin and eosin (H&E) staining, TUNEL assay, Western blot (for caspase 3, caspase 12, Bax, receptor interacting protein-1 [RIP1] and receptor interacting protein-3 [RIP3]), as well as immunohistochemical staining for MCMV early antigen and cleaved caspase 3. Significantly more Bax was detected in mitochondrial fractions of MCMV-infected eyes than in mitochondrial fractions of mock-infected control eyes. Furthermore, the level of cleaved caspase 3 was significantly lower in MCMV-infected Bax(-/-) eyes than in MCMV-infected Bax(+/+) eyes. However, more caspase 3-independent cell death of uninfected bystander retinal cells and more cleaved RIP1 were observed in Bax(-/-) than in Bax(+/+) eyes. During MCMV retinitis, Bax is activated and has an important role in death of uninfected bystander retinal cells by caspase 3-dependent apoptosis. Although the exact mechanism remains to be deciphered, active Bax might also prevent death of some types of uninfected retinal cells by a caspase 3-independent pathway. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

Role of Bax in Death of Uninfected Retinal Cells During Murine Cytomegalovirus Retinitis

PubMed Central

Mo, Juan; Marshall, Brendan; Covar, Jason; Zhang, Nancy Y.; Smith, Sylvia B.; Atherton, Sally S.; Zhang, Ming

2014-01-01

Purpose. Extensive death of uninfected bystander neuronal cells is an important component of the pathogenesis of cytomegalovirus retinitis. Our previous results have shown that caspase 3–dependent and –independent pathways are involved in death of uninfected bystander cells during murine cytomegalovirus (MCMV) retinitis and also that Bcl-2, an important inhibitor of apoptosis via the Bax-mediated mitochondrial pathway, is downregulated during this process. The purpose of this study was to determine whether Bax-mediated mitochondrial damage has a significant role in the death of uninfected retinal cells. Methods. BALB/c mice, Bax−/− mice, or Bax+/+ mice were immunosuppressed with methylprednisolone and infected with 5 × 103 plaque-forming units (PFU) of the K181 strain of MCMV via the supraciliary route. Injected eyes were analyzed by plaque assay, electron microscopy, hematoxylin and eosin (H&E) staining, TUNEL assay, Western blot (for caspase 3, caspase 12, Bax, receptor interacting protein-1 [RIP1] and receptor interacting protein-3 [RIP3]), as well as immunohistochemical staining for MCMV early antigen and cleaved caspase 3. Results. Significantly more Bax was detected in mitochondrial fractions of MCMV-infected eyes than in mitochondrial fractions of mock-infected control eyes. Furthermore, the level of cleaved caspase 3 was significantly lower in MCMV-infected Bax−/− eyes than in MCMV-infected Bax+/+ eyes. However, more caspase 3–independent cell death of uninfected bystander retinal cells and more cleaved RIP1 were observed in Bax−/− than in Bax+/+ eyes. Conclusions. During MCMV retinitis, Bax is activated and has an important role in death of uninfected bystander retinal cells by caspase 3–dependent apoptosis. Although the exact mechanism remains to be deciphered, active Bax might also prevent death of some types of uninfected retinal cells by a caspase 3–independent pathway. PMID:25298417

Vitreous vascular endothelial growth factor concentrations in proliferative diabetic retinopathy versus proliferative vitreoretinopathy.

PubMed

Citirik, Mehmet; Kabatas, Emrah Utku; Batman, Cosar; Akin, Kadir Okhan; Kabatas, Naciye

2012-01-01

To assess vitreous vascular endothelial growth factor (VEGF) concentrations in proliferative diabetic retinopathy (PDR) in comparison to proliferative vitreoretinopathy (PVR). Vitreous samples were collected from 69 eyes of 69 patients with traumatic lens dislocation (n = 10), grade B PVR with rhegmatogenous retinal detachment (n = 13), grade C PVR with rhegmatogenous retinal detachment (n = 14), PDR with vitreous hemorrhage (n = 18), and PDR with vitreous hemorrhage and tractional retinal detachment (n = 14). Vitreous fluid samples were obtained at vitrectomy, and the levels of VEGF were measured by enzyme-linked immunosorbent assay. The mean vitreous level of VEGF was 15.14 ± 5.22 pg/ml in eyes with grade B PVR, 99.15 ± 38.58 pg/ml in eyes with grade C PVR, 4,534.01 ± 1,193.28 pg/ml in eyes with vitreous hemorrhage secondary to PDR, 5,157.29 ± 969.44 pg/ml in eyes with vitreous hemorrhage and tractional retinal detachment secondary to PDR, and 16.19 ± 5.76 pg/ml in eyes of the control group with traumatic lens dislocation. Vitreous VEGF concentrations were significantly higher in the patients with grade C PVR, PDR with vitreous hemorrhage and PDR with vitreous hemorrhage and tractional retinal detachment in comparison to the control patients (p < 0.05). A significant alteration was not observed in patients with grade B PVR (p = 0.55). Vitreous VEGF concentrations are increased in PDR and grade C PVR. The high VEGF concentrations could suggest a possible effect of VEGF on advanced PVR. Copyright © 2011 S. Karger AG, Basel.

Tractional retinal detachment in Usher syndrome type II.

PubMed

Rani, Alka; Pal, Nikhil; Azad, Raj Vardhan; Sharma, Yog Raj; Chandra, Parijat; Vikram Singh, Deependra

2005-08-01

Retinal detachment is a rare complication in patients with retinitis pigmentosa. A case is reported of tractional retinal detachment in a patient with retinitis pigmentosa and sensorineural hearing loss, which was diagnosed as Usher syndrome type II. Because of the poor visual prognosis, the patient refused surgery in that eye. Tractional retinal detachment should be added to the differential diagnoses of visual loss in patients with retinitis pigmentosa.

Inherited Retinal Degenerative Disease Registry

ClinicalTrials.gov

2017-09-13

Eye Diseases Hereditary; Retinal Disease; Achromatopsia; Bardet-Biedl Syndrome; Bassen-Kornzweig Syndrome; Batten Disease; Best Disease; Choroidal Dystrophy; Choroideremia; Cone Dystrophy; Cone-Rod Dystrophy; Congenital Stationary Night Blindness; Enhanced S-Cone Syndrome; Fundus Albipunctatus; Goldmann-Favre Syndrome; Gyrate Atrophy; Juvenile Macular Degeneration; Kearns-Sayre Syndrome; Leber Congenital Amaurosis; Refsum Syndrome; Retinitis Pigmentosa; Retinitis Punctata Albescens; Retinoschisis; Rod-Cone Dystrophy; Rod Dystrophy; Rod Monochromacy; Stargardt Disease; Usher Syndrome

Ruptured retinal arterial macroaneurysm: diagnosis and management.

PubMed

Speilburg, Ashley M; Klemencic, Stephanie A

2014-01-01

Retinal arterial macroaneurysm is an acquired, focal dilation of a retinal artery, typically occurring within the first three bifurcations of the central retinal artery. The clinical presentation of a retinal arterial macroaneurysm is highly variable, making initial diagnosis difficult and differentials many. Identification of retinal arterial macroaneurysms is crucial to appropriately co-manage with the primary care physician for hypertension control. Prognosis is generally good and observation is often an adequate treatment. However, in cases of macular threat or involvement, some treatment options are available and referral to a retinal specialist is indicated. Copyright © 2013 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

Retinal abnormalities in β-thalassemia major.

PubMed

Bhoiwala, Devang L; Dunaief, Joshua L

2016-01-01

Patients with beta (β)-thalassemia (β-TM: β-thalassemia major, β-TI: β-thalassemia intermedia) have a variety of complications that may affect all organs, including the eye. Ocular abnormalities include retinal pigment epithelial degeneration, angioid streaks, venous tortuosity, night blindness, visual field defects, decreased visual acuity, color vision abnormalities, and acute visual loss. Patients with β-thalassemia major are transfusion dependent and require iron chelation therapy to survive. Retinal degeneration may result from either retinal iron accumulation from transfusion-induced iron overload or retinal toxicity induced by iron chelation therapy. Some who were never treated with iron chelation therapy exhibited retinopathy, and others receiving iron chelation therapy had chelator-induced retinopathy. We will focus on retinal abnormalities present in individuals with β-thalassemia major viewed in light of new findings on the mechanisms and manifestations of retinal iron toxicity. Copyright © 2016 Elsevier Inc. All rights reserved.

Viral hemorrhagic septicemia

USGS Publications Warehouse

Batts, William N.; Winton, James R.

2012-01-01

Viral hemorrhagic septicemia (VHS) is one of the most important viral diseases of finfish worldwide. In the past, VHS was thought to affect mainly rainbow trout Oncorhynchus mykiss reared at freshwater facilities in Western Europe where it was known by various names including Egtved disease and infectious kidney swelling and liver degeneration (Wolf 1988). Today, VHS is known as an important source of mortality for cultured and wild fish in freshwater and marine environments in several regions of the northern hemisphere (Dixon 1999; Gagné et al. 2007; Kim and Faisal 2011; Lumsden et al. 2007; Marty et al. 1998, 2003; Meyers and Winton 1995; Skall et al. 2005b; Smail 1999; Takano et al. 2001). Viral hemorrhagic septicemia is caused by the fish rhabdovirus, viral hemorrhagic septicemia virus (VHSV), a member of the genus Novirhabdovirus of the family Rhabdoviridae

Decreased Retinal-Choroidal Blood Flow in Retinitis Pigmentosa as measured by MRI

PubMed Central

Zhang, Yi; Harrison, Joseph M; Nateras, Oscar San Emeterio; Chalfin, Steven; Duong, Timothy Q

2013-01-01

Purpose To evaluate retinal and choroidal blood flow (BF) using high-resolution magnetic resonance imaging (MRI) as well as visual function measured by the electroretinogram (ERG) in patients with retinitis pigmentosa (RP). Methods MRI studies were performed in 6 RP patients (29-67 years) and 5 healthy volunteers (29-64 years) on a 3-Tesla scanner with a custom-made surface coil. Quantitative BF was measured using the pseudo-continuous arterial-spin-labeling technique at 0.5x0.8x6.0mm. Full-field ERGs of all patients were recorded. Amplitudes and implicit times of standard ERGs were analyzed. Results Basal BF in the posterior retinal-choroid was 142±16 ml/100ml/min (or 1.14±0.13 μl/mm2/min) in the control group and was 70±19 ml/100ml/min (or 0.56±0.15 μl/mm2/min) in the RP group. Retinal-choroidal BF was significantly reduced by 52±8% in RP patients compared to controls (P<0.05). ERG a- and b-wave amplitudes of RP patients were reduced and b-wave implicit times were delayed. There were statistically significant correlations between a-wave amplitude and BF value (r=0.9, P<0.05) but not between b-wave amplitude and BF value (r =0.7, P=0.2). Conclusions This study demonstrates a novel non-invasive MRI approach to measure quantitative retinal and choroidal BF in RP patients. We found that retinal-choroidal BF was markedly reduced and significantly correlated with reduced amplitudes of the a-wave of the standard combined ERG. PMID:23408312

Changing Trends in Surgery for Retinal Detachment in Korea

PubMed Central

Cho, Ga Eun; Kim, Seong Wook

2014-01-01

Purpose To analyze trends in rhegmatogenous retinal detachment (RRD) surgery among the members of the Korean Retina Society from 2001 to 2013. Methods In 2013, surveys were conducted by email and post to investigate the current practice patterns regarding RRD treatment. Questions included how surgeons would manage six cases of hypothetical RRD. Results were compared to those reported in 2001. Results A total of 133 members (60.7%) in 2013 and 46 members(79.3%) in 2001 responded to the survey. Preference for pneumatic retinopexy has decreased in uncomplicated primary RRD (p = 0.004). More respondents in 2013 selected vitrectomy as the primary procedure when mild vitreous hemorrhage (p = 0.001), myopia (p = 0.044) and history of successful scleral buckling on the fellow eye (p = 0.044) were added to the primary scenario. Vitrectomy was over twice as popular in cases of pseudophakic, macula-off RRD with posterior capsular opacity (p = 0.001). Conclusions For RRD with myopia, pseudophakia and media opacity, surgical interventions over the last decade have drastically shifted from scleral buckling and pneumatic retinopexy to vitrectomy. PMID:25435747

Acral Hemorrhagic Darier Disease.

PubMed

Flores-Terry, M Á; García-Arpa, M; Llamas-Velasco, M; Mendoza-Chaparro, C; Ramos-Rodríguez, C

2017-09-01

Darier disease is an autosomal-dominant inherited condition caused by mutation of a gene, which produces a protein involved in calcium channel regulation. The disease has a variety of manifestations and lacks consistent genotype-phenotype correlations. Acral hemorrhagic Darier disease causes macules, papules, vesicles and/or hemorrhagic blisters on the extremities. Other classic signs of the disease may be present in the same patient or relatives. Histopathology reveals dyskeratosis and suprabasal acantholysis with hemorrhagic lacunae. We report 3 new cases of this type of Darier disease triggered by injuries. Response to retinoid therapy was good. Copyright © 2017 AEDV. Publicado por Elsevier España, S.L.U. All rights reserved.

[Retinal vasculitis and systemic diseases].

PubMed

Gascon, P; Jarrot, P-A; Matonti, F; Kaplanski, G

2018-06-19

Retinal vasculitis (RV) is an inflammation of retinal blood vessels that can be associated with uveitis or be isolated, and can induce vascular occlusion and retinal ischemia. Visual acuity can be severely affected in case of macular involvement or neovessel formation. The diagnosis relies on fundoscopy and fluorescein angiography. Systemic diseases may be associated with RV, the most frequently encountered are Behçet's disease, sarcoidosis or multiple sclerosis, all predominantly associated with venous involvement, whereas systemic lupus erythematosus and necrotizing vasculitis are less frequently observed and predominantly associated with arterial or mixed vasculitis. Treatments are usually aggressive in order to preserve a good visual acuity and to reduce retinal inflammation and chronic ischemia. Steroids, immunosuppressive drugs, retinal laser photocoagulation, intravitreal anti-VEGF injections are usual treatments and more recently, anti-TNFalpha monoclonal therapeutic antibodies have been shown to be very successful. Copyright © 2018 Société Nationale Française de Médecine Interne (SNFMI). Published by Elsevier Masson SAS. All rights reserved.

Expression Profiling Analysis Reveals Key MicroRNA-mRNA Interactions in Early Retinal Degeneration in Retinitis Pigmentosa.

PubMed

Anasagasti, Ander; Ezquerra-Inchausti, Maitane; Barandika, Olatz; Muñoz-Culla, Maider; Caffarel, María M; Otaegui, David; López de Munain, Adolfo; Ruiz-Ederra, Javier

2018-05-01

The aim of this study was to identify differentially expressed microRNAs (miRNAs) that might play an important role in the etiology of retinal degeneration in a genetic mouse model of retinitis pigmentosa (rd10 mice) at initial stages of the disease. miRNAs-mRNA interaction networks were generated for analysis of biological pathways involved in retinal degeneration. Of more than 1900 miRNAs analyzed, we selected 19 miRNAs on the basis of (1) a significant differential expression in rd10 retinas compared with control samples and (2) an inverse expression relationship with predicted mRNA targets involved in biological pathways relevant to retinal biology and/or degeneration. Seven of the selected miRNAs have been associated with retinal dystrophies, whereas, to our knowledge, nine have not been previously linked to any disease. This study contributes to our understanding of the etiology and progression of retinal degeneration.

Concentric retinitis pigmentosa: clinicopathologic correlations.

PubMed

Milam, A H; De Castro, E B; Smith, J E; Tang, W X; John, S K; Gorin, M B; Stone, E M; Aguirre, G D; Jacobson, S G

2001-10-01

Progressive concentric (centripetal) loss of vision is one pattern of visual field loss in retinitis pigmentosa. This study provides the first clinicopathologic correlations for this form of retinitis pigmentosa. A family with autosomal dominant concentric retinitis pigmentosa was examined clinically and with visual function tests. A post-mortem eye of an affected 94 year old family member was processed for histopathology and immunocytochemistry with retinal cell specific antibodies. Unrelated simplex/multiplex patients with concentric retinitis pigmentosa were also examined. Affected family members of the eye donor and patients from the other families had prominent peripheral pigmentary retinopathy with more normal appearing central retina, good visual acuity, concentric field loss, normal or near normal rod and cone sensitivity within the preserved visual field, and reduced rod and cone electroretinograms. The eye donor, at age 90, had good acuity and function in a central island. Grossly, the central region of the donor retina appeared thinned but otherwise normal, while the far periphery contained heavy bone spicule pigment. Microscopically the central retina showed photoreceptor outer segment shortening and some photoreceptor cell loss. The mid periphery had a sharp line of demarcation where more central photoreceptors were near normal except for very short outer segments and peripheral photoreceptors were absent. Rods and cones showed abrupt loss of outer segments and cell death at this interface. It is concluded that concentric retinitis pigmentosa is a rare but recognizable phenotype with slowly progressive photoreceptor death from the far periphery toward the central retina. The disease is retina-wide but shows regional variation in severity of degeneration; photoreceptor death is severe in the peripheral retina with an abrupt edge between viable and degenerate photoreceptors. Peripheral to central gradients of unknown retinal molecule(s) may be defective

Determination of retinal surface area.

PubMed

Nagra, Manbir; Gilmartin, Bernard; Thai, Ngoc Jade; Logan, Nicola S

2017-09-01

Previous attempts at determining retinal surface area and surface area of the whole eye have been based upon mathematical calculations derived from retinal photographs, schematic eyes and retinal biopsies of donor eyes. 3-dimensional (3-D) ocular magnetic resonance imaging (MRI) allows a more direct measurement, it can be used to image the eye in vivo, and there is no risk of tissue shrinkage. The primary purpose of this study is to compare, using T2-weighted 3D MRI, retinal surface areas for superior-temporal (ST), inferior-temporal (IT), superior-nasal (SN) and inferior-nasal (IN) retinal quadrants. An ancillary aim is to examine whether inter-quadrant variations in area are concordant with reported inter-quadrant patterns of susceptibility to retinal breaks associated with posterior vitreous detachment (PVD). Seventy-three adult participants presenting without retinal pathology (mean age 26.25 ± 6.06 years) were scanned using a Siemens 3-Tesla MRI scanner to provide T2-weighted MR images that demarcate fluid-filled internal structures for the whole eye and provide high-contrast delineation of the vitreous-retina interface. Integrated MRI software generated total internal ocular surface area (TSA). The second nodal point was used to demarcate the origin of the peripheral retina in order to calculate total retinal surface area (RSA) and quadrant retinal surface areas (QRSA) for ST, IT, SN, and IN quadrants. Mean spherical error (MSE) was -2.50 ± 4.03D and mean axial length (AL) 24.51 ± 1.57 mm. Mean TSA and RSA for the RE were 2058 ± 189 and 1363 ± 160 mm 2 , respectively. Repeated measures anova for QRSA data indicated a significant difference within-quadrants (P < 0.01) which, contrasted with ST (365 ± 43 mm 2 ), was significant for IT (340 ± 40 mm 2 P < 0.01), SN (337 ± 40 mm 2 P < 0.01) and IN (321 ± 39 mm 2 P < 0.01) quadrants. For all quadrants, QRSA was significantly correlated with AL (P < 0.01) and exhibited

Evaluation of the Zeiss retinal vessel analyser

PubMed Central

Polak, K.; Dorner, G.; Kiss, B.; Polska, E.; Findl, O.; Rainer, G.; Eichler, H.; Schmetterer, L.

2000-01-01

AIM—To investigate the reproducibility and sensitivity of the Zeiss retinal vessel analyser, a new method for the online determination of retinal vessel diameters in healthy subjects.
METHODS—Two model drugs were administered, a peripheral vasoconstrictor (the α receptor agonist phenylephrine) and a peripheral vasodilator (the nitric oxide donor sodium nitroprusside) in stepwise increasing doses. Nine healthy young subjects were studied in a placebo controlled double masked three way crossover design. Subjects received intravenous infusions of either placebo or stepwise increasing doses of phenylephrine (0.5, 1, or 2 µg/kg/min) or sodium nitroprusside (0.5, 1, or 2 µg/kg/min). Retinal vessel diameters were measured with the new Zeiss retinal vessel analyser. Retinal leucocyte velocity, flow, and density were measured with the blue field entoptic technique. The reproducibility of measurements was assessed with coefficients of variation and intraclass correlation coefficients.
RESULTS—Placebo and phenylephrine did not influence retinal haemodynamics, although the α receptor antagonist significantly increased blood pressure. Sodium nitroprusside induced a significant increase in retinal venous and arterial diameters (p<0.001 each), leucocyte density (p=0.001), and leucocyte flow (p=0.024) despite lowering blood pressure to a significant degree. For venous and arterial vessel size measurements short term coefficients of variation were 1.3% and 2.6% and intraclass correlation coefficients were 0.98 and 0.96, respectively. The sensitivity was between 3% and 5% for retinal veins and 5% and 7% for retinal arteries.
CONCLUSIONS—These data indicate that the Zeiss retinal vessel analyser is an accurate system for the assessment of retinal diameters in healthy subjects. In addition, nitric oxide appears to have a strong influence on retinal vascular tone.

 PMID:11049956

Inferior retinal light exposure is more effective than superior retinal exposure in suppressing melatonin in humans

NASA Technical Reports Server (NTRS)

Glickman, Gena; Hanifin, John P.; Rollag, Mark D.; Wang, Jenny; Cooper, Howard; Brainard, George C.

2003-01-01

Illumination of different areas of the human retina elicits differences in acute light-induced suppression of melatonin. The aim of this study was to compare changes in plasma melatonin levels when light exposures of equal illuminance and equal photon dose were administered to superior, inferior, and full retinal fields. Nine healthy subjects participated in the study. Plexiglass eye shields were modified to permit selective exposure of the superior and inferior halves of the retinas of each subject. The Humphrey Visual Field Analyzer was used both to confirm intact full visual fields and to quantify exposure of upper and lower visual fields. On study nights, eyes were dilated, and subjects were exposed to patternless white light for 90 min between 0200 and 0330 under five conditions: (1) full retinal exposure at 200 lux, (2) full retinal exposure at 100 lux, (3) inferior retinal exposure at 200 lux, (4) superior retinal exposure at 200 lux, and (5) a dark-exposed control. Plasma melatonin levels were determined by radioimmunoassay. ANOVA demonstrated a significant effect of exposure condition (F = 5.91, p < 0.005). Post hoc Fisher PLSD tests showed significant (p < 0.05) melatonin suppression of both full retinal exposures as well as the inferior retinal exposure; however, superior retinal exposure was significantly less effective in suppressing melatonin. Furthermore, suppression with superior retinal exposure was not significantly different from that of the dark control condition. The results indicate that the inferior retina contributes more to the light-induced suppression of melatonin than the superior retina at the photon dosages tested in this study. Findings suggest a greater sensitivity or denser distribution of photoreceptors in the inferior retina are involved in light detection for the retinohypothalamic tract of humans.

INTERNAL LIMITING MEMBRANE PEELING-DEPENDENT RETINAL STRUCTURAL CHANGES AFTER VITRECTOMY IN RHEGMATOGENOUS RETINAL DETACHMENT.

PubMed

Hisatomi, Toshio; Tachibana, Takashi; Notomi, Shoji; Koyanagi, Yoshito; Murakami, Yusuke; Takeda, Atsunobu; Ikeda, Yasuhiro; Yoshida, Shigeo; Enaida, Hiroshi; Murata, Toshinori; Sakamoto, Taiji; Sonoda, Koh-Hei; Ishibashi, Tatsuro

2018-03-01

To examine retinal changes after vitrectomy with internal limiting membrane (ILM) peeling, we used 3-dimensional optical coherence tomography (3D-OCT) in rhegmatogenous retinal detachment cases. The 68 eyes from 67 patients with rhegmatogenous retinal detachment were studied, including 35 detached macula cases (51%) and 33 attached macula cases. Internal limiting membrane peeling was performed with fine forceps after brilliant blue G staining. The 3D-OCT images were obtained with volume-rendering technologies from cross-sectional OCT images. The 3D-OCT detected 45 eyes (66%) with ILM peeling-dependent retinal changes, including dissociated optic nerve fiber layer appearance, dimple sign, temporal macular thinning, ILM peeling area thinning, or forceps-related retinal thinning. The ILM peeled area was detectable in only 9 eyes with 3D-OCT, whereas it was undetectable in other 59 eyes. The dissociated optic nerve fiber layer appearance was detected in 8 of the total cases (12%), and dimple signs were observed in 14 cases (21%). Forceps-related thinning was also noted in eight cases (24%) of attached macula cases and in four cases (11%) of detached macula cases. No postoperative macular pucker was noted in the observational period. The 3D-OCT clearly revealed spatial and time-dependent retinal changes after ILM peeling. The changes occurred in 2 months and remained thereafter.

HIF-1α stabilization reduces retinal degeneration in a mouse model of retinitis pigmentosa.

PubMed

Olivares-González, Lorena; Martínez-Fernández de la Cámara, Cristina; Hervás, David; Millán, José María; Rodrigo, Regina

2018-05-01

Retinitis pigmentosa (RP) is a group of inherited retinal dystrophies characterized by progressive and irreversible loss of vision due to rod and cone degeneration. Evidence suggests that an inappropriate oxygen level could contribute to its pathogenesis. Rod cell death could increase oxygen concentration, reduce hypoxia-inducible factor 1 (HIF-1α) and contribute to cone cell death. The purposes of this study were: 1) to analyze the temporal profile of HIF-1α, its downstream effectors VEGF, endothelin-1 (ET-1), iNOS, and glucose transporter 1 (GLUT1), and neuroinflammation in retinas of the murine model of rd10 ( retinal degeneration 10) mice with RP; 2) to study oxygen bioavailability in these retinas; and 3) to investigate how stabilizing HIF-1α proteins with dimethyloxaloglycine (DMOG), a prolyl hydroxylase inhibitor, affects retinal degeneration, neuroinflammation, and antioxidant response in rd10 mice. A generalized down-regulation of HIF-1α and its downstream targets was detected in parallel with reactive gliosis, suggesting high oxygen levels during retinal degeneration. At postnatal d 18, DMOG treatment reduced photoreceptor cell death and glial activation. In summary, retinas of rd10 mice seem to be exposed to a hyperoxic environment even at early stages of degeneration. HIF-1α stabilization could have a temporal neuroprotective effect on photoreceptor cell survival, glial activation, and antioxidant response at early stages of RP.-Olivares-González, L., Martínez-Fernández de la Cámara, C., Hervás, D., Millán, J. M., Rodrigo, R. HIF-1α stabilization reduces retinal degeneration in a mouse model of retinitis pigmentosa.

Focal posterior pole viral retinitis.

PubMed

Hazirolan, Dicle; Sungur, Gulten; Demir, Necati; Kasim, Remzi; Duman, Sunay

2010-01-01

To describe the clinical features of an atypical form of viral retinitis in immunocompetent patients. This was a retrospective noncomparative case series. The charts of 8 patients diagnosed with and treated for focal posterior viral retinitis were reviewed. Clinical and demographic features were evaluated. All the patients had extensive laboratory tests, fundus fluorescein angiography, optical coherence tomography of macula, and polymerase chain reaction of vitreous. All the patients were referred to our Uveitis Service from other hospitals, as their uveitis symptoms deteriorated in spite of treatment. The mean age of 4 male and 4 female patients was 32.1 years (range, 22-42 years). The mean follow-up period was 10 months (range, 6-18 months). All of the patients had unilateral disease. Polymerase chain reaction analysis of vitreous specimen was positive for herpes simplex virus-1 in 5 patients and varicella zoster virus in 3 patients. Retinitis resolved after systemic acyclovir treatment in all patients. Viral etiology must be borne in mind in the differential diagnosis of atypical retinitis. It can be a milder form of viral retinitis like focal viral retinitis, as mentioned in this study. The prognosis of this disease is better than the other forms of necrotizing retinopathies involving a larger area of retina.

Filling in the retinal image

NASA Technical Reports Server (NTRS)

Larimer, James; Piantanida, Thomas

1990-01-01

The optics of the eye form an image on a surface at the back of the eyeball called the retina. The retina contains the photoreceptors that sample the image and convert it into a neural signal. The spacing of the photoreceptors in the retina is not uniform and varies with retinal locus. The central retinal field, called the macula, is densely packed with photoreceptors. The packing density falls off rapidly as a function of retinal eccentricity with respect to the macular region and there are regions in which there are no photoreceptors at all. The retinal regions without photoreceptors are called blind spots or scotomas. The neural transformations which convert retinal image signals into percepts fills in the gaps and regularizes the inhomogeneities of the retinal photoreceptor sampling mosaic. The filling-in mechamism plays an important role in understanding visual performance. The filling-in mechanism is not well understood. A systematic collaborative research program at the Ames Research Center and SRI in Menlo Park, California, was designed to explore this mechanism. It was shown that the perceived fields which are in fact different from the image on the retina due to filling-in, control some aspects of performance and not others. Researchers have linked these mechanisms to putative mechanisms of color coding and color constancy.

Intravitreal Anti Vascular Endothelial Growth Factor Agents in The Management of Retinal Diseases: An Audit.

PubMed

Fiebai, Bassey; Odogu, Victor

2017-01-01

The study aimed to describe our initial experience with the use of anti vascular endothelial growth factors (anti-VEGFs) in the treatment of retinal diseases. The case records of all patients who had received at least 3 doses of intravitreal anti- VEGF injections between January 2012 to December 2016 were reviewed. Information culled from the data was age, sex, indications for treatment, type of injection, presenting visual acuity, post injection visual acuity, systemic and ocular co morbidities. Results were analyzed using Statistical Package for Social Sciences (SPSS) 20.0 for Windows statistical software. A total of 190 injections were given during the study period, to 58 eyes of 50 patients. Twenty-eight females (56.00%) and twenty-two males (44.00%) were seen with a mean age of 59.6± 11.66. Bevacizumab was the most frequently administered anti- VEGF, 142 (74.74%) while only 48(25.26%) injections of Ranibizumab were given. Three eyes had both bevacizumab and ranibizumab (1.58%). Retinal vein occlusion 61(32.11%) was the commonest indication for the injections followed by diabetic macular edema 43(22.63%) and proliferative diabetic retinopathy 42(22.11%). Others were neovascular age related macular degeneration, neovascular glaucoma, vitreous hemorrhage, myopic choroidal neovascularization and cystoid macular edema. There was an association between age and disease, (p = 0.001). There was an improvement in visual acuity after intervention in cases with retinal vein occlusion and diabetic macular edema, and this was statistically significant. Hypertension was the commonest systemic disorder in this series 81(42.36%) and the supero-temporal quadrant 131(68.95%) was the most preferred position to administer the injection. Floaters was the commonest complication seen. Anti VEGFs have become an invaluable tool in the management of a number of retinal diseases in our center. However, the cost implications are a hindrance to an increased uptake of this form of

Intraventricular hemorrhage of the newborn

MedlinePlus

... page: //medlineplus.gov/ency/article/007301.htm Intraventricular hemorrhage of the newborn To use the sharing features on this page, please enable JavaScript. Intraventricular hemorrhage (IVH) of the newborn is bleeding into the ...

Massive postpartum right renal hemorrhage.

PubMed

Kiracofe, H L; Peterson, N

1975-06-01

All reported cases of massive postpartum right renal hemorrhage have involved healthy young primigravidas and blacks have predominated (4 of 7 women). Coagulopathies and underlying renal disease have been absent. Hematuria was painless in 5 of 8 cases. Hemorrhage began within 24 hours in 1 case, within 48 hours in 4 cases and 4 days post partum in 3 cases. Our first case is the only report in which hemorrhage has occurred in a primipara. Failure of closure or reopening of pyelovenous channels is suggested as the pathogenesis. The hemorrhage has been self-limiting, requiring no more than 1,500 cc whole blood replacement. Bleeding should stop spontaneously, and rapid renal pelvic clot lysis should follow with maintenance of adequate urine output and Foley catheter bladder decompression. To date surgical intervention has not been necessary.

Expression Profiling Analysis Reveals Key MicroRNA–mRNA Interactions in Early Retinal Degeneration in Retinitis Pigmentosa

PubMed Central

Anasagasti, Ander; Ezquerra-Inchausti, Maitane; Barandika, Olatz; Muñoz-Culla, Maider; Caffarel, María M.; Otaegui, David; López de Munain, Adolfo

2018-01-01

Purpose The aim of this study was to identify differentially expressed microRNAs (miRNAs) that might play an important role in the etiology of retinal degeneration in a genetic mouse model of retinitis pigmentosa (rd10 mice) at initial stages of the disease. Methods miRNAs–mRNA interaction networks were generated for analysis of biological pathways involved in retinal degeneration. Results Of more than 1900 miRNAs analyzed, we selected 19 miRNAs on the basis of (1) a significant differential expression in rd10 retinas compared with control samples and (2) an inverse expression relationship with predicted mRNA targets involved in biological pathways relevant to retinal biology and/or degeneration. Seven of the selected miRNAs have been associated with retinal dystrophies, whereas, to our knowledge, nine have not been previously linked to any disease. Conclusions This study contributes to our understanding of the etiology and progression of retinal degeneration. PMID:29847644

Crimean-Congo Hemorrhagic Fever (CCHF)

MedlinePlus

... Congo Hemorrhagic Fever (CCHF) [PDF – 2 pages] Virus Ecology Viral Hemorrhagic Fever (VHF) Information for Specific Groups ... Diagnosis Treatment Prevention Outbreak Distribution Map Resources Virus Ecology File Formats Help: How do I view different ...

Retinal Laminar Architecture in Human Retinitis Pigmentosa Caused by Rhodopsin Gene Mutations

PubMed Central

Aleman, Tomas S.; Cideciyan, Artur V.; Sumaroka, Alexander; Windsor, Elizabeth A. M.; Herrera, Waldo; White, D. Alan; Kaushal, Shalesh; Naidu, Anjani; Roman, Alejandro J.; Schwartz, Sharon B.; Stone, Edwin M.; Jacobson, Samuel G.

2008-01-01

Purpose. To determine the underlying retinal micropathology in subclasses of autosomal dominant retinitis pigmentosa (ADRP) caused by rhodopsin (RHO) mutations. Methods. Patients with RHO-ADRP (n = 17, ages 6–73 years), representing class A (R135W and P347L) and class B (P23H, T58R, and G106R) functional phenotypes, were studied with optical coherence tomography (OCT), and colocalized visual thresholds were determined by dark- and light-adapted chromatic perimetry. Autofluorescence imaging was performed with near-infrared light. Retinal histology in hT17M-rhodopsin mice was compared with the human results. Results. Class A patients had only cone-mediated vision. The outer nuclear layer (ONL) thinned with eccentricity and was not detectable within 3 to 4 mm of the fovea. Scotomatous extracentral retina showed loss of ONL, thickening of the inner retina, and demelanization of RPE. Class B patients had superior–inferior asymmetry in function and structure. The superior retina could have normal rod and cone vision, normal lamination (including ONL) and autofluorescence of the RPE melanin; laminopathy was found in the scotomas. With Fourier-domain-OCT, there was apparent inner nuclear layer (INL) thickening in regions with ONL thinning. Retinal regions without ONL had a thick hyporeflective layer that was continuous with the INL from neighboring regions with normal lamination. Transgenic mice had many of the laminar abnormalities found in patients. Conclusions. Retinal laminar abnormalities were present in both classes of RHO-ADRP and were related to the severity of colocalized vision loss. The results in human class B and the transgenic mice support the following disease sequence: ONL diminution with INL thickening; amalgamation of residual ONL with the thickened INL; and progressive retinal remodeling with eventual thinning. PMID:18385078

Hemorrhage Detection and Segmentation in Traumatic Pelvic Injuries

PubMed Central

Davuluri, Pavani; Wu, Jie; Tang, Yang; Cockrell, Charles H.; Ward, Kevin R.; Najarian, Kayvan; Hargraves, Rosalyn H.

2012-01-01

Automated hemorrhage detection and segmentation in traumatic pelvic injuries is vital for fast and accurate treatment decision making. Hemorrhage is the main cause of deaths in patients within first 24 hours after the injury. It is very time consuming for physicians to analyze all Computed Tomography (CT) images manually. As time is crucial in emergence medicine, analyzing medical images manually delays the decision-making process. Automated hemorrhage detection and segmentation can significantly help physicians to analyze these images and make fast and accurate decisions. Hemorrhage segmentation is a crucial step in the accurate diagnosis and treatment decision-making process. This paper presents a novel rule-based hemorrhage segmentation technique that utilizes pelvic anatomical information to segment hemorrhage accurately. An evaluation measure is used to quantify the accuracy of hemorrhage segmentation. The results show that the proposed method is able to segment hemorrhage very well, and the results are promising. PMID:22919433

Subconjunctival Hemorrhage (Broken Blood Vessel in Eye)

MedlinePlus

Subconjunctival hemorrhage (broken blood vessel in eye) Overview A subconjunctival hemorrhage (sub-kun-JUNK-tih-vul HEM-uh-ruj) ... may not even realize you have a subconjunctival hemorrhage until you look in the mirror and notice ...

Novel method for edge detection of retinal vessels based on the model of the retinal vascular network and mathematical morphology

NASA Astrophysics Data System (ADS)

Xu, Lei; Zheng, Xiaoxiang; Zhang, Hengyi; Yu, Yajun

1998-09-01

Accurate edge detection of retinal vessels is a prerequisite for quantitative analysis of subtle morphological changes of retinal vessels under different pathological conditions. A novel method for edge detection of retinal vessels is presented in this paper. Methods: (1) Wavelet-based image preprocessing. (2) The signed edge detection algorithm and mathematical morphological operation are applied to get the approximate regions that contain retinal vessels. (3) By convolving the preprocessed image with a LoG operator only on the detected approximate regions of retinal vessels, followed by edges refining, clear edge maps of the retinal vessels are fast obtained. Results: A detailed performance evaluation together with the existing techniques is given to demonstrate the strong features of our method. Conclusions: True edge locations of retinal vessels can be fast detected with continuous structures of retinal vessels, less non- vessel segments left and insensitivity to noise. The method is also suitable for other application fields such as road edge detection.

Comprehensive analysis of mouse retinal mononuclear phagocytes.

PubMed

Lückoff, Anika; Scholz, Rebecca; Sennlaub, Florian; Xu, Heping; Langmann, Thomas

2017-06-01

The innate immune system is activated in a number of degenerative and inflammatory retinal disorders such as age-related macular degeneration (AMD). Retinal microglia, choroidal macrophages, and recruited monocytes, collectively termed 'retinal mononuclear phagocytes', are critical determinants of ocular disease outcome. Many publications have described the presence of these cells in mouse models for retinal disease; however, only limited aspects of their behavior have been uncovered, and these have only been uncovered using a single detection method. The workflow presented here describes a comprehensive analysis strategy that allows characterization of retinal mononuclear phagocytes in vivo and in situ. We present standardized working steps for scanning laser ophthalmoscopy of microglia from MacGreen reporter mice (mice expressing the macrophage colony-stimulating factor receptor GFP transgene throughout the mononuclear phagocyte system), quantitative analysis of Iba1-stained retinal sections and flat mounts, CD11b-based retinal flow cytometry, and qRT-PCR analysis of key microglia markers. The protocol can be completed within 3 d, and we present data from retinas treated with laser-induced choroidal neovascularization (CNV), bright white-light exposure, and Fam161a-associated inherited retinal degeneration. The assays can be applied to any of the existing mouse models for retinal disorders and may be valuable for documenting immune responses in studies for immunomodulatory therapies.

Ebola hemorrhagic Fever.

PubMed

Burnett, Mark W

2014-01-01

Ebola hemorrhagic fever is an often-fatal disease caused by a virus of the Filoviridae family, genus Ebolavirus. Initial signs and symptoms of the disease are nonspecific, often progressing on to a severe hemorrhagic illness. Special Operations Forces Medical Providers should be aware of this disease, which occurs in sporadic outbreaks throughout Africa. Treatment at the present time is mainly supportive. Special care should be taken to prevent contact with bodily fluids of those infected, which can transmit the virus to caregivers. 2014.

Clinically undetected retinal breaks causing retinal detachment: A review of options for management.

PubMed

Gupta, Deepak; Ching, Jared; Tornambe, Paul E

2017-08-12

The successful detection of retinal breaks is a critical step in rhegmatogenous retinal detachment surgery in order to prevent persistent/recurrent retinal detachments. Not all retinal breaks causing retinal detachments are obvious. Retinal breaks may be obscured by opacities that are either anterior segment related, lens related, or posterior segment related. Rules to identify breaks based on subretinal fluid configuration are more difficult to apply in pseudophakic, aphakic, and scleral buckle encircled eyes-and in eyes with repeat detachments and those with proliferative vitreoretinopathy. Exudative detachments exhibit characteristic features and must be ruled out. A thorough clinical examination preoperatively is important even if a vitrectomy is planned. We review the incidence and causes of undetected breaks, along with preoperative/clinical issues that may hinder break detection. We review the literature with respect to investigative approaches and techniques that are available to the vitreoretinal surgeon when primary breaks remain clinically undetected during the preoperative examination. We broadly divide the surgical approaches into ones where the surgeon utilizes techniques to pursue actively a search for breaks versus adopting a purely speculative approach. Advantages and disadvantages of various techniques are appraised. Intuitively one might argue that an encircling scleral buckle combined with vitrectomy would give higher single operation success than pars plana vitrectomy alone because "undetected" retinal breaks would be addressed by a 360° plombage. We could not confirm this concept. Newer techniques, such as pars plana vitrectomy augmented with dye extrusion or endoscopic-assisted pars plana vitrectomy, show encouraging results. Technological advances such as intraoperative optical coherence tomography will also help to broaden the vitreoretinal surgeon's armamentarium. At this time, there is no gold standard in terms of the recommended

Vocal fold hemorrhage: factors predicting recurrence.

PubMed

Lennon, Christen J; Murry, Thomas; Sulica, Lucian

2014-01-01

Vocal fold hemorrhage is an acute phonotraumatic injury treated with voice rest; recurrence is a generally accepted indication for surgical intervention. This study aims to identify factors predictive of recurrence based on outcomes of a large clinical series. Retrospective cohort. Retrospective review of cases of vocal fold hemorrhage presenting to a university laryngology service. Demographic information was compiled. Videostroboscopic exams were evaluated for hemorrhage extent, presence of varix, mucosal lesion, and/or vocal fold paresis. Vocal fold hemorrhage recurrence was the main outcome measure. Follow-up telephone survey was used to complement clinical data. Forty-seven instances of vocal fold hemorrhage were evaluated (25M:22F; 32 professional voice users). Twelve of the 47 (26%) patients experienced recurrence. Only the presence of varix demonstrated significant association with recurrence (P = 0.0089) on multivariate logistic regression. Vocal fold hemorrhage recurred in approximately 26% of patients. Varix was a predictor of recurrence, with 48% of those with varix experiencing recurrence. Monitoring, behavioral management and/or surgical intervention may be indicated to treat patients with such characteristics. © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

[Cilioretinal artery occlusion and central retinal vein occlusion complicating hyperhomocysteinemia: a case report].

PubMed

Berkani, Z; Kitouni, Y; Belhadj, A; Sifi, K; Abbadi, N; Bellatrache, C; Hartani, D; Kherroubi, R

2013-09-01

Hyperhomocysteinemia is known to be a risk factor in both retinal artery and retinal vein occlusions. We report the case of a young patient with combined occlusion of the cilioretinal artery and the central retinal vein due to hyperhomocysteinemia. A 23-year-old patient without significant medical history, presented for sudden, painless visual loss in the right eye. Ophthalmologic examination revealed best-corrected visual acuity of the right eye 8/10 P2, and 10/10 P2 on the left. Anterior segment exam was normal in both eyes, while the right fundus revealed white, ischemic edema, centered around a cilioretinal artery, sparing the fovea, with some hemorrhagic spots and disc edema. Fluorescein angiography confirmed delayed filling of the right cilioretinal artery and revealed a normal disc on the left. Two weeks later, the clinical picture had evolved into a right ischemic CRVO, confirmed by a second angiogram, with a decrease in visual acuity to 3/10. A work-up was performed, including: a full lipid profile, serum electrolytes, ESR, CRP, a complete blood count (leukocytes, platelets, hemoglobin were normal), a coagulation work-up (PT, PTT, protein C, protein S, antithrombin III, factor V Leiden were normal), ANCA, antiphospholipid antibodies and antinuclear antibodies were negative, and finally cardiology studies (cardiac echo, carotid Doppler) and neurology (brain MRI) were ordered and came back normal. Otherwise, plasma homocysteine was moderately high on two samples, at 18.3 μmol/L and 17.78 μmol/L. Thyroid and renal work-ups were ordered. Urgent PRP was performed, and vitamin therapy (vitB12, vitB6, folic acid) was instituted. The subsequent course was remarkable for recovery of visual acuity to 10/10, P2 with persistence of an inferior altitudinal central scotoma. MTHFR C677T polymorphism was negative. Retinal vascular occlusions (RVO) are serious events, which require investigation for underlying systemic disease, which can be life-threatening. The clinical

[CT diagnosis of hemorrhagic renal cysts].

PubMed

Wu, Y Z; Li, D T; Luo, J G

2001-06-28

CT signs of nineteen cases of hemorrhagic renal cysts that surgically and pathologically proved were analyzed. 8 of the 19 cases revealed as high density hemorrhagic lesion. CT signs in those 8 patients include low density rim sign, cyst immerging sign, and perirenal fascia thickening. The other 11 of 19 cases revealed as low density lesion. CT signs include thickened cyst wall and inhomogeneous density of the cystic content. The hounsfield unit of the lesion is correlated with the duration of disease. It is suggested that CT is valuable in diagnosis of high density hemorrhagic renal cysts, and it gives a clue to the diagnosis of low density hemorrhagic renal cysts.

OPTICAL COHERENCE TOMOGRAPHY FINDINGS IN CYTOMEGALOVIRUS RETINITIS: A Longitudinal Study.

PubMed

Invernizzi, Alessandro; Agarwal, Aniruddha; Ravera, Vittoria; Oldani, Marta; Staurenghi, Giovanni; Viola, Francesco

2018-01-01

To evaluate the vitreal, retinal, and choroidal features using spectral domain optical coherence tomography (SD-OCT) in eyes affected by cytomegalovirus (CMV) retinitis. Patients diagnosed with either active or inactive CMV retinitis were included in the study. Complete ophthalmic examination, serial color fundus photography, and SD-OCT (with and without enhanced depth imaging function) were performed for all the subjects at baseline and follow-up visits. The SD-OCT images were analyzed by two independent graders to evaluate the structural changes in areas of CMV retinitis. Prevalence data for vitreal, retinal, and choroidal SD-OCT features were collected. Twelve eyes from 9 patients (6 males, mean age: 52.7 ± 10.3 years) were enrolled. Nine eyes were diagnosed with active CMV retinitis at baseline. Active disease SD-OCT characteristic findings included nebulous vitritis (100%), posterior hyaloid thickening (83.3%), epiretinal membrane (100%), and retinal swelling (100%). Two distinct patterns of chorioretinal involvement were observed in active retinitis: 1) full-thickness retinitis (Full thickness retinitis) (n = 7 eyes) with choriocapillaris alterations and retinal pigment epithelial thickening and 2) cavernous retinitis (n = 3 eyes) characterized by inner retinal hyperreflectivity, large empty spaces in outer nuclear layer, and bridges of retinal tissue but retinal pigment epithelium and choriocapillaris sparing. Patients with cavernous retinitis develop retinal detachment during follow-up. Eyes with Full thickness retinitis developed choriocapillaris atrophy and choroidal thinning and retinal scars as the lesions healed. There are two distinct patterns of chorioretinal involvement in CMV retinitis. SD-OCT is a useful tool in the diagnosis, management, and prediction of the outcome of CMV retinitis.

Retinal Prosthesis System for Advanced Retinitis Pigmentosa: A Health Technology Assessment Update

PubMed Central

Lee, Christine; Tu, Hong Anh; Wells, David; Holubowich, Corinne

2017-01-01

Background Retinitis pigmentosa is a group of inherited disorders characterized by the degeneration of the photoreceptors in the retina, resulting in progressive vision loss. The Argus II system is designed to restore partial functional vision in patients with profound vision loss from advanced retinitis pigmentosa. At present, it is the only treatment option approved by Health Canada for this patient population. In June 2016, Health Quality Ontario published a health technology assessment of the Argus II retinal prosthesis system for patients with advanced retinitis pigmentosa. Based on that assessment, the Ontario Health Technology Advisory Committee recommended against publicly funding the Argus II system for this population. It also recommended that Health Quality Ontario re-evaluate the evidence in 1 year. The objective of this report was to examine new evidence published since the 2016 health technology assessment. Methods We completed a health technology assessment, which included an evaluation of clinical benefits and harms, value for money, and patient preferences related to the Argus II system. We performed a systematic literature search for studies published since the 2016 Argus II health technology assessment. We developed a Markov decision-analytic model to assess the cost-effectiveness of the Argus II system compared with standard care, and we calculated incremental cost-effectiveness ratios over a 20-year time horizon. We also conducted a five-year budget impact analysis. Finally, we interviewed people with retinitis pigmentosa about their lived experience with vision loss, and with the Argus II system. Results Four publications from one multicentre international study were included in the clinical review. Patients showed significant improvements in visual function and functional outcomes with the Argus II system, and these outcomes were sustained up to a 5-year follow-up (moderate quality of evidence). The safety profile was generally acceptable. In

Vocal fold varices and risk of hemorrhage.

PubMed

Tang, Christopher Guan-Zhong; Askin, Gülce; Christos, Paul J; Sulica, Lucian

2016-05-01

To establish risk of hemorrhage in patients with varices compared to those without, determine additional risk factors, and make evidence-based treatment recommendations. Retrospective cohort study. Patients who were vocal performers presenting for care during a 24-month period were analyzed to determine incidence of hemorrhage. Patients with varices were compared to those without. Demographic information and examination findings (presence, location, character, and size of varices; presence of mucosal lesions or paresis) were analyzed to determine predictors of hemorrhage. A total of 513 patients (60.4% female, mean age 36.6 years ± 13.95 years) were evaluated; 14 patients presenting with hemorrhage were excluded. One hundred and twelve (22.4%) patients had varices; 387 (77.6%) did not. The rate of hemorrhage in patients with varices was 2.68% at 12 months compared to 0.8% in patients without. Cox proportional hazard regression analysis revealed a hazard ratio of 10.1 for patients with varix developing hemorrhage compared to nonvarix patients (P < 0.0001). The incidence rate of hemorrhage was 3.3 cases per 1,000 person-months for varix patients compared to 0.5 cases per 1,000 person-months in the nonvarix group. There was no significant difference in the incidence of paresis, mucosal lesions, location of varix (left or right side; medial or lateral), or varix morphology (pinpoint, linear, lake) between patients who hemorrhaged and those that did not. The presence of varices increases the risk of hemorrhage. Varix patients had 10 times the rate of hemorrhage compared to nonvarix patients, although the overall incidence is low. This data may be used to inform treatment of patients with varices. 4. Laryngoscope, 126:1163-1168, 2016. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

Survey on diagnosis of diseases from retinal images

NASA Astrophysics Data System (ADS)

Das, Sneha; Malathy, C.

2018-04-01

Retina is a thin membranous layer of tissue that occupies at the back of the eye which provides central vision needed for daily routines. Identifying retinal diseases at the early stage is a challenging task since healthy retina is required for central vision. Several retinal diseases affect the eye such as retinal tear, retinal detachment, glaucoma, macular hole and macular degeneration etc. These maladies will encounter a secondary growth in the close future as the age of the person increases. A survey is made which tells about the diagnosis of the retinal diseases from the retinal images using machine learning techniques.

Retinal Effects Of Blue Light Exposure

NASA Astrophysics Data System (ADS)

Ham, William T.; Mueller, Harold A.; Ruffolo, J. J.

1980-10-01

Recent research has shown that blue light exposure is an important factor in certain types of retinal injury. The mammalian ocular media transmits the spectral band 400-1400 nm to the retina. The short wavelengths (400-550 nm) produce a photochemical or actinic type of damage, while the longer wavelengths (550-1400 nm) produce thermal damage. Distinction between the two types of retinal damage are discussed briefly and the importance of the blue light effect for solar retinitis and eclipse blindness is emphasized. The significance of blue light retinal injury is summarized for various environmental and occupational exposures.

Relation of retinal blood flow and retinal oxygen extraction during stimulation with diffuse luminance flicker

PubMed Central

Palkovits, Stefan; Lasta, Michael; Told, Reinhard; Schmidl, Doreen; Werkmeister, René; Cherecheanu, Alina Popa; Garhöfer, Gerhard; Schmetterer, Leopold

2015-01-01

Cerebral and retinal blood flow are dependent on local neuronal activity. Several studies quantified the increase in cerebral blood flow and oxygen consumption during activity. In the present study we investigated the relation between changes in retinal blood flow and oxygen extraction during stimulation with diffuse luminance flicker and the influence of breathing gas mixtures with different fractions of O2 (FiO2; 100% 15% and 12%). Twenty-four healthy subjects were included. Retinal blood flow was studied by combining measurement of vessel diameters using the Dynamic Vessel Analyser with measurements of blood velocity using laser Doppler velocimetry. Oxygen saturation was measured using spectroscopic reflectometry and oxygen extraction was calculated. Flicker stimulation increased retinal blood flow (57.7 ± 17.8%) and oxygen extraction (34.6 ± 24.1%; p < 0.001 each). During 100% oxygen breathing the response of retinal blood flow and oxygen extraction was increased (p < 0.01 each). By contrast, breathing gas mixtures with 12% and 15% FiO2 did not alter flicker–induced retinal haemodynamic changes. The present study indicates that at a comparable increase in blood flow the increase in oxygen extraction in the retina is larger than in the brain. During systemic hyperoxia the blood flow and oxygen extraction responses to neural stimulation are augmented. The underlying mechanism is unknown. PMID:26672758

Scleral electrocautery and its effects on choroid vessels: implications for subretinal fluid drainage during scleral buckling surgery.

PubMed

Roybal, C Nathaniel; Tsui, Irena; Sanfilippo, Christian; Hubschman, Jean-Pierre

2013-01-01

External drainage of subretinal fluid as part of a scleral buckling procedure rapidly restores the retinal pigment epithelium-neural retina interface in rhegmatogenous retinal detachments but carries the inherent risk of subretinal hemorrhage and retinal incarceration. The authors investigated variations to the technique to reduce the chance of subretinal hemorrhage originating from the choroid. A novel method for needle drainage using electrocautery of the sclerochoroidal layers before puncture was employed. The effect of 0% to 50% scleral electrocautery in a porcine model was investigated. A significant decrease in choroidal vessel diameter and choroidal vessel density at 40% electrocautery was demonstrated. Electrocautery without scleral cut-down before external drainage of subretinal fluid likely decreases the chance of subretinal hemorrhage by decreasing choroidal vascularity. Copyright 2013, SLACK Incorporated.

Acute retinal ischemia inhibits endothelium-dependent nitric oxide-mediated dilation of retinal arterioles via enhanced superoxide production.

PubMed

Hein, Travis W; Ren, Yi; Potts, Luke B; Yuan, Zhaoxu; Kuo, Enoch; Rosa, Robert H; Kuo, Lih

2012-01-03

Because retinal vascular disease is associated with ischemia and increased oxidative stress, the vasodilator function of retinal arterioles was examined after retinal ischemia induced by elevated intraocular pressure (IOP). The role of superoxide anions in the development of vascular dysfunction was assessed. IOP was increased and maintained at 80 to 90 mm Hg for 30, 60, or 90 minutes by infusing saline into the anterior chamber of a porcine eye. The fellow eye with normal IOP (10-20 mm Hg) served as control. In some pigs, superoxide dismutase mimetic TEMPOL (1 mM) or vehicle (saline) was injected intravitreally before IOP elevation. After enucleation, retinal arterioles were isolated and pressurized without flow for functional analysis by recording diameter changes using videomicroscopic techniques. Dihydroethidium (DHE) was used to detect superoxide production in isolated retinal arterioles. Isolated retinal arterioles developed stable basal tone and the vasodilations to endothelium-dependent nitric oxide (NO)-mediated agonists bradykinin and L-lactate were significantly reduced only by 90 minutes of ischemia. However, vasodilation to endothelium-independent NO donor sodium nitroprusside was unaffected after all time periods of ischemia. DHE staining showed that 90 minutes of ischemia significantly increased superoxide levels in retinal arterioles. Intravitreal injection of membrane-permeable radical scavenger but not vehicle before ischemia prevented elevation of vascular superoxide and preserved bradykinin-induced dilation. Endothelium-dependent NO-mediated dilation of retinal arterioles is impaired by 90 minutes of ischemia induced by elevated IOP. The inhibitory effect appears to be mediated by the alteration of NO signaling via vascular superoxide.

Detection of retinal lesions in diabetic retinopathy: comparative evaluation of 7-field digital color photography versus red-free photography.

PubMed

Venkatesh, Pradeep; Sharma, Reetika; Vashist, Nagender; Vohra, Rajpal; Garg, Satpal

2015-10-01

Red-free light allows better detection of vascular lesions as this wavelength is absorbed by hemoglobin; however, the current gold standard for the detection and grading of diabetic retinopathy remains 7-field color fundus photography. The goal of this study was to compare the ability of 7-field fundus photography using red-free light to detect retinopathy lesions with corresponding images captured using standard 7-field color photography. Non-stereoscopic standard 7-field 30° digital color fundus photography and 7-field 30° digital red-free fundus photography were performed in 200 eyes of 103 patients with various grades of diabetic retinopathy ranging from mild to moderate non-proliferative diabetic retinopathy to proliferative diabetic retinopathy. The color images (n = 1,400) were studied with corresponding red-free images (n = 1,400) by one retina consultant (PV) and two senior residents training in retina. The various retinal lesions [microaneurysms, hemorrhages, hard exudates, soft exudates, intra-retinal microvascular anomalies (IRMA), neovascularization of the retina elsewhere (NVE), and neovascularization of the disc (NVD)] detected by all three observers in each of the photographs were noted followed by determination of agreement scores using κ values (range 0-1). Kappa coefficient was categorized as poor (≤0), slight (0.01-0.20), fair (0.2 -0.40), moderate (0.41-0.60), substantial (0.61-0.80), and almost perfect (0.81-1). The number of lesions detected by red-free images alone was higher for all observers and all abnormalities except hard exudates. Detection of IRMA was especially higher for all observers with red-free images. Between image pairs, there was substantial agreement for detection of hard exudates (average κ = 0.62, range 0.60-0.65) and moderate agreement for detection of hemorrhages (average κ = 0.52, range 0.45-0.58), soft exudates (average κ = 0.51, range 0.42-0.61), NVE (average κ = 0.47, range 0.39-0.53), and NVD

Management of intracerebral hemorrhage.

PubMed

Thabet, A M; Kottapally, M; Hemphill, J Claude

2017-01-01

Intracerebral hemorrhage (ICH) is a potentially devastating neurologic injury representing 10-15% of stroke cases in the USA each year. Numerous risk factors, including age, hypertension, male gender, coagulopathy, genetic susceptibility, and ethnic descent, have been identified. Timely identification, workup, and management of this condition remain a challenge for clinicians as numerous factors can present obstacles to achieving good functional outcomes. Several large clinical trials have been conducted over the prior decade regarding medical and surgical interventions. However, no specific treatment has shown a major impact on clinical outcome. Current management guidelines do exist based on medical evidence and consensus and these provide a framework for care. While management of hypertension and coagulopathy are generally considered basic tenets of ICH management, a variety of measures for surgical hematoma evacuation, intracranial pressure control, and intraventricular hemorrhage can be further pursued in the emergent setting for selected patients. The complexity of management in parenchymal cerebral hemorrhage remains challenging and offers many areas for further investigation. A systematic approach to the background, pathology, and early management of spontaneous parenchymal hemorrhage is provided. © 2017 Elsevier B.V. All rights reserved.

Transcorneal Electrical Stimulation Therapy for Retinal Disease

ClinicalTrials.gov

2012-05-03

Retinitis Pigmentosa; Macula Off; Primary Open Angle Glaucoma; Hereditary Macular Degeneration; Treated Retina Detachment; Retinal Artery Occlusion; Retinal Vein Occlusion; Non-Arthritic-Anterior-Ischemic Optic-Neuropathy; Hereditary Autosomal Dominant Optic Atrophy; Dry Age Related Macular Degeneration; Ischemic Macula Edema

Fetomaternal hemorrhage during external cephalic version.

PubMed

Boucher, Marc; Marquette, Gerald P; Varin, Jocelyne; Champagne, Josette; Bujold, Emmanuel

2008-07-01

To estimate the frequency and volume of fetomaternal hemorrhage during external cephalic version for term breech singleton fetuses and to identify risk factors involved with this complication. A prospective observational study was performed including all patients undergoing a trial of external cephalic version for a breech presentation of at least 36 weeks of gestation between 1987 and 2001 in our center. A search for fetal erythrocytes using the standard Kleihauer-Betke test was obtained before and after each external cephalic version. The frequency and volume of fetomaternal hemorrhage were calculated. Putative risk factors for fetomaternal hemorrhage were evaluated by chi(2) test and Mann-Whitney U test. A Kleihauer-Betke test result was available before and after 1,311 trials of external cephalic version. The Kleihauer-Betke test was positive in 67 (5.1%) before the procedure. Of the 1,244 women with a negative Kleihauer-Betke test before external cephalic version, 30 (2.4%) had a positive Kleihauer-Betke test after the procedure. Ten (0.8%) had an estimated fetomaternal hemorrhage greater than 1 mL, and one (0.08%) had an estimated fetomaternal hemorrhage greater than 30 mL. The risk of fetomaternal hemorrhage was not influenced by parity, gestational age, body mass index, number of attempts at version, placental location, or amniotic fluid index. The risk of detectable fetomaternal hemorrhage during external cephalic version was 2.4%, with fetomaternal hemorrhage more than 30 mL in less than 0.1% of cases. These data suggest that the performance of a Kleihauer-Betke test is unwarranted in uneventful external cephalic version and that in Rh-negative women, no further Rh immune globulin is necessary other than the routine 300-microgram dose at 28 weeks of gestation and postpartum. II.

Inherited Retinal Degenerative Clinical Trial Network

DTIC Science & Technology

2009-10-01

ending in blindness. In the United States, the total number of individuals affected by retinitis pigmentosa (RP) and other forms of rare inherited...AD_________________ AWARD NUMBER: W81XWH-07-1-0720 TITLE: Inherited Retinal Degenerative...Final 3. DATES COVERED 27 Sep 2007 – 29 Sep 2009 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Inherited Retinal Degenerative Clinical Trial Network

Retinal Structure Measurements as Inclusion Criteria for Stem Cell-Based Therapies of Retinal Degenerations.

PubMed

Jacobson, Samuel G; Matsui, Rodrigo; Sumaroka, Alexander; Cideciyan, Artur V

2016-04-01

We reviewed and illustrated the most optimal retinal structural measurements to make in stem cell clinical trials. Optical coherence tomography (OCT) and autofluorescence (AF) imaging were used to evaluate patients with severe visual loss from nonsyndromic and syndromic retinitis pigmentosa (RP), ABCA4-Stargardt disease, and nonneovascular age-related macular degeneration (AMD). Outer nuclear layer (ONL), rod outer segment (ROS) layer, inner retina, ganglion cell layer (GCL), and nerve fiber layer (NFL) thicknesses were quantified. All patients had severely reduced visual acuities. Retinitis pigmentosa patients had limited visual fields; maculopathy patients had central scotomas with retained peripheral function. For the forms of RP illustrated, there was detectable albeit severely reduced ONL across the scanned retina, and normal or hyperthick GCL and NFL. Maculopathy patients had no measurable ONL centrally; it became detectable with eccentricity. Some maculopathy patients showed unexpected GCL losses. Autofluorescence imaging illustrated central losses of RPE integrity. A hypothetical scheme to relate patient data with different phases of retinal remodeling in animal models of retinal degeneration was presented. Stem cell science is advancing, but it is not too early to open the discussion of criteria for patient selection and monitoring. Available clinical tools, such as OCT and AF imaging, can provide inclusion/exclusion criteria and robust objective outcomes. Accepting that early trials may not lead to miraculous cures, we should be prepared to know why-scientifically and clinically-so we can improve subsequent trials. We also must determine if retinal remodeling is an impediment to efficacy.

Pilot Study of Optical Coherence Tomography Measurement of Retinal Blood Flow in Retinal and Optic Nerve Diseases

PubMed Central

Wang, Yimin; Fawzi, Amani A.; Varma, Rohit; Sadun, Alfredo A.; Zhang, Xinbo; Tan, Ou; Izatt, Joseph A.

2011-01-01

Purpose. To investigate blood flow changes in retinal and optic nerve diseases with Doppler Fourier domain optical coherence tomography (OCT). Methods. Sixty-two participants were divided into five groups: normal, glaucoma, nonarteritic ischemic optic neuropathy (NAION), treated proliferative diabetic retinopathy (PDR), and branch retinal vein occlusion (BRVO). Doppler OCT was used to scan concentric circles of 3.4- and 3.75-mm diameters around the optic nerve head. Flow in retinal veins was calculated from the OCT velocity profiles. Arterial and venous diameters were measured from OCT Doppler and reflectance images. Results. Total retinal blood flow in normal subjects averaged 47.6 μL/min. The coefficient of variation of repeated measurements was 11% in normal eyes and 14% in diseased eyes. Eyes with glaucoma, NAION, treated PDR, and BRVO had significantly decreased retinal blood flow compared with normal eyes (P < 0.001). In glaucoma patients, the decrease in blood flow was highly correlated with the severity of visual field loss (P = 0.003). In NAION and BRVO patients, the hemisphere with more severe disease also had lower blood flow. Conclusions. Doppler OCT retinal blood flow measurements showed good repeatability and excellent correlation with visual field and clinical presentations. This approach could enhance our understanding of retinal and optic nerve diseases and facilitate the development of new therapies. PMID:21051715

ACUTE RETINAL ARTERIAL OCCLUSIVE DISORDERS

PubMed Central

Hayreh, Sohan Singh

2011-01-01

The initial section deals with basic sciences; among the various topics briefly discussed are the anatomical features of ophthalmic, central retinal and cilioretinal arteries which may play a role in acute retinal arterial ischemic disorders. Crucial information required in the management of central retinal artery occlusion (CRAO) is the length of time the retina can survive following that. An experimental study shows that CRAO for 97 minutes produces no detectable permanent retinal damage but there is a progressive ischemic damage thereafter, and by 4 hours the retina has suffered irreversible damage. In the clinical section, I discuss at length various controversies on acute retinal arterial ischemic disorders. Classification of acute retinal arterial ischemic disorders These are of 4 types: CRAO, branch retinal artery occlusion (BRAO), cotton wools spots and amaurosis fugax. Both CRAO and BRAO further comprise multiple clinical entities. Contrary to the universal belief, pathogenetically, clinically and for management, CRAO is not one clinical entity but 4 distinct clinical entities – non-arteritic CRAO, non-arteritic CRAO with cilioretinal artery sparing, arteritic CRAO associated with giant cell arteritis (GCA) and transient non-arteritic CRAO. Similarly, BRAO comprises permanent BRAO, transient BRAO and cilioretinal artery occlusion (CLRAO), and the latter further consists of 3 distinct clinical entities - non-arteritic CLRAO alone, non-arteritic CLRAO associated with central retinal vein occlusion and arteritic CLRAO associated with GCA. Understanding these classifications is essential to comprehend fully various aspects of these disorders. Central retinal artery occlusion The pathogeneses, clinical features and management of the various types of CRAO are discussed in detail. Contrary to the prevalent belief, spontaneous improvement in both visual acuity and visual fields does occur, mainly during the first 7 days. The incidence of spontaneous visual

Safety of iPhone retinal photography.

PubMed

Hong, Sheng Chiong; Wynn-Williams, Giles; Wilson, Graham

2017-04-01

With the advancement in mobile technology, smartphone retinal photography is becoming a popular practice. However, there is limited information about the safety of the latest smartphones used for retinal photography. This study aims to determine the photobiological risk of iPhone 6 and iPhone 6 plus when used in conjunction with a 20Diopter condensing lens for retinal photography. iPhone 6 and iPhone 6 plus (Apple, Cupertino, CA) were used in this study. The geometrical setup of the study was similar to the indirect ophthalmoscopy technique. The phone was set up at one end of the bench with its flash turned on at maximal brightness; a 20 Dioptre lens was placed 15 cm away from the phone. The light that passes through the lens was measured with a spectroradiometer and an illuminance probe at the other end to determine the spectral profile, spatial irradiance, radiant power emitted by the phone's flash. Trigonometric and lens formula were applied to determine the field of view and retinal surface in order to determine the weighted retinal irradiance and weighted retinal radiant exposure. Taking ocular transmission and the distribution of the beam's spatial irradiance into account, the weighted retinal irradiance is 1.40 mW/cm 2 and the weighted retinal radiant exposure is 56.25 mJ/cm 2 . The peak weighted foveal irradiance is 1.61 mW/cm 2 . Our study concluded that the photobiological risk posed by iPhone 6 indirect ophthalmoscopy was at least 1 order of magnitude below the safety limits set by the ISO15004-2.2.

Minireview: Fibronectin in retinal disease.

PubMed

Miller, Charles G; Budoff, Greg; Prenner, Jonathan L; Schwarzbauer, Jean E

2017-01-01

Retinal fibrosis, characterized by dysregulation of extracellular matrix (ECM) protein deposition by retinal endothelial cells, pigment epithelial cells, and other resident cell-types, is a unifying feature of several common retinal diseases. Fibronectin is an early constituent of newly deposited ECM and serves as a template for assembly of other ECM proteins, including collagens. Under physiologic conditions, fibronectin is found in all layers of Bruch's membrane. Proliferative vitreoretinopathy (PVR), a complication of retinal surgery, is characterized by ECM accumulation. Among the earliest histologic manifestations of diabetic retinopathy (DR) is capillary basement membrane thickening, which occurs due to perturbations in ECM homeostasis. Neovascularization, the hallmark of late stage DR as well as exudative age-related macular degeneration (AMD), involves ECM assembly as a scaffold for the aberrant new vessel architecture. Rodent models of retinal injury demonstrate a key role for fibronectin in complications characteristic of PVR, including retinal detachment. In mouse models of DR, reducing fibronectin gene expression has been shown to arrest the accumulation of ECM in the capillary basement membrane. Alterations in matrix metalloproteinase activity thought to be important in the pathogenesis of AMD impact the turnover of fibronectin matrix as well as collagens. Growth factors involved in PVR, AMD, and DR, such as PDGF and TGFβ, are known to stimulate fibronectin matrix assembly. A deeper understanding of how pathologic ECM deposition contributes to disease progression may help to identify novel targets for therapeutic intervention. © 2016 by the Society for Experimental Biology and Medicine.

Clinical Outcome of Retinal Vasculitis and Predictors for Prognosis of Ischemic Retinal Vasculitis.

PubMed

Sharief, Lazha; Lightman, Sue; Blum-Hareuveni, Tamar; Bar, Asaf; Tomkins-Netzer, Oren

2017-05-01

To determine factors affecting the visual outcome in eyes with retinal vasculitis and the rate of neovascularization relapse in ischemic vasculitis. Retrospective cohort study. We reviewed 1169 uveitis patients from Moorfields Eye Hospital, London, UK. Retinal vasculitis was observed in 236 eyes (121 ischemic, 115 nonischemic) that were compared with a control group (1022 eyes) with no retinal vasculitis. Ultra-widefield fluorescein angiography images were obtained in 63 eyes with ischemic vasculitis to quantify area of nonperfusion measured as ischemic index. The risk of vision loss was significantly more in the retinal vasculitis compared with the non-vasculitis group (hazard ratio [HR] 1.67, 95% confidence interval [CI] 1.24-2.25, P = .001). Retinal vasculitis had twice the risk of macular edema compared to the non-vasculitis group. Macular ischemia increased the risk of vision loss in vasculitis eyes by 4.4 times. The use of systemic prednisolone in eyes with vasculitis was associated with a reduced risk of vision loss (HR 0.36, 95% CI 0.15-0.82, P = .01). Laser photocoagulation was administered in 75 eyes (62.0%), out of which 29 (38.1%) had new vessel relapse and required additional laser treatment. The median ischemic index was 25.8% (interquartile range 10.2%-46%). Ischemia involving ≥2 quadrants was associated with increased risk of new vessel formation (HR 2.7, 95% CI 1.3-5.5, P = .003). Retinal vasculitis is associated with an increased risk of vision loss, mainly secondary to macular ischemia, and has a higher risk of macular edema compared to eyes with no vasculitis. Ischemia involving ≥2 quadrants is a risk factor for new vessel formation. Copyright © 2017 Elsevier Inc. All rights reserved.

Reprogramming retinal neurons and standardized quantification of their differentiation in 3-dimensional retinal cultures

PubMed Central

Hiler, Daniel J.; Barabas, Marie E.; Griffiths, Lyra M.; Dyer, Michael A.

2017-01-01

Postmitotic differentiated neurons are among the most difficult cells to reprogram into induced pluripotent stem cells (iPSCs) because they have poor viability when cultured as dissociated cells. Other protocols to reprogram postmitotic neurons have required the inactivation of the p53 tumor suppressor. We describe a method that does not require p53 inactivation and induces reprogramming in cells purified from the retinae of reprogrammable mice in aggregates with wild-type retinal cells. After the first 10 days of reprogramming, the aggregates are then dispersed and plated on irradiated feeder cells to propagate and isolate individual iPSC clones. The reprogramming efficiency of different neuronal populations at any stage of development can be quantitated using this protocol. Reprogramming retinal neurons with this protocol will take 56 days, and these retina-derived iPSCs can undergo retinal differentiation to produce retinae in 34 days. In addition, we describe a quantitative assessment of retinal differentiation from these neuron-derived iPSCs called STEM-RET. The procedure quantitates eye field specification, optic cup formation, and retinal differentiation in 3-dimensional cultures using molecular, cellular and morphological criteria. An advanced level of cell culture experience is required to carry out this protocol. PMID:27658012

Doppler optical coherence tomography of retinal circulation.

PubMed

Tan, Ou; Wang, Yimin; Konduru, Ranjith K; Zhang, Xinbo; Sadda, SriniVas R; Huang, David

2012-09-18

Noncontact retinal blood flow measurements are performed with a Fourier domain optical coherence tomography (OCT) system using a circumpapillary double circular scan (CDCS) that scans around the optic nerve head at 3.40 mm and 3.75 mm diameters. The double concentric circles are performed 6 times consecutively over 2 sec. The CDCS scan is saved with Doppler shift information from which flow can be calculated. The standard clinical protocol calls for 3 CDCS scans made with the OCT beam passing through the superonasal edge of the pupil and 3 CDCS scan through the inferonal pupil. This double-angle protocol ensures that acceptable Doppler angle is obtained on each retinal branch vessel in at least 1 scan. The CDCS scan data, a 3-dimensional volumetric OCT scan of the optic disc scan, and a color photograph of the optic disc are used together to obtain retinal blood flow measurement on an eye. We have developed a blood flow measurement software called "Doppler optical coherence tomography of retinal circulation" (DOCTORC). This semi-automated software is used to measure total retinal blood flow, vessel cross section area, and average blood velocity. The flow of each vessel is calculated from the Doppler shift in the vessel cross-sectional area and the Doppler angle between the vessel and the OCT beam. Total retinal blood flow measurement is summed from the veins around the optic disc. The results obtained at our Doppler OCT reading center showed good reproducibility between graders and methods (<10%). Total retinal blood flow could be useful in the management of glaucoma, other retinal diseases, and retinal diseases. In glaucoma patients, OCT retinal blood flow measurement was highly correlated with visual field loss (R(2)>0.57 with visual field pattern deviation). Doppler OCT is a new method to perform rapid, noncontact, and repeatable measurement of total retinal blood flow using widely available Fourier-domain OCT instrumentation. This new technology may improve the

A randomized trial comparing the efficacy and safety of intravitreal triamcinolone with standard care to treat vision loss associated with macular Edema secondary to branch retinal vein occlusion: the Standard Care vs Corticosteroid for Retinal Vein Occlusion (SCORE) study report 6.

PubMed

Scott, Ingrid U; Ip, Michael S; VanVeldhuisen, Paul C; Oden, Neal L; Blodi, Barbara A; Fisher, Marian; Chan, Clement K; Gonzalez, Victor H; Singerman, Lawrence J; Tolentino, Michael

2009-09-01

To compare the efficacy and safety of 1-mg and 4-mg doses of preservative-free intravitreal triamcinolone with standard care (grid photocoagulation in eyes without dense macular hemorrhage and deferral of photocoagulation until hemorrhage clears in eyes with dense macular hemorrhage) for eyes with vision loss associated with macular edema secondary to branch retinal vein occlusion (BRVO). Multicenter, randomized clinical trial of 411 participants. Main Outcome Measure Gain in visual acuity letter score of 15 or more from baseline to month 12. Twenty-nine percent, 26%, and 27% of participants achieved the primary outcome in the standard care, 1-mg, and 4-mg groups, respectively. None of the pairwise comparisons between the 3 groups was statistically significant at month 12. The rates of elevated intraocular pressure and cataract were similar for the standard care and 1-mg groups, but higher in the 4-mg group. There was no difference identified in visual acuity at 12 months for the standard care group compared with the triamcinolone groups; however, rates of adverse events (particularly elevated intraocular pressure and cataract) were highest in the 4-mg group. Application to Clinical Practice Grid photocoagulation as applied in the SCORE Study remains the standard care for patients with vision loss associated with macular edema secondary to BRVO who have characteristics similar to participants in the SCORE-BRVO trial. Grid photocoagulation should remain the benchmark against which other treatments are compared in clinical trials for eyes with vision loss associated with macular edema secondary to BRVO. Trial Registration clinicaltrials.gov Identifier: NCT00105027.

Automated detection of retinal disease.

PubMed

Helmchen, Lorens A; Lehmann, Harold P; Abràmoff, Michael D

2014-11-01

Nearly 4 in 10 Americans with diabetes currently fail to undergo recommended annual retinal exams, resulting in tens of thousands of cases of blindness that could have been prevented. Advances in automated retinal disease detection could greatly reduce the burden of labor-intensive dilated retinal examinations by ophthalmologists and optometrists and deliver diagnostic services at lower cost. As the current availability of ophthalmologists and optometrists is inadequate to screen all patients at risk every year, automated screening systems deployed in primary care settings and even in patients' homes could fill the current gap in supply. Expanding screens to all patients at risk by switching to automated detection systems would in turn yield significantly higher rates of detecting and treating diabetic retinopathy per dilated retinal examination. Fewer diabetic patients would develop complications such as blindness, while ophthalmologists could focus on more complex cases.

Current perspectives of herpesviral retinitis and choroiditis.

PubMed

Madhavan, H N; Priya, K; Biswas, J

2004-10-01

Vision-threatening viral retinitis are primarily caused by members of the herpesvirus family. The biology and molecular characterization of herpesviruses, clinical presentations of retinopathies, pathology and pathogenesis including the host responses, epidemiology and the laboratory methods of aetiological diagnosis of these diseases are described. Clinical syndromes are acute retinal necrosis (ARN), progressive outer retinal necrosis (PORN), cytomegalovirus (CMV) retinitis, multifocal choroiditis and serpiginous choroiditis besides other viral retinopathies. Herpes simplex virus (HSV) retinitis is more common in immunocompetent persons while varicella zoster virus (VZV) affects both immunocompetent and immunosuppressed patients equally. CMV retinitis is most common among patients with AIDS. The currently employed laboratory methods of antigen detection, virus isolation and antibody detection by enzyme linked immuno-sorbent assay (ELISA) have low sensitivity. Polymerase chain reaction (PCR) has increased the value of diagnosis due to its high clinical sensitivity and absolute specificity in detection of herpesviruses in intraocular specimens.

Telemedicine diagnosis of cytomegalovirus retinitis by nonophthalmologists.

PubMed

Yen, Michael; Ausayakhun, Somsanguan; Chen, Jenny; Ausayakhun, Sakarin; Jirawison, Choeng; Heiden, David; Holland, Gary N; Margolis, Todd P; Keenan, Jeremy D

2014-09-01

Cytomegalovirus (CMV) retinitis continues to be a leading cause of blindness in many developing countries. Telemedicine holds the potential to increase the number of people screened for CMV retinitis, but it is unclear whether nonophthalmologists could be responsible for interpreting fundus photographs captured in a telemedicine program. To determine the accuracy of nonophthalmologist photographic graders in diagnosing CMV retinitis from digital fundus photographs. Fifteen nonexpert graders each evaluated 182 mosaic retinal images taken from the eyes of patients with AIDS who were evaluated at the Ocular Infectious Diseases Clinic at Chiang Mai University in Chiang Mai, Thailand. Graders diagnosed each image as CMV retinitis present, CMV retinitis absent, or unknown. The results from each grader were compared with those of an indirect ophthalmoscopic examination from an experienced on-site ophthalmologist as well as with the consensus grade given by a panel of CMV retinitis experts. Relative to the on-site ophthalmologist, the sensitivity of remote CMV retinitis diagnosis by nonexpert graders ranged from 64.0% to 95.5% (mean, 84.1%; 95% CI, 78.6%-89.6%)), and the specificity ranged from 65.6% to 92.5% (mean, 82.3%; 95% CI, 76.6%-88.0%)). Agreement between nonexpert and expert graders was high: the mean sensitivity and specificity values of nonexpert diagnosis using expert consensus as the reference standard were 93.2% (95% CI, 90.6%-95.8%) and 88.4% (95% CI, 85.4%-91.1%), respectively. Mean intrarater reliability also was high (mean Cohen κ, 0.83; 95% CI, 0.78-0.87). The sensitivity and specificity of remote diagnosis of CMV retinitis by nonexpert graders was variable, although several nonexperts achieved a level of accuracy comparable to that of CMV retinitis experts. More intensive training and periodic evaluations would be required if nonexperts are to be used in clinical practice.

Paediatric retinal detachment: aetiology, characteristics and outcomes.

PubMed

McElnea, Elizabeth; Stephenson, Kirk; Gilmore, Sarah; O'Keefe, Michael; Keegan, David

2018-01-01

To provide contemporary data on the aetiology, clinical features and outcomes of paediatric retinal detachment. A retrospective review of all those under 16y who underwent surgical repair for retinal detachment at a single centre between the years 2008 and 2015 inclusive was performed. In each case the cause of retinal detachment, the type of detachment, the presence or absence of macular involvement, the number and form of reparative surgeries undertaken, and the surgical outcome achieved was recorded. Twenty-eight eyes of 24 patients, 15 (62.5%) of whom were male and 9 (37.5%) of whom were female, their mean age being 11.6y and range 2-16y developed retinal detachment over the eight year period studied. Trauma featured in the development of retinal detachment in 14 (50.0%) cases. Retinal detachment was associated with other ocular and/or systemic conditions in 11 (39.3%) cases. A mean of 3.0 procedures with a range of 1-9 procedures per patient were undertaken in the management of retinal detachment. Complex vitrectomy combined with scleral buckling or complex vitrectomy alone were those most frequently performed. Mean postoperative visual acuity was 1.2 logMAR with range 0.0-3.0 logMAR. In 22 of 26 (84.6%) cases which underwent surgical repair the retina was attached at last follow-up. Aggressive management of paediatric retinal detachment including re-operation increases the likelihood of anatomical success. In cases where the retinal detachment can be repaired by an external approach alone there is a more favourable visual outcome.

Retrobulbar optic neuritis and rhegmatogenous retinal detachment in a fourteen-year-old girl with retinitis pigmentosa sine pigmento.

PubMed

Hatta, M; Hayasaka, S; Kato, T; Kadoi, C

2000-01-01

A 14-year-old girl complained of a sudden decrease in right visual acuity. The patient had night blindness, a mottled retina but no pigments, extinguished scotopic electroretinographic response, central scotoma in the right eye and rhegmatogenous retinal detachment. She had initially received laser photocoagulation around the retinal tear and then corticosteroid therapy, cryoretinopexy and segmental buckling. Her right visual acuity increased to 1.0. The association of retinitis pigmentosa sine pigmento, retrobulbar optic neuritis and rhegmatogenous retinal detachment, as demonstrated in our patient, may be uncommon. Copyright 2000 S. Karger AG, Basel

Imaging of retinal and choroidal vascular tumours

PubMed Central

Heimann, H; Jmor, F; Damato, B

2013-01-01

The most common intraocular vascular tumours are choroidal haemangiomas, vasoproliferative tumours, and retinal haemangioblastomas. Rarer conditions include cavernous retinal angioma and arteriovenous malformations. Options for ablating the tumour include photodynamic therapy, argon laser photocoagulation, trans-scleral diathermy, cryotherapy, anti-angiogenic agents, plaque radiotherapy, and proton beam radiotherapy. Secondary effects are common and include retinal exudates, macular oedema, epiretinal membranes, retinal fibrosis, as well as serous and tractional retinal detachment, which are treated using standard methods (ie, intravitreal anti-angiogenic agents or steroids as well as vitreoretinal procedures, such as epiretinal membrane peeling and release of retinal traction). The detection, diagnosis, and monitoring of vascular tumours and their complications have improved considerably thanks to advances in imaging. These include spectral domain and enhanced depth imaging optical coherence tomography (SD-OCT and EDI-OCT, respectively), wide-angle photography and angiography as well as wide-angle fundus autofluorescence. Such novel imaging has provided new diagnostic clues and has profoundly influenced therapeutic strategies so that vascular tumours and secondary effects are now treated concurrently instead of sequentially, enhancing any opportunities for conserving vision and the eye. In this review, we describe how SD-OCT, EDI-OCT, autofluorescence, wide-angle photography and wide-angle angiography have facilitated the evaluation of eyes with the more common vascular tumours, that is, choroidal haemangioma, retinal vasoproliferative tumours, and retinal haemangioblastoma. PMID:23196648

Spontaneous Massive Adrenal Hemorrhage: A Management Dilemma

PubMed Central

Agarwal, Anshuman

2015-01-01

Abstract Adrenal hemorrhage (AH) is a rare but life-threatening condition. Small focal hemorrhage may present subclinically, but massive hemorrhage may lead to rapid cardiovascular collapse and ultimately death if not diagnosed appropriately and treated quickly. Most cases reported in the literature have been treated conservatively. In an event of increasing hemorrhage during conservative management, it may be tricky to intervene surgically because of the hematoma around the gland. Here we describe a case where we managed a large spontaneous AH by a combination of angioembolization and laparoscopic adrenalectomy. PMID:27579389

Clinical applications of fundus autofluorescence in retinal disease.

PubMed

Yung, Madeline; Klufas, Michael A; Sarraf, David

2016-01-01

Fundus autofluorescence (FAF) is a non-invasive retinal imaging modality used in clinical practice to provide a density map of lipofuscin, the predominant ocular fluorophore, in the retinal pigment epithelium. Multiple commercially available imaging systems, including the fundus camera, the confocal scanning laser ophthalmoscope, and the ultra-widefield imaging device, are available to the clinician. Each offers unique advantages for evaluating various retinal diseases. The clinical applications of FAF continue to expand. It is now an essential tool for evaluating age related macular degeneration, macular dystrophies, retinitis pigmentosa, white dot syndromes, retinal drug toxicities, and various other retinal disorders. FAF may detect abnormalities beyond those detected on funduscopic exam, fluorescein angiography, or optical coherence tomography, and can be used to elucidate disease pathogenesis, form genotype-phenotype correlations, diagnose and monitor disease, and evaluate novel therapies. Given its ease of use, non-invasive nature, and value in characterizing retinal disease, FAF enjoys increasing clinical relevance. This review summarizes common ocular fluorophores, imaging modalities, and FAF findings for a wide spectrum of retinal disorders.

Suppression of HSP27 Restores Retinal Function and Protects Photoreceptors From Apoptosis in a Light-Induced Retinal Degeneration Animal Model.

PubMed

Chien, Chih-Cheng; Huang, Chi-Jung; Tien, Lu-Tai; Cheng, Yu-Che; Ke, Chia-Ying; Lee, Yih-Jing

2017-06-01

We used a light-induced retinal degeneration animal model to investigate possible roles of heat shock protein 27 (HSP27) in retinal/photoreceptor protection. Sprague-Dawley rats were used for the light-induced retinal degeneration animal model. The histology of eye sections was observed for morphologic changes in the retina. Cell apoptosis was examined in each group using the terminal deoxynucleotidyl transferase dUTP nick-end labeling assay, and electroretinography was used to evaluate retinal function. Protein and mRNA expression levels of different retinal cell markers were also detected through immunofluorescence staining, Western blotting, and real-time PCR. The thickness of the outer nuclear layer significantly decreased after 7-day light exposure. Moreover, we injected a viral vector for silencing HSP27 expression into the eyes and observed that photoreceptors were better preserved in the HSP27-suppressed (sHSP27) retina 2 weeks after injection. HSP27 suppression also reduced retinal cell apoptosis caused by light exposure. In addition, the loss of retinal function caused by light exposure was reversed on suppressing HSP27 expression. We subsequently found that the expression of the Rho gene and immunofluorescence staining of rhodopsin and arrestin (cell markers for photoreceptors) increased in sHSP27-treated retinas. HSP27 suppression did not affect the survival of ganglion and amacrine cells. Retinal cell apoptosis and functional loss were observed after 7-day light exposure. However, in the following 2 weeks after light exposure, HSP27 suppression may initiate a protective effect for retinal cells, particularly photoreceptors, from light-induced retinal degeneration.

[Retinal whitening following vitrectomy for epiretinal macular membrane].

PubMed

Uemura, A

1993-09-01

To investigate the clinical pictures of retinal whitening following epiretinal membrane dissection. I studied retrospectively the records of 18 eyes which had undergone vitrectomy. Two types of retinal whitening were observed: cotton wool-like spots within the superficial retinal layers and a linear or dendritic pattern within the deep retinal layers. The spots were mainly noted in idiopathic cases and resolved completely in a few weeks, and the pattern was observed in macular pucker cases after retinal detachment surgery and persisted for a long time after vitrectomy.

Intraventricular Hemorrhage in Moderate to Severe Congenital Heart Disease.

PubMed

Ortinau, Cynthia M; Anadkat, Jagruti S; Smyser, Christopher D; Eghtesady, Pirooz

2018-01-01

Determine the prevalence of intraventricular hemorrhage in infants with moderate to severe congenital heart disease, investigate the impact of gestational age, cardiac diagnosis, and cardiac intervention on intraventricular hemorrhage, and compare intraventricular hemorrhage rates in preterm infants with and without congenital heart disease. A single-center retrospective review. A tertiary care children's hospital. All infants admitted to St. Louis Children's Hospital from 2007 to 2012 with moderate to severe congenital heart disease requiring cardiac intervention in the first 90 days of life and all preterm infants without congenital heart disease or congenital anomalies/known genetic diagnoses admitted during the same time period. None. Cranial ultrasound data were reviewed for presence/severity of intraventricular hemorrhage. Head CT and brain MRI data were also reviewed in the congenital heart disease infants. Univariate analyses were undertaken to determine associations with intraventricular hemorrhage, and a final multivariate logistic regression model was performed. There were 339 infants with congenital heart disease who met inclusion criteria and 25.4% were born preterm. Intraventricular hemorrhage was identified on cranial ultrasound in 13.3% of infants, with the majority of intraventricular hemorrhage being low-grade (grade I/II). The incidence increased as gestational age decreased such that intraventricular hemorrhage was present in 8.7% of term infants, 19.2% of late preterm infants, 26.3% of moderately preterm infants, and 53.3% of very preterm infants. There was no difference in intraventricular hemorrhage rates between cardiac diagnoses. Additionally, the rate of intraventricular hemorrhage did not increase after cardiac intervention, with only three infants demonstrating new/worsening high-grade (grade III/IV) intraventricular hemorrhage after surgery. In a multivariate model, only gestational age at birth and African-American race were predictors

Syphilitic punctate inner retinitis in immunocompetent gay men.

PubMed

Wickremasinghe, Sanjeewa; Ling, Cecilia; Stawell, Richard; Yeoh, Jonathan; Hall, Anthony; Zamir, Ehud

2009-06-01

To describe the features of an unusual syphilitic uveitis syndrome in a cluster of homosexual patients. Retrospective case series. Five consecutive patients diagnosed with syphilitic retinitis in our Melbourne uveitis clinic over a period of 8 months. The case notes of patients diagnosed with syphilitic retinitis were reviewed and the clinical features are presented and discussed. Description of retinal findings and documentation of any associated sequelae. All patients were homosexual men. Two were human immunodeficiency virus positive. None of the patients had been previously diagnosed with syphilis, although 3 presented with systemic symptoms and signs of secondary syphilis. All patients had marked anterior uveitis and vitritis. All patients had acute retinal arteriolitis and inner retinitis, with distinctive, inner retinal and preretinal white dots. These retinal findings were remarkably similar in all patients, and resolved with little or no sequelae after standard systemic treatment for syphilis, combined with oral prednisolone. Syphilitic retinitis may be an increasingly common clinical problem, reflecting the growing incidence of syphilis among homosexual men in Australia. Our patients showed stereotypical ocular and systemic features, which are useful in differentiating this condition clinically from other types of acute posterior uveitis, such as necrotizing viral retinitis. Proprietary or commercial disclosure may be found after the references.

Astrocytes and Müller Cell Alterations During Retinal Degeneration in a Transgenic Rat Model of Retinitis Pigmentosa

PubMed Central

Fernández-Sánchez, Laura; Lax, Pedro; Campello, Laura; Pinilla, Isabel; Cuenca, Nicolás

2015-01-01

Purpose: Retinitis pigmentosa includes a group of progressive retinal degenerative diseases that affect the structure and function of photoreceptors. Secondarily to the loss of photoreceptors, there is a reduction in retinal vascularization, which seems to influence the cellular degenerative process. Retinal macroglial cells, astrocytes, and Müller cells provide support for retinal neurons and are fundamental for maintaining normal retinal function. The aim of this study was to investigate the evolution of macroglial changes during retinal degeneration in P23H rats. Methods: Homozygous P23H line-3 rats aged from P18 to 18 months were used to study the evolution of the disease, and SD rats were used as controls. Immunolabeling with antibodies against GFAP, vimentin, and transducin were used to visualize macroglial cells and cone photoreceptors. Results: In P23H rats, increased GFAP labeling in Müller cells was observed as an early indicator of retinal gliosis. At 4 and 12 months of age, the apical processes of Müller cells in P23H rats clustered in firework-like structures, which were associated with ring-like shaped areas of cone degeneration in the outer nuclear layer. These structures were not observed at 16 months of age. The number of astrocytes was higher in P23H rats than in the SD matched controls at 4 and 12 months of age, supporting the idea of astrocyte proliferation. As the disease progressed, astrocytes exhibited a deteriorated morphology and marked hypertrophy. The increase in the complexity of the astrocytic processes correlated with greater connexin 43 expression and higher density of connexin 43 immunoreactive puncta within the ganglion cell layer (GCL) of P23H vs. SD rat retinas. Conclusions: In the P23H rat model of retinitis pigmentosa, the loss of photoreceptors triggers major changes in the number and morphology of glial cells affecting the inner retina. PMID:26733810

[Viral retinitis following intravitreal triamcinolone injection].

PubMed

Zghal, I; Malek, I; Amel, C; Soumaya, O; Bouguila, H; Nacef, L

2013-09-01

Necrotizing viral retinitis is associated with infection by the Herpes family of viruses, especially herpes simplex virus (HSV), varicella zoster virus (VZV) and occasionally cytomegalovirus (CMV). When the diagnosis is suspected clinically, antiviral therapy must be instituted immediately. We report the case of a patient presenting with necrotizing viral retinitis 3 months following intravitreal injection of triamcinolone acetonide for diabetic macular edema. Fluorescein angiography demonstrated a superior temporal occlusive vasculitis. A diagnostic anterior chamber paracentesis was performed to obtain deoxyribo-nucleic acid (DNA) for a polymerase chain reaction (PCR) test for viral retinitis. PCR was positive for CMV. The patient was placed on intravenous ganciclovir. CMV retinitis is exceedingly rare in immunocompetent patients; however, it remains the most common cause of posterior uveitis in immunocompromised patients. The incidence of this entity remains unknown. Local immunosuppression, the dose and the frequency of injections may explain the occurrence of this severe retinitis. Copyright © 2013. Published by Elsevier Masson SAS.

[Indications for Retinal Laser Therapy Revisited].

PubMed

Enders, P; Schaub, F; Fauser, S

2017-02-10

Background Laser therapy is an important treatment option in retinal diseases, especially in cases of vascular involvement. Most approaches are based on coagulation of retinal structures. As there is increasing use of agents targetting vascular endothelial growth factor in the treatment of macular diseases, indications for the use of laser treatment need to be reviewed carefully, especially with respect to their significance in first line therapy. This article explains recent strategies and treatment protocols. Materials and Methods Review of current literature in PubMed as well as synopsis of relevant guidelines. Results and Conclusion Retinal laser therapy is still widely used within retinal opthalmology and covers a large spectrum of indications. Despite the success of medical approaches, retinal laser therapy remains an indispensable treatment option for proliferative diabetic retinopathy, central or peripheral vein occlusion and less frequent pathologies, such as retinopathy of prematurity or Coats's disease. Georg Thieme Verlag KG Stuttgart · New York.

Optical coherence tomography-guided retinal prosthesis design: model of degenerated retinal curvature and thickness for patient-specific devices.

PubMed

Opie, Nicholas L; Ayton, Lauren N; Apollo, Nicholas V; Ganesan, Kumaravelu; Guymer, Robyn H; Luu, Chi D

2014-06-01

Retinitis pigmentosa affects over 1.5 million people worldwide and is a leading cause of vision loss and blindness. While retinal prostheses have shown some success in restoring basic levels of vision, only generic, "one-size-fits-all" devices are currently being implanted. In this study, we used optical coherence tomography scans of the degenerated retina from 88 patients with retinitis pigmentosa to generate models of retinal thickness and curvature for the design of customized implants. We found the average retinal thickness at the fovea to be 152.9 ± 61.3 μm, increasing to a maximum retinal thickness of 250.9 ± 57.5 μm at a nasal eccentricity of 5°. These measures could be used to assist the development of custom-made penetrating electrodes to enhance and optimize epiretinal prostheses. From the retinal thickness measurements, we determined that the optimal length of penetrating electrodes to selectively stimulate retinal ganglion cell bodies and interneuron axons in the ganglion cell layer should be 30-100 μm, and to preferentially stimulate interneurons in the inner nuclear layer, electrodes should be 100-200 μm long. Electrodes greater than 200 μm long had the potential to penetrate through the retina into the choroid, which could cause devastating complications to the eye and should be avoided. The two- and three-dimensional models of retinal thickness developed in this study can be used to design patient-specific epiretinal implants that will help with safety and to optimize the efficacy of neuronal stimulation, ensuring the best functional performance of the device for patients. Copyright © 2014 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

The Risk of Major Hemorrhage with CKD

PubMed Central

Molnar, Amber O.; Bota, Sarah E.; Garg, Amit X.; Harel, Ziv; Lam, Ngan; McArthur, Eric; Nesrallah, Gihad; Perl, Jeffrey

2016-01-01

New staging systems for CKD account for both reduced eGFR and albuminuria; whether each measure associates with greater risk of hemorrhage is unclear. In this retrospective cohort study (2002–2010), we grouped 516,197 adults ≥40 years old by eGFR (≥90, 60 to <90, 45 to <60, 30 to <45, 15 to <30, or <15 ml/min per 1.73 m2) and urine albumin-to-creatinine ratio (ACR; >300, 30–300, or <30 mg/g) to examine incidence of hemorrhage. The 3-year cumulative incidence of hemorrhage increased 20-fold across declining eGFR and increasing urine ACR groupings (highest eGFR/lowest ACR: 0.5%; lowest eGFR/highest ACR: 10.1%). Urine ACR altered the association of eGFR with hemorrhage (P<0.001). In adjusted models using the highest eGFR/lowest ACR grouping as the referent, patients with eGFR=15 to <30 ml/min per 1.73 m2 had adjusted relative risks of hemorrhage of 1.9 (95% confidence interval [95% CI], 1.5 to 2.4) with the lowest ACR and 3.7 (95% CI, 3.0 to 4.5) with the highest ACR. Patients with the highest eGFR/highest ACR had an adjusted relative risk of hemorrhage of 2.3 (95% CI, 1.8 to 2.9), comparable with the risk for patients with the lowest eGFR/lowest ACR. The associations attenuated but remained significant after adjustment for anticoagulant and antiplatelet use in patients ≥66 years old. The risk of hemorrhage differed by urine ACR in high risk subgroups. Our data show that declining eGFR and increasing albuminuria each independently increase hemorrhage risk. Strategies to reduce hemorrhage events among patients with CKD are warranted. PMID:26823554

External Ventricular Drain and Hemorrhage in Aneurysmal Subarachnoid Hemorrhage Patients on Dual Antiplatelet Therapy: A Retrospective Cohort Study.

PubMed

Hudson, Joseph S; Prout, Benjamin S; Nagahama, Yasunori; Nakagawa, Daichi; Guerrero, Waldo R; Zanaty, Mario; Chalouhi, Nohra; Jabbour, Pascal; Dandapat, Sudeepta; Allan, Lauren; Ortega-Gutierrez, Santiago; Samaniego, Edgar A; Hasan, David

2018-04-11

Stenting and flow diversion for aneurysmal sub arachnoid hemorrhage (aSAH) require the use of dual antiplatelet therapy (DAPT). To investigate whether DAPT is associated with hemorrhagic complication following placement of external ventricular drains (EVD) in patients with aSAH. Rates of radiographically identified hemorrhage associated with EVD placement were compared between patients who received DAPT for stenting or flow diversion, and patients who underwent microsurgical clipping or coiling and did not receive DAPT by way of a backward stepwise multivariate analysis. Four hundred forty-three patients were admitted for aSAH management. Two hundred ninety-eight patients required placement of an EVD. One hundred twenty patients (40%) were treated with stent-assisted coiling or flow diversion and required DAPT, while 178 patients (60%) were treated with coiling without stents or microsurgical clipping and did not receive DAPT. Forty-two (14%) cases of new hemorrhage along the EVD catheter were identified radiographically. Thirty-two of these hemorrhages occurred in patients on DAPT, while 10 occurred in patients without DAPT. After multivariate analysis, DAPT was significantly associated with radiographic hemorrhage [odds ratio: 4.92, 95% confidence interval: 2.45-9.91, P = .0001]. We did not observe an increased proportion of symptomatic hemorrhage in patients receiving DAPT (10 of 32 [31%]) vs those without (5 of 10 [50%]; P = .4508). Patients with aSAH who receive stent-assisted coiling or flow diversion are at higher risk for radiographic hemorrhage associated with EVD placement. The timing between EVD placement and DAPT initiation does not appear to be of clinical significance. Stenting and flow diversion remain viable options for aSAH patients.

Treatment of hemorrhagic gastritis by antacid.

PubMed

Simonian, S J; Curtis, L E

1976-10-01

A simple and safe method of nonsurgical treatment for the control of massive acute gastric mucosal hemorrhage is described. The procedure was developed from experimental and clinical observations that the presence of gastric hydrocloric acid played an important part in the development and perpetuation of the entity. The treatment consists of complete neutralization of gastric acid with antacid to a pH of 7. The antacid is intermittently added and aspirate at 7. In a retrospective analysis, the hemorrhage was controlled in 44 of 49 patients (89%). Five patients who continued to bleed underwent surgery (10%). Three patients had vagotomy and pyloroplasty and their bleeding ceased without recurrence. Two patients underwent partial gastrectomy, but they developed recurrent bleeding and died. One patient whose bleeding has been controlled by vagotomy and pyloroplasty died without hemorrhage 10 days after operation. Of the 44 patients whose bleeding had been controlled by antacid, 11 patients died without hemorrhage one or more weeks later. These results of 89% control of hemorrhage compare favorably with those in the literature.

Treatment of hemorrhagic gastritis by antacid.

PubMed Central

Simonian, S J; Curtis, L E

1976-01-01

A simple and safe method of nonsurgical treatment for the control of massive acute gastric mucosal hemorrhage is described. The procedure was developed from experimental and clinical observations that the presence of gastric hydrocloric acid played an important part in the development and perpetuation of the entity. The treatment consists of complete neutralization of gastric acid with antacid to a pH of 7. The antacid is intermittently added and aspirate at 7. In a retrospective analysis, the hemorrhage was controlled in 44 of 49 patients (89%). Five patients who continued to bleed underwent surgery (10%). Three patients had vagotomy and pyloroplasty and their bleeding ceased without recurrence. Two patients underwent partial gastrectomy, but they developed recurrent bleeding and died. One patient whose bleeding has been controlled by vagotomy and pyloroplasty died without hemorrhage 10 days after operation. Of the 44 patients whose bleeding had been controlled by antacid, 11 patients died without hemorrhage one or more weeks later. These results of 89% control of hemorrhage compare favorably with those in the literature. PMID:13746

SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY FINDINGS IN MACULA-INVOLVING CYTOMEGALOVIRUS RETINITIS.

PubMed

Gupta, Mrinali P; Patel, Sarju; Orlin, Anton; Marlow, Elizabeth; Chee, Ru-Ik; Nadelmann, Jennifer; Chan, R V Paul; DʼAmico, Donald J; Kiss, Szilard

2018-05-01

To evaluate the microstructural features of cytomegalovirus (CMV) retinitis by spectral domain optical coherence tomography (OCT). Subjects were patients with macula-involving CMV retinitis with OCT imaging. The leading edge of retinitis in the macula was identified based on fundus imaging, and OCT findings were longitudinally evaluated in three areas: within the area of active retinitis, at the leading edge of retinitis, and just beyond the leading edge of retinitis. Optical coherence tomography imaging of macular CMV retinitis identified vitreous cells in 10 eyes (100%), posterior vitreous detachment in four eyes (40%), broad-based vitreomacular traction in one eye (10%), epiretinal membrane in eight eyes (80%), and lamellar hole-associated epiretinal proliferation associated with an atrophic hole in one eye (10%). Retinal architectural disruption, disruption of inner retinal layers, disruption of the external limiting membrane, and ellipsoid zone abnormalities were noted within the area of retinitis in all eyes and decreased in frequency and severity at and beyond the leading edge of retinitis, although all 10 eyes (100%) exhibited one of these abnormalities, especially outer retinal microabnormalities, beyond the leading edge of retinitis. Microstructural abnormalities were frequently noted on OCT of CMV retinitis, including within the retina beyond the leading edge of retinitis identified by corresponding fundus imaging. Outer retinal abnormalities were noted more frequently than inner retinal abnormalities beyond the leading edge of retinitis. These findings provide insight into the effects of CMV retinitis on retinal microstructure and potentially on vision and highlight the potential utility of OCT for monitoring microprogression of macula-involving CMV retinitis.

Retinitis pigmentosa.

PubMed

Hamel, Christian

2006-10-11

Retinitis pigmentosa (RP) is an inherited retinal dystrophy caused by the loss of photoreceptors and characterized by retinal pigment deposits visible on fundus examination. Prevalence of non syndromic RP is approximately 1/4,000. The most common form of RP is a rod-cone dystrophy, in which the first symptom is night blindness, followed by the progressive loss in the peripheral visual field in daylight, and eventually leading to blindness after several decades. Some extreme cases may have a rapid evolution over two decades or a slow progression that never leads to blindness. In some cases, the clinical presentation is a cone-rod dystrophy, in which the decrease in visual acuity predominates over the visual field loss. RP is usually non syndromic but there are also many syndromic forms, the most frequent being Usher syndrome. To date, 45 causative genes/loci have been identified in non syndromic RP (for the autosomal dominant, autosomal recessive, X-linked, and digenic forms). Clinical diagnosis is based on the presence of night blindness and peripheral visual field defects, lesions in the fundus, hypovolted electroretinogram traces, and progressive worsening of these signs. Molecular diagnosis can be made for some genes, but is not usually performed due to the tremendous genetic heterogeneity of the disease. Genetic counseling is always advised. Currently, there is no therapy that stops the evolution of the disease or restores the vision, so the visual prognosis is poor. The therapeutic approach is restricted to slowing down the degenerative process by sunlight protection and vitaminotherapy, treating the complications (cataract and macular edema), and helping patients to cope with the social and psychological impact of blindness. However, new therapeutic strategies are emerging from intensive research (gene therapy, neuroprotection, retinal prosthesis).

Retinitis pigmentosa

PubMed Central

Hamel, Christian

2006-01-01

Retinitis pigmentosa (RP) is an inherited retinal dystrophy caused by the loss of photoreceptors and characterized by retinal pigment deposits visible on fundus examination. Prevalence of non syndromic RP is approximately 1/4,000. The most common form of RP is a rod-cone dystrophy, in which the first symptom is night blindness, followed by the progressive loss in the peripheral visual field in daylight, and eventually leading to blindness after several decades. Some extreme cases may have a rapid evolution over two decades or a slow progression that never leads to blindness. In some cases, the clinical presentation is a cone-rod dystrophy, in which the decrease in visual acuity predominates over the visual field loss. RP is usually non syndromic but there are also many syndromic forms, the most frequent being Usher syndrome. To date, 45 causative genes/loci have been identified in non syndromic RP (for the autosomal dominant, autosomal recessive, X-linked, and digenic forms). Clinical diagnosis is based on the presence of night blindness and peripheral visual field defects, lesions in the fundus, hypovolted electroretinogram traces, and progressive worsening of these signs. Molecular diagnosis can be made for some genes, but is not usually performed due to the tremendous genetic heterogeneity of the disease. Genetic counseling is always advised. Currently, there is no therapy that stops the evolution of the disease or restores the vision, so the visual prognosis is poor. The therapeutic approach is restricted to slowing down the degenerative process by sunlight protection and vitaminotherapy, treating the complications (cataract and macular edema), and helping patients to cope with the social and psychological impact of blindness. However, new therapeutic strategies are emerging from intensive research (gene therapy, neuroprotection, retinal prosthesis). PMID:17032466

Visual Acuity is Related to Parafoveal Retinal Thickness in Patients with Retinitis Pigmentosa and Macular Cysts

PubMed Central

Brockhurst, Robert J.; Gaudio, Alexander R.; Berson, Eliot L.

2008-01-01

Purpose To quantify the prevalence and effect on visual acuity of macular cysts in a large cohort of patients with retinitis pigmentosa. Methods In 316 patients with typical forms of retinitis pigmentosa, we measured visual acuities with Early Treatment Diabetic Retinopathy Study (ETDRS) charts, detected macular cysts with optical coherence tomography (OCT), and quantified retinal thicknesses by OCT. We used the FREQ, LOGISTIC, and GENMOD procedures of SAS to evaluate possible risk factors for cyst prevalence and the MIXED procedure to quantify the relationships of visual acuity to retinal thickness measured at different locations within the macula. Results We found macular cysts in 28% of the patients, 40% of whom had cysts in only one eye. Macular cysts were seen most often in patients with dominant disease and not at all in patients with X-linked disease (p = 0.006). In eyes with macular cysts, multiple regression analysis revealed that visual acuity was inversely and independently related to retinal thickness at the foveal center (p = 0.038) and within a ring spanning an eccentricity of 5° to 10° from the foveal center (p = 0.004). Conclusions Macular cysts are a common occurrence in retinitis pigmentosa, especially among patients with dominantly-inherited disease. Visual acuity is influenced by edema in the parafovea, as well as in the fovea. PMID:18552390

Retinal oximetry during treatment of retinal vein occlusion by ranibizumab in patients with high blood pressure and dyslipidemia.

PubMed

Keilani, C; Halalchi, A; Wakpi Djeugue, D; Regis, A; Abada, S

2016-12-01

In the present study, we examined retinal vascular oxygen saturation in patients with retinal vein occlusion (RVO), high blood pressure (HBP) and dyslipidemia, before and during intravitreal vascular endothelial growth factor (VEGF) injection (ranibizumab). We retrospectively reviewed the medical records of six patients with visual acuity (VA) reduced by macular edema (ME) secondary to RVO with HBP and dyslipidemia, who underwent intravitreal anti-VEGF injection between October 2014 and February 2015 in the department of ophthalmology of François-Quesnay Hospital at Mantes-la-Jolie (France). The main inclusion criterion was the presence of RVO with ME and decreased VA. The primary endpoint was improvement of retinal venous oxygen saturation in patients with RVO before and 3 months after intravitreal ranibizumab injection. Secondary outcomes were improvement of retinal arterial oxygen saturation, improvement of best-corrected visual acuity (BCVA) on the Early Treatment Diabetic Retinopathy Study (ETDRS) scale, regression of ME measured by the central macular thickness (CMT) in nm and studying the correlation between blood pressure (BP) and retinal venous oxygen saturation before and after ranibizumab. Six eyes of six patients were included. Before treatment, the mean (standard deviation [SD]) of the retinal venous saturation (%) was 38.1±14.2. Three months after the injections, the mean (SD) of the retinal venous saturation (%) increased statistically significantly 49.2±11 (P=0.03). In this study, retinal venous oxygen saturation in patients with RVO, HBP and dyslipidemia was partially normalized during intravitreal ranibizumab treatment. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

New Wrinkles in Retinal Densitometry

PubMed Central

Masella, Benjamin D.; Hunter, Jennifer J.; Williams, David R.

2014-01-01

Purpose. Retinal densitometry provides objective information about retinal function. But, a number of factors, including retinal reflectance changes that are not directly related to photopigment depletion, complicate its interpretation. We explore these factors and suggest a method to minimize their impact. Methods. An adaptive optics scanning light ophthalmoscope (AOSLO) was used to measure changes in photoreceptor reflectance in monkeys before and after photopigment bleaching with 514-nm light. Reflectance measurements at 514 nm and 794 nm were recorded simultaneously. Several methods of normalization to extract the apparent optical density of the photopigment were compared. Results. We identified stimulus-related fluctuations in 794-nm reflectance that are not associated with photopigment absorptance and occur in both rods and cones. These changes had a magnitude approaching those associated directly with pigment depletion, precluding the use of infrared reflectance for normalization. We used a spatial normalization method instead, which avoided the fluctuations in the near infrared, as well as a confocal AOSLO designed to minimize light from layers other than the receptors. However, these methods produced a surprisingly low estimate of the apparent rhodopsin density (animal 1: 0.073 ± 0.006, animal 2: 0.032 ± 0.003). Conclusions. These results confirm earlier observations that changes in photopigment absorption are not the only source of retinal reflectance change during dark adaptation. It appears that the stray light that has historically reduced the apparent density of cone photopigment in retinal densitometry arises predominantly from layers near the photoreceptors themselves. Despite these complications, this method provides a valuable, objective measure of retinal function. PMID:25316726

Retinal imaging using adaptive optics technology☆

PubMed Central

Kozak, Igor

2014-01-01

Adaptive optics (AO) is a technology used to improve the performance of optical systems by reducing the effect of wave front distortions. Retinal imaging using AO aims to compensate for higher order aberrations originating from the cornea and the lens by using deformable mirror. The main application of AO retinal imaging has been to assess photoreceptor cell density, spacing, and mosaic regularity in normal and diseased eyes. Apart from photoreceptors, the retinal pigment epithelium, retinal nerve fiber layer, retinal vessel wall and lamina cribrosa can also be visualized with AO technology. Recent interest in AO technology in eye research has resulted in growing number of reports and publications utilizing this technology in both animals and humans. With the availability of first commercially available instruments we are making transformation of AO technology from a research tool to diagnostic instrument. The current challenges include imaging eyes with less than perfect optical media, formation of normative databases for acquired images such as cone mosaics, and the cost of the technology. The opportunities for AO will include more detailed diagnosis with description of some new findings in retinal diseases and glaucoma as well as expansion of AO into clinical trials which has already started. PMID:24843304

Highly efficient retinal metabolism in cones

PubMed Central

Miyazono, Sadaharu; Shimauchi-Matsukawa, Yoshie; Tachibanaki, Shuji; Kawamura, Satoru

2008-01-01

After bleaching of visual pigment in vertebrate photoreceptors, all-trans retinal is reduced to all-trans retinol by retinol dehydrogenases (RDHs). We investigated this reaction in purified carp rods and cones, and we found that the reducing activity toward all-trans retinal in the outer segment (OS) of cones is >30 times higher than that of rods. The high activity of RDHs was attributed to high content of RDH8 in cones. In the inner segment (IS) in both rods and cones, RDH8L2 and RDH13 were found to be the major enzymes among RDH family proteins. We further found a previously undescribed and effective pathway to convert 11-cis retinol to 11-cis retinal in cones: this oxidative conversion did not require NADP+ and instead was coupled with reduction of all-trans retinal to all-trans retinol. The activity was >50 times effective than the oxidizing activity of RDHs that require NADP+. These highly effective reactions of removal of all-trans retinal by RDH8 and production of 11-cis retinal by the coupling reaction are probably the underlying mechanisms that ensure effective visual pigment regeneration in cones that function under much brighter light conditions than rods. PMID:18836074

Ocular toxoplasmosis and retinal detachment: five case reports.

PubMed

Kianersi, F; Naderi Beni, A; Ghanbari, H; Fazel, F

2012-10-01

Ocular toxoplasmosis is a potentially blinding cause of posterior uveitis. Retinal detachment is rare complication of ocular toxoplasmosis. To report the clinical course and prognosis of retinal breaks and detachments occurring in patients with ocular toxoplasmosis. This study was a retrospective, non-comparative case series of five patients with ocular toxoplasmosis who had consulted us with retinal detachment. All of the participants had retinal detachment after severe and treatment resistant toxoplasmic retinochoroiditis, leaving one of them with decreased visual acuity to light perception in spite of treatment and final visual acuity was 20/100 or better in four patients. The functional prognosis for the patients with retinal detachment was poor. Careful retinal examination in ocular toxoplasmosis is warranted, especially in patients with severe intraocular inflammation.

Evaluating the Epidemiology of Inflicted Traumatic Brain Injury in Infants of U.S. Military Families

DTIC Science & Technology

2008-01-01

subdural hematoma and whiplash injuries. Caffey3 in 1972 theorized that shaking was responsible for retinal hemorrhages and subdural or subarachnoid...and contusion 852.xx Subarachnoid, subdural , and extradural hemorrhage after injury 853.xx Other and unspecified intracranial hemorrhage following

Hemorrhagic cystitis: A challenge to the urologist

PubMed Central

Manikandan, R.; Kumar, Santosh; Dorairajan, Lalgudi N.

2010-01-01

Severe hemorrhagic cystitis often arises from anticancer chemotherapy or radiotherapy for pelvic malignancies. Infectious etiologies are less common causes except in immunocompromised hosts. These cases can be challenging problems for the urologist and a source of substantial morbidity and sometimes mortality for the patients. A variety of modalities of treatment have been described for the management of hemorrhagic cystitis but there is none that is uniformly effective. Some progress has been made in the understanding and management of viral hemorrhagic cystitis. This article reviews the common causes of severe hemorrhagic cystitis and the currently available management options. PMID:20877590

A selected review of current retinal research and study.

PubMed

Cohen, J

1979-02-01

This paper presents a digest of 50 retinal research projects reported in one British and two American journals from July 1976 through June 1977. The articles reviewed report recent developments pertaining to effects of excessive light on retinal tissue in newborn rats, pathogenesis of cotton-wool spots, control of the blood-retinal barrier in diabetes, infections, macular diseases, variations in retinal pigment epithelium, and retinal detachment.

To report a case of unilateral proliferative retinopathy following noncerebral malaria with Plasmodium falciparum in Southern India.

PubMed

Verma, Aditya; Krishna, M S

2015-01-01

The retinopathy in association with malaria fever described so far includes retinal hemorrhages, vessel changes, retinal discoloration/whitening and papilledema. Malaria retinopathy has been mostly described in severe cases, associated with Plasmodium falciparum, correlating the patho-physiology of retinal and cerebral manifestations. We report an unusual case of proliferative retinopathy as a manifestation of malaria fever, caused by P. falciparum with no cerebral involvement. The patient had features of unilateral retinal vascular occlusion with proliferative changes and vitreous hemorrhage. To the best of our knowledge, such a case has never been reported so far in the literature. This report highlights the possible occurrence of severe proliferative changes associated with malaria fever, which if diagnosed early can prevent possible blindness.

Retinal detachment in pseudophakia.

PubMed

Galin, M A; Poole, T A; Obstbaum, S A

1979-07-01

In a series of cataract patients excluding myopic individuals, under age 60 years, and cases in which vitreous loss occurred, retinal detachment was no less frequent after intracapsular cataract extraction and Sputnik iris supported lenses than in controls. Both groups were followed up for a minimum of two years. The detachments predominantly occurred from retinal breaks in areas of the retina that looked normal preoperatively.

Toward high-resolution optoelectronic retinal prosthesis

NASA Astrophysics Data System (ADS)

Palanker, Daniel; Huie, Philip; Vankov, Alexander; Asher, Alon; Baccus, Steven

2005-04-01

It has been already demonstrated that electrical stimulation of retina can produce visual percepts in blind patients suffering from macular degeneration and retinitis pigmentosa. Current retinal implants provide very low resolution (just a few electrodes), while several thousand pixels are required for functional restoration of sight. We present a design of the optoelectronic retinal prosthetic system that can activate a retinal stimulating array with pixel density up to 2,500 pix/mm2 (geometrically corresponding to a visual acuity of 20/80), and allows for natural eye scanning rather than scanning with a head-mounted camera. The system operates similarly to "virtual reality" imaging devices used in military and medical applications. An image from a video camera is projected by a goggle-mounted infrared LED-LCD display onto the retina, activating an array of powered photodiodes in the retinal implant. Such a system provides a broad field of vision by allowing for natural eye scanning. The goggles are transparent to visible light, thus allowing for simultaneous utilization of remaining natural vision along with prosthetic stimulation. Optical control of the implant allows for simple adjustment of image processing algorithms and for learning. A major prerequisite for high resolution stimulation is the proximity of neural cells to the stimulation sites. This can be achieved with sub-retinal implants constructed in a manner that directs migration of retinal cells to target areas. Two basic implant geometries are described: perforated membranes and protruding electrode arrays. Possibility of the tactile neural stimulation is also examined.

Anti-epileptic Drug (AED) Use in Subarachnoid Hemorrhage (SAH) and Intracranial Hemorrhage (ICH).

PubMed

Feng, Rui; Mascitelli, Justin; Chartrain, Alexander G; Margetis, Konstantinos; Mocco, J

2017-01-01

Aneurysmal subarachnoid hemorrhage (aSAH) and spontaneous intracranial hemorrhage (ICH) are frequently associated with epileptic complications. The use of anti-epileptic drugs (AEDs) for seizure prophylaxis, however, is controversial. In patients with aSAH, nonconvulsive status epilepticus has been associated with poor outcome. Effect of other forms of less severe epileptiform activity on clinical outcome remains unclear. Evidence on efficacy of AEDs in reducing seizure incidence is also mixed. However, increasing number of studies suggest that AEDs may have significant adverse effects on outcome, especially with phenytoin. Similarly, in patients with ICH, the impact of seizures that do not progress to status epilepticus on clinical outcome is controversial, and whether prophylactic AED use has independent effects on outcome remains ambiguous. Currently, there are no large scale randomized control trials investigating the efficacy and safety of AED prophylaxis in patients with hemorrhagic stroke. There are also no trials comparing the efficacy and safety of the different AEDs. Survey based studies have found a wide range of prescribing patterns across treatment centers and clinicians for seizure prophylaxis in patients with hemorrhagic stroke. The lack of clear guidelines and recommendations also highlights the paucity of good quality evidence in this area. In conclusion, a well-designed randomized, double blinded, and appropriately powered trial is needed to evaluate the incidence as well as clinical outcomes in patients with aSAH and ICH who received AED prophylaxis versus controls. The results will be extremely valuable in providing evidence to establish management guidelines for patients with hemorrhagic stroke. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Inherited Retinal Degenerative Disease Clinical Trial Network. Addendum

DTIC Science & Technology

2010-10-01

by retinitis pigmentosa (RP) and other forms of rare inherited retinal degenerative diseases is estimated at approximately 200,000 individuals. RP... Retinitis Pigmentosa ). NNRI is awaiting final protocol review and HRPO approval for NNRI and the three enrolling clinical sites- the CTEC site at...acid) in individuals with autosomal dominant retinitis pigmentosa , with the ability to expand the enrollment to individuals with autosomal recessive

Branch retinal vein thrombosis and visual loss probably associated with pegylated interferon therapy of chronic hepatitis C

PubMed Central

Gonçalves, Luciana Lofego; Farias, Alberto Queiroz; Gonçalves, Patrícia Lofego; D’Amico, Elbio Antonio; Carrilho, Flair José

2006-01-01

Ophthalmological complications with interferon therapy are usually mild and reversible, not requiring the withdrawal of the treatment. We report a case of a patient who had visual loss probably associated with interferon therapy. Chronic hepatitis C virus infection (genotype 1a) was diagnosed in a 33-year old asymptomatic man. His past medical history was unremarkable and previous routine ophthalmologic check-up was normal. Pegylated interferon alpha and ribavirin were started. Three weeks later he reported painless reduction of vision. Ophthalmologic examination showed extensive intraretinal hemorrhages and cotton-wool spots, associated with inferior branch retinal vein thrombosis. Antiviral therapy was immediately discontinued, but one year later he persists with severely decreased visual acuity. This case illustrates the possibility of unpredictable and severe complications during pegylated interferon therapy. PMID:16874884

Acute Arthritis in Crimean-Congo Hemorrhagic Fever

PubMed Central

Ahmeti, Salih; Ajazaj-Berisha, Lindita; Halili, Bahrije; Shala, Anita

2014-01-01

Crimean-Congo hemorrhagic fever is a severe viral disease caused by a Nairovirus. An atypical manifestation in the form of acute arthritis was found in a confirmed Crimean-Congo hemorrhagic fever virus Kosova-Hoti strain positive patient. Acute arthritis in Crimean-Congo hemorrhagic fever (CCHF) may be as a result of immune mechanisms or the bleeding disorder underlying CCHF. PMID:24926169

Retinitis pigmentosa and congenital toxoplasmosis: a rare coexistence.

PubMed

Chhabra, Manpreet S; Prakash, Gunjan; Vashisht, Nagender; Garg, S P

2007-01-01

We describe a previously unreported co-existence of retinitis pigmentosa and congenital toxoplasmosis. An eight year old male presented to our center with complaints of decreased night vision. Fundus evaluations in both the eyes demonstrated features typical of retinitis pigmentosa. There were well-defined punched out healed chorio-retinal scars suggestive of congenital toxoplasmosis. On the basis of history, clinical findings and reduction of a and b wave amplitudes on scotopic and photopic electroretinograph, a diagnosis of retinitis pigmentosa with congenital toxoplasmosis was made. Retinitis pigmentosa may co-exist with congenital toxoplasmosis that may affect the patient's overall ocular morbidity and visual acuity.

Application of stem cell-derived retinal pigmented epithelium in retinal degenerative diseases: present and future.

PubMed

Luo, Mingyue; Chen, Youxin

2018-01-01

As a constituent of blood-retinal barrier and retinal outer segment (ROS) scavenger, retinal pigmented epithelium (RPE) is fundamental to normal function of retina. Malfunctioning of RPE contributes to the onset and advance of retinal degenerative diseases. Up to date, RPE replacement therapy is the only possible method to completely reverse retinal degeneration. Transplantation of human RPE stem cell-derived RPE (hRPESC-RPE) has shown some good results in animal models. With promising results in terms of safety and visual improvement, human embryonic stem cell-derived RPE (hESC-RPE) can be expected in clinical settings in the near future. Despite twists and turns, induced pluripotent stem cell-derived RPE (iPSC-RPE) is now being intensely investigated to overcome genetic and epigenetic instability. By far, only one patient has received iPSC-RPE transplant, which is a hallmark of iPSC technology development. During follow-up, no major complications such as immunogenicity or tumorigenesis have been observed. Future trials should keep focusing on the safety of stem cell-derived RPE (SC-RPE) especially in long period, and better understanding of the nature of stem cell and the molecular events in the process to generate SC-RPE is necessary to the prosperity of SC-RPE clinical application.

Reprogramming the metabolome rescues retinal degeneration.

PubMed

Park, Karen Sophia; Xu, Christine L; Cui, Xuan; Tsang, Stephen H

2018-05-01

Metabolomics studies in the context of ophthalmology have largely focused on identifying metabolite concentrations that characterize specific retinal diseases. Studies involving mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy have shown that individuals suffering from retinal diseases exhibit metabolic profiles that markedly differ from those of control individuals, supporting the notion that metabolites may serve as easily identifiable biomarkers for specific conditions. An emerging branch of metabolomics resulting from biomarker studies, however, involves the study of retinal metabolic dysfunction as causes of degeneration. Recent publications have identified a number of metabolic processes-including but not limited to glucose and oxygen metabolism-that, when perturbed, play a role in the degeneration of photoreceptor cells. As a result, such studies have led to further research elucidating methods for prolonging photoreceptor survival in an effort to halt degeneration in its early stages. This review will explore the ways in which metabolomics has deepened our understanding of the causes of retinal degeneration and discuss how metabolomics can be used to prevent retinal degeneration from progressing to its later disease stages.

Dynamics of retinal photocoagulation and rupture

NASA Astrophysics Data System (ADS)

Sramek, Christopher; Paulus, Yannis; Nomoto, Hiroyuki; Huie, Phil; Brown, Jefferson; Palanker, Daniel

2009-05-01

In laser retinal photocoagulation, short (<20 ms) pulses have been found to reduce thermal damage to the inner retina, decrease treatment time, and minimize pain. However, the safe therapeutic window (defined as the ratio of power for producing a rupture to that of mild coagulation) decreases with shorter exposures. To quantify the extent of retinal heating and maximize the therapeutic window, a computational model of millisecond retinal photocoagulation and rupture was developed. Optical attenuation of 532-nm laser light in ocular tissues was measured, including retinal pigment epithelial (RPE) pigmentation and cell-size variability. Threshold powers for vaporization and RPE damage were measured with pulse durations ranging from 1 to 200 ms. A finite element model of retinal heating inferred that vaporization (rupture) takes place at 180-190°C. RPE damage was accurately described by the Arrhenius model with activation energy of 340 kJ/mol. Computed photocoagulation lesion width increased logarithmically with pulse duration, in agreement with histological findings. The model will allow for the optimization of beam parameters to increase the width of the therapeutic window for short exposures.

Obstetric Emergencies: Shoulder Dystocia and Postpartum Hemorrhage.

PubMed

Dahlke, Joshua D; Bhalwal, Asha; Chauhan, Suneet P

2017-06-01

Shoulder dystocia and postpartum hemorrhage represent two of the most common emergencies faced in obstetric clinical practice, both requiring prompt recognition and management to avoid significant morbidity or mortality. Shoulder dystocia is an uncommon, unpredictable, and unpreventable obstetric emergency and can be managed with appropriate intervention. Postpartum hemorrhage occurs more commonly and carries significant risk of maternal morbidity. Institutional protocols and algorithms for the prevention and management of shoulder dystocia and postpartum hemorrhage have become mainstays for clinicians. The goal of this review is to summarize the diagnosis, incidence, risk factors, and management of shoulder dystocia and postpartum hemorrhage. Copyright © 2017 Elsevier Inc. All rights reserved.

Assessment of Murine Retinal Function by Electroretinography

PubMed Central

Benchorin, Gillie; Calton, Melissa A.; Beaulieu, Marielle O.; Vollrath, Douglas

2017-01-01

The electroretinogram (ERG) is a sensitive and noninvasive method for testing retinal function. In this protocol, we describe a method for performing ERGs in mice. Contact lenses on the mouse cornea measure the electrical response to a light stimulus of photoreceptors and downstream retinal cells, and the collected data are analyzed to evaluate retinal function. PMID:29177186

Regulation of human retinal blood flow by endothelin-1.

PubMed

Polak, Kaija; Luksch, Alexandra; Frank, Barbara; Jandrasits, Kerstin; Polska, Elzbieta; Schmetterer, Leopold

2003-05-01

There is evidence from in vitro and animal studies that endothelin is a major regulator of retinal blood flow. We set out to characterize the role of the endothelin-system in the blood flow control of the human retina. Two studies in healthy subjects were performed. The study design was randomized, placebo-controlled, double-masked, balanced, two-way crossover in protocol A and three way-way crossover in protocol B. In protocol A 18 healthy male subjects received intravenous endothelin-1 (ET-1) in a dose of 2.5 ng kg (-1)min(-1) for 30 min or placebo on two different study days and retinal vessel diameters were measured. In protocol B 12 healthy male subjects received ET-1 in stepwise increasing doses of 0, 1.25, 2.5 and 5 ng kg (-1)min(-1) (each infusion step over 20 min) in co-infusion with the specific ET(A)-receptor antagonist BQ123 (60 microg min (-1)) or placebo or BQ123 alone investigating retinal vessel diameters, retinal blood velocity and retinal blood flow. Measurements of retinal vessel size were done with the Zeiss retinal vessel analyzer. Measurements of blood velocities were done with bi-directional laser Doppler velocimetry. From these measurements retinal blood flow was calculated. In protocol A exogenous ET-1 tended to decrease retinal arterial diameter, but this effect was not significant versus placebo. No effect on retinal venous diameter was seen. In protocol B retinal venous blood velocity and retinal blood flow was significantly reduced after administration of exogenous ET-1. These effects were significantly blunted when BQ-123 was co-administered. By contrast, BQ-123 alone had no effect on retinal hemodynamic parameters. Concluding, BQ123 antagonizes the effects of exogenously administered ET-1 on retinal blood flow in healthy subjects. In addition, the results of the present study are compatible with the hypothesis that ET-1 exerts its vasoconstrictor effects in the retina mainly on the microvessels.

[Gene therapy for inherited retinal dystrophies].

PubMed

Côco, Monique; Han, Sang Won; Sallum, Juliana Maria Ferraz

2009-01-01

The inherited retinal dystrophies comprise a large number of disorders characterized by a slow and progressive retinal degeneration. They are the result of mutations in genes that express in either the photoreceptor cells or the retinal pigment epithelium. The mode of inheritance can be autosomal dominant, autosomal recessive, X linked recessive, digenic or mitochondrial DNA inherited. At the moment, there is no treatment for these conditions and the patients can expect a progressive loss of vision. Accurate genetic counseling and support for rehabilitation are indicated. Research into the molecular and genetic basis of disease is continually expanding and improving the prospects for rational treatments. In this way, gene therapy, defined as the introduction of exogenous genetic material into human cells for therapeutic purposes, may ultimately offer the greatest treatment for the inherited retinal dystrophies. The eye is an attractive target for gene therapy because of its accessibility, immune privilege and translucent media. A number of retinal diseases affecting the eye have known gene defects. Besides, there is a well characterized animal model for many of these conditions. Proposals for clinical trials of gene therapy for inherited retinal degenerations owing to defects in the gene RPE65, have recently received ethical approval and the obtained preliminary results brought large prospects in the improvement on patient's quality of life.

Retinal phlebitis associated with autoimmune hemolytic anemia.

PubMed

Chew, Fiona L M; Tajunisah, Iqbal

2009-01-01

To describe a case of retinal phlebitis associated with autoimmune hemolytic anemia. Observational case report. A 44-year-old Indian man diagnosed with autoimmune hemolytic anemia presented with a 1-week history of blurred vision in both eyes. Fundus biomicroscopy revealed bilateral peripheral retinal venous sheathing and cellophane maculopathy. Fundus fluorescent angiogram showed bilateral late leakage from the peripheral venous arcades and submacular fluid accumulation. The retinal phlebitis resolved following a blood transfusion and administration of systemic steroids. Retinopathy associated with autoimmune hemolytic anemia is not well known. This is thought to be the first documentation of retinal phlebitis occurring in this condition.

Retinal astrocytoma in a dog.

PubMed

Kuroki, Keiichi; Kice, Nathan; Ota-Kuroki, Juri

2017-09-01

A miniature schnauzer dog presenting with hyphema and glaucoma of the right eye had a retinal neoplasm. Neoplastic cells stained positively for glial fibrillary acidic protein, vimentin, and S-100 and largely negatively for oligodendrocyte transcription factor 2 by immunohistochemistry. The clinical and histopathological features of canine retinal astrocytomas are discussed.

Perceptual Fading without Retinal Adaptation

ERIC Educational Resources Information Center

Hsieh, Po-Jang; Colas, Jaron T.

2012-01-01

A retinally stabilized object readily undergoes perceptual fading and disappears from consciousness. This startling phenomenon is commonly believed to arise from local bottom-up sensory adaptation to edge information that occurs early in the visual pathway, such as in the lateral geniculate nucleus of the thalamus or retinal ganglion cells. Here…

[To cognize retinitis pigmentosa with scientific view].

PubMed

Li, Gen-lin

2009-03-01

Retinitis pigmentosa (RP) is the most common inherited eye disease that usually leads into blind, and is high simplex and clinical heterogeneity. Recent years, some new hereditary forms have been found, such as digenic RP, mitochondrial RP, incomplete dominant inheritance RP. The phenotype of RP is multiplicity. Incompatible phenomenon between genotype and phenotypes was shown in some genes such as peripherin/RDS, RHO, RP2 and RP3. The complicated phenotype was shown in the rare RP forms, such as centricity RP, stemma RP, retinitis pigmentosa sine pigmento, and retinal degeneration slow. Retinal transplantation, retinal implantation, drug and neurotrophic factor therapy, and gene therapy have been well studied worldwide and presented some hopeful efficacy. Ophthalmologists and practitioners should cognize the new advance and new knowledge on RP therapy with a scientific view for better serving the RP patients.

Retinal detachment caused by Arruga suture scleral intrusion. Treatment.

PubMed

Sánchez-Vicente, J L; Rueda-Rueda, T; González-García, M L; López-Herrero, F; Sánchez-Vicente, P; Castilla-Lázpita, A

2015-10-01

We present the case of an 81-year-old man with retinal detachment caused by intrusion of an Arruga suture. The encircling buckle was located in the sub-retinal space and caused retinal breaks with retinal detachment A pars plana vitrectomy was performed along with intraocular cutting of the Arruga suture with retinal re-attachment. Copyright © 2014 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

Hemorrhage and Hemorrhagic Shock in Swine: A Review

DTIC Science & Technology

1989-11-01

17 Temperature Regulation ....................... 18 Blood Gas and Acid- Base Status ....................... 18 Electrolyte...22 Renal Function .................................. 23 Hepatic Function ................................ 24 Central Nervous System Function...MODELS Most porcine hemorrhage models are based on concepts and procedures previously developed in other species, especially the dog. As a consequence

Progressive Chronic Retinal Axonal Loss Following Acute Methanol-Induced Optic Neuropathy: Four-Year Prospective Cohort Study.

PubMed

Nurieva, Olga; Diblik, Pavel; Kuthan, Pavel; Sklenka, Petr; Meliska, Martin; Bydzovsky, Jan; Heissigerova, Jarmila; Urban, Pavel; Kotikova, Katerina; Navratil, Tomas; Komarc, Martin; Seidl, Zdenek; Vaneckova, Manuela; Pelclova, Daniela; Zakharov, Sergey

2018-04-27

To study the dynamics and clinical determinants of chronic retinal nerve fiber layer thickness (RNFL) loss after methanol-induced optic neuropathy. Prospective cohort study. All patients underwent complete ophthalmic evaluation including SD-OCT three times during four years of observation:4.9[±0.6], 25.0[±0.6], and 49.9[±0.5] months after discharge. Eighty-four eyes of 42 survivors of methanol poisoning; mean age (standard deviation) of 45.7[±4.4] years, and 82 eyes of 41 controls; mean age 44.0[±4.2] years. global and temporal RNFL loss. Abnormal RNFL thickness was registered in 13/42(31%) survivors of methanol poisoning and chronic axonal loss in 10/42(24%) patients. Significant decrease of global/temporal RNFL thickness during the observation period was found in the study population compared to the controls (p<0.001). The risk estimate of chronic global RNFL loss for arterial blood pH<7.3 at admission was: 11.65(1.91-71.12;95%CI) after adjusting for age and sex. The patients with chronic axonal degeneration demonstrated progressive visual loss in 7/10 cases. The patients with abnormal RNFL thickness had magnetic resonance signs of brain damage in 10/13 versus 8/29 cases with normal RNFL thickness (p=0.003). Signs of brain hemorrhages were present in 7/13 patients with abnormal RNFL thickness versus 5/29 cases with normal RNFL thickness (p=0.015). Methanol-induced optic neuropathy may lead to chronic retinal axonal loss during the following years. Arterial blood pH on admission is the strongest predictor of chronic RNFL thickness decrease. Chronic retinal neurodegeneration is associated with the progressive loss of visual functions and necrotic brain lesions. Copyright © 2018. Published by Elsevier Inc.

Wavelength dependence of laser-induced retinal injury

NASA Astrophysics Data System (ADS)

Lund, David J.; Edsall, Peter; Stuck, Bruce E.

2005-04-01

The threshold for laser-induced retinal damage is dependent primarily upon the laser wavelength and the exposure duration. The study of the wavelength dependence of the retinal damage threshold has been greatly enhanced by the availability of tunable lasers. The Optical Parametric Oscillator (OPO), capable of providing useful pulse energy throughout a tuning range from 400 nm to 2200 nm, made it possible to determine the wavelength dependence of laser-induced retinal damage thresholds for q-switched pulses throughout the visible and NIR spectrum. Studies using the a tunable TI:Saph laser and several fixed-wavelength lasers yielded threshold values for 0.1 s exposures from 440 nm to 1060 nm. Laser-induced retinal damage for these exposure durations results from thermal conversion of the incident laser irradiation and an action spectrum for thermal retinal damage was developed based on the wavelength dependent transmission and absorption of ocular tissue and chromatic aberration of the eye optics. Long (1-1000s) duration exposures to visible laser demonstrated the existence of non-thermal laser-induced retinal damage mechanisms having a different action spectrum. This paper will present the available data for the wavelength dependence of laser-induced thermal retinal damage and compare this data to the maximum permissible exposure levels (MPEs) provided by the current guidelines for the safe use of lasers.

Multifocal retinitis in New Zealand sheep dogs.

PubMed

Hughes, P L; Dubielzig, R R; Kazacos, K R

1987-01-01

Thirty-nine percent of 1,448 working sheep dogs were affected with varying degrees of multifocal retinal disease on ophthalmoscopic examination. Lesions consisted of localized areas of hyperreflexia in the tapetal fundus, often associated with hyperpigmentation. Severely affected animals had widespread hyperreflexia with retinal vascular attenuation. Only 6% of 125 New Zealand dogs raised in urban environment were similarly affected. Both eyes of 70 dogs from New Zealand were examined histologically. Forty-seven of 70 dogs had ocular inflammatory disease. Ten other dogs had noninflammatory eye disease, and 13 dogs had normal eyes. Histologically, eyes with inflammatory disease were divided into three categories: Dogs 3 years of age or less with active inflammatory disease of the retina, uvea, and vitreous. Four dogs in this group had migrating nematode larvae identified morphologically as genus Toxocara. Diffuse retinitis and retinal atrophy in conjunction with localized retinal necrosis and choroidal fibrosis. Dogs in this category were severely, clinically affected. Chronic, low-grade retinitis with variable retinal atrophy. Most dogs in this category were over 3 years of age, and many were visually functional. The existence of a definable spectrum of morphological changes associated with inflammation, suggests that Toxocara sp. ocular larva migrans may be the cause of a highly prevalent, potentially blinding syndrome of working sheep dogs in New Zealand.

Retinitis pigmentosa, pigmentary retinopathies, and neurologic diseases.

PubMed

Bhatti, M Tariq

2006-09-01

Retinitis pigmentosa (RP) refers to a group of inherited retinal diseases with phenotypic and genetic heterogeneity. The pathophysiologic basis of the progressive visual loss in patients with RP is not completely understood but is felt to be due to a primary retinal photoreceptor cell degenerative process mainly affecting the rods of the peripheral retina. In most cases RP is seen in isolation (nonsyndromic), but in some other cases it may be a part of a genetic, metabolic, or neurologic syndrome or disorder. Nyctalopia, or night blindness, is the most common symptom of RP. The classic fundus appearance of RP includes retinal pigment epithelial cell changes resulting in retinal hypo- or hyperpigmentation ("salt-and-pepper"), retinal granularity, and bone spicule formation. The retinal vessels are often narrowed or attenuated and there is a waxy pallor appearance of the optic nerve head. Electroretinography will demonstrate rod and cone photoreceptor cell dysfunction and is a helpful test in the diagnosis and monitoring of patients with RP. A detailed history with pedigree analysis, a complete ocular examination, and the appropriate paraclinical testing should be performed in patients complaining of visual difficulties at night or in dim light. This review discusses the clinical manifestations of RP as well as describing the various systemic diseases, with a special emphasis on neurologic diseases, associated with a pigmentary retinopathy.

Astaxanthin Protects Against Retinal Damage: Evidence from In Vivo and In Vitro Retinal Ischemia and Reperfusion Models.

PubMed

Otsuka, Tomohiro; Shimazawa, Masamitsu; Inoue, Yuki; Nakano, Yusuke; Ojino, Kazuki; Izawa, Hiroshi; Tsuruma, Kazuhiro; Ishibashi, Takashi; Hara, Hideaki

2016-11-01

Astaxanthin exhibits various pharmacological activities, including anti-oxidative, anti-tumor, and anti-inflammatory effects, and is thought to exert a neuroprotective effect via these mechanisms. The purpose of this study was to investigate the protective effects of astaxanthin on neuronal cell death using a retinal ischemia/reperfusion model. In vivo, retinal ischemia was induced by 5 h unilateral ligation of the pterygopalatine artery (PPA) and the external carotid artery (ECA) in ddY mice. Astaxanthin (100 mg/kg) was administered orally 1 h before induction of ischemia, immediately after reperfusion, at 6 or 12 h after reperfusion, and twice daily for the following 4 days. Histological analysis and an electroretinogram (ERG) were performed 5 days after ischemia/reperfusion. In vitro, cell death was induced in the RGC-5 (retinal precursor cells) by oxygen-glucose deprivation (OGD), and the rates of cell death and production of intracellular reactive oxygen species (ROS) were measured using nuclear staining and a ROS reactive reagent, CM-H 2 DCFDA. Histological studies revealed that astaxanthin significantly reduced retinal ischemic damage and ERG reduction. In in vitro studies, astaxanthin inhibited cell death and ROS production in a concentration-dependent manner. Collectively, these results indicate that astaxanthin inhibits ischemia-induced retinal cell death via its antioxidant effect. Hence, astaxanthin might be effective in treating retinal ischemic pathologies.

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

PubMed

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

1990-08-01

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

Retinal pigment epithelium culture;a potential source of retinal stem cells.

PubMed

Akrami, Hassan; Soheili, Zahra-Soheila; Khalooghi, Keynoush; Ahmadieh, Hamid; Rezaie-Kanavi, Mojgan; Samiei, Shahram; Davari, Malihe; Ghaderi, Shima; Sanie-Jahromi, Fatemeh

2009-07-01

To establish human retinal pigment epithelial (RPE) cell culture as a source for cell replacement therapy in ocular diseases. Human cadaver globes were used to isolate RPE cells. Each globe was cut into several pieces of a few millimeters in size. After removing the sclera and choroid, remaining tissues were washed in phosphate buffer saline and RPE cells were isolated using dispase enzyme solution and cultured in Dulbecco's Modified Eagle's Medium: Nutrient Mixture F-12 supplemented with 10% fetal calf serum. Primary cultures of RPE cells were established and spheroid colonies related to progenitor/stem cells developed in a number of cultures. The colonies included purely pigmented or mixed pigmented and non-pigmented cells. After multiple cellular passages, several types of photoreceptors and neural-like cells were detected morphologically. Cellular plasticity in RPE cell cultures revealed promising results in terms of generation of stem/progenitor cells from human RPE cells. Whether the spheroids and neural-like retinal cells were directly derived from retinal stem cells or offspring of trans-differentiating or de-differentiating RPE cells remains to be answered.

RETINAL DISEASES IN A TERTIARY HOSPITAL IN SOUTHERN NIGERIA.

PubMed

Uhumwangho, O M; Itina, E I

2015-01-01

Retinal diseases are an important and common cause of ophthalmic consultation. To determine the pattern of retinal diseases in the ophthalmic department of a tertiary hospital in Southern Nigeria. A retrospective review of the case folders of patients with retinal pathologies seen between 2012 and 2013 was performed. Relevant demographic and clinical data was recorded. Analysis was performed for frequencies, proportions and percentages with the GraphPad Instat Software, Inc. version V2.05a program, San Diego, CA. There were 185 patients made of 94 (50.8%) males and 91 (49.2%) females with a peak age group of 61-70 years, (range 1-85 years) who made consultations for retinal diseases. Age related macular degeneration, 37(15.0%), and macula hole, 10(4.0%), were the common macula pathologies while retinal detachment, 11(4.5%), was the most common condition that required emergency vitreo-retinal surgical intervention. Diabetic retinopathy/maculopathy, 31(12.6%), hypertensive retinopathy 22(8.9%), and retinal vascular occlusion 12(4.8%), were the common retinal vascular diseases found. Bilateral visual impairment (low vision and blindness) from retinal diseases was present in 28(14.4%) persons. The common vitreo-retinal treatment options were use of intravitreal antivascular endothelial growth factors 32(13.0%), laser 16(6.5%), and vitreoretinal surgery in 22(8.9%) eyes. Retinal diseases remain an important cause of ophthalmic consultation and visual loss. Provision of facilities to manage these conditions will improve service delivery and quality of lives of affected patients.

Severe Intrapartum Asphyxia from Subamniotic Hemorrhage.

PubMed

Lo, Tsz-Kin; Lee, Andrea; Chan, Wan-Pang; Hui, Sze-Ki; Fu, Yu-Ming; Shek, Chi-Chiu; Lam, Angus

2016-01-01

Subamniotic hemorrhage results from rupture of chorionic vessels near the cord insertion. In the literature, it has never been a major cause for severe intrapartum complications. We report the first case of acute massive subamniotic hemorrhage intrapartum resulting in severe perinatal asphyxia.

Progress toward the maintenance and repair of degenerating retinal circuitry.

PubMed

Vugler, Anthony A

2010-01-01

Retinal diseases such as age-related macular degeneration and retinitis pigmentosa remain major causes of severe vision loss in humans. Clinical trials for treatment of retinal degenerations are underway and advancements in our understanding of retinal biology in health/disease have implications for novel therapies. A review of retinal biology is used to inform a discussion of current strategies to maintain/repair neural circuitry in age-related macular degeneration, retinitis pigmentosa, and Type 2 Leber congenital amaurosis. In age-related macular degeneration/retinitis pigmentosa, a progressive loss of rods/cones results in corruption of bipolar cell circuitry, although retinal output neurons/photoreceptive melanopsin cells survive. Visual function can be stabilized/enhanced after treatment in age-related macular degeneration, but in advanced degenerations, reorganization of retinal circuitry may preclude attempts to restore cone function. In Type 2 Leber congenital amaurosis, useful vision can be restored by gene therapy where central cones survive. Remarkable progress has been made in restoring vision to rodents using light-responsive ion channels inserted into bipolar cells/retinal ganglion cells. Advances in genetic, cellular, and prosthetic therapies show varying degrees of promise for treating retinal degenerations. While functional benefits can be obtained after early therapeutic interventions, efforts should be made to minimize circuitry changes as soon as possible after rod/cone loss. Advances in retinal anatomy/physiology and genetic technologies should allow refinement of future reparative strategies.

Fetal intracranial hemorrhage. Imaging by ultrasound and magnetic resonance imaging.

PubMed

Kirkinen, P; Partanen, K; Ryynänen, M; Ordén, M R

1997-08-01

To describe the magnetic resonance imaging (MRI) findings associated with fetal intracranial hemorrhage and to compare them with ultrasound findings. In four pregnancies complicated by fetal intracranial hemorrhage, fetal imaging was carried out using T2-weighted fast spin echo sequences and T1-weighted fast low angle shot imaging sequences and by transabdominal ultrasonography. An antepartum diagnosis of hemorrhage was made by ultrasound in one case and by MRI in two. Retrospectively, the hemorrhagic area could be identified from the MRI images in an additional two cases and from the ultrasound images in one case. In the cases of intraventricular hemorrhage, the MRI signal intensity in the T1-weighted images was increased in the hemorrhagic area as compared to the contralateral ventricle and brain parenchyma. In a case with subdural hemorrhage, T2-weighted MRI signals from the hemorrhagic area changed from low-to high-intensity signals during four weeks of follow-up. Better imaging of the intracranial anatomy was possible by MRI than by transabdominal ultrasonography. MRI can be used for imaging and dating fetal intracranial hemorrhages. Variable ultrasound and MRI findings are associated with this complication, depending on the age and location of the hemorrhage.

Adaptive Optics Technology for High-Resolution Retinal Imaging

PubMed Central

Lombardo, Marco; Serrao, Sebastiano; Devaney, Nicholas; Parravano, Mariacristina; Lombardo, Giuseppe

2013-01-01

Adaptive optics (AO) is a technology used to improve the performance of optical systems by reducing the effects of optical aberrations. The direct visualization of the photoreceptor cells, capillaries and nerve fiber bundles represents the major benefit of adding AO to retinal imaging. Adaptive optics is opening a new frontier for clinical research in ophthalmology, providing new information on the early pathological changes of the retinal microstructures in various retinal diseases. We have reviewed AO technology for retinal imaging, providing information on the core components of an AO retinal camera. The most commonly used wavefront sensing and correcting elements are discussed. Furthermore, we discuss current applications of AO imaging to a population of healthy adults and to the most frequent causes of blindness, including diabetic retinopathy, age-related macular degeneration and glaucoma. We conclude our work with a discussion on future clinical prospects for AO retinal imaging. PMID:23271600

Ischaemia-reperfusion injury in central retinal artery occlusion.

PubMed

Saxena, Sandeep; Mishra, Nibha; Meyer, Carsten H; Akduman, Levent

2013-10-21

A 53-year-old man presented with sudden painless diminution of vision in his right eye for 3 days. His fundus examination showed diffuse whitening of the retina with a cherry red spot at the fovea with cilioretinal artery sparing. On fluorescein angiography delayed arteriovenous transit was observed. Three-dimensional spectral domain optical coherence tomography was used to assess retinal nerve fibre layer thickness and average macular central subfield thickness on days 3, 7, 30 and 90. Marked retinal oedema due to ischaemia was observed on day 3 of occurrence of central retinal artery occlusion. On day 7, significant decrease in retinal nerve fibre thickness and macular thickness was noted suggestive of acute reperfusion injury. Retinal nerve fibre layer thickness and macular thickness returned to near normal on day 30 due to restoration of blood supply with wash out of stress mediators. Retinal atrophy was observed on day 90.

Ribavirin Prophylaxis and Therapy for Experimental Argentine Hemorrhagic Fever

DTIC Science & Technology

1988-09-01

for Experimental Argentine WD Hemorrhagic Fever KELLY T. McKEE, JR., . JOHN W. HUGGINS, 2 CREIGHTON J. TRAHAN, - AND BILL G. MAHLANDT’ Disease...ribavirin to assess the potential of this drug for treating humans with Argentine hemorrhagic fever . When ribavirin was administeredgintramuscularly...treating humans with Argentine hemorrhagic fever . - Argentine hemorrhagic fever (AHF) is a debilitating, ro- investigations suggest that ribavirin may be

Role of Hydrogen Sulfide in Retinal Diseases.

PubMed

Du, Jiantong; Jin, Hongfang; Yang, Liu

2017-01-01

As the third gasotransmitter, hydrogen sulfide (H 2 S) plays a crucial role in the physiology and pathophysiology of many systems in the body, such as the nervous, cardiovascular, respiratory, and gastrointestinal systems. The mechanisms for its effects, including inhibiting ischemic injury, reducing oxidative stress damage, regulating apoptosis, and reducing the inflammation reaction in different systems, have not been fully understood. Recently, H 2 S and its endogenous synthesis pathway were found in the mammalian retina. This review describes the production and the metabolism of H 2 S and the evidence of a role of H 2 S in the retina physiology and in the different retinal diseases, including retinal degenerative diseases and vascular diseases. In the retina, H 2 S is generated in the presence of cystathionine-β-synthase, cystathionine-γ-lyase, and 3-mercaptopyruvate sulfurtransferase from L-cysteine. The role of endogenous H 2 S and its physiologic effect in the retina are still elusive. However, strong evidence shows that retina-derived H 2 S might play protective or deleterious role in the pathogenesis of retinal diseases. For example, by regulating Ca 2+ influx, H 2 S can protect retinal neurons against light-induced degeneration. H 2 S preconditioning can mediate the anti-apoptotic effect of retinal ganglion cells in retinal ischemia/reperfusion injury. Treatment with H 2 S in rats relieves diabetic retinopathy by suppressing oxidative stress and reducing inflammation. Further studies would greatly improve our understanding of the pathophysiologic mechanisms responsible for retinal diseases and the potential for the H 2 S-related therapy of the retinal diseases as well.

Retinal Image Quality During Accommodation

PubMed Central

López-Gil, N.; Martin, J.; Liu, T.; Bradley, A.; Díaz-Muñoz, D.; Thibos, L.

2013-01-01

Purpose We asked if retinal image quality is maximum during accommodation, or sub-optimal due to accommodative error, when subjects perform an acuity task. Methods Subjects viewed a monochromatic (552nm), high-contrast letter target placed at various viewing distances. Wavefront aberrations of the accommodating eye were measured near the endpoint of an acuity staircase paradigm. Refractive state, defined as the optimum target vergence for maximising retinal image quality, was computed by through-focus wavefront analysis to find the power of the virtual correcting lens that maximizes visual Strehl ratio. Results Despite changes in ocular aberrations and pupil size during binocular viewing, retinal image quality and visual acuity typically remain high for all target vergences. When accommodative errors lead to sub-optimal retinal image quality, acuity and measured image quality both decline. However, the effect of accommodation errors of on visual acuity are mitigated by pupillary constriction associated with accommodation and binocular convergence and also to binocular summation of dissimilar retinal image blur. Under monocular viewing conditions some subjects displayed significant accommodative lag that reduced visual performance, an effect that was exacerbated by pharmacological dilation of the pupil. Conclusions Spurious measurement of accommodative error can be avoided when the image quality metric used to determine refractive state is compatible with the focusing criteria used by the visual system to control accommodation. Real focusing errors of the accommodating eye do not necessarily produce a reliably measurable loss of image quality or clinically significant loss of visual performance, probably because of increased depth-of-focus due to pupil constriction. When retinal image quality is close to maximum achievable (given the eye’s higher-order aberrations), acuity is also near maximum. A combination of accommodative lag, reduced image quality, and reduced

Retinal Optical Coherence Tomography Imaging

NASA Astrophysics Data System (ADS)

Drexler, Wolfgang; Fujimoto, James G.

The eye is essentially transparent, transmitting light with only minimal optical attenuation and scattering providing easy optical access to the anterior segment as well as the retina. For this reason, ophthalmic and especially retinal imaging has been not only the first but also most successful clinical application for optical coherence tomography (OCT). This chapter focuses on the development of OCT technology for retinal imaging. OCT has significantly improved the potential for early diagnosis, understanding of retinal disease pathogenesis, as well as monitoring disease progression and response to therapy. Development of ultrabroad bandwidth light sources and high-speed detection techniques has enabled significant improvements in ophthalmic OCT imaging performance, demonstrating the potential of three-dimensional, ultrahigh-resolution OCT (UHR OCT) to perform noninvasive optical biopsy of the living human retina, i.e., the in vivo visualization of microstructural, intraretinal morphology in situ approaching the resolution of conventional histopathology. Significant improvements in axial resolution and speed not only enable three-dimensional rendering of retinal volumes but also high-definition, two-dimensional tomograms, topographic thickness maps of all major intraretinal layers, as well as volumetric quantification of pathologic intraretinal changes. These advances in OCT technology have also been successfully applied in several animal models of retinal pathologies. The development of light sources emitting at alternative wavelengths, e.g., around #1,060 nm, not only enabled three-dimensional OCT imaging with enhanced choroidal visualization but also improved OCT performance in cataract patients due to reduced scattering losses in this wavelength region. Adaptive optics using deformable mirror technology, with unique high stroke to correct higher-order ocular aberrations, with specially designed optics to compensate chromatic aberration of the human eye, in

Unclear-onset intracerebral hemorrhage: Clinical characteristics, hematoma features, and outcomes.

PubMed

Inoue, Yasuteru; Miyashita, Fumio; Koga, Masatoshi; Minematsu, Kazuo; Toyoda, Kazunori

2017-12-01

Background and purpose Although unclear-onset ischemic stroke, including wake-up ischemic stroke, is drawing attention as a potential target for reperfusion therapy, acute unclear-onset intracerebral hemorrhage has been understudied. Clinical characteristics, hematoma features, and outcomes of patients who developed intracerebral hemorrhage during sleep or those with intracerebral hemorrhage who were unconscious when witnessed were determined. Methods Consecutive intracerebral hemorrhage patients admitted within 24 hours after onset or last-known normal time were classified into clear-onset intracerebral hemorrhage and unclear-onset intracerebral hemorrhage groups. Outcomes included initial hematoma volume, initial National Institutes of Health Stroke Scale score, hematoma growth on 24-hour follow-up computed tomography, and vital and functional prognoses at 30 days. Results Of 377 studied patients (122 women, 69 ± 11 years old), 147 (39.0%) had unclear-onset intracerebral hemorrhage. Patients with unclear-onset intracerebral hemorrhage had larger hematoma volumes (p = 0.044) and higher National Institutes of Health Stroke Scale scores (p < 0.001) than those with clear-onset intracerebral hemorrhage after multivariable adjustment for risk factors and comorbidities. Hematoma growth was similarly common between the two groups (p = 0.176). There were fewer patients with modified Rankin Scale (mRS) scores of 0-2 (p = 0.033) and more patients with mRS scores of 5-6 (p = 0.009) and with fatal outcomes (p = 0.049) in unclear-onset intracerebral hemorrhage group compared with clear-onset intracerebral hemorrhage as crude values, but not after adjustment. Conclusions Patients with unclear-onset intracerebral hemorrhage presented with larger hematomas and higher National Institutes of Health Stroke Scale scores at emergent visits than those with clear-onset intracerebral hemorrhage, independent of underlying characteristics. Unclear

Inner neural retina loss in central retinal artery occlusion.

PubMed

Ikeda, Fumiko; Kishi, Shoji

2010-09-01

To report morphologic retinal changes and visual outcomes in acute and chronic central retinal artery occlusion (CRAO). We reviewed ten eyes of ten patients with CRAO (age, 65.3 ± 10.2 years) and measured retinal thicknesses at the central fovea and the perifovea using optical coherence tomography (OCT) over 8 ± 4 months. During the acute phase (within 10 days), the mean inner retinal thicknesses were 148% and 139% of normal values at 1 mm nasal and temporal to the fovea. They decreased to 22% and 11% of normal inner retinal thickness during the chronic phase (3 months or later). The retinal thickness at the perifovea decreased linearly until 3 months but was stable during the chronic phase. In contrast, the foveal thickness increased slightly in the acute phase but was equivalent to the normal level during the chronic phase. As a result of inner retinal atrophy, the foveal pit was shallow during the chronic phase. The final visual acuity was correlated positively with retinal thickness at the perifovea during the chronic CRAO phase. OCT showed that inner retinal necrosis with early swelling and late atrophy occurred in CRAO. The fovea and outer retina appeared to be excluded from ischemic change. The residual inner retina at the perifovea determined the final visual outcomes.

Genetics Home Reference: hereditary hemorrhagic telangiectasia

MedlinePlus

... Central OMIM: JUVENILE POLYPOSIS/HEREDITARY HEMORRHAGIC TELANGIECTASIA SYNDROME McDonald J, Bayrak-Toydemir P, Pyeritz RE. Hereditary hemorrhagic ... 10.1097/GIM.0b013e3182136d32. Review. Citation on PubMed McDonald J, Wooderchak-Donahue W, VanSant Webb C, Whitehead ...

Recurrent hemorrhage from corpus luteum during anticoagulant therapy.

PubMed Central

Wong, K. P.; Gillett, P. G.

1977-01-01

A 43-year old woman had recurrent massive intraperitoneal hemorrhage from rupture of a hemorrhagic corpus luteum in two successive menstrual cycles while receiving anticoagulant therapy. Left oophorectomy was performed on the first occasion and right salpingo-oophorectomy with left salpingectomy on the second. While the precise incidence cannot be determined, rupture from a hemorrhagic corpus luteum appears to be a rare but potentially catastrophic complication of anticoagulant therapy. Hence possible ovarian hemorrhage should be considered in women of reproductive age receiving heparin or sodium warfarin therapy. PMID:844024

Coats-like retinitis pigmentosa: Reports of three cases.

PubMed

Kan, Emrah; Yilmaz, Turgut; Aydemir, Orhan; Güler, Mete; Kurt, Jülide

2007-06-01

Describing the ophthalmic findings of an exudative vasculopathy called as Coats-like retinitis pigmentosa on three patients. The etiology of the Coats-like retinitis pigmentosa is obscure. The principal theories have been discussed in this article. Three observational case series have been discussed. Complete ophthalmic examinations and color fundus photos, visual field, and fluorescein angiography have been performed. We have identified 3 patients who have some typical clinical features of Coats-like retinitis pigmentosa; peripheral serous retinal detachment, telangiectasia, prominent lipid deposition, pigmentary changes in peripheral retina, and loss of vision. None of the three patients had positive family history. All of the patients have had symptoms of nyctalopia, decreased central vision, and two of them have had constriction of visual field. All of the patients have had cataracts and two of them underwent cataract surgery. Fundus examination and fluorescein angiography of patients revealed typical retinitis pigmentosa with Coats-type changes in bilateral inferiotemporal quadrants. A better understanding of clinical features and genetic etiology of Coats-type retinitis pigmentosa will aid diagnosis and development of new therapies. If sufficient conditions arise, genetic factors that influence the expression of CRB1 mutations in Coats-like retinitis pigmentosa should be detected.

Retinal tear: an unusual complication of ocular toxoplasmosis.

PubMed

Celebi, Ali Riza Cenk; Kilavuzoglu, Ayse Ebru; Altiparmak, Ugur Emrah; Cosar, Cemile Banu; Ozkiris, Abdullah

2015-01-01

It is aimed to report on a 16-year-old patient with acquired ocular toxoplasmosis complicated by a retinal tear. Retrospective medical chart review. A 16-year-old Caucasian female presented with vision loss in her right eye. In addition to a white active lesion between the fovea and the optic nerve head, marked vitreous opacification was noted. She was diagnosed with ocular toxoplasmosis. The patient was treated with oral azithromycin, clindamycin, and trimethoprimsulfamethoxazole. One month later, retinochoroiditis resolved and vitreous cleared. Three months after onset, patient presented with floaters in the right eye and a retinal tear was located at the temporal region of the retina. Prophylactic argon laser treatment that encircled the retinal tear was performed. No other abnormalities were noted during 6 months of follow-up. Retinal tear associated with ocular toxoplasmosis is rare; however, a retinal tear can occur due to vitreoretinal traction following post-inflammatory structural alteration of the vitreous. Retinal tears may be seen during the healing phase, when the inflammation turns into tightening of vitreous substance. Careful retinal examination in cases of ocular toxoplasmosis is warranted, especially in patients with severe vitreous inflammation.

Overview of ultrasound-induced lung hemorrhage

NASA Astrophysics Data System (ADS)

O'Brien, William D.; Simpson, Douglas G.; Frizzell, Leon A.; Oelze, Michael L.; Zachary, James F.

2003-10-01

It is well documented that ultrasound-induced lung hemorrhage can occur in mice, rats, rabbits, pigs, and monkeys. Our own experimental studies have focused on mice, rats, and pigs as animal models. The characteristics of the lesions produced in mice, rats and pigs were similar to those described in studies by our research group and others, suggesting a common pathogenesis for the initiation and propagation of the lesions at the macroscopic and microscopic levels. Five experimental in vivo studies have been conducted to evaluate whether cavitation is responsible for ultrasound-induced lung hemorrhage. The studies evaluated the dependencies of hydrostatic pressure, frequency, pulse polarity, contrast agents and lung inflation, and the results of each study appeared inconsistent with the hypothesis that the mechanism for the production of a lung hemorrhage was inertial cavitation. Other dependencies evaluated included beam width, pulse repetition frequency, pulse duration, exposure duration, and animal species and age. The thresholds for producing ultrasound-induced lung hemorrhage, in general, were less than the FDA's regulatory limit of a Mechanical Index (MI) of 1.9. Further, the MI does not appear to provide a risk-based index for lung hemorrhage. [Work supported by NIH Grant No. R01EB02641.

Retinal diseases in a tertiary hospital: the need for establishment of a vitreo-retinal care unit.

PubMed

Onakpoya, Oluwatoyin Helen; Olateju, Samuel Oluremi; Ajayi, Iyiade Adeseye

2008-11-01

To evaluate the need for vitreo-retinal care for suburban and rural communities of southwestern Nigeria. A retrospective review of patients with posterior segment diseases attending the general ophthalmology clinics of Obafemi Awolowo University Teaching Hospital's complex, Ile Ife, southwestern Nigeria, between January 2001 and December 2006 was conducted. The age, sex and diagnosis were analyzed and needs assessment conducted. Three-thousand, one-hundred-thirty-one new cases were reviewed of which 407(13%) patients presented with retinal diseases. Their mean age was 46.3 +/- 21.4 years, mode 60 years and male:female ratio 1.3:1 (P=0.05). Macula diseases (35.6%), hypertensive retinopathy (12%), retinochoroiditis (11.5%) and diabetic retinopathy (9.6%) were the predominant retinal diseases. Age-related macular degeneration was the most frequent of the macular diseases (38.6%), with a female preponderance (p=0.06). It is estimated that fundus photography +/- fluorescein will be beneficial in 89.4%, laser photocoagulation in 36.4% and vitreo-retinal surgical procedure in 16.4%. Posterior segment diseases are not uncommon in rural communities of southwestern Nigeria. Facilities for fundus angiography, laser photocoagulation and a vitreoretinal surgical unit in trained hands will improve the capacity for specific diagnosis and appropriate management of vitreo-retinal diseases in these communities.

Subretinal transplantation of bone marrow mesenchymal stem cells delays retinal degeneration in the RCS rat model of retinal degeneration.

PubMed

Inoue, Yuji; Iriyama, Aya; Ueno, Shuji; Takahashi, Hidenori; Kondo, Mineo; Tamaki, Yasuhiro; Araie, Makoto; Yanagi, Yasuo

2007-08-01

Because there is no effective treatment for this retinal degeneration, potential application of cell-based therapy has attracted considerable attention. Several investigations support that bone marrow mesenchymal stem cells (MSCs) can be used for a broad spectrum of indications. Bone marrow MSCs exert their therapeutic effect in part by secreting trophic factors to promote cell survival. The current study investigates whether bone marrow MSCs secrete factor(s) to promote photoreceptor cell survival and whether subretinal transplantation of bone marrow MSCs promotes photoreceptor survival in a retinal degeneration model using Royal College of Surgeons (RCS) rats. In vitro, using mouse retinal cell culture, it was demonstrated that the conditioned medium of the MSCs delays photoreceptor cell apoptosis, suggesting that the secreted factor(s) from the MSCs promote photoreceptor cell survival. In vivo, the MSCs were injected into the subretinal space of the RCS rats and histological analysis, real-time RT-PCR and electrophysiological analysis demonstrated that the subretinal transplantation of MSCs delays retinal degeneration and preserves retinal function in the RCS rats. These results suggest that MSC is a useful cell source for cell-replacement therapy for some forms of retinal degeneration.

Intracranial hemorrhage in infective endocarditis: A case report

PubMed Central

Aziz, Fahad; Perwaiz, Saira; Penupolu, Sudheer; Doddi, Sujatha; Gongireddy, Srinivas

2011-01-01

Cerebral hemorrhage occurs rarely in infective endocarditis. Here, we present an interesting case of infective endocarditis complicated by sever cerebral hemorrhage. Later, his blood culture grew S bovis. To the best of our knowledge, this is the first ever reported case of S Bovis infective endocarditis complicated by extensive intracranial hemorrhage. PMID:22263076

Optical Coherence Tomography Angiography in Retinal Diseases.

PubMed

Chalam, K V; Sambhav, Kumar

2016-01-01

Optical coherence tomography angiography (OCTA) is a new, non-invasive imaging system that generates volumetric data of retinal and choroidal layers. It has the ability to show both structural and blood flow information. Split-spectrum amplitude-decorrelation angiography (SSADA) algorithm (a vital component of OCTA software) helps to decrease the signal to noise ratio of flow detection thus enhancing visualization of retinal vasculature using motion contrast. Published studies describe potential efficacy for OCTA in the evaluation of common ophthalmologic diseases such as diabetic retinopathy, age related macular degeneration (AMD), retinal vascular occlusions and sickle cell disease. OCTA provides a detailed view of the retinal vasculature, which allows accurate delineation of microvascular abnormalities in diabetic eyes and vascular occlusions. It helps quantify vascular compromise depending upon the severity of diabetic retinopathy. OCTA can also elucidate the presence of choroidal neovascularization (CNV) in wet AMD. In this paper, we review the knowledge, available in English language publications regarding OCTA, and compare it with the conventional angiographic standard, fluorescein angiography (FA). Finally, we summarize its potential applications to retinal vascular diseases. Its current limitations include a relatively small field of view, inability to show leakage, and tendency for image artifacts. Further larger studies will define OCTA's utility in clinical settings and establish if the technology may offer a non-invasive option of visualizing the retinal vasculature, enabling us to decrease morbidity through early detection and intervention in retinal diseases.

Optical Coherence Tomography Angiography in Retinal Diseases

PubMed Central

Chalam, K. V.; Sambhav, Kumar

2016-01-01

Optical coherence tomography angiography (OCTA) is a new, non-invasive imaging system that generates volumetric data of retinal and choroidal layers. It has the ability to show both structural and blood flow information. Split-spectrum amplitude-decorrelation angiography (SSADA) algorithm (a vital component of OCTA software) helps to decrease the signal to noise ratio of flow detection thus enhancing visualization of retinal vasculature using motion contrast. Published studies describe potential efficacy for OCTA in the evaluation of common ophthalmologic diseases such as diabetic retinopathy, age related macular degeneration (AMD), retinal vascular occlusions and sickle cell disease. OCTA provides a detailed view of the retinal vasculature, which allows accurate delineation of microvascular abnormalities in diabetic eyes and vascular occlusions. It helps quantify vascular compromise depending upon the severity of diabetic retinopathy. OCTA can also elucidate the presence of choroidal neovascularization (CNV) in wet AMD. In this paper, we review the knowledge, available in English language publications regarding OCTA, and compare it with the conventional angiographic standard, fluorescein angiography (FA). Finally, we summarize its potential applications to retinal vascular diseases. Its current limitations include a relatively small field of view, inability to show leakage, and tendency for image artifacts. Further larger studies will define OCTA's utility in clinical settings and establish if the technology may offer a non-invasive option of visualizing the retinal vasculature, enabling us to decrease morbidity through early detection and intervention in retinal diseases. PMID:27195091

Screening retinal transplants with Fourier-domain OCT

NASA Astrophysics Data System (ADS)

Rao, Bin

2009-02-01

Transplant technologies have been studied for the recovery of vision loss from retinitis pigmentosa (RP) and age-related macular degeneration (AMD). In several rodent retinal degeneration models and in patients, retinal progenitor cells transplanted as layers to the subretinal space have been shown to restore or preserve vision. The methods for evaluation of transplants are expensive considering the large amount of animals. Alternatively, time-domain Stratus OCT was previously shown to be able to image the morphological structure of transplants to some extent, but could not clearly identify laminated transplants. The efficacy of screening retinal transplants with Fourier-domain OCT was studied on 37 S334ter line 3 rats with retinal degeneration 6-67 days after transplant surgery. The transplants were morphologically categorized as no transplant, detachment, rosettes, small laminated area and larger laminated area with both Fourier-domain OCT and histology. The efficacy of Fourier-domain OCT in screening retinal transplants was evaluated by comparing the categorization results with OCT and histology. Additionally, 4 rats were randomly selected for multiple OCT examinations (1, 5, 9, 14 and 21days post surgery) in order to determine the earliest image time of OCT examination since the transplanted tissue may need some time to show its tendency of growing. Finally, we demonstrated the efficacy of Fourier-domain OCT in screening retinal transplants in early stages and determined the earliest imaging time for OCT. Fourier-domain OCT makes itself valuable in saving resource spent on animals with unsuccessful transplants.

Retinoids and Retinal Diseases

PubMed Central

Kiser, Philip D.; Palczewski, Krzysztof

2016-01-01

Recent progress in molecular understanding of the retinoid cycle in mammalian retina stems from painstaking biochemical reconstitution studies supported by natural or engineered animal models with known genetic lesions and studies of humans with specific genetic blinding diseases. Structural and membrane biology have been used to detect critical retinal enzymes and proteins and their substrates and ligands, placing them in a cellular context. These studies have been supplemented by analytical chemistry methods that have identified small molecules by their spectral characteristics, often in conjunction with the evaluation of models of animal retinal disease. It is from this background that rational therapeutic interventions to correct genetic defects or environmental insults are identified. Thus, most presently accepted modulators of the retinoid cycle already have demonstrated promising results in animal models of retinal degeneration. These encouraging signs indicate that some human blinding diseases can be alleviated by pharmacological interventions. PMID:27917399

BK virus-associated hemorrhagic cystitis after pediatric stem cell transplantation

PubMed Central

Han, Seung Beom; Kang, Jin Han

2014-01-01

Hemorrhagic cystitis is a common stem cell transplantation-related complication. The incidence of early-onset hemorrhagic cystitis, which is related to the pretransplant conditioning regimen, has decreased with the concomitant use of mesna and hyperhydration. However, late-onset hemorrhagic cystitis, which is usually caused by the BK virus, continues to develop. Although the BK virus is the most common pathogenic microorganism of poststem cell transplantation late-onset hemorrhagic cystitis, pediatricians outside the hemato-oncology and nephrology specialties tend to be unfamiliar with hemorrhagic cystitis and the BK virus. Moreover, no standard guidelines for the early diagnosis and treatment of BK virus-associated hemorrhagic cystitis after stem cell transplantation have been established. Here, we briefly introduce poststem cell transplantation BK virus-associated hemorrhagic cystitis. PMID:25653684

Treatment of laser-induced retinal injuries by neuroprotection

NASA Astrophysics Data System (ADS)

Solberg, Yoram; Rosner, Mordechai; Belkin, Michael

1997-05-01

Retinal laser photocoagulation treatments are often complicated with immediate side-effect of visual impairment. To determine whether glutamate-receptor blockers can serve as adjuvant neuroprotective therapy, we examined the effect of MK-801, an NMDA-receptor antagonist, on laser-induced retinal injury in a rat model. Argon laser retinal lesions were created in the retina of 36 DA rats. Treatment with intraperitoneal injections of MK-801 or saline was started immediately after the laser photocoagulation. The animals were sacrificed after 3, 20 or 60 days and the retinal lesions were evaluated histologically and morphometrically. Photoreceptor-cell loss was significantly smaller in MK-801-treated rats than controls. The proliferative membrane composed of retinal pigment epithelial cells which was seen at the base of the lesion in control retinas, was smaller in the MK-801-treated retinas. MK-801 exhibited neuroprotective and anti-proliferative properties in the retina. Glutamate-receptor blockers should be further investigated for serving as adjuvant therapy to retinal photocoagulation treatments.

Ischaemia-reperfusion injury in central retinal artery occlusion

PubMed Central

Saxena, Sandeep; Mishra, Nibha; Meyer, Carsten H; Akduman, Levent

2013-01-01

A 53-year-old man presented with sudden painless diminution of vision in his right eye for 3 days. His fundus examination showed diffuse whitening of the retina with a cherry red spot at the fovea with cilioretinal artery sparing. On fluorescein angiography delayed arteriovenous transit was observed. Three-dimensional spectral domain optical coherence tomography was used to assess retinal nerve fibre layer thickness and average macular central subfield thickness on days 3, 7, 30 and 90. Marked retinal oedema due to ischaemia was observed on day 3 of occurrence of central retinal artery occlusion. On day 7, significant decrease in retinal nerve fibre thickness and macular thickness was noted suggestive of acute reperfusion injury. Retinal nerve fibre layer thickness and macular thickness returned to near normal on day 30 due to restoration of blood supply with wash out of stress mediators. Retinal atrophy was observed on day 90. PMID:24145508

Oxygen-induced retinopathy in mice with retinal photoreceptor cell degeneration.

PubMed

Zhang, Qian; Zhang, Zuo-Ming

2014-04-25

It is reported that retinal neovascularization seems to rarely co-exist with retinitis pigmentosa in patients and in some mouse models; however, it is not widely acknowledged as a universal phenomenon in all strains of all animal species. We aimed to further explore this phenomenon with an oxygen-induced retinopathy model in mice with retinal photoreceptor cell degeneration. Oxygen-induced retinopathy of colored and albino mice with rapid retinal degeneration were compared to homologous wild-type mice. The retinas were analyzed using high-molecular-weight FITC-dextran stained flat-mount preparation, hematoxylin and eosin (H&E) stained cross-sections, an immunohistochemical test for vascular endothelial growth factor (VEGF) distribution and Western blotting for VEGF expression after exposure to hyperoxia between postnatal days 17 (P17) and 21. Leakage and areas of non-perfusion of the retinal blood vessels were alleviated in the retinal degeneration mice. The number of preretinal vascular endothelial cell nuclei in the retinal degeneration mice was smaller than that in the homologous wild-type mice after exposure to hyperoxia (P<0.01). The degree of oxygen-induced retinopathy was positively correlated with the VEGF expression level. However, the VEGF expression level was lower in the retinal degeneration mice. Proliferative retinopathy occurred in mice with rapid retinal degeneration, but retinal photoreceptor cell degeneration could partially restrain the retinal neovascularization in this rapid retinal degeneration mouse model. Copyright © 2014 Elsevier Inc. All rights reserved.

Effects of Infrared Laser Radiation on the In Vitro Isomerization of All-Trans Retinal to 11-Cis Retinal

PubMed Central

Liegner, J.; Taboada, J.; Tsin, A. T. C.

2015-01-01

The in vitro effect of infrared laser light on the isomerization of all-trans retinal dissolved in an ether/hexane and also an ethanol solvent was studied. Pulsed laser energy at 1064 nm was used to drive the molecular reconfiguration of all-trans retinal to 11-cis retinal. High pressure liquid chromatography (HPLC) was used to quantify the conversion. Overall isomerization was minimal (0.2 percent to 1.0 percent), yet, a significant difference in isomerization due to pulsed infrared laser energy over non-modulated monochromatic laser light was detected (up to 168 percent difference). Potentially, pulsed laser radiation tuned to the ethylenic stretch frequency of the C11=C12 bond of retinal may induce rotational changes to the chromophore. PMID:26321787

Simulation Study of an Ultrasound Retinal Prosthesis With a Novel Contact-Lens Array for Noninvasive Retinal Stimulation.

PubMed

Gao, Mengdi; Yu, Yanyan; Zhao, Huixia; Li, Guofeng; Jiang, Hongyang; Wang, Congzhi; Cai, Feiyan; Chan, Leanne Lai-Hang; Chiu, Bernard; Qian, Wei; Qiu, Weibao; Zheng, Hairong

2017-09-01

Millions of people around the world suffer from varying degrees of vision loss (including complete blindness) because of retinal degenerative diseases. Artificial retinal prosthesis, which is usually based on electrical neurostimulation, is the most advanced technology for different types of retinal degeneration. However, this technology involves placing a device into the eyeball, and such a highly invasive procedure is inevitably highly risk and expensive. Ultrasound has been demonstrated to be a promising technology for noninvasive neurostimulation, making it possible to stimulate the retina and induce action potentials similar to those elicited by light stimulation. However, the technology of ultrasound retinal stimulation still requires considerable developments before it could be applied clinically. This paper proposes a novel contact-lens array transducer for use in an ultrasound retinal prosthesis (USRP). The transducer was designed in the shape of a contact lens so as to facilitate acoustic coupling with the eye liquid. The key parameters of the ultrasound transducer were simulated, and results are presented that indicate the achievement of 2-D pattern generation and that the proposed contact-lens array is suitable for multiple-focus neurostimulation, and can be used in a USRP.

Müller stem cell dependent retinal regeneration.

PubMed

Chohan, Annu; Singh, Usha; Kumar, Atul; Kaur, Jasbir

2017-01-01

Müller Stem cells to treat ocular diseases has triggered enthusiasm across all medical and scientific communities. Recent development in the field of stem cells has widened the prospects of applying cell based therapies to regenerate ocular tissues that have been irreversibly damaged by disease or injury. Ocular tissues such as the lens and the retina are now known to possess cell having remarkable regenerative abilities. Recent studies have shown that the Müller glia, a cell found in all vertebrate retinas, is the primary source of new neurons, and therefore are considered as the cellular basis for retinal regeneration in mammalian retinas. Here, we review the current status of retinal regeneration of the human eye by Müller stem cells. This review elucidates the current status of retinal regeneration by Müller stem cells, along with major retinal degenerative diseases where these stem cells play regenerative role in retinal repair and replacement. Copyright © 2016. Published by Elsevier B.V.

Contribution of Microglia-Mediated Neuroinflammation to Retinal Degenerative Diseases

PubMed Central

Madeira, Maria H.; Boia, Raquel; Santos, Paulo F.; Ambrósio, António F.; Santiago, Ana R.

2015-01-01

Retinal degenerative diseases are major causes of vision loss and blindness worldwide and are characterized by chronic and progressive neuronal loss. One common feature of retinal degenerative diseases and brain neurodegenerative diseases is chronic neuroinflammation. There is growing evidence that retinal microglia, as in the brain, become activated in the course of retinal degenerative diseases, having a pivotal role in the initiation and propagation of the neurodegenerative process. A better understanding of the events elicited and mediated by retinal microglia will contribute to the clarification of disease etiology and might open new avenues for potential therapeutic interventions. This review aims at giving an overview of the roles of microglia-mediated neuroinflammation in major retinal degenerative diseases like glaucoma, age-related macular degeneration, and diabetic retinopathy. PMID:25873768

Low Vision Rehabilitation of Retinitis Pigmentosa. Practice Report

ERIC Educational Resources Information Center

Rundquist, John

2004-01-01

Retinitis pigmentosa is a rod-cone dystrophy, commonly genetic in nature. Approximately 60-80% of those with retinitis pigmentosa inherit it by an autosomal recessive transmission (Brilliant, 1999). There have been some reported cases with no known family history. The symptoms of retinitis pigmentosa are decreased acuity, photophobia, night…

Inherited Retinal Degenerative Clinical Trial Network. Addendum

DTIC Science & Technology

2013-10-01

visual impairment usually ending in blindness. In the United States, the total number of individuals affected by retinitis pigmentosa (RP) and other...linica l trial in the NEER network for autosomal dominant retinitis pigmentosa , and the ProgSTAR studies for Stargardt disease) . As new interventions b... retinitis pigmentosa continues at six sites- the CTEC site at University of Utah and five additional recruitment sites- the Retina Foundation of the

Clinical Features of Newly Diagnosed Cytomegalovirus Retinitis in Northern Thailand

PubMed Central

Ausayakhun, Somsanguan; Keenan, Jeremy D; Ausayakhun, Sakarin; Jirawison, Choeng; Khouri, Claire M; Skalet, Alison H; Heiden, David; Holland, Gary N; Margolis, Todd P

2011-01-01

Purpose To characterize the clinical manifestations of cytomegalovirus (CMV) retinitis in northern Thailand. Design Prospective, observational cross-sectional study. Methods We recorded characteristics of 52 consecutive patients newly diagnosed with CMV retinitis at a tertiary university-based medical center in northern Thailand. Indirect ophthalmoscopy by experienced ophthalmologists was supplemented with fundus photography to determine the proportion of eyes with various clinical features of CMV retinitis. Results Of the 52 patients with CMV retinitis, 55.8% were female. All were HIV-positive. The vast majority (90.4%) had started antiretroviral therapy. CMV retinitis was bilateral in 46.2% of patients. Bilateral visual acuity worse than 20/60 was observed in 23.1% of patients. Of 76 eyes with CMV retinitis, 61.8% had zone I disease and 21.6% had lesions involving the fovea. Lesions larger than 25% of the retinal area were observed in 57.5% of affected eyes. CMV retinitis lesions commonly had marked or severe border opacity (47.4% of eyes). Vitreous haze was often present (46.1% of eyes). Visual impairment was more common in eyes with larger retinitis lesions. Retinitis lesion size, used as a proxy for duration of disease, was associated with fulminant appearance (OR 1.24 [1.01 – 1.51]), and marked or severe border opacity (OR 1.36 [1.11 – 1.67]). Based on lesion size, retinitis preceded antiretroviral treatment in each patient. Conclusions Patients presenting to a tertiary medical center in northern Thailand have advanced CMV retinitis, possibly due to delayed diagnosis. Earlier screening and treatment of CMV retinitis may limit progression of disease and prevent visual impairment in this population. PMID:22265148

Layer-specific blood-flow MRI of retinitis pigmentosa in RCS rats☆

PubMed Central

Li, Guang; Garza, Bryan De La; Shih, Yen-Yu I.; Muir, Eric R.; Duong, Timothy Q.

2013-01-01

The Royal College of Surgeons (RCS) rat is an established animal model of retinitis pigmentosa, a family of inherited retinal diseases which starts with loss of peripheral vision and progresses to eventual blindness. Blood flow (BF), an important physiological parameter, is intricately coupled to metabolic function under normal physiological conditions and is perturbed in many neurological and retinal diseases. This study reports non-invasive high-resolution MRI (44 × 44 × 600 μm) to image quantitative retinal and choroidal BF and layer-specific retinal thicknesses in RCS rat retinas at different stages of retinal degeneration compared with age-matched controls. The unique ability to separate retinal and choroidal BF was made possible by the depth-resolved MRI technique. RBF decreased with progressive retinal degeneration, but ChBF did not change in RCS rats up to post-natal day 90. We concluded that choroidal and retinal circulations have different susceptibility to progressive retinal degeneration in RCS rats. Layer-specific retinal thickness became progressively thinner and was corroborated by histological analysis in the same animals. MRI can detect progressive anatomical and BF changes during retinal degeneration with laminar resolution. PMID:22721720

Layer-specific blood-flow MRI of retinitis pigmentosa in RCS rats.

PubMed

Li, Guang; De La Garza, Bryan; Shih, Yen-Yu I; Muir, Eric R; Duong, Timothy Q

2012-08-01

The Royal College of Surgeons (RCS) rat is an established animal model of retinitis pigmentosa, a family of inherited retinal diseases which starts with loss of peripheral vision and progresses to eventual blindness. Blood flow (BF), an important physiological parameter, is intricately coupled to metabolic function under normal physiological conditions and is perturbed in many neurological and retinal diseases. This study reports non-invasive high-resolution MRI (44 × 44 × 600 μm) to image quantitative retinal and choroidal BF and layer-specific retinal thicknesses in RCS rat retinas at different stages of retinal degeneration compared with age-matched controls. The unique ability to separate retinal and choroidal BF was made possible by the depth-resolved MRI technique. RBF decreased with progressive retinal degeneration, but ChBF did not change in RCS rats up to post-natal day 90. We concluded that choroidal and retinal circulations have different susceptibility to progressive retinal degeneration in RCS rats. Layer-specific retinal thickness became progressively thinner and was corroborated by histological analysis in the same animals. MRI can detect progressive anatomical and BF changes during retinal degeneration with laminar resolution. Copyright © 2012 Elsevier Ltd. All rights reserved.

Retinal adaptation to dim light vision in spectacled caimans (Caiman crocodilus fuscus): Analysis of retinal ultrastructure.

PubMed

Karl, Anett; Agte, Silke; Zayas-Santiago, Astrid; Makarov, Felix N; Rivera, Yomarie; Benedikt, Jan; Francke, Mike; Reichenbach, Andreas; Skatchkov, Serguei N; Bringmann, Andreas

2018-05-19

It has been shown that mammalian retinal glial (Müller) cells act as living optical fibers that guide the light through the retinal tissue to the photoreceptor cells (Agte et al., 2011; Franze et al., 2007). However, for nonmammalian species it is unclear whether Müller cells also improve the transretinal light transmission. Furthermore, for nonmammalian species there is a lack of ultrastructural data of the retinal cells, which, in general, delivers fundamental information of the retinal function, i.e. the vision of the species. A detailed study of the cellular ultrastructure provides a basic approach of the research. Thus, the aim of the present study was to investigate the retina of the spectacled caimans at electron and light microscopical levels to describe the structural features. For electron microscopy, we used a superfast microwave fixation procedure in order to achieve more precise ultrastructural information than common fixation techniques. As result, our detailed ultrastructural study of all retinal parts shows structural features which strongly indicate that the caiman retina is adapted to dim light and night vision. Various structural characteristics of Müller cells suppose that the Müller cell may increase the light intensity along the path of light through the neuroretina and, thus, increase the sensitivity of the scotopic vision of spectacled caimans. Müller cells traverse the whole thickness of the neuroretina and thus may guide the light from the inner retinal surface to the photoreceptor cell perikarya and the Müller cell microvilli between the photoreceptor segments. Thick Müller cell trunks/processes traverse the layers which contain light-scattering structures, i.e., nerve fibers and synapses. Large Müller cell somata run through the inner nuclear layer and contain flattened, elongated Müller cell nuclei which are arranged along the light path and, thus, may reduce the loss of the light intensity along the retinal light path. The

Retinal single-layer analysis with optical coherence tomography shows inner retinal layer thinning in Huntington's disease as a potential biomarker.

PubMed

Gulmez Sevim, Duygu; Unlu, Metin; Gultekin, Murat; Karaca, Cagatay

2018-02-12

There have been ongoing clinical trials of therapeutic agents in Huntington's disease (HD) which requires development of reliable biomarkers of disease progression. There have been studies in the literature with conflicting results on the involvement of retina in HD, and up to date there is not a study evaluating the single retinal layers in HD. We aimed to evaluate the specific retinal changes in HD and their usability as potential disease progression markers. This cross-sectional study used spectral-domain optical coherence tomography with automatic segmentation to measure peripapillary retinal nerve fiber layer (pRNFL) thickness and the thickness and volume of retinal layers in foveal scans of 15 patients with HD and 15 age- and sex-matched controls. Genetic testing results, disease duration, HD disease burden scores and Unified HD Rating Scales motor scores were acquired for the patients. Temporal pRNFL, macular RNFL (mRNFL), ganglion cell layer (GCL), inner plexiform layer (IPL), inner nuclear layer and outer plexiform layer thicknesses and IPL, retinal pigment epithelium and outer macular volume were found lower in HD compared to controls, while outer nuclear layer and outer retinal layer thickness were increased (p < 0.05). We found significant correlations between inner retinal layer thicknesses, most significantly with mRNFL and GCL and disease progression markers. The outcomes of this study points out that retinal layers, most significantly mRNFL and GCL, are strongly correlated with the disease progression in HD and could serve as useful biomarkers for disease progression.

Postpartum Hemorrhage.

PubMed

Newsome, Janice; Martin, Jonathan G; Bercu, Zachary; Shah, Jay; Shekhani, Haris; Peters, Gail

2017-12-01

Interventional radiologists are often called for emergent control of abnormal uterine bleeding. Bleeding, even heavy bleeding as a result of uterine fibroids is not a common emergent procedure; instead, pregnancy and pregnancy related conditions, trauma and malignancy associated with bleeding can be the source of many interventional radiology on call events or procedures. Postpartum hemorrhage (PPH) is the most common cause, and is defined as blood loss of 500mL after vaginal delivery or 1000mL after cesarean section. Several authors have suggested a simpler definition of any amount of blood loss that creates hemodynamic instability in the mother. Regardless, PPH can be a life-threatening emergency and is a leading cause of maternal mortality requiring prompt action. Primary PPH is bleeding within the first 24 hour of delivery and secondary PPH is hemorrhage that occurs more than 24 hour after delivery. In addition to death, other serious morbidity resulting from postpartum bleeding includes shock, adult respiratory distress syndrome, coagulopathy, and loss of fertility due to hysterectomy. Transcatheter uterine artery embolization was first introduced as a treatment for PPH in 1979. It is a nonsurgical, minimally invasive, extremely safe and effective treatment for controlling excessive bleeding of the female reproductive track usually after conservative measures have failed, yet somewhat underused. Referring providers have limited awareness of the procedure. In hospitals where interventional radiologists have the experience and technical expertise to perform pelvic arteriography and embolization, this therapeutic option can play a pivotal role in the management of emergent obstetric hemorrhage. Copyright © 2017 Elsevier Inc. All rights reserved.

Regulatory and Economic Considerations of Retinal Drugs.

PubMed

Shah, Ankoor R; Williams, George A

2016-01-01

The advent of anti-VEGF therapy for neovascular age-related macular degeneration and macular edema secondary to retinal vein occlusion and diabetes mellitus has prevented blindness in tens of thousands of people. However, the costs of these drugs are without precedent in ophthalmic drug therapeutics. An analysis of the financial implications of retinal drugs and the impact of the Food and Drug Administration on treatment of retinal disease must include not only an evaluation of the direct costs of the drugs and the costs associated with their administration, but also the cost savings which accrue from their clinical benefit. This chapter will discuss the financial and regulatory issues associated with retinal drugs. © 2016 S. Karger AG, Basel.

Embolization of Rectal Arteries: An Alternative Treatment for Hemorrhagic Shock Induced by Traumatic Intrarectal Hemorrhage

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

Pichon, Nicolas, E-mail: nicolas.pichon@unilim.fr, E-mail: nicolas.pichon@chu-limoges.fr; Francois, Bruno; Pichon-Lefievre, Florence

2005-05-15

Rectal injuries caused by foreign bodies or iatrogenic insertions may lead to severe complications whose therapeutic management remains controversial. At times, both the rapid identification and treatment of subsequent active rectal bleeding may be challenging, especially when endoscopy fails to locate and control the arterial hemorrhage. We present the first two successful cases of middle rectal artery embolization in patients presenting with sustained bleeding and hemorrhagic shock.

Comparison of diagnosis of early retinal lesions of diabetic retinopathy between a computer system and human experts.

PubMed

Lee, S C; Lee, E T; Kingsley, R M; Wang, Y; Russell, D; Klein, R; Warn, A

2001-04-01

To investigate whether a computer vision system is comparable with humans in detecting early retinal lesions of diabetic retinopathy using color fundus photographs. A computer system has been developed using image processing and pattern recognition techniques to detect early lesions of diabetic retinopathy (hemorrhages and microaneurysms, hard exudates, and cotton-wool spots). Color fundus photographs obtained from American Indians in Oklahoma were used in developing and testing the system. A set of 369 color fundus slides were used to train the computer system using 3 diagnostic categories: lesions present, questionable, or absent (Y/Q/N). A different set of 428 slides were used to test and evaluate the system, and its diagnostic results were compared with those of 2 human experts-the grader at the University of Wisconsin Fundus Photograph Reading Center (Madison) and a general ophthalmologist. The experiments included comparisons using 3 (Y/Q/N) and 2 diagnostic categories (Y/N) (questionable cases excluded in the latter). In the training phase, the agreement rates, sensitivity, and specificity in detecting the 3 lesions between the retinal specialist and the computer system were all above 90%. The kappa statistics were high (0.75-0.97), indicating excellent agreement between the specialist and the computer system. In the testing phase, the results obtained between the computer system and human experts were consistent with those of the training phase, and they were comparable with those between the human experts. The performance of the computer vision system in diagnosing early retinal lesions was comparable with that of human experts. Therefore, this mobile, electronically easily accessible, and noninvasive computer system, could become a mass screening tool and a clinical aid in diagnosing early lesions of diabetic retinopathy.

18F-positron-emitting/fluorescent labeled erythrocytes allow imaging of internal hemorrhage in a murine intracranial hemorrhage model

PubMed Central

Wang, Ye; An, Fei-Fei; Chan, Mark; Friedman, Beth; Rodriguez, Erik A; Tsien, Roger Y; Aras, Omer

2017-01-01

An agent for visualizing cells by positron emission tomography is described and used to label red blood cells. The labeled red blood cells are injected systemically so that intracranial hemorrhage can be visualized by positron emission tomography (PET). Red blood cells are labeled with 0.3 µg of a positron-emitting, fluorescent multimodal imaging probe, and used to non-invasively image cryolesion induced intracranial hemorrhage in a murine model (BALB/c, 2.36 × 108 cells, 100 µCi, <4 mm hemorrhage). Intracranial hemorrhage is confirmed by histology, fluorescence, bright-field, and PET ex vivo imaging. The low required activity, minimal mass, and high resolution of this technique make this strategy an attractive alternative for imaging intracranial hemorrhage. PET is one solution to a spectrum of issues that complicate single photon emission computed tomography (SPECT). For this reason, this application serves as a PET alternative to [99mTc]-agents, and SPECT technology that is used in 2 million annual medical procedures. PET contrast is also superior to gadolinium and iodide contrast angiography for its lack of clinical contraindications. PMID:28054494

Unilateral retinitis pigmentosa and cone-rod dystrophy

PubMed Central

Farrell, Donald F

2009-01-01

Purpose: The purpose of this paper is to report 14 new cases of unilateral retinitis pigmentosa and three new cases of cone-rod dystrophy and to compare the similarities and dissimilarities to those found in the bilateral forms of these disorders. Methods: A total of 272 cases of retinitis pigmentosa and 167 cases of cone-rod dystrophy were studied by corneal full field electroretinograms and electrooculograms. The student t-test was used to compare categories. Results: The percentage of familial and nonfamilial cases was the same for the bilateral and unilateral forms of the disease. In our series, unilateral retinitis pigmentosa makes up approximately 5% of the total population of retinitis pigmentosa, while unilateral cone-rod dystrophy makes up only about 2% of the total. In the familial forms of unilateral retinitis pigmentosa the most common inheritance pattern was autosomal dominant and all affected relatives had bilateral disease. Conclusion: Unilateral retinitis pigmentosa and cone-rod dystrophy appear to be directly related to the more common bilateral forms of these disorders. The genetic mechanisms which account for asymmetric disorders are not currently understood. It may be a different unidentified mutation at a single loci or it is possible that nonlinked mutations in multiple loci account for this unusual disorder. PMID:19668577

Retinal iron homeostasis in health and disease

PubMed Central

Song, Delu; Dunaief, Joshua L.

2013-01-01

Iron is essential for life, but excess iron can be toxic. As a potent free radical creator, iron generates hydroxyl radicals leading to significant oxidative stress. Since iron is not excreted from the body, it accumulates with age in tissues, including the retina, predisposing to age-related oxidative insult. Both hereditary and acquired retinal diseases are associated with increased iron levels. For example, retinal degenerations have been found in hereditary iron overload disorders, like aceruloplasminemia, Friedreich's ataxia, and pantothenate kinase-associated neurodegeneration. Similarly, mice with targeted mutation of the iron exporter ceruloplasmin and its homolog hephaestin showed age-related retinal iron accumulation and retinal degeneration with features resembling human age-related macular degeneration (AMD). Post mortem AMD eyes have increased levels of iron in retina compared to age-matched healthy donors. Iron accumulation in AMD is likely to result, in part, from inflammation, hypoxia, and oxidative stress, all of which can cause iron dysregulation. Fortunately, it has been demonstrated by in vitro and in vivo studies that iron in the retinal pigment epithelium (RPE) and retina is chelatable. Iron chelation protects photoreceptors and retinal pigment epithelial cells (RPE) in a variety of mouse models. This has therapeutic potential for diminishing iron-induced oxidative damage to prevent or treat AMD. PMID:23825457

Obstructive Sleep Apnea: An Unusual Cause of Hemorrhagic Stroke.

PubMed

Pawar, Nilesh H; O'Riordan, Jennifer A; Malik, Preeti; Vasanwala, Farhad F

2017-09-27

Stroke is one of the most common causes of mortality and morbidity worldwide. Hemorrhagic stroke comprises 10-20% of strokes. Here, we present a case report of hemorrhagic stroke that may have been secondary to untreated Obstructive Sleep Apnea (OSA) in a young man with no other cardiovascular risk factors or features of metabolic syndrome. A 32-year-old man was admitted for hemorrhagic stroke. An initial thorough workup for the etiology of stroke was inconclusive. Eventually, a polysomnography was done, which demonstrated OSA suggesting that untreated OSA may have contributed to his stroke. OSA may cause hemorrhagic stroke by nocturnal blood pressure surge. So, all physicians should consider doing polysomnography for unexplained hemorrhagic stroke or in patients at risk. Diagnosing and treating OSA would be critical in preventing hemorrhagic stroke and its recurrences.

Intranasal Fentanyl Intoxication Leading to Diffuse Alveolar Hemorrhage.

PubMed

Ruzycki, Shannon; Yarema, Mark; Dunham, Michael; Sadrzadeh, Hossein; Tremblay, Alain

2016-06-01

Increasing rates of opioid abuse, particularly fentanyl, may lead to more presentations of unusual effects of opioid toxicity. Diffuse alveolar hemorrhage is a rare complication of fentanyl overdose. A 45-year-old male presented in hypoxic respiratory failure secondary to diffuse alveolar hemorrhage requiring intubation. Comprehensive drug screening detected fentanyl without exposure to cocaine. Further history upon the patient's recovery revealed exposure to snorted fentanyl powder immediately prior to presentation. Diffuse alveolar hemorrhage is a potential, though rare, presentation of opioid intoxication. Recognition of less common complications of opioid abuse such as diffuse alveolar hemorrhage is important in proper management of overdoses.

Towards a Completely Implantable, Light-Sensitive Intraocular Retinal Prosthesis

DTIC Science & Technology

2001-10-25

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

Postconditioning with inhaled hydrogen promotes survival of retinal ganglion cells in a rat model of retinal ischemia/reperfusion injury.

PubMed

Wang, Ruobing; Wu, Jiangchun; Chen, Zeli; Xia, Fangzhou; Sun, Qinglei; Liu, Lin

2016-02-01

Retinal ischemia/reperfusion (I/R) injury plays a crucial role in the pathophysiology of various ocular diseases. Intraperitoneal injection or ocular instillation with hydrogen (H2)-rich saline was recently shown to be neuroprotective in the retina due to its anti-oxidative and anti-inflammatory effects. Our study aims to explore whether postconditioning with inhaled H2 can protect retinal ganglion cells (RGCs) in a rat model of retinal I/R injury. Retinal I/R injury was performed on the right eyes of rats and was followed by inhalation of 67% H2 mixed with 33% oxygen immediately after ischemia for 1h daily for one week. RGC density was counted using haematoxylin and eosin (HE) staining and retrograde labeling with cholera toxin beta (CTB). Visual function was assessed using flash visual evoked potentials (FVEP) and pupillary light reflex (PLR). Potential biomarkers of retinal oxidative stress and inflammatory responses were measured, including the expression of 4-Hydroxynonenalv (4-HNE), interleukin-1 beta (IL1-β) and tumor necrosis factor alpha (TNF-α). HE and CTB tracing showed that the survival rate of RGCs in the H2-treated group was significantly higher than the rate in the I/R group. Rats with H2 inhalation showed better visual function in assessments of FVEP and PLR. Moreover, H2 treatment significantly decreased the number of 4-HNE-stained cells in the ganglion cell layer and inhibited the retinal overexpression of IL1-β and TNF-α that was induced by retinal I/R injury. Our results demonstrate that postconditioning with inhaled high-dose H2 appears to confer neuroprotection against retinal I/R injury via anti-oxidative, anti-inflammatory and anti-apoptosis pathways. Copyright © 2015 Elsevier B.V. All rights reserved.

Retinal vascular changes are a marker for cerebral vascular diseases

PubMed Central

Moss, Heather E.

2016-01-01

The retinal circulation is a potential marker of cerebral vascular disease because it shares origin and drainage with the intracranial circulation and because it can be directly visualized using ophthalmoscopy. Cross sectional and cohort studies have demonstrated associations between chronic retinal and cerebral vascular disease, acute retinal and cerebral vascular disease and chronic retinal vascular disease and acute cerebral vascular disease. In particular, certain qualitative features of retinopathy, retinal artery occlusion and increased retinal vein caliber are associated with concurrent and future cerebrovascular events. These associations persist after accounting for confounding variables known to be disease-causing in both circulations, which supports the potential use of retinal vasculature findings to stratify individuals with regards to cerebral vascular disease risk. PMID:26008809

Recurrent hemorrhage in hemangioblastoma involving the posterior fossa: Case report

PubMed Central

Marvin, Eric; Akhter, Asad S.; Coppens, Jeroen R.

2017-01-01

Background: Hemangioblastomas (HGBs) are the most common primary intra-axial posterior fossa tumor in adults. Although spontaneous hemorrhage of these tumors is exceedingly rare, despite their vascular nature, we describe a case of recurrent hemorrhage with associated tonsillar herniation, and demonstrate that a surgical approach can provide a suitable outcome. Case Description: A 54-year-old female with von Hippel-Lindau (VHL) syndrome presented with acute loss of consciousness and Glasgow Coma Scale (GCS) was 4. Computed tomographic (CT) images demonstrated large volume subarachnoid hemorrhage of the posterior fossa with intraventricular extension and intraparenchymal hemorrhage involving the right cerebellar tonsil. Magnetic resonance imaging (MRI) displayed three lesions in the posterior fossa, two near the hemorrhage site. Patient underwent suboccipital craniectomy with a decent recovery followed by radiosurgery as she refused resection. A second hemorrhage occurred ultimately prompting surgical resection of the three posterior fossa lesions, with a reasonable postoperative course. Conclusion: Hemorrhage of HGBs of the posterior fossa can present in conjunction of tonsillar herniation. Re-hemorrhage appears to be likely if prior acute hemorrhage has occurred. A stepwise approach of surgical decompression and resection may provide the best outcome. PMID:28713626

Mechanism by which Untwisting of Retinal Leads to Productive Bacteriorhodopsin Photocycle States

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

Wolter, Tino; Elstner, Marcus; Fischer, Stefan

2014-01-01

Relaxation of the twisted-retinal photoproduct state triggers proton-coupled reaction cycle in retinal proteins. A key open question is whether the retinal relaxation path is governed by the intrinsic torsional properties of the retinal or rather by the interactions of the retinal with protein and water groups, given the crowded protein environments in which the retinal resides. We address this question by performing systematic quantum mechanical/molecular mechanical molecular dynamics computations of retinal dynamics in bacteriorhodopsin at different temperatures, reaction path computations, and assessment of the vibrational fingerprints of the retinal molecule. Our results demonstrate a complex dependence of the retinal dynamicsmore » and preferred geometry on temperature. As the temperature increases, the retinal dihedral angle samples values largely determined by its internal conformational energy. The protein environment shapes the energetics of retinal relaxation and provides hydrogen-bonding partners that stabilize the retinal geometry.« less

Coats-like retinitis pigmentosa: Reports of three cases

PubMed Central

Kan, Emrah; Yilmaz, Turgut; Aydemir, Orhan; Güler, Mete; Kurt, Jülide

2007-01-01

Purpose: Describing the ophthalmic findings of an exudative vasculopathy called as Coats-like retinitis pigmentosa on three patients. The etiology of the Coats-like retinitis pigmentosa is obscure. The principal theories have been discussed in this article. Methods: Three observational case series have been discussed. Complete ophthalmic examinations and color fundus photos, visual field, and fluorescein angiography have been performed. Results: We have identified 3 patients who have some typical clinical features of Coats-like retinitis pigmentosa; peripheral serous retinal detachment, telangiectasia, prominent lipid deposition, pigmentary changes in peripheral retina, and loss of vision. None of the three patients had positive family history. All of the patients have had symptoms of nyctalopia, decreased central vision, and two of them have had constriction of visual field. All of the patients have had cataracts and two of them underwent cataract surgery. Fundus examination and fluorescein angiography of patients revealed typical retinitis pigmentosa with Coats-type changes in bilateral inferiotemporal quadrants. Conclusion: A better understanding of clinical features and genetic etiology of Coats-type retinitis pigmentosa will aid diagnosis and development of new therapies. If sufficient conditions arise, genetic factors that influence the expression of CRB1 mutations in Coats-like retinitis pigmentosa should be detected. PMID:19668510

Retinal oxygen saturation before and after glaucoma surgery.

PubMed

Nitta, Eri; Hirooka, Kazuyuki; Shimazaki, Takeru; Sato, Shino; Ukegawa, Kaori; Nakano, Yuki; Tsujikawa, Akitaka

2017-08-01

This study compared retinal vessel oxygen saturation before and after glaucoma surgery. Retinal oxygen saturation in glaucoma patients was measured using a non-invasive spectrophotometric retinal oximeter. Adequate image quality was found in 49 of the 108 consecutive glaucoma patients recruited, with 30 undergoing trabeculectomy, 11 EX-PRESS and eight trabeculotomy. Retinal oxygen saturation measurements in the retinal arterioles and venules were performed at 1 day prior to and at approximately 10 days after surgery. Statistical analysis was performed using a Student's t-test. After glaucoma surgery, intraocular pressure (IOP) decreased from 19.8 ± 7.7 mmHg to 9.0 ± 5.7 mmHg (p < 0.001). Although oxygen saturation in retinal arterioles remained unchanged before and after surgery (104.7 ± 10.6% before and 105.4 ± 9.3% after surgery, p = 0.58), the oxygen saturation in the venules increased from 54.9 ± 7.4% to 57.4 ± 5.7% (p = 0.01). Intraocular pressure (IOP) decreases caused by glaucoma surgery had an effect on the retinal venous oxygen saturation. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Probabilistic retinal vessel segmentation

NASA Astrophysics Data System (ADS)

Wu, Chang-Hua; Agam, Gady

2007-03-01

Optic fundus assessment is widely used for diagnosing vascular and non-vascular pathology. Inspection of the retinal vasculature may reveal hypertension, diabetes, arteriosclerosis, cardiovascular disease and stroke. Due to various imaging conditions retinal images may be degraded. Consequently, the enhancement of such images and vessels in them is an important task with direct clinical applications. We propose a novel technique for vessel enhancement in retinal images that is capable of enhancing vessel junctions in addition to linear vessel segments. This is an extension of vessel filters we have previously developed for vessel enhancement in thoracic CT scans. The proposed approach is based on probabilistic models which can discern vessels and junctions. Evaluation shows the proposed filter is better than several known techniques and is comparable to the state of the art when evaluated on a standard dataset. A ridge-based vessel tracking process is applied on the enhanced image to demonstrate the effectiveness of the enhancement filter.

Retinal Pigment Epithelium Culture;a Potential Source of Retinal Stem Cells

PubMed Central

Akrami, Hassan; Soheili, Zahra-Soheila; Khalooghi, Keynoush; Ahmadieh, Hamid; Rezaie-Kanavi, Mojgan; Samiei, Shahram; Davari, Malihe; Ghaderi, Shima; Sanie-Jahromi, Fatemeh

2009-01-01

Purpose To establish human retinal pigment epithelial (RPE) cell culture as a source for cell replacement therapy in ocular diseases. Methods Human cadaver globes were used to isolate RPE cells. Each globe was cut into several pieces of a few millimeters in size. After removing the sclera and choroid, remaining tissues were washed in phosphate buffer saline and RPE cells were isolated using dispase enzyme solution and cultured in Dulbecco’s Modified Eagle’s Medium: Nutrient Mixture F-12 supplemented with 10% fetal calf serum. Results Primary cultures of RPE cells were established and spheroid colonies related to progenitor/stem cells developed in a number of cultures. The colonies included purely pigmented or mixed pigmented and non-pigmented cells. After multiple cellular passages, several types of photoreceptors and neural-like cells were detected morphologically. Conclusion Cellular plasticity in RPE cell cultures revealed promising results in terms of generation of stem/progenitor cells from human RPE cells. Whether the spheroids and neural-like retinal cells were directly derived from retinal stem cells or offspring of trans-differentiating or de-differentiating RPE cells remains to be answered. PMID:23198062

Terson syndrome and leukemia: a case report

PubMed Central

Lorenzi, Umberto; Buschini, Elisa; Fea, Antonio; Machetta, Federica; Grignolo, Federico Maria

2014-01-01

Background Terson syndrome is defined as intraocular hemorrhage associated with intracranial bleeding. This syndrome can occur in the event of intracranial hemorrhage or elevated intracranial pressure. To our knowledge, it has never been associated with chronic myeloid leukemia. A 45-year-old woman suffering from chronic myeloid leukemia was referred to our clinic with Terson syndrome after intracranial bleeding. We followed this patient for a year, performing visual acuity assessment, fundus examination, color retinography, and A-scan and B-scan ultrasonography. At presentation, her best-corrected visual acuity on the right was 20/63 and on the left was 20/320. In the right eye, retinoscopy showed blurring of the optic margins surrounded by retinal and preretinal hemorrhages, preretinal fibrosis of the optic disc along the vascular arcades, and perivascular retinal infiltrates. In the left eye, the optic disc was surrounded by retinal and preretinal hemorrhages, and massive fibrosis with hard exudates and severe preretinal hemorrhage were observed at the posterior pole. Roth spots and many circular hemorrhages were noted at the periphery of the retina. A-scan and B-scan ultrasonography did not show intraocular leukemic infiltration. The clinical picture remained stable over the following 12 months. In this patient, we observed the ophthalmoscopic features of chronic myeloid leukemia, but also coexistence of features typical of Terson syndrome. To our knowledge, no similar cases have been reported previously. PMID:24729684

Clinical applications of retinal gene therapy.

PubMed

Lipinski, Daniel M; Thake, Miriam; MacLaren, Robert E

2013-01-01

Many currently incurable forms of blindness affecting the retina have a genetic etiology and several others, such as those resulting from retinal vascular disturbances, respond to repeated, potentially indefinite administration of molecular based treatments. The recent clinical advances in retinal gene therapy have shown that viral vectors can deliver genes safely to the retina and the promising initial results from a number of clinical trials suggest that certain diseases may potentially be treatable. Gene therapy provides a means of expressing proteins within directly transduced cells with far greater efficacy than might be achieved by traditional systemic pharmacological approaches. Recent developments have demonstrated how vector gene expression may be regulated and further improvements to vector design have limited side effects and improved safety profiles. These recent steps have been most significant in bringing gene therapy into the mainstream of ophthalmology. Nevertheless translating retinal gene therapy from animal research into clinical trials is still a lengthy process, including complexities in human retinal diseases that have been difficult to model in the laboratory. The focus of this review is to summarize the genetic background of the most common retinal diseases, highlight current concepts of gene delivery technology, and relate those technologies to pre-clinical and clinical gene therapy studies. Copyright © 2012 Elsevier Ltd. All rights reserved.

Stem Cell Therapies in Retinal Disorders.

PubMed

Garg, Aakriti; Yang, Jin; Lee, Winston; Tsang, Stephen H

2017-02-02

Stem cell therapy has long been considered a promising mode of treatment for retinal conditions. While human embryonic stem cells (ESCs) have provided the precedent for regenerative medicine, the development of induced pluripotent stem cells (iPSCs) revolutionized this field. iPSCs allow for the development of many types of retinal cells, including those of the retinal pigment epithelium, photoreceptors, and ganglion cells, and can model polygenic diseases such as age-related macular degeneration. Cellular programming and reprogramming technology is especially useful in retinal diseases, as it allows for the study of living cells that have genetic variants that are specific to patients' diseases. Since iPSCs are a self-renewing resource, scientists can experiment with an unlimited number of pluripotent cells to perfect the process of targeted differentiation, transplantation, and more, for personalized medicine. Challenges in the use of stem cells are present from the scientific, ethical, and political realms. These include transplant complications leading to anatomically incorrect placement, concern for tumorigenesis, and incomplete targeting of differentiation leading to contamination by different types of cells. Despite these limitations, human ESCs and iPSCs specific to individual patients can revolutionize the study of retinal disease and may be effective therapies for conditions currently considered incurable.

Deblurring adaptive optics retinal images using deep convolutional neural networks.

PubMed

Fei, Xiao; Zhao, Junlei; Zhao, Haoxin; Yun, Dai; Zhang, Yudong

2017-12-01

The adaptive optics (AO) can be used to compensate for ocular aberrations to achieve near diffraction limited high-resolution retinal images. However, many factors such as the limited aberration measurement and correction accuracy with AO, intraocular scatter, imaging noise and so on will degrade the quality of retinal images. Image post processing is an indispensable and economical method to make up for the limitation of AO retinal imaging procedure. In this paper, we proposed a deep learning method to restore the degraded retinal images for the first time. The method directly learned an end-to-end mapping between the blurred and restored retinal images. The mapping was represented as a deep convolutional neural network that was trained to output high-quality images directly from blurry inputs without any preprocessing. This network was validated on synthetically generated retinal images as well as real AO retinal images. The assessment of the restored retinal images demonstrated that the image quality had been significantly improved.

Deblurring adaptive optics retinal images using deep convolutional neural networks

PubMed Central

Fei, Xiao; Zhao, Junlei; Zhao, Haoxin; Yun, Dai; Zhang, Yudong

2017-01-01

The adaptive optics (AO) can be used to compensate for ocular aberrations to achieve near diffraction limited high-resolution retinal images. However, many factors such as the limited aberration measurement and correction accuracy with AO, intraocular scatter, imaging noise and so on will degrade the quality of retinal images. Image post processing is an indispensable and economical method to make up for the limitation of AO retinal imaging procedure. In this paper, we proposed a deep learning method to restore the degraded retinal images for the first time. The method directly learned an end-to-end mapping between the blurred and restored retinal images. The mapping was represented as a deep convolutional neural network that was trained to output high-quality images directly from blurry inputs without any preprocessing. This network was validated on synthetically generated retinal images as well as real AO retinal images. The assessment of the restored retinal images demonstrated that the image quality had been significantly improved. PMID:29296496

Spectrally optimal illuminations for diabetic retinopathy detection in retinal imaging

NASA Astrophysics Data System (ADS)

Bartczak, Piotr; Fält, Pauli; Penttinen, Niko; Ylitepsa, Pasi; Laaksonen, Lauri; Lensu, Lasse; Hauta-Kasari, Markku; Uusitalo, Hannu

2017-04-01

Retinal photography is a standard method for recording retinal diseases for subsequent analysis and diagnosis. However, the currently used white light or red-free retinal imaging does not necessarily provide the best possible visibility of different types of retinal lesions, important when developing diagnostic tools for handheld devices, such as smartphones. Using specifically designed illumination, the visibility and contrast of retinal lesions could be improved. In this study, spectrally optimal illuminations for diabetic retinopathy lesion visualization are implemented using a spectrally tunable light source based on digital micromirror device. The applicability of this method was tested in vivo by taking retinal monochrome images from the eyes of five diabetic volunteers and two non-diabetic control subjects. For comparison to existing methods, we evaluated the contrast of retinal images taken with our method and red-free illumination. The preliminary results show that the use of optimal illuminations improved the contrast of diabetic lesions in retinal images by 30-70%, compared to the traditional red-free illumination imaging.

Intracranial pressure after subarachnoid hemorrhage.

PubMed

Zoerle, Tommaso; Lombardo, Alessandra; Colombo, Angelo; Longhi, Luca; Zanier, Elisa R; Rampini, Paolo; Stocchetti, Nino

2015-01-01

To describe mean intracranial pressure after aneurysmal subarachnoid hemorrhage, to identify clinical factors associated with increased mean intracranial pressure, and to explore the relationship between mean intracranial pressure and outcome. Analysis of a prospectively collected observational database. Neuroscience ICU of an academic hospital. One hundred sixteen patients with subarachnoid hemorrhage and intracranial pressure monitoring. None. Episodes of intracranial pressure greater than 20 mm Hg lasting at least 5 minutes and the mean intracranial pressure for every 12-hour interval were analyzed. The highest mean intracranial pressure was analyzed in relation to demographic characteristics, acute neurologic status, initial radiological findings, aneurysm treatment, clinical vasospasm, and ischemic lesion. Mortality and 6-month outcome (evaluated using a dichotomized Glasgow Outcome Scale) were also introduced in multivariable logistic models. Eighty-one percent of patients had at least one episode of high intracranial pressure and 36% had a highest mean intracranial pressure more than 20 mm Hg. The number of patients with high intracranial pressure peaked 3 days after subarachnoid hemorrhage and declined after day 7. Highest mean intracranial pressure greater than 20 mm Hg was significantly associated with initial neurologic status, aneurysmal rebleeding, amount of blood on CT scan, and ischemic lesion within 72 hours from subarachnoid hemorrhage. Patients with highest mean intracranial pressure greater than 20 mm Hg had significantly higher mortality. When death, vegetative state, and severe disability at 6 months were pooled, however, intracranial pressure was not an independent predictor of unfavorable outcome. High intracranial pressure is a common complication in the first week after subarachnoid hemorrhage in severe cases admitted to ICU. Mean intracranial pressure is associated with the severity of early brain injury and with mortality.

STRUCTURAL ASSESSMENT OF HYPERAUTOFLUORESCENT RING IN PATIENTS WITH RETINITIS PIGMENTOSA

PubMed Central

LIMA, LUIZ H.; CELLA, WENER; GREENSTEIN, VIVIENNE C.; WANG, NAN-KAI; BUSUIOC, MIHAI; THEODORE SMITH, R.; YANNUZZI, LAWRENCE A.; TSANG, STEPHEN H.

2009-01-01

Purpose To analyze the retinal structure underlying the hyperautofluorescent ring visible on fundus autofluorescence in patients with retinitis pigmentosa. Methods Twenty-four eyes of 13 patients with retinitis pigmentosa, aged 13 years to 67 years, were studied. The integrity of the photoreceptor cilia, also known as the inner/outer segment junction of the photoreceptors, the outer nuclear layer, and retinal pigment epithelium, was evaluated outside, across, and inside the ring with spectral-domain optical coherence tomography (OCT). Results Inside the foveal area, fundus autofluorescence did not detect abnormalities. Outside the ring, fundus autofluorescence revealed hypoautofluorescence compatible with the photoreceptor/retinal pigment epithelium degeneration. Spectral-domain OCT inside the ring, in the area of normal foveal fundus autofluorescence, revealed an intact retinal structure in all eyes and total retinal thickness values that were within normal limits. Across the ring, inner/outer segment junction disruption was observed and the outer nuclear layer was decreased in thickness in a centrifugal direction in all eyes. Outside the hyperautofluorescent ring, the inner/outer segment junction and the outer nuclear layer appeared to be absent and there were signs of retinal pigment epithelium degeneration. Conclusion Disruption of the inner/outer segment junction and a decrease in outer retinal thickness were found across the central hyperautofluorescent ring seen in retinitis pigmentosa. Outer segment phagocytosis by retinal pigment epithelium is necessary for the formation of an hyperautofluorescent ring. PMID:19584660

Pressor and hemodilution responses compensate for acute hemorrhage in bluefish.

PubMed

Ogilvy, C S; Tremml, P G; DuBois, A B

1988-01-01

1. After hemorrhage of 21% blood volume (0.9% body weight) blood pressure (BP) and heart rate (H.R.) of unanesthetized bluefish (Pomatomus saltatrix) recovered within 5 min. 2. Phentolamine blocked this recovery. 3. Atropine increased control H.R. from 48 to 87 per min, and to 108 after hemorrhage, with delay of BP recovery to 10 min. 4. With small, repeated hemorrhages every 20 min, hemodilution and recovery of BP occurred between hemorrhages. Removal of 27% blood volume resulted in only temporary recovery. 5. Thirty min after hemorrhage, plasma epinephrine was 5 x and norepinephrine 8 x control. 6. Thus, bluefish tolerate hemorrhage with initial vasoconstriction via alpha-adrenergic pathways, and hemodilution.

The Edge Detectors Suitable for Retinal OCT Image Segmentation

PubMed Central

Yang, Jing; Gao, Qian; Zhou, Sheng

2017-01-01

Retinal layer thickness measurement offers important information for reliable diagnosis of retinal diseases and for the evaluation of disease development and medical treatment responses. This task critically depends on the accurate edge detection of the retinal layers in OCT images. Here, we intended to search for the most suitable edge detectors for the retinal OCT image segmentation task. The three most promising edge detection algorithms were identified in the related literature: Canny edge detector, the two-pass method, and the EdgeFlow technique. The quantitative evaluation results show that the two-pass method outperforms consistently the Canny detector and the EdgeFlow technique in delineating the retinal layer boundaries in the OCT images. In addition, the mean localization deviation metrics show that the two-pass method caused the smallest edge shifting problem. These findings suggest that the two-pass method is the best among the three algorithms for detecting retinal layer boundaries. The overall better performance of Canny and two-pass methods over EdgeFlow technique implies that the OCT images contain more intensity gradient information than texture changes along the retinal layer boundaries. The results will guide our future efforts in the quantitative analysis of retinal OCT images for the effective use of OCT technologies in the field of ophthalmology. PMID:29065594

Stem cell therapy for retinal diseases

PubMed Central

Garcia, José Mauricio; Mendonça, Luisa; Brant, Rodrigo; Abud, Murilo; Regatieri, Caio; Diniz, Bruno

2015-01-01

In this review, we discuss about current knowledge about stem cell (SC) therapy in the treatment of retinal degeneration. Both human embryonic stem cell and induced pluripotent stem cell has been growth in culture for a long time, and started to be explored in the treatment of blinding conditions. The Food and Drug Administration, recently, has granted clinical trials using SC retinal therapy to treat complex disorders, as Stargardt’s dystrophy, and patients with geographic atrophy, providing good outcomes. This study’s intent is to overview the critical regeneration of the subretinal anatomy through retinal pigment epithelium transplantation, with the goal of reestablish important pathways from the retina to the occipital cortex of the brain, as well as the differentiation from pluripotent quiescent SC to adult retina, and its relationship with a primary retinal injury, different techniques of transplantation, management of immune rejection and tumorigenicity, its potential application in improving patients’ vision, and, finally, approaching future directions and challenges for the treatment of several conditions. PMID:25621115

Ultra-Widefield Steering-Based SD-OCT Imaging of the Retinal Periphery

PubMed Central

Choudhry, Netan; Golding, John; Manry, Matthew W.; Rao, Rajesh C.

2016-01-01

Objective To describe the spectral-domain optical coherence tomography (SD-OCT) features of peripheral retinal findings using an ultra-widefield (UWF) steering technique to image the retinal periphery. Design Observational study. Participants 68 patients (68 eyes) with 19 peripheral retinal features. Main Outcome Measures SD-OCT-based structural features. Methods Nineteen peripheral retinal features including: vortex vein, congenital hypertrophy of the retinal pigment epithelium (CHRPE), pars plana, ora serrata pearl, typical cystoid degeneration (TCD), cystic retinal tuft, meridional fold, lattice and cobblestone degeneration, retinal hole, retinal tear, rhegmatogenous retinal detachment (RRD), typical degenerative senile retinoschisis, peripheral laser coagulation scars, ora tooth, cryopexy scars (retinal tear and treated retinoblastoma scar), bone spicules, white without pressure, and peripheral drusen were identified by peripheral clinical examination. Near infrared (NIR) scanning laser ophthalmoscopy (SLO) images and SD-OCT of these entities were registered to UWF color photographs. Results SD-OCT resolved structural features of all peripheral findings. Dilated hyporeflective tubular structures within the choroid were observed in the vortex vein. Loss of retinal lamination, neural retinal attenuation, RPE loss or hypertrophy were seen in several entities including CHRPE, ora serrata pearl, TCD, cystic retinal tuft, meridional fold, lattice and cobblestone degenerations. Hyporeflective intraretinal spaces, indicating cystoid or schitic fluid, were seen in ora serrata pearl, ora tooth, TCD, cystic retinal tuft, meridional fold, retinal hole, and typical degenerative senile retinoschisis. The vitreoretinal interface, which often consisted of lamellae-like structures of the condensed cortical vitreous near or adherent to the neural retina, appeared clearly in most peripheral findings, confirming its association with many low-risk and vision-threatening pathologies

Nitric oxide regulates retinal vascular tone in humans.

PubMed

Dorner, Guido T; Garhofer, Gerhard; Kiss, Barbara; Polska, Elzbieta; Polak, Kaija; Riva, Charles E; Schmetterer, Leopold

2003-08-01

The purpose of the present study was to investigate the contribution of basal nitric oxide (NO) on retinal vascular tone in humans. In addition, we set out to elucidate the role of NO in flicker-induced retinal vasodilation in humans. Twelve healthy young subjects were studied in a three-way crossover design. Subjects received an intravenous infusion of either placebo or NG-monomethyl-L-arginine (L-NMMA; 3 or 6 mg/kg over 5 min), an inhibitor of NO synthase. Thereafter, diffuse luminance flicker was consecutively performed for 16, 32, and 64 s at a frequency of 8 Hz. The effect of L-NMMA on retinal arterial and venous diameter was assessed under resting conditions and during the hyperemic flicker response. Retinal vessel diameter was measured with a Zeiss retinal vessel analyzer. L-NMMA significantly reduced arterial diameter (3 mg/kg: -2%; 6 mg/kg: -4%, P < 0.001) and venous diameter (3 mg/kg: -5%; 6 mg/kg: -8%, P < 0.001). After placebo infusion, flicker induced a significant increase in retinal vessel diameter (P < 0.001). At a flicker duration of 64 s, arterial diameter increased by 4% and venous diameter increased by 3%. L-NMMA did not abolish these hyperemic responses but blunted venous vasodilation (P = 0.017) and arterial vasodilation (P = 0.02) in response to flicker stimulation. Our data indicate that NO contributes to basal retinal vascular tone in humans. In addition, NO appears to play a role in flicker-induced vasodilation of the human retinal vasculature.

Glibenclamide for the treatment of ischemic and hemorrhagic stroke.

PubMed

Caffes, Nicholas; Kurland, David B; Gerzanich, Volodymyr; Simard, J Marc

2015-03-04

Ischemic and hemorrhagic strokes are associated with severe functional disability and high mortality. Except for recombinant tissue plasminogen activator, therapies targeting the underlying pathophysiology of central nervous system (CNS) ischemia and hemorrhage are strikingly lacking. Sur1-regulated channels play essential roles in necrotic cell death and cerebral edema following ischemic insults, and in neuroinflammation after hemorrhagic injuries. Inhibiting endothelial, neuronal, astrocytic and oligodendroglial sulfonylurea receptor 1-transient receptor potential melastatin 4 (Sur1-Trpm4) channels and, in some cases, microglial KATP (Sur1-Kir6.2) channels, with glibenclamide is protective in a variety of contexts. Robust preclinical studies have shown that glibenclamide and other sulfonylurea agents reduce infarct volumes, edema and hemorrhagic conversion, and improve outcomes in rodent models of ischemic stroke. Retrospective studies suggest that diabetic patients on sulfonylurea drugs at stroke presentation fare better if they continue on drug. Additional laboratory investigations have implicated Sur1 in the pathophysiology of hemorrhagic CNS insults. In clinically relevant models of subarachnoid hemorrhage, glibenclamide reduces adverse neuroinflammatory and behavioral outcomes. Here, we provide an overview of the preclinical studies of glibenclamide therapy for CNS ischemia and hemorrhage, discuss the available data from clinical investigations, and conclude with promising preclinical results that suggest glibenclamide may be an effective therapeutic option for ischemic and hemorrhagic stroke.

Retinal image quality during accommodation.

PubMed

López-Gil, Norberto; Martin, Jesson; Liu, Tao; Bradley, Arthur; Díaz-Muñoz, David; Thibos, Larry N

2013-07-01

We asked if retinal image quality is maximum during accommodation, or sub-optimal due to accommodative error, when subjects perform an acuity task. Subjects viewed a monochromatic (552 nm), high-contrast letter target placed at various viewing distances. Wavefront aberrations of the accommodating eye were measured near the endpoint of an acuity staircase paradigm. Refractive state, defined as the optimum target vergence for maximising retinal image quality, was computed by through-focus wavefront analysis to find the power of the virtual correcting lens that maximizes visual Strehl ratio. Despite changes in ocular aberrations and pupil size during binocular viewing, retinal image quality and visual acuity typically remain high for all target vergences. When accommodative errors lead to sub-optimal retinal image quality, acuity and measured image quality both decline. However, the effect of accommodation errors of on visual acuity are mitigated by pupillary constriction associated with accommodation and binocular convergence and also to binocular summation of dissimilar retinal image blur. Under monocular viewing conditions some subjects displayed significant accommodative lag that reduced visual performance, an effect that was exacerbated by pharmacological dilation of the pupil. Spurious measurement of accommodative error can be avoided when the image quality metric used to determine refractive state is compatible with the focusing criteria used by the visual system to control accommodation. Real focusing errors of the accommodating eye do not necessarily produce a reliably measurable loss of image quality or clinically significant loss of visual performance, probably because of increased depth-of-focus due to pupil constriction. When retinal image quality is close to maximum achievable (given the eye's higher-order aberrations), acuity is also near maximum. A combination of accommodative lag, reduced image quality, and reduced visual function may be a useful

Influence of Bleeding Pattern on Ischemic Lesions After Spontaneous Hypertensive Intracerebral Hemorrhage with Intraventricular Hemorrhage.

PubMed

Rivera-Lara, Lucia; Murthy, Santosh B; Nekoovaght-Tak, Saman; Ali, Hasan; McBee, Nichol; Dlugash, Rachel; Ram, Malathi; Thompson, Richard; Awad, Issam A; Hanley, Daniel F; Ziai, Wendy C

2018-03-27

Concomitant acute ischemic lesions are detected in up to a quarter of patients with spontaneous intracerebral hemorrhage (ICH). Influence of bleeding pattern and intraventricular hemorrhage (IVH) on risk of ischemic lesions has not been investigated. Retrospective study of all 500 patients enrolled in the CLEAR III randomized controlled trial of thrombolytic removal of obstructive IVH using external ventricular drainage. The primary outcome measure was radiologically confirmed ischemic lesions, as reported by the Safety Event Committee and confirmed by two neurologists. We assessed predictors of ischemic lesions including analysis of bleeding patterns (ICH, IVH and subarachnoid hemorrhage) on computed tomography scans (CT). Secondary outcomes were blinded assessment of mortality and modified Rankin scale (mRS) at 30 and 180 days. Ischemic lesions occurred in 23 (4.6%) during first 30 days after ICH. Independent risk factors associated with ischemic lesions in logistic regression models adjusted for confounders were higher IVH volume (p = 0.004) and persistent subarachnoid hemorrhage on CT scan (p = 0.03). Patients with initial IVH volume ≥ 15 ml had five times the odds of concomitant ischemic lesions compared to IVH volume < 15 ml. Patients with ischemic lesions had significantly higher odds of death at 1 and 6 months (but not poor outcome; mRS 4-6) compared to patients without concurrent ischemic lesions. Occurrence of ischemic lesions in the acute phase of IVH is not uncommon and is significantly associated with increased early and late mortality. Extra-parenchymal blood (larger IVH and visible subarachnoid hemorrhage) is a strong predictor for development of concomitant ischemic lesions after ICH.

Risk factors for post-tonsillectomy hemorrhage.

PubMed

Ikoma, Ryo; Sakane, Sayaka; Niwa, Kazutomo; Kanetaka, Sayaka; Kawano, Toshiro; Oridate, Nobuhiko

2014-08-01

The aim of the present study was to investigate the rate of post-tonsillectomy hemorrhage (PTH) in a single institution and to evaluate the clinical risk factors for PTH. We reviewed the records of 692 patients who underwent tonsillectomy (TE) at Yokohama Minami Kyosai Hospital in Japan. PTH grades were grouped into three categories according to the severity of the hemorrhagic episode: (I) minimal hemorrhage that stopped after noninvasive treatment, (II) hemorrhage requiring treatment with local anesthesia, and (III) hemorrhage requiring reoperation under general anesthesia in the operating room. Clinical risk factors such as sex, age (adults vs. children), TE indication, surgeon's skill level, operative time, ligature type, and duration of antibiotic administration for PTH were investigated. Among the 692 patients, 80 (11.6%) showed PTH, with primary and secondary hemorrhage accounting for 1.6% and 10.0%, respectively. A category III PTH was observed in 18 patients; thus, the overall risk of reoperation was 2.6%. The PTH episode most frequently occurred on postoperative days 5 and 6. The frequency of PTH was significantly higher in male patients and in adults (P<0.01, for both factors). Surgeon's skill was also associated with PTH rate. A stepwise multivariate logistic regression revealed that adult age (odds ratio [OR]=18.9) and male gender (OR=3.78) were the clinical risk factors for PTH. It also revealed that male gender (OR=82065335), adult age (OR=10.6), and surgeon's skill level (OR=7.50) were the clinical risk factors for the category III PTH. The risk of PTH was higher in this report compared with previous reports, which may be associated with the definition of PTH. Clinical risk factors for PTH were adult age and male gender. The surgeon's skill level was an additional risk factor for category III PTH. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Educational Placement After Pediatric Intracerebral Hemorrhage.

PubMed

Hawks, Charlotte; Jordan, Lori C; Gindville, Melissa; Ichord, Rebecca N; Licht, Daniel J; Beslow, Lauren A

2016-08-01

This study describes educational placement of school-aged children after spontaneous intracerebral hemorrhage and examines whether educational placement is associated with severity of neurological deficits. Children with spontaneous intracerebral hemorrhage presenting from 2007 to 2013 were prospectively enrolled at three tertiary children's hospitals. The Pediatric Stroke Outcome Measure and parental interview gathered information about neurological outcome, school attendance, and educational placement. The cohort of 92 enrolled children included 42 school-aged children (6 to 17 years) with intracerebral hemorrhage. Four children died; one was excluded because of preexisting cognitive deficits. Thirty-seven children completed three-month follow-up, and 30 completed 12-month follow-up. At 12 months, 14 children (46.7%) received regular age-appropriate programming, 12 (40%) attended school with in-class services, three (10%) were in special education programs, and one child (3.3%) received home-based services because of intracerebral hemorrhage-related deficits. Of 30 children with three- and 12-month follow-up, 14 (46.7%) improved their education status, 13 (43.3%) remained at the same education level, and three (10%) began to receive in-class services. An increasing Pediatric Stroke Outcome Measure score predicted the need for educational modifications at three months (odds ratio, 3.3; 95% confidence interval, 1.4 to 7.9; P = 0.007) and at 12 months (odds ratio, 2.1; 95% confidence interval, 1.1 to 3.9; P = 0.025). Most children returned to school within a year after intracerebral hemorrhage, and many had a reduction in the intensity of educational support. However, a great need for educational services persisted at 12 months after intracerebral hemorrhage with fewer than half enrolled in regular age-appropriate classes. Worse deficits on the Pediatric Stroke Outcome Measure were associated with remedial educational placement. Copyright © 2016 Elsevier

The influence of retinal eye diseases on painting.

PubMed

Ivanišević, Petar; Ivanišević, Milan

2015-03-01

In this work the possible influences of some retinal eye problems on paintings of several famous artists are considered. The change of painting styles and artistic expression in different periods and ages in a group of world-wide well-known painters are described and correlated with known or suspected retinal diseases. Some of them largely became recognizable because of that. Contemplations are offered about the effects of retinal diseases in the works of Degas, Munch, Cézanne, O'Keeffe, Constable and Goya. Retinal eye diseases have a significant impact on the work of selected famous painters.

Strategy for the management of uncomplicated retinal detachments: the European vitreo-retinal society retinal detachment study report 1.

PubMed

Adelman, Ron A; Parnes, Aaron J; Ducournau, Didier

2013-09-01

To study success and failure in the treatment of uncomplicated rhegmatogenous retinal detachments (RRDs). Nonrandomized, multicenter retrospective study. One hundred seventy-six surgeons from 48 countries spanning 5 continents provided information on the primary procedures for 7678 cases of RRDs including 4179 patients with uncomplicated RRDs. Reported data included specific clinical findings, the method of repair, and the outcome after intervention. Final failure of retinal detachment repair (level 1 failure rate), remaining silicone oil at the study's conclusion (level 2 failure rate), and need for additional procedures to repair the detachment (level 3 failure rate). Four thousand one hundred seventy-nine uncomplicated cases of RRD were included. Combining phakic, pseudophakic, and aphakic groups, those treated with scleral buckle alone (n = 1341) had a significantly lower final failure rate than those treated with vitrectomy, with or without a supplemental buckle (n = 2723; P = 0.04). In phakic patients, final failure rate was lower in the scleral buckle group compared with those who had vitrectomy, with or without a supplemental buckle (P = 0.028). In pseudophakic patients, the failure rate of the initial procedure was lower in the vitrectomy group compared with the scleral buckle group (P = 3×10(-8)). There was no statistically significant difference in failure rate between segmental (n = 721) and encircling (n = 351) buckles (P = 0.5). Those who underwent vitrectomy with a supplemental scleral buckle (n = 488) had an increased failure rate compared with those who underwent vitrectomy alone (n = 2235; P = 0.048). Pneumatic retinopexy was found to be comparable with scleral buckle when a retinal hole was present (P = 0.65), but not in cases with a flap tear (P = 0.034). In the treatment of uncomplicated phakic retinal detachments, repair using scleral buckle may be a good option. There was no significant difference between segmental versus 360-degree buckle

Intraocular retinal prosthesis.

PubMed Central

Humayun, M S

2001-01-01

PURPOSE: An electronic implant that can bypass the damaged photoreceptors and electrically stimulate the remaining retinal neurons to restore useful vision has been proposed. A number of key questions remain to make this approach feasible. The goal of this thesis is to address the following 2 specific null hypotheses: (1) Stimulus parameters make no difference in the electrically elicited retinal responses. (2) Just as we have millions of photoreceptors, so it will take a device that can generate millions of pixels/light points to create useful vision. METHODS: For electrophysiologic experiments, 2 different setups were used. In the first setup, charge-balanced pulses were delivered to the retinal surface via electrodes inserted through an open sky approach in normal or blind retinal degenerate (rd) mice. In the second setup, the rabbit retina was removed under red light conditions from an enucleated eye and then maintained in a chamber while being superfused with oxygenated, heated Ames media. In both setups, stimulating electrodes and recording electrodes were positioned on the retinal surface to evaluate the effect of varying stimulation parameters on the orthodromic retinal responses (i.e., recording electrode placed between stimulating electrodes and optic nerve head). For psychophysical experiments, visual images were divided into pixels of light that could be projected in a pattern on the retina in up to 8 sighted volunteers. Subjects were asked to perform various tasks ranging from reading and face recognition to various activities of daily living. RESULTS: Electrophysiologic experiments: In a normal mouse, a single cycle of a 1-kHz sine wave was significantly more efficient than a 1-kHz square wave (P < .05), but no such difference was noted in either of the 8- or 16-week-old rd mouse groups (8-week-old, P = .426; 16-week-old, P = .078). Charge threshold was significantly higher in 16-week-old rd mouse versus both 8-week-old rd and normal mouse for every

Occult hemorrhage in children with severe ITP.

PubMed

Flores, Adolfo; Buchanan, George R

2016-03-01

Little is known about the frequency and significance of clinically unapparent or occult hemorrhage in ITP. Therefore, we prospectively explored the sites and frequency of occult bleeding in children with severe ITP at diagnosis or upon symptomatic relapse in a prospective, single-institution cohort study of patients ≤ 18 years of age and a platelet count ≤ 10,000/mm(3) . Data collected included bleeding severity assessment, urinalysis, fecal occult blood testing, and non-contrast brain MRI. Stool and urine samples were tested within 7 days of diagnosis or symptomatic relapse. Three months after diagnosis or relapse a noncontrast brain MRI evaluated hemosiderin deposits resulting from prior localized hemorrhage. Fifty-two ITP patients were enrolled with a mean platelet count of 4,000/mm(3) . A significant occurrence of occult hemorrhage was identified in the urine (27%) compared with clinically overt hematuria (0.91%, P < 0.0005). CNS microbleeding in the superficial cortex of the left frontal lobe was identified in one child with occult bleeding in the urinary tract. There was no relationship between occult hemorrhage and bleeding manifestations on physical examination. Occult hemorrhage was not a harbinger of subsequent bleeding. Our findings suggest that occult hemorrhage occurs with greater frequency than overt bleeding in children with severe ITP. CNS microbleeding is a potential risk in this patient population. Assessment of brain microbleeds and microscopic hematuria in this patient population require additional study. © 2015 Wiley Periodicals, Inc.

RI in central retinal artery as assessed by CDI does not correspond to retinal vascular resistance.

PubMed

Polska, E; Kircher, K; Ehrlich, P; Vecsei, P V; Schmetterer, L

2001-04-01

The aim of the present study was to investigate the association between ultrasound Doppler measurements of resistive index (RI) in the central retinal artery and retinal vascular resistance (R) assessed with laser Doppler velocimetry, vessel size measurement, and calculation of ocular perfusion pressure (PP) in healthy subjects. An increase in vascular resistance was induced by inhalation of 100% O(2). During hyperoxia no significant changes in PP were observed. Mean flow velocity in main retinal veins was reduced by -27.5 +/- 2.0%. The average decrease in diameter was -11.5 +/- 1.0%. R, which was calculated as the ratio of PP to flow rate, increased by 97.6 +/- 7.7%. RI increased as well, but the effect was much smaller (6.6 +/- 2.2%). In addition, a negative correlation was found between baseline values of R and RI (r = -0.83). During hyperoxia R and RI were not associated. In conclusion, our data indicate that RI as assessed with color Doppler imaging in the central retinal artery is not an adequate measure of R.

Visible-light OCT to quantify retinal oxygen metabolism (Conference Presentation)

NASA Astrophysics Data System (ADS)

Zhang, Hao F.; Yi, Ji; Chen, Siyu; Liu, Wenzhong; Soetikno, Brian T.

2016-03-01

We explored, both numerically and experimentally, whether OCT can be a good candidate to accurately measure retinal oxygen metabolism. We first used statistical methods to numerically simulate photon transport in the retina to mimic OCT working under different spectral ranges. Then we analyze accuracy of OCT oximetry subject to parameter variations such as vessel size, pigmentation, and oxygenation. We further developed an experimental OCT system based on the spectral range identified by our simulation work. We applied the newly developed OCT to measure both retinal hemoglobin oxygen saturation (sO2) and retinal retinal flow. After obtaining the retinal sO2 and blood velocity, we further measured retinal vessel diameter and calculated the retinal oxygen metabolism rate (MRO2). To test the capability of our OCT, we imaged wild-type Long-Evans rats ventilated with both normal air and air mixtures with various oxygen concentrations. Our simulation suggested that OCT working within visible spectral range is able to provide accurate measurement of retinal MRO2 using inverse Fourier transform spectral reconstruction. We called this newly developed technology vis-OCT, and showed that vis-OCT was able to measure the sO2 value in every single major retinal vessel around the optical disk as well as in micro retinal vessels. When breathing normal air, the averaged sO2 in arterial and venous blood in Long-Evans rats was measured to be 95% and 72%, respectively. When we challenge the rats using air mixtures with different oxygen concentrations, vis-OCT measurement followed analytical models of retinal oxygen diffusion and pulse oximeter well.

Age-Related Alterations in the Retinal Microvasculature, Microcirculation, and Microstructure.

PubMed

Wei, Yantao; Jiang, Hong; Shi, Yingying; Qu, Dongyi; Gregori, Giovanni; Zheng, Fang; Rundek, Tatjana; Wang, Jianhua

2017-07-01

To characterize age-related alterations in the retinal microcirculation, microvascular network, and microstructure in healthy subjects. Seventy-four healthy subjects aged from 18 to 82 years were recruited and divided into four age groups (G1 with age <35 years, G2 with age 35 ∼ 49 years, G3 with age 50 ∼ 64 years, and G4 with age ≥65 years). Custom ultra-high resolution optical coherence tomography (UHR-OCT) was used to acquire six intraretinal layers of the macula. OCT angiography (OCTA) was used to image the retinal microvascular network. The retinal blood flow velocity (BFV) was measured using a Retinal Function Imager (RFI). Compared to G1, G2 had significant thinning of the retinal nerve fiber layer (RNFL) (P < 0.05), while G3 had thinning of the RNFL and ganglion cell and inner plexiform layer (GCIPL) (P < 0.05), in addition to thickening of the outer plexiform layer (OPL) and photoreceptor layer (PR) (P < 0.05). G4 had loss in retinal vessel density, thinning in RNFL and GCIPL, and decrease in venular BFV, in addition to thickening of the OPL and PR (P < 0.05). Age was negatively related to retinal vessel densities, the inner retinal layers, and venular BFV (P < 0.05). By contrast, age was positively related to OPL and PR (P < 0.05). During aging, decreases in retinal vessel density, inner retinal layer thickness, and venular BFV were evident and impacted each other as observed by simultaneous changes in multiple retinal components.

Age-Related Alterations in the Retinal Microvasculature, Microcirculation, and Microstructure

PubMed Central

Wei, Yantao; Jiang, Hong; Shi, Yingying; Qu, Dongyi; Gregori, Giovanni; Zheng, Fang; Rundek, Tatjana; Wang, Jianhua

2017-01-01

Purpose To characterize age-related alterations in the retinal microcirculation, microvascular network, and microstructure in healthy subjects. Methods Seventy-four healthy subjects aged from 18 to 82 years were recruited and divided into four age groups (G1 with age <35 years, G2 with age 35 ∼ 49 years, G3 with age 50 ∼ 64 years, and G4 with age ≥65 years). Custom ultra-high resolution optical coherence tomography (UHR-OCT) was used to acquire six intraretinal layers of the macula. OCT angiography (OCTA) was used to image the retinal microvascular network. The retinal blood flow velocity (BFV) was measured using a Retinal Function Imager (RFI). Results Compared to G1, G2 had significant thinning of the retinal nerve fiber layer (RNFL) (P < 0.05), while G3 had thinning of the RNFL and ganglion cell and inner plexiform layer (GCIPL) (P < 0.05), in addition to thickening of the outer plexiform layer (OPL) and photoreceptor layer (PR) (P < 0.05). G4 had loss in retinal vessel density, thinning in RNFL and GCIPL, and decrease in venular BFV, in addition to thickening of the OPL and PR (P < 0.05). Age was negatively related to retinal vessel densities, the inner retinal layers, and venular BFV (P < 0.05). By contrast, age was positively related to OPL and PR (P < 0.05). Conclusions During aging, decreases in retinal vessel density, inner retinal layer thickness, and venular BFV were evident and impacted each other as observed by simultaneous changes in multiple retinal components. PMID:28744554

Retinal and visual system: occupational and environmental toxicology.

PubMed

Fox, Donald A

2015-01-01

Occupational chemical exposure often results in sensory systems alterations that occur without other clinical signs or symptoms. Approximately 3000 chemicals are toxic to the retina and central visual system. Their dysfunction can have immediate, long-term, and delayed effects on mental health, physical health, and performance and lead to increased occupational injuries. The aims of this chapter are fourfold. First, provide references on retinal/visual system structure, function, and assessment techniques. Second, discuss the retinal features that make it especially vulnerable to toxic chemicals. Third, review the clinical and corresponding experimental data regarding retinal/visual system deficits produced by occupational toxicants: organic solvents (carbon disulfide, trichloroethylene, tetrachloroethylene, styrene, toluene, and mixtures) and metals (inorganic lead, methyl mercury, and mercury vapor). Fourth, discuss occupational and environmental toxicants as risk factors for late-onset retinal diseases and degeneration. Overall, the toxicants altered color vision, rod- and/or cone-mediated electroretinograms, visual fields, spatial contrast sensitivity, and/or retinal thickness. The findings elucidate the importance of conducting multimodal noninvasive clinical, electrophysiologic, imaging and vision testing to monitor toxicant-exposed workers for possible retinal/visual system alterations. Finally, since the retina is a window into the brain, an increased awareness and understanding of retinal/visual system dysfunction should provide additional insight into acquired neurodegenerative disorders. © 2015 Elsevier B.V. All rights reserved.

LONGITUDINAL STRUCTURAL CHANGES IN LATE-ONSET RETINAL DEGENERATION.

PubMed

Cukras, Catherine; Flamendorf, Jason; Wong, Wai T; Ayyagari, Radha; Cunningham, Denise; Sieving, Paul A

2016-12-01

To characterize longitudinal structural changes in early stages of late-onset retinal degeneration to investigate pathogenic mechanisms. Two affected siblings, both with a S163R missense mutation in the causative gene C1QTNF5, were followed for 8+ years. Color fundus photos, fundus autofluorescence images, near-infrared reflectance fundus images, and spectral domain optical coherence tomography scans were acquired during follow-up. Both patients, aged 45 and 50 years, had good visual acuities (>20/20) in the context of prolonged dark adaptation. Baseline color fundus photography demonstrated yellow-white, punctate lesions in the temporal macula that correlated with a reticular pattern on fundus autofluorescence and near-infrared reflectance imaging. Baseline spectral domain optical coherence tomography imaging revealed subretinal deposits that resemble reticular pseudodrusen described in age-related macular degeneration. During follow-up, these affected areas developed confluent thickening of the retinal pigment epithelial layer and disruption of the ellipsoid zone of photoreceptors before progressing to overt retinal pigment epithelium and outer retinal atrophy. Structural changes in early stages of late-onset retinal degeneration, revealed by multimodal imaging, resemble those of reticular pseudodrusen observed in age-related macular degeneration and other retinal diseases. Longitudinal follow-up of these lesions helps elucidate their progression to frank atrophy and may lend insight into the pathogenic mechanisms underlying diverse retinal degenerations.

Arrestin gene mutations in autosomal recessive retinitis pigmentosa.

PubMed

Nakazawa, M; Wada, Y; Tamai, M

1998-04-01

To assess the clinical and molecular genetic studies of patients with autosomal recessive retinitis pigmentosa associated with a mutation in the arrestin gene. Results of molecular genetic screening and case reports with DNA analysis and clinical features. University medical center. One hundred twenty anamnestically unrelated patients with autosomal recessive retinitis pigmentosa. DNA analysis was performed by single strand conformation polymorphism followed by nucleotide sequencing to search for a mutation in exon 11 of the arrestin gene. Clinical features were characterized by visual acuity slitlamp biomicroscopy, fundus examinations, fluorescein angiography, kinetic visual field testing, and electroretinography. We identified 3 unrelated patients with retinitis pigmentosa associated with a homozygous 1-base-pair deletion mutation in codon 309 of the arrestin gene designated as 1147delA. All 3 patients showed pigmentary retinal degeneration in the midperipheral area with or without macular involvement. Patient 1 had a sibling with Oguchi disease associated with the same mutation. Patient 2 demonstrated pigmentary retinal degeneration associated with a golden-yellow reflex in the peripheral fundus. Patients 1 and 3 showed features of retinitis pigmentosa without the golden-yellow fundus reflex. Although the arrestin 1147delA has been known as a frequent cause of Oguchi disease, this mutation also may be related to the pathogenesis of autosomal recessive retinitis pigmentosa. This phenomenon may provide evidence of variable expressivity of the mutation in the arrestin gene.

[Cytomegalovirus retinitis in HIV negative patients - retrospective study].

PubMed

Beňová, A; Brichová, M; Svozílková, P; Kousal, B; Jeníčková, D; Heissigerová, J; Ríhová, E

2013-12-01

To evaluate own experience with the diagnosis and treatment of cytomegalovirus (CMV) retinitis in HIV negative patients with immunodeficiency. Retrospective study and case reports. In the Centre for diagnosis and treatment of Uveitis 1869 patients with uveitis we have examined from June 2003 to June 2012. CMV retinitis was diagnosed in 7 patients (1 woman and 6 men) according to the typical clinical findings and history of immunodeficiency. In 2 atypical findings was the diagnosis confirmed by determination of DNA pathogen in vitreous sample (a patient with non-Hodgkin lymphoma) or by positive serology (CMV in leukocytes - indolent form of CMV retinitis in a patient with systemic lupus erythematosus). In 8 cases we found fulminant form, in 1 case indolent form of CMV retinitis. The average age of patients was 39,1 years (18-51 years old), ratio of men to women 6 : 3. In 6 of 9 cases we noticed bilateral retinitis. The average period of observation in our study was 15,8 months (1-48 months). Five of our patients underwent bone marrow transplantation, 2 patients were treated with systemic immunosuppressive drugs (colitis ulcerosa, systemic lupus erythematosus) and 2 patients had chemotherapy for lymphoma. The initiation or modification of treatment (gancyklovir p.o./i.v., foscarnet i.v.) was consulted and coordinated with others specialists. After initiation of treatment we followed-up 7 patients. In 4 eyes of 3 patients (31 %) the improvement of visual acuity was documented, in 5 eyes of 5 patients (38 %) the visual acuity was stabilized. The worsening of vision in 4 eyes of 3 patients (31 %) was caused by complications without any connection to virostatic therapy. All of our patients, who underwent bone marrow transplantation, died within 12 months since the diagnosis of CMV retinitis was determined. The diagnosis of CMV retinitis only in 9 cases (0,48% of all uveitic patients) confirms the rare occurrence of this retinitis. The important tool to the diagnosis of

Neuroprotective therapy for argon-laser-induced retinal injury

NASA Astrophysics Data System (ADS)

Belkin, Michael; Rosner, Mordechai; Solberg, Yoram; Turetz, Yosef

1999-06-01

Laser photocoagulation treatment of the central retina is often complicated by an immediate side effect of visual impairment, caused by the unavoidable laser-induced destruction of the normal tissue lying adjacent to the lesion and not affected directly by the laser beam. Furthermore, accidental laser injuries are at present untreatable. A neuroprotective therapy for salvaging the normal tissue might enhance the benefit obtained from treatment and allow safe perifoveal photocoagulation. We have developed a rat model for studying the efficacy of putative neuroprotective compounds in ameliorating laser-induced retinal damage. Four compounds were evaluated: the corticosteroid methylprednisolone, the glutamate-receptor blocker MK-801, the anti-oxidant enzyme superoxide dismutase, and the calcim-overload antagonist flunarizine. The study was carried out in two steps: in the first, the histopathological development of retinal laser injuries was studied. Argon laser lesions were inflicted in the retinas of 18 pigmented rats. The animals were sacrificed after 3, 20 or 60 days and their retinal lesions were evaluated under the light microscope. The laser injury mainly involved the outer layers of the retina, where it destroyed significant numbers of photoreceptor cells. Over time, evidence of two major histopathological processes was observed: traction of adjacent nomral retinal cells into the central area of the lesion forming an internal retinal bulging, and a retinal pigmented epithelial proliferative reaction associated with subretinal neovascularization and invations of the retinal lesion site by phagocytes. The neuroprotective effects of each of the four compounds were verified in a second step of the study. For each drug tested, 12 rats were irradiated wtih argon laser inflictions: six of them received the tested agent while the other six were treated with the corresponding vehicle. Twenty days after laser expsoure, the rats were sacrificed and their lesions were

Comparison of low-cost handheld retinal camera and traditional table top retinal camera in the detection of retinal features indicating a risk of cardiovascular disease

NASA Astrophysics Data System (ADS)

Joshi, V.; Wigdahl, J.; Nemeth, S.; Zamora, G.; Ebrahim, E.; Soliz, P.

2018-02-01

Retinal abnormalities associated with hypertensive retinopathy are useful in assessing the risk of cardiovascular disease, heart failure, and stroke. Assessing these risks as part of primary care can lead to a decrease in the incidence of cardiovascular disease-related deaths. Primary care is a resource limited setting where low cost retinal cameras may bring needed help without compromising care. We compared a low-cost handheld retinal camera to a traditional table top retinal camera on their optical characteristics and performance to detect hypertensive retinopathy. A retrospective dataset of N=40 subjects (28 with hypertensive retinopathy, 12 controls) was used from a clinical study conducted at a primary care clinic in Texas. Non-mydriatic retinal fundus images were acquired using a Pictor Plus hand held camera (Volk Optical Inc.) and a Canon CR1-Mark II tabletop camera (Canon USA) during the same encounter. The images from each camera were graded by a licensed optometrist according to the universally accepted Keith-Wagener-Barker Hypertensive Retinopathy Classification System, three weeks apart to minimize memory bias. The sensitivity of the hand-held camera to detect any level of hypertensive retinopathy was 86% compared to the Canon. Insufficient photographer's skills produced 70% of the false negative cases. The other 30% were due to the handheld camera's insufficient spatial resolution to resolve the vascular changes such as minor A/V nicking and copper wiring, but these were associated with non-referable disease. Physician evaluation of the performance of the handheld camera indicates it is sufficient to provide high risk patients with adequate follow up and management.

Thrombospondin-2 Expression During Retinal Vascular Development and Neovascularization.

PubMed

Fei, Ping; Palenski, Tammy L; Wang, Shoujian; Gurel, Zafer; Hankenson, Kurt D; Sorenson, Christine M; Sheibani, Nader

2015-09-01

To determine thrombospondin-2 (TSP2) expression and its impact on postnatal retinal vascular development and retinal neovascularization. The TSP2-deficient (TSP2(-/-)) mice and a line of TSP2 reporter mice were used to assess the expression of TSP2 during postnatal retinal vascular development and neovascularization. The postnatal retinal vascularization was evaluated using immunostaining of wholemount retinas prepared at different postnatal days by collagen IV staining and/or TSP2 promoter driven green fluorescent protein (GFP) expression. The organization of astrocytes was evaluated by glial fibrillary acidic protein (GFAP) staining. Retinal vascular densities were determined using trypsin digestion preparation of wholemount retinas at 3- and 6-weeks of age. Retinal neovascularization was assessed during the oxygen-induced ischemic retinopathy (OIR). Choroidal neovascularization (CNV) was assessed using laser-induced CNV. Using the TSP2-GFP reporter mice, we observed significant expression of TSP2 mRNA in retinas of postnatal day 5 (P5) mice, which increased by P7 and remained high up to P42. Similar results were observed in retinal wholemount preparations, and western blotting for GFP with the highest level of GFP was observed at P21. In contrast to high level of mRNA at P42, the GFP fluorescence or protein level was dramatically downregulated. The primary retinal vasculature developed at a faster rate in TSP2(-/-) mice compared with TSP2(+/+) mice up to P5. However, the developing retinal vasculature in TSP2(+/+) mice caught up with that of TSP2(-/-) mice after P7. No significant differences in retinal vascular density were observed at 3- or 6-weeks of age. TSP2(-/-) mice also exhibited a similar sensitivity to the hyperoxia-mediated vessel obliteration and similar level of neovascularization during OIR as TSP2(+/+) mice. Lack of TSP2 expression minimally affected laser-induced CNV compared with TSP2(+/+) mice. Lack of TSP2 expression was associated with

Cytomegalovirus retinitis in patients with AIDS after initiating antiretroviral therapy

PubMed Central

Jabs, Douglas A.; Van Natta, Mark L.; Holland, Gary N.; Danis, Ronald

2016-01-01

Purpose To evaluate the rates of new-onset cytomegalovirus (CMV) retinitis and worsening existing CMV retinitis in patients with AIDS after initiating combination antiretroviral therapy (cART) and the role of an immune recovery inflammatory syndrome (IRIS). Design Cohort study Methods Immune recovery was defined as an increase in CD4+ T cells to ≥100 cells/μL; rates of new-onset CMV retinitis and of worsening of CMV retinitis (either increasing border activity or retinitis progression) were compared between those with and without immune recovery. Results Among patients without CMV retinitis, 1 of 75 patients with immune recovery developed CMV retinitis in the first 6 months after initiating cART vs. 1 of 31 without immune recovery (P=0.14). Among patients with CMV retinitis, the rates of retinitis progression and increasing retinitis border activity among patients during the first 6 months after initiating cART in those with immune recovery were 0.11/PY (95% confidence interval [CI] 0, 0.62) and 0.11/PY (95% CI 0, 0.62), respectively, vs. 0.67/PY (95% CI 0.22, 1.56) and 0.40/PY (95% CI 0.08, 1.17), respectively, for those without immune recovery (P=0.11 and 0.47). Conclusions Among persons with AIDS who experience immune recovery, there was neither an increased rate of new-onset CMV retinitis nor worsening of existing CMV retinitis in the first 6 months after initiating cART vs. those without immune recovery. These data are consistent with the known 3–6 month lag in recovery of specific immunity to CMV after initiating cART and suggest that “immune recovery retinitis”, a proposed IRIS phenomenon, is rare. PMID:27984023

Human bone marrow mesenchymal stem cells for retinal vascular injury.

PubMed

Wang, Jin-Da; An, Ying; Zhang, Jing-Shang; Wan, Xiu-Hua; Jonas, Jost B; Xu, Liang; Zhang, Wei

2017-09-01

To examine the potential of intravitreally implanted human bone marrow-derived mesenchymal stem cells (BMSCs) to affect vascular repair and the blood-retina barrier in mice and rats with oxygen-induced retinopathy, diabetic retinopathy or retinal ischaemia-reperfusion damage. Three study groups (oxygen-induced retinopathy group: 18 C57BL/6J mice; diabetic retinopathy group: 15 rats; retinal ischaemia-reperfusion model: 18 rats) received BMSCs injected intravitreally. Control groups (oxygen-induced retinopathy group: 12 C57BL/6J mice; diabetic retinopathy group: 15 rats; retinal ischaemia-reperfusion model: 18 rats) received an intravitreal injection of phosphate-buffered saline. We applied immunohistological techniques to measure retinal vascularization, spectroscopic measurements of intraretinally extravasated fluorescein-conjugated dextran to quantify the blood-retina barrier breakdown, and histomorphometry to assess retinal thickness and retinal ganglion cell count. In the oxygen-induced retinopathy model, the study group with intravitreally injected BMSCs as compared with the control group showed a significantly (p = 0.001) smaller area of retinal neovascularization. In the diabetic retinopathy model, study group and control group did not differ significantly in the amount of intraretinally extravasated dextran. In the retinal ischaemia-reperfusion model, on the 7th day after retina injury, the retina was significantly thicker in the study group than in the control group (p = 0.02), with no significant difference in the retinal ganglion cell count (p = 0.36). Intravitreally implanted human BMSCs were associated with a reduced retinal neovascularization in the oxygen-induced retinopathy model and with a potentially cell preserving effect in the retinal ischaemia-reperfusion model. Intravitreal BMSCs may be of potential interest for the therapy of retinal vascular disorders. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley

Automated retinal fovea type distinction in spectral-domain optical coherence tomography of retinal vein occlusion

NASA Astrophysics Data System (ADS)

Wu, Jing; Waldstein, Sebastian M.; Gerendas, Bianca S.; Langs, Georg; Simader, Christian; Schmidt-Erfurth, Ursula

2015-03-01

Spectral-domain Optical Coherence Tomography (SD-OCT) is a non-invasive modality for acquiring high- resolution, three-dimensional (3D) cross-sectional volumetric images of the retina and the subretinal layers. SD-OCT also allows the detailed imaging of retinal pathology, aiding clinicians in the diagnosis of sight degrading diseases such as age-related macular degeneration (AMD), glaucoma and retinal vein occlusion (RVO). Disease diagnosis, assessment, and treatment will require a patient to undergo multiple OCT scans, possibly using multiple scanners, to accurately and precisely gauge disease activity, progression and treatment success. However, cross-vendor imaging and patient movement may result in poor scan spatial correlation potentially leading to incorrect diagnosis or treatment analysis. The retinal fovea is the location of the highest visual acuity and is present in all patients, thus it is critical to vision and highly suitable for use as a primary landmark for cross-vendor/cross-patient registration for precise comparison of disease states. However, the location of the fovea in diseased eyes is extremely challenging to locate due to varying appearance and the presence of retinal layer destroying pathology. Thus categorising and detecting the fovea type is an important prior stage to automatically computing the fovea position. Presented here is an automated cross-vendor method for fovea distinction in 3D SD-OCT scans of patients suffering from RVO, categorising scans into three distinct types. OCT scans are preprocessed by motion correction and noise filing followed by segmentation using a kernel graph-cut approach. A statistically derived mask is applied to the resulting scan creating an ROI around the probable fovea location from which the uppermost retinal surface is delineated. For a normal appearance retina, minimisation to zero thickness is computed using the top two retinal surfaces. 3D local minima detection and layer thickness analysis are used

Active retinitis in an infant with postnatally acquired cytomegalovirus infection.

PubMed

Piersigilli, F; Catena, G; De Gasperis, M R; Lozzi, S; Auriti, C

2012-07-01

Congenital cytomegalovirus (CMV) is frequently associated with active retinitis. In contrast, in the immunocompetent neonate with postnatally acquired CMV infection retinitis is rarely present and usually does not progress. We describe the case of an infant with postnatal CMV infection and active retinitis diagnosed at 20 days of life. Owing to the rapid progression of the retinitis, therapy with intravenous ganciclovir was performed, with prompt regression of the retinitis. Therapy was then continued with oral valganciclovir for one further week. Although very unusual, CMV retinitis has to be taken into consideration in neonates with early postnatally acquired CMV infection, as an early diagnosis and treatment may be crucial to avoid visual impairment.

Hemorrhagic fever with renal syndrome and Crimean-Congo hemorrhagic fever as causes of acute undifferentiated febrile illness in Bulgaria.

PubMed

Christova, Iva; Younan, Rasha; Taseva, Evgenia; Gladnishka, Teodora; Trifonova, Iva; Ivanova, Vladislava; Spik, Kristin; Schmaljohn, Connie; Mohareb, Emad

2013-03-01

Hemorrhagic fever with renal syndrome (HFRS) and Crimean-Congo hemorrhagic fever (CCHF) are the 2 widespread viral hemorrhagic fevers occurring in Europe. HFRS is distributed throughout Europe, and CCHF has been reported mainly on the Balkan Peninsula and Russia. Both hemorrhagic fevers are endemic in Bulgaria. We investigated to what extent acute undifferentiated febrile illness in Bulgaria could be due to hantaviruses or to CCHF virus. Using enzyme-linked immunosorbent assays (ELISAs), we tested serum samples from 527 patients with acute febrile illness for antibodies against hantaviruses and CCHF virus. Immunoglobulin M (IgM) antibodies against hantaviruses were detected in 15 (2.8%) of the patients. Of the 15 hantavirus-positive patients, 8 (1.5%) were positive for Dobrava virus (DOBV), 5 (0.9%) were positive for Puumala virus (PUUV), and the remaining 2 were positive for both hantaviruses. A plaque reduction neutralization test (PRNT) confirmed 4 of the 10 DOBV-positive samples. PRNT was negative for all PUUV-positive samples. Serologic evidence of recent CCHF virus infection was found in 13 (2.5%) of the patients. Interestingly, HFRS and CCHF were not only detected in well-known endemic areas of Bulgaria but also in nonendemic regions. Our results suggested that in endemic countries, CCHF and/or HFRS might appear as a nonspecific febrile illness in a certain proportion of patients. Physicians must be aware of possible viral hemorrhagic fever cases, even if hemorrhages or renal impairment are not manifested.

[Paediatric retinal detachment and hereditary vitreoretinal disorders].

PubMed

Meier, P

2013-09-01

The number of retinal detachments in children is very low in comparison to the number in adults. One predisposing factor for development of paediatric retinal detachment is suffering from hereditary vitreoretinal degeneration (e.g., Stickler syndrome, Wagner syndrome, Kniest dysplasia, familial exudative vitreoretinopathy, congenital X-linked retinoschisis, Knobloch syndrome, incontinentia pigmenti, Norrie disease). Hereditary vitreoretinopathies are characterised by an abnormal-appearing vitreous gel with associated retinal changes. In most of these eyes further ocular abnormalities can be diagnosed. A group of hereditary disorders is associated with characteristic systemic abnormalities. Allied conditions should be considered in the clinical diagnosis. Vitreoretinopathies are the most common cause of inherited retinal detachment. In most eyes primary vitrectomy is necessary, and disease-specific surgical treatment is discussed. Georg Thieme Verlag KG Stuttgart · New York.

Neonatal venous cerebral hemorrhage. Report of two cases.

PubMed

Misra, Sanjay N; Misra, Ashish K

2003-10-15

Intracranial pathological changes can occur as a result of impaired craniocervical venous return. Thrombosis of central venous access catheters was demonstrated in two neonates born at 38 and 27 weeks' gestation. Neither infant developed hemorrhage of prematurity as confirmed on cranial ultrasonography. Clinical evidence of vena cava thrombosis and associated spontaneous intraventricular hemorrhage developed on Day 24 and 36, respectively, and these findings were confirmed on imaging studies. In one infant the hemorrhage was accompanied by communicating hydrocephalus. The cause of the intracranial disease was attributable to the retrograde cerebral venous congestion. This, together with the primitive venous bed developing in the periventricular region, was associated with the spontaneous hemorrhage in the region of the foramen of Monro. To the authors' knowledge, this is the first report in the English-language literature of spontaneous neonatal intracerebral hemorrhage, due to thrombosis of the superior or inferior vena cava. The natural history of this condition is resolution without sequelae after appropriate therapeutic intervention for the vena cava thrombosis.

Unilateral retinitis pigmentosa sine pigmento.

PubMed

Pearlman, J T; Saxton, J; Hoffman, G

1976-05-01

A patient presented with unilateral findings of night blindness shown by impaired rod function and dark adaptation, constricted visual fields with good central acuity, a barely recordable electro-retinographic b-wave, and a unilaterally impaired electro-oculogram. There were none of the pigmentary changes usually associated with retinitis pigmentosa. The unaffected right eye was normal in all respects. Therefore the case is most probably one of unilateral retinitis pigmentosa sine pigmento.

Hemorrhagic Transformation of Scrub Typhus Encephalitis: A Rare Entity.

PubMed

Kim, H-C; Yoon, K-W; Yoo, D-S; Cho, C-S

2015-12-01

Central nervous system (CNS) involvement of scrub typhus infection is well known. Most CNS involvement of scrub typhus infection present as meningitis or encephalitis. We report on a patient suffering from hemorrhagic transformation of intracranial lesions caused by Orientia tsutsugamushi. A 53-year-old female farmer who was infected by scrub typhus was treated with doxycycline and recovered from the systemic illness. However, headache persisted. Brain radiologic studies revealed acute intracranial hemorrhage and enhancing lesion, which implied a CNS involvement. Hemorrhagic transformation of encephalitis by scrub typhus is very rare complication and to our best knowledge, this is the first report of hemorrhagic transformation of scrub typhus encephalitis. Clinician should consider the possibility of hemorrhagic transformation of encephalitis in cases of scrub typhus infection.

Pathogenesis of Ebola Hemorrhagic Fever in Cynomolgus Macaques

DTIC Science & Technology

2003-12-01

Pathogenesis of Ebola Hemorrhagic Fever in Cynomolgus Macaques Evidence that Dendritic Cells Are Early and Sustained Targets of Infection Thomas W...is known about the development of EBOV hemorrhagic fever . In the present study, 21 cynomol- gus monkeys were experimentally infected with EBOV and...Am J Pathol 2003, 163:2347–2370) Among viruses causing hemorrhagic fever (HF), and among emerging infectious diseases with global impact in general

Lethal Ultra-Early Subarachnoid Hemorrhage Due to Rupture of De Novo Aneurysm 5 Months After Primary Aneurysmatic Subarachnoid Hemorrhage.

PubMed

Walter, Johannes; Unterberg, Andreas W; Zweckberger, Klaus

2018-05-01

Approximately 1% of all patients surviving rupture of a cerebral aneurysm suffer from a second aneurysmatic subarachnoid hemorrhage later in their lives, 61% of which are caused by rupture of a de novo aneurysm. Latency between bleedings is usually many years, and younger patients tend to achieve better outcomes from a second subarachnoid hemorrhage. We report an unusual case of lethal ultra-early rupture of a de novo aneurysm of the anterior communicating artery only 5 months after the initial subarachnoid hemorrhage and complete coiling in a young, healthy male patient. Despite complete aneurysm obliteration, young age, and good recovery, patients may be subjected to secondary subarachnoid hemorrhages from de novo aneurysms after only a few months of the initial bleeding. Early-control magnetic resonance angiography might hence be advisable. Copyright © 2018 Elsevier Inc. All rights reserved.

ROLE OF TYROSINE-SULFATED PROTEINS IN RETINAL STRUCTURE AND FUNCTION

PubMed Central

Kanan, Y.; Al-Ubaidi, M.R.

2014-01-01

The extracellular matrix (ECM) plays a significant role in cellular and retinal health. The study of retinal tyrosine-sulfated proteins is an important first step toward understanding the role of ECM in retinal health and diseases. These secreted proteins are members of the retinal ECM. Tyrosine sulfation was shown to be necessary for the development of proper retinal structure and function. The importance of tyrosine sulfation is further demonstrated by the evolutionary presence of tyrosylprotein sulfotransferases, enzymes that catalyze proteins’ tyrosine sulfation, and the compensatory abilities of these enzymes. Research has identified four tyrosine-sulfated retinal proteins: fibulin 2, vitronectin, complement factor H (CFH), and opticin. Vitronectin and CFH regulate the activation of the complement system and are involved in the etiology of some cases of age-related macular degeneration. Analysis of the role of tyrosine sulfation in fibulin function showed that sulfation influences the protein's ability to regulate growth and migration. Although opticin was recently shown to exhibit anti-angiogenic properties, it is not yet determined what role sulfation plays in that function. Future studies focusing on identifying all of the tyrosine-sulfated retinal proteins would be instrumental in determining the impact of sulfation on retinal protein function in retinal homeostasis and diseases. PMID:25819460

Remote cerebellar hemorrhage following supratentorial craniotomy.

PubMed

Huang, Chih-Yuan; Lee, Po-Hsuan; Lin, Sheng-Hsiang; Chuang, Ming-Tsung; Sun, Yuan-Ting; Hung, Yu-Chang; Lee, E-Jian

2012-06-01

Cerebellar hemorrhage remote from the site of surgery may complicate neurosurgical procedure. The exact pathophysiology of this type of hemorrhage is poorly understood. We retrospectively compared 16 patients who had remote cerebellar hemorrhage (RCH) with a case-matched control cohort, to determine the significance of perisurgical and surgical factors that may predispose patients to such bleeding events. From 1 June 2005 to 31 December 2008, postoperative routine head computed tomographic (CT) scan was performed in our institution and 16 patients with RCH after supratentorial neurosurgical procedure were identified. The medical charts of these 16 cases and a control cohort of 64 patients were recorded. All parameters were analyzed with regards to various variables. The incidence RCH after supratentorial craniotomy increased after postoperative computed tomographic scan. The mechanism of cerebellar hemorrhage in this series of patients is most likely multifactorial. Several variables showed a significant association with the occurrence of RCH. Multivariate analysis indicated that the following two factors independently correlated with occurrence of RCH: (1) postoperative epidural drainage amount; and (2) history of previous cerebrovascular accident (CVA) with cerebral atrophy. All cases with RCH underwent medical treatment and no neurological sequelae associated with RCH. Postoperative epidural drainage amount and history of previous CVA with cerebral atrophy can reliably predict the occurrence of cerebellar hemorrhage after supratentorial craniotomy. One of the most important strategies to minimize hazardous complications is to be aware of these potential risk factors and to take action to prevent them.

Correlation of ultra-widefield fundus autofluorescence patterns with the underlying genotype in retinal dystrophies and retinitis pigmentosa.

PubMed

Trichonas, George; Traboulsi, Elias I; Ehlers, Justis P

2017-01-01

Ultra-widefield fundus autofluorescence (UW-FAF) allows the characterization of the peripheral retinal features of vitreoretinal diseases. The purpose of this study was to examine possible genotypic/phenotypic correlations of UW-FAF patterns in patients with a variety of retinal dystrophies and retinitis pigmentosa (RP). An IRB-approved retrospective consecutive case series study was performed of genetically characterized retinal dystrophy or RP patients who underwent UW-FAF imaging. UW-FAF was performed with the Optos 200Tx system. Clinical variables, genotypic analysis, and phenotypic characteristics were reviewed. Seventeen patients were identified who had identified mutations in retinal dystrophy or RP genes and who also had undergone UW-FAF. Three patients had X-linked RP with RPGR mutations. Six patients had autosomal dominant RP (four with RHO mutations and one with a PRPF31 mutation, and one with RDS/PRPH2 mutation). Four patients had autosomal recessive RP (four with USH2A mutations). Three patients had Leber Congenital Amaurosis (LCA) with mutations including CRB1, CEP290, and RPGRIP1. Macular hyperautofluorescence was noted in all patients. A ring of hyperautofluorescence was clear in patients with RHO and USH2A mutations, and patients with USH2A mutations demonstrated a second ring of hyperautofluorescence. In the periphery, patients with RHO or RPGR mutations exhibited hyperautofluorescence with patchy areas of hypoautofluorescence. Patients with USH2A mutations had a distinctive pattern of diffuse and homogeneous peripheral hypoautofluorescence. UW-FAF may provide important information to facilitate diagnosis and further research is needed to better characterize this technology as an imaging biomarker for genotype association in retinal dystrophies and RP.

Human amniotic fluid promotes retinal pigmented epithelial cells' trans-differentiation into rod photoreceptors and retinal ganglion cells.

PubMed

Ghaderi, Shima; Soheili, Zahra-Soheila; Ahmadieh, Hamid; Davari, Maliheh; Jahromi, Fatemeh Sanie; Samie, Shahram; Rezaie-Kanavi, Mozhgan; Pakravesh, Jalil; Deezagi, Abdolkhalegh

2011-09-01

To evaluate the effect of human amniotic fluid (HAF) on retinal pigmented epithelial cells growth and trans-differentiation into retinal neurons, retinal pigmented epithelium (RPE) cells were isolated from neonatal human cadaver eye globes and cultured in Dulbecco's modified Eagle's medium-F12 supplemented with 10% fetal bovine serum (FBS). Confluent monolayer cultures were trypsinized and passaged using FBS-containing or HAF-containing media. Amniotic fluid samples were received from pregnant women in the first trimester of gestation. Cell proliferation and death enzyme-linked immunosorbent assays were performed to assess the effect of HAF on RPE cell growth. Trans-differentiation into rod photoreceptors and retinal ganglion cells was also studied using immunocytochemistry and real-time polymerase chain reaction techniques. Primary cultures of RPE cells were successfully established under FBS-containing or HAF-containing media leading to rapid cell growth and proliferation. When RPE cells were moved to in vitro culture system, they began to lose their differentiation markers such as pigmentation and RPE65 marker and trans-differentiated neural-like cells followed by spheroid colonies pertaining to stem/progenitor cells were morphologically detected. Immunocytochemistry (ICC) analysis of HAF-treated cultures showed a considerable expression of Rhodopsin gene (30% Rhodopsin-positive cells) indicating trans-differentiation of RPE cells to rod photoreceptors. Real-time polymerase chain reaction revealed an HAF-dose-dependant expression of Thy-1 gene (RGC marker) and significant promoting effect of HAF on RGCs generation. The data presented here suggest that HAF possesses invaluable stimulatory effect on RPE cells growth and trans-differentiation into retinal neurons. It can be regarded as a newly introduced enriched supplement in serum-free kinds of media used in neuro-retinal regeneration studies.

Cytomegalovirus retinitis complicating combination therapy with rituximab and fludarabine.

PubMed

Chan, Thomas S Y; Cheung, Carol Y M; Yeung, Ian Y L; Hwang, Yu-Yan; Gill, Harinder; Wong, Ian Y; Kwong, Yok-Lam

2015-06-01

Cytomegalovirus (CMV) retinitis is exceptionally rare outside the clinical context of acquired immunodeficiency syndrome and organ allografting. In a population where seropositivity for past CMV infection exceeded 90 %, CMV retinitis was observed in five of 138 patients (3.6 %) receiving fludarabine-containing regimens together with rituximab, which was significantly more frequent than in 141 patients receiving fludarabine-containing regimens alone, where no case was observed (P = 0.029). Treatment of CMV retinitis comprised both intravitreal and systemic ganciclovir/foscarnet. Upon recovery, secondary retinal atrophy occurred in all patients, leading to blindness in 86 % of affected eyes. CMV retinitis is an important complication in patients receiving concomitant rituximab and fludarabine-containing regimens.

In vivo fluorescence imaging of primate retinal ganglion cells and retinal pigment epithelial cells

NASA Astrophysics Data System (ADS)

Gray, Daniel C.; Merigan, William; Wolfing, Jessica I.; Gee, Bernard P.; Porter, Jason; Dubra, Alfredo; Twietmeyer, Ted H.; Ahamd, Kamran; Tumbar, Remy; Reinholz, Fred; Williams, David R.

2006-08-01

The ability to resolve single cells noninvasively in the living retina has important applications for the study of normal retina, diseased retina, and the efficacy of therapies for retinal disease. We describe a new instrument for high-resolution, in vivo imaging of the mammalian retina that combines the benefits of confocal detection, adaptive optics, multispectral, and fluorescence imaging. The instrument is capable of imaging single ganglion cells and their axons through retrograde transport in ganglion cells of fluorescent dyes injected into the monkey lateral geniculate nucleus (LGN). In addition, we demonstrate a method involving simultaneous imaging in two spectral bands that allows the integration of very weak signals across many frames despite inter-frame movement of the eye. With this method, we are also able to resolve the smallest retinal capillaries in fluorescein angiography and the mosaic of retinal pigment epithelium (RPE) cells with lipofuscin autofluorescence.

Following the ontogeny of retinal waves: pan-retinal recordings of population dynamics in the neonatal mouse

PubMed Central

Maccione, Alessandro; Hennig, Matthias H; Gandolfo, Mauro; Muthmann, Oliver; van Coppenhagen, James; Eglen, Stephen J; Berdondini, Luca; Sernagor, Evelyne

2014-01-01

The immature retina generates spontaneous waves of spiking activity that sweep across the ganglion cell layer during a limited period of development before the onset of visual experience. The spatiotemporal patterns encoded in the waves are believed to be instructive for the wiring of functional connections throughout the visual system. However, the ontogeny of retinal waves is still poorly documented as a result of the relatively low resolution of conventional recording techniques. Here, we characterize the spatiotemporal features of mouse retinal waves from birth until eye opening in unprecedented detail using a large-scale, dense, 4096-channel multielectrode array that allowed us to record from the entire neonatal retina at near cellular resolution. We found that early cholinergic waves propagate with random trajectories over large areas with low ganglion cell recruitment. They become slower, smaller and denser when GABAA signalling matures, as occurs beyond postnatal day (P) 7. Glutamatergic influences dominate from P10, coinciding with profound changes in activity dynamics. At this time, waves cease to be random and begin to show repetitive trajectories confined to a few localized hotspots. These hotspots gradually tile the retina with time, and disappear after eye opening. Our observations demonstrate that retinal waves undergo major spatiotemporal changes during ontogeny. Our results support the hypotheses that cholinergic waves guide the refinement of retinal targets and that glutamatergic waves may also support the wiring of retinal receptive fields. PMID:24366261

Human organotypic retinal flat-mount culture (HORFC) as a model for retinitis pigmentosa11.

PubMed

Azizzadeh Pormehr, Leila; Daftarian, Narsis; Ahmadian, Shahin; Rezaei Kanavi, Mozhgan; Ahmadieh, Hamid; Shafiezadeh, Mahshid

2018-05-10

The splicing factor PRPF31 is the most commonly mutated general splicing factor in the retinitis pigmentosa. We used a rapid, convenient and cost effective transfection method with an efficient PRPF31 knockdown in HORFC in order to study the effect of PRPF31 downregulation on retinal gene expressions in an ex vivo model. Modified calcium phosphate method was used to transfect HORFC by PRPF31 siRNA. Different times and doses of siRNA for transfection were assayed and optimum condition was obtained. PRPF31 mRNA and protein downregulation were assessed by qRTPCR and Western blot. The tissue viability of HORFC was measured using the MTT. ImageJ analysis on stained retinal sections by immunohistochemistry was used for thickness measurement of outer nuclear photoreceptor layer. The PRPF31 gene downregulation effects on retinal specific gene expression were analyzed by qRTPCR. A total of 50 nM of PRPF31 siRNA transfection after 63 h in HORFC, showed the optimum reduction in the level of PRPF31 mRNA and protein as shown by qRTPCR and Western blot (over 90% and 50% respectively). The PRPF31 mRNA silencing with calcium phosphate had no effect on cell viability in the period of the experiment. Thickness measurement of outer nuclear photoreceptor layer with IHC showed the significant reduction after 63 h of study (P value = 0.02). siRNA induced PRPF31 knockdown, led to reduction of retinal specific mRNA gene expression involved in phototransduction (RHO, GNAT1, RP1), photoreceptor structure (ROM1, FSCN2, CA4, SEMA4) and transcription factor (CRX) (fold change >5), after 63 h. © 2018 Wiley Periodicals, Inc.

Predictors of intracerebral hemorrhage severity and its outcome in Japanese stroke patients.

PubMed

Hosomi, Naohisa; Naya, Takayuki; Ohkita, Hiroyuki; Mukai, Mao; Nakamura, Takehiro; Ueno, Masaki; Dobashi, Hiroaki; Murao, Koji; Masugata, Hisashi; Miki, Takanori; Kohno, Masakazu; Kobayashi, Shotai; Koziol, James A

2009-01-01

The aim of this investigation was to determine the factors influencing acute intracerebral hemorrhage severity on admission and clinical outcomes at discharge. Sixty acute stroke hospitals throughout Japan participated in the Japan Standard Stroke Registry Study (JSSRS), documenting the in-hospital course of 16,630 consecutive patients with acute stroke from January 2001 to March 2004. We identified 2,840 adult patients from the JSSRS who had intracerebral hemorrhage. Intracerebral hemorrhage severity on admission was strongly related to age, previous stroke history, and hemorrhage size in a monotone fashion [chi(2)(9) = 374.5, p < 0.0001]. Drinking history was also predictive of intracerebral hemorrhage severity on admission, but the association was not monotone. Interestingly, intracerebral hemorrhage severity on admission was increased in nondrinking and heavy drinking compared to mild drinking (p < 0.05). Unsuccessful outcome (modified Rankin scale score = 3-6) was related to age, previous stroke history, hemorrhage size, and intracerebral hemorrhage severity on admission [chi(2)(9) = 830.4, p < 0.0001]. Mortality was related to hemorrhage size, intraventricular hemorrhage, intracerebral hemorrhage severity on admission, and surgical operation [chi(2)(7) = 540.4, p < 0.0001]. We could find four varied factors associated with intracerebral hemorrhage severity and its outcomes. Interestingly, intracerebral hemorrhage severity tended to be greater in nondrinking and heavy drinking than mild drinking. Additionally, surgical operation decreased intracerebral hemorrhage mortality. Copyright 2008 S. Karger AG, Basel.

Retinal detachment repair

MedlinePlus

Scleral buckling; Vitrectomy; Pneumatic retinopexy; Laser retinopexy; Rhegmatogenous retinal detachment repair ... eye doctor can close the holes using a laser. This procedure is most often done in the ...

[Spinocerebellar ataxia type 2 associated to pigmentary retinitis].

PubMed

Jiménez-Caballero, Pedro Enrique; Serviá, Mónica

2010-07-01

Ocular disorders are useful in the characterisation of the different types of spinocerebellar ataxias (SCA); pigmentary retinitis is an alteration that is specifically associated to SCA type 7 and is characterised by night blindness, sensitivity to glare and progressive narrowing of the visual field. A 34-year-old woman with clinical symptoms of progressive ataxia and visual impairment secondary to pigmentary retinitis. The patient had a personal history with an autosomal dominant pattern of a similar disorder in her father and paternal grandmother. In the genetic study she presented a triplet expansion in the SCA type 2 gene. CONCLUSIONS; Although pigmentary retinitis belongs to the SCA type 7 phenotype, our patient presented this retinal disorder, as in other cases of SCA type 2. A genetic study for SCA type 2 must therefore be conducted in patients with a degenerative ataxic clinical picture and who present evidence of pigmentary retinitis.

Pathogenesis of rhegmatogenous retinal detachment: predisposing anatomy and cell biology.

PubMed

Mitry, Danny; Fleck, Brian W; Wright, Alan F; Campbell, Harry; Charteris, David G

2010-01-01

The pathogenesis of rhegmatogenous retinal detachment is complex, and our knowledge of the exact mechanism of vitreoretinal attachment and detachment remains incomplete. We performed a Medline, Ovid, and EMBASE search using search words rhegmatogenous, retinal detachment, vitreous, and retinal adhesion. All appropriate articles were reviewed, and the evidence was compiled. Cortical vitreous contains fibrillar collagens type II, V/XI, and IX. The inner limiting membrane of the retina contains collagens type I, IV, VI, and XVIII as well as numerous other glycoproteins and potential adhesion molecules. The distribution and age-related changes in the structure of these molecules play an important role in the formation of a retinal break, which may compromise and disrupt the normal mechanisms of neurosensory retinal adhesion. Rhegmatogenous retinal detachment development is intimately related to changes in the fibrillar structure of the aging vitreous culminating in posterior vitreous detachment with regions of persistent and tangential vitreoretinal traction predisposing to retinal tear formation. A complex interplay of factors such as weakening of vitreoretinal adhesion, posterior migration of the vitreous base, and molecular changes at the vitreoretinal interface are important in predisposing to focal areas of vitreoretinal traction precipitating rhegmatogenous retinal detachment. Once formed, the passage of liquefied vitreous through a retinal break may overwhelm normal neurosensory-retinal pigment epithelium adhesion perpetuating and extending detachment and causing visual loss. To understand the molecular events underlying rhegmatogenous retinal detachment so that new therapies can be developed, it is important to appreciate the structural organization of the vitreous, the biology underlying vitreous liquefaction and posterior vitreous detachment, and the mechanisms of vitreoretinal attachment and detachment.