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PubMed2001

Phacoemulsification cataract extraction and posterior chamber lens implantation in patients with uveitis.

PURPOSE: This study reports outcomes of phacoemulsification cataract extraction and posterior chamber intraocular lens implantation within the capsular bag in patients with uveitis. METHODS: We retrospectively reviewed the charts of 32 patients (39 eyes) with uveitis who underwent phacoemulsification cataract extraction and posterior chamber intraocular lens implantation by two surgeons at The Cleveland Clinic Foundation from January 1990 to June 1998. Patients with less than 3 months of follow-up were excluded. RESULTS: Diagnoses of uveitis included idiopathic (15 eyes), sarcoidosis (10 eyes), pars planitis (four eyes), CMV retinitis (two eyes), Fuchs heterochromic iridocyclitis (two eyes), syphilis (two eyes), and one eye each of tuberculosis, Crohn's disease, HLA-B27 associated, and acute retinal necrosis. Average follow-up was 20 months (range, 3 to 63 months). Best-corrected visual acuity improved in 37 eyes (95%). Average improvement was 4 +/- 3 Snellen acuity lines (range, 1 to 10 lines). Thirty-four eyes (87%) attained final visual acuity better than or equal to 20/40. Visual loss occurred in one eye (3%) with CMV retinitis. No improvement in visual acuity was seen in one eye (3%) that developed a retinal pigment epithelial detachment. Posterior capsule opacification occurred in 24 eyes (62%), 12 of which required Nd:YAG capsulotomy (31%). Other postoperative complications included recurrence of uveitis (41%), cystoid macular edema (33%), epiretinal membrane formation (15%), and posterior synechiae (8%). CONCLUSIONS: Phacoemulsification cataract extraction with posterior chamber intraocular lens implantation is safe in patients with uveitis. The incidences of recurrence of uveitis, cystoid macular edema, epiretinal membrane, and posterior synechiae were lower than those reported previously for extracapsular cataract extraction.

Adult↗
PubMed1996

Intravitreal cidofovir for the maintenance treatment of cytomegalovirus retinitis.

PURPOSE: To evaluate the efficacy and safety of multiple intravitreal cidofovir (HPMPC) injections given every 5 to 6 weeks for the maintenance treatment of cytomegalovirus (CMV) retinitis. METHODS: A prospective consecutive case series of 53 eyes in 35 patients with acquired immune deficiency syndrome and CMV retinitis was treated with maintenance intravitreal injections of cidofovir (20 micrograms) at one referral center between April 1994 and September 1995. Twenty-four eyes received intravitreal cidofovir as their initial treatment for CMV retinitis (group A), and 29 eyes previously had received systemic therapy (group B). None of the patients in either group received systemic anti-CMV therapy at any time during the study period. Progression of retinitis was the primary end point. RESULTS: All eyes with active retinitis healed in response to treatment. None of the 24 eyes in group A demonstrated any progression during the study period. Four (14%) of the 29 eyes in group B had one episode each of retinitis progression (mean follow-up, 15 weeks; range, 0-58 weeks). In 1 (1.9%) of the 53 eyes, a retinal detachment developed. A mild iritis was observed after 14% of injections, which were prophylaxed with oral probenecid. Irreversible visually significant hypotony developed in two eyes (3.8%). CONCLUSION: Treatment and subsequent maintenance therapy of CMV retinitis with 20 micrograms intravitreally injected cidofovir, given at 5- to 6-week intervals, is highly effective, with only rare episodes of re-activation and progression.

AIDS-Related Opportunistic Infections↗
PubMedDate not supplied

Biostatistical analysis of pseudophakic and aphakic retinal detachments.

Removal of the crystalline lens increases the risk of rhegmatogenous retinal detachment (RD) by creating changes in the ocular environment that predispose to development of retinal breaks. The evolution of cataract surgery from intracapsular cataract extraction (ICCE) to extracapsular cataract extraction (ECCE) and phacoemulsification has reduced the incidence of RD, while advances in vitreoretinal surgery have resulted in improved outcomes when retinal detachment does occur. The incidence of RD varies between 0.4-3.6% for ICCE and between 0.55-1.65% for ECCE. In eyes having undergone phacoemulsification the incidence is similar to those of ECCE and ranges between 0.75-1.65%. In this article the authors review the incidence and risk factors associated with pseudophakic and aphakic RD. The risk factors discussed include pre-operative risk factors such as age, status of the fellow eye and myopia, and surgical risk factors such as vitreous loss, posterior capsular integrity and Nd : YAG capsulotomy.

Aphakia, Postcataract↗
PubMed2006

Pediatric rhegmatogenous retinal detachment in taiwan.

PURPOSE: To describe the clinical features and surgical outcomes in a series of pediatric patients with rhegmatogenous retinal detachments in Taiwan. METHODS: Retrospective study of pediatric patients (age 1 to 15 years) with rhegmatogenous retinal detachment dated between January 1995 and December 2004. Patients with perforating ocular trauma were excluded. Patients were divided into four groups according to the predisposing factors: Group 1, those with congenital or developmental anomalies; Group 2, those with trauma history; Group 3, those with myopia greater than -3 D but excluding patients in Groups 1 and 2; and Group 4, the others with miscellaneous etiologies. Patients' age, sex, medical history, ocular history, type of detachment, macular status, refractive status, previous visual acuity, number and type of surgeries performed, postoperative retinal status, and current visual acuity were recorded. RESULTS: Thirty-five eyes of 32 patients were included in this study. The median age was 13 years, and 75% of patients were boys. There were 17 eyes (49%) in Group 1, 8 in Group 2 (23%), 8 in Group 3 (23%), and 2 in Group 4 (6%). Bilateral retinal detachment was present in 7 patients (22%). In Group 1, familial exudative vitreoretinopathy was present in 7 eyes; retinopathy of prematurity was noted in 5 eyes; Marfan's syndrome was present in 3 eyes; mental and growth retardation was present in 2 eyes. Macula sparing retinal detachment was found in 3 eyes. Retinal attachment was achieved in 28/35 eyes. Visual recovery was modest. CONCLUSION: Congenital or developmental anomalies, myopia, and trauma were the most common risk factors for pediatric rhegmatogenous retinal detachment in Taiwan. Regular follow-up for children at risk of developing rhegmatogenous retinal detachment is necessary for early detection.

Adolescent↗
PubMed1997

Conditioned medium from activated spleen cells supports the survival of rat retinal cells in vitro.

Cytokines are a heterogeneous group of molecules that have been associated with several functions in the nervous system, such as survival and differentiation of neuronal and glial cells. In the present study, we demonstrated that conditioned medium from spleen cells activated with concanavalin A increased neuritogenesis and survival of retinal cells, as measured by biochemical and morphological criteria. Our data showed that conditioned medium induced a five-fold increase in the amount of protein after 120 h in vitro. This effect was not inhibited by the blockade of voltage-dependent L-type calcium channels with 5.0 microM nifedipine. However, the use of an intracellular calcium chelator (15.0 microM BAPTA-AM) inhibited this effect. Our results support the idea that factors secreted by activated lymphocytes, such as cytokines, can modulate the maintenance and the differentiation of rat retinal cells in vitro, indicating a possible role of these molecules in the development of retinal cells, as well as in its protection against pathological conditions.

Animals↗
PubMed1987

Treatment of cytomegalovirus retinitis with ganciclovir.

Eighteen immunocompromised patients with cytomegalovirus (CMV) retinitis were treated with ganciclovir, an investigational antiviral drug. CMV retinitis in association with acquired immune deficiency syndrome (AIDS) developed in 17 patients; CMV retinitis developed in one patient after cardiac transplantation. Fourteen patients responded to ganciclovir treatment with improvement in CMV retinitis. In 11 patients, the response was classified as complete; in three patients, the response was partial. Continued improvement in the retinitis was often seen while the patient was on maintenance treatment. Maintenance ganciclovir therapy was required; relapse occurred in five of seven patients in whom ganciclovir treatment was interrupted. The major limiting toxic side effect of ganciclovir was neutropenia, which necessitated temporary discontinuation of ganciclovir in five patients but was reversible in all cases. Ganciclovir appears to be an effective therapy for CMV retinitis, but chronic maintenance therapy is required.

Acquired Immunodeficiency Syndrome↗
PubMed2005

Detection of paravascular retinal cysts before using OCT in a highly myopic patient.

PURPOSE: We describe a case of high myopia who developed paravascular retinal rarefaction generated by vitreoretinal adhesion on retinal vessels detected using optical coherence tomography (OCT). METHODS: A 31-year-old man received a regular ophthalmologic examination for high myopia including detailed fundus examination and OCT. RESULTS: Detailed fundus examination revealed retinal rarefaction and fissure-like findings alongside the superior temporal retinal artery and vein in the right eye. OCT images revealed vitreoretinal adhesions on the retinal artery and a paravascular cystoid space in the inner retina. There was no retinal detachment. The axial length had increased by 1.50 mm over 15 years. CONCLUSION: Paravascular retinal rarefaction as well as pseudohole formation caused by vitreoretinal adhesion on retinal vessels was detected in this patient using OCT. OCT might be useful to detect early-stage retinal pathologies caused by paravascular vitreoretinal traction in highly myopic patients.

Adult↗
PubMed2001

Long-term activation of adenosine A(2a) receptors blocks glutamate excitotoxicity in cultures of avian retinal neurons.

Previous work showed the presence of adenosine receptors as well as adenosine uptake and release mechanisms in developing chick retinal neurons in culture. In the present work we show that exogenous glutamate or kainate promotes extensive cell death in these cultures which is blocked when the cultures are previously incubated with adenosine. Addition of glutamate or kainate to purified cultures of retinal neurons and photoreceptors induced massive death of cultured cells which was inhibited in both cases by preincubation with MK801, an NMDA antagonist, or DNQX, an AMPA/kainate antagonist. Cell death was also greatly attenuated by preincubation with adenosine plus EHNA, an adenosine deaminase inhibitor, NBI, an adenosine uptake blocker, the permeable cAMP analogs 8-Br cAMP and Sp cAMP and the A(2a) agonists CGS 21680 and DPMA, but not with the A(1) receptor agonist CHA. Kinetic studies performed determining the intracellular LDH activity showed that maximal death was observed after 8 h and in concentrations of glutamate as low as 50 microM. We also observed a time-dependent protective effect of adenosine beginning after 1 h of preincubation and reaching a maximal effect after 24 h, indicating its association with changes in cellular metabolism induced by long-term exposure of cells to the nucleoside. The results show that adenosine inhibits glutamate toxicity in retinal neurons through a long-term activation of A(2a) receptors and elevation of intracellular cyclic AMP levels.

Adenosine↗
PubMed1996

Inhibition of FGF receptor activity in retinal ganglion cell axons causes errors in target recognition.

Native fibroblast growth factor receptor (FGFR) function was inhibited in developing Xenopus retinal ganglion cells (RGCs) by in vivo transfection of a dominant negative FGFR. Axons expressing the dominant negative protein advanced at 60% of the normal speed, but nevertheless navigated appropriately in the embryonic optic pathway. When they neared the optic tectum, however, many axons made erroneous turns, causing them to bypass rather than enter their target. By contrast, RGC axons expressing nonfunctional FGFR mutants entered the tectum correctly. These findings demonstrate a role for FGFR signaling in the extension and targeting of RGC axons and suggest that receptor tyrosine kinase/growth factor interactions play a critical function in establishing initial connectivity in the vertebrate visual system.

Animals↗
PubMed1993

Retinal detachment following anterior chamber lens implantation for the correction of ultra-high myopia in phakic eyes.

The development of retinal detachment is reported in three eyes, of two patients, following implantation of an anterior chamber intraocular lens (AC-IOL) in phakic eyes for the correction of ultra-high myopia. The presence of an AC-IOL may hamper the identification of retinal breaks and removal of the intraocular lens may prove necessary to improve visualisation. Shallowing of the anterior chamber may also occur during, or following, vitreoretinal surgery with risk of endothelial contact. The risks and relative contraindications of AC-IOL implantation into phakic eyes are discussed.

Adult↗
PubMed1999

Surgical treatment of submacular hemorrhage associated with idiopathic polypoidal choroidal vasculopathy.

PURPOSE: To report the visual outcome of surgical treatment of submacular hemorrhage associated with idiopathic polypoidal choroidal vasculopathy. METHODS: Eight eyes of eight consecutive patients with thick submacular hemorrhages associated with idiopathic polypoidal choroidal vasculopathy were treated with pars plana vitrectomy and tissue plasminogen activator-assisted removal of subretinal blood (December 1995 to September 1997) or intravitreal 100% sulfur hexafluoride gas injection without tissue plasminogen activator (October 1997 to March 1998). RESULTS: Postoperatively, laser treatment was performed for active polypoidal lesions outside the foveal avascular zone in four eyes. A retinal pigment epithelial tear was seen outside the foveal avascular zone in three eyes, and one eye developed a retinal detachment. The best-corrected visual acuity improved (by 3 or more lines) or stabilized in seven of the eight eyes. Four eyes had a final best-corrected visual acuity of 20/40 or better, and three eyes had a final best-corrected visual acuity of 20/50 to 20/200. In one eye, the visual acuity decreased from 20/100 to 20/500 because of the development of a subfoveal neovascular membrane. The membrane was excised, and histologic examination showed fibrovascular tissue between the retina and retinal pigment epithelium (type 2 pattern). CONCLUSIONS: Surgical intervention may be of benefit in eyes with submacular hemorrhage associated with idiopathic polypoidal choroidal vasculopathy.

Aged↗
PubMed2003

The spatial order of horizontal cells is not affected by massive alterations in the organization of other retinal cells.

To test whether retinal mosaics develop through interactions that are restricted primarily to the mosaic cells, we studied the horizontal cell mosaic in mutant mice (rd/rd and rd/bcl2) displaying severe retinal abnormalities. These mutants show that the horizontal cell mosaic develops normally even if these cells lack part of their synaptic input, have anomalous morphologies, eventually decrease in number, and reside in an abnormally packed retinal layer. These data strongly support a developmental design in which the final position of each cell in a retinal mosaic is controlled by interactions between homotypic cells and is independent of other cell types. The present analysis is also an investigation of the effects of photoreceptor degeneration on the horizontal cells in an established animal model of retinitis pigmentosa, the rd/rd mouse. We find that the organization of the horizontal cell mosaic resists photoreceptor degeneration and, furthermore, that bcl2 overexpression prevents the partial loss of horizontal cells secondary to photoreceptor loss. Secondary degeneration hampers attempts to restore retinal function by transplanting photoreceptors or promoting their survival. The anti-apoptotic gene bcl2 appears to be a promising tool to rescue inner retinal neurons, increasing the probability that photoreceptor rescue or substitution may be beneficial to subjects suffering from retinal degenerative diseases.

Age Factors↗
PubMed1999

Scanning laser densitometry and color perimetry demonstrate reduced photopigment density and sensitivity in two patients with retinal degeneration.

PURPOSE: To test the feasibility of scanning laser densitometry with a modified Rodenstock scanning laser ophthalmoscope (SLO) to measure the rod and cone photopigment distribution in patients with retinal diseases. METHODS: Scanning laser densitometry was performed using a modified Rodenstock scanning laser ophthalmoscope. The distribution of the photopigments was calculated from dark adapted and bleached images taken with the 514 nm laser of the SLO. This wavelength is absorbed by rod and cone photopigments. Discrimination is possible due to their different spatial distribution. Additionally, to measure retinal sensitivity profiles, dark adapted two color static perimetry with a Tübinger manual perimeter was performed along the horizontal meridian with 1 degree spacing. RESULTS: A patient with retinitis pigmentosa had slightly reduced photopigment density within the central +/- 5 degrees but no detectable photopigment for eccentricities beyond 5 degrees. A patient with cone dystrophy had nearly normal pigment density beyond +/- 5 degrees, but considerably reduced photopigment density within the central +/- 5 degrees. Within the central +/- 5 degrees, the patient with retinitis pigmentosa had normal sensitivity for the red stimulus and reduced sensitivity for the green stimulus. There was no measurable function beyond 7 degrees. The patient with cone dystrophy had normal sensitivity for the green stimulus outside the foveal center and reduced sensitivity for the red stimulus at the foveal center. The results of color perimetry for this patient with a central scotoma were probably influenced by eccentric fixation. CONCLUSION: Scanning laser densitometry with a modified Rodenstock SLO is a useful method to assess the human photopigment distribution. Densitometry results were confirmed by dark adapted two color static perimetry. Photopigment distribution and retinal sensitivity profiles can be measured with high spatial resolution. This may help to measure exactly the temporal development of retinal diseases and to test the success of different therapeutic treatments. Both methods have limitations at the present state of development. However, some of these limitations can be overcome by further improving the instruments.

Adult↗
PubMed1998

The eye in von Hippel-Lindau disease. Long-term follow-up of screening and treatment: recommendations.

Von Hippel-Lindau disease (VHL) is an autosomal dominant tumour syndrome caused by germline mutations of the VHL tumour suppressor gene located on chromosome 3p25-26. In VHL tumours may occur in 14 different target organs, including the eye. Retinal angiomas are considered the first manifestation of VHL disease in 43% of cases, and the cumulative probability of developing a retinal angioma in one or both eyes rises during each decade of life, reaching 80% for patients over 80 years old. Since 1976 patients with VHL at the University Hospital of Utrecht and their at-risk relatives have been screened periodically by a multidisciplinary team. Long-term follow-up ophthalmological data were analysed with special attention to natural course and results of treatment. In addition, we looked for a genotype-phenotype correlation. Retinal angiomas were found in all families. In one large family with a missense mutation (V170D) of the VHL gene, in which the complete spectrum of visceral- and central nervous system (CNS) features of VHL is present, macular, parapapillary, optic disc and ora serrata angiomas were also found. In general, however, a clear-cut genotype-phenotype correlation could not be found. Only early detection and treatment of peripheral retinal angiomas can be expected to decrease the percentage of patients with decreased visual acuity. Therefore, early detection and treatment of these tumours is of paramount importance. Ophthalmological screening of patients and persons at risk should start as early as possible. In patients with apparently sporadic retinal angiomas it is advisable to perform germline DNA analysis, since the risk of developing VHL is high, especially if the angiomas are bilateral, or unilateral and multifocal, if the patient is young, or if there is a family history suggestive of VHL.

Adult↗
PubMed1988

Retinal revascularization following laser photocoagulation treatment for choroidal neovascular membranes.

Retinal revascularization developed within the treatment scar in 7% of patients who had laser photocoagulation treatment for a choroidal neovascular membrane. This revascularization could be mistaken for recurrent choroidal neovascularization because it initially proliferated into a glomerularlike structure and showed dye leakage on angiography. Unlike choroidal neovascularization, these vessels, however, filled entirely from the retinal circulation and stereoscopic angiograms showed them to be located in the inner retina. In the 20 patients who were followed up, the retinal revascularization first appeared approximately four weeks after treatment and persisted for an average of ten weeks. It was associated with dense laser scarring, retinal capillary obliteration, and internal limiting membrane wrinkling, suggesting that heavy initial laser treatment was a predisposing factor for its development. It is important to differentiate retinal revascularization, which has an excellent prognosis and does not require re-treatment, from recurrent choroidal neovascularization, which usually must be treated promptly to avoid loss in visual acuity.

Adult↗
PubMed2004

Embryonic stem cells are capable of generating a neuronal network in the adult mouse retina.

The integration of embryonic stem (ES) cells as well-differentiated neuronal cells into the retinas of adult mice was investigated. ES cells were transplanted in adult mouse retinas by intravitreal injections. Neuronal differentiation of the ES cells was investigated by morphological and immunohistochemical examinations on post-operative days 5 and 30. ES cell apoptosis was examined by in situ terminal dUTP-biotin nick end labeling of DNA fragments. Differentiated ES cells growing along the retinal surface developed fine neuronal cell processes around cell nuclei and generated neuronal networks into the retinal inner plexiform layer (IPL) 30 days after transplantation. The differentiated ES cells expressed retinal and neuronal markers. Many apoptotic cells were recognized in transplanted ES cells at day 5 but not at day 30 after transplantation. ES cells may be useful for neural tissue regeneration in the adult mammalian retina.

Animals↗
PubMed2006

Failure to maintain eye-specific segregation in nob, a mutant with abnormally patterned retinal activity.

Axon terminals from the two eyes initially overlap in the dorsal-lateral geniculate nucleus (dLGN) but subsequently refine to occupy nonoverlapping territories. Retinal activity is required to establish and maintain this segregation. We show that despite the presence of retinal activity, segregated projections desegregate when the structure of activity is altered. Early in development, spontaneous retinal activity in the no b-wave (nob) mouse is indistinguishable from that of wild-type mice, and eye-specific segregation proceeds normally. But, around eye-opening, spontaneous and visually evoked activity in nob retinas become abnormal, coincident with a failure to preserve precise eye-specific territories. Dark-rearing studies suggest that altered visual experience is not responsible. Transgenic rescue of the mutated protein (nyctalopin) within nob retinal interneurons, without rescuing expression in either retinal projection neurons or their postsynaptic targets in the dLGN, restores spontaneous retinal activity patterns and prevents desegregation. Thus, normally structured spontaneous retinal activity stabilizes newly refined retinogeniculate circuitry.

Animals↗
PubMed1998

Cystoid macular edema associated with cytomegalovirus retinitis in patients with the acquired immunodeficiency syndrome.

PURPOSE: To describe the clinical and fluorescein angiographic appearance of cystoid macular edema associated with cytomegalovirus retinitis in patients with the acquired immunodeficiency syndrome (AIDS). METHODS: We retrospectively examined the clinical and photographic records of four patients with AIDS and cytomegalovirus retinitis who developed cystoid macular edema. RESULTS: Seven eyes of four patients with AIDS and cytomegalovirus retinitis experienced decreased vision associated with cystoid macular edema. Vitreous inflammation was mild in each patient. In all eyes, the retinitis involved zone 1, and in all but one eye, the cytomegalovirus retinitis was inactive. In one eye, the cystoid macular edema was worsened by formation of a dense juxtafoveal epiretinal membrane. CONCLUSIONS: Although infrequently recognized, cystoid macular edema can cause visual loss in patients with AIDS and cytomegalovirus retinitis. Fluorescein angiography should be considered in any patient with cytomegalovirus retinitis and unexplained visual loss.

AIDS-Related Opportunistic Infections↗