Angioid streaks in thalassemia intermedia: warning for thromboembolic events.

PURPOSE: Pseudoxanthoma elasticum-like lesions have been described in association with an increased risk for stroke in ß-thalassemia. We describe a patient with thalassemia intermedia and angioid streaks who developed a central retinal artery occlusion and subsequent portal vein thrombosis. METHOD AND PATIENT: Case report of a 47-year-old woman with thalassemia intermedia, angioid streaks, central retinal artery occlusion, and portal vein thrombosis. RESULTS: Our patient presented with a cilioretinal artery-sparing central retinal artery occlusion in the left eye and evidence of angioid streaks in both eyes. One month later, she developed neovascularization of the angle in the left eye and underwent panretinal photocoagulation. Neovascularization of the angle resolved, and final vision was 20/30. She later developed portal vein thrombosis, and anticoagulation was started. CONCLUSION: The finding of angioid streaks in the setting of thalassemia may suggest the presence of a systemically defective elastin layer. This can be a procoagulative factor and may warrant further assessment of the coagulation and cardiovascular system to take prophylactic measures. The occurrence of a thromboembolic event, however, is multifactorial and the end result of interaction of procoagulant and anticoagulant factors.

Ethambutol neuroretinopathy.

OBJECTIVE: To describe the clinical features of ethambutol neuroretinopathy. DESIGN: Case report and meta-analysis of the literature. PARTICIPANTS: A patient with clinical and electrophysiological findings suggestive of ethambutol neuroretinopathy. TESTING: Electroretinogram, electro-oculogram and visual fields. MAIN OUTCOME MEASURE: Clinical and electrophysiological findings. RESULTS: 101 cases were reviewed, retinal findings include retinal pigment epithelial changes, macular edema, flame-shaped hemorrhages. Electroretinogram findings include decreased amplitude and abnormal wave pattern in full field ERG, multifocal or pattern ERG and electro-oculogram findings include abnormal Arden ratio. CONCLUSIONS: Clinical, electrophysiological and in vitro studies support the toxic effect of ethambutol on the retina. Therefore ethambutol ocular toxicity may be a neuroretinopathy.

Glaucoma screening in a high-risk population.

PURPOSE: To evaluate a screening protocol for detection of individuals with a higher risk of chronic open angle glaucoma for which a complete glaucoma evaluation is indicated. PATIENTS AND METHODS: African Americans over 40 years of age in New Haven, CT. In the screening phase, volunteers filled out a questionnaire and underwent measurements of visual acuity, intraocular pressure (IOP) with a Tono-Pen and visual field with Frequency Doubling Technology. Participants were categorized into "glaucoma likely" or "unlikely," but all were encouraged to follow up with a free complete glaucoma exam, which included applanation tonometry, pachymetry, visual fields with a Humphrey Visual Field Analyzer, gonioscopy, and fundoscopy. Based on the latter exam, patients were categorized into "glaucoma likely" (suspects and confirmed glaucoma) or "unlikely" groups. RESULTS: One hundred eighty-four subjects completed both phases of the study and 76 of 93 patients (82%) who were classified as "glaucoma likely" in the final exam, were also classified as "glaucoma likely" in the screening. Adjusted analysis revealed family history of glaucoma in first degree relatives and screening IOP > 21 mm Hg to have statistically significant associations with the final impression of "glaucoma likely." A combination of these findings gave an overall sensitivity of 81.7% with a specificity of 55%. CONCLUSIONS: In the study population, the combination of an IOP > 21 mm Hg and history of glaucoma in a first degree relative allowed the identification of a significant percentage of individuals with a higher risk of chronic open angle glaucoma, for which a complete glaucoma examination is indicated.

Factors associated with failure to follow up after glaucoma screening: a study in an African American population.

PURPOSE: To evaluate variables associated with failure to access free eye care after participating in glaucoma screening. DESIGN: Review of responses to a survey completed by participants during glaucoma screening. PARTICIPANTS: Two hundred seventy-three surveys completed by participants of African descent during screening. METHODS: African Americans 40 years or older participated in community glaucoma screening clinics, which included a survey with demographic and social variables. Each participant was given a preliminary diagnosis and encouraged to attend a free eye clinic for a complete examination. Survey results were correlated with attendance at the follow-up examination, using Student's t test, chi-square test, and logistic regression analysis. MAIN OUTCOME MEASURE: Noncompliance with follow-up after glaucoma screening. RESULTS: When adjusting for risk factors in logistic regression analysis, noncompliance was associated with living alone (P = 0.008), smoking (P = 0.0005), and lacking a car (P<0.01). Odds of noncompliance for participants living alone were 2.2 times higher than those for participants not living alone. Odds of noncompliance for participants who smoked were 3.0 times greater than those for participants who did not smoke. Odds of noncompliance for participants who did not have access to a car for their last eye examination were 2.1 times greater than those for participants who did. CONCLUSION: Socioeconomic factors such as smoking, lack of access to a car for eye examinations, and living alone are associated with noncompliance to follow-up after glaucoma screening clinics. Identifying persons with these variables may facilitate improved compliance.

Light deprivation suppresses the light response of inner retina in both young and adult mouse.

The retinal synaptic network continues its development after birth in mammals. Recent studies show that postnatal development of retinal circuitry depends on visual stimulation. We sought to determine whether there is a time period during which the retina shows evidence of increased plasticity. We examined the effects of light deprivation on the retinal light response of mouse retina using electroretinogram (ERG) measurements. Our results showed that dark rearing mice from birth to postnatal day (P) 30, 60, and 90 suppressed the amplitudes of oscillatory potentials (OPs) and the magnitudes of suppression were age independent. In addition, dark-rearing-produced suppression of OP amplitudes can be completely reversed in both young and adult mice by returning them to cyclic light/dark conditions for 1 to 2 weeks. However, the recovery time course was age dependent with younger animals needing a longer time to achieve a full recovery. Furthermore, dark rearing of P60 mice raised under cyclic light/dark conditions for 30 days resulted in a similar magnitude of suppression of OP amplitudes as in age-matched mice dark reared from birth. These findings demonstrate that both the normal developmental changes and the maintenance of mature inner retinal light response in adult animals require visual stimulation. These results indicate a degree of activity-dependent plasticity in mouse retina that has not been previously described.