Faculty Bibliography

PURPOSE: To review the pathophysiologic principles underlying increased autofluorescence from the outer retina and subretinal space using selected diseases as examples. METHODS: The ocular imaging information and histopathologic features, when known, were integrated for diseases causing increased autofluorescence from the outer retina and subretinal space. Inferences were taken from this information and used to create a classification scheme. RESULTS: These diseases are principally those that cause separation of the outer retina from the retinal pigment epithelium, thereby preventing proper phagocytosis of photoreceptor outer segments. The separation can arise from increased exudation into the subretinal space or inadequate removal of fluid from the subretinal space. Lack of normal outer segment processing initially leads to increased accumulation of outer segments on the outer retina and subretinal space. Over time, this material is visible as an increasingly thick coating on the outer retina, is yellow, and is autofluorescent. Over time, atrophy develops with thinning of the deposited material and decreasing autofluorescence. The accumulated material is ultimately capable of inducing damage to the retinal pigment epithelium. Diseases causing accumulation of the material include central serous chorioretinopathy, vitelliform macular dystrophy, acute exudative polymorphous vitelliform maculopathy, choroidal tumors, and vitreomacular traction syndrome. CONCLUSION: The physical separation of the retinal outer segments from the retinal pigment epithelium hinders proper phagocytosis of the outer segments. Accumulation of the shed but not phagocytized outer segments plays a role in disease manifestations for a number of macular diseases

PURPOSE: To report the autofluorescence features of congenital hypertrophy of the retinal pigment epithelium (CHRPE). METHODS: Four patients with CHRPE were evaluated using autofluorescence in a camera-based system. RESULTS: All CHRPE lesions studied had well demarcated borders and were hypoautofluorescent. Presence of a hypopigmented halo and lacunae did not alter the homogeneous hypofluorescence. CONCLUSION: Hypoautofluorescence confirmed the known absence of lipofuscin in the retinal pigment epithelium cells of CHRPE lesions. Autofluorescence imaging may provide useful information in evaluating pigmented lesions of the fundus.

BACKGROUND: Spontaneous scleral rupture in association with retinochoroidal coloboma is a rare and poorly understood event, with few reports in the literature. METHODS: Interventional case report. RESULTS: A 40-year-old man had a spontaneous decline in visual acuity with hypotony in the right eye. Photographic, fluorescein angiographic, optical coherence tomographic, ultrasonographic, and computed tomographic findings demonstrated that the cause was spontaneous rupture of ectatic sclera adjacent to a retinochoroidal coloboma. Surgical repair with primary suture imbrication and support with a segmental scleral buckle restored the intraocular pressure and baseline visual acuity. CONCLUSIONS: The adjacent but distinct locations of the retinochoroidal coloboma and ectatic sclera in this case suggest that during embryogenesis a full thickness defect was present in the eye wall, but due to differential growth rates, the scleral and retinochoroidal defects ceased to be superimposed. Persistent hypotony implies continued flow of liquefied vitreous or aqueous through the defect. Suture imbrication and scleral buckling can be a successful treatment option.

PURPOSE: To investigate risk factors for central retinal vein occlusion (CRVO). DESIGN: Retrospective case-control study. METHODS: Consecutive patients with CRVO examined from July 1, 2005 through July 31, 2006 were compared with an historical gender- and age-matched control group of patients with ocular problems other than vascular occlusive disease from the same referral practice. Risk factors for CRVO were evaluated. RESULTS: The 144 patients in the CRVO group, 87 males and 57 females, had a mean age of 69.6 years (+/-13.6 years). CRVO was associated with hypertension (P < .001), diabetes mellitus (P = .047), glaucoma (P < .001), atrial fibrillation (P = .036), angiotensin-converting enzyme inhibitor use (P = .022), aspirin use (P < .001), and warfarin use (P = .011) by univariate analyses. Postmenopausal estrogen use was more common among women in the control group (P = .029). Multivariate logistic regression found the independent predictors for CRVO to be: glaucoma (adjusted odds ratio [OR], 4.75; P < .001), aspirin use (adjusted OR, 2.66; P = .001), and warfarin use (adjusted OR, 3.34; P = .005). CONCLUSIONS: We found many of the same risk factors previously identified for CRVO by other studies, but we identified both aspirin and warfarin use to be independent risk factors for CRVO. Although these findings suggest the vasculopathic and prothrombotic risks in some patients may not be addressed adequately by antithrombotic therapy, they also suggest that the pathogenesis of CRVO may be more complicated than just the development of a primary thrombus within the vein

PURPOSE: To evaluate the change in visual acuity and retinal appearance in patients after early initiation of intravitreal bevacizumab treatment for central retinal vein occlusion (CRVO). DESIGN: Retrospective, interventional case series. METHODS: Patients with CRVO of fewer than three months' duration receiving intravitreal bevacizumab as primary treatment were evaluated. Patients received an intravitreal 1.25 mg (0.05 ml) bevacizumab injection. Changes in visual acuity, central macular thickness, venous tortuosity and diameter, and optic disk edema were noted. RESULTS: Six eyes of five consecutive patients with CRVO treated with intravitreal bevacizumab injection were reviewed retrospectively. The patients did not have other ocular conditions that could have compromised visual acuity. The mean baseline visual acuity was 20/428 (logarithm of the minimum angle of resolution [logMAR] units, 1.33). The mean follow-up period was 12 months (range, seven to 15 months), and the number of bevacizumab injections ranged from four to 10. The patients showed a statistically significant decrease in optic nerve head swelling, venous tortuosity, and venous diameter, with the largest proportion of change occurring within one month of the first bevacizumab injection. The mean visual acuity at last follow-up was 20/53 (logMAR units, 0.42; P = .035, as compared with baseline). In no patient did collateral vessels at the optic nerve head develop. CONCLUSIONS: The patients experienced a dramatic improvement in the visual acuity and clinical fundus appearance, without collateral vessel formation. These findings are difficult to explain with current theories of the pathophysiologic features of CRVO. These findings also suggest early initiation of anti-vascular endothelial growth factor (VEGF) treatment should be studied in a larger trial for CRVO

PURPOSE: To determine the results of intravitreal bevacizumab injections for the management of choroidal neovascularization (CNV) in patients with pseudoxanthoma elasticum (PXE)-associated angioid streaks. METHODS: A consecutive series of patients with PXE and CNV were managed with intravitreal bevacizumab injection (1.25 mg per 0.05 cc). The main outcome measures were visual acuity and greatest lesion height as measured by optical coherence tomography (OCT). RESULTS: Nine eyes of nine consecutive patients received intravitreal bevacizumab (1.25 mg/0.05 mL) injections. The mean follow-up time was 6 months, during which eyes received an average of 1.8 injections. The baseline visual acuity was a mean of 20/368 and improved to 20/289 at the last visit (P = 0.056). Visual acuity either improved or stabilized in all 9 eyes (100%). Serial OCT measurements in 8 eyes showed a mean of 353 microm at baseline, which decreased to 201 mum at the last visit (P = 0.012). No complications were noted. CONCLUSIONS: These short-term results support the use of intravitreal bevacizumab for the management of CNV in patients with PXE. Continued experience with intravitreal bevacizumab in this population will help establish its longer-term efficacy and better define the potential need for serial injections to maintain these results