The diagnostic contribution of indocyanine green to fluorescein angiography in fellow drusen eyes of patients with wet age-related macular degeneration.

PURPOSE: To assess the contribution of indocyanine green angiography (ICGA) to fluorescein angiography (FA) in evaluating fellow drusen eyes of patients with wet age-related macular degeneration (AMD) in the other eye. METHODS: The records of paired FA and ICGA of patients with dry AMD in one eye and wet AMD in the other eye were retrospectively reviewed. Based on color fundus photographs, drusen were graded to low, moderate, or high grade of severity on FA. The FA and ICGA findings were compared. RESULTS: Fifty-two pairs of eyes were included. Fluorescein angiography showed drusen of low severity in 11 (21.2%) eyes, of moderate severity in 31 (59.6%), and of high severity in 10 (19.2%). Leakage on both FA and ICGA was not demonstrated in any case of drusen of low or moderate severity. Only in 2 out of 10 eyes from the high severity group, 3.8% of the eyes of the whole study population, did ICGA reveal occult choroidal neovascularization (CNV) that was not observed on FA. CONCLUSIONS: In selected eyes with drusen of high grade severity, ICGA may detect occult CNV, unrecognized clinically or by FA. ICGA had a small contribution to the diagnosis of occult CNV in fellow drusen eyes with any degree of severity.

The course of age-related macular degeneration following bilateral cataract surgery.

BACKGROUND AND OBJECTIVE: Progression of age-related macular degeneration (AMD) following cataract surgery has been described. The aim of this study was to investigate whether an uneventful postoperative maculopathic course in one eye (the first eye) may predict a similar prognosis for the fellow eye (the second eye). PATIENTS AND METHODS: Thirty-three patients with bilateral, similar, early AMD (defined by the presence of drusen and/or pigmentary abnormalities on fundal examinations and by the absence of late leakage as documented by fluorescein angiography) who had undergone unilateral cataract surgery, had had a stable postoperative maculopathic course following the first operation, and were scheduled for cataract surgery in the second eye were prospectively observed for at least 1 year after the second operation. The course of maculopathy of the second eye was compared with that of the first eye during the follow-up period of the second eye. RESULTS: A total of 9 of the second eyes (27.2%) showed progression to wet AMD. Of these, 1 patient (3%) had progression in both eyes and 8 patients (24.2%) had progression in the second eye only. The conditions of 2 of the first operated on eyes (6.1%) deteriorated (P < .05). Hypertension (P < .05), soft drusen (P < .01), and Nd:YAG laser capsulotomy (P < .05) were risk factors for development of wet AMD. CONCLUSION: In this study, 24.2% of the patients with early AMD who underwent bilateral cataract surgery and had an uneventful maculopathic course in the first eye had wet AMD in the second eye. Thus, patients with early AMD and soft drusen undergoing bilateral cataract surgery should be monitored for early detection of progression of maculopathy. Further prospective studies are needed to determine the course of maculopathy following cataract surgery.

Development of exudative age-related macular degeneration after cataract surgery.

The macular status of patients with findings consistent with early dry age-related macular degeneration (AMD) who underwent an extracapsular cataract extraction with intraocular lens implantation was evaluated by fundoscopy and fluorescein angiography pre-operatively and during the first post-operative year. Five patients who developed the exudative form of AMD, and who represent the problems arising when treating patients with AMD and cataract, are described. Patients who received laser photocoagulation responded with recurrent choroidal neovascularisation. We suggest that patients with signs of age-related changes scheduled for cataract surgery should undergo a thorough pre- and post-operative assessment of their retinal status.

Age-related macular degeneration after extracapsular cataract extraction with intraocular lens implantation.

PURPOSE: To evaluate the course of age-related maculopathy after cataract surgery. METHODS: Included were 47 patients with bilateral, symmetric, early age-related macular degeneration (AMD), documented by fluorescein angiography, who underwent extracapsular cataract extraction with intraocular lens implantation in one eye. The fellow eye served as the control. The patients were retrospectively reviewed or prospectively followed. RESULTS: Wet AMD developed in nine eyes (19.1%) that were treated with surgery compared with two fellow eyes (4.3%). It was detected within 3 months of surgery in four (44.4%) of the nine affected eyes and within 6 to 12 months of surgery in four other eyes (44.4%). Progression to wet AMD occurred significantly more often in men than in women (P < 0.05). Soft drusen were found as a significant ocular risk factor (P < 0.05). The final visual outcome was poor in all eyes with such progression. CONCLUSIONS: In this study, progression of AMD occurred more often in the surgical eyes compared with the fellow eyes. However, the reasons for the progression of AMD after cataract surgery are still uncertain. Further prospective studies are needed to investigate this observation.

Interphotoreceptor retinoid-binding protein (IRBP): expression in the adult and developing Xenopus retina.

Apposition of the neural retina and pigment epithelium is critical to photoreceptor development and function. Interphotoreceptor retinoid-binding protein (IRBP) is a major component of the extracellular matrix separating these epithelia in the African clawed frog Xenopus laevis (Gonzalez-Fernandez et al., [1993], J. Cell Sci. 105:7-21). In the adult retina, IRBP appears to mediate the transport of hydrophobic molecules, particularly retinoids and fatty acids, within the hydrophilic extracellular domain. In this paper, we compare the distribution of IRBP and its mRNA in adult and embryonic Xenopus retina. Xenopus IRBP antisense RNA, labeled with tritium or digoxigenin, was used for in situ hybridizaton studies. For immunohistochemistry, we used an antiserum against Xenopus IRBP expressed in Escherichia coli. In the adult, we found that IRBP is synthesized at similar levels by both rods and cones. The protein is restricted to the interphotoreceptor matrix, with lesser amounts in the pigment epithelial cytoplasm. In the embryo, expression of the mRNA for IRBP is restricted to the central retina, where photoreceptor differentiation has taken place. By contrast, the protein is distributed throughout the embryonic subretinal space. Therefore, the presence of IRBP precedes photoreceptor differentiation. In summary, IRBP is synthesized by both rods and cones and may be internalized by the pigment epithelium. In the embryo, IRBP is synthesized by the central retina and diffuses through the matrix, reaching the undifferentiated peripheral retina. In view of its ligand-binding properties, diffusion of IRBP may provide the peripheral neural retina with a vehicle to transport retinoids and docosahexaenoic acid (molecules critical to normal retinal development) from the pigment epithelium.

Goldfish cones secrete a two-repeat interphotoreceptor retinoid-binding protein.

Vitamin A and fatty acids are critical to photoreceptor structure, function, and development. The transport of these nutrients between the pigment epithelium and neural retina is mediated by interphotoreceptor retinoid-binding protein (IRBP). IRBP, a 133-kDa (human) glycolipoprotein, is the major protein component of the extracellular matrix separating these two cell layers. In amphibians and mammals, IRBP consists of four homologous repeats of about 300 amino acids which form two retinol and four fatty acid-binding sites. Here we show that IRBP in teleosts is a simpler protein composed of only two repeats. Western blot analysis shows that goldfish IRBP is half the size (70 kDa) of IRBP in higher vertebrates. Metabolic labeling studies employing Brefeldin A taken together with in situ hybridization studies and the presence of a signal peptide show that goldfish IRBP is secreted by the cone photoreceptors. The translated amino acid sequence has a calculated molecular weight of 66.7 kDa. The primary structure consists of only two homologous repeats with a similarity score of 52.5%. The last repeats of human and goldfish IRBPs are 69.1% similar with hydrophobic regions being the most similar. These data suggest that two repeats were lost during the evolution of the ray-finned fish (Actinopterygii), or that the IRBP gene duplicated between the emergence of bony fish (Osteichthyes) and amphibians. Acquisition of a multirepeat structure may reflect evolutionary pressure to efficiently transport higher levels of hydrophobic molecules within a finite space. Quadruplication of an ancestral IRBP gene may have been an important event in the evolution of photo-receptors in higher vertebrates.

Cystoid macular oedema following cataract extraction in patients with diabetes.

The course of cystoid macular oedema (CMO) following extracapsular cataract extraction with posterior chamber intraocular lens implantation was prospectively studied in 44 eyes of 44 consecutive diabetic patients without preoperative CMO. In 50% of eyes CMO was observed 6 weeks after surgery and in 25% was still present at 1 year. The preoperative presence of diabetic retinopathy significantly affected the postoperative onset and persistence of CMO. CMO occurred postoperatively in only 32% of eyes without pre-existing diabetic retinopathy and in 81% of eyes with pre-existing diabetic retinopathy (p < 0.05). CMO persisted at 1 year after surgery in only 7% of eyes without pre-existing diabetic retinopathy and in 56% of eyes in which diabetic retinopathy persisted (p < 0.01). Angiographic CMO (that is, detectable only on fluorescein angiography) was more common than clinical CMO (detectable on ophthalmoscopic examination as well) in eyes with no pre-existing diabetic retinopathy, whereas clinical CMO was seen more often than angiographic CMO when diabetic retinopathy was present preoperatively (p < 0.01). The course and final visual outcome of angiographic CMO were more favourable than in clinical CMO. Final visual acuity of at least 6/12 was achieved in 86% of eyes with angiographic CMO and in only 33% of eyes with clinical CMO. On the basis of the above findings we believe that cataract extraction should not be recommended for eyes with pre-existing diabetic retinopathy until the vision has deteriorated to at least 6/30-6/60.

The course of diabetic retinopathy following cataract surgery in eyes previously treated by laser photocoagulation.

The course of diabetic retinopathy following extracapsular cataract extraction with posterior chamber lens implantation in eyes previously treated by laser photocoagulation for diabetic retinopathy was retrospectively studied in 33 eyes (33 patients). In 20 eyes (61%) there was no change in the retinal status postoperatively. In 13 (39%) there was postoperative progression of diabetic retinopathy compared with the fellow non-operated eye, in which progression occurred in nine eyes (27%). The severity of the preoperative status affected the incidence of progression. Four eyes (12%) developed complications of diabetic retinopathy--that is, rubeosis iridis and vitreous haemorrhage--which regressed after lasering. Cystoid macular oedema developed in 13 eyes (39%) and its incidence varied according to the postoperative course of diabetic retinopathy. The majority of the eyes showed a postoperative improvement in vision.

Cystoid macular oedema following neodymium:YAG laser capsulotomy a prospective study.

Neodymium:YAG laser capsulotomy was performed in 65 eyes of 65 patients because of vision loss due to posterior capsular opacification or wrinkling following uneventful extracapsular cataract extraction with intraocular lens implantation. Eyes with pre-existing macular pathology were excluded from this study. In all of the eyes the posterior capsule was successfully opened. None developed clinical or angiographic cystoid macular oedema. One eye developed retinal detachment nine months after capsulotomy.

[Central retinal artery occlusion in a young man].

Central retinal artery occlusion (CRAO) is uncommon in those younger than 50. We present a 42-year-old man who complained of sudden loss of vision in the left eye. Fundus examination showed typical findings of CRAO. Extensive medical work up showed no evidence of diabetes or of cardiovascular, hematologic or collagen disease. However, a malignant tumor of the right testis was found, with metastases in the lung, retroperitoneal lymph nodes and brain. The right testis was resected and chemotherapy and brain irradiation resulted in remission during a follow-up of 2.5 years. The differential diagnosis of CRAO in younger patients is difficult. We believe that metastases from the primary tumor were the cause of CRAO in our patient. The possibility of malignancy with metastatic spread causing CRAO should be considered, particularly in relatively young patients with no other evidence of systemic disease.

Limited choroidal hemorrhage associated with extracapsular cataract extraction.

Limited choroidal hemorrhage was observed in eight (2.2%) of 368 eyes subjected to extracapsular cataract extraction, compared with a rate of 3.07% in our previous study, in which the technique employed was intracapsular extraction. The difference was found to be significant only for eyes with high myopia. Myopia was found to be the main risk factor for the development of limited choroidal hemorrhage, especially when general anesthesia was used. The presence of glaucoma or the combination of extracapsular cataract extraction and trabeculectomy may increase the susceptibility to this complication. The occurrence of limited choroidal hemorrhage did not affect the final visual function.