Faculty Bibliography

OBJECTIVE: Recent studies have shown that indocyanine-green videoangiography (ICG-V) is useful to image occult choroidal neovascularization. The authors studied the ICG-V findings in fellow drusen eyes of patients with unilateral exudative age-related macular degeneration (AMD). The authors also studied the occurrence of exudative changes to determine whether ICG-V is useful in predicting future exudative changes in these eyes with only drusen. DESIGN: Cohort study. PARTICIPANTS: The authors studied 432 consecutive patients diagnosed with unilateral exudative AMD in whom the fellow eye had only drusen by clinical fundus examination and fluorescein angiography. All of these eyes had ICG-V performed. Follow-up data were obtained in all eyes with abnormal indocyanine-green (ICG) angiograms and randomly sampled ICG angiograms of normal eyes. MAIN OUTCOME MEASURES: The initial ICG findings were classified as showing normal or abnormal hyperfluorescence. Abnormal hyperfluorescence eyes were subdivided into focal spots (focal areas of hyperfluorescence < 1 disc area in size) and plaques (areas of hyperfluorescence > 1 disc area). The development of exudative changes in eyes with normal and abnormal hyperfluorescence was compared. RESULTS: Of the 432 fellow eyes, 386 (89%) eyes with drusen had a normal ICG-V study, whereas 46 (10 focal spots and 36 plaques) (11%) eyes had an abnormal ICG-V. Exudative changes occurred in 6 (10%) of 58 normal ICG eyes and 9 (24%) of 38 eyes with abnormal ICG findings during a mean follow-up period of 21.7 months. The difference between drusen eyes with normal ICG angiograms and those with plaques on ICG-V regarding future exudative changes (10% vs. 27%, respectively) was statistically significant (P = 0.038). CONCLUSIONS: Abnormal ICG findings were found in 11% of eyes with clinically and fluorescein angiographically nonsuspicious drusen. The subgroup of patients with plaques on ICG-V had a higher chance of having exudative changes develop. Indocyanine-green videoangiography may be a predictive indicator of future exudative changes in eyes with drusen. A much larger prospective study seems justified

Age-related macular degeneration, the leading cause of legal blindness in people over age 60 worldwide, represents a public health crisis that deserves the attention and understanding of all physicians. The dry form of the disease is more common than the wet, but the wet form causes the most severe vision loss. Other than vision aids (e.g., glasses, magnifiers), no treatments or preventive measures are currently available for patients with dry macular degeneration, and laser photocoagulation with fluorescein angiography is the only clinically proven therapy for neovascular disease. Indocyanine green angiography is a promising new imaging tool that may improve detection of patients likely to benefit from laser therapy. Until better diagnostic and treatment options are available, early screening and patient education offer the best hope for reducing the widespread devastation caused by this disease

BACKGROUND: Evaluation of the vasculature and blood flow in the fundus is limited by the small field of view of conventional fundus cameras. We sought to develop an easy method to image wide areas of the fundus. METHODS: Wide-angle contact fundus lenses with antireflective coatings in the infrared range were placed on the eye and indocyanine green angiography was done on the fundus through the contact lenses. More than 50 patients with varying fundus pathology have been examined. RESULTS: The angular field of view using this method can reach 160 degrees. Obtaining angiograms where the field of view extended anterior to the ora serrata was simplified, and studying the choroidal vasculature in detail was possible. In addition, imaging of entities such as peripheral choroidal neovascularization and choroidal tumors was enhanced with the present technique as compared with conventional techniques. CONCLUSIONS: Angiography through wide-angle fundus lenses is an easy and inexpensive method of visualizing large areas of the fundus. This technique may help improve our ability to image the angioarchitecture, hemodynamics, and pathologic changes in the retina and choroid

OBJECTIVE: This study aimed to determine the effect of external beam radiation therapy on choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD). DESIGN: The study design was a nonrandomized clinical trial with an historic control group. PARTICIPANTS: A total of 91 patients were treated with external beam radiation. These patients were compared retrospectively to the 119 patients in a control group. INTERVENTION: Patients with subfoveal CNV who did not meet the criteria for laser treatment defined by published reports from the Macular Photocoagulation Study Group or who did not want laser treatment were considered for radiation therapy in a nonrandomized, prospective clinical trial. Additional entry criteria for this prospective study included visual acuity better than or equal to 20/320 on the Early Treatment Diabetic Retinopathy Study chart and a lesion size less than 12 disc areas. The patients were treated with 5 fractions of 200 cGy 6 MV external beam photons. MAIN OUTCOME MEASURES: The visual acuity measured at baseline was compared to the visual acuity after 1 year of follow-up. RESULTS: The mean baseline visual acuity of the 91 patients entered into the Radiation Study was 20/80. After 1 year, 83 patients (91.2%) completed follow-up, and their mean visual acuity dropped to 20/200. By comparison, the mean baseline visual acuity of the control patients also was 20/80, and after 1 year, the control subjects had a mean visual acuity of 20/125. At 1 year of follow-up, 49.4% of patients treated with radiation and 38.1% of the control subjects lost 3 or more lines of visual acuity (P = 0.16). CONCLUSIONS: This study found that external beam radiation using 1000 cGy in 5 fractions, a dose similar to that used in previous studies, was not effective in the treatment of CNV secondary to AMD. These results suggest that patients should not be treated with this dose of external beam radiation for CNV secondary to AMD

OBJECTIVE: This study aimed to use a new technique for ocular imaging, digital subtraction indocyanine green angiography (DS-ICGA), to evaluate patients with occult choroidal neovascularization (CNV). DESIGN: The design was a cross-sectional study of patients with occult CNV. PARTICIPANTS: A total of 31 eyes of 31 patients were studied. INTERVENTION: Digital subtraction of sequentially acquired indocyanine green angiographic frames was used to image the progression of the dye front in eyes with occult CNV. A method of pseudocolor imaging of the choroid was developed that allows differentiation and identification of underlying choroidal arteries and veins. RESULTS: The DS-ICGA of occult CNV showed consistent findings. Occult CNV was imaged with greater detail and in a shorter period of time than with conventional indocyanine green angiography. The fundus landmarks were retained with DS-ICGA much better than with conventional indocyanine green angiography. CONCLUSIONS: The DS-ICGA uses time to dissect the choroidal circulation. With DS-ICGA, occult CNV could be imaged more quickly and in greater detail than with conventional imaging techniques. The DS-ICGA may improve the authors ability to image, and subsequently treat, occult CNV

BACKGROUND: Resistance to activated protein C (APC resistance) is a thrombophilic abnormality characterized by a normal plasma level of protein C and an inherited defect in the coagulative response. This condition is believed to be caused by a point mutation in factor V, the so-called factor V Leiden, and is inherited as an autosomal dominant trait. PURPOSE: A case-control study was carried out to evaluate the prevalence of APC resistance and factor V Leiden in patients with retinal vein occlusion (RVO) and in control subjects. METHODS: Eighty-four consecutive RVO patients and 70 controls were tested for APC resistance with a commercial assay (Chromogenix). The first 30 patients and 47 controls were also studied for factor V Leiden. In addition, a repeat APC-resistance test was performed in 40 RVO patients and in 9 controls with a second-generation assay done to compare the reliability and reproducibility of the tests. RESULTS: Results of testing for APC resistance with the first-generation assay revealed positive results in 38 (45%) of the study patients and 6 (9%) of the controls. The difference in frequencies of APC resistance in patients and controls was statistically significant (P < 0.0001). In the patients tested for factor V Leiden, one (3%) was a heterozygous carrier of the Arg506GIn mutation and one (2%) of the controls was a heterozygous carrier. No homozygous individuals were identified in either the study or the control groups. The difference in frequencies of factor V Leiden in study patients and controls was not statistically significant (P = 1). The repeat APC-resistance assay using factor V-deficient plasma in 40 RVO patients and 9 controls did not show any significant difference between study patients and controls or an association between APC resistance and the determination of the factor V Leiden mutant. CONCLUSION: The first-generation commercial assay for APC resistance is not a useful screening test. The molecular test for factor V Leiden is the only definitive method. Furthermore, no significant association was found between factor V Leiden and retinal vein occlusion. Accordingly, routine testing for the presence of the factor V Leiden mutant is not advisable for patients with retinal vein occlusion

OBJECTIVE: The authors evaluated the clinical, fluorescein, and indocyanine green (ICG) angiographic characteristics of the macular variant of idiopathic polypoidal choroidal vasculopathy (IPCV). DESIGN: Observational case series. PARTICIPANTS: The records, photographs, and fluorescein and ICG angiograms of eight eyes of seven patients with IPCV lesions confined to the macula were reviewed. MAIN OUTCOME MEASURES: The visual acuity, fundus examination, fluorescein and ICG angiographic characteristics, and clinical course were compared. RESULTS: All patients demonstrated polypoidal lesions arising from macular choroidal vessels on ICG angiography. One patient had bilateral lesions. These lesions appeared hyperfluorescent in the early phases of both fluorescein and ICG angiography. Late-phase leakage was seen in cases associated with subretinal fluid or exudate. None of these patients demonstrated polypoidal lesions arising from the peripapillary choroidal circulation or peripapillary choroidal neovascularization. Three eyes with polypoidal lesions that were associated with subretinal fluid and exudates were treated with photocoagulation. Five eyes were not treated. Final visual acuity ranged from 20/20 to hand motions. Severe visual loss was associated with vitreous and subretinal hemorrhage, but this resolved without permanent severe visual loss in several cases. CONCLUSIONS: In the macular variant of IPCV, ICG and fluorescein angiography demonstrate characteristic macular polypoidal lesions without evidence of peripapillary lesions. The vascular origin of these polypoidal lesions appears to be the macular choroidal circulation. This is distinguished from classic IPCV, in which lesions appear to arise from the peripapillary choroidal circulation. Visual prognosis appears to be good, with most patients retaining visual acuity of 20/80 or better. If subretinal fluid or exudates reduce visual acuity, photocoagulation should be considered

BACKGROUND: Lacquer cracks are breaks in the retinal pigment epithelial-Bruch's membrane-choriocapillaris complex and are manifestations of pathologic myopia. Progressive posterior segment elongation, uveal scleral thinning, and retinal pigment epithelial degeneration are thought to create a predisposition for crack formation in these eyes. In turn, choroidal neovascularization (CNV) may develop within the cracks to produce disciform scarring of the macula. This study examined lacquer cracks as a possible consequence of laser photocoagulation of CNV. METHODS: From the files of two retinal referral practices, five patients were located in whom lacquer cracks developed or expanded after laser photocoagulation for macular CNV in pathologic myopia. The mean age of the patients was 54.8 years. Four patients were treated with krypton red laser and one with an argon laser. Laser settings were available for only one of the patients. RESULTS: After laser photocoagulation, lacquer cracks were noted to expand in one or two directions from the laser scar between 10 days and 3 months of the treatment. The cracks also served as a pathway for progressive or recurrent neovascularization. CONCLUSIONS: Although lacquer cracks occur spontaneously in pathologic myopia, expansion, elongation, or simple development of a crack may occur as a result of laser photocoagulation of CNV. The new cracks also serve as a potential risk for recurrent neovascularization. This potential adverse complication should be considered in the management of CNV in pathologic myopia with laser treatment