Faculty Bibliography

BACKGROUND: Occult choroidal neovascularization (CNV) secondary to age-related macular degeneration occurs in the majority of patients with exudative maculopathy. Since occult CNV cannot be imaged clearly by fluorescein angiography, this condition is untreatable. The authors performed digital indocyanine-green videoangiography (ICG-V) on 657 consecutive eyes with occult CNV by fluorescein angiography to determine if this technique could be useful in enhancing the imaging of the neovascularization, and thus increasing treatment eligibility. MATERIALS AND METHODS: Six hundred fifty-seven consecutive eyes with occult CNV were studied. The fluorescein and ICG angiograms were compared, and the percentage of patients potentially eligible for laser therapy based on ICG findings was calculated. RESULTS: Of 413 eyes with occult CNV without pigment epithelial detachments, focal areas of neovascularization were noted in 89 (22%). Overall, 142 (34.3%) eyes had lesions that were potentially treatable by laser photocoagulation based on additional information provided by ICG-V. Of the 235 eyes with occult CNV and vascularized pigment epithelial detachments, 98 (42%) were eligible for laser therapy based on ICG-V findings. The authors calculate that ICG-V enhances the treatment eligibility by approximately one third. CONCLUSIONS: In diagnosing occult CNV, ICG-V is an important adjunctive technique to fluorescein angiography. This technique is especially useful in delineating occult neovascularization, neovascularization with overlying subretinal hemorrhage or serosanguineous fluid, and neovascularization associated with pigment epithelial detachments. The authors currently suggest that ICG-V be performed in eyes in which well-delineated neovascularization cannot be identified by fluorescein angiography. Based on their preliminary study, it can be expected that one in three patients with occult CNV potentially will be eligible for laser photocoagulation based on ICG-V. Further studies are necessary to confirm these findings

BACKGROUND: The pathogenesis of central serous chorioretinopathy (CSC) is poorly understood. Abnormalities in the choroidal circulation have been hypothesized to be causative factors. Fluorescein angiography has not been particularly useful in identifying specific choroidal defects in CSC, largely because of inherent limitations in imaging with this technique. Recent technologic advances in digital indocyanine green videoangiography allow enhanced imaging of the choroid and other subretinal structures in comparison with fluorescein angiography. METHODS: We performed digital indocyanine green videoangiography in 29 consecutive eyes with CSC and compared our results with clinical and fluorescein angiographic findings. RESULTS: Several newly recognized subretinal abnormalities in CSC were noted with digital indocyanine green videoangiography, including (1) presumed hyperpermeability of the choroidal circulation surrounding active retinal pigment epithelial leaks, (2) additional focal and multifocal areas of presumed choroidal hyperpermeability not associated with abnormalities detectable by fluorescein angiography or clinical examination, and (3) multiple presumed 'occult' serous retinal pigment epithelial detachments with a characteristic indocyanine green videoangiographic pattern. CONCLUSION: We suggest that the pathogenesis of CSC may be due to a choroidal vascular hyperpermeability with and without associated active pigment epithelial leaks and multiple presumed 'occult' serous retinal pigment epithelial detachments. Based on these findings, a hypothetical model can be constructed related to the pathogenesis of CSC, beginning with choroidal abnormalities that secondarily affect the retinal pigment epithelium and neurosensory retina

Indocyanine-green (ICG) angiography has experienced a rejuvenated interest in the past few years because of improvements in technological systems. After three years of experience with evolving digital technology, we have reviewed our experience to provide an update on potential applications in a variety of choroidopathies. Based on 3,000 cases studied with ICG angiography, we evaluated the diagnostic value of the procedure in choroidal abnormalities including ischemic, tumor, idiopathic, inflammatory, and neovascularized diseases. ICG angiography is still of limited clinical value in ischemic diseases because of a relatively poor imaging potential for the choriocapillaris. The procedure has not yet provided information which is of significant value in the evaluation and management of choroidal tumors. Valuable information has been provided on the fundamental pathogenesis of certain idiopathic diseases. Preliminary experience in inflammatory diseases is very promising. A genuine advance in imaging of 'occult'-choroidal neovascularization has been provided by the diagnostic technique. Improved delineation of these vessels offers opportunities for ICG-guided laser treatment