[Confocal indocyanine green angiography with 3-dimensional topography. Results in choroid neovascularization (CNV)]

Confocal indocyanin green angiography (ICGA) offers detailed two-dimensional imaging of choroidal pathologies. However, the spatial extension of lesions is not reproduced. We developed a novel method for three-dimensional documentation of choroidal vascular abnormalities.

Focal series were performed using a laser scanning ophthalmoscope (Heidelberg Retina Angiograph). Thirty-two images within a distance of 4 mm were taken at a frequency of 20 Hz. Following correction of dislocation, a surface of normalized fluorescence intensity was determined and displayed topographically.

In physiological eyes three-dimensional ICGA demonstrates the homogeneous concavity of the choroid with prominent overlay of retinal vessels. Classic choroidal neovascularization (CNV) imposes as substantial elevation. Occult CNV are demarcated despite negative conventional ICGA due to reduction of blocking phenomena. Therapeutic interventions such as photocoagulation, photodynamic therapy and surgery induce a resolution of CNV with or without residual defects within the choroidal pattern.

Topographic ICGA allows for the first time in-vivo representation of prominence and depth of vascularized pathologies and provides a tool for improved diagnostic and therapeutic evaluation.