Confocal tomographic angiography with ICG of the optic nerve head

Purpose. Confocal tomographic angiography is a new method for evaluating the blood supply of the optic nerve head (ONH). This technology combines the confocal laser scanning ophthalmoscopy with indocyanine green (ICG) angiography, into one system. Demonstration of the superficial and deep vessels of the ONH is feasible by CTA through optical sectioning of the ONH. The system was tested in glaucoma patients in an attempt to correlate alterations in blood supply of the ONH with visual field defects. Methods. CTA was performed in 50 glaucomatous and 20 non glaucomatous patients. Results. In normal discs a diffuse microvascular filling pattern of the disc area was apparent with no filling defects. However, a filling defect confined to the damaged zone was found in eyes with localized notching of the optic nerve. In eyes with severe glaucomatous damage some remaining deep laminar vessels were detected but no microvascular pattern was evident. Various types of visual field defects could be correlated with the location of vascular damage in the ONH. Conclusions. CTA can successfully demonstrate compromised vascular zones at the ONH in glaucoma with correlation to visual field defects.