The use of indocyanine green (ICG) during intraoperative internal limiting membrane (ILM) peeling is common for various macular diseases. The authors observed residual ICG after vitrectomy for high myopia-related macular diseases and found a unique pattern specific to its pathologic features.

Observational case series.

Twelve eyes of 12 patients with high myopia who had undergone vitrectomy with ICG-assisted ILM peeling were included (macular hole [MH], six eyes; MH and retinal detachment, three eyes; and myopic foveoschisis, three eyes). Patterns of residual ICG were observed in the posterior retina using the Heidelberg Retina Angiograph 2 (Heidelberg Engineering, Heidelberg, Germany) after surgery and were compared. The minimum follow-up was six months. Two control eyes of two patients without intravitreal ICG also were included in this study.

The residual ICG fluorescence was observed in all eyes except for the control eyes. The pattern of residual ICG fluorescence depended on the degree of myopic chorioretinal atrophy. In eyes with no or minimum chorioretinal atrophy, the pattern was similar to that of an idiopathic MH. The ICG pattern was unique in those with moderate or severe atrophy. A strong ICG signal was observed at the area of diffuse atrophy and at the edge of the patchy atrophy and staphyloma. No ICG fluorescence was observed inside the patchy atrophy.

Residual ICG fluorescence was observed in high myopia. ICG accumulation seems to depend on the status of the retinal pigment epithelial (RPE) underlying the posterior retina. RPE cells may play an important role in the kinetics of the residual ICG.