Purpose: To observe the persistence of infrared fluorescence after indocyanine green (ICG)-assisted vitrectomy.
Methods: Eighteen consecutive patients underwent ICG-assisted vitrectomy for eyes with macular holes, epiretinal membranes, diabetic macular edema, and macular edema due to retinal vein occlusion. The internal limiting membrane was peeled after staining with 0.42% ICG solution. Postoperative observation of fundus infrared fluorescence was carried out using Heidelberg Retina Angiography (Heidelberg, Germany).
Results: Within a few months after surgery, intense fluorescence was observed around the macular hole and on the optic disk, photocoagulation scars, and the optic nerve fiber and was especially strong in the area along the vascular arcade. At the final visit (16-36 months after surgery), 12 (67%) of 18 eyes had infrared fluorescence that included fluorescence corresponding to the macular hole, retinal edema, and photocoagulation scars. The fluorescence over chorioretinal atrophy in a highly myopic eye disappeared compared with the area having an intact retinal pigment epithelium.
Conclusions: Infrared fluorescence from ICG persists for 16 months to 36 months after ICG-assisted vitrectomy. ICG introduced directly into the vitreous cavity may remain in the eye over years. Careful long-term observation for the adverse effects of ICG is needed.