Abstract
Abstract: :
Purpose: The toxicity of ICG dye which is applied directly to the vitreous cavity is controversial. The persistence of ICG dye in intraocular tissue after surgery might be important for toxicity. In this study, the persistence of ICG dye in the eye after intravitreal administration was documented. Methods: 16 eyes of 17 patients with different etiologies (idiopathic macular hole and chronic macular edema) were enrolled in the study. After the pars plana vitrectomy and removal of the posterior hyaloid, total fluid-air exchange was performed and 0.1 millilitre of 0.25% ICG solution was injected into the vitreous cavity. Following a waiting period of one minute, the ICG solution was removed and the vitreous cavity re-filled with fluid. Then the green stained ILM in the macular area was peeled. During the follow-up period, ICG fluorescence was searched for with 795nm ICG fundus camera at intervals varying from 1 week to 12 months postoperatively. The fellow eyes of 16 patients were taken as a control group. Results: In 83 % of the eyes ICG fluorescence images were documented even 12 months after surgery. Four different fluorescence patterns were found such as posterior pole diffuse, posterior pole scattered fluorescence, major vascular arcade fluorescence and optic nerve head ICG fluorescence. Posterior pole diffuse fluorescence was documented in all eyes only in the first postoperative week. Posterior pole scattered fluorescence corresponding with old laser photocoagulation spots was documented in the first 3 months postoperatively. However, ICG fluorescence on the major vascular arcade persisted longer and in 20% of the eyes ICG fluorescence was still recorded at 6 months postoperatively. The longest period of ICG fluorescence was documented on the optic nerve head and in 83% of the eyes ICG fluorescence was still recorded at 12 months postoperatively. On the control eyes no ICG fluorescence was recorded during the same periods. Conclusions: In this study, short contact of 0.25% ICG solution with the retina was found to produce a very long period of persistence of ICG dye on the major vascular arcade and optic nerve head. We assume that the ICG dye which remains in the eye postoperatively can be an important factor for long-term toxicity.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, S • drug toxicity/drug effects • macula/fovea