Persistence of Retinal Staining After ICG-Assisted Vitrectomy for Full Thickness Macular Hole (FTMH) and epiretinal Membrane

Abstract

Abstract: : Purpose: It has been shown that ICG staining persists after ILM peeling during ICG-assisted vitrectomy. The aim of this study was to determine the characteristics of the staining using different concentrations and different media. Methods: We studied 74 consecutive patients (34 M and 40 F: a total of 79 eyes) between October 2001 and August 2002: 29 had stage 2-4 macular holes, two a macular hole associated with retinal detachment, and 43 epiretinal membranes. All of them underwent vitrectomy and ICG-assisted ILM peeling; five patients were reoperated because of primary surgical failure. During the first five months, we used 0.3 ml of ICG solution at a concentration of 0.25 %, diluted in 1 ml of distilled water and 9 ml of BSS, after which the dye concentration was progressively decreased to 0.125%, 0.06% and 0.05%: the solutions were left in the vitreous cavity for ten seconds and then completely washed out. Healon was used as the medium in three cases, autologous serum in one, and Healon Five (administered directly above the hole in order to protect the PRE) in one. The pre- and post-operative photographs were taken using a Heidelberg Retinal Angiograph (infra-red diode laser at 830 nm; infra-red 795 nm for ICGA with barrier filter at 810 nm; red-free and blue filter for autofluorescence). Results: Follow-up images were taken immediately after surgery, and within the first 15 days (51 patients), and after one month (29 patients), three months (24 patients) and six months (22 patients). All of the patients showed widespread retinal staining in the 795 nm infra-red images, even when Healon was used as the solvent and seemed to be intraoperatively "stable" at the injection site. After three months, there were no differences in retinal staining between the various dye dilutions or media; after six months, the dye seemed to concentrate on the optic disk (as previously reported by Tadayoni et al.). Conclusion: ICG staining remains on the retinal surface for six months after surgery regardless of the dye concentration or medium, but its pattern is different after the third month.

Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, S • macular holes • vitreoretinal surgery