Fluorescence imaging of the ILM flap following MH surgery

Abstract

Purpose: To report on the imaging of internal limiting membrane (ILM) flap following macular hole (MH) surgery.

Observations: Three eyes of 3 patients with baseline Snellen visual acuities (VAs) of 20/250, 20/30, and 20/100 underwent superior wide-base internal limiting membrane flap transposition (SWIFT) for MH. Indocyanine green (ICG) was used for intraoperative staining of the ILM. Following MH surgery, MH closed in all cases and VAs were 20/30, 20/30, and 20/60 respectively. An "en face" ICG fluorescence image of the ILM flap was obtained using infrared confocal scanning laser imaging at 795 nm. ICG fluorescence demonstrated the ILM flap to be intact and in good position with complete coverage of the MH in all cases. An area of hypofluorescence was present superiorly, corresponding to the flap harvest site with absent ILM. ICG hyperfluorescence of varying intensity was present at the MH site in all 3 cases. Folding of the ILM flap was present in one case.

Conclusions and importance: Following MH surgery, the status of an ILM flap may be evaluated by an "en face" image of the flap obtained by ICG fluorescence imaging. This imaging modality may be valuable in the study of various ILM flap techniques.

Keywords: Indocyanine green (ICG) fluorescence; Internal limiting membrane (ILM) flap; Macular hole; Vitrectomy.