Ultrastructure of the vitreoretinal interface following the removal of the internal limiting membrane using indocyanine green

Abstract

Purpose. To investigate the morphological changes of the vitreoretinal interface following the removal of the internal limiting membrane (ILM) using indocyanine green (ICG). Methods. In 10 primate eyes, a pars plana vitrectomy was performed followed by ICG-assisted peeling of the ILM. Morphological changes in the exposed inner surface of the retina were investigated by electronmicroscopy immediately, 3, 6 and 12 months after the ILM removal. Results. The excised ILM was associated with fragments of glial tissue. The Muller cell processes were damaged and removed at the corresponding region of the retina. Regenerative spindle-shaped Muller cell processes were observed focally showing a meshwork like configuration at 3 and 6 months. Flattened and stretched processes were observed at 12 months; however, there was no apparent ILM regeneration. Conclusions. ICG assisted ILM peeling was observed to cause mild damage to the vitreoretinal interface, which did not completely recover within 12 months.