Staining of the ILM in macular surgery

We read with interest the article by Li and colleagues about trypan blue staining of the vitreomacular interface during vitrectomy.1 We congratulate the authors on their work. In particular, we appreciate their critical approach of testing trypan blue for staining of the internal limiting membrane (ILM) and epiretinal membrane (ERM) as well as their comments on potential untoward effects of indocyanine green (ICG) in macular surgery. We would like to comment on two remarks concerning the ultrastructural findings on the retinal side of the ILM following ILM removal with and without the use of ICG. We agree with Li and colleagues that fragments of glial cells are commonly found in ILM specimens. Ultrastructurally, they appear as tiny fragments of Muller cell membranes adherent to and enclosed within the undulations of the retinal side of the ILM. These glial structures had been described in detail by Eckhardt and colleagues, and are in accordance with previous work of our group, in an investigation of the ultrastructure of the vitreomacular interface …