Decreased retinal sensitivity after internal limiting membrane peeling for macular hole surgery

Abstract

Aims: To compare the retinal sensitivity and frequency of microscotomas found by spectral domain optical coherence tomography (SD-OCT) combined with scanning laser ophthalmoscopy (SLO) microperimetry after idiopathic macular hole closure, in eyes that underwent internal limiting membrane (ILM) peeling and eyes that did not.

Methods: This was a retrospective, non-randomised, comparative study. Combined SD-OCT and SLO microperimetry was performed in 16 consecutive eyes after closure of an idiopathic macular hole. A customised microperimetry pattern with 29 measurement points was used. The ILM was peeled in 8/16 eyes. The main outcome measure was mean retinal sensitivity.

Results: Mean retinal sensitivity (in dB) was lower after peeling: 9.80 ± 2.35 dB with peeling versus 13.19 ± 2.92 without (p=0.0209). Postoperative microscotomas were significantly more frequent after ILM peeling: 11.3 ± 6.6 points with retinal sensitivity below 10 dB in eyes that underwent peeling versus 2.9 ± 4.6 in those that did not (p=0.0093).

Conclusions: These results suggest that ILM peeling may reduce retinal sensitivity, and significantly increase the incidence of microscotomas. Until a prospective trial confirming or not these results, it seems justified to avoid peeling the ILM when its potential benefit seems minor or unproved, and when peeling is carried out, to limit the surface peeled to the bare minimum.

Figure 1

Scanning laser ophthalmoscope microperimetry image with superimposed location of the patient's fixation (blue crosses) after idiopathic macular hole surgery. (Left) At 1 month after surgery without internal limiting membrane (ILM) peeling: normal retinal sensitivity and no deep microscotomas in the central 9° of the visual field in this eye. (Right) At 2 months after surgery with ILM peeling: decreased mean retinal sensitivity, deep absolute microscotoma and relative microscotomas in the central 9° of the retina of this eye. This figure is only reproduced in colour in the online version.