Comparisons of focal macular electroretinograms after indocyanine green-, brilliant blue G-, or triamcinolone acetonide-assisted macular hole surgery

Abstract

To compare the effects of indocyanine green (ICG)-, brilliant blue G (BBG)-, or triamcinolone acetonide (TA)-assisted internal limiting membrane (ILM) peeling during macular hole (MH) surgery on the different components of the focal macular electroretinograms (fmERGs). Forty-eight eyes of 48 patients with a macular hole were randomly divided into those undergoing ICG-, BBG-, or TA-assisted vitrectomy (n = 16 for each group). All patients had combined cataract and macular hole surgery with ILM peeling. The fmERGs were recorded before, and 1, 3, 6, 9, and 12months postoperatively. The amplitudes and implicit times of the a- and b-waves, the amplitudes of the sum of the oscillatory potentials (ΣOPs), and the photopic negative responses (PhNRs) were analyzed. The amplitudes of all of the components of the fmERGs gradually increased with time after surgery (P < 0.005). The implicit times of the a- and b-waves were significantly prolonged at 1month (P < 0.01) and then gradually returned to the baseline times. No significant differences were found in these changes among the groups. In pooled data from the 48 patients, the PhNR amplitude increased more than the a- and b-waves and the ΣOPs amplitudes at every time point after 3months (P < 0.005). The lack of significant differences on the different components of the fmERGs indicates that none of the three agents was toxic to the macula. After closure of a MH, the function of the retinal ganglion cells may recover more than that of the other neural elements in the macular area.