Abstract
Abstract: :
Purpose: To evaluate macular function before and after surgical closure of idiopathic macular hole using multifocal Electroretinogram(mfERG) Methods: The mfERGs were performed on seven patients, who was diagnosed as idiopathic macular hole, before and after vitrectomy(average 2.2mo) and gas(C3F8) injection. VERIS system(EDI, San Mateo, Ca)was used to record the mfERGs. The central 30 degrees of ocular fundus were stimulated by an array of 103 hexagonal elements for 4 minutes. The responses of six concentric rings (ring1 to 6) radiating from the foveal center were averaged. Preoperative responses of mfERG were compared with postoperative responses. Statistical differences were analyzed with the paired sample t–test. Results: N1, P1 and N2 amplitudes of ring1 and 2 were increased after surgery significantly. N1, P1 and N2 latencies were decreased after surgery, but these results were not significant. Average P1 amplitude of ring 1 was 23.37nV, ring 2 was 22.0nV before surgery, 34.73nV and 29.23nV after surgery.(P<0.05) Average P1 latency of ring 1 was 32.23ms, ring 2 was 30.69ms before surgery, 29.49ms and 30.58ms after surgery(P>0.05). The changes of mfERG responses were not correlated with the changes of visual acuities after surgery. Visual acuity was improved on five patients and the others were decreased; One developed RPE degeneration and another cataract. Conclusions: The mfERG responses were improved after macular hole surgery. These results suggest that mfERG may be an useful method to assess macular function changes after macular hole surgery, although the responses were not correlated with the visual acuities.
Keywords: macular holes • electroretinography: clinical • vitreoretinal surgery