Abstract:AIM: To compare visual outcomes, central foveal thickness(CFT), and postoperative complications after vitrectomy and internal limiting membrane(ILM)peeling, with balanced salt solution(BSS)or gas tamponade, for the treatment of idiopathic macular epiretinal membrane(IMEM).
METHODS: Retrospective clinical study. 44 patients with IMEM were included in this study. All patients had undergone vitrectomy and ILM peeling. Eyes were divided into two groups: 20 eyes in group A with BSS tamponade. 24 patients in group B with gas tamponade(11 eyes were injected with filtered air and 13 eyes with perfluoropropane,100mL/L C3F8). The follow-up period was 12-16(mean 13)months. The following parameters were collected and compared: best-corrected visual acuity(BCVA)and CFT(at baseline and 1, 3, 6 and 12 months postoperatively), intraocular pressure(IOP)(at baseline and on the 1th,7th day, 1, 3 months postoperatively).
RESULTS: BCVA significantly improved, and 29 of 44 eyes(65.9%)achieved visual recovery≥0.2 logMAR. There were no significant differences between group A and group B in mean baseline logMAR BCVA(0.53±0.18 vs 0.52±0.14; P>0.05)and final logMAR BCVA(0.31±0.14 vs 0.28±0.09; P>0.05). With respect to OCT parameters, the mean CFT at 12 months(285.25±70.07μm)was significantly decreased from that of the baseline(407.82±97.00μm),(Z=4.29, P<0.05). There were no significant differences between group A and group B in mean baseline CFT(409.45±108.40μm vs 406.46±88.76μm; P>0.05)and final CFT(287.60±66.94μm vs 283.29±73.95μm; P>0.05). With respect to IOP, there were no significant differences between group A and group B at mean baseline and on the 7th day, 1, 3 months postoperatively(P>0.05). The IOP in group A was significant lower at 1th postoperative day compared with group B(Z=3.12, P<0.05), but the mean IOP of both groups were within normal range(10-21mmHg). Patients in group B with filtered air tamponade were instructed to maintain a prone position for 1 to 3 days and with perfluoropropane tamponade instructed to maintain a prone position for at least 1 week, however, patients in group A were not.
CONCLUSION: Vitrectomy and ILM peeling can significantly improve the visual acuity and decrease the CFT no matter with gas or with BSS tamponade, there were no significant differences in clinical outcomes, but it is neither necessary for patients with BSS tamponade to maintain a prone position nor have physically and psychological burden compared to who with gas, which makes surgery more efficient and safe.
