Effect of different surgical methods on secondary macular epiretinal membrane

Objective To observe the effect of different surgical methods for secondary macular epiretinal membrane. Methods The clinical data of 76 patients (76 eyes) with secondary macular membrane surgery in the Department of Ophthalmology of Baoding First Central Hospital from January 2014 to January 2017 were retrospectively analyzed. According to the different methods of treatment, all patients were divided into non union group and combined group. The non joint group was A group and the combined group was B group. In group A, 38 cases (38 eyes) were treated with vitrectomy with three incision of ciliary body combined with macular anterior membrane stripping and internal boundary membrane stripping. 38 cases (38 eyes) in group B were treated with vitrectomy with three incision of ciliary body combined with macular anterior membrane stripping and internal boundary membrane stripping, and intravitreal injection of triamcinolone acetonide. The best corrected visual acuity (BCVA), macular morphology and operative complications before and after operation were followed up. The visual acuity of the patients before and after operation was described with the median (max-mini). The comparison of visual acuity before and after operation was made by paired Mann-Whitney U test. The visual improvement was described by the number of eyes and percentage, and the Kruskal-Wallis H rank and test were used in the group. The thickness of the central neuroepithelial layer (CMT) before and after operation was described with mean standard deviation(±s). The comparison between the groups before and after the operation and the comparison between the groups before and after the operation were compared with the paired t-test. Results All patients were followed up for 3~12 month with an average of (6.3±2.4) month. In group A, BCVA was increased in 25 cases (25 eyes), 11 cases (11 eyes) remained unchanged, and 2 cases (2 eyes) decreased. There was a significant difference in BCVA after operation compared with that before operation (u=4.251, P 0.05). The average thickness of CMT in group A was (336.87±123.18) μm before operation, and (295.17±90.23) μm after operation. The difference of CMT before and after operation was statistically significant (t=5.43, P<0.05). The average thickness of CMT in group B was (321.18 ±132.12) μm before operation, and (245.15±79.64) μm after operation. The difference of CMT before and after operation was statistically significant (t=4.89, P<0.05). The difference was statistically significant (t=-2.51, P<0.05) between the two groups after the operation (t=-2.51, P<0.05). The results showed that the improvement of CMT thickness in group B was faster than that in group A. Group A had 3 cases (3 eyes) with peripheral traction small holes, 1 case (1 eye) recovered after laser treatment, and 2 cases (2 eyes) reoperation. In group B, 2 cases (2 eyes) with peripheral traction small holes were treated by laser. During the follow-up period, 4 patients (4 eyes) in group A had recurrent anterior membrane. Conclusions Two surgical approaches can effectively treat secondary macular epiretinal membrane. Among them, operation in group B can improve CMT and reduce the recurrence of macular epiretinal membrane. Key words: Secondary macular membrane; Denudation of inner boundary membrane; Intravitreous intravitre injection; Triamcinolone acetonide