Treatment of retinal detachment of the pseudophak: vitrectomy without episcleral indentation versus ab externo surgery

Several factors predispose to the occurrence of rhegmatogenous retinal detachment, including cataract surgery, myopia, and degenerative lesions of the peripheral retina as well as eye trauma. This study aims to compare the anatomical and functional outcome of the two surgical techniques (AB interno vs AB externo) in our Hospital. We conducted a descriptive, retrospective study in the Department of Ophthalmology at the University Hospital Mohamed VI in Marrakech, over a period of 3 years, ranging from January 2013 to December 2015. During the study period we compared two groups of people: the first group undergoing surgery by an external approach (cryoapplication of the dehiscences with episcleral indentation) while the second undergoing surgery by endo-ocular approach. Group A or AB externo group included 26 eyes (26 patients) while Group B or vitrectomy with internal tamponade group included 22 eyes (22 patients). In the AB externo group, the average age was 54.92 years against 51.64 years in the AB interno group, with a slight predominance of males in both groups. After the first surgery, retinal reapplication was obtained in both groups with no significant difference, (about 80.76% in Group A versus 81.82% of the second group). In both groups failure was caused advanced vitreoretinal proliferation (4 cases), de novo breaks (3 cases) and breaks which had not been detected on first examinations (2 cases). All these cases underwent reoperation by AB interno approach: patients of group A underwent complete vitrectomy with revision of the indentation +/- internal limiting membrane peeling with internal gas tamponade while patients of group B underwent complementary vitrectomy with dissection of proliferative vitreoretinopathy (PVR) and an internal tamponade with silicone oil. After a mean follow-up period of 12 months, there was no significant difference in visual acuity between the 2 groups, with more than one third of the patients who had regained visual acuity between 1/10 and 5/10 (about 34,61% in AB externo group and 36,36% in AB interno group). Given the technological advances in vitrectomy, the current trend is the endoocular surgery however ab-externo surgery is mainly used in the treatment of retinal detachment with visible breaks which can be easily treated with indentation without advanced vitreoretineal proliferation (PVR A-B).