Recurrent Lower Retinal Detachment after Successful Vitrectomy

Abstract

The retina is the third and inner coat of the eye which is a light-sensitive layer of tissue. A retinal detachment (RD) describes the separation of neurosensory retina (NSR) from the retinal pigment epithelium (RPE). This results in the accumulation of sub retinal fluid (SRF) in the potential space between NSR and RPE. The main types of RD are rhegmatogenous, tractional, exudative and combined tractional rhegmatogenous detachment. Since first introduced by Machemer in 1971, pars plana vitrectomy (PPV) has been shown to be an effective management option for rhegmatogenous retinal detachment (RRDs). Over the last 40 years, there have been a variety of advancements in vitrectomy surgery including intraocular gases, increased vitreous cutter speeds, wide-angle viewing systems, per fluorocarbon liquids, lighted and curved instruments, and chandelier lights. These advancements improve the surgeon's ability to perform a thorough evaluation of the peripheral retina with high magnification and excellent illumination, which is crucial in detecting and treating all retinal breaks and relieving the vitreoretinal traction. Primary pars plana vitrectomy is still flawed by a relatively high primary re detachment rate following the initial procedure. The advantages of the technique are a high final reattachment rate and relatively good functional results in a subset of patients with more complicated types of RRD. The most common reason for redetachment in silicone oil-filled eyes is Proliferative Vitreoretinopathy (PVR), and it occurs in approximately 80% of the affected eyes. The redetachment could be because of a leaking retinal break in the far periphery, mostly inferior, and therefore not supported by the oil globule, with no PVR. In some eyes, the retina comes off because of an intrinsic retinal contraction with no obvious preretinal or subretinal proliferation. Recurrent retinal detachment is a common occurrence following vitrectomy combined with silicone oil injection in the treatment of PVR. This redetachment is most often in the inferior retina. Various methods of management have been advocated, ranging from the injection of additional silicone oil to repeated membrane peeling with retinotomy. In absence of PVR the flattening of the lower retina was observed with face down positioning. If the retina flattened completely, several raws of laser were used to surround the break and the patient was asked to continue the face down position until the laser marks began to darken. Scleral buckle only reserved for small lower breaks with no PVR to improve their contact and tamponade with the silicone oil bubble. Cryo is added around the break. In recurrent cases with PVR, some surgeons operate under silicone oil. Others, however operated in all cases after silicone oil removal. Their surgical technique included evacuation of silicone oil, Traimcinolone Acetate (TA) assisted search for residual posterior cortical vitreous, epiretinal membrane peeling, stabilization of posterior retina with perflourocarbon liqid (PFCL), excision and dissection of basal vitreous gel and peripheral membranes, retinotomy/retinectomy (180 – 360 degrees), removal of subretinal proliferation, complete retinal reattachment with PFCL, endolaser and finally direct PFCL/Silicone oil exchange.