Rhegmatogenous retinal detachment occurs when a retinal break (or multiple breaks) allows ingress of fluid from the vitreous cavity into the subretinal space. Breaks can be atrophic, often associated with lattice degeneration, or they may be tractional tears, related to vitreous traction on the retina and posterior vitreous detachment (PVD). The risk of rhegmatogenous retinal detachment (RRD) in otherwise normal eyes is approximately 5 new cases in 100,000 persons per year; lifetime risk is approximately 1 in 300 persons. The most significant risk factors are high myopia, family history of retinal detachment, and fellow-eye retinal detachment. Pseudophakia is also an important risk factor; the reported incidence after cataract surgery is less than 1% but increases over time (Fig 20-13). Patient characteristics that increase the risk of pseudophakic retinal detachment include younger age at the time of cataract extraction, male sex, and longer axial length. A surgical complication such as posterior capsular rupture with vitreous loss has been estimated to increase the risk of retinal detachment by as much as 20-fold.
Selection of the treatment approach among the modalities available for retinal detachment is surgeon-dependent and remains a topic of debate among retinal surgeons. The precise configuration of the detachment, the location of the breaks, and the phakic status of the eye are all considered carefully before the method of treatment is determined.
Techniques for Surgical Repair of Retinal Detachments
There are 3 surgical techniques for eyes with primary uncomplicated rhegmatogenous retinal detachment: pneumatic retinopexy, scleral buckling, and primary vitrectomy with or without scleral buckling. The common goals of these procedures are to identify and treat all causative retinal breaks while supporting such breaks through external and internal tamponade as needed.
Kreissig I, ed. Primary Retinal Detachment: Options for Repair. Berlin: Springer-Verlag; 2005.
Campo RV, Sipperley JO, Sneed SR, et al. Pars plana vitrectomy without scleral buckle for pseudophakic retinal detachments. Ophthalmology. 1999;106(9):1811–1816.
Pneumatic retinopexy closes retinal breaks by using an intraocular gas bubble for a sufficient time to allow the subretinal fluid to reabsorb and a chorioretinal adhesion to form around the causative break(s). The classic indications for pneumatic retinopexy include
confidence that all retinal breaks have been identified
retinal breaks that are confined to the superior 8 clock-hours
a single retinal break or multiple breaks within 1–2 clock-hours
the absence of proliferative vitreoretinopathy (PVR) grade CP or CA
a cooperative patient who can maintain proper positioning
With direct pneumatic occlusion of the causative retinal breaks in acute detachments, subretinal fluid is often completely reabsorbed within 6–8 hours.
Transconjunctival cryopexy can be performed on the causative retinal breaks; alternatively, laser retinopexy may be performed after retinal apposition. A variety of intraocular gases (eg, air, SF6, C3F8) can be used for tamponade, and a concomitant anterior chamber paracentesis is generally required to normalize the elevated IOP that results from the gas injection. The patient must maintain a predetermined head posture to place the breaks in the least dependent position (Fig 20-14).
A prospective, multicenter, randomized clinical trial comparing pneumatic retinopexy with scleral buckling demonstrated successful retinal reattachment in 73% of patients who underwent pneumatic retinopexy and in 82% of those who received scleral buckle procedures; this difference was not statistically significant. Complications from pneumatic retinopexy include subretinal gas migration, anterior chamber gas migration, endophthalmitis, cataract, and recurrent retinal detachment from the formation of new retinal breaks.
Gilca M, Duval R, Goodyear E, Olivier S, Cordahi G. Factors associated with outcomes of pneumatic retinopexy for rhegmatogenous retinal detachments: a retrospective review of 422 cases. Retina. 2014;34(4):693–699.
Tornambe PE, Hilton GF; The Retinal Detachment Study Group. Pneumatic retinopexy. A multicenter randomized controlled clinical trial comparing pneumatic retinopexy with scleral buckling. Ophthalmology. 1989;96(6):772–784.
Scleral buckling closes retinal breaks through external scleral indentation. Transscleral cryopexy is used to create a permanent adhesion between the retina and RPE at the sites of retinal breaks. The buckling material is then carefully positioned to support the causative breaks by scleral imbrication.
Figure 20-14 Schematic of pneumatic retinopexy. A, A small, expansile gas bubble is injected into the vitreous cavity. B, The bubble enlarges. The patient is positioned so the gas bubble occludes the retinal break, allowing for resorption of subretinal fluid.
(Illustration by Dave Yates.)
The surgeon chooses the scleral buckling technique (eg, encircling, segmental, or radial placement of the sponge, sutured vs scleral tunnels) according to the number and position of retinal breaks, eye size, and associated vitreoretinal findings (eg, lattice degeneration, vitreoretinal traction, aphakia), and individual preference and training (Video 20-8, Fig 20-15).
Scleral buckle for rhegmatogenous retinal detachment.
Courtesy of Colin A. McCannel, MD.
An increase in the IOP related to compression from the buckling effect may indicate the need for external drainage of the subretinal fluid, anterior chamber paracentesis, or both. Chronic viscous subretinal fluid, “fish-mouthing” of large retinal breaks, and bullous retinal detachments may necessitate treatment with intraocular gas tamponade, drainage, or both. Complications of scleral buckling include induced myopia, anterior ocular ischemia, diplopia, ptosis, orbital cellulitis, subretinal hemorrhage from drainage, and retinal incarceration at the drainage site.
Figure 20-15 Scleral buckle procedure. The conjunctiva is opened; the rectus muscles are isolated and tagged with a “0” silk suture. A, The eye is rotated so the sclera is exposed. Using calipers, the surgeon measures and marks the location for the anterior and posterior scleral pass for the radial mattress suture. B, C, The posterior scleral suture pass is accomplished. D, E, The encircling element, a 506 sponge, is passed, using forceps, under the suture and rectus muscle. F, The scleral buckle is fully installed; the tied-up radial mattress suture is shown with the knot rotated posteriorly.
(Courtesy of Colin A. McCannel, MD.)
Traction on focal areas of adhesion of the vitreous to the peripheral retina (frequently at the posterior vitreous base insertion) may cause retinal breaks, allowing intraocular fluid to migrate into the subretinal space, which leads to retinal detachment. Consequently, the goals of primary vitrectomy are to remove cortical vitreous adherent to retinal breaks, directly drain the subretinal fluid, tamponade the breaks (using air, gas, or silicone oil), and create chorioretinal adhesions around each retinal break with endolaser photocoagulation or cryopexy.
In general, the 3-port vitrectomy technique is used, employing 20-gauge, 23-gauge, 25-gauge, or 27-gauge instruments. At the surgeon’s discretion, vitrectomy can be combined with a scleral buckle procedure. During vitrectomy, a complete posterior vitreous separation is ensured, and the peripheral cortical vitreous is carefully shaved toward the vitreous base to relieve traction on the retinal breaks (Video 20-9, Fig 20-16). To drain the subretinal fluid and achieve intraoperative retinal reattachment, the surgeon can use either an intentional drainage retinotomy or perfluorocarbon liquid technique. If PVR is present, it may be necessary to peel the epiretinal (and, less commonly, subretinal) membranes to facilitate the retinal reattachment. For extensive PVR, a relaxing retinotomy or retinectomy may be required. Once the retina is flattened, chorioretinal laser photocoagulation or cryopexy can be applied. Postoperative tamponade is generally provided by intraocular air or nonexpansile concentrations of SF6 or C3F8 gas, although in complex cases the use of silicone oil may be required. Complications of vitrectomy for retinal detachment include postvitrectomy nuclear sclerosis (in phakic eyes), glaucoma, PVR, and retinal redetachment.
Vitrectomy for rhegmatogenous retinal detachment.
Courtesy of Colin A. McCannel, MD.
Figure 20-16 Vitrectomy schematic. A, Surgeon’s view of a 20-gauge, 3-port pars plana vitrectomy. B, A cross-sectional view shows an infusion cannula, endoillumination probe, and vitrectomy cutting probe.
(Illustration by Dave Yates.)
Complex retinal detachment includes giant retinal tears, recurrent retinal detachment, vitreous hemorrhage, and PVR. The surgeon must use pars plana vitrectomy techniques in order to address the common features of PVR, including proliferative membranes, retinal folds, and media opacities (see Chapter 16). In the past, controversy surrounded the use of long-acting gas versus silicone oil in retinal tamponade for eyes with complex retinal detachment caused by advanced grades of PVR. This issue was addressed in the Silicone Study, a prospective, multicenter, randomized study, which concluded that tamponade with SF6 was inferior to long-term tamponade with either C3F8 or silicone oil. Differences in outcomes from the use of C3F8 and silicone oil were statistically insignificant; however, patients treated with silicone oil experienced a lower rate of hypotony than those treated with C3F8.
Vitrectomy with silicone oil or sulfur hexafluoride gas in eyes with severe proliferative vitreoretinopathy: results of a randomized clinical trial. Silicone Study report 1. Arch Ophthalmol. 1992;110(6):770–779.
Vitrectomy with silicone oil or perfluoropropane gas in eyes with severe proliferative vitreoretinopathy: results of a randomized clinical trial. Silicone Study report 2. Arch Ophthalmol. 1992;110(6):780–792.
Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.