Rhegmatogenous Retinal Detachment with a High Risk of Proliferative Vitreoretinopathy Treated with Episcleral Surgery and an Intravitreal Dexamethasone 0.7-mg Implant Open Access

Proliferative vitreoretinopathy (PVR) is the most common cause of failure in retinal detachment surgery [1]. It can occur in untreated eyes or after pneumatic retinopexy, cryotherapy, laser retinopexy, scleral buckling or vitrectomy [2,3]. PVR is a reparative process, similar to a keloid, initiated by full- or partial-thickness retinal breaks, retinopexy, and other types of retinal damage. It can occur from glial or retinal pigment epithelium (RPE) proliferation. Glial or RPE cells migrate to one or both surfaces of the retina, then migrate further and cover the posterior surface of the detached posterior hyaloid face [1]. Of all retinal detachment surgery cases, 5-10% develop PVR [3].

Corticosteroids have been used as intravitreal injection after retinal detachment surgery as an adjunct to vitrectomy and silicone oil tamponade in treating PVR [4,5]. Despite the potential benefits, intravitreal injection of triamcinolone acetonide is associated with side effects, including glaucoma, cataracts, retinal detachment, and endophthalmitis [6].

Recently, a sustained-release dexamethasone implant (Ozurdex®) proved to be effective for the treatment of macular edema secondary to a variety of underlying diseases with a potentially lower rate of adverse events [7,8,9]. We report a case of rhegmatogenous retinal detachment with a high risk of PVR treated with episcleral surgery and an intravitreal dexamethasone 0.7-mg implant (Ozurdex).

A 35-year-old Caucasian man presented with a macula-off rhegmatogenous subtotal retinal detachment extending 3 quadrants, sparing the inferior nasal quadrant, that had persisted for 1 month in his myopic left eye (fig. 1a). He had no history of previous vitreoretinal surgery, and his best corrected visual acuity was hand motion. Fifteen days before the beginning of the symptoms, he had had an ocular blunt trauma and presented with a large tear in the superior temporal quadrant extending 2 clock hours (fig. 1b), and wrinkling of the edges of the retinal tear and the inner retinal surface, denoting a grade B PVR. His medical history was unremarkable. On examination, the anterior segment was unremarkable and the intraocular pressure was normal. He underwent scleral buckling surgery with circumferential silicone sponge and an encircling silicone band, and subretinal fluid drainage was employed. Cryotherapy was performed to achieve retinopexy (fig. 2a). At the end of the surgery, he received a single intravitreal injection, via pars plana, of dexamethasone 0.7 mg (Ozurdex) as off-label treatment (fig. 2b).

His condition has been stable for at least 9 months now, as seen on the last examination, with his best corrected visual acuity having improved to 0.2 and no sign of PVR or pucker having developed in the treated eye. No complications have been observed, including raised intraocular pressure.

Although PVR is the most common cause of failed repair of rhegmatogenous retinal detachment, risk factors for PVR are related to several well-known pre-, intra-, and postoperative clinical situations. Girard et al. [10] identified a number of significant predictive variables: minor intra- or postoperative hemorrhage, grade A preoperative PVR, preoperative choroidal detachment, giant tears, air tamponade, detachment involving more than 2 quadrants, cumulative break area larger than 3 optic disks, postoperative choroidal detachment, signs of uveitis at initial examination, and grade B preoperative PVR. Young age, intraocular hemorrhage before or after surgery, use of air or sulfur hexafluoride (SF₆), excessive cryotherapy, diathermy or photocoagulation, repeated surgical procedures, loss of vitreous during drainage of subretinal fluid, and the use of vitrectomy are also risk factors that increase the incidence of PVR [11].

Various pharmacological agents have shown potential benefit in reducing postoperative PVR risk, including intravitreal low-molecular-weight heparin and 5-fluorouracil [12]. Clinical reports have suggested that either systemic [13] or intravitreal [14] corticosteroids may be useful in the prevention of PVR. This was mainly attributed to their attenuating effect on the blood-retinal barrier breakdown and their inhibiting effect on the proliferation of RPE cells and fibroblasts, which are thought to be transformed RPE cells, and on myofibroblasts responsible for the contractile properties of PVR membranes. Bali et al. [15] demonstrated that adequate intraocular concentrations of dexamethasone at the time of surgery might reduce the blood-retinal barrier breakdown induced by the surgical trauma during cryotherapy, drainage of subretinal fluid, or intravitreal gas injection, and thereby decrease the incidence of PVR.

Our patient presented several risk factors that could have led to the development of PVR after retinal detachment surgery, including young age, myopia, preoperative grade B PVR, long persistence of the retinal detachment, detachment involving more than 2 quadrants and large tear. We therefore decided to inject an intravitreal dexamethasone 0.7-mg implant (Ozurdex) after the surgery to prevent this complication. At least 9 months after surgery, no sign of PVR or pucker had developed in the treated eye.

To our knowledge, this is the first case described so far in the literature of an intravitreal dexamethasone implant inserted after episcleral surgery for rhegmatogenous retinal detachment to prevent possible PVR. This is just a case report and it has several weaknesses, including the short-term follow-up. Further investigations are needed to demonstrate the role of the intravitreal dexamethasone 0.7-mg implant (Ozurdex) in preventing PVR after episcleral surgery and to understand the long-term treatment outcomes. Intravitreal dexamethasone 0.7-mg implant (Ozurdex) could be considered as off-label treatment after this kind of surgery.

The authors have no conflicts of interest to declare.