Proliferative Vitreoretinopathy
Proliferative vitreoretinopathy is a disease process comprising of intraretinal fibrosis occurring as a complication of rhegmatogenous retinal detachment (RRD). It starts with expansion of ectopic cells in peri retinal area and vitreous to generate contractile membranes which consequently cause traction on retina and pull it open.
How does PVR develop?
Unlike other wound healing processes, PVR is an atypical wound-healing response essentially driven by inflammatory, retinal, and Retinal pigmentary epithelium cells. PVR begins most frequently with the failure of rhegmatogenous retinal detachment repair. RRD is followed by a breech in the continuity of retina due to trauma or tissue injury in it. This leads to migration and proliferation of inflammatory cells at the site of injury.
The migratory proliferative cells give rise to the formation of contractile membranes in the peri retinal area and vitreous. These cellular contractile membranes exert a contractile pull-on retina resulting in tractional detachment of retina with fixed folds in retina. This detachment of retina and retinal folds are clinically visible during examination of eye. Risks associated with PVR are large tears in retina or untreated already existing retinal detachment, tumors, severe inflammatory reactions and complications from diabetes.
What Are Symptoms of PVR?
Clinically manifestations of PVR observed by patients are listed as follows:
● Prolonged vision loss in patient
● Floaters and flashing lights in the affected eye
● Chronic rhegmatogenous retinal detachment persisting over the span of months
● Aggressive retinitis and choroidal detachment
● Failed RRD surgery, or manipulation in eyes due to multiple retinal surgeries
● Aphakia and choroidal detachment
● Vitreous hemorrhage and high vitreous protein levels
● Positive smoking history
● Preoperative retinal folds
● Horseshoe retinal tears and giant retinal tear
● Uveitis and high degree myopia
● Positive family history and post-surgery for cataracts
● Intraocular inflammation and intra-/postoperative hemorrhage
● Vitrectomy, retinectomy and cryopexy
How to Diagnose PVR
These are the clues of the disease observed by an ophthalmologist during an eye exam:
●Fixed folds in the retina on ophthalmic examination
●Retinal breaks and fiffuse vitreous haze
●Pigment clumps or clusters on the retina
●Wrinkling or folds of inner retina
●Retinal stiffness associated with diminished mobility of the vitreous
●Full thickness, fixed folds which may be located posterior to the equator or anteriorly to it
●Condensed strands of vitreous
Treatment Options for PVR
Treatment options for PVR are chiefly surgical. Occasionally, multiple procedures might be required to deal with PVR accurately. PVR is primarily treated with pars plana vitrectomy and membrane peeling. Other cases of mild PVR have to be managed with a scleral buckle (to seal the retinal breaks).A scleral buckle may or may not be couple with vitrectomy. Retinopexy is used to stabilize reattached retinal breaks.
