VCAN-Related Vitreoretinopathy

Excerpt

Clinical characteristics: VCAN-related vitreoretinopathy, which includes Wagner syndrome and erosive vitreoretinopathy (ERVR), is characterized by progressive degenerative changes of the vitreous (syneresis) and the vitreoretinal interface. Syneresis can lead to massive liquefaction of the vitreous such that on slit lamp examination the vitreous cavity appears optically empty ("empty vitreous") with pockets of liquefied vitreous that are usually lined by avascular strands and veils. Preretinal vitreous membranes that span the whole equator of the eye are characteristic. Although the first ocular signs usually become apparent during early adolescence, they can be evident as early as age two years. The vitreous degeneration, which is assumed to be the primary pathology, leads to secondary changes including presenile cataract, degeneration and atrophy of the retina and the underlying retinal pigment epithelium and choroid, and retinal detachment. Systemic abnormalities are not observed.

Diagnosis/testing: The diagnosis of VCAN-related vitreoretinopathy is established in a proband with suggestive ocular findings and a heterozygous VCAN pathogenic (or likely pathogenic) variant identified by molecular genetic testing.

Management: Treatment of manifestations: Refractive error is corrected by spectacles or contact lenses. Visually disabling cataract is treated by cataract surgery, preferably by an experienced surgeon. Posterior capsule opacification is treated with YAG laser capsulotomy. Retinal breaks without retinal detachment are treated with laser retinopexy or cryocoagulation. Vitreoretinal surgery is indicated for retinal detachment, vitreoretinal traction involving the macula, or epiretinal membranes involving the macula.

Surveillance: Annual ophthalmologic examination by a vitreoretinal specialist.

Evaluation of relatives at risk: It is appropriate to clarify the genetic status of apparently asymptomatic older and younger at-risk relatives of an affected individual in order to reduce morbidity by early diagnosis and treatment of ophthalmologic complications.

Genetic counseling: VCAN-related vitreoretinopathy is inherited in an autosomal dominant manner. Most individuals diagnosed with VCAN-related vitreoretinopathy have an affected parent. Each child of an individual with VCAN-related vitreoretinopathy has a 50% chance of inheriting the pathogenic variant. Once the VCAN pathogenic variant has been identified in an affected family member, prenatal and preimplantation genetic testing for VCAN-related vitreoretinopathy are possible.