Familial Exudative Vitreoretinopathy, is a genetic disease usually observed in otherwise healthy children, with symptoms similar to those in retrolental fibroplasia. The disease named, “FEVR,” was first described in medical journals by V. G. Criswick, C. L. Schepens “Familial exudative vitreoretinopathy: a report of two cases” in American Journal of Ophthalmology, Chicago, 1969, 68: 578-594. Symptoms include slowly progressive ocular changes with posterior vitreous detachment, traction on the retina in all quadrants, snowflake opacities in the vitreous body, heterotopia of the macula with temporal traction, subretinal and intraretinal exudates occurring at the periphery (see white subtance in picture), and localized retinal detachment. Disease diagnoses usually occurs between the ages of 18 months and 18 years although if a family knows that there are other members of the family affected by FEVR which concludes that the family has genetic mutations a newborn can be checked at birth if facilities are present and possible sight saving techniques can be used. Most FEVR patients frequently are asymptomatic (showing no eye problems); however, vision in advanced cases may be greatly reduced.
Autosomal Dominant (AD) seems to be the most common form of inheritance although since the prevalence of FEVR is unknown we can not be sure. FEVR appears to be rare, although affected people with normal vision may never come to medical attention. One might conclude that it is rare for FEVR to cause eye problems. FEVR cases are known to occur in every nation around the world.
Lately the genetic causes for FEVR are being studied. Mutations in four genes are now known to cause different types of FEVR. They are labeled in their short version as the FZD4, LRP5, TSPAN12 and NDP genes. The NDP causing many of the X-linked FEVR cases. The FZD4, LRP5, TSPAN12 causing the Dominant and Recessive FEVR cases. Scientists believe these genes provide instructions for making proteins that participate in a chemical signaling pathway that affects the way cells and tissues develop. In particular, the proteins produced from the FZD4 and LRP5 genes appear to play critical roles in the specialization of retinal cells and the establishment of a blood supply to the retina and in NDP gene can possibility cause problems the blood supply of inner ear. The LRP5 protein also helps regulate bone formation in some rare cases. Genetic study continues around the world.
Treatment for FEVR may involve laser photocoagulation or cryoretinopexy for thermal necrosis of the abnormal blood vessels. In cases of retinal detachment, scleral buckle and vitrectomy procedures are commonly employed. Other treatments are also used and many inventions of monitoring (scanning and mapping) the retina are ongoing which help doctors with determining best treatment options.
Some genetic resource web links, which are designed for healthcare professionals and researchers are below. Abstract summaries are usually freely available for all to do their own research. Lately, if you do not have access to the medical database, the first author on the paper has a link to their E-mail. If you would like to read the paper they usually can send you it via. E-mail. Most of the time they have a PDF version to send you.
A list of some of the classic, more older, paper abstracts can be found under the below links. Other general medical
research tools on the web are listed
Helpful links about recessive, dominant and X-linked inheritance
Autosomal Recessive Inheritance