folds and breaks should be treated before cataract extraction. Prophylactic retinopexy may be appropriate in certain patients.

Snead MP, McNinch AM, Poulson AV, et al. Stickler syndrome, ocular-only variants and a key diagnostic role for the ophthalmologist. Eye (Lond). 2011;25(11):1389–1400.

Norrie disease

Norrie disease is an X-linked recessive disorder of retinal dysplasia caused by a mutation in the NDP gene, which encodes for the protein norrin.

Diagnosis Affected boys are typically born blind and have varying degrees of hearing impairment and intellectual disability. The condition is characterized by a distinctive retinal appearance: a globular, severely dystrophic retina with pigmentary changes in the avascular periphery. During the first few days or weeks of life, a bilateral, yellowish retinal detachment appears, followed by a whiter mass behind the clear lens. Over time, the lenses, and later the cornea, opacify; phthisis bulbi may ensue by age 10 years or earlier. Female carriers show peripheral retinal abnormalities.

Treatment No treatment exists.

Familial exudative vitreoretinopathy

Familial exudative vitreoretinopathy (FEVR) is a disease of abnormal retinal vascularization similar to that seen in ROP (discussed earlier in the chapter). Type 1 FEVR is autosomal dominant and is caused by a mutation on chromosome 11. Type 2 FEVR is an X-linked recessive disorder caused by a mutation in the NDP gene, the same gene involved in Norrie disease.

Diagnosis Posterior pole findings in FEVR include retinal traction, folds, breaks, and detachment secondary to vitreous traction; posterior vitreous detachment; avascular peripheral retina; and thick peripheral intraretinal and subretinal exudates. The disease is bilateral and can mimic ROP but affects infants born at full term. Fluorescein angiography shows areas of retinal nonperfusion. Examination of family members is important in the diagnosis of FEVR. Affected family members can show marked variation in severity, from minimal straightening of retinal vessels and peripheral nonperfusion to total retinal detachment.

Treatment Cryopexy, photocoagulation, retinal detachment surgery, vitrectomy, and cataract surgery have all been used to manage this disorder.

Infections

Herpes Simplex Virus and Cytomegalovirus

Herpes simplex virus and cytomegalovirus are discussed in Chapter 28.

Human Immunodeficiency Virus

The ocular complications of HIV infection have been observed only rarely since the advent of highly active antiretroviral therapy (HAART). Such complications typically occur only in children with advanced HIV infection who are severely immunocompromised. For more information, see BCSC Section 9, Intraocular Inflammation and Uveitis, and Section 12, Retina and Vitreous.