Characterized by microphthalmia with bilateral
degeneration of the retina and vitreous humor leading to early blindness,
usually within the first weeks of life. Characteristic ocular findings
include retinal detachment, vitreous hemorrhage, and formation of
retrolental masses. Pupils are dilated with no light reflex. Cataracts.
Phthisis bulbi (shrinkage of the eyeball) develops over the first decade of
life. In approximately one third of Norrie disease patients, progressive
sensorineural hearing loss occurs, with age at onset varying from a few
months of life to adulthood. Some degree of mental retardation is frequent
(up to 50% of patients), although many individuals have normal
intellectual capabilities. Several individuals with complex syndromic anomalies have
been described in whom Norrie disease was part of the clinical findings.
Associated anomalies in these cases included hypogonadism, increased
susceptibility to infections, skeletal malformations, and a combination of
facial features, including hypotelorism, narrow nasal bridge, thin upper
lip, and large ears.