Cortical visual impairment: etiology, associated findings, and prognosis in a tertiary care setting.

Purpose: To evaluate the etiology, prognosis, and associated neurological and ophthalmologic findings of children with cortical visual impairment (CVI) at a tertiary care referral facility.

Methods: Records from patients visiting the Vanderbilt University Pediatric Ophthalmology Center during 2002 to 2005 were reviewed, and 98 patients were identified with an International Classification of Disease (9th ed.) coding of CVI (377.75). The charts were reviewed to assess presenting symptoms. The clinic and imaging notes were correlated with visual function (graded on a scale of I to VI).

Results: The most common etiologies were perinatal hypoxia (35%), prematurity (29%), hydrocephalus (19%), structural central nervous system abnormalities (11%), and seizures (10%). Many children (69%) had multiple etiologies. Associated ophthalmic abnormalities included esotropia (19%), exotropia (40%), nystagmus (21%), and optic atrophy (42%). Significant refractive error (> +3.00 D or < -2.00 D) was common (20%). Associated neurological findings included seizures (60%), cerebral palsy (37%), periventricular leukomalacia (12%), hemiparesis (21%), and hearing loss (11%). Fifty-three percent of children initially diagnosed with CVI were followed for a period of 0.5 to 10 years. Forty percent of the patients showed no improvement in visual function; 34% had minimal improvement, and 17% had mild improvement. Only 6% of the patients had significant improvement in visual function. Eight patients had fixing and following or better acuity at last follow-up.

Conclusions: The major risk factors for CVI are perinatal hypoxia, premature birth, and hydrocephalus. Most patients have associated serious neurological and ophthalmologic abnormalities. While many patients have some recovery in vision acuity, most never see well. Patients with the most improvement in visual function were those having better initial acuity.