Pattern reversal visual evoked potentials following early treatment of unilateral, congenital cataract.
OBJECTIVE
To describe the pattern reversal visual evoked potentials (VEPs) that were used to monitor and quantify early visual development following treatment for dense, unilateral, congenital cataract.


METHODS
Longitudinal prospective study.


METHODS
Six infants who underwent surgery and contact lens correction before age 5 months and who had good compliance with occlusion therapy throughout the first 3 years of life.


RESULTS
Initially, VEPs from aphakic eyes showed marked abnormalities, including small amplitudes, prolonged latencies, missing components, and absent VEPs to small check sizes. Threshold check size was elevated by 3 octaves or more. With part-time occlusion of the opposite eye, VEPs normalized rapidly in the first year, but residual deficits remained to age 4 years when visual acuities were between 20/50 and 20/120 in aphakic eyes. Threshold check size clearly differentiated between aphakic and normal eyes and was the only VEP parameter that was correlated with single-letter visual acuity. Thus, threshold check size had greater clinical use than measures of pattern VEPs based on latency, amplitude, or waveform.


CONCLUSIONS
Patients treated for unilateral congenital cataract, who have early surgery and contact lens correction and comply with occlusion therapy, show a period of rapid VEP maturation and have a good visual prognosis.
McCulloch
D L
DL
Department of Ophthalmology, Hospital for Sick Children, Toronto, Ontario.
Skarf
B
B
D001036:Aphakia, Postcataract / Q000503:physiopathology / Q000628:therapy; D002386:Cataract / Q000151:congenital* / Q000503:physiopathology; D002387:Cataract Extraction; D003261:Contact Lenses; D005074:Evoked Potentials, Visual / Q000502:physiology*; D006801:Humans; D007223:Infant; D008137:Longitudinal Studies; D010364:Pattern Recognition, Visual; D011379:Prognosis; D011446:Prospective Studies; D012683:Sensory Deprivation; D012684:Sensory Thresholds / Q000502:physiology; D014785:Vision, Ocular / Q000502:physiology*; D014792:Visual Acuity