To determine
vigabatrin's effectiveness and the prevalence of symptomatic
visual impairment (i.e., impairment affecting the ability to perform everyday activities) associated with its
therapy in pediatric
epilepsy, we retrospectively reviewed medical records of 156 patients receiving
vigabatrin at Cincinnati Children's Medical Center from 1998-2010. In addition to demographics and
vigabatrin dosing information, data included seizure type/frequency at presentation and subsequent follow-up. Of 156 patients, we excluded 35 because their medical records were insufficient to permit verification of the exact duration or timing of
vigabatrin treatment. To evaluate efficacy (n = 121/135), we used a 5-point scale (0-4) to compare seizure frequency at several time points. To evaluate
visual impairment (n = 63), we reviewed serial ophthalmologic evaluations at baseline and during treatment for patients in whom they were clinically indicated. Mean age at treatment initiation was 1.8 years (range, 0.1-29.2 years).
Treatment duration ranged from 0.7-101.0 months, with an estimated average daily dose of 79 mg/kg/day.
Tuberous sclerosis complex was the commonest seizure etiology (83%). Partial-onset seizure, alone or with
infantile spasms, was the commonest seizure type (84%). Seizure frequency decreased from 3.7 ± 0.6 S.D. at baseline to 1.8 ± 1.7 S.D. at 6 months (P < 0.001). Responses to
vigabatrin did not differ by
tuberous sclerosis complex or nontuberous
sclerosis complex etiology, and were sustained for 5 years. Sixty-three patients (∼50% of all patients evaluated) underwent clinically indicated ophthalmologic assessments during the review period. In our clinical judgment, no cases of clinically relevant
vigabatrin-associated
visual impairment occurred.
Vigabatrin was effective for refractory childhood partial-onset
epilepsy, and was not associated with symptomatic vision loss.