Optic neuritis in children--clinical and electrophysiological follow-up.

Optic neuritis (ON) in children usually presents with visual loss, relative afferent pupillary defect (RAPD), abnormal optic disc appearance, defects of visual field and colour vision, as well as with abnormalities of visual evoked potentials (VEP). Both, clinical and VEP parameters, improve after the attack; the time until recovery, however, is as yet unknown. The aim of this study was to follow-up children with ON for 1 year and to determine clinical and VEP recovery. Twelve children (six with bilateral, six with unilateral ON) were studied in the acute phase and systematically followed-up for 1 year. The results show that initially, visual acuity was diminished in all eyes, while after 1 year, in only 14% of them. Optic disc appearance was abnormal in 83.3% of the eyes in the acute phase, and in 85% after 1 year. At the disease onset RAPD could be detected in 67%, visual field defects in 58.5%, and colour vision defects in 50% of eyes, but none of these abnormalities persisted in any eye until the end of study. VEP were abnormal in 83% of eyes in the acute phase and in 56% at the final follow-up (at 6 or 12 months). VEP normalization, when occurred, was mostly observed during the first 6 months. Complete clinical and VEP recovery was observed in three children. Both, clinical and electrophysiological recovery in children with ON were relatively substantial and fast within the first year. VEP improvement may indicate better prognosis.

Pattern ERG and VEP maturation in schoolchildren.

OBJECTIVE: The maturation of the visual system has been studied with pattern electroretinograms (PERG) and pattern visual evoked potentials (PVEP) mostly in children under the age of 6 years. To address the question of maturation of the visual system in childhood and adolescence we investigated age-dependent PERG and PVEP changes in children aged 7-18 years. METHODS: PERG were recorded with skin electrodes attached to the lower eyelid, and PVEP were recorded with 5 electrodes. Visual stimuli, consisting of pattern-reversal 50' checks to full-field and to half-field stimulation, were applied to obtain macular (N70, P100, N145) and paramacular waves (P80, N105, N135). RESULTS: We found an age-dependent decrease (linear regression P<0.05) of PERG P50 amplitude and full-field PVEP P100 latency to monocular right and left eye stimulation, indicating central retinal and postretinal changes. In addition, waveform changes were found in responses to half-field stimulation. The paramacular wave N105 was typically enhanced in younger schoolchildren and diminished with age. The age-dependent decrease (linear regression P<0.01) of paramacular N105 amplitude indicated the increasing predominance of the macular structures of the visual system. CONCLUSIONS: Our findings suggest that central retinal and postretinal electrophysiological maturation persists throughout childhood. Age-dependent PVEP changes seem to correlate with the morphological and metabolic findings that maturation of the visual cortex continues until puberty and even later.