B. Schmitt et al., SOMATOSENSORY-EVOKED POTENTIALS WITH HIGH CORTICAL AMPLITUDES - CLINICAL-DATA IN 31 CHILDREN, Neuropediatrics, 25(2), 1994, pp. 78-84
Between 1989 and 1993, somatosensory evoked potentials (SEP) were reco
rded as part of the diagnostic work-up in 282 children with different
neurologic disorders. In thirty-one children the N20/P25/N35 amplitude
s were enhanced compared to our control group (highest amplitude 14.1
muV). Four children had amplitudes > 40 muV (''giant''), fifteen betwe
en 20-39.9 muV (''elevated'') and twelve between 14-19.9 muV (borderli
ne''). Enhanced cortical SEPs were seen in all patients with neuronal
ceroid lipofuscinosis (5 late-infantile NCL > 20 muV, 1 juvenile NCL 1
4.7 muV). In addition, five of six NCL children showed bilaterally pro
longed cervico-cortical conduction times, otherwise only seen in a 4-m
onth-old child following hypoxia. ''Borderline'' and ''elevated'' SEPs
occurred in patients with heterogeneous neurologic disorders. Follow-
up recordings showed inconsistent results: seven children had amplitud
es > 14 muV in all recordings, six only at the first examination, and
six only at follow-up. In six children with hemiparesis enhanced SEPs
were recorded over both (n = 2) or only over the unaffected hemisphere
(n = 4). Myoclonic seizures were observed only m five children with N
CL. Similar to other SEP parameters, enhanced amplitudes are an unspec
ific indicator of an ongoing neurologic disorder. However, in neuronal
ceroid lipofuscinosis, enhanced SEP amplitudes may be a useful diagno
stic criterium.