[Somatosensory evoked potential of the lower extremity in the premature neonate].
The morphology of SEP is a good index of cortical maturation. Cerebral SEP is elicited by stimulation of the posterior tibial nerve at 38 wk post-conceptional age in 37 neonates distributed in 3 groups: I = gestational age (GA) at birth less than 31 wk; II = GA 23-36 wk; III = full-term neonates (FTN). A somatosensory response was identified in only 21 cases (56.8%). The presence of SEP in 3 groups, ie I, II, III, was 45.5%, 53.8% and 69.2% respectively. The morphological characteristics studied (latencies, amplitude and rising time) in these neonates were different: the peak latencies of major positive wave (P1) and rising time were not significantly different between I and III. These parameters were statistically different between II and III. SEP development is linked to some morphological factors-height, and growth-but also to the maturation of the central nervous system (myelinisation and central pathway organization). These results indicate that until 38-39 wk post-conceptional age, the maturation of the central somatosensory pathway is variable at different birth periods; this suggest the possible role of extra-uterine factors of in the acceleration of neurological development.
Tranier
S
S
Service central d'explorations fonctionnelles, hôpital Ambroise-Paré, Boulogne, France.
Chevallier
B
B
Lemaigre
D
D
Liot
F
F
Lagardère
B
B
Gallet
J P
JP
D004558:Electric Stimulation; D004576:Electromyography; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature / Q000502:physiology*; D007866:Leg / Q000294:innervation*; D008297:Male
Potentiel évoqué somesthésique du membre inférieur chez le nouveau-né prématuré.