The role of short latency somatosensory evoked responses in infants with rapidly progressive ventricular dilatation.

The effect of hydrocephalus on somatosensory evoked potentials was studied in nine infants. An increase in N1 latency was found in five infants studied longitudinally during a period of progressive ventricular dilatation. A marked decrease in N1 latency was noted in 7 infants, within one week following shunt insertion and in two infants who showed spontaneous arrest of ventricular growth. A correlation was found between cerebrospinal fluid pressure and the delay in N1 latency, but the number of infants studied is still small. SEPs appear to be a useful additional test when assessing infants with progressive ventricular dilatation. Once a baseline value for N1 has been obtained following shunt insertion, SEPs may subsequently be useful when assessing a child with possible shunt dysfunction.