Prevention of postshunting ventricular asymmetry by transseptal placement of ventricular catheters. A randomized study.

Ventricular asymmetry is common after ventricular shunting, and occasionally isolation of the contralateral ventricle necessitates a second shunt. The following study was performed to determine whether contralateral placement of the ventricular catheter via ultrasound-guided perforation of the septum pellucidum would decrease the incidence of postshunting ventricular asymmetry which might predispose to symptomatic isolation of a lateral ventricle. Fifty-eight children with hydrocephalus and an open fontanel, who were having a ventriculo-peritoneal shunt via a parieto-occipital approach, were randomized to have the ventricular catheter tip placed into either the ipsilateral or the contralateral frontal horn. Ventricular asymmetry occurred in 23% of the patients with contralateral versus 54% with ipsilateral placement (chi 2 = 5.53; p = 0.019). In 7 patients with contralateral placement, in whom a special catheter with two sets of holes was used, such that holes were located in both ventricles, no shunt-related ventricular asymmetry occurred. In 2 children with ipsilateral placement, a second shunt was required for a symptomatic isolated lateral ventricle. Perforation of the septum pellucidum with placement of the ventricular catheter in the contralateral ventricle, using a specially designed catheter with two sets of holes, may decrease the incidence of postshunting ventricular asymmetry and symptomatic isolation of a lateral ventricle.