A single center experience of adjusting valve pressure ventriculoperitoneal shunts for the treatment of hydrocephalus in infants under 6 months old.

Introduction: Ventriculoperitoneal shunt (VPS) with adjustable differential pressure valves are commonly used to treat infants with hydrocephalus avoiding shunt related under- or overdrainage. The aim of this study was to analyse the influence of VPS adjustable differential pressure valve on the head circumference (HC) and ventricular size (VS) stabilization in infants with post intraventricular haemorrhage, acquired and congenital hydrocephali.

Methods: Forty-three hydrocephalic infants under 6 months old were prospectively included between 2014 and 2018. All patients were treated using a VPS with adjustable differential pressure valve. HC and transfontanelle ultrasonographic VS measurements were regularly performed and pressure valve modifications were done aiming HC and VS percentiles between the 25th and 75th. The patients were divided into two groups: infants with hydrocephalus due to an intraventricular haemorrhage (IVH-H), and infants with hydrocephalus due to other aetiologies (OAE-H).

Results: The mean of pressure valve modification was 3.7 per patient in the IVH-H group, versus 2.95 in the OAE-H group. The median of last pressure valve value was higher at 8.5 cm H2O in the IVH-H group comparing to 5 cm H2O in the OAE-H group (p = 0.013).

Conclusion: Optimal VPS pressure valve values could be extremely difficult to settle in order to gain normalisation of the HC and VS in infants. However, after long term follow up (mean of 18 months) and several pressure valve modifications, this normalisation is possible and shows that infants with IVH-H need a higher pressure valve value comparing to infants with OAE-H.