Intrauterine shunt for obstructive hydrocephalus--still not ready

To determine the safety and efficacy of ventriculoamniotic shunt placement through a hysterotomy in the second trimester of pregnancy as treatment for isolated obstructive hydrocephalus.

Between 1999 and 2003, four pregnancies with isolated fetal obstructive hydrocephalus in the second trimester were treated at Vanderbilt University Medical Center. Preoperatively, all fetuses underwent serial ultrasonographic examinations and an ultrafast magnetic resonance imaging to confirm isolated aqueductal stenosis. A normal fetal karyotype and negative polymerase chain reaction or culture of the amniotic fluid for cytomegalovirus and toxoplasmosis were obtained. Serial enlargement of the lateral ventricles >1.5 mm/week and fetal macrocephaly were documented. Using epidural and GETA, a standard ultrasmall ventricular catheter and valve were inserted via a hysterotomy. The distal catheter, rather than being inserted into the fetal peritoneum, exited between the fetal scapulae. Patients were discharged home from the hospital, and the remainder of their prenatal care was provided by their local obstetrician. After delivery, the distal drain was converted to a ventriculoperitoneal shunt.

Cases were performed at 23 6/7, 25 5/7, 26 4/7, and 26 5/7 weeks. Shunts performed well during pregnancy, and were intact at delivery. Deliveries occurred at 34 1/7, 27 1/7, 28, and 32 4/7 weeks. Birthweights were 2,010, 907, 1,200, and 2,220 g. All Apgar scores were normal. Case 1 developed a neonatal shunt infection, and is now developmentally delayed, with swallowing dysfunction, hearing deficits and a poor pupillary response. Case 2 developed neonatal sepsis and is now developmentally delayed. Case 3 delivered preterm due to chorioamnionitis, and neonatal death occurred from sepsis. Case 4 is developmentally delayed.

Ventriculoamniotic shunt can be placed through a hysterotomy, overcoming many of the technical difficulties of earlier percutaneous shunts. However, recent developments in fetal imaging and molecular genetics have not improved case selection. Unless new breakthroughs occur, fetal shunting cannot reasonably be expected to improve perinatal outcome.