In utero diagnosis and treatment of non-human primate fetal skeletal anomalies. I. Hydrocephalus.

We describe the antenatal diagnosis and intrauterine treatment of hydrocephalus induced (corticosteroid teratism) in fetal rhesus monkeys. Diagnostic techniques included (1) maternal serum alpha-fetoprotein (AFP) measurement, (2) ultrasonography of the fetal ventricular system, (3) roentgenography, and (4) fetoscopy. After measuring excessive intracranial CSF pressures in hydrocephalic fetuses, an indwelling prosthetic valve was devised--the hydrocephalic antenatal vent for intrauterine treatment (HAVIT). The HAVIT was surgically implanted in the fetal skull so that when CSF pressures exceeded 60 mm H2O, the ports opened to vent CSF from the fetal ventricular system into the amniotic fluid. Whereas unaided hydrocephalic neonates seldom survived more than ten to 14 days, manifesting progressive muscular weakness and frequent seizures, fetal monkeys receiving the HAVIT demonstrated markedly superior postnatal development of motor skills and weight gain. Although additional laboratory studies are indicated, ultimately, clinical investigations combining early diagnosis and in utero insertion of the HAVIT or similar prosthesis may significantly enhance the prognosis of children in whom severe antenatal hydrocephalus develops.