Can prenatal ultrasound findings predict ambulatory status in fetuses withopen spina bifida?

OBJECTIVE: To determine whether prenatal sonographic findings in fetuses wi th open spina bifida can predict ambulatory potential and the need for post natal shunt placement. STUDY DESIGN: Ongoing pregnancies complicated by isolated open spina bifida from January 1996 to March 2000 were studied retrospectively. Static image s and reports generated every 3-4 weeks from diagnosis until delivery were reviewed for lesion level and type, ventricular width, and lower extremity appearance. Operative summaries as well as neonatal and pediatric charts we re reviewed, Ambulatory was defined in infants greater than or equal to2 ye ars old as walking with or without appliances. In those <2 years of age, am bulatory was defined as at least 4/5 lower extremity muscle strength. RESULTS: Thirty-three cases of isolated open spina bifida were identified. Lower (more caudal) lesion levels and smaller ventricular size were associa ted with ambulatory status in univariate analyses (P < .001, P=.003, respec tively). No infant with a thoracic lesion was ambulatory (n=11); all had ve ntriculomegaly diagnosed prenatally and all required shunt placement. In co ntrast, all infants with L4-sacral lesions (n=10) were ambulatory, and 60% had ventriculomegaly diagnosed prenatally. Of patients with L1-L3 lesions ( n=12), 50% were ambulatory. In this group, ambulatory potential could not b e determined by the presence of ventriculomegaly, ventricular size, or the presence of club foot. In the entire cohort, no infant with a myeloschisis was ambulatory, and all infants except one with a sacral lesion required po stnatal shunt placement. CONCLUSIONS: Sonographic determination of lesion level and type is useful i n predicting the ambulatory potential of fetuses with open spina bifida.