FETAL AQUEDUCTAL STENOSIS DIAGNOSED SONOGRAPHICALLY - HOW GRAVE IS THE PROGNOSIS

OBJECTIVE. Aqueductal stenosis is a common cause of fetal hydrocephalu s. Published studies of neonates with aqueductal stenosis have noted v ariable outcomes, with normal development seen in 24-86% of cases, In an attempt to better assess long-term outcomes in cases diagnosed in u tero and to determine what prenatal sonographic findings might be used to predict prognosis, a retrospective analysis of patients with aqued uctal stenosis was done. MATERIALS AND METHODS. Fifty-three consecutiv e cases of aqueductal stenosis discovered in utero at two high-risk ob stetrical centers in Seattle between 1980 and 1993 were studied, Paren ts elected to continue pregnancy in 39 of these cases. Two months to 1 0 years of long-term follow-up was available in 30 patients, who form our study group, Prenatal sonograms, postnatal cranial ultrasound, and head CT and MR were evaluated, Prenatal sonographic data collected in cluded the biparietal diameter, size of the lateral and third ventricl es, the ratio of the two, and thickness of the frontoparietal cortical mantle, Medical records provided an assessment of development based o n physical examination, meeting of major milestones, and neuropsycholo gical testing. The in utero diagnosis of aqueductal stenosis was confi rmed by postnatal CT, NIR imaging, sonography, or autopsy. RESULTS. Wi thin the study group of 30 patients, eight died in the postnatal perio d and four died subsequently. Of the 22 patients with adequate postnat al follow-up, moderate or severe developmental delay was present in 16 (73%), Normal developmental milestones were met in only three (10%) o f all 30 patients and in 14% of those surviving the neonatal period. A lthough size of the lateral and third ventricles was not a useful pred ictor of Gong-term prognosis, the ratio of the two, as well as thickne ss of the frontoparietal cortical mantle, was weakly associated with l ong-term prognosis, No correlation was found between biparietal diamet er and outcome. CONCLUSION. As compared with previous reports, prenata l diagnosis of aqueductal stenosis carries a grave prognosis. Twelve o f the 30 patients died, for an overall mortality of 40%. Normal develo pment was seen in only 10%, significantly less than in prior studies.