Correlation of prenatal ultrasound diagnosis and pathologic findings in fetal brain abnormalities

Objective To determine the degree of agreement between prenatal ultrasound diagnosis of brain abnormalities and subsequent pathologic findings. Methods Between August 1993 and August 1999 there were 62 cases where a fet us with a prenatal ultrasound diagnosis of a brain abnormality other than n eural tube defects underwent autopsy at the Regional Department of Pediatri c Pathology. The cerebral diagnosis at ultrasound was compared with the fin dings at autopsy in all cases. Results In 47 of 61 (77%) cases the same defects were seen on ultrasound an d at autopsy. The most common disparity was with the Dandy-Walker malformat ion or variant, where only six of the 14 (43%) cases Prenatally diagnosed w ith this condition showed the same abnormality at autopsy. When fetuses wit h the Dandy-Walker malformation or variant were excluded, the scan findings correlated with autopsy in 41 of 47 (87%). In the main group with discorda nt findings, five of the seven cases where termination of pregnancy was und ertaken had other fetal anomalies on ultrasound examination which were conf irmed at autopsy. In the sixth case there was autolysis of brain tissue whi ch affected detailed autopsy Conclusions A very high level of agreement between prenatal ultrasound and autopsy findings was found for all abnormalities of the fetal brain, except for the Dandy-Walker malformation or variant. Potential discrepancy in fin dings between ultrasound and autopsy should be explained to patients who ar e considering termination of pregnancy for the Dandy-Walker type of abnorma lity.