Sonographic detection of inferior vermian agenesis in Dandy-Walker malformations: prognostic implications.

PURPOSE

To compare the prognoses for fetuses with sonographically detected inferior vermian agenesis (IVA) or complete vermian agenesis (CVA).

MATERIALS AND METHODS

The sonograms of 65 fetuses with Dandy-Walker malformations were retrospectively reviewed. Fetuses were divided into two groups--those with IVA and those with CVA.

RESULTS

Of the 65 fetuses, 37 had IVA; 28, CVA. Thirteen (20%) of the 65-nine (24%) of the 37 with IVA and four (14%) of the 28 with CVA--lived for longer than 1 year. Chromosomal abnormalities were found in 23 (45%) of the 51 fetuses tested for karyotypic abnormalities or clinically thought to have Down syndrome. Seventeen (53%) of the 32 with IVA and six (32%) of the 19 with CVA that were tested for karyotypic abnormalities or clinically thought to have Down syndrome had chromosomal abnormalities (P = .07). Associated morphologic abnormalities were prenatally detected in 49 (75%) of the 65-in 28 (76%) of the 37 with IVA and in 21 (75%) of the 28 with CVA.

CONCLUSION

The overall guarded prognosis is similar for fetuses with Dandy-Walker malformations for whom IVA or CVA has been sonographically diagnosed. Fetuses with IVA have a higher prevalence of karyotypic abnormalities.