DOI: https://doi.org/10.36347/sasjm.2025.v11i07.001

Pages: 670-672

Introduction: Dandy-Walker malformation (DWM), characterized by vermian hypoplasia, cystic dilatation of the fourth ventricle, and elevated tentorium cere- belli, is a rare cerebellar anomaly often associated with chromosomal disorders like trisomy 13. Antenatal ultrasound is critical for diagnosis. Case Presentation: A 20-week pregnant primigravida’s fetus was diagnosed with trisomy 13 and DWM via trophoblast biopsy, presenting vermian agenesis, enlarged fourth ventricle, floating tentorium, and increased brainstem-tentorium angle on ultrasound. Results: Multidisciplinary evaluation confirmed the diagnosis, guiding counseling for a poor prognostic outcome. Conclusion: This case highlights the role of ultrasound in detecting DWM and trisomy 13, emphasizing the need for genetic testing and comprehensive counseling in complex fetal anomalies.