Presentation
23 weeks pregnant for routine obstetric antenatal check up.
Patient Data




The skull shape is abnormal and reveals bilaterally symmetric indentation over the frontal bone giving it a typical appearance called lemon skull sign. The cerebellum appears smaller than normal for gestational age and it is abnormal in shape (curved/banana shaped), so called banana cerebellum.
The above findings are associated with a thin walled cystic lesion with internal echoes noted posterior to lumbosacral spine, the lesion shows communication with the spinal canal and there Lumbosacral spina bifida signifies myelomeningocele.
Imaging features are suggestive of Chiari II malformation.
Case Discussion
Chiari II malformation is relatively common congenital anomaly with an incidence of 1:1000 live births. It can be associated with wide range of skeletal and CNS anomalies.