Fig. 1From: Non-visualisation of cavum septi pellucidi: implication in prenatal diagnosis?Normal anatomy of CSP in utero. a, b Occipito-bregmatic and coronal transvaginal ultrasound scans at 21 weeks’ gestation demonstrate normal appearance of CSP (arrow) and CC (dotted arrow). CSP should be seen by 18–20 weeks’ gestation. c, d Axial and coronal T2-weighted MRI at 33 weeks’ gestation demonstrate normal appearance of CSP (arrow) and CC (dotted arrow)Back to article page