CASE 836 Published on 22.03.2001

Fetal MRI in holoprosencephaly and mega cisterna magna



Case Type

Clinical Cases




22 years, female

No Area of Interest ; Imaging Technique MR
Clinical History
Fetal MRI
Imaging Findings
A 22-year-old pregnant woman underwent an ultrasound examination for evaluation of her fetus at the 24th week of gestation. Enlarged lateral ventricles, and enlarged posterior fossa were noted. The woman was referred for intrauterine MRI. On MRI, the HASTE (half-Fourier single-shot turbo spin echo), and the TRUFI (True FISP = fast imaging with steady state precession) sequences were used. In each of these fast imaging sequences acquisition time was 11 seconds.
Fetal fast MRI with HASTE or TRUFI sequences provides evaluation of especially the brain in a quite detailed fashion. Fetal MRI could be a complementary method to fetal ultrasound studies with respect to confirming the findings especially in brain malformations. In the current fetus, fusion of the frontal lobes, pathognomonic finding for holoposencephaly, was well demonstrated by intrauterine MRI. Lateral ventricles were dilated, and they appeared as a single ventricle. Presence of relatively well developed hemispheres suggested lobar type of holoposencephaly, compared to more severe types referred to as semilobar, and alobar holoposencephaly. An additional finding was mega cisterna magna. Demonstration of a normal 4th ventricule excluded Dandy-Walker malformation. It is known that in some patients with mega cisterna magna supratentorial anomalies can occur, however, coexistence of a severe anomaly like holoprosencephaly is unusual. The pregnancy was terminated, and the diagnosis of holoprosencephaly was confirmed with an impression favoring lobar form of the anomaly.
Differential Diagnosis List
holoprosencephaly and mega cisterna magna
Final Diagnosis
holoprosencephaly and mega cisterna magna
Case information
DOI: 10.1594/EURORAD/CASE.836
ISSN: 1563-4086