Abnormal cerebral vein morphology
Vein of Galen aneurysmal malformation
MSH:C536535
SNOMEDCT_US:253194008
UMLS:C0431420
Median prosencephalic arteriovenous fistula
The most common vascular CNS anomaly in the fetal brain is the vein of Galen malformation. At prenatal US, an anechoic cystic mass is seen in the midline, superior and posterior to the third ventricle and thalamus. Color and spectral Doppler imaging demonstrate the presence of low-resistance flow and a turbulent waveform. Blood flow may be seen draining posteriorly into the venous sinuses. See Figure 13 of PMID:32706613.
Vein of Galen aneurysmal malformation is a choroidal type of arteriovenous malformation that develops between 6 and 11 weeks of gestation. It results from 1 or more arteriovenous fistulas shunting blood toward the prosencephalic vein of Markowski, the embryonic precursor of the vein of Galen. This abnormal shunt leads to progressive dilation of the vein and prevents its involution and subsequent development into the vein of Galen.
Vein of Galen malformation
Vein of Galen aneurysm