Cerebral venous angiomas: MR findings.

Seven patients with suspected cerebral venous angioma studied by either CT or angiography were imaged with magnetic resonance. Six of seven cases demonstrated a stellate appearance on contrast enhanced CT. In two patients this finding was verified by angiography. Flow void was identified on both T1- and T2-weighted pulse sequences. In one patient a field echo sequence demonstrated high intensity signal within the venous angioma. Magnetic resonance proved superior to CT in the identification of these lesions. A stellate configuration with an emanating transcortical vein and centrifugal drainage (transcortical venous flow) from the angioma into a sinus was present in all cases. Centripetal drainage via thalamostriate and internal cerebral veins was not seen. There was no evidence of mass effect, scar, or hemorrhage. Four of the angiomas were located in a frontal lobe and three in a cerebellar hemisphere. This distribution of the lesions is similar to that reported in the literature in which the frontal lobe is the most common location followed by the cerebellar hemisphere. An embryological explanation is cited and supported by a review of the literature.