[A case of cerebral venous angioma detected by slow velocity-encoding phase contrast MRA: appropriate determination of velocity encode].

We report a 86-year-old woman who has been diagnosed as cerebral venous angioma by slow velocity-encoding phase contrast magnetic resonance angiography (MRA). She had developed headache for one month. T1- and T2-weighted images showed a flow void sign in the right cerebellum with gadolinium enhancement. MRA using time-of-flight sequence revealed no abnormal vascular structures. Conventional phase contrast MRA (velocity encode, 40 or 60 cm/sec) did not disclose obvious vascular abnormalities. However, slow velocity-encoding (20 cm/sec) phase contrast MRA demonstrated a well-demarcated venous angioma in the right transverse sinus. Our results of MRAs suggest that velocity encode is a crucial factor for detection of venous angioma on phase contrast MRA. Slow velocity-encoding phase contrast MRA is a beneficial tool for evaluation of venous malformations, such as venous angioma.