Masafumi Uchino

Ruptured aneurysm at a duplicated middle cerebral artery with accessory middle cerebral artery

Summary.Although many cerebral vascular anomalies are widely recognized, others are less well known or unclassified. Accessory middle cerebral artery (MCA) and duplicated MCA are among uncommon anomalies. We present a very rare case of subarachnoid haemorrhage due to rupture of a saccular aneurysm arising from a duplicated middle cerebral artery which was associated with an accessory middle cerebral artery.

Brainstem Involvement in Hypertensive Encephalopathy: A Report of Two Cases and Literature Review

The cerebral hemispheres show prominent involvement in hypertensive encephalopathy far more frequently than the brainstem. Two patients with severe paroxysmally accelerated hypertension associated with brainstem hyperintensity in T2-weighted magnetic resonance images are presented. Both present hyperintense lesions improved dramatically in appearance after stabilization of blood pressure. Extreme acceleration of hypertension may be essential for breakdown of autoregulation in the brainstem circulation. The marked clinicoradiologic dissociation ruled out major brainstem infarction and made tumor unlikely.

Fusiform aneurysm of the vertebral artery presenting with hemifacial spasm treated by microvascular decompression

SummaryWe report a rare case of symptomatic hemifacial spasm caused by a fusiform vertebral artery aneurysm. A 59-year-old woman presented with left hemifacial spasm of 18 months duration. Magnetic resonance imaging showed an enlarged a fusiform aneurysm of the left vertebral artery which compressed the seventh cranial nerve at its exit from the caudal pons. Microvascular decompression of the facial nerve with moving of the aneurysm resulted in complete relief of the hemifacial spasm. No enlargement of the aneurysm was shown on follow-up for a period of 6 years.

Primary midbrain cystic germinoma mimicking glioma: a case with neuroendoscopic biopsy

SummaryIntracranial germinoma arising primarily in the midbrain is extremely rare. We present the first reported case of cystic midbrain germinoma that lacked evident solid components and mimicked a midbrain glioma. In a 22-year-old man with headache and diplopia, magnetic resonance imaging showed a ring-enhancing lesion in the midbrain. The preoperative diagnosis included brain stem glioma, metastasis, and neuroepithelial cyst. A neuroendoscopic biopsy specimen provided a histologic diagnosis of germinoma. The patient responded well to chemotherapy and radiotherapy. The case illustrates the diagnostic value of neuroendoscopic biopsy in the differential diagnosis of brainstem lesions in adult. The possibilities considered should now include germinoma.