Kazuya Uemura

Perfusion-weighted MRI of spinal dural arteriovenous fistula

A 72-year-old woman was admitted with rapidly progressive paraplegia and sphincter disturbance. T2-weighted images of the thoracic spine showed intramedullary high signal with flow voids suggesting dilated medullary veins. Conventional spinal angiography demonstrated a dural arteriovenous fistula draining into perimedullary veins. Perfusion-weighted MRI demonstrated a prolonged mean transit time and increased blood volume in the high-signal area. The loss of normal perfusion gradient and venous hypertension and were thought to produce these differences. The time-to-peak was almost identical in the high-signal and isointense areas, although the bolus of contrast medium arrived earlier in the former. Arteriovenous shunting was thought to cause faster inflow. These changes may have resulted in increased blood volume in the spinal cord. The high signal has been attributed to oedema due to venous congestion, but there has been no histological confirmation. Perfusion MRI in this case supports this hypothesis.

Intradiploic haemangioma associated with epidural haematoma

A 72-year-old female with intradiploic haemangioma associated with epidural haematoma is reported. MRI finding of the lesion is described. The cause of the epidural haematoma is speculated due to fragile vessels attached directly to dura mater through the pores of the inner table of the diploë.

Pneumocephalus associated with fracture of thoracic spine: case report.

A 53-year-old man presented with pneumocephalus following a thoracic vertebral fracture. Computed tomography (CT) myelography revealed a leakage of contrast medium from the thecal sac in the vicinity of the vertebral fracture and was used to confirm the origin of a subarachnoid-pleural fistula.

Bleb formation in small unruptured intracranial aneurysm as a predictor of early rupture

Abstract Small unruptured aneurysms are thought to have a low risk of rupture, but the management of such lesions is still controversial. A 73-year-old man with a small anterior communication artery aneurysm, 4 mm in diameter, while on follow-up, developed an aneurysmal subarachnoid hemorrhage 2 weeks after the detection of a newly emerged bleb on the surface of the aneurysm. In conclusion, the formation of a bleb should be considered as a warning sign of an impending rupture, and treatment should be provided even for patients with small aneurysms.

Exacerbation of major artery aneurysms after revascularization in patients with moyamoya disease: two case reports.

The natural history of aneurysms of the major arteries after revascularization in moyamoya disease has yet to be documented. At our institute, we treated two patients with moyamoya disease-associated aneurysms involving major arteries of the posterior cerebral circulation. The aneurysms became enlarged at an early stage after revascularization, necessitating coil embolization. Although cerebral blood flow was improved in the anterior circulation, revascularization for these patients did not decrease hemodynamic stress in the posterior circulation and was not able to attenuate aneurysmal growth. Therefore, patients with moyamoya disease-associated aneurysms of the major arteries should be carefully monitored after revascularization.