[A case of spinal dural arteriovenous malformation associated with the broad lesion within spinal cord--diagnostic value of MRI with Gd-DTPA enhancement].

A 70-year-old man, with slowly progressive gait disturbance, numbness in his lower limbs and dysuria, was admitted to our hospital in July, 1988. Neurological examination revealed flaccid paraparesis, hyperesthesia below the level of Th-10 combined with the disturbance of pain and temperature sensations below the level of Th-11, and neurogenic bladder. Midsagittal Tl-weighed image of MRI did not reveal any abnormal finding except for a mild enlargement of the conus medullaris. With Gadolinium (Gd)-DTPA injection, however, the spinal cord was diffusely enhanced below the level of the 9th thoracic spine. This enhancement effect was particularly remarkable at the periphery of the spinal image showing several high intensity spots in the posterior aspect of the spinal cord, which was thought to be incompatible with the spinal cord neoplasm. The angiographic examination of the selective Th-7 intercostal artery on the left showed vascular malformation lying adjacent to the 7th intervertebral foramen with markedly dilated tortuous spinal veins going upwards and downwards, which was compatible with spinal dural arteriovenous malformation (AVM). After the artificial embolization, draining veins as well the nidus of AVM had completely disappeared on angiogram. There was an improvement on his neurological findings and Gd-DTPA enhancement had been diminished on MRI. It was suggested that Gd-DTPA enhancement on MRI was due to the dilated and remarkably congestive spinal veins, and that both the elevated venous pressure and reduction of intramedullary arteriovenous pressure gradient were the cause of the development of clinical symptoms.