Duplicated spinal dural AVFの1例

―術中micro-vascular Doppler検査の有用性―

抄録

A rare case of duplicated spinal dural arteriovenous fistulae is reported. A 31-year-old woman suffering from congestive myelopathy was admitted. Spinal angiography demonstrated dural arteriovenous fistulae at the T10/11 intervertebral foramen. Surgical interruption of the fistulae was performed using micro-Doppler monitoring. Intraoperative micro-Doppler monitoring was performed on the dorsal redundant perimedullary vein, which showed an arterial spectrum. After ligation of the retrogradely irrigating radiculomedullary vein along the right T10 dorsal root, the arterial spectrum diminished, but was restored with time. Repeated temporary clipping under micro-Doppler monitoring disclosed a second dural arteriovenous fistula fed by the anterior spinal canal artery. The arterialized vein proximal to the coronal plexus was coagulated. After this procedure, the arterial spectrum disappeared on the dorsal perimedullary vein. Postoperatively, the patient's neurological deficits improved gradually.
In this case, a second arteriovenous fistula located ventrally was found in addition to the usual radiculomeningeal arteriovenous fistula around the dorsal root. Intraoperative micro-Doppler monitoring was effective for detecting the residual arteriovenous shunting through the second arteriodural venous fistula.
Microdoppler monitoring is an easily available and noninvasive monitoring technique. Use of this monitoring method will yield excellent results in surgery for spinal dural arteriovenous fistulae, and it is especially useful in rare cases such as duplicated arteriovenous fistulae.