gms | German Medical Science

Objective: Spinal dural arteriovenous fistula (SDAVF) is often misdiagnosed due to a long history of varying clinical symptoms mimicking spinal stenosis. Although the underlying pathology of a single vessel malformation is well understood, diagnosis and therapy requires endovascular and neurosurgical capacities.

Method: Since 1986 183 patients were treated by both means in our institution. Clinical symptoms, preoperative myelography, MRI and angiography were analyzed to define the characteristic features of SDAVF. Treatment strategies were reviewed to learn about pitfalls and failure of concepts.

Results: Demographic data of the patient group showed male predominance (m/f ratio of 8/2) with an average of 59 years. Medium time between initial symptom and correct diagnosis were 16 months. 14% showed an acute onset due to subarachnoid or intraparenchymatous hemorrhage. Paresis, sensory loss, bowel and gait disturbances occurred in over 80% of patients. Back pain was less frequent (50%) and not specific. Thoracic location (69%) of the fistula was followed by lumbar (21%) site. Angiography was most sensitive in diagnosing dilated perimedullary veins (100%). Detection of congestive edema was most sensitive in MRI (100%). Cord swelling was less frequently seen on MRI (72%). Endovascular occlusion was performed in half of the patients, surgical transsection was done in 34% of patients. In 16% embolization was incomplete and followed by surgical resection. Clinical symptoms improved in 55%, no change was seen in 37% and deterioration in 8%.

Conclusions: Severe neurological symptoms including bowel and gait disturbances are rarely improved by therapy and an early diagnosis predeterminates the clinical course. SDAVF therapy should follow a clear strategy beginning with an endovascular approach. If the fistula is not accessible by endovascular means or obliteration fails surgical resection is mandatory. In this situation coil-marking of the fistula is very helpful to minimize the surgical approach. Intraoperative ICG and microdoppler are additional tools for successful SDAVF surgery. Postoperative MRI is done routineously today and angiography reserved for suspicious cases in which clinical symptoms and/or medullary edema are not improving.