Treatment and outcome of spinal dural arteriovenous fistulas

Abstract

IntroductionSpinal vascular malformations are rare and often misdiagnosed entities. In principle, we distinguish between three types of spinal vascular malformation: extradural, dural, and intradural [2,6,7,11,12]. The intradural malformations can be separated into perimedullary fistulas and the real intramedullary arteriovenous malformations (AVMs). Intradural AVMs are supplied by spinal-cord supplying arteries, whereas dural malformations are supplied by meningeal arteries as branches of the radicular artery [6,12]. Eighty percent of all spinal AVMs are dural fistulas. In contrast to the probably inborn perimedullary fistulas, dAVFs are most likely acquired [11,12]. The fistula itself is located in the dural layer near the penetration point of the nerve root. Venous drainage runs along the spinal cord veins on the surface of the cord, because the local radicular venous drainage is missing. The high venous pressure is presumed to be the cause of clinical symptoms [2,6,9,11].Abstract Spinal dural arteriovenous fistula (dAVFs) are rare and often misdiagnosed entities. The choice between surgical treatment and embolization remains a matter of debate. We report on the cases of 18 patients (16 men, 2 women) with dAVF, who were treated surgically over an 11-year period. Patient age ranged from 32 to 84 years (mean 60 years). Six patients underwent embolization preoperatively. In three cases, angiography examinations failed to show feeding arteries on first examination at neuroradiological centers. Feeding arteries were at a different level than the fistula point in seven patients, two of them presenting with new anastomoses after embolization. Location of the fistula was midthoracic to lumbar. Seven patients were variously misdiagnosed with tumor, polyneuropathy, Guillain-Barré syndrome, syringomyelia, and knee disease. Clinical history was characterized by slowly progressive and fluctuating deterioration.Initial symptoms were mainly sensory loss and motor weakness, lasting for between 4 and 45 months before diagnosis (mean 15 months). Recurrent fistula after operation was found in one patient. In another patient, control angiography revealed a fistula at another level, and in a third, a fistula on the contralateral side. All three patients underwent reoperation. Temporary clinical deterioration was found in four patients, seven remained unchanged, and seven improved postoperatively. An attempt at embolization should be made following diagnostic angiography. Otherwise, surgery is our recommended treatment for spinal dural fistulas, as it has a lower failure rate. Because of the progressive natural course with severe deficits, we favor an early definitive treatment.

Venous congestive myelopathy: a mimic of neoplasia

“…19 The surgical pathologist may encounter spinal cord biopsies from these patients; thus it is necessary to be familiar with the histologic features of venous congestive myelopathy to avoid a misdiagnosis of neoplasm and to identify a surgically treatable condition. 11,12,[20][21][22][23] Herein, we report the clinical/histopathologic findings and follow-up in a group of seven patients who underwent spinal cord biopsy with a preoperative clinical and radiographic diagnosis of neoplasia. All were found to have histologic findings characteristic of venous congestive myelopathy and suggestive of an associated spinal dural arteriovenous fistula.…”

Indocyanine green videoangiography “in negative”: definition and usefulness in spinal dural arteriovenous fistulae

“…Visualization of a rapid filling of the dilated venous system in apparent continuity with the medullary vein, after CIGV, does not establish unequivocally the affected level, as demonstrated in case 2 presented in the present work. Although some authors [22] have defined that the interpretation of the rapid and retrograde filling of the venous system typical of these injuries are easily identified by the CIGV, according to our experience and literature, where several authors have defined recurrence of the fistula after surgery, difficulties to localize the fistula or appearance of another fistula at different levels [10,20], this is not so simple and may lead to errors as stated in case 2. Therefore, any of the components of the fistula, arterial afference, fistulous point and arterialized vein efference cannot be defined unequivocally by the CIGV.…”

Spinal Dural Arteriovenous Fistulas Supplied from Multiple Segmental Arteries: Microsurgery Using Indocyanine Green Angiography and Radiosurgery with a Spine Tracking System

“…However, surgical difficulties are often encountered in patients with large d-AVFs supplied from multiple segmental feeding arteries or d-AVFs with feeding arteries originating from a different level than the fistula point [3]. The recently developed indocyanine green (ICG) angiography technique is very useful for detecting feeding arteries or draining veins at different levels [9].…”

“…In Group 1, symptoms develop slowly due to compression of the spinal cord and/or nerve roots by enlarged epidural venous pouches [1]. Treatment with endovascular occlusion and/or surgical disconnection of fistulas is required in patients with acute or rapidly progressive symptoms before the spinal cord damage becomes irreversible [2][3][4]. Benign fistulas are a developing indication for radiosurgery [5].…”