Time-Resolved Magnetic Resonance Angiography for Follow-Up of Treated Dural and Epidural Spinal Arteriovenous Fistula

Background Spinal arteriovenous fistulas (AVFs) are uncommon vascular malformations of spinal dural and epidural vessels. Actually digital subtraction angiography (DSA) is the gold standard for diagnosis and follow-up. The aim of this study is to demonstrate the validity of the multiphasic magnetic resonance angiography (MRA) to identify recurrent/residual AVFs or their correct surgical and/or endovascular closure. Methods A retrospective cases series with perimedullary venous plexus congestion due to spinal dural or epidural AVF was performed at our center from April 2014 to September 2019. After 1 month from treatment, the patients were subjected to time-resolved MRA and DSA to demonstrate recurrence or correct closure of AVFs. Results We collected a series of 26 matched time-resolved MRA and DSA in 20 patients who underwent an endovascular and/or surgical procedure. In our series, we reported five cases of recurrence. Time-resolved MRA detected six cases of recurrence, with 100% sensitivity and 95% specificity (p < 0.001). We used DSA as the standard reference. Conclusion Time-resolved MRA is a valid tool in posttreatment follow-up to detect recurrent or residual AVFs. It has high sensitivity and specificity and may replace DSA.

Spinal arteriovenous fistula in the lipoma of the filum terminale: A report of two cases and literature review

Background: Filum terminale arteriovenous fistulas (FTAVFs) are rare and their pathogenesis remains unknown. The authors report two cases of FTAVF that arose in the lipoma of the filum terminale. Case Description: The two patients were 72 and 76 years of age, and both presented with a progressive paraparesis. The first patient had an arteriovenous fistula (AVF) located at L5 that was supplied by the anterior spinal artery originating from the left T10 intercostal artery. The second patient’s AVF at L3-4 was fed by the anterior spinal artery originating from the left T8 intercostal artery. Both patients underwent partial resection of the filum terminale at the location of the shunts. The pathological examinations revealed that both the AVFs were embedded in the adipose tissue of the filum terminale, revealing the fatty fila that were not visible in preoperative magnetic resonance images. Conclusion: Two cases of FTAVF were successfully treated by obliterating the fistulas through partial resection of the affected fatty filum terminale. The literature review revealed 13 cases of FTAVF concomitant with the lipomas of the filum terminale. Resection and histological evaluation of the filum terminale should be performed to treat and elucidate the pathogenesis of FTAVF.

Spinal arteriovenous fistula located in the filum terminale externa: A case report and review of the literature

A filum terminale arteriovenous fistula (FTAVF) is an extremely rare spinal arteriovenous fistula (AVF) and typically presents with myelopathy and conus medullaris syndrome caused by venous congestion in the spinal cord. Most reported FTAVFs are intradural pial AVFs with perimedullary drainage in the filum terminale interna. However, there are no reports of AVFs in the filum terminale externa (FTE). We describe a case involving a 68-year-old man with an AVF in the FTE who presented with progressive myelopathy and underwent successful endovascular treatment. We identified the specific shunt point by fusing postoperative computed tomography and magnetic resonance images. The features of the extradural sac AVF developed in the FTE may mimic those of a dural AVF with dural supply to the FTE covered by the dural component, unlike typical FTAVFs where the shunt develops at the pia mater. This case makes a significant contribution to the field by increasing the understanding of the clinical characteristics of an AVF that develops in the FTE and its angioarchitecture.

Spinal Arteriovenous Fistula, A Manifestation of Hereditary Hemorrhagic Telangiectasia: A Case Report

Introduction: Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disorder characterized by arteriovenous malformations (AVM). HHT can have neurological manifestations. Case Report: A 32-year-old woman with a history of HHT presented to the emergency department with acute partial paralysis of the right leg, urinary retention, and right-sided back and hip pain. Magnetic resonance imaging of the spine demonstrated multiple, dilated blood vessels along the cervical spine, diffuse AVMs in the lumbar and thoracic spine, and a new arteriovenous fistula at the twelfth thoracic (T12) vertebral level. Her symptoms improved after endovascular embolization of the fistula. Conclusion: Spinal AVMs are thought to be more prevalent in patients with HHT. Given the high morbidity of arteriovenous fistulas, early recognition and intervention are critical.