Filum Terminale Arteriovenous Fistula Research Articles

Anatomical considerations regarding a high-flow arteriovenous fistula below the conus medullaris in a patient with hereditary hemorrhagic telangiectasia: Case report.

Cauda equina radicular arteriovenous fistulas are rare "low flow" shunting lesions characterized by direct communication between the radicular artery and vein of a cauda equina nerve root. None have been associated with hereditary hemorrhagic telangiectasia and a high-flow cauda equina radicular arteriovenous fistula has never been reported. We present a unique case of a high-flow cauda equina radicular arteriovenous fistula in a patient with hereditary hemorrhagic telangiectasia. Marked flow-induced vascular remodeling posed significant diagnostic and therapeutic challenges which will be highlighted in this report. A 39-year-old female with genetically confirmed hereditary hemorrhagic telangiectasia presented with progressive thoracic myelopathy secondary to a high-flow single-hole arteriovenous fistula below the conus. The feeding artery, arising from the anterior spinal artery, and draining vein had a paramedian course, favoring the diagnosis of a cauda equina radicular arteriovenous fistula (supplied by a proximal radicular artery) over a filum terminale arteriovenous fistula. Transarterial embolization was attempted but significant elongation and tortuosity of the anterior spinal artery precluded microcatheter access to the fistulous point. Surgical disconnection was successfully performed. The intraoperative findings supported the diagnosis of cauda equina radicular arteriovenous fistula. Delayed neurologic deterioration secondary to overshooting venous thrombosis was observed. She recovered after the initiation of therapeutic anticoagulation. To the best of our knowledge, we hereby report the first high-flow cauda equina radicular arteriovenous fistula. The accurate differentiation of cauda equina radicular arteriovenous fistula from filum terminale arteriovenous fistulas, while challenging, is important to avoid treatment-related complications. Careful preoperative planning, the use of specialized endovascular and surgical techniques, and meticulous postoperative care can ensure the safe and complete disconnection of high-flow cauda equina radicular arteriovenous fistulas.

Coexisting filum terminale arteriovenous fistula and filum terminale lipoma treated with single-stage surgery: illustrative case

Both filum terminale arteriovenous fistulas (FTAVFs) and filum terminale lipomas (FTLs) are rare. Because of this rarity, there is a paucity of data regarding concomitant FTAVF and FTL, and the optimal treatment remains to be defined. The authors describe a patient with coexisting FTAVF and FTL treated with single-stage surgery. A man in his 70s was referred to the authors' department because of a suspected spinal vascular malformation seen on magnetic resonance imaging that was performed to investigate lower limb weakness, intermittent claudication, and urinary incontinence. Previous imaging had shown a terminal lipoma with an internal flow void. Computed tomography angiography and digital subtraction angiography revealed an FTAVF, the feeder being a lateral sacral artery. The patient was treated surgically with curative intent. The FTL and tethered cord that had been identified by imaging were treated in the same procedure. Postoperative digital subtraction angiography showed absence of the abnormal vessels. The patient was discharged home on the 19th postoperative day. When considering treatment, it is important to determine whether symptoms are attributable mainly to FTL, tethered cord, or FTAVF. One-stage treatment is useful because it eliminates both the FTAVF and the factors that led to its development.

Filum terminale arteriovenous fistula with additional arterial supply by the posterior spinal artery: A report of two cases

Filum terminale arteriovenous fistulas (FTAVFs) are rare and usually supplied by the artery of the filum terminale, distal termination of the anterior spinal artery (ASA). These fistulas may also supply from the lateral sacral artery (LSA) arising from the internal iliac artery and/or middle sacral artery. Additional supply by the posterior spinal artery (PSA) has never been mentioned before. The authors describe two middle-aged men harboring FTAVFs manifested with progressive myelopathy and bowel/bladder dysfunction. The first fistula was supplied by the ASA with additional supply by the dilated PSA connecting with the ASA. Another fistula was supplied by the LSA and the PSA communicating with the ASA. The first case was successfully treated by endovascular treatment with N-butyl cyanoacrylate through the enlarged PSA, whereas the second case was surgically treated by direct obliteration of the fistula. Both patients had good neurological outcome.

Clinical pitfall: false-positive aquaporin-4 IgG leading to misdiagnosis of neuromyelitis optica spectrum disorder in patient with spinal arteriovenous fistula.

We report the cases of a 68-year-old male with a filum terminale arteriovenous fistula (AVF) who was initially misdiagnosed with neuromyelitis optica spectrum disorder (NMOSD) based on imaging findings and false-positive aquaporin-4 IgG (AQP4-IgG). A 68-year-old male presented with slowly progressive weakness and numbness in his bilateral lower extremities. He was initially diagnosed with NMOSD and treated with immunosuppressive therapy based on findings of extensive spinal cord edema on magnetic resonance imaging (MRI) and initial negative spinal angiography as well as positive AQP4-IgG. Despite immunosuppressive treatment, his symptoms progressed slowly. He repeated MRI that showed persistent abnormal signal within the spinal cord. Second spinal angiography revealed filum terminale dural arteriovenous fistula (AVF). Finally, he underwent surgical disconnection of the fistula. Repeated AQP-IgG was reported negative. Although NMOSD and spinal AVFs can share imaging findings on spinal cord MRI, typical clinical features of each disorder are distinct. Identification of AQP4-IgG is the hallmark to confirm a clinical diagnosis of NMOSD; however, different assays can vary in sensitivity and specificity. Although it is rare, false positives can occur especially at low titers. A misdiagnosis of NMOSD and delayed diagnosis of spinal AVF had significant clinical implications because the treatment of spinal AVF is surgical disconnection or endovascular embolization, whereas the treatment for NMOSD includes long-term immunosuppressive therapy. Clinicians should be aware of the potential technical issues in detecting AQP4-IgG especially in the context of patients with atypical presentations for NMOSD.

Arterio Venous Fistula (AVF) of Filum Terminale-MRI Diagnosis - A Case Report

Arteriovenous malformation (AVM) of the spine can present with different symptomatology. This depends upon the region of involvement and with the background of underlying angioarchitectures. AVM occurrence at filum terminale needs special reference as it is not covered under any classifications. Arteriovenous fistula (AVF) can remain undiagnosed because of the location and the way of its presentation. Rodesch et al. has found as 3.2% prevalence in one of their series of arteriovenous shunts management. Selective Digital subtraction angiography (DSA) is required to find out the arterial feeder for its guidelines to the appropriate management. We present 42- years old male who presented with long standing low backache with numbness in both lower limbs. Contrast Magnetic Resonance Imaging (MRI) investigation of Lumbosacral spine diagnosed as a case of having arteriovenous fistula of filum terminale.

Arteriovenous Fistula of the Filum Terminale Misdiagnosed and Previously Operated as Lower Lumbar Degenerative Disease

Filum terminale arteriovenous fistula (FTAVF) presenting as a cause of failed back surgery syndrome is a rare entity. We report a 48-year-old male patient who presented with clinical features of a conus medullaris/cauda equina lesion. He had upper and lower motor neuron signs in both the lower limbs with autonomic dysfunction. The patient was misdiagnosed and was operated twice earlier for lumbar canal stenosis and disc prolapse. After reviewing his clinical and radiological findings a diagnosis of FTAVF was made. He underwent surgery and there was a significant improvement in his neurological functions. We discuss the case and review the literature on FTAVF's.

Filum terminale arteriovenous fistulas: the role of endovascular treatment

The authors describe the clinical presentation, imaging features, and management of patients presenting with filum terminale arteriovenous fistulas (FTAVFs) and the role of transarterial treatment in their management. The authors retrospectively reviewed data obtained in 10 patients with FTAVFs diagnosed between January 1990 and December 2011. Most patients (70%) were male, and the age of the population ranged from 31 to 72 years (mean 58.2 years). Clinical presentation was progressive paraparesis and sensory loss in the lower extremities in 9 cases, back pain in 7, radicular pain in 3, bowel/bladder disturbance in 5, and impotence in 1. The duration of symptoms varied between 2 and 24 months. Initial MRI studies showed intramedullary increased T2 signal, swollen cord, and dilated perimedullary veins in all patients. One patient had syringomyelia, presumably caused by venous hypertension transmitted by the perimedullary venous system. Embolization was attempted in 7 patients and was curative in 6 patients. Surgery was performed in the other 4 patients in whom embolization was unsuccessful or deemed not feasible. There was no treatment-related complication in either group. Symptoms, venous congestion in the cord, and syringomyelia improved on follow-up in all patients. Embolization should be considered the treatment of choice for FTAVFs and can effectively treat the majority of patients presenting with an FTAVF. In a smaller group of patients in whom the angioarchitecture is unfavorable, open surgery is recommended.

Surgical excision of filum terminale arteriovenous fistulae after lumbar fusion: Value of indocyanine green and theory on origins (a technical note and report of two cases)

Background:Intradural filum terminale arteriovenous fistulas (AVFs) are uncommon. We report two cases of this rare entity in which we used indocyanine green (ICG) videoangiography to identify the fistulous connection of each lesion.Case Description:Two male patients presented with unresolved lower extremity weakness and paresthesias following lumbar fusion surgery. In each case, angiography showed an AVF between the filum terminale artery (FTA), the distal segment of the anterior spinal artery (ASA), and an accompanying vein of the filum terminale. A magnetic resonance image (MRI) obtained before lumbar fusion was available in one of these cases and demonstrated evidence of the preexisting vascular malformation. Surgical obliteration of each fistulous connection was facilitated by the use of ICG videoangiography. This emerging technology was instrumental in pinpointing fistula anatomy and in choosing the exact segment of the filum for disconnection.Conclusion:Our findings indicate that intradural filum terminale AVFs may have a congenital origin and that ICG is a useful tool in their successful surgical management. As these cases demonstrate, spine surgeons should remain vigilant in evaluating patients based on their clinical symptomatology, even in the presence of obvious lumbar pathology.

Hemangioblastoma of filum terminale associated with arteriovenous shunting

Background Spinal arteriovenous shunt typically presents in middle age or in the elderly with a strong male predilection. The clinical presentation is usually progressive neurological deficits such as paraparesis or incontinence due to cord edema, although back pain is also a common presentation. Progress of neurological deficit is typically stopped by occlusion of the shunt (surgically or endovascularly), but the return of loss of function may be found in less than half of these patients. In contrast, spinal hemangioblastomas usually occur in adults, and the most common presentation is pain with radiculopathy. Location in the filum terminale is very rare. Case Description After a review of the medical literature, we identified 7 cases of hemangioblastomas arising from the filum terminale ( Am J Neuroradiol. 2005;26:936-945; Acta Neurochir [Wien]. 2000;142:1059-1062; J Neurosurg Sci. 2001;45:58-62; J Clin Neurosci. 2006;13:285-288; Neurosurgery. 1999;44:220-223; Clin Neurol Neurosurg. 1985;87:55-59).We report an additional case of a filum terminale hemangioblastoma occurring in a 64-year-old man with 1 month exacerbation of chronic low back pain. Preoperatively, it was misdiagnosed as filum terminale arteriovenous fistula. Conclusion Even with modern imaging, preoperative diagnosis can still be difficult.