Embolization Tactics of Spinal Epidural Arteriovenous Fistulas

Purpose: Spinal epidural arteriovenous fistulas (SEDAVFs) show an epidural venous sac often with venous congestive myelopathy (VCM) due to intradural reflux at a remote level to which a transarterial approach would be difficult. We present 12 cases of SEDAVF with VCM and describe 3 main tactics for effective transarterial embolization.Materials and Methods: Among 152 patients with spinal vascular malformations diagnosed in our tertiary hospital between 1993 and 2019, 12 SEDAVF patients with VCM were included. Three different transarterial embolization tactics were applied according to the vascular configuration and microcatheter accessibility. We evaluated treatment results and clinical outcomes before and after treatment.Results: Transarterial embolization with glue (20–30%) was performed in all patients. The embolization tactics applied in 12 patients were preferential flow (n=2), plug-and-push (n=6), and filling of the venous sac (n=4). Total occlusion of the SEDAVF, including intradural reflux, was achieved in 11 (91.7%) of 12 patients, and partial occlusion was achieved in 1 patient. No periprocedural complications were reported. Spinal cord edema was improved in all patients for an average of 18 months after treatment. Clinical functional outcome in terms of the pain, sensory, motor, and sphincter scale and modified Rankin scores improved during a mean 25-month follow-up (6.3 vs. 3.3, P=0.002; 3.6 vs. 2.3, P=0.002, respectively).Conclusion: Endovascular treatment for 12 SEDAVF patients with VCM achieved a total occlusion rate of 91.7% without any periprocedural complication. The combined embolization tactics can block intradural reflux causing VCM, resulting in overall good clinical outcomes.

Cauda equina arteriovenous fistula supplied by proximal radicular artery and concomitant sacral dural arteriovenous fistula: A case report and literature review

Background: Cauda equina arteriovenous fistulas (AVFs) fed by the proximal radicular artery are exceedingly rare. Spinal dural arteriovenous fistulas (DAVFs) in the sacral region are rare and usually misdiagnosed. We report a case of a cauda equina AVF with concomitant sacral DAVF. We also review the coexistence of multiple types of spinal vascular malformations in a single patient. Case Description: A 54-year-old man presented with progressive weakness of the lower extremities for 1 month. Magnetic resonance imaging (MRI) of the lumbosacral and thoracic spine showed spinal cord congestion, extending from the conus medullaris to the level of T7, and abnormal tortuous and dilated flow void, running from the level of L5 to T12 along anterior surface of the spinal cord. Spinal angiography demonstrated the fistula at the level of L2 below the conus medullaris. Based on intraoperative findings, the cauda equina AVF supplied by the proximal radicular artery with cranial drainage through the enlarged radicular vein was confirmed and successfully obliterated. Another enlarged arterialized radicular vein running parallel to another cauda equina nerve root is observed with unknown origin. After the operation, the patient showed mild improvement of his symptoms. Follow-up MRI and contrast-enhanced MR angiography revealed an another sacral DAVF vascularized by the lateral sacral artery. Conclusion: The coexistence of different spinal vascular malformations in a same patient is extremely rare. Most authors of several studies hypothesized that venous hypertension and thrombosis due to the presence or treatment of the first spinal vascular lesion may produce a second DAVF.

3D DCE-MRA in spinal vascular malformations

Purpose: This study was carried out to investigate whether 3.0T dynamic enhanced 3 dimensional magnetic resonance angiography (3D DCE-MRA) could identify spinal cord vascular malformations efficiently.Material and Methods: 32 suspected cases of spinal vascular disease with MR imaging and clinical symptoms were detected using DCE-MRA. 28 patients were valued through DSA for 3-5 days, and surgical treatment was performed on 24 patients. Results: DCE-MRA was used to examine all the cases which recognized abnormal vascular lesions clearly, and 28 cases were consistent with DSA or surgical diagnosis. The arterial blood supply was evaluated accurately in 28 cases. The findings were correct in 26 cases.Conclusion: 3.0T DCE-MRA features high sensitivity and accuracy in detecting and characterizing SVMs, especially SDAVF.

The History and Development of Endovascular Neurosurgery

Endovasuclar neurosurgery, neuroendovascular surgery and neurointervention are all defined as endovascular diagnosis and treatment of vascular lesions involving the brain and spinal cord using catheters in the DSA (digital subtraction angiography) unite. Based on literature evidences, the field of endovascular neurosurgery has evolved rapidly and successfully over the past half century and has resulted in effective endovascular therapies for carotid-cavernous fistulas (CCFs), intracranial aneurysms, arteriovenous malformations (AVMs), dural arteriovenous fistulas, atherosclerosis of cerebral arteries, acute stroke, carotid artery disease, and vascular tumors of the head, neck, and spinal vascular malformations and tumors. The scope of practice of neurovascular endovascular surgery has become complex, requiring training in specific skill sets and techniques. The evolution of the neuroendovascular field has resulted in the development of program requirements for residency or fellowship education in endovascular neurosurgery.

Thoracolumbar progressive myelopathy due to extra-dural arteriovenous fistula

Context: Arteriovenous dural fistulas are the most common spinal vascular malformations and constitute a reversible cause of progressive myelopathy. This disease affects elderly men and are classically found at the thoracolumbar region. Case report: A 69year-old man was admitted to the Neurology outpatient clinic with weakness in his left inferior limb for the past 10 years; 2 years before the evaluation, the weakness progressed also to the right inferior limb, causing inability to walk, and 1 year after the patient noticed urinary incontinence and sexual dysfunction. Physical evaluation showed grade-II paraparesis with spastic hypertonia; hypoesthesia below T-10 dermatome; hyperreflexia with clonus and Babinski sign in inferior limbs. Investigation with MRI showed abnormal hypersignal within spinal cord from T6-T7 to the medullary cone; CSF sample had hyper protein count without pleocytosis. Before the hypothesis of non- compressive, non-inflammatory and non-infectious myelopathy, we performed a spinal angiography – which diagnosed a dural arteriovenous fistula at the level of T8 connecting spinal with extradural vessels. The patient was then treated by endovascular therapy with fistula embolization. Conclusion: Although being the most common vascular spinal malformation, arteriovenous dural fistulas are rare and underdiagnosed because of their nonspecific symptoms. The aim of treatment is the shunt occlusion but its prognosis depends on the duration and intensity of symptoms before treatment. This report’s aim is to exemplify a typical case of this condition.

Four-dimensional digital subtraction angiography for exploration of spinal cord vascular malformations: preliminary experience

BackgroundThe precise understanding of the angioarchitecture of spinal vascular malformations (SVMs) is often difficult to reach with conventional digital subtraction angiography (DSA). The purpose of our study was to evaluate the potential of four-dimensional DSA (4D-DSA) (Siemens Healthcare) in the exploration of SVMs.MethodsWe retrospectively studied all patients who underwent spinal DSA, including 4D-DSA acquisition, from July 2018 to June 2019 at a single institution. All spinal DSA acquisitions were performed under general anesthesia. 4D-DSA acquisitions were acquired with the protocol '12 s DSA Dyna4D Neuro'. 12 mL of iodixanol 320 mg iodine/mL were injected via a 5 F catheter (1 mL/s during the 12 s 4D-DSA acquisition). Inter-rater (three independent reviewers) and intermodality agreements were assessed.ResultsNine consecutive patients (six men, three women, mean age 55.3±19.8 years) with 10 SVMs (spinal dural arteriovenous fistulas n=3, spinal epidural arteriovenous fistulas n=2, spinal pial arteriovenous fistulas n=2, and spinal arteriovenous malformations n=2; one patient had two synchronous pial fistulas) had spinal DSA, including 4D-DSA acquisition. Inter-rater agreement was good and moderate for the venous drainage pattern and the SVM subtype, respectively. In 9 of 10 cases, the quality of the acquisition was graded as good. Satisfactory concordance between 4D-DSA and the selective microcatheterization was observed in 90% of cases for the location of the shunt point.Conclusion4D-DSA acquisition may be helpful for a better understanding of the angioarchitecture of SVMs. Larger series are warranted to confirm these preliminary results.

First clinical multicenter experience with the new Scepter Mini microballoon catheter

BackgroundBalloon-assisted techniques can improve the endovascular treatment of cerebrospinal vascular malformations. The aim of this study was to report the first clinical multicenter experience with the new Scepter Mini dual-lumen microballoon catheter.MethodsPatients with cerebral or spinal vascular malformations treated with the Scepter Mini at seven European neurovascular centers were retrospectively reviewed. Clinical data, angiographic features of the vascular malformations, procedural parameters including the type of application, navigability, technical failures, complications and embolization success were assessed.ResultsThe usage of 34 Scepter Mini microballoon catheters in 20 patients was analyzed. Most treated malformations (80.0%) were cerebral arteriovenous malformations. Four different applications were reported: embolization via Scepter Mini (n=23, 67.6%), balloon-occlusion with simultaneous embolization via a second microcatheter (n=3, 8.8%), diagnostic angiography with simultaneous balloon-inflation for flow arrest (n=4, 11.8%), and navigation support (n=4, 11.8%). The mean diameter of the blood vessels in which the Scepter Mini was inflated was 1.9±0.5 mm. The navigability of the Scepter Mini was rated as ‘easy’ or ‘very easy’ in 88.2% of cases. Complete occlusion of the malformation was achieved in 60.9% of cases. Technical failures occurred in 4/23 embolization procedures, and all were related to insufficient stability of the balloon within the vessel. No complications related to the Scepter Mini were observed, while unrelated complications occurred in three patients (15.0%).ConclusionsThe Scepter Mini is a promising new device for balloon-assisted embolization of cerebrospinal vascular malformations via small feeders. Beyond embolization, the Scepter Mini can also be used for other applications, such as superselective flow arrest and navigation support.

Clinical and angioarchitectural characteristics of spinal vascular malformations of the cervical spine

OBJECTIVEVascular malformations of the cervical spine are exceedingly rare. To date there have been no large case series describing the clinical presentation and angioarchitectural characteristics of cervical spine vascular malformations. The authors report their institutional case series on cervical spine vascular malformations diagnosed and treated at their institution.METHODSThe authors retrospectively reviewed all patients with spinal vascular malformations from their institution from January 2001 to December 2018. Patients with vascular malformations of the cervical spine were included. Lesions were characterized by their angioarchitectural characteristics by an interventional neuroradiologist and endovascular neurosurgeon. Data were collected on clinical presentation, imaging findings, treatment outcomes, and long-term follow-up. Descriptive statistics are reported.RESULTSOf a total of 213 patients with spinal vascular malformations, 27 (12.7%) had vascular malformations in the cervical spine. The mean patient age was 46.1 ± 21.9 years and 16 (59.3%) were male. The most common presentations were lower-extremity weakness (13 patients, 48.1%), tetraparesis (8 patients, 29.6%), and lower-extremity sensory dysfunction (7 patients, 25.9%). Nine patients (33.3%) presented with hemorrhage. Fifteen patients (55.6%) had modified Rankin Scale scores of 0–2 at the time of diagnosis. Regarding angioarchitectural characteristics, 8 patients (29.6%) had intramedullary arteriovenous malformations (AVMs), 5 (18.5%) had epidural arteriovenous fistulas (AVFs), 4 (14.8%) had paraspinal fistulas, 4 (14.8%) had mixed epidural/intradural fistulas, 3 (11.1%) had perimedullary AVMs, 2 (7.4%) had dural fistulas, and 1 patient (3.7%) had a perimedullary AVF.CONCLUSIONSThis retrospective study of 27 patients with cervical spine vascular malformations is the largest series to date on these lesions. The authors found substantial angioarchitectural heterogeneity with the most common types being intramedullary AVMs followed by epidural AVFs, paraspinal fistulas, and mixed intradural/extradural fistulas. Angioarchitecture dictated the clinical presentation as intradural shunts were more likely to present with hemorrhage and acute onset myelopathy, while dural and extradural shunts presented as either incidental lesions or gradually progressive congestive myelopathy.