Radiculomedullary Artery Research Articles

Coil Embolization of a Ruptured Anterior Spinal Artery Aneurysm Associated with Spinal Cord Arteriovenous Malformation.

The present report describes a patient with spinal cord arteriovenous malformation (AVM) and an associated anterior spinal artery aneurysm presenting with subarachnoid hemorrhage. Diagnostic spinal angiography revealed an intramedullary AVM, located at the T10-T11 level, and a prenidal saccular aneurysm at the junction of the radiculomedullary artery and the anterior spinal axis, fed by the right T8 segmental artery. The patient underwent successful selective coil embolization of the aneurysm. Follow-up angiography 3 months postoperatively showed no recurrence of the aneurysm.

Normal, accessory, and aberrant branches of the common iliac artery: angiographic prevalence and clinical implications.

Catheter angiography remains essential to detect, characterize, and treat many vascular, traumatic, and neoplastic conditions affecting the pelvis, but the angiographic literature rarely mentions the common iliac artery (CIA) and its branches. The "normal" branches of the CIA principally consist of subangiographic rami supplying neighboring structures. Larger branches participate in the vascularization of the psoas muscle and the ureter. Less often, the CIA provides anomalous branches that complement or replace critical neighboring vessels. This study investigates the prevalence, type, and clinical relevance of CIA branches detectable during pelvic angiography. This study analyzes the prevalence of CIA branches in 100 consecutive angiograms that included bilateral CIA injections as well as selective catheterizations of the median sacral artery, both L4 ISAs, and both internal iliac arteries. CIA branches were classified as normal (i.e., neither supplementing nor replacing a normal artery), accessory (i.e., supplementing a normal artery), or aberrant (i.e., replacing a normal artery). Forty-three branches arose from 38 CIAs (19% of CIAs) in 30 patients (30% of patients), including 20 normal branches (46.5%), 21 aberrant branches (48.8%), and 2 accessory branches (4.7%). Each of the 15 patients with aberrant branches had at least one anomalous vessel capable of providing a radicular or radiculomedullary artery. CIA branches were present in 30% of patients undergoing spinal angiography. While most normal branches were diminutive and clinically irrelevant, CIAs also provided vessels able to vascularize pelvic and vertebral structures, including the spinal cord or a spinal vascular malformation in 16% of cases. Our study therefore confirms that CIA injections represent an essential component of pelvic and spinal angiography.

FACTFINDERS FOR PATIENT SAFETY: Minimizing risks with cervical epidural injections

This series of FactFinders presents a brief summary of the evidence and outlines recommendations to minimize risks associated with cervical epidural injections.Evidence in support of the following facts is presented.Minimizing Risks with Cervical Interlaminar Epidural Steroid Injections – 1) CILESIs should be performed at C6-C7 or below, with C7-T1 as the preferred access point due to the more generous dorsal epidural space at this level compared to the more cephalad interlaminar segments. This reduces the risk of the minor complication of dural puncture and the major complication of spinal cord injury due to inadvertent needle placement. 2) LF gaps are most prevalent in the midline cervical spine. This can result in diminished tactile feedback with loss of resistance (LOR), increasing the risk for inadvertent dural puncture or spinal cord injury. Based on current evidence, needle placement in the paramedian portion of the interlaminar space is safest to avoid LF gaps. 3) An optimal AP trajectory view and the physician's ability to discern engagement in the LF and subsequent LOR are crucial. Confirmation of minimal needle insertion depth relative to the ventral margin of the lamina with either a lateral or contralateral oblique (CLO) safety view is critical to minimize the risk of inadvertently inserting the needle too ventral. 4) There have been closed claims and case reports of patients who have suffered catastrophic neurologic injuries while receiving CILESIs under deep sedation. If sedation is administered, the least amount necessary should be utilized to ensure the patient can provide verbal feedback during the procedure. 5) CILESIs are an elective procedure; therefore, necessity and likelihood of benefit must be foremost considerations. Current guidelines recommend holding ACAP therapy before CILESIs due to the potentially catastrophic complications associated with epidural hematoma (EH) formation. However, there is also a risk of severe systemic complications with ceasing ACAP in specific clinical scenarios. The treating physician is obligated to determine if the procedure is indicated and can ultimately decide to delay the intervention or not perform the procedure if the benefit does not outweigh the risks.Minimizing Risks with Cervical Transforaminal Epidural Steroid Injections – the Role of Preprocedural Review of Advanced Imaging -- Variations in vascular anatomy may warrant a modified approach to CTFESI. Preprocedural review of cross-sectional imaging can provide critical information for safe injection angle planning specific to individual patients and may help to decrease the risk of unintended vascular events with potentially catastrophic outcomes.Safety of Multi-level or Bilateral Fluoroscopically-Guided Cervical Transforaminal Epidural Steroid Injections -- Safe performance of a CTFESI procedure requires the ability to detect inadvertent arterial injection. Contrast medium placed into the epidural space and/or along the exiting spinal nerves during an initial CTFESI may obscure the detection of inadvertent cannulation of a radiculomedullary artery by a subsequent CTFESI. While no available literature directly addresses the potential risk that exists with a multi-level or bilateral CTFESI, caution is still warranted.

Occlusion of vertebral artery and anterior spinal artery in cervical facet dislocation: a prospective study using computed tomography angiography.

A prospective study. To investigate the incidence of vertebral artery (VA) occlusion and whether anterior spinal artery (ASA) is occluded in cervical facet dislocation. University hospital, China. During a 2-year period, 21 conventional patients with cervical facet dislocation were prospectively enrolled. All patients received computed tomography angiography (CTA) to assess the patency of the VA, anterior radiculomedullary arteries (ARAs), and ASA at the time of injury. Clinical data were documented, including demographics, symptomatic vertebrobasilar ischemia, American Spinal Injury Association Impairment Scale (ASIA) grades, and ASA and VA radiological characteristics. VA unilateral occlusion occurred in 5 of 21 patients (24%), including 2 with unilateral facet dislocation and 3 with bilateral facet dislocation. No ASA occlusion was found in all 21 patients, including 5 with VA unilateral occlusion. No patients had symptomatic vertebrobasilar ischemia. VA occlusion occurs in approximately one-fourth of cervical facet dislocations, with infrequent symptomatic vertebrobasilar ischemia. ASA is not occluded following cervical facet dislocation, even with unilateral VA occlusion.

Case Report: Percutaneous intercostal artery catheterization to treat a difficult-to-access spinal dural arteriovenous fistula

Spinal dural arteriovenous fistulas (SDAVF) are a subtype of spinal arteriovenous malformation (AVM). Although rare, SDAVF are the most common spinal vascular malformations and have potential devastating neurologic consequences, sometimes irreversible. Originally, they were treated with surgery alone, however endovascular treatment of SDAVF has evolved recently with good results and the understanding of the anatomy plays a key role. The feeder vessel of the AV shunt is supplied by the radiculomedullary or radiculopial artery, the shunt is usually located within the root sleeve of the dura and the SDAVF is drained by the medullary vein via retrograde flow. Generally the endovascular approach uses the catheterization of the segmental arteries; however, aortic thoracolumbar aneurysms can render endovascular access difficult and risky. We present a case where an SDAVF in woman with aneurysmal dilation of the descending aorta and a mural thrombus was successfully treated through percutaneous catheterization of intercostal artery.

Endovascular occlusion of segmental arteries feeding the anterior spinal artery to stage endovascular thoracoabdominal aortic repair

ObjectiveMinimally invasive segmental artery coil embolization was introduced to prevent spinal cord ischemia after endovascular repair of thoracoabdominal aortic aneurysms. There is no consensus on whether the endovascular occlusion of segmental arteries feeding directly the anterior radiculomedullary artery and anterior spinal artery can be safely performed without causing spinal cord ischemia. Our aim was to investigate the feasibility and clinical impact of endovascular occlusion of segmental arteries supplying the anterior spinal artery during minimally invasive segmental artery coil embolization in patients with thoracoabdominal aortic aneurysms. MethodsBetween January 2018 and July 2020, 54 patients (36 male; mean age, 71.1 ± 9.3 years) underwent direct embolization of segmental arteries feeding the anterior radiculomedullary artery before endovascular repair of thoracoabdominal aortic aneurysms. End points included technical success of minimally invasive segmental artery coil embolization of segmental arteries, anterior radiculomedullary artery, neurological complications, and in-hospital mortality after minimally invasive segmental artery coil embolization and endovascular repair of thoracoabdominal aortic aneurysms. ResultsThe thoracoabdominal aortic aneurysm classification was type I (n = 8), type II (n = 24), type III (n = 11), and type IV (n = 11). During minimally invasive segmental artery coil embolization, 388 segmental arteries were occluded, each patient having 7.2 ± 3.1 coiled segmental arteries occluding 64.5% (25-100%) of open segmental arteries within the treated aortic segment. Altogether, 66 anterior radiculomedullary arteries were seen originating between Th8 and L3 levels from 85 (21.9%) segmental arteries. In 10 patients (18.5%), 2 large anterior radiculomedullary arteries were identified, and 1 patient (1.9%) showed 3 anterior radiculomedullary arteries on the spinal arteriography. No spinal cord ischemia or procedure-related complications occurred after minimally invasive segmental artery coil embolization. After 47.9 ± 39.4 days, all patients received endovascular repair of their thoracoabdominal aortic aneurysms. There was no in-hospital mortality. One male patient developed incomplete temporary spinal cord ischemia after endovascular repair. ConclusionsMinimally invasive segmental artery coil embolization of segmental arteries feeding the anterior spinal artery in patients with thoracoabdominal aortic aneurysms to prevent spinal cord ischemia after endovascular repair is feasible and clinically safe.

Preoperative embolisation of renal cell carcinoma metastases to the spine - evaluation of procedural and clinical outcome.

Renal cell carcinoma (RCC) is the fourth most common metastatic tumour of the spine. RCC metastases are highly vascular and might cause life-threatening intraoperative bleeding. That is why preoperative embolisation is performed to reduce intraoperative blood loss. The aim of this study was to evaluate the procedural and clinical outcomes of preoperative embolisation of RCC metastases to the vertebral column. In this single-centre retrospective study, data of 59 consecutive patients undergoing endovascular treatment prior to surgical resection were collected and evaluated. In all cases superselective catheterisation and occlusion of feeding vessels was attempted and performed if deemed safe and possible. Completeness of embolisation, procedural details, and the complication rate were evaluated. Surgical procedures were carried out within 48 hours after embolisation. The surgical approach was dependent on the anatomical site and osseous destruction. Intraoperative blood loss was estimated. Fifty-nine patients with a mean age of 63 years were included. Complete embolisation was successful in 76% (45/59) and partial in 15% (9/59). Microspheres were the most commonly used embolic material. In 5 cases (8%) safe occlusion was not possible due to the radiculomedullary artery originating from the same pedicle as the tumour. Minor complications (vomiting, increased pain) occurred in 8 patients. Paraplegia (one transient and one permanent) was noted in 2 cases. Estimated intraoperative blood loss was 830 ± 410 ml. The results of our study show that preoperative embolisation is a feasible and effective method with a relatively high rate of occlusion and low complication rate.

Ruptured Cervical Radiculomedullary Artery Mycotic Aneurysm Presenting with Intracranial and Spinal Subarachnoid Haemorrhage: A Case Report

Ruptured Cervical Radiculomedullary Artery Mycotic Aneurysm Presenting with Intracranial and Spinal Subarachnoid Haemorrhage: A Case Report

Utility of intra-procedural cone-beam computed tomography imaging for the determination of the artery of Adamkiewicz suspected by angiography during transarterial embolization for hemoptysis.

To evaluate the role of cone-beam computed tomography (CT) performed for the determination of the artery of Adamkiewicz (AKA) suspected by angiography during trans-catheter bronchial artery embolization for hemoptysis. In this retrospective study, 17 patients with hemoptysis who underwent cone-beam CT for evaluation of the AKA prior to arterial embolization from December 2014 to March 2022 were included. During the angiographic session, two interventional radiologists selected the possible AKAs that were defined as obscured hairpin-curved vessels arising from the dorsal branch of the intercostal arteries and running towards the midline in the arterially enhanced phase. Contrast-enhanced cone-beam CT was performed as an adjunct to angiography to determine whether the indefinite AKA was a real AKA based on whether it was found to connect to the anterior spinal artery. Selective cone-beam CT was performed at 17 possible AKAs detected by selective arteriogram of the intercostal artery (ICA). Cone-beam CT allowed for the determination of AKAs in 16 cases (94.1%). As a result of cone-beam CT findings, 9 of 16 study arteries (56.3%) were judged as definite AKAs, and the remaining 7 (43.7%) were judged as definitely not AKAs but as the musculocutaneous branching from the dorsal branch of the ICA. In 1 of 17 cases (5.9%), cone-beam CT could not determine the AKA because of poor image quality caused by inadequate breath holding. An additional anterior radiculomedullary artery arising from the dorsal branch of the lower ICA because of the inflow of the contrast medium through the anastomosis was detected in one case by conebeam CT but not by angiography. Intraprocedural enhanced cone-beam CT performed as an adjunctive technique to angiography is sufficient for confident determination of the AKA, which is essential for the operators to perform accurate and safe arterial embolization for hemoptysis.

Feasibility of Direct Intercostal and Lumbar Artery Revascularization to Prevent Spinal Cord Ischemia Associated with Endovascular Thoracoabdominal Aortic Repair

Despite advances in complex endovascular aortic repair techniques, spinal cord ischemia (SCI) is still a devastating complication following endovascular thoracoabdominal aortic repairs. Current preventive strategies such as staged repair, temporary sac perfusion, hemodynamic management, and spinal drainage, focus on augmentation of spinal perfusion through collateral networks. Novel strategies to preserve key intercostal/lumbar arteries have been described including endovascular incorporation of fenestrations/branches and extra-anatomic bypass. We report our early results of patients who underwent direct intercostal/lumbar artery revascularization using endovascular or extra-anatomic approaches for fenestrated-branched endovascular aortic repairs (FBEVAR). A retrospective review of consecutive patients who underwent FBEVAR with intercostal/lumbar artery revascularization from 2018 to 2022 was performed. Patient characteristics, intraoperative details, and outcomes including SCI and branch occlusions were evaluated. Among 318 patients who underwent FBEVAR during the study period, 12 patients were included in the study. Aortic pathologies consisted of degenerative aneurysms (33%), postdissection aneurysms (33%), extensive penetrating aortic ulcers with intramural hematoma (25%), and visceral patch pseudoaneurysm (8%). Full thoracoabdominal coverage was required in eight patients and supraceliac coverage >10 cm was required in four. Nine patients received endovascular incorporation (Fig 1), including directional branches (5/9), unstented fenestrations (2/9), and stented fenestration (1/9). Three patients received extra-anatomic subcutaneous femoral-to-radicular artery bypass using a composite graft of polytetrafluoroethylene and saphenous vein (Fig 2). Our institutional SCI prevention protocol, consisting of prophylactic cerebral spinal fluid drain for high-risk patients, hemodynamic augmentation, and oxygen supplementation, was followed. Prophylactic cerebral spinal fluid drain was placed in nine patients. One patient had unsuccessful drain placement attempts. Two patients who had selective angiography identifying the great anterior radiculomedullary artery, did not undergo drain placement. Total number of target vessels for FBEVAR was 4.2 with a fluoroscopy time 66 ± 31 minutes, and contrast usage of 109 ± 51 mL. There were no in-hospital mortalities. One patient died of intracranial hemorrhage after sustaining a fall from a ladder 32 days after discharge. Tarlov grade II SCI were seen in two patients (one endovascular, one extra-anatomic bypass), which resolved before discharge. At median follow-up of 13 months (range, 13 days to 37 months), three patients had thrombosed intercostal/lumbar branches (one extra-anatomic bypass, two endovascular branches) with no new SCI symptoms. In patients at high risk for SCI undergoing FBEVAR, direct revascularization of an intercostal or lumbar artery is feasible using endovascular or extra-anatomic bypass approach. Further studies are planned to identify key contributing intercostal and lumbar arteries and optimization of revascularization strategies.Fig 2Extra-anatomic, profunda femoris to L1 radicular artery bypass using a composite polytetrafluoroethylene-saphenous vein conduit.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Intraoperative DSA-guided minimal approach for craniocervical junction DAVFs obliteration.

Dural arteriovenous fistulas (DAVFs) are a group of diseases involving problematic shunts between dural arteries and venous structures such as sinuses, meningeal veins, or even cortical veins. To focus on craniocervical junction dural arteriovenous fistulas (DAVFs), we introduce a minimally invasive technique with midline incision combined with intraoperative digital subtraction angiography (DSA). This hybrid technique can minimize the incision wound to an average of 6 cm which leads to less destruction and lower risk of adverse events. Using this minimally invasive approach, surgical obliteration was achieved in 6 patients with craniocervical junction DAVFs. A minimal midline incision was made over the C1-2 level, measuring approximately 5 to 7 cm in length. C1 hemilaminectomy was performed for DAVF obliteration followed by intraoperative DSA for confirmation of complete obliteration. Among these 6 patients, the radiculomedullary artery was the most common feeding artery. The mean length of the operation (including DSA performance) was 6.5 ± 1.4 h. None of these cases showed cerebrospinal fluid leakage or exacerbation of neurological symptoms after the operation. Using intraoperative DSA, the minimally invasive technique offers more precise but less destructive access than conventional far lateral suboccipital craniotomy. Most importantly, intraoperative DSA provided verification of complete closure for shunts that could not be examined for indocyanine green (ICG) dye because the microscope did not have a clear line of sight. In our experience, this technique shows encouraging results of fistula obliteration.

Dissecting a radiculomedullary artery as an infrequent cause of low back pain: illustrative case.

There is currently no case described in the literature of epidural hematoma associated with subarachnoid hemorrhage due to dissection of a spontaneous radiculomedullary artery at the lumbar level and therefore its incidence and prevalence are not known. However, its etiology is thought to be similar and may not be diagnosed given its nonspecific symptomatology. The authors present the case of an adult patient who consulted the emergency department for 2 weeks of low back pain. On physical examination there were negative signs of radiculopathy without neurological focalization. The patient was evaluated by neurosurgery via thoracic and lumbosacral spine magnetic resonance imaging, with findings of epidural hematoma associated with subarachnoid hemorrhage in the lumbosacral region. After that, panangiography was done. In the study, it was possible to visualize a dissection of the radicular artery at the L2 level. The patient was not a candidate for surgical management and continued with medical pain management. The patient has a good clinical evolution and was discharged. The aim of the present case is to describe a unique case of radiculomedullary artery dissection as a cause of spontaneous epidural hematoma associated with a subarachnoid hemorrhage in the lumbar region.

Anatomical study of the thoracolumbar radiculomedullary arteries, including the Adamkiewicz artery and supporting radiculomedullary arteries.

The aim of this paper was to identify and characterize all the segmental radiculomedullary arteries (RMAs) that supply the thoracic and lumbar spinal cord. All RMAs from T4 to L5 were studied systematically in 25 cadaveric specimens. The RMA with the greatest diameter in each specimen was termed the artery of Adamkiewicz (AKA). Other supporting RMAs were also identified and characterized. A total of 27 AKAs were found in 25 specimens. Twenty-two AKAs (81%) originated from a left thoracic or a left lumbar radicular branch, and 5 (19%) arose from the right. Two specimens (8%) had two AKAs each: one specimen with two AKAs on the left side and the other specimen with one AKA on each side. Eight cadaveric specimens (32%) had 10 additional RMAs; among those, a single additional RMA was found in 6 specimens (75%), and 2 additional RMAs were found in each of the remaining 2 specimens (25%). Of those specimens with a single additional RMA, the supporting RMA was ipsilateral to the AKA in 5 specimens (83%) and contralateral in only 1 specimen (17%). The specimens containing 2 additional RMAs were all (100%) ipsilateral to their respective AKAs. The segmental RMAs supplying the thoracic and lumbar spinal cord can be unilateral, bilateral, or multiple. Multiple AKAs or additional RMAs supplying a single anterior spinal artery are common and should be considered when dealing with the spinal cord at the thoracolumbar level.

Intra-arterial injection of particulate corticosteroids: mechanism of injury.

Mechanism of neurologic complications after epidural spinal injections (ESI) of particulate steroids at the cervical spine include intrathecal injection, epidural hematoma, direct spinal cord injury, and brain stem or cord infarction due to an arterial spasm or inadvertent intra-arterial injection of particulate steroids. At the lumbar spine, there is evidence that a spinal cord infarction secondary to an inadvertent intra-arterial injection of particulate steroids through a transforaminal approach is the leading mechanism.Variations in the arterial supply of the spinal cord help to understand how a lumbar ESI may lead to a spinal cord infarction at the thoracic level. A radiculomedullary artery arising from the lumbar or sacral spine may participate to the supply of the spinal cord. All radicular and radiculomedullary arteries penetrate the spinal canal through the intervertebral foramen. Therefore, its catheterization carries a risk of inadvertent intraarterial injection. An ex vivo animal study has shown that particulate steroids injected in the blood stream produce an immediate and unexpected change of red blood cells into spiculated cells which aggregate and cause arterioles obstruction, while no particulate steroid macroaggregates or vascular spasm were observed. Rare instances of neurologic complications also occurred after ESI performed through a posterior approach. All occurred in previously operated on patients suggesting a pathologic role for the epidural scar.

Insufficient blood flow in the radiculomedullary artery may cause cervical spinal cord dysfunction: A case report

Insufficient blood flow in the radiculomedullary artery may cause cervical spinal cord dysfunction: A case report

Safety of Dexamethasone in Transforaminal Epidural Steroid Injections: A Case of Temporary Paraplegia Caused by Injection of Lidocaine and Dexamethasone Into a Lumbar Radiculomedullary Artery, With No Neurologic Sequelae

Safety of Dexamethasone in Transforaminal Epidural Steroid Injections: A Case of Temporary Paraplegia Caused by Injection of Lidocaine and Dexamethasone Into a Lumbar Radiculomedullary Artery, With No Neurologic Sequelae

The Dominant Anterior Thoracic Artery of the Spinal Cord.

Dominant radiculomedullary arteries such as the artery of lumbar enlargement and the artery of cervical enlargement are well-documented. However, variability exists as to the size, number, and location of other radiculomedullary arteries contributing supply to the anterior spinal artery. The aim of this anatomic study was to document the prevalence and characteristics of the dominant anterior thoracic artery in cadaveric specimens. Microsurgical dissection of cadaveric human spinal cord specimens (n = 50) was conducted. The artery of lumbar enlargement was injected with colored latex until the small-caliber arterial vessels were filled. The dominant anterior thoracic artery was identified, injected, and filled with diluted industrial paint. The course, diameter, and location of the dominant anterior thoracic artery, artery of lumbar enlargement, and artery of cervical enlargement were documented. The artery of lumbar enlargement was identified between T3 and L2 in all 50 specimens (100%), and the artery of cervical enlargement was identified in 84% of specimens (42/50). At least 1 dominant anterior thoracic artery distinct from the artery of lumbar enlargement and the artery of cervical enlargement was identified between T1 and T11 in 47 of the 50 specimens (94%). The most frequent origin of the dominant anterior thoracic artery was at the level of T4 on the left. The average size of the dominant anterior thoracic artery was 0.446 mm (range, 0.300-0.759 mm on the left and 0.270-0.569 mm on the right). A dominant anterior thoracic artery is present in 94% of individuals. Variations of the arterial supply to the anterior thoracic cord are of great importance due to their implications for ischemic events as well as surgical and endovascular procedures.

Efficacy of preoperative embolization for metastatic spinal tumor surgery using angiographic vascularity assessment.

Preoperative embolization (PE) for metastatic spinal tumors is a method of minimizing intraoperative blood loss during aggressive surgery. This study specified angiographic standards and investigated the influence of these and other factors on blood loss in patients with spinal metastases and various pathologies. The cohort comprised 126 consecutive patients receiving PE from 2015 to 2021. Their clinical, surgical, and angiographic characteristics were reviewed. Standard angiographic grading was used for vascularity assessment. Degree of embolization was divided into complete (≥ 90%), near complete (67 to < 90%), and partial (< 67%). Logistic regression analysis was used to investigate factors predictive of massive blood loss (> 2500 mL). A proportional odds model was used to assess factors predictive of the degree of embolization. Mean intraoperative blood loss was 1676 mL. Among the patients, 62 had hypervascular tumors and 64 had nonhypervascular tumors, according to the angiographic classification. Intraoperative blood loss differed significantly with embolization degree, both overall (p < 0.001) and in the hypervascular and nonhypervascular groups (p = 0.01 and 0.03). Angiographic hypervascularity, spinal metastasis invasiveness index, and embolization degree were significant predictors of massive blood loss in univariate analysis, but only embolization degree was significant in multivariate analysis. Only the presence of the radiculomedullary artery at the target level was significant in both the univariate and multivariate analyses for embolization degree. In addition to pathological classification, angiographic vascularity assessment is valuable. Although complete embolization is a reasonable goal, it is challenging to achieve in cases of visible radiculomedullary artery. • Angiography has a supplementary role in vascularity assessment for spinal metastatic surgery. • Better embolization degree is associated with less intraoperative blood loss in both angiographic hypervascular and nonhypervascular groups. • Presence of radiculomedullary artery in the target level causes worse embolization outcome.

Technical video: Onyx-18 embolization of spinal epidural arteriovenous Fistula using the scepter-Mini balloon catheter.

Spinal arteriovenous fistulas (AVFs) account for approximately 70% of all vascular spinal malformations and commonly develop in the lateral epidural space at the epidural /radicular venous junction. The fistula is located close to the spinal nerve root where a radiculomeningeal artery shunts to a radicular vein. Increased venous pressure leads to decreased spinal venous drainage and venous congestion causing progressive myelopathy, bowel/bladder incontinence and erectile dysfunction. Treatment consists of surgical occlusion of the intradural vein, or endovascular embolization, which has a reported success rate of 25%-75%.1 Endovascular failure can occur with inadequate embolic penetration of the nidus and the proximal segment of the draining vein, or premature reflux of the liquid embolic agent.The use of a dual-lumen balloon microcatheter offers advantage in these cases given the ability to push liquid embolysate more distally during balloon inflation. The Scepter Mini is a new dimethyl-sulfoxide (DMSO)-compatible dual-lumen balloon microcatheter with a distal-tip outer diameter of 1.6 Fr and a nominal balloon diameter of 2.2 mm, facilitating atraumatic navigation and safer balloon inflation. Limited neurointerventional experience using the Scepter Mini in predominantly cerebrovascular cases has reported favorable navigability and flow arrest2, 3 Although Onyx is rarely used for spinal AVF embolization, success has been reported considering the well-known favorable experience in cerebral cases.1, 4, 5We present one of the first cases of Onyx embolization of a spinal dural AVF through a Scepter Mini in a patient with progressively worsening lower extremity sensorimotor dysfunction. Operators should be aware of radiculomedullary arteries arising at the same level or at adjacent levels to avoid unintentional Onyx migration during balloon inflation.

The Relevance of the Adamkiewicz Artery Anatomical Variations for Resection of Spinal Tumors

The artery of Adamkiewickz (AKA) is the most prominent radiculomedullary artery derived between T9 to L2 vertebral segments, supplying oxygenated blood to the caudal thoracic and lumbar regions of the spinal cord. Anatomical comprehension of this artery is important to avoid serious neurological complications during surgery treating intraspinal tumors and spinal vascular malformations. This study aimed to review the published literature on iatrogenic injury to anatomical variations in the AKA, clinical significance, as well as assess diverse radiological imaging techniques used to visualize this vessel before surgery. A retrospective study was performed from 2016 to 2021 using PubMed as our primary search engine, to better focus on the recent five‐year range findings. As multiple variations related to the AKA are found in the various demographics around the world, surgical approaches can be improved to preserve the neurovascular structures. Thus, understanding the importance of neurovascular anatomical variations will help to comprehend spinal cord irrigation which is imperative for the safe and effective therapeutic planning and avoidance of complications.