The Safety Profile of Intentional or Iatrogenic Sacrifice of the Artery of Adamkiewciz and Its Vicinity's Spinal Segmental Arteries: A Systematic Review

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

Objective

Minimally 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.

Methods

Between 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.

Results

The 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.

Conclusions

Minimally 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 Coil-Embolization of a Large, Myelon-Compressing Vertebral Metastasis Involving the Artery of Adamkiewicz

Background Metastatic spinal cord compression causes neurologic impairment and pain, potentially improved by decompression surgery at the risk of heavy intraoperative bleeding. Preoperative embolization carries the risk of nontarget embolization, potentially causing spinal ischemia. Current evidence indicates that knowledge of artery of Adamkiewicz (AKA) location and the amount of collateralization may help estimate the risk of postinterventional spinal cord injury.

Case Presentation In this case of a 73-year-old female patient with progression of a large, myelon-compressing vertebral metastasis of L1, protective, blood-flow-controlling occlusion of the proximal-most points of the AKA and segmental spinal arteries was safely performed prior to tumor embolization, surgical decompression, and tumor debulking.

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

OBJECTIVE

The aim of this paper was to identify and characterize all the segmental radiculomedullary arteries (RMAs) that supply the thoracic and lumbar spinal cord.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Comparison of a right versus left sided anterior approach to the thoracic and thoracolumbar spine: A case series

Aims & objectives

Traditionally, a left sided anterior approach has been considered the safest way to access the thoracic and thoracolumbar spine due to avoidance of the inferior vena cava (IVC). We challenge this 'go from the left' dogma by presenting a series of patients who underwent a right sided approach to the thoracic and thoracolumbar spine.

Materials & methods

71 anterior thoracic fusion procedures treated with either a left or right sided approach were identified and retrospectively studied. Demographic information, indication for surgery, intra-operative time, estimated blood loss (EBL), hospital length of stay (LOS), and complications were collected. Patients were further sub divided into groups according to indication for surgery.

Results

57 cases with a right sided approach and 14 cases with a left sided approach were investigated. Four mortalities occurred, all within the right sided approach group among patients who were being for osteomyelitis/discitis. There were statistically significant differences between right and left sided approach groups for operative time and EBL when patients were analysed together favoring the left sided approach. However once subgroup analysis was performed, there were no statistically significant differences between right and left sided approach groups aside from operative time in the HNP group and LOS in the fracture group. Neither group had catastrophic intra-operative vascular injury. Perioperative complications occurred in 22.8% of right sided approach patients and 14% of left sided approach patients.

Conclusions

Our results reinforce the fact that anterior thoracic fusion is a major surgical endeavor that is not without risk. Although there were differences in operative time and EBL between right and left sided approach groups when all patients were analysed together, these were no longer significant with subgroup analysis according to indication for surgery with two exceptions. This may be in part due to low sample size or confounding variables related to indication.

Vascular Myelopathy Secondary to Compression of the Artery of Adamkiewicz From an Intrathecal Catheter: A Technical Case Report

BACKGROUND AND IMPORTANCE

Although catheter-related complications in intrathecal drug delivery systems are relatively common, vascular myelopathy secondary to occlusion of the artery of Adamkiewicz (AoA) from an abutting intrathecal catheter has not yet been reported. In this study, we present a case of this extremely rare presentation, which resolved after decompression of the artery.

CLINICAL PRESENTATION

A 39-year-old woman presented with lower extremity weakness and paresthesia. She had a 20-year history of severe chronic back pain and stable sensory disturbances below T8 as sequelae of multiple injuries after a motor vehicle accident. Three years before presentation in our clinic, she underwent baclofen pump placement because of neuropathic pain refractory to oral medication. After pump placement, she gradually developed myelopathic symptoms and dysautonomia. All medications through the pump were discontinued, but her symptoms continued to progress. Workup included a spinal angiogram that showed that her intrathecal catheter was abutting the left side of the AoA at the T12 level. After interdisciplinary evaluation, it was believed that her clinical presentation was attributable to vascular compression, and she underwent surgical removal of the catheter. Three years later, her symptoms have improved and her neurological examination returned to baseline before the catheter placement.

CONCLUSION

Meticulous, multidisciplinary neurological and radiological evaluations were essential to diagnose the compression of the AoA as the cause of this patient's myelopathy. Although exceedingly rare, direct compression of the AoA by an intrathecal catheter should be on the differential diagnosis when evaluating for causes of vascular myelopathy.

Establishing consensus: determinants of high-risk and preventative strategies for neurological events in complex spinal deformity surgery

PURPOSE

To establish expert consensus on various parameters that constitute elevated risk during spinal deformity surgery and potential preventative strategies that may minimize the risk of intraoperative neuromonitoring (IONM) events and postoperative neurological deficits.

METHODS

Through a series of surveys and a final virtual consensus meeting, the Delphi method was utilized to establish consensus among a group of expert spinal deformity surgeons. During iterative rounds of voting, participants were asked to express their agreement (strongly agree, agree, disagree, strongly disagree) to include items in a final set of guidelines. Consensus was defined as ≥ 80% agreement among participants. Near-consensus was ≥ 60% but < 80% agreement, equipoise was ≥ 20% but < 60%, and consensus to exclude was < 20%.

RESULTS

Fifteen of the 15 (100%) invited expert spinal deformity surgeons agreed to participate. There was consensus to include 22 determinants of high-risk (8 patient factors, 8 curve and spinal cord factors, and 6 surgical factors) and 21 preventative strategies (4 preoperative, 14 intraoperative, and 3 postoperative) in the final set of best practice guidelines.

CONCLUSION

A resource highlighting several salient clinical factors found in high-risk spinal deformity patients as well as strategies to prevent neurological events was successfully created through expert consensus. This is intended to serve as a reference for surgeons and other clinicians involved in the care of spinal deformity patients.

LEVEL OF EVIDENCE

Level V.

Iatrogenic spinal cord ischemia: A patient level meta-analysis of 74 case reports and series

Background

Methods

Results

Conclusions