Development of Collaterals to the Spinal Cord after Endovascular Stent Graft Repair of Thoracic Aneurysms

A direct aorta to segmental artery bypass for prevention of spinal cord ischemia after endovascular aortic repair

Spinal cord ischemia remains a persistent challenge after endovascular aortic aneurysm repair. We present a novel direct aorta to segmental artery bypass before aneurysm repair in a 64-year-old woman presenting with an enlarging aneurysm following dissection. Through an eighth intercostal incision, a polyester graft was sewn into the aorta using pledgeted sutures. An entry needle was used to directly access the previously treated aortic segment, and the opening was stented and angioplasty was performed to create inflow. Anastomoses were performed to a prominent left T10 segmental artery with a harvested saphenous vein. The patient remained neurologically intact postoperatively and the 1-month follow-up angiography demonstrated bypass patency.

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.

Teaching vascular anatomy: the anatomy we know, the anatomy we see or the anatomy we need?

PURPOSE

This article presents the evolution of the subject of vascular anatomy and discusses the associated clinical applicability.

METHODS

Clinically-driven surgical examples met in our everyday practice were used to depict characteristic anatomical paradoxes raised by the inconsistencies between classical anatomical perception, current imaging modalities and modern surgical techniques.

RESULTS

Consequent anatomy-driven modifications of medical devices comprise a characteristic example of the vivid, modern and meaningful role that anatomy can have on clinical decision-making and improvement of technical and clinical success. Clinical experience provides a feedback that shifts the focus of anatomic research towards new fields of interest, such as the role of arterial collateral networks as therapeutic targets. The clinical feedback brings into light queries and issues where traditional anatomical answers may be vague and inadequate to apply, thereby necessitating further research, refinement and reevaluation.

CONCLUSION

While the traditional teaching of vascular anatomy is based on information and illustrations derived from dissection and prosection courses, the development of modern imaging technologies applied in large numbers of living patients and application of minimally invasive techniques challenge our understanding of what should be perceived as fixed and permanent. Moreover, the recently introduced evidence-based philosophy in anatomy elaborate more robust data which not only update, validate and enrich the existing knowledge of anatomical variations but also enable subgroup analyses with respect to race, age and sex, identifying specific anatomic features associated with a significant impact on patient treatment.

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.

Spinal cord infarction six months after thoracic endovascular aortic repair- A case report

Spinal cord infarction is reported to account for less than 1% of all strokes and is a relatively rare disease. In recent years, thoracic endovascular aortic repair (TEVAR) has become a common treatment for aortic aneurysms, and spinal cord ischemia is one of its complications. Most cases occur in the perioperative period; however, a few cases have been reported in the chronic stage. Here, we report a case of spinal cord infarction, 6 months after TEVAR. A 77-year-old man experienced sudden onset paraparesis following dumbbell exercises and defecation. He had a history of an infectious thoracoabdominal aortic aneurysm treated by TEVAR 6 months prior. Paralysis and disturbance of the thermal pain and tactile sensations of the lower limbs were observed, but proprioception and deep sensation were preserved. Computed tomography (CT) showed no evidence of intraspinal hemorrhage, new aortic dissection, or endoleak around the aortic stent placed from Th11 to L3. Magnetic resonance imaging (MRI) showed intramedullary hyperintensity from Th11 to the conus 2 days after onset. Anticoagulant therapy and rehabilitation were performed, and the lower-limb muscle strength gradually improved. After aortic stenting, particularly including the level of the Adamkiewicz artery, the risk of spinal cord ischemia must be monitored, because spinal circulation depends on collateral circulation.

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

STUDY DESIGN

Systematic review.

OBJECTIVES

There is paucity of consensus on whether (1) the artery of Adamkiewicz (AoA) and (2) the number of contiguous segmental spinal arteries (SSAs) that can be safely ligated without causing spinal cord ischemia. The objective of this review is to determine the risk of motor neurological deficits from iatrogenic sacrifice of the (1) AoA and (2) its vicinity's SSAs.

METHODS

Systematic review of the spine and vascular surgery was carried out in accordance to PRISMA guidelines. Outcomes in terms of risk of postoperative motor neurological deficit with occlusion of the AoA, bilateral contiguous SSAs, or unilateral contiguous SSAs were analyzed.

RESULTS

Ten articles, all retrospective case series, were included. Three studies (total N = 50) demonstrated a postoperative neurological deficit risk of 4.0% when the AoA is occluded. When 1 to 6 pairs of SSAs (without knowledge of AoA location) were ligated, the postoperative neurological deficit risk was 0.6%, as compared with 5.4% when more than 6 bilateral pairs of SSAs were ligated (relative risk [RR] = 0.105, 95% CI 0.013-0.841, P = .0337). For unilateral ligation of SSAs of two to nine levels, the risk of postoperative neurological deficit does not exceed 1.3%.

CONCLUSION

The current best evidence indicates that (1) occlusion of the AoA and (2) occlusion of up to 6 pairs of SSAs is associated with a low risk of postoperative neurological deficit. This limited number of low quality studies restrict the ability to draw definitive conclusions. Ligation of AoA and SSAs should only be undertaken when absolutely required to mitigate the small but devastating risk of paralysis.

Aortic polyaneurysmal disease: case report

We report a 78-year-old man who presents progression of his aneurysmatic pathology with previous abdominal infrarenal aortic surgery 20 years later. The computed tomography (CT) scan showed proximal degeneration of the infrarenal aorta, left iliac aneurysm and a new descending thoracic aneurysm close to the aortic arch. The surgical treatment was staged in two times due to the evolution of the aneurysm measures. First, the thoracic and the infrarenal aneurysms were covered each one with endoprosthesis. Four years later the iliac disease was solved with a branched specific iliac endograft.