Hypervascular Metastatic Spine Tumor Angiographic Relationships with the Artery of Adamkiewicz and Other Radiculomedullary Arteries

Analysis of Magnetic Resonance Imaging Perfusion Parameters for the Identification of Spinal Metastatic Tumors with Rich Blood Supply

PURPOSE

To determine the reliability of dynamic magnetic resonance imaging (MRI) perfusion parameters for the evaluation of blood supply to spinal metastatic tumors.

METHODS

A total of 36 patients with spinal metastasis who underwent dynamic contrast-enhanced magnetic resonance spinal perfusion imaging at Tianjin Hospital from December 2018 to December 2020 were reviewed. Subsequently, the patients underwent corresponding preoperative examination using digital subtraction angiography of the spine at the hospital and were divided into 2 groups accordingly. Differences in dynamic MRI perfusion parameters between the 2 groups were analyzed.

RESULTS

There were statistically significant differences between the 2 groups in the quantitative dynamic contrast-enhanced MRI perfusion parameters vascular permeability and plasma volume, as well as semi-quantitative peak enhancement and blood flow ratio parameters.

CONCLUSIONS

Dynamic MRI perfusion may distinguish spinal metastatic lesions with rich blood supply from those with poor blood supply and may help clinicians identify patients that can benefit from invasive spinal angiography and preoperative embolization. This technique may also provide guidance on decision taking for surgery basing on dynamic MRI perfusion parameters.

Comparison of intraoperative blood loss and perioperative complications between preoperative embolization and nonembolization combined with spinal tumor surgeries: a systematic review and meta-analysis

PURPOSE

The present study aimed to comparatively evaluate intraoperative blood loss (IBL) and perioperative complications between preoperative embolization (PE) and nonembolization (NE) combined with spinal tumor surgeries as well as to determine the subgroup of spinal tumor surgeries suitable for PE.

METHODS

A systematic search in PubMed and EMBASE and an additional search by reference lists of the retrieved studies were undertaken by two reviewers. The mean IBL and perioperative complication rate were employed as the effect size in the general quantitative synthesis through direct calculation. Meta-analysis was performed using standardized mean difference (SMD) and weighted mean difference (WMD) of IBL and the odds ratio (OR) of complications. Heterogeneity was assessed using the I2 statistic.

RESULTS

The reviewers selected 17 published studies for the general quantitative synthesis and meta-analyses. The mean IBL of spinal tumor surgeries was 1786.3 mL in the NE group and 1716.4 mL in the PE group. The mean IBL between the two groups was similar. The pooled WMD and SMD of IBL in spinal tumor surgeries was 324.15 mL (95% CI 89.50-1640.9, p = 0.007) and 0.398 (95% CI 0.114-0.682, p = 0.006), respectively. The reduction of the PE group compared with the NE group for the rates of major complications and major hemorrhagic complications were 7.80% and 5.71%, respectively. The risk of PE-related complications in the PE group was only 1.53% more than in the PE group. The pooled OR of major complications in spinal tumor surgeries was 1.426 (95% CI 0.760-2.674; p = 0.269).

CONCLUSIONS

PE may be suitable for spinal tumor surgeries and some subgroups. From the perspective of complications, PE may also be a feasible option for spinal tumor surgeries.

Preoperative Embolization of Spinal Metastatic Tumor: The Use of Selective Computed Tomography Angiography for the Detection of Radiculomedullary Arteries

Introduction

Preoperative embolization for metastatic spinal cord compression (MSCC) has a risk of spinal ischemia. This study aimed to assess the efficacy and safety of preoperative embolization in patients with MSCC and evaluate the use of computed tomography (CT) angiography for the detection of the radiculomedullary arteries (RMA).

Methods

This retrospective study included 20 patients (12 men and 8 women; median age, 66 years), who underwent preoperative embolization before a decompression surgery, which corresponded to 22 embolization procedures. The detection ability of RMA was evaluated using angiography and selective CT angiography. Surgical data including intraoperative blood loss and transfusion were also evaluated.

Results

Six RMAs were identified at the levels of affected vertebrae and one level above and below in the diagnostic spinal angiography. In addition to spinal angiography, adjunctive selective CT angiography allowed visualization of another five RMAs. Overall, 11 RMAs were identified in 9 patients. Preoperative embolization was successfully achieved in all patients. As regards complications related to embolization procedure, palsy exacerbated in one patient (4.5%), which improved postoperatively. During the surgical procedure, the mean intraoperative blood loss was 353.4±254.2 mL without intraoperative transfusion in all patients.

Conclusions

The present study showed small amounts of intraoperative blood loss without any severe complications related to preoperative embolization. Selective CT angiography was a useful technique to detect RMAs and contributed to the safety of preoperative embolization.

The role of percutaneous transarterial embolization in the management of spinal bone tumors: a literature review

PURPOSE

Spinal bone tumors include a heterogeneous broad of primary or metastatic lesions that may present as incidental findings or manifest with painful symptoms and pathological fractures. Optimal management of spine bone lesions is often difficult and treatment algorithms are usually solidly based on surgery. We aimed to evaluate the contribution of trans-arterial embolization in this field, with particular attention to the procedure efficacy, technical difficulties and complications.

METHODS

We present a literature review on the role of trans-arterial embolization in the management of spinal bone tumors, both primary and metastatic, evaluating its contribution as preoperative treatment, palliative procedure and standalone curative strategy.

RESULTS

Trans-arterial embolization provides an important contribution to reducing surgery hemorrhagic risks, offering a better visualization of the operating field, and possibly increasing tumor susceptibility to chemotherapy or radiation therapy. Nonetheless, it plays an important part in pain palliation, with the unquestionable advantage of being easily repeatable in case of necessity. Its curative role as a standalone therapy is still subject of debate, and at the present time, satisfactory results have been recorded only in the treatment of aneurysmal bone cysts.

CONCLUSION

Percutaneous trans-arterial embolization has established as a highly useful minimally invasive procedure in the management of spinal bone lesions, particularly as adjuvant preoperative therapy and palliative treatment.

The relevance of the artery of Adamkiewicz for microsurgical resection of spinal tumors- short overview and case series: Technical note

INTRODUCTION

There is of major interest to know the exact anatomical location of artery of Adamkiewicz (AKA) for many spinal microsurgical procedures, so as to avoid postoperative ischemia of the spinal cord, with further devastating clinical impact.

METHODS AND RESULTS

We detail the interest of preoperative angiography for medullary lesions in our experience. We further report two cases where the AKA was located at the same level and side with the treated lesion. The first case underwent an intracapsular decompression. The second patient undertook radiosurgery by Cyberknife.

CONCLUSION

For spinal tumor where the AKA is exactly on the same level and side, an intracapsular decompression can be safely performed, with an immediate decrease of the symptomatic mass effect, while decreasing the risk of neurological injury. A second valuable alternative in such situations can also be radiosurgery, for small to medium size tumors. In our experience, this proved safe and effective both for tumor and eventual pain control.

Neurologic Complications of Preoperative Embolization of Spinal Metastasis: A Systemic Review of the Literature Identifying Distinct Mechanisms of Injury

BACKGROUND

Preoperative embolization of spinal metastases may improve outcomes of resection by reducing surgical blood loss and operative time. Neurologic complications are rarely reported and the mechanisms leading to injury are poorly described.

METHODS

We present 2 illustrative cases of embolization-related neurologic injury from distinct mechanisms and the findings of a systemic literature review of similar complications according to the PRISMA guidelines.

RESULTS

A 77-year-old man with a history of renal cell carcinoma presented with gait dyscoordination and arm pain/weakness. Magnetic resonance imaging showed a C7/T1 mass causing severe compression of the C7/T1 roots and spinal cord. After embolization and tumor resection/fusion, lethargy prompted imaging showing multiple posterior circulation infarcts believed to be secondary to reflux of embolic particles. A 75-year-old man with renal cell carcinoma presented with L1 level metastasis causing conus compression and experienced paraplegia after superselective particle embolization presumed to be secondary to flow disruption of the artery of Adamkiewicz. Analysis of the literature yielded 6 articles reporting instances of cranial infarction/ischemia occurring in 10 patients, 12 articles reporting spinal cord ischemia/infarction occurring in 17 patients, and 5 articles reporting symptomatic postembolization tumoral swelling in 5 patients.

CONCLUSIONS

Neurologic injury is a risk of preoperative embolization of spinal metastasis from either compromise of spinal cord vascular supply or cranial stroke from reflux of embolic particles. Postprocedural tumor swelling rarely leads to clinical deficit. Awareness of these complications and the presumed mechanisms of injury may aid clinicians in implementing interventions and in counseling patients before treatment.

Comparison of complete and near-complete endovascular embolization of hypervascular spine tumors with partial embolization

OBJECTIVE

Preoperative endovascular embolization of hypervascular spine tumors can reduce intraoperative blood loss. The extent to which subtotal embolization reduces blood loss has not been clearly established. This study aimed to elucidate a relationship between the extent of preoperative embolization and intraoperative blood loss.

METHODS

Sixty-six patients undergoing preoperative endovascular embolization and subsequent resection of hypervascular spine tumors were retrospectively reviewed. Patients were divided into 3 groups: complete embolization (n = 22), near-complete embolization (≥ 90% but < 100%; n = 22), and partial embolization (< 90%; n = 22). Intraoperative blood loss was compared between groups using one-way ANOVA with post hoc comparisons between groups.

RESULTS

The average blood loss in the complete embolization group was 1625 mL. The near-complete embolization group had an average blood loss of 2021 mL in surgery. Partial embolization was associated with a mean blood loss of 4009 mL. On one-way ANOVA, significant differences were seen across groups (F-ratio = 6.81, p = 0.002). Significant differences in intraoperative blood loss were also seen between patients undergoing complete and partial embolization (p = 0.001) and those undergoing near-complete and partial embolization (p = 0.006). Pairwise testing showed no significant difference between complete and near-complete embolization (p = 0.57). Analysis of a combined group of complete and near-complete embolization also showed a significantly decreased blood loss compared with partial embolization (p < 0.001). Patient age, tumor size, preoperative coagulation parameters, and preoperative platelet count were not significantly associated with blood loss.

CONCLUSIONS

Preoperative endovascular embolization is associated with decreased intraoperative blood loss. In this series, blood loss was significantly less in surgeries for tumors in which preoperative complete or near-complete embolization was achieved than in tumors in which preoperative embolization resulted in less than 90% reduction of tumor vascular blush. These findings suggest that there may be a critical threshold of efficacy that should be the goal of preoperative embolization.

Introduction to Diagnostic and Therapeutic Spinal Angiography

This article describes the basic principles of diagnostic and therapeutic spinal angiography as practiced by the author, including catheterization and radioprotection techniques, the selection of endovascular devices and embolization agents, and procedural complications.