Preoperative Embolization of Spinal Tumors: A Systematic Review and Meta-Analysis

A case of preoperative embolization for a giant hypervascular pancreatic serous cystic neoplasm in pancreaticoduodenectomy

BACKGROUND

Preoperative vascular embolization is an effective strategy for managing meningiomas, neck paragangliomas, renal cell carcinomas, and bone metastasis by reducing the intraoperative bleeding volume and operation time. Although hypervascular tumors also occur in the pancreas, preoperative embolization for these tumors is not commonly practiced. We herein present a case of a giant serous cystic neoplasm (SCN) of the pancreas with significant arterial vascularity that was managed with preoperative interventional radiology and subsequently resected via pancreaticoduodenectomy.

CASE PRESENTATION

A 60-year-old man presented with an 8-cm hypervascular tumor located at the head of the pancreas, identified as an SCN on pathologic examination. The tumor had increased by 13 mm over 5 years, necessitating surgical intervention. Computed tomography revealed a substantial blood supply to the tumor from the dorsal pancreatic artery and gastroduodenal artery, both branches of the superior mesenteric artery. To mitigate the risk of severe intraoperative bleeding from this giant hypervascular tumor, branches of the dorsal pancreatic artery and gastroduodenal artery were embolized using metallic coils and further secured using a gelatin sponge 1 day prior to pancreatectomy. During the laparotomy, the tumor appeared to have decreased in size, likely because of reduced distension and congestion. Despite significant adhesions to surrounding tissues secondary to prolonged compression and inflammation, the pancreaticoduodenectomy was completed successfully in 5 h and 15 min with blood loss of 763 mL. The patient was discharged on postoperative day 15 without complications.

CONCLUSIONS

Preoperative arterial embolization for hypervascular pancreatic tumors might control the risk of massive intraoperative bleeding, contributing to a favorable postoperative outcome. Utilizing interventional radiology for preoperative inflow control is one of the beneficial strategies for pancreatectomy in patients with a giant SCN.

A Multidisciplinary Update on Treatment Modalities for Metastatic Spinal Tumors with a Surgical Emphasis: A Literature Review and Evaluation of the Role of Artificial Intelligence

Spinal metastases occur in up to 40% of patients with cancer. Of these cases, 10% become symptomatic. The reported incidence of spinal metastases has increased in recent years due to innovations in imaging modalities and oncological treatments. As the incidence of spinal metastases rises, so does the demand for improved treatments and treatment algorithms, which now emphasize greater multidisciplinary collaboration and are increasingly customized per patient. Uniquely, we discuss the potential clinical applications of AI and NGS in the treatment of spinal metastases. Material and Methods: A PubMed search for articles published from 2000 to 2023 regarding spinal metastases and artificial intelligence in healthcare was completed. After screening for relevance, the key findings from each study were summarized in this update. Results: This review summarizes the evidence from studies reporting on treatment modalities for spinal metastases, including minimally invasive surgery (MIS), external beam radiation therapy (EBRT), stereotactic radiosurgery (SRS), CFR-PEEK instrumentation, radiofrequency ablation (RFA), next-generation sequencing (NGS), artificial intelligence, and predictive models.

The effect of preoperative embolization on giant cell tumors of the bone localized in the iliosacral region of the pelvis

INTRODUCTION

Giant cell tumors of the bone (GCTB) are aggressive neoplasms, with rare occurrences in the posterior pelvis and sacral area. Surgical challenges in this region include the inability to apply a tourniquet and limited cementation post-curettage due to proximity to neurovascular structures, leading to potential complications. This case-control study explores the impact of preoperative embolization on GCTB located in the iliosacral region.

METHODS

Five surgeries (January-December 2021) for pelvic GCTB (3 sacrum, 2 posterior ilium) were performed on four patients. Diagnosis was confirmed through preoperative CT-guided biopsies. One surgery involved curettage with PMMA cement filling, while four surgeries had curettage without cavity filling. Preoperative embolization of the tumor feeding vessel occurred approximately 16 h before surgery in two cases. Denosumab treatment was not administered.

RESULTS

Tumor volume, assessed by preoperative MRI, was comparable between patients with and without preoperative embolization (p = .14). Surgeries without embolization had a mean intraoperative blood loss of 3250 ml, erythrocyte transfusion volume of 1125 ml, and a mean surgical time of 114.5 min for two surgeries. Surgeries with preoperative embolization showed a mean intraoperative blood loss of 1850 ml, no erythrocyte transfusion requirement, and a mean surgical time of 68 min.

CONCLUSION

Curettage of GCTB in the posterior pelvis and sacrum presents challenges, with significant intraoperative blood loss impacting surgical time and transfusion needs. Preoperative embolization may be beneficial in reducing blood loss during surgery in these cases.

Computed Tomography Perfusion Combined With Preoperative Embolization for Reducing Intraoperative Blood Loss in Separation Surgery for Thoracolumbar Metastases

STUDY DESIGN

A prospective consecutive case study.

OBJECTIVE

This study aimed to assess the accuracy of computed tomography perfusion (CTP) in evaluating the vascularity of thoracolumbar metastases and to determine the impact of combining CTP with preoperative embolization on reducing intraoperative blood loss during separation surgery.

SUMMARY OF BACKGROUND DATA

Surgery for thoracolumbar metastases is a complex procedure with the potential for substantial blood loss. Therefore, assessing tumor vascularity before surgery and taking measures to minimize intraoperative blood loss is essential.

METHODS

A total of 62 patients with thoracolumbar metastases were prospectively enrolled. All patients underwent separation surgery using the posterior approach. Before surgery, the vascularity of the metastases was evaluated using CTP. On the basis of the CTP results, patients were categorized into hypervascular and hypovascular groups. Preoperative angiography and embolization were performed for the hypervascular group. Clinical data were abstracted, including intraoperative blood loss, perioperative complications, visual analog scale score, neurological status, and the accuracy of vascularity evaluation by CTP confirmed by angiography. χ 2 testing was used to compare categorical variables, whereas independent sample t tests were used to compare continuous variables, with paired t tests used to assess differences from preoperative to postoperative time points.

RESULTS

The mean intraoperative blood loss was 485±167 and 455±127.6 mL in the two groups, respectively. The accuracy of vascularity evaluation by CTP was 100%. In the hypervascular group, 80.6% of the patients experienced at least one level of improvement in neurological status, while the hypovascular group had 81.5% of patients with similar improvement. None of the patients experienced neurological deterioration. There was a significant reduction in visual analog scale scores in both groups after the operation.

CONCLUSIONS

The vascularity of thoracolumbar metastases could be accurately evaluated using noninvasive CTP. When combined with preoperative embolization, this approach effectively and safely reduced intraoperative blood loss in the setting of separation surgery.

Pre-operative spine tumour embolization: Clinical outcomes and effect of embolization completeness

INTRODUCTION

To assess the association between the impact of the completeness of pre-operative spine tumour embolisation and clinical outcomes, including estimated blood loss (EBL), neurological status and complications.

METHODS

Retrospective chart review of all preoperative spine tumour embolisation procedures performed over 11 years by a single operator (2007-2018) at Vancouver General Hospital on 44 consecutive patients (mean age 57; 77% males) with 46 embolisation procedures, of which surgery was done en bloc in 26 cases and intralesional in the remaining 20. A multivariable negative binomial regression model was fit to examine the association between EBL and surgery type, tumour characteristics, embolisation completeness and operative duration.

RESULTS

Among intralesional surgeries, complete versus incomplete embolisation was associated with reduced blood loss (772 vs 1428 mL, P < 0.01). There was no statistically significant difference in neurological outcomes or complications between groups. Highly vascular tumours correlated with greater blood loss than their less vascular counterparts, but tumour location did not have a statistically significant effect.

CONCLUSION

This study provides evidence in support of our hypothesis that complete as opposed to incomplete tumour embolisation correlates with reduced blood loss in intralesional surgeries. Randomised control trials with larger samples are necessary to confirm this benefit and to ascertain other potential clinical benefits.

Refinement of nBCA embolization technique in treatment of metastatic spinal tumors: Case series and technical report

BACKGROUND AND OBJECTIVES

Preoperative embolization of metastatic spinal tumors (MSTs) has proven advantageous in limiting intraoperative blood loss (IBL) during resection. N-butyl cyanoacrylate (nBCA) is a liquid embolic agent known for its rapid hemostatic effects. However, nBCA is associated with a higher risk of distal nontarget embolization. This study highlights the refinement of the embolization technique and assesses its efficacy in performing an initial distal segmental artery plug with concentrated nBCA followed by proximal diluted nBCA for MSTs.

METHODS

A retrospective review of patients with MST (2018-2023) was performed. Patients who underwent preoperative nBCA endovascular embolization prior to tumor resection and spinal instrumentation were included. Baseline standard spinal angiography was performed.

RESULTS

Sixteen patients (13 men, 3 women; 56.0 ± 12.4 years) met inclusion criteria. And 43.75% (7 of 16) had thoracic levels, 37.5% (6 of 16) lumbar, and 18.75% (3 of 16) sacral. The most common primary tumor was renal cell carcinoma (43.75%, 7 of 16). A total of 43 pedicles were embolized (median 3), resulting in complete/near complete obliteration of the tumor blush. Most pedicles (83.7%, 36 of 43) received a single dilute concentration of nBCA; however, 16.3% (7 of 43) received two separate concentrations of nBCA, a denser concentration distally into the segmental artery and a diluted concentration proximally into the tumor bed. Mean IBL was 1150 ± 1201 mL in 3 distal plug patients distal plug patients versus 1625 ± 681 mL in 12 other patients. There were no complications related to embolization.

CONCLUSION

Performing a distal, concentrated nBCA plug during preoperative nBCA embolization of MSTs may increase tumor penetration and reduce IBL.

Efficacy of Subtraction Computed Tomography Arteriography During Preoperative Embolization in Spinal Tumors

Background

This study aimed to evaluate the efficacy of subtraction computed tomography arteriography (s-CTA) during preoperative embolization in spinal tumors.

Methods

The study analyzed 17 vertebrae in 13 patients who underwent preoperative embolization before spinal fixation surgery for malignant spinal tumors to decrease blood loss at our hospital from 2019 to 2021. Their ages ranged from 56 to 88 years (average, 73.5 years). Metastatic bone tumors were most common, including five cases originating as lung carcinomas and three as renal cancers. After digital subtraction angiography of selected tumor-feeding arteries and non-subtraction CTA (ns-CTA) were performed, s-CTA was conducted using data obtained from both procedures. A clarity score of the boundary between the normal bone and tumor was derived for each patient, which was then classified into four grades (good, 3 points; fair, 2 points; faint, 1 point; poor, 0 points) by two experienced radiologists, followed by a comparison between the s-CTA and ns-CTA groups using the Wilcoxon signed-rank test.

Results

Clarity scores were significantly higher in the s-CTA group than in the ns-CTA group (P < 0.001). The agreement of Cohen's coefficients between the two radiologists was κ = 0.724 in s-CTA scoring and κ = 0.622 in ns-CTA scoring, which were moderately matched. Seven arteries were not embolized due to insufficient tumor contrast enhancement and their poor relation to the surgical invasion zone. No complications were observed during or after embolization.

Conclusion

S-CTA successfully distinguished between tumor and normal bone and may help avoid unnecessary embolization.

Percutaneous n-butyl cyanoacrylate embolization of cervical metastatic disease via an anterolateral approach

Symptomatic vascular spinal metastases will benefit from pre-operative tumor embolization - percutaneous with or without adjunct endovascular embolization. However, when a transpedicular approach is not feasible, an anterolateral approach may be a viable alternative. The authors report a 57-year-old woman with prior C3-T1 instrumentation who presented with acute cord compression from a pathologic C5 vertebral body fracture related to metastatic renal cell carcinoma. The patient underwent CT-guided direct tumor embolization with 33% n-butyl-2-cyanoacrylate via an anterolateral approach, followed by C5-corpectomy and anterior cervical C4-C6 fusion and plating with minimal blood loss (est. 20 cc) and a stable neurological exam post-operatively. In patients with highly vascular cervical metastatic disease who lack a viable transpedicular approach for preoperative tumor embolization, a CT-guided anterolateral approach is a viable alternative.

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.

Current state of preoperative embolization for spinal metastasis - A survey by the EANS spine section

Introduction

Preoperative embolization (PE) for spinal metastasis can be used to reduce tumor blood supply in selected patients. The decision whether and when to perform PE varies largely among spine surgeons and centers.

Research question

The aim was to understand the current decision-making process in European spine centers.

Material and methods

The European Association of Neurosurgical Societies (EANS) spine section designed a 13-item online survey. It was distributed to neurosurgical residents and board-certified neurosurgeons between 7th of February and May 5, 2023.

Results

We analyzed 120 survey responses. Most participants were board-certified neurosurgeons (71%) or residents (26%) in university hospitals (76%). Routinely performed PE was stated not a common practice in 62%. Of those using PE, 25% indicated to perform it in selected cases requiring vertebral body replacement. Reasons for not performing PE included lack of time (44%), unclear benefits (25%), no significant bleeding without PE (19%), and significant bleeding despite PE (8%). Most participants opted for PE < 24h before surgery, but in a separate anesthesia (54%). More experienced participants were more likely to observe reduced blood loss (BL) after PE (p = 0.014). The most common reported complications were neurological deterioration due to spinal cord infarction (n = 15) and swelling due to tumor necrosis (n = 13).

Discussion and conclusions

PE is still not a routine among European spine surgeons and is considered mostly for elective cases with hypervascularized tumors scheduled in a separate anesthesia <24h before tumor resection. Most participants noted reduced intraoperative BL, but also a risk of procedure-related complications.

Predictive factors for respiratory failure and in-hospital mortality after surgery for spinal metastasis

PURPOSE

Spinal metastasis surgeries carry substantial risk of complications. PRF is among complications that significantly increase mortality rate and length of hospital stay. The risk factor of PRF after spinal metastasis surgery has not been investigated. This study aims to identify the predictors of postoperative respiratory failure (PRF) and in-hospital death after spinal metastasis surgery.

METHODS

We retrospectively reviewed consecutive patients with spinal metastasis surgically treated between 2008 and 2018. PRF was defined as mechanical ventilator dependence > 48 h postoperatively (MVD) or unplanned postoperative intubation (UPI). Collected data include demographics, laboratory data, radiographic and operative data, and postoperative complications. Stepwise logistic regression analysis was used to determine predictors independently associated with PRFs and in-hospital death.

RESULTS

This study included 236 patients (average age 57 ± 14 years, 126 males). MVD and UPI occurred in 13 (5.5%) patients and 13 (5.5%) patients, respectively. During admission, 14 (5.9%) patients had died postoperatively. Multivariate logistic regression analysis revealed significant predictors of MVD included intraoperative blood loss > 2000 mL (odds ratio [OR] 12.28, 95% confidence interval [CI] 2.88-52.36), surgery involving cervical spine (OR 9.58, 95% CI 1.94-47.25), and ASA classification ≥ 4 (OR 6.59, 95% CI 1.85-23.42). The predictive factors of UPI included postoperative sepsis (OR 20.48, 95% CI 3.47-120.86), central nervous system (CNS) metastasis (OR 10.21, 95% CI 1.42-73.18), lung metastasis (OR 7.18, 95% CI 1.09-47.4), and postoperative pulmonary complications (OR 6.85, 95% CI 1.44-32.52). The predictive factors of in-hospital death included postoperative sepsis (OR 13.15, 95% CI 2.92-59.26), CNS metastasis (OR 10.55, 95% CI 1.54-72.05), and postoperative pulmonary complications (OR 9.87, 95% CI 2.35-41.45).

CONCLUSION

PRFs and in-hospital death are not uncommon after spinal metastasis surgery. Predictive factors for PRFs included preoperative comorbidities, intraoperative massive blood loss, and postoperative complications. Identification of risk factors may help guide therapeutic decision-making and patient counseling.

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

OBJECTIVES

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

KEY POINTS

• 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.

Competing risk nomogram for predicting prognosis of patients with spinal and pelvic chordoma: A SEER-based retrospective study

PURPOSE

Recently, competing risk nomograms were widely applied to predict prognosis in numerous tumors other than chordoma. Here, we aimed to construct and validate a competing-risk-based prognostic nomogram to predict 3- and 5-year cancer-specific death (CSD) in patients with spinal and pelvic chordoma.

METHODS

All chordoma patient data were abstracted from the Surveillance, Epidemiology, and End Results (SEER) resource, and a total of 485 chordoma patients were eventually included in this study. Multivariate competing risk model and multivariate Cox model were used to determine independent prognostic factors, respectively, and the results of the two models were compared. Nomogram was employed to visualize the competing risk model. The discrimination, calibration, and clinical utility of this model were evaluated by Harrell concordance index (C-index), time-dependent receiver operating characteristic (ROC) curves, calibration plots, and decision curve analysis (DCA). Ten-fold cross-validation was further utilized to validate the prognostic nomogram.

RESULTS

Significant prognostic factors affecting CSD were age (P = 0.016), localized involvement (P < 0.0001), and radical resection (P < 0.001) in the multivariate competing risk model. C-indexes were 0.799 and 0.76, and AUC were 0.812 and 0.778 for 3- and 5-year CSD. Calibration plots demonstrated the nomogram was well-fitted, and DCA indicated good clinical utility. The nomogram showed good performance in the 10-fold cross-validation.

CONCLUSION

We successfully built the first competing-risk-based nomogram to predict clinical outcomes in patients with spinal and pelvic chordoma. This well-established nomogram hopes to help clinicians with precise prognostic assessment and thus improve clinical outcomes.

Preoperative embolization in surgical treatment of spinal metastases originating from non-hypervascular primary tumors: a propensity score matched study using 495 patients

BACKGROUND CONTEXT

Preoperative embolization (PE) reduces intraoperative blood loss during surgery for spinal metastases of hypervascular primary tumors such as thyroid and renal cell tumors. However, most spinal metastases originate from primary breast, prostate, and lung tumors and it remains unclear whether these and other spinal metastases benefit from PE.

PURPOSE

To assess the (1) efficacy of PE on the amount of intraoperative blood loss and safety in patients with spinal metastases originating from non-hypervascular primary tumors, and (2) secondary outcomes including perioperative allogeneic blood transfusion, anesthesia time, hospitalization, postoperative complication within 30 days, reoperation, 90-day mortality, and 1-year mortality.

STUDY DESIGN

Retrospective propensity-score matched, case-control study at 2 academic tertiary medical centers.

PATIENT SAMPLE

Patients 18 years of age or older undergoing surgery for spinal metastases originating from primary non-thyroid, non-renal cell, and non-hepatocellular tumors between January 1, 2002 and December 31, 2016 were included.

OUTCOME MEASURES

The primary outcomes were estimated amount of intraoperative blood loss and complications attributable to PE, such as neurologic injury, wound infection, thrombosis, or dissection. The secondary outcomes included perioperative allogeneic blood transfusion, anesthesia time, hospitalization, postoperative complication within 30 days, reoperation, 90-day mortality, and 1-year mortality.

METHODS

In total, 495 patients were identified, of which 54 (11%) underwent PE. After propensity score matching on 21 variables, including primary tumor, number of spinal levels, and surgical treatment, 53 non-PE patients were matched to 53 PE patients. Matching was adequate measured by comparing the matched variables, testing the standardized mean differences (<0.25), and inspecting Kernel density plots. The degree of embolization was noted to be complete, until stasis, or successful in 43 (80%) patients.

RESULTS

Intraoperative blood loss did not differ between both groups with a median blood loss in liters of 0.6 (IQR, 0.4-1.2) for non-PE patients and 0.9 (IQR, 0.6-1.2) for PE patients (p=.32). No complications occurred during embolization or the time between embolization and surgery. No differences were found in terms of the secondary outcomes.

CONCLUSIONS

Our data suggest that, although no complications occurred and the embolization procedure can be considered safe, patients with non-hypervascular spinal metastases might not benefit from PE. A larger, prospective study could confirm or refute these study findings and aid in elucidating a subset of spinal metastases that might benefit from PE.

Does the anatomical region predict blood loss or neurological deficits in embolized renal cancer spine metastases? A single-center experience with 31 patients

Background

No comparison of a single hypervascular tumor entity in terms of major complications in different spinal regions has been performed. We aimed to evaluate post-embolic and post-operative outcomes in anatomic regions with renal cell carcinoma (RCC) metastases to the spine.

Methods

We retrospectively evaluated data from patients with confirmed, embolized, and surgically treated RCC spine metastases at a single-spine center between 2010 and 2020. Patients were divided into thoracic (TSM) and lumbar (LSM) spine metastasis groups.

Results

Seventeen patients had TSM and 14 had LSM. In all cases, embolization was performed preoperatively. The ΔHb value did not differ between the two groups pre- and postoperatively (p=0.3934). There was no significant difference in intraoperative blood loss between both groups either within 1 day or 2 days after embolization. Neurological deficits occurred in eight patients after embolization or surgery, with no significant difference between TSM (n=5) and LSM (n=3).

Conclusions

Embolization is the standard procedure for the preoperative treatment of hypervascular spinal metastases, possible up to 48 h before surgery, without the risk of higher intraoperative blood loss. Regardless of intraoperative complications, major complications can occur up to several hours after embolization. We recommend surgery the day after embolization to reliably detect neurologic complications from this procedure.

The Efficacy and Complications of Preoperative Embolization of Metastatic Spinal Tumors: Risk of Paralysis after Embolization

Introduction

This study investigated the efficacy and complications of preoperative embolization for spinal metastatic tumors, focusing on the etiology of post-embolization paralysis.

Methods

We retrospectively reviewed the data of 44 consecutive patients with spinal metastases treated between September 2012 and December 2020. Intraoperative blood loss and postoperative transfusion requirement were compared between the embolization (+) and (−) groups. Complications associated with embolization were reviewed.

Results

Overall, 30 patients (68%) underwent preoperative embolization. All the patients in both groups underwent palliative posterior decompression and fusion. The mean intraoperative blood loss in the overall population was 359 ml (range, minimum-2190 ml) and was 401 ml and 267 ml in the embolization (+) and embolization (−) groups, respectively. Four patients (9%) (2 patients from each group) required blood transfusion. There were no significant between-group differences in blood loss and blood transfusion requirements. All 7 patients with hypervascular tumors were in the embolization (+) group. Two patients experienced muscle weakness in the lower extremities on days 1 and 3 after embolization. There were metastases in T5 and T1-2, and magnetic resonance imaging after embolization showed slight exacerbation of spinal cord compression. The patients showed partial recovery after surgery.

Conclusions

With the predominance of hypervascular tumors in the embolization (+) group, preoperative embolization may positively affect intraoperative bleeding. Embolization of metastatic spinal tumors may pose a risk of paralysis. Although the cause of paralysis remains unclear, it might be due to the aggravation of spinal cord compression. Considering this risk of paralysis, we advocate performing surgery as soon as possible after embolization.

Preoperative embolization of hypervascular spinal tumors: Two case reports

The performance of preoperative embolization on a spinal tumor can be a useful adjunctive procedure that minimizes blood loss and complications, particularly for both metastatic and non-metastatic hypervascular tumors. We discuss two cases of hypervascular spinal tumors that were successfully treated with preoperative embolization and surgery. The first patient was an 18-year-old man who presented with cervical and shoulder pain for two months without paralysis or weakness. Magnetic resonance imaging revealed a tumor located in the D2 posterior vertebral arch that extended into the spinal canal and compressed the spinal cord. The second patient was a 68-year-old man with back pain that radiated to the legs for ten days. Magnetic resonance imaging revealed a mass in the L4 vertebral body. Both patients received tumor embolization and surgery. After surgery, neither patient experienced any major complications. Histological examination revealed osteoblastoma in the first patient and plasmacytoma in the second patient.

Transradial Approach for Thoracolumbar Spinal Angiography and Tumor Embolization: Feasibility and Technical Considerations

The transradial approach (TRA) is an effective and safe alternative to transfemoral access for diagnostic neuroangiography and craniocervical interventions. While the technical aspects of supraclavicular intervention are well-described, there are little data on the TRA for thoracolumbar angiography and intervention. The authors describe the feasibility of the TRA for preoperative thoracic tumor embolization, emphasizing technique, device selection, navigation, and catheterization of thoracolumbar segmental arteries. This approach extends the benefits of TRA to spinal interventional neuroradiology.

Clinical-Deep Neural Network and Clinical-Radiomics Nomograms for Predicting the Intraoperative Massive Blood Loss of Pelvic and Sacral Tumors

Background

Patients with pelvic and sacral tumors are prone to massive blood loss (MBL) during surgery, which may endanger their lives.

Purposes

This study aimed to determine the feasibility of using deep neural network (DNN) and radiomics nomogram (RN) based on 3D computed tomography (CT) features and clinical characteristics to predict the intraoperative MBL of pelvic and sacral tumors.

Materials and Methods

This single-center retrospective analysis included 810 patients with pelvic and sacral tumors. 1316 CT and CT enhanced radiomics features were extracted. RN1 and RN2 were constructed by random grouping and time node grouping, respectively. The DNN models were constructed for comparison with RN. Clinical factors associated with the MBL were also evaluated. The area under the receiver operating characteristic curve (AUC) and accuracy (ACC) were used to evaluate different models.

Results

Radscore, tumor type, tumor location, and sex were significant predictors of the MBL of pelvic and sacral tumors (P < 0.05), of which radscore (OR, ranging from 2.109 to 4.706, P < 0.001) was the most important. The clinical-DNN and clinical-RN performed better than DNN and RN. The best-performing clinical-DNN model based on CT features exhibited an AUC of 0.92 and an ACC of 0.97 in the training set, and an AUC of 0.92 and an ACC of 0.75 in the validation set.

Conclusions

The clinical-DNN and clinical-RN had good performance in predicting the MBL of pelvic and sacral tumors, which could be used for clinical decision-making.

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.

Musculoskeletal Interventional Radiology in the Pediatric Population: State of the Art

Interventional radiology procedures have been proven to be as effective as traditional surgery but usually are characterized by lower morbidity rates. In this article, the most diffuse IR treatments for pediatric lesions are reviewed with the aim of describing main advantages and drawbacks. Ablation procedures (in particular RFA and MRgFUS) are widely used for the management of osteoid osteoma and osteoblastoma whereas intracystic injection of methylprednisolone acetate is performed for simple bone cysts. Sclerosing agents and where possible, selective arterial embolization are used for treatment of aneurysmal bone cysts and other vascular malformations. In the management of malignant muscoloskeletal tumors, the role interventional radiology is mainly represented by percutaneous biopsies, and by adiuvant selective embolizations in presence of hypervascular lesions to be submitted to surgery.

Intraoperative blood loss in oncological spine surgery

OBJECTIVE

Intraoperative blood loss in patients undergoing oncological spine surgery poses a major challenge for vulnerable patients. The goal of this study was to assess how the surgical procedure, tumor type, and tumor anatomy, as well as anesthesiological parameters, affect intraoperative blood loss in oncological spine surgery and to use this information to generate a short preoperative checklist for spine surgeons and anesthesiologists to identify patients at risk for increased intraoperative blood loss.

METHODS

The authors performed a retrospective analysis of 430 oncological patients who underwent spine surgery between 2013 and 2018 at the university medical spine center. Enrolled patients had metastatic tumor of the spine requiring surgical decompression of neural structures and/or stabilization including tumor biopsy using an open, percutaneous, and/or combined dorsoventral approach. Patients requiring vertebro- and kyphoplasty or biopsy only were excluded. Statistical analyses performed included a multiple linear regression analysis.

RESULTS

The mean intraoperative blood loss in the study patient cohort was 1176 ± 1209 ml. In total, 33.8% of patients received intraoperative red blood cell transfusions. The statistical analyses showed that tumor histology indicating myeloma, operative procedure length, epidural spinal cord compression (ESCC) score, tumor localization, BMI, and surgical strategy were significantly associated with increased intraoperative blood loss or risk of needing allogeneic blood transfusions. Anesthesiological parameters such as the American Society of Anesthesiologists (ASA) Physical Status classification score were not associated with blood loss. Multiple linear regression analysis demonstrated good predictive value (r = 0.437) for a five-item preoperative checklist to identify patients at risk for high intraoperative blood loss.

CONCLUSIONS

The analyses performed in this study demonstrated key factors affecting intraoperative blood loss and showed that a simple preoperative checklist including these factors can be used to identify patients undergoing surgery for metastatic spine tumors who are at risk for increased intraoperative blood loss.

ABBREVIATIONS

ABT = allogeneic blood transfusion; ASA = American Society of Anesthesiologists; ESCC = epidural spinal cord compression; KW = Kruskal-Wallis; MET = metabolic equivalent of task; RBC = red blood cell.

Trends in Utilization of Preoperative Embolization for Spinal Metastases: A Study of the National Inpatient Sample 2005-2017

Purpose

While previous studies have suggested that preoperative embolization of hypervascular spinal metastases may alleviate intraoperative blood loss and improve resectability, trends and driving factors for choosing this approach have not been extensively explored. Therefore, we evaluated the trends and assessed the factors associated with preoperative embolization utilization for spinal metastatic tumors using a national inpatient database.

Materials and Methods

The National Inpatient Sample database of the Healthcare Cost and Utilization Project was queried for patients undergoing surgical resection for spinal metastasis between January 1, 2005 and December 31, 2017. Patients undergoing preoperative embolization were identified; trends in the utilization of preoperative embolization were analyzed using the Cochran-Armitage test. Multivariable regression was conducted to assess factors associated with higher preoperative embolization utilization.

Results

A total of 11,508 patients with spinal metastasis were identified; 105 (0.91%) underwent preoperative embolization. Of those 105 patients, 79 (75.24%) patients had a primary renal cancer, as compared to 1,732 (15.19%) of those who did not undergo preoperative embolization (P<0.001). The majority of patients in the non-preoperative embolization cohort had a primary lung tumor (n=3,562, 31.24%). Additionally, patient comorbidities were similar among the 2 groups (P>0.05). Trends in preoperative embolization indicated an increase of 0.16% (standard error: 0.024%, P<0.001) in utilization per year.

Conclusion

Utilization of preoperative embolization for spinal metastasis is increasing yearly, especially for patients with renal cancer, suggesting that surgeons may increasingly consider embolization before surgical resection for hypervascular tumors. Additionally, the literature has shown the intraoperative and postoperative benefits of this procedure.

Reliability and accuracy of time-resolved contrast-enhanced magnetic resonance angiography in hypervascular spinal metastases prior embolization

OBJECTIVES

Preoperative embolization of hypervascular spinal metastases (HSM) is efficient to reduce perioperative bleeding. However, intra-arterial digital subtraction angiography (IA-DSA) must confirm the hypervascular nature and rule out spinal cord arterial feeders. This study aimed to evaluate the reliability and accuracy of time-resolved contrast-enhanced magnetic resonance angiography (TR-CE-MRA) in assessing HSM prior to embolization.

METHODS

All consecutive patients referred for preoperative embolization of an HSM were prospectively included. TR-CE-MRA sequences and selective IA-DSA were performed prior to embolization. Two readers independently reviewed imaging data to grade tumor vascularity (using a 3-grade and a dichotomized "yes vs no" scale) and identify the arterial supply of the spinal cord. Interobserver and intermodality agreements were estimated using kappa statistics.

RESULTS

Thirty patients included between 2016 and 2019 were assessed for 55 levels. Interobserver agreement was moderate (κ = 0.52; 95% CI [0.09-0.81]) for TR-CE-MRA. Intermodality agreement between TR-CE-MRA and IA-DSA was good (κ = 0.74; 95% CI [0.37-1.00]). TR-CE-MRA had a sensitivity of 97.9%, a specificity of 71.4%, a positive predictive value of 95.9%, a negative predictive value of 83.3%, and an overall accuracy of 94.6%, for differentiating hypervascular from non-hypervascular SM. The arterial supply of the spine was assessable in 2/30 (6.7%) cases with no interobserver agreement (κ < 0).

CONCLUSIONS

TR-CE-MRA can reliably differentiate hypervascular from non-hypervascular SM and thereby avoid futile IA-DSAs. However, TR-CE-MRA was not able to evaluate the vascular supply of the spinal cord at the target levels, thus limiting its scope as a pretherapeutic assessment tool.

KEY POINTS

• TR-CE-MRA aids in distinguishing hypervascular from non-hypervascular spinal metastases. • TR-CE-MRA could avoid one-quarter of patients referred for HSM embolization to undergo futile conventional angiography. • TR-CE-MRA's spatial resolution is insufficient to replace IA-DSA in the pretherapeutic assessment of the spinal cord vascular anatomy.

Surgical Treatment of Intramedullary Hemangioblastomas: Current State of Problem (Review)

Intramedullary hemangioblastomas (HAB) refer to very rare highly vascularized vascular spinal cord tumors associated with various neurological disorders. Effective HAB therapy to a greater extent depends on diagnostic accuracy and the absence of intra- and postoperative complications.

The present study is a review of publications concerned with modern diagnostic and therapeutic techniques to control spinal HAB. The authors showed that perfusion computed tomography, computed tomographic angiography, and magnetic resonance angiography can be reasonably used for diagnosis and differentiation in a number of HAB due to their high vascularization. Preoperative embolization significantly reducing intraoperative bleeding risks is highly efficient. Some authors recommend this procedure in case of large lesions and high risks of intraoperative bleeding. The review also considered intraoperative imaging of a tumor and its feeding vessels using indocyanine green providing inspectability over the total tumor resection and clear imaging of tumor vascular architecture. The advantages and restrictions of the mentioned procedures were described.

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.

Pre-Operative Embolisation of Musculoskeletal Tumours - A Single Centre Experience

Introduction

The management of musculoskeletal tumours is complex and requires a multi-disciplinary approach. Preoperative embolisation can be often employed to reduce intra-operative blood loss and complication rates from surgery. We report our experience with the safety, technical success and efficacy of pre-operative embolisation in musculoskeletal tumours.

Materials and Methods

Thirteen consecutive patients who underwent pre-operative embolisation of a musculoskeletal tumour followed by surgical intervention at our institution from May 2012 to January 2016 were enrolled into the study. Patient demographics, tumour characteristics, embolisation techniques and type of surgery were recorded. Technical success of embolisation, amount of blood loss during surgery and transfusion requirements were estimated.

Results

There were five female and eight male patients who underwent pre-operative embolisation during the study period. The age ranged between 16 to 68 years, and the median age was 54. Technical success was achieved in all patients. Mean intra-operative blood loss was 1403ml, with a range of 150ml to 6900ml. Eight patients (62%) required intra-operative blood products of packed red blood cells and fresh frozen plasma. No major complications occurred during embolisation.

Conclusion

Pre-operative trans-arterial embolisation is feasible and safe for a variety of large and hypervascular musculoskeletal tumours. Our small series suggests that preoperative embolisation could contribute to the reduction of the intra-operative and post-operative blood product transfusion. It should be considered as a pre-operative adjunct for major tumour resections with a high risk of bleeding. The use of the haemoglobin gap complemented the assessment of perioperative blood loss.

Percutaneous embolization of sporadic lumbar nerve root haemangioblastoma under local anaesthesia

Pre-operative embolization of spinal tumours are mainly performed using a transarterial approach. Percutaneous embolization of spinal tumours are undertaken much less frequently, though its use has been reported in hypervascular spinal metastases^1,2 and spinal paraganglioma.³ We present a patient in whom pre-operative percutaneous embolization has been performed to a recurrent lumbar nerve root haemangioblastoma that had previously been embolized using a transarterial approach. Percutaneous embolization, through targeted percutaneous puncture of the extradural component, helped reduce intraoperative blood loss, and minimize risk of spinal ischaemia.

Effects of surgery and radiofrequency ablation in the treatment of spinal metastases and analysis of the influencing factors of prognosis

Effects of surgery and radiofrequency ablation in the treatment of spinal metastases were explored to analyze the influencing factors of prognosis. A total of 132 patients with spinal metastases admitted to Weifang People's Hospital were selected, 67 patients who underwent simple surgery were selected as the control group, and 65 patients who underwent radiofrequency ablation assisted surgery were the research group. The time of operation and intraoperative blood loss of patients in the two groups were recorded and compared. The visual analogue pain score (VAS), Karnofsky (KPS) score, Frankel spinal cord injury grading, and complications within 6 months after surgery were compared. The patients were followed up for 36 months and the survival rates were analyzed. Cox regression model was used to analyze the factors affecting the prognosis of patients. The time of operation and blood loss in the research group was significantly lower than that in the control group (P<0.05). The VAS, KPS scores, and Frankel grading of patients in the two groups after treatment were significantly improved compared with those before treatment, but the VAS and KPS scores of patients in the research group were significantly improved compared with those in the control group (P<0.05). The incidence rate of complications and 3-year recurrence rate in the research group were lower than those in the control group, and the 3-year survival rate was significantly higher than that in the control group (P<0.05). The number of pathological cones, visceral metastasis, malignant degree, and radiofrequency ablation therapy are independent risk factors for poor prognosis of patients. Radiofrequency ablation assisted surgery can effectively improve the clinical efficacy of patients with spinal metastases, reduce postoperative complications and recurrence rate of patients, and prolong the survival time of patients compared with simple surgical treatment. It is worthy of clinical application.

Effect of combined treatment including surgery and postoperative adjuvant therapy on spinal metastases of Tomita type 7

OBJECTIVES

Identify the efficacy of multidisciplinary treatment including palliative spinal surgery on patients with Tomita type 7 spinal metastases.

PATIENTS AND METHODS

A retrospective analysis of surgery treated spinal metastatic patients from January 2013 to December 2016 in Tianjin Medical University Cancer Institute and Hospital were performed. Surgical procedures and intraoperative parameters and postoperative adjuvent treatments were studied. Patients' demographic characteristics and medical conditions including paralysis statues, quality of life and pain levels and postoperative survival time were identified.

RESULTS

50 patients were identified with mean age at the time of surgery of 57.68 years old (range 27-78 years). The mean Tokuhashi score was 8.48 and the spinal instability neoplastic score (SINS) averaged at 10.52 points. 48 patients (96%) encountered epidural spinal cord compression. Kaplan-Meier method determined median postoperative survival time was 12.00 months (95% CI: 7.05-16.95 months). The mean score of visual analogue scale (VAS) decreased from 7.66 preoperatively to 1.96 postoperatively. The Frankel scale was improved by at least one grade in 47 patients. Patient's quality of life showed significant improvements.

CONCLUSION

Multidisciplinary treatment including palliative spinal surgery was associated with alleviating pain, improving neurologic function and quality of life in patients with Tomita type 7 spinal metastases.

The Impact of Metastatic Spinal Tumor Location on 30-Day Perioperative Mortality and Morbidity After Surgical Decompression

STUDY DESIGN

A retrospective cohort study from 2011 to 2014 was performed using the American College of Surgeons National Surgical Quality Improvement Program database.

OBJECTIVE

The purpose of this study was to assess the impact of tumor location in the cervical, thoracic, or lumbosacral spine on 30-day perioperative mortality and morbidity after surgical decompression of metastatic extradural spinal tumors.

SUMMARY OF BACKGROUND DATA

Operative treatment of metastatic spinal tumors involves extensive procedures that are associated with significant complication rates and healthcare costs. Past studies have examined various risk factors for poor clinical outcomes after surgical decompression procedures for spinal tumors, but few studies have specifically investigated the impact of tumor location on perioperative mortality and morbidity.

METHODS

We identified 2238 patients in the American College of Surgeons National Surgical Quality Improvement Program database who underwent laminectomy for excision of metastatic extradural tumors in the cervical, thoracic, or lumbosacral spine. Baseline patient characteristics were collected from the database. Univariate and multivariate regression analyses were performed to examine the association between spinal tumor location and 30-day perioperative mortality and morbidity.

RESULTS

On univariate analysis, cervical spinal tumors were associated with the highest rate of pulmonary complications. Multivariate regression analysis demonstrated that cervical spinal tumors had the highest odds of multiple perioperative complications. However, thoracic spinal tumors were associated with the highest risk of intra- or postoperative blood transfusion. In contrast, patients with metastatic tumors in the lumbosacral spine had lower odds of perioperative mortality, pulmonary complications, and sepsis.

CONCLUSION

Tumor location is an independent risk factor for perioperative mortality and morbidity after surgical decompression of metastatic spinal tumors. The addition of tumor location to existing prognostic scoring systems may help to improve their predictive accuracy.

LEVEL OF EVIDENCE

3.

Angiography Before Posterior Mediastinal Tumor Resection: Selection Criteria and Patient Outcomes

BACKGROUND

Resection of posterior mediastinal tumors may be complicated by bleeding or neurologic injury. Preoperative spinal angiography of mediastinal tumors has been underreported or not commonly practiced. This study evaluated the selection criteria and outcomes of patients with posterior mediastinal tumors who underwent preoperative angiography and embolization.

METHODS

This was a single-institution retrospective study of patients with posterior mediastinal tumors from 2002 to 2016. Multilevel spinal angiography was performed, with or without selective arterial embolization of vascular supply, in patients selected by thoracic or neurologic surgeons.

RESULTS

Ten of 87 patients (11%) with posterior mediastinal tumors underwent preoperative angiography. A mean of 11 arteries (range, 2 to 25) were studied. Embolization in 7 of 10 patients successfully occluded 1 to 3 arteries. There was no significant difference in age, sex, body mass index, American Society of Anesthesiologists Physical Status Classification, operative time, operative blood loss, complications, or death between patients with or without angiography. Patients who underwent angiography had larger tumors (1,490 vs 97 cm³, p < 0.0001), involvement of the neuroforamen (44% vs 10%, p < 0.05), and a longer hospital stay (9 vs 4.5 days, p < 0.05). Angiography was complicated in 1 patient by vocal cord ulceration after intubation of a tumor-compressed trachea. Shared blood supply between the tumor and the spinal cord precluded embolization and tumor resection in 1 patient. Use of angiography increased over time.

CONCLUSIONS

Selective preoperative angiography for evaluation of posterior mediastinal tumors identifies arterial variations, threatened spinal arteries, and targets for embolization. The specific role of angiography and embolization requires further investigation to standardize indications and protocols for the number of arteries examined.

Spinal cord hemangioblastomas: significance of intraoperative neurophysiological monitoring for resection and long-term outcome

OBJECTIVE

Spinal cord hemangioblastomas are rare benign tumors developing either sporadically or as part of von Hippel-Lindau (VHL) disease. Generally, resection is the treatment of choice. However, the significance of intraoperative neurophysiological monitoring (IONM) for resection and postoperative outcome is still controversial. The authors analyzed the surgical and clinical courses of patients who had undergone resection of spinal cord hemangioblastoma, with special attention to preoperative imaging, the use of IONM, and short- and long-term outcomes.

METHODS

A series of 24 patients (male/female 1:1, lesion sporadic/associated with VHL 2.4:1) who had undergone 26 operations for the resection of 27 spinal cord hemangioblastomas was analyzed. All patients had undergone pre- and postoperative contrast-enhanced MRI. In all cases, microsurgical tumor removal had been performed under continuous IONM of both somatosensory and transcranial motor evoked potentials as well as electromyographic recording. Clinical characteristics, imaging findings, and operative records were retrospectively analyzed. Outcome parameters included short- and long-term status as regards sensorimotor deficits and a questionnaire on general performance, patient satisfaction, and Oswestry Disability Index (ODI) at the end of the follow-up period. The impact of IONM findings on postoperative deficits and outcome parameters as well as risk factors affecting functional prognosis was statistically assessed.

RESULTS

Preoperative symptoms (mean duration 16.2 ± 22.0 months) included sensory changes (100.0%), pain (66.7%), spinal ataxia (66.7%), motor deficit (41.7%), and bladder/bowel dysfunction (12.5%). Average age at the first operation was 36.8 ± 12.8 years. Most tumors (21 intramedullary, 6 intra- and/or extramedullary) were located dorsally (92.6%) and cervically (77.8%) and were accompanied by peritumoral edema and/or syringomyelia (81.5%). Tumor resection was achieved via laminectomy for 15 tumors, hemilaminectomy for 5, laminoplasty for 6, and interlaminar approach for 1. Gross-total resection was accomplished for 26 tumors (96.3%) with no local tumor recurrence during follow-up. Intraoperative neurophysiological monitoring was nonpathological in 11 operations (42.3%) and pathological in 15 (57.7%). Patients with nonpathological IONM had significantly fewer new sensorimotor deficits (p = 0.005). Long-term follow-up evaluation (mean 7.9 ± 4.0 years postoperatively, 7 patients lost to follow-up) revealed a stable or improved McCormick myelopathy grade in 88.2% of the patients, and 88.2% reported a stable or improved overall outcome according to Odom's criteria. Long-term general performance was excellent with 88.2% having a WHO/Eastern Cooperative Oncology Group (ECOG) Performance Status grade ≤ 1, 76.5% a Karnofsky Performance Scale score ≥ 80, and 70.6% a Barthel Index (BI) of 100. The mean ODI (11.4% ± 12.5%) indicated only minimal disability. There was a significant correlation between pathological IONM findings and a worse long-term status according to the BI and ODI (p = 0.011 and 0.024, respectively). Additionally, VHL disease was a risk factor affecting functional prognosis (p = 0.044).

CONCLUSIONS

Microsurgical removal of spinal cord hemangioblastomas with IONM facilitates a satisfying long-term outcome for patients. Nonpathological IONM findings are associated with a lower risk of new sensorimotor deficits and correlate with a better overall long-term outcome. von Hippel–Lindau disease is a risk factor for a worse long-term prognosis.

Preoperative embolization in patients with metastatic spinal cord compression: mandatory or optional?

Background

The contribution of preoperative embolization in reducing intraoperative blood loss and its clinical importance are unclear. So, we aimed to compare the perioperative clinical outcomes based on whether preoperative embolization was performed and assess the role and safety of preoperative embolization in metastatic spinal cord compression (MSCC) patients.

Methods

We enrolled 52 patients (men, 37; women, 15) who underwent palliative decompression for MSCC. Demographic data, neurologic status, surgery-related data (operation time, estimated blood loss, and transfusion), complications, and survival time were recorded. Patients were categorized based on whether they received preoperative embolization: groups E (embolization) (n = 18) and NE (non-embolization) (n = 34) and the clinical parameters were compared. Subgroup analysis was performed specifically for cases of hypervascular tumors (23/52, 44%).

Results

The transfusion degree was greater in the NE group (4.6 pints) than in the E group (2.5 pints, P = 0.025); the other parameters did not differ between the groups. However, massive bleeding (>2000 mL) was more frequent in the NE group (10/34) than in the E group (0/18, P = 0.010). Subgroup analysis indicated that intraoperative blood loss was greater in the NE group (1988 mL) than in the E group (1095 mL, P = 0.042) in hypervascular tumor patients. Although massive bleeding was more frequent among hypervascular tumor patients, 3 patients with non-hypervascularized tumors also exhibited massive bleeding (P = 0.087).

Conclusions

Intraoperative blood loss and perioperative transfusion can be reduced by preoperative embolization in MSCC patients. Neurologic recovery, operation time, and complications did not differ according to the application of embolization. As preoperative embolization is relatively safe and effective for controlling intraoperative bleeding without any neurologic deterioration, it is highly recommended for hypervascular tumors. Moreover, it may also be effective for non-hypervascular tumors as massive bleeding may be noted in some cases.