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

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.

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.

Risk factors of total blood loss in the posterior surgery for patients with thoracolumbar metastasis

Background

Blood loss in posterior surgery patients with thoracolumbar metastasis posed a significant challenge to surgeons. This study aimed to explore the risk factors of blood loss in posterior surgery for patients with thoracolumbar metastasis.

Methods

One hundred forty-two patients were retrospectively reviewed. Their baseline characteristics were recorded. The Gross equation was used to calculate blood loss on a surgical day. Multivariate linear regression was used to analyze the risk factors.

Results

Mean blood loss of 142 patients were 2055 ± 94 ml. Hypervascular primary tumor (kidney, thyroid and liver) (P = 0.017), wide or marginal excision (en-bloc: P = 0.001), metastasis at the lumbar spine (P = 0.033), and the presence of extraosseous tumor mass (P = 0.012) were independent risk factors of blood loss in the posterior surgery. Sub-analysis showed that wide or marginal excision (en-bloc: P < 0.001) and metastasis at lumbar spine (P = 0.007) were associated with blood loss for patients with non-hyper vascular primary tumors. Wide or marginal excision (piece-meal: P = 0.014) and the presence of an extraosseous tumor mass (P = 0.034) were associated with blood loss for patients with hypervascular primary tumors.

Conclusion

Hypervascular primary tumor (kidney, thyroid, and liver) was an independent risk factor of blood loss in the posterior surgery. The presence of extraosseous tumor mass and wide or marginal excision (piece-meal) were independent risk factors for patients with hypervascular primary tumors. Metastasis at the lumbar spine and wide or marginal excision (en-bloc) were independent risk factors for patients with non-hyper vascular primary tumors.