Association of CT-DSA vascular assessment and perioperative outcomes in metastatic spinal surgery

Introduction: Computed tomography-digital subtraction angiography (CT-DSA) is a radiological method for assessing spinal metastatic tumor vascularity. The study aimed to investigate the association between CT-DSA results and perioperative outcomes in spinal metastatic surgery.

Material and methods: Patients who underwent spinal metastatic operations with preoperative CT-DSA examinations at any time between January 2018 to December 2022. CT-DSA was classified into five grades ranging from grade 0 to grade 4. Grades 3 and 4 were indicative of hypervascularity. We analyzed the perioperative outcomes of intraoperative blood loss amount, massive hemorrhage (≥2500 ml) occurrence, blood transfusion status, operation time, hospital stay duration, and 30-day and 60-day mortality rates. Logistic regression analyses were conducted to identify factors affecting the likelihood of massive hemorrhage in conjunction with CT-DSA.

Results: Data from 212 operations involving 209 patients were analyzed. In total, 30, 36, 66, 56, and 24 operations had CT-DSA grades from grade 0 to grade 4, respectively. Eighty (38 %) studies were indicative of hypervascularity. CT-DSA grade was positively correlated with the amount of operative blood loss, the occurrence of massive hemorrhage, and the amount of blood in blood transfusion (p < 0.05). However, CT-DSA grades was not significantly associated with operation duration or mortality rate. A multivariable analysis indicated that factors such as hemoglobulin, hypervascular pathology, and spinal instability neoplastic scores were positively correlated with CT-DSA grade. CT-DSA grade (odds ratio: 2.37, p = 0.02), spinal metastatic invasiveness index, and tumor size (≥50 mL) were found to be independent predictors in a multivariable logistic regression analysis where factors associated with massive hemorrhage were included. Hypervascular pathology type was not significantly associated with the likelihood of hemorrhage in the univariable and multivariable analyses.

Conclusions: CT-DSA serves as an effective tool for assessing vascularity, and is associated with intra-operative blood loss and likelihood of experiencing massive hemorrhage. The predictive capability of CT-DSA surpasses that of traditional histopathology classifications, making it a useful method for preoperative planning in spinal metastatic surgeries.