Preoperative Embolization in Spinal Tumour Surgery

Abstract

IntroductionPreoperative embolization has been shown to be effective in reducing intraoperative blood loss during metastatic spinal tumor surgery. However, the majority of studies investigating preoperative embolization for spinal metastases have preferentially selectedsecondaries fromrenal and thyroid as these are highly vascularized tumors. There is paucity of literature describing utility of embolization in other tumors. We aimed to determine the effect of preoperative embolization on intraoperative blood loss indifferent spinal tumors by type of surgical approaches. Materials and MethodsWe retrospectively evaluated 221 patients undergoing surgery for primary or metastatic spine tumors. Patients were analyzed for the effect of embolization agents, extent, level of embolization and timing between embolization & surgery, on estimated blood loss. Estimated blood loss and transfusion requirements were compared between embolized and non-embolized cases for different types of spinal tumor (metastatic lung, breast, renal, hepatocellular, thyroid, other epithelial tumors, myeloma/lymphoma and primary spine tumors) and surgical approaches (Type I: Cervical spine surgery either anterior and/or posterior stabilization with or without corpectomy, Type II: Thoracolumbar posterior instrumentation and decompression, and Type III: Thoracolumbar corpectomy). ResultsPreoperative embolization was performed in 48 patients. Hypervascular angiographic appearance was found in 22 (46%) and capillary blush in 26 (54%) embolized patients. Total embolization (>80% reduction of tumor blush) was achievable in more than half of the embolized patients (61%), and less amount of blood loss was observed in these patients (median blood loss = 900ml) compared with those who achieved partial (<50%) and subtotal (50–90%) embolization (1600ml and 1350ml respectively). Blood loss was also lower in those who achieved proximal embolization and those who underwent surgery between 13–24 hours after embolization. When stratified by type of tumor and surgical approaches, blood loss and transfusion requirement were lower in embolized cases of spinal secondaries from HCC & thyroid; and primary spine tumors. In multivariate linear regression, after adjusting for tumor type, type of surgical procedure, invasiveness index, preoperative haemoglobin and operative time, there were no significant differences in the blood loss as well as blood transfusion units between embolized and non-embolized groups. ConclusionsSuccess of embolization in reducing blood loss depends on the extent of embolization, which should be total; and time interval between embolization and index surgery, which should be within 13–24 hours. Preoperative embolization is a useful modality in decreasing intraoperative blood loss in cases of spinal metastases from HCC, thyroid and primary spine tumors.