Necrosis score, surgical time, and transfused blood volume in patients treated with preoperative embolization of intracranial meningiomas. Analysis of a single-centre experience and a review of literature.

PURPOSE: Several authors have demonstrated that preoperative embolization of meningiomas reduces blood loss during surgery. However, preoperative embolization is still under debate. Aim of this study is the retrospective evaluation of necrosis score, surgical time, and transfused blood volume, on patients affected by intracranial meningiomas treated with preoperative embolization before surgery, compared with a control group treated only with surgery.
METHOD: Twenty-eight patients with meningiomas were subjected to a preoperative embolization with polyvinyl alcohol (PVA). These patients were divided into two groups: group 1, patients with preoperative embolization performed at least 7 days before surgery; and group 2, patients with preoperative embolization performed less than 7 days before surgery. A statistical evaluation was made by comparing necrosis score, surgical time, and transfused blood volume of these groups. Then, we compared these parameters also with group 3, which included patients with surgically treated meningioma who did not undergo preoperative embolization.
RESULTS: Surgery time and transfused blood volume were significantly lower in patients who had been embolized at least 7 days before definitive surgery. Furthermore, large confluent areas of necrosis were significantly more frequent in patients with a larger time span between embolization and surgery.
CONCLUSION: Preoperative embolization with PVA in patients with intracranial meningiomas is safe and effective, as it reduces the volume of transfused blood during surgical operation. However, patients should undergo surgery at least 7 days after embolization, as a shorter time interval has been correlated with a longer surgical time and a higher transfused blood volume.