The use of delayed craniotomy in selective patients for pre-resection embolization of meningiomas

Introduction: Preoperative embolization of meningiomas may safely reduce blood loss and improve ease of resection. By delaying the craniotomy for resection from the time of embolization, necrosis occurs making the tumor easier to resect. Preoperative MRI was analyzed to predict tumors amenable to embolization. Methods: Imaging studies from 1988 through 1999 were reviewed to determine characteristics of susceptible tumors. Patients treated between 1997 to 2000 were reviewed to determine the time of embolization to craniotomy, symptoms of increased mass effect, evidence of necrosis, and ease of tumor removal. Results: One hundred and two meningiomas were evaluated; 58 tumors were embolized. Thirty-seven tumors lacked accessible feeding arteries or significant vascular blush; 7 were unsuccessfully attempted. When available, preoperative MRI/MRA were evaluated to predict angiographie criteria for success. From 1997 to 2000, 11 patients underwent craniotomy within 3 days of embolization (Group A) and 9 patients had surgery at least 5 days after embolization (Group B). Neither group had evidence of increased mass effect, but Group B had higher incidence of necrosis and shortened length of operation. Conclusion: Embolization was performed successfully in the majority of patients. MRI/MRA characteristics help predict susceptible tumors. By delaying craniotomy at least 5 days, tumor necrosis and decreased operative time may be gained without losing hemostatic effect.