Surgical results of the resection of spinal meningioma with the inner layer of dura more than 10 years after surgery.

Most spinal meningiomas arise from the thoracic dura in middle-aged and elderly women. Simpson grade 1 resection is recommended to avoid recurrence. For ventral and ventrolateral tumors, reconstruction after total dural resection is difficult, and spinal fluid leakage is likely. To overcome this concern, Saito et al. developed the technique of resecting the tumor with the inner dural layer, preserving the outer dural layer. Although meningioma rarely recurs, the recurrence period is approximately 8 years postoperatively. No studies have evaluated long-term (> 10-year) outcomes of the Saito method. Here, we report 10 cases of the Saito method with > 10-year follow-up and compare outcomes with those of other standard approaches. Twenty-nine pathology-confirmed meningioma patients underwent surgery in our department, ten with the Saito method. We investigated resection method (dura mater treatment), pathological type, and recurrence and compared pre- and postoperative clinical findings. The median follow-up was 132 months. Recurrence occurred after Simpson grades 3 and 4 resection. Simpson grades 1, 2, and the Saito method resulted in no recurrence. Neurological symptoms improved in all patients at final follow-up. This is the first report of long-term outcomes of the Saito method. The method achieved good neurological improvement with no recurrence in > 10-year follow-up.