Selcuk G.
Anadolu Medical Center, neurosurgeon,

Introduction. Intraoperative multimodal neuromonitoring (IONM) is used and accepted as a useful tool in recognizing possible postoperative neurological deficits in any kind of spinal surgery. This tool is becoming nearly mandatory especially in intradural tumor surgery with many aspects including legal issues. Materials and methods. Here we present our 46 cases with lumbar schwannomas as a comparison of IONM era. IONM was used in last 25 cases according to the trend of surgical approach as a technological guidance. In addition,recent 29 cases had unilateral minimally invasive laminectomy approach as a new surgical concept to avoid iatrogenic instability. Furthermore, total resection of schwannomas in lumbar area leads to improvement in the health quality of life (HQRL) of a patient after surgery. Classical approach in microsurgical resection of schwannomas requires cutting the fiber of origin in schwannomas and trigerred EMG probe as a part of IONM can be used in determination of this root to presume better neurological result. However, whether it causes any change in surgical strategy or not, is still not clear, as spinal roots which give rise to schwannomas have been frequently found to be nonfunctional. Results. Our early postoperative results in 46 patients with lumbar schwannomas were satisfactory, as we did not recognize any additional motor deficit after the surgery. Some patients had sensorial deficits before operation and this remained the same. All the patients have had a control MRI with no residual or recurrence of tumor.
Conclusions. Our study shows that IONM may not influence the surgical strategy and the neurological outcome of the patients according to HQRL results regarding surgical resection of lumbar schwannomas. Because the fiber of origin of the tumor can be clearly identified during microsurgery.