Functional outcome of surgery for glioma directly adjacent to pyramidal tract depicted by diffusion-tensor based fiber tracking.

AIM: To investigate the outcome of glioma resection surgery and changes of pyramidal tract (PT) for patients where PT is immediately adjacent to the tumors, which were revealed by diffusion tensor imaging (DTI) based fiber tracking (FT) technique.
MATERIAL AND METHODS: 40 patients enrolled. Preoperative and intraoperative tractography of the PT was performed before and after glioma resection. Motor function was recorded before surgery and 1 week, three to six months after surgery. Distances (D) between intraoperative tractography of the PT and the resection cavity were measured.
RESULTS: 14 patients had transient aggravated or newly motor deficits 1 week after surgery. After 3 to 6 months follow up, only 3 (7.5%) patients had permanent deficits. In 12 (30%) patients, the intraoperative PT tractogram adjoined the resection cavity after tumor removal (D=0). They all had transient aggravated motor deficits after surgery and 3 were permanent. In 19 patients with preoperative motor deficits, 11 (57.90%) had zero D value. In other 21 patients, 1 (4.76%) had zero D value. There was significant difference between these two ratio (p < 0.01).
CONCLUSION: DTI based FT is helpful in protection for the PT during glioma surgery, even if the PT is directly adjacent to the glioma. Patients with preoperative motor deficits faced more risk of persistent aggravated deficits after surgery.