Application Of High Field Intraoperative MRI Combined With Neuronavigation In Functional Areas Glioma Surgery

BackgroundFor the functional areas of glioma patients, the surgical removal of the tumor is likely to cause postoperative language, sports and other neurological dysfunctions, which will seriously affect the quality of life of patients, detrimental to their survival prolonged. So how to maximize the removal of the tumor, while minimizing the extent of the damage to functional areas, is the highest goal of glioma brain surgery, but also a major challenge for neurosurgeons. Objective:Preliminarily discuss the application experience of high field Intraoperative MRI combined with neuronavigation in functional areas glioma Surgery. Methods:We retrospective analysis 37 cases of patients who accepted the Intraoperative MRI and Functional Neuronavigation in Department of Neurosurgery of the First Affiliated Hospital of Zhengzhou University from 2012 December to 2014 June. The inclusion criteria: ①Combining imaging data and physical examination, the initial diagnosis of glioma; ②lesions involving functional areas or near; ③The muscle strength of patients’ bilateral limbs were ≥IV equally; ④The body fit, and can conduct MRI scan; ⑤The patients have good cooperation willingness and ability; ⑥without the contraindication of MRI scan. Before the operation, all of these patients had preoperative signed informed consent, and conducted Functional Areas Glioma excision aided by 3T Intraoperative magnetic resonance imaging and the functional neuronavigation.Using 3T MRI to finish preoperative scans, application Bold-f MRI reconstructed cortical function, marking an important structural function areas, and apply DTI reconstruct pyramidal tract. After fusing these important functional structure images, we will import it into the nervous navigation system for neurological navigation under the microscope. During the operation, we combined with the application of 3T Intraoperative MRI to update the image of tumors and functional structure. Using computer software to measure the distance between the edge of the tumor and the pyramidal tract and records. After preoperative, intraoperative scanning,we will use navigation workstation to calculate tumor volume, and then calculate the percentage of tumor resection(i.e., removal rate). We will evaluate the preoperative and postoperative neurological function of patients respectively,and statistics of neurological dysfunction incidence of postoperative. ResultsAmong the 37 patients enrolled in, 17 cases(45.9%) patients using intraoperative MRI scans only once, and 9 cases(24.32%) patients were removed the lesion totally, then 20 cases got excision further, finally 22 cases(59.45%) were removed the lesion totally. The application of high field intraoperative MRI combind with neuronavigation improve the degree of resection of the tumors( from 76.89%± 27.18% to 92.39%±12.31%),the difference was statistically significant(paired t test, P <0.05).We marked the closest distance between the tumor and the reconstruction of post-pyramidal edge D, There is significant difference between the group(the closest distance between tumor and the reconstruction of post-pyramidal edge >5mm) and the group(the closest distance between tumor and the reconstruction of postpyramidal edge <5mm) in the total removal rate, the difference was statistically significant(Fisher exact test, P <0.05),,and the total resection rate of group >5mm was significantly higher than that of group <5mm. There is significant difference between Preoperative Karnofsky score(78.51 ± 11.09) and postoperative Karnofsky score(78.51 ± 13.37), the difference was not statistically significant(paired t test, P> 0.05). After 6 months of follow-up,we found that most patients with muscle strength has returned to normal or better than before,only 2 cases(5.40%) patients appeared permanent neurological dysfunction and did not returned to the preoperative level. Conclusions:1. The application of high field intraoperative MRI combind with neuronavigation can significantly enhance the extent of resection in functional areas glioma surgery2. Whether the distance between reconstructed pyramidal tract margin and tumor margin more than 5mm or not is the crucial factor to influence the total resection rate in functional areas glioma surgery3. High field intraoperative magnetic resonance imaging combined with neuronavigation can help neurosurgeon make operation strategy better、remove the tumor in the high limit and reduce the incidence of postoperative neurological dysfunctions.