Predictive value of inferior fronto-occipital fasciculus (IFO) DTI-fiber tracking for determining the extent of resection for surgery of frontal and temporal gliomas preoperatively.

ABSTRACT

AIM: This work reports the analysis of the relationship between inferior fronto-occipital fasciculus (IFO), neoplastic lesions and surgical resection, in patients operated for gliomas located in the frontal, temporal and insular lobes of the dominant hemisphere. Aim of the study is evaluating the predictive value of inferior fronto-occipital fasciculus DTI-fiber tracking (FT) for determining the extent of resection preoperatively. METHODS: We selected 38 cases affected by lesions located in the frontal, temporal and insular lobes of the dominant hemisphere, which were related to the trajectory of the IFO. For each patient preoperative and postoperative MR images and DTI-FT were loaded into the neuronavigation system and merged; volumetric scan analysis was used for establishing tumor location and topography, as well as the volume of the lesion and of the residual tumor. All preoperative fiber tracking datasets were evaluated and the position of the tract (IFO) compared to the tumor was recorded. Postoperative MR scans were then compared with DTI-FT, in order to evaluate the correspondence between the resection boundaries and the trajectory of the fiber tract. RESULTS: Amongst the cases in which the IFO was inside the lesion, we found only incomplete resections (5 subtotal and 6 partial resections), while considering the cases in which the IFO was located outside the tumor, it was possible to perform a relevant (total/subtotal) resection in 18 of them (78%). CONCLUSION: FT of the inferior frontal-occipital fasciculus predicts the possibility and the extent of the resection for a frontal, temporal and/or insular lesion of the dominant hemisphere.