The Role of Intraoperative Imaging Modalities in Surgical Resection of Supratentorial Gliomas: A Review of 300 Cases

Intraoperative tumor visualization is an essential factor for successful glioma surgery. The aim of this study was to examine the extent of glioma resection and the patients' postoperative clinical conditions after resection with intraoperative imaging guidance (iMRI and "modern" ultrasound combined with neuronavigation [iUS]) and without intraoperative imaging guidance.

We retrospectively analyzed the clinical data of 300 glioma patients who underwent surgery for supratentorial low-grade gliomas and high-grade gliomas at our department between 2015 and 2022.

Among all the patients, 65 (21.7%) underwent tumor resection under iMRI guidance, and 35 (11.7%) underwent tumor resection under iUS guidance. Two hundred patients (66.7%) underwent tumor resection without intraoperative imaging control. Gross total resection (GTR) was achieved in 125 patients (41.7%) in the entire cohort. GTR was significantly more common under iMRI (56.9%) and iUS (57.1%), than without intraoperative imaging guidance (34%) ( P = .001). The mean extent of tumor resection of contrast enhancement was the highest in the iMRI subgroup (96.6%), followed by the iUS subgroup (93.2%) and the subgroup without intraoperative imaging (92%) ( P = .002). The 2 most common postoperative new neurological deficits were cognitive deficits (8%) and speech disorders (7.3%). Patients without intraoperative imaging guidance had weakness significantly more often (odds ratio = 0.520, CI = 0.272-0.994, P = .048) than patients with iMRT or iUS. The Karnofsky Performance Status score at 1 year after surgery was the lowest in patients without intraoperative imaging guidance. Multiple regression analyses for progression-free survival did not reveal any significant differences between the subgroups. Overall survival was significantly worse in patients without intraoperative imaging guidance (odds ratio = 1.534, CI = 1.058-2.225, P = .024) than in patients with iMRI and iUS.

For glioma patients, GTR is more commonly performed under iMRI and iUS, than without intraoperative imaging guidance. Patients without intraoperative imaging control have significantly higher incidences of postoperative weakness and significantly worse overall survival than patients with iMRI and iUS.