Full-course resection control strategy in glioma surgery using both intraoperative ultrasound and intraoperative MRI

Abstract

BackgroundIntraoperative ultrasound(iUS) and intraoperative MRI (iMRI) are effective ways to perform resection control during glioma surgery. However, most published studies employed only one modality. Few studies have used both during surgery. How to combine these two techniques reasonably, and what advantages they could have for glioma surgery are still open questions.MethodsWe retrospectively reviewed a series of consecutive patients who underwent initial surgical treatment of supratentorial gliomas in our center. We utilized a full-course resection control strategy to combine iUS and iMRI: IUS for pre-resection assessment and intermediate resection control; iMRI for final resection control. The basic patient characteristics, surgical results, iMRI/iUS findings, and their impacts on surgical procedures were evaluated and reported.ResultsA total of 40 patients were included. The extent of resection was 95.43 ± 10.37%, and the gross total resection rate was 72.5%. The median residual tumor size was 6.39 cm3 (range 1.06–16.23 cm3). 5% (2/40) of patients had permanent neurological deficits after surgery. 17.5% (7/40) of patients received further resection after the first iMRI scan, resulting in four (10%) more patients achieving gross total resection. The number of iMRI scans per patient was 1.18 ± 0.38. The surgical time was 4.5 ± 3.6 hours. The pre-resection iUS scan revealed that an average of 3.8 borders of the tumor were beside sulci in 75% (30/40) patients. Intermediate resection control was utilized in 67.5% (27/40) of patients. In 37.5% (15/40) of patients, the surgical procedures were changed intraoperatively based on the iUS findings. Compared with iMRI, the sensitivity and specificity of iUS for residual tumors were 46% and 96%, respectively.ConclusionThe full-course resection control strategy by combining iUS and iMRI could be successfully implemented with good surgical results in initial glioma surgeries. This strategy might stabilize resection control quality and provide the surgeon with more intraoperative information to tailor the surgical strategy. Compared with iMRI-assisted glioma surgery, this strategy might improve efficiency by reducing the number of iMRI scans and shortening surgery time.

Surgical Management and Advances in the Treatment of Glioma

“…53 The combination of ioUS for real-time intraoperative resection monitoring coupled with subsequent iMRI for the assessment of resection completion (the so-called full-course resection strategy) was investigated in a recent retrospective study of 40 patients. 54 This combination of ioUS and iMRI yielded a final EOR rate of 95.43% and GTR rate of 72.5%, with reduced surgical time and fewer total MRIs compared with other studies of iMRI. Although preliminary, these results demonstrate the ease of combining ioUS with other methods or assessing EOR.…”

Navigated intraoperative ultrasound in pediatric brain tumors

“…Nevertheless, the performance of iUS in localization of residual tumor is considered promising. Multiple studies have reported that navigated iUS shows to be a good addition to the neurosurgical armamentarium [9,13,14,[17][18][19][20][21]. There is not yet a clear consensus in literature on the sensitivity and specificity of iUS in detecting residual tumor.…”

“…Based on previous studies [9,10,13,14,[17][18][19][20][21][22], we defined that iUS has a good diagnostic value in detecting residual tumor if a sensitivity and specificity of more than 80% was achieved.…”

Application of intraoperative ultrasound in the resection of high-grade gliomas

“…The main technical limitations found in some study series include artifacts after opening the dura mater, variability in the frequency and amplitude of mechanical pulsation, and uncertainty in evaluating deep lesions ( 38 ). According to the latest study by Hou et al ( 41 ), combining the SWE mode with superb microvascular imaging (SMI), it was found that in the SWE mode, HGG and LGG showed completely different values under Young's modulus, with a diagnostic threshold for distinguishing HGG and LGG at 13.05 kPa. In the SMI mode, the tissue surrounding the HGG was described as having distorted blood flow signals, while the HGG tissue itself exhibited dilated and bent vessels.…”

“…This suggests a combined approach using imaging tools. A recent retrospective study by Hou et al ( 41 ) included 40 patients who underwent IOUS and IMRI during glioma resection. IOUS was used for preoperative and intraoperative evaluations, while IMRI was used for final scanning to determine whether additional resection was necessary.…”