Navigated Intraoperative 2D Ultrasound in High-Grade Glioma Surgery: Impact on Extent of Resection and Patient Outcome

Aims: Maximizing extent of resection (EOR) and reducing residual tumor volume (RTV) while preserving neurological functions are the main goal in the surgical treatment of gliomas. Navigated intraoperative ultrasound (N-ioUS) is a real-time imaging technique which, combining the advantages of ultrasound and conventional neuronavigation (NN), allows for overcoming the limitations of the latter, such as brain shift and brain deformation. In this study, we evaluate the impact of real-time NN combining ioUS and preoperative magnetic resonance imaging (MRI) on maximizing EOR in glioma surgery compared with standard NN.

Methods: We retrospectively reviewed a series of 60 cases: 9 World Health Organization Grade (WHO) III and 51 WHO IV operated on for supratentorial gliomas, 31 operated under the guidance of N-ioUS, and 29 resected with standard NN. All cases were evaluated considering age, location of the tumor (30 eloquent and 40 noneloquent), pre- and postoperative Karnofsky Performance Status, EOR, and, if any, postoperative complications. Volumetric preoperative and 48 hours postoperative MRI was used to determine EOR.

Results: The rate of gross total resection (GTR: EOR = 100%) in NN group was 44.8% and EOR≤ 90% 10.3%, whereas in N-ioUS group a 61.2% GTR rate was obtained with a 6.4% rate of EOR≤90%. The rate of RTV 1 cm³. In tumors located nearby eloquent areas, N-ioUS was successfully combined with cortical and subcortical mapping techniques.

No conflict of interest has been declared by the author(s).