Ultrasonography monitoring with Superb Microvascular Imaging technique in brain tumor surgery

• Published in: World neurosurgery 2017-01, Vol.97, p.749.e11-749.e20
• Main Authors: Ishikawa, Mami, MD PhD, Ota, Yasushi, MD PhD, Nagai, Mutsumi, MD PhD, Kusaka, Gen, MD PhD, Tanaka, Yuichi, MD PhD, Naritaka, Heiji, MD PhD
• Format: Article
• Language: English
• Subjects: Adult; Aged; Brain Neoplasms - diagnostic imaging; Brain Neoplasms - surgery; Female; Humans; Intraoperative monitoring; Male; Microvascular imaging; Microvessels - diagnostic imaging; Microvessels - surgery; Middle Aged; Monitoring, Intraoperative - methods; Neuronavigation - methods; Neurosurgery; Neurosurgical Procedures - methods; Tumor vessels; Ultrasonography; Ultrasonography, Interventional - methods
• ISSN: 1878-8750; 1878-8769
• DOI: 10.1016/j.wneu.2016.10.111

Abstract Background Neuronavigation based on preoperative magnetic resonance imaging (MRI) has been developed as a useful tool to improve visibility of the surgical site in the operative field. Ultrasonography (US) monitoring has also been used as a reliable imaging technique, providing real-time information during neurosurgical operations. We combined the latest innovative imaging technique for detecting very low-flow components, Superb Microvascular Imaging (SMI), with US monitoring during brain tumor surgery. Case Description Fifteen patients diagnosed with brain tumor (8 malignant and 7 benign) underwent neurosurgery with US monitoring using an Aplio 400/500 US system with the new SMI technique (imaging frequency: 10-12 MHz, frame rate: 28-31 Hz). Features of the SMI images in the grayscale mode include (1) visualization of low-velocity flow with minimal motion artifact, (2) high resolution of images, and (3) high frame rates. The tumors, tumor vessels, compressed and shifted normal vessels, and cistern were clearly visualized on the SMI images in the grayscale mode, detailing the characteristics of normal brain tissue (vertically penetrating, fine, straight vessels), glioblastoma (rounding, dilating, and bending vessels), low-grade glioma (fine and straight vessels), meningioma (many large and branching vessels), and lymphoma (less vascular, low echoic tumor) and demonstrating the tumor-defined border. We also performed biopsies under US monitoring with SMI. Conclusions We combined SMI technique with US monitoring during brain tumor surgery and observed normal and tumor vessels. Further research is important for the development of more precise and reliable neurosurgery.