gms | German Medical Science

Objective: Due to the technical capabilities in advanced application of ultrasound and high resolution real-time viewing intraoperative ultrasound technology turned out to be a simple tool in brain tumor surgery. However sensitivity and specificity of B-mode ultrasound is limited in detection of tumor remnants as well as in differentiation of oedema and vascular structures. Therefore, our investigations focused on contrast enhanced ultrasound and its impact on intraoperative imaging in a 3 D – navigated scenario.

Methods: Our preliminary series included fifteen glioma patients. Intraoperatively a 3 D-reconstructed transdural ultrasound after contrast agent application (SonoVue^®) with a linear array respectively a phased array (Toshiba^®) was performed and integrated into the neuronavigation (LOCALITE^®). The ultrasound probe was tracked and calibrated. After resection another contrast enhanced US scan was performed to verify tumor remnants. 3 D-Ultrasound datasets were analysed in comparison to pre – and postoperative MRI – data.

Results: In all cases an uptake of the contrast agent was observed and the tumor margins and configuration could be identified. The real time - integration of the US data in the 3 D-neuronavigation was possible in all cases. The tumor as well as other anatomical structures could be identified in the compare panel with a minimal deviation up to 2 mm in comparison to the preoperative MRI. Additionally the contrast uptake revealed a high overlap to contrast enhanced MRI areas (Figure 1 [Fig. 1]).

Conclusions: The reconstructed 3 D-contrast enhanced ultrasound seems to be an additional, useful method for intraoperative tumor visualization as well as tumor remnants confirming an effective resection control in glioma surgery.