gms | German Medical Science

Objective: In recent years techniques for intraoperative real-time localization and hemodynamic monitoring have gained increasing interest in the surgical management of AVMs. Besides the standard imaging techniques like MRI and angiography, intraoperative colour duplex sonography has proven to be of great value for the identification of feeding arteries and for an understanding of changes in hemodynamics during AVM resection. In addition to real time imaging modalities, the application of navigation techniques has been recommended in deep-seated AVMs. A direct integration of colour (C-) mode scans into the navigation system can be a valuable adjunct during angioma surgery. In this study we present our first experience using image-guided colour duplex sonography for the resection of AVMs.

Methods: From 2002 to 2005 navigated intraoperative ultrasound was used in 10 patients, who underwent microsurgical resection of a supratentorial AVM. All patients underwent preoperative angiography. The neuronavigation (VectorVision², BrainLAB) was based on preoperative MRI-scans. Intraoperative navigated ultrasound was performed using an external ultrasound scanner (Aplio, Toshiba) or the IGSonic device, that can be integrated into the navigation platform. Complete occlusion of the AVM was documented by postoperative angiography in all cases.

Results: Image fusion with preoperative images was performed without difficulties. The AVM was easily localized in B-mode and C-mode in all cases. Arterial feeders were identified using C-mode in alignment with the corresponding MRI image. Changes in hemodynamics could be visualized and a complete resection could be documented by using duplex or triplex techniques. The sonographic results could be verified by postoperative angiography in all cases.

Conclusions: Intraoperative colour duplex sonography provides valuable real-time hemodynamic information during angioma resection. The preoperative MRI data set together with the hemodynamic information facilitates anatomical understanding of the complex vasculature as the preoperative MRI-data set helps to interpret the sonographic data. Thus, we feel that this technology is beneficial for AVM resection.