Intraoperative ultrasound assistance in resection of intracranial meningiomas

Abstract

Objective: Intracranial meningiomas, especially those located at anterior and middle skull base, are difficult to be completely resected due to their complicated anatomy structures and adjacent vessels. It's essential to locate the tumor and its vessels precisely during operation to reduce the risk of neurological deficits. The purpose of this study was to evaluate intraoperative ultrasonography in displaying intracranial meningioma and its surrounding arteries, and evaluate its potential to improve surgical precision and minimize surgical trauma.

Methods: Between December 2011 and January 2013, 20 patients with anterior and middle skull base meningioma underwent surgery with the assistance of intraoperative ultrasonography in the Neurosurgery Department of Shanghai Huashan Hospital. There were 7 male and 13 female patients, aged from 31 to 66 years old. Their sonographic features were analyzed and the advantages of intraoperative ultrasonography were discussed.

Results: The border of the meningioma and its adjacent vessels could be exhibited on intraoperative ultrasonography. The sonographic visualization allowed the neurosurgeon to choose an appropriate approach before the operation. In addition, intraoperative ultrasonography could inform neurosurgeons about the location of the tumor, its relation to the surrounding arteries during the operation, thus these essential arteries could be protected carefully.

Conclusions: Intraoperative ultrasonography is a useful intraoperative technique. When appropriately applied to assist surgical procedures for intracranial meningioma, it could offer very important intraoperative information (such as the tumor supplying vessels) that helps to improve surgical resection and therefore might reduce the postoperative morbidity.

Keywords: Intraoperative ultrasonography; intracranial meningioma.

Figure 1

Preoperation, intraoperation and postoperation situation of patient 17 with left sphenoid ridge and middle cranial fossa giant meningioma. A-C. Pre-operative MRI images showed a giant meningioma with homogenously enhancement located on the left sphenoid ridge and middle cranial fossa; D. Brain MRA indicated that the left ICA and MCA were compressed away by the tumor, and the left MCA was pushed inferiorly and upward; E-F. VR further revealed the relationships of the tumor and the adjacent vessels. After “cut” the partial tumor, the engulfed arteries were exposed clearly; G. The intra-operative neuronavigation could also detect the vessels surrounding the tumor from different points of view; H-J. Intraoperative ultrasonography could determine the tumor borders, the tumor supplying arteries and blood flow (the colorful dots in the images), and the relationships of the tumor and its supplying vessels; K. During the operation, the important arteries could be carefully protected (the upper white arrow) while the tumor (the left white arrow) was safely resected. The right white arrow showed the lateral cleft vessels; L. Post-operative contrast MRI scan showed the tumor was completely removed without tumor residual

Video 1

Intraoperative ultrasound angiography for intracranial meningioma resection