The Use of Intraoperative Ultrasound during Endoscopic, Endonasal Approach to the Anterior Skull Base for Resection of a Tuberculum Sella Meningioma: A Technical Note

Abstract

Background: Neurosurgical and skull base centers use neuronavigation systems to create three-dimensional visualization of the surgical target based on preoperative imaging; however, this technique is limited because of registration error and because of the movement of brain components once the tumor is debulked during surgery. Because ultrasound offers a live image of the surgical target, it can account for this brain shift to accurately reflect the location of vital structures during surgical resection. Although, accounting for these intraoperative changes have been resolved by the use of conventional ultrasound during microscopic skull base surgery, the use of an appropriately designed probe for EEA has not been described. Objective: The aim of this technical note is to describe the initial clinical application of the ultrasound in an expanded endoscopic, endonasal approach. Materials and Methods: The authors used the Prosound Alpha 7 Premier (Aloka Co., LTD, Tokyo, Japan) ultrasound to assist with capturing real-time images of the surgical window, including the tumor and surrounding structure. The case example describing the application of the device during surgery is discussed. Conclusion: This is the first described case using an ultrasound during EEA. This case suggests that the use of this ultrasound during EEA is feasible and its potential utility is vast. This device guided the authors intraoperatively to localize the tumor and to capture live images of it and its surrounding structures. Further studies are required to confirm its clinical impact and clarify its limitations when applied to other areas in the sagittal and coronal planes.