M. De Lima Oliveira, H. Picarelli, A. Blassioli Barbosa, S. Brasil Lima, M. Jacobsen Teixeira, E. Bor-Seng-Shu
Department of Neurology, University Hospital, University of São Paulo – São Paulo, Brazil
Objective: Radical resection of brain metastases can be associated with better outcome. The gold standard intraoperatory method to detect residual tumors is magnetic resonance (RM). However this method requires long image acquisitions time, intravenous contrast (gadolinium) to disclose residual lesions and is restrict to some neurosurgical centers. Among the image methods, intra operatory ultrasound (IOUS) has been a reliable tool for assessing residual lesions after macroscopic tumor excision.
Material and Methods: Thirty six patients with presumed diagnosis of brain metastases (BM) were underwent a surgery with IOUS to pint point tumors, delineate their margins and intra operatory control resection. A total 46 lesions were removed by microscopic surgeries. IOUS was performed in all operations. A prospective study compared the last 2D IOUS control after tumor resection with pos operatory magnetic resonance (MRI) and enhanced contrast tomography (CT) in terms of quality in residual lesion detection. Control MRI and enhanced CT were performed in 75% of patients. Control CT and MRI were considered when it was performed until five months after surgery.
Results: IOUS was generally concordant with control MRI and CT in 89,6% and 80% of cases respectively. When IOUS was positive or negative for the presence of tumor, the concordance with MRI was 80% and 89,5% respectively. When IOUS was negative for tumor the control CT concordance was 94%. Positive IOUS for tumor had control CT concordance in just 28,6% of cases.
Discussion: IOUS is a practical supporting method for the control of intraoperative resection BM, but further studies comparing this method with other intraoperative exams are needed to evaluate its validity.
Key words: brain metastasis resection, control magnetic resonance, control tomography, ultrasound.