Safety and accuracy of frameless electromagnetic-navigated (AXIEMTM)-guided brain lesion biopsies: a large single-unit study

Brain biopsies are required to establish a definitive histological diagnosis for brain lesions that have been identified on imaging in order to guide further treatment for patients. Various navigation systems are in use but little up to date evidence is available regarding the safety and accuracy of a frameless, electromagnetic technique to target brain lesions. Data was collected retrospectively on all patients that had brain biopsies at our institution from 01/01/2010 to 31/12/2017. Operation notes, neuropathology reports, and clinical notes on electronic patient record were used to determine whether biopsy of adequate identifiable abnormal tissue was achieved, whether a definitive diagnosis was established, any adverse events occurred, and if a repeat biopsy was carried out. Three hundred seventy-one AxiEM (Medtronic, Minneapolis, USA)-guided brain tumor biopsies were performed in this 8-year period. Three hundred forty-nine (94.07%) procedures provided definitive tissue diagnosis, 22 (5.93%) were non diagnostic; in 6 cases (1.62%), repeat biopsy was performed and adverse events which caused clinical compromise were observed in 4 patients (1.08%). The AxiEM is a fast, effective, and safe frameless and pinless neuronavigational system. It offers a high degree of accuracy required for the establishment of a definitive diagnosis, permitting optimal further treatment, and thus improving patient outcomes.