Role of postoperative imaging in neuro-oncology

Postoperative imaging in primary and secondary brain tumors is becoming challenging due to advancements in molecular genetic classification of brain tumors influencing advancing treatment options. In this review, we summarize the standard-of-care practice, commonly encountered clinical and postoperative imaging issues. The timeline for follow-up imaging in low-grade, high-grade, and secondary tumors is discussed, particularly in reference to tumor and treatment-related effects. Standardized imaging protocols are essential for postoperative evaluation, which should always be read in the context of previous imaging. Where possible, advanced magnetic resonance imaging techniques, including multiparametric diffusion, perfusion, and spectroscopy imaging, should be used to differentiate between recurrent tumor and treatment-related changes. Surgical complications are often seen in the immediate and acute postoperative period and chemoradiotherapy-related complications following several weeks to months. The main aim of postoperative imaging is to evaluate expected and unexpected findings for appropriate management. Background information of tumor molecular genetics, histological grade, patient clinical status, and treatment given is essential for interpreting postoperative imaging.