Practical MRI interpretation of intracranial metastases before and after multidisciplinary management: a pictorial review.

Intracranial metastases represent the most common form of brain tumors in adults. Their diagnosis and post-treatment evaluation are routine tasks in neuroradiology. In this setting, radiologists collaborate with neuro-oncologists, neurosurgeons, radiation oncologists, and other specialists to guide multidisciplinary treatment strategies and assess their response. A well-appointed radiologist should therefore be familiar with current treatment paradigms and their respective manifestations on imaging. This pictorial review begins by reviewing imaging findings of intracranial metastases, emphasizing features germane to management decision-making. Major treatment modalities including radiation, systemic, and surgical approaches, are discussed. The focus of this article is then post-treatment imaging appearance of intracranial metastases, and the major complications associated with each treatment modality are surveyed. Additionally, applications of advanced imaging techniques to differentiate residual or recurrent metastatic disease from treatment-related changes are explored.