RADIOLOGICAL FEATURES OF BRAIN METASTASES ON MRI

Brain metastases are the most common intracranial tumors in adults, accounting for approximately 20–40% of all brain neoplasms. Magnetic Resonance Imaging (MRI) plays a central role in the detection, characterization, and monitoring of metastatic brain lesions due to its superior soft tissue contrast and multiplanar capability. This article reviews the key radiological features of brain metastases on MRI, including conventional sequences and advanced imaging techniques. Emphasis is placed on lesion morphology, enhancement patterns, surrounding edema, and differential diagnostic considerations. Current literature and statistical data are also analyzed to highlight the diagnostic accuracy of MRI in clinical practice.脑转移瘤（Brain metastases）是成人最常见的颅内肿瘤，约占所有脑肿瘤的20%~40%。磁共振成像（Magnetic Resonance Imaging, MRI）因其优异的软组织对比度与多平面成像能力，在脑转移病灶的检测、定性与监测中居于核心地位。本文综述了脑转移瘤在磁共振成像下的关键放射学特征，涵盖常规序列与先进成像技术，重点阐述病灶形态、强化模式、周围水肿及鉴别诊断要点，并分析当前相关文献与统计数据，以阐明磁共振成像在临床实践中的诊断准确性。