Imaging Techniques: Magnetic Resonance Imaging (MRI)
摘要
Magnetic resonance imaging (MRI) is a crucial tool for evaluating bone tumors, providing high-resolution anatomic detail and functional information for diagnosis and clinical management. Optimizing sequence selection, anatomic coverage, and imaging orientation is essential to maximize diagnostic yield while maintaining reasonable scan times. While intermediate-weighted sequences such as proton density are the primary sequences in general musculoskeletal imaging due to improved depiction of cartilage and ligaments, T1-weighted sequences are instead the mainstay in bone tumor imaging due to superior evaluation of bone marrow and soft tissue. Fat suppression is also essential to confirm true contrast enhancement after gadolinium administration and to detect intralesional fat, the presence of which suggests a benign process or treatment response. Contrast-enhanced MRI aids in lesion characterization and assessment of therapeutic response by highlighting necrosis and helps detect recurrence. Accurate MRI interpretation requires familiarity with MRI artifacts and strategies to minimize them, including faster acquisition techniques and metal artifact reduction sequences. Beyond conventional imaging, advanced approaches such as perfusion imaging and zero echo time (ZTE) offer insights into treatment response and potential workflow improvements. Lesion MRI signal characteristics, including fluid, edema, and hemorrhage, combined with morphology, location, and anatomic relationships, provide essential information for accurate diagnosis, staging, and guiding management.