MRI (gold standard) refers to magnetic resonance imaging recognised as the most accurate and reliable diagnostic tool for detailed soft tissue visualisation and anatomical assessment. It matters in clinical practice because it provides high-resolution images without ionising radiation, enabling precise diagnosis and treatment planning for conditions such as neurological disorders, musculoskeletal injuries, and tumours. A key example is its use in detecting multiple sclerosis plaques, where MRI’s sensitivity directly influences early diagnosis and management.