MR Imaging in a case of severe anorexia nervosa: the ‘flip-flop’ effect

We report an MR imaging phenomenon that can lead to misinterpretation. The unique appearance of the soft tissues and bone marrow in a 19-year-old severely malnourished woman with anorexia nervosa raised concerns about technical failure or systemic pathology. Due to extreme fat depletion, the T1-weighted images appeared to be fat-suppressed and the fat-suppressed fluid-sensitive images appeared to be non-fat-suppressed ("flip-flopped"). Failure to recognize the influence of a patient's overall nutritional status on MR images may cause confusion and misdiagnosis.