MRI findings of serous atrophy of bone marrow with postirradiation changes: A case report

This case report presents serous atrophy of bone marrow (SABM) in a cachexic patient with metastatic squamous cell carcinoma who had undergone radiotherapy. The unique magnetic resonance imaging (MRI) findings of SABM, known as the "flip-flop" phenomenon, were observed in both the irradiated and nonirradiated areas, a finding previously unreported in the literature. The report highlighted the characteristic features of SABM in various MRI sequences, which can be easily misinterpreted as technical errors, leading to unnecessary repetition of MRIs.