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The helmet sign: Physiologic radioactive accumulation after 131I therapy--a case report
Lorraine Ash1, Bohdan Bybel, Donald Neumann
1Department of Diagnostic Radiology, Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA.
Abstract:
After 131I radioablative treatment, a 51-y-old woman underwent whole-body (131)I scanning, which revealed intense uptake along the periphery of the skull. The patient disclosed that she had not washed her hair because she had obtained a new hairstyle between the 131I treatment and the scan. The intense uptake along the periphery of the skull represented radioactive physiologic accumulation at the patient's scalp.
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