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Clinical History:
This 23-year-old woman presented to clinic complaining of right thigh pain over the last year, worse with weightbearing and at night. The subsequent plain film radiograph and MR examination revealed a lesion within the distal femoral metadiaphysis. Biopsy showed findings consistent with a nonossifying fibroma.
Diagnosis:
Nonossifying fibroma
MR Technique:
Scans were acquired on a 3 T Siemens Verio MR unit. (A) Coronal pre-contrast turbo spin echo fat-suppressed T2-weighted (TR/TE 4000/100 ms, scan time 2:20 min:sec) images were obtained as well as (B) coronal spin echo T1-weighted (TR/TE 672/21 ms, scan time 4:57 min:sec) images, and (C) coronal post-contrast spin echo fat-suppressed T1-weighted images. Slice thickness was 3 mm in each instance.
Imaging Findings:
An approximately 3 by 2 cm distal femoral shaft mass exhibits low and high signal intensity on T1 and T2-weighted images, respectively. This lesion demonstrates a sclerotic, expansile appearance on plain film radiography. No cortical disruption is apparent, and although the lesion itself enhances, no associated enhancing soft tissue mass is present.
