Extra osseous uptake of 99mTc-MDP in psoas muscle on bone scintigraphy: Importance of SPECT/CT imaging

Document Type : Case Report


Nuclear Medicine Research Center, Mashhad University of Medical Sciences, Mashhad, Iran


Incidental extra-osseous uptake of 99mTc-MDP on bone scintigraphy has been frequently reported in the literature; however, calcification of the psoas muscle is a rare condition, which has been reported on magnetic resonance (MR) and computed tomography (CT) imagings. Here we report a 67-year-old woman with acute paraplegia and low back pain who was referred for a 99mTc-MDP bone scintigraphy. A destructive lesion in lumbar vertebrae was identified; which was compatible with the findings on CT scan. The planar images also showed focally increased activity in the right pelvis, which was confirmed as extra osseous MDP uptake in psoas muscle on the SPECT/CT images.


Main Subjects

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