Abstract
A 61-year-old woman with monostotic Paget's disease of the third lumbar vertebra was reported with MR image findings. Lateral plain radiograph of the vertebra showed a classic picture-frame appearance. By MR imagings cortical thickening was depicted as hypointense regions on both T1-weighted and T2-weighted images. Areas of slightly increased signal intensity was recognized within the hypointense areas on T2-weighted images. Round or oval foci of reduced signal intensity and foci of high signal intensity were seen in the medullary cavity on T1-weighted images. The spinal process was apparently hypointense on T1-weighted images and slighty hyperintense on T2-weighted images. The basivertebral vein showed hypointensity on T1-weighted images, implying an increase in blood flow. Biopsy specimens taken from the spinal process revealed a characteristic mosaic pattern, with an increased activity of osteoclasts and osteoblasts, and replacement of the marrow cavity by fibrous connective tissue having some edematous zones.
