Computed Tomography and Magnetic Resonance Imaging Manifestations of Spinal Monostotic Fibrous Dysplasia.

Aim: The purpose of the study was to analyze and summarize the computed tomography (CT) and magnetic resonance imaging (MRI) findings of spinal monostotic fibrous dysplasia (MFD) as well as evaluate the clinical value of CT and MRI in MFD diagnosis. Materials and Methods: CT (n = 4) and MRI (n = 5) images of six patients with pathologically confirmed spinal MFD were examined. The assessed image features included location, shape, rib involvement, vertebral collapse, margin, attenuation, and sclerotic rim on CT, as well as signal intensity, dark signal rim, and enhancement pattern on MRI. Results: In total, four of six patients underwent CT scanning. The most common findings on CT scanning were expansile lesions (n = 4), sclerotic rims (n = 4), and ground-glass opacity (GGO) (n = 4). In total, five of six patients underwent MRI. The lesions were low-signal intensity (n = 2), low-to-isointense signal intensity (n = 1), and low-signal intensity with several isointense portions (n = 2) on T1-weighted imaging (T1WI). The lesions were low-signal intensity (n = 1), isointense to high intensity (n = 1), and isointense signal intensity with several high portions (n = 3) on T2WI. A dark signal rim was found in most cases on T1WI and T2WI (n = 4). The lesions (n = 2) showed obvious enhancement. Conclusions: The CT and MRI manifestations of spinal MFD have the following characteristics: expansile lesion, GGO, sclerotic rim, and no obvious soft-tissue mass. The combined use of CT and MRI examinations is necessary for patients with suspected spinal MFD.