[Imaging of parathyroid disorders].

Parathyroid disorders, especially hyperparathyroidism with imagings and their respective values are discussed. Methoxy isobutyl isonitrile (MIBI) scintigraphy with its high sensitivity and specificity for detecting parathyroid lesions is the modality of choice for the preoperative evaluation. Ultrasonography (US) and magnetic resonance imaging (MRI) also play important role for localizing and characterizing the lesions. The classical X-ray findings of hyperparathyroidism with pathologic correlations also are reviewed.

Magnetic resonance and computed tomography-based scoring system for the differential diagnosis of vertebral fractures caused by osteoporosis and malignant tumors.

BACKGROUND: Previous reports have described magnetic resonance imaging (MRI) findings alleged to be specific for vertebral fractures caused by malignant lesions. Using such findings for differential diagnosis is often difficult, especially during the early phase of the fracture. With the relative inaccuracy of any single imaging finding, a validated scoring system based on a combination of imaging findings might lead to enhanced diagnostic accuracy. The purpose of this study was to establish a diagnostic scoring system for discriminating osteoporotic vertebral fractures from those caused by malignant tumors on the basis of MRI and computed tomography (CT) findings. METHODS: Ten MRI and CT scan findings of 57 osteoporotic vertebral fractures and 43 neoplastic fractures were retrospectively evaluated for their ability to discriminate between malignant and benign vertebral fractures. RESULTS: The following four MRI and two CT findings were selected as the basis for the scoring system: pedicle or other posterior element involvement; extension into the paravertebral region; preservation of normal bone marrow signal; a continuous black line representing the posterior vertebral body margin on T2-weighted MRI images; osteolytic destruction; and distinct fracture lines on CT. CONCLUSION: By combining the findings common to MRI and CT scans of vertebral fractures, a simple scoring system was devised. This scoring system was found to enhance the accuracy of imaging diagnosis of fractures caused by benign or malignant spinal lesions.

Osteonecrosis of the femoral head in Japanese adults after liver transplantation: a preliminary report.

Patients who are treated with high-dose corticosteroids as an immunosuppressive therapy are at high risk of developing osteonecrosis, especially in the femoral head. We examined whether symptomatic osteonecrosis of the femoral head (ONFH) would be a clinical problem after liver transplantation. From June 1990 to December 2001, a total of 169 patients underwent liver transplantation at the Shinshu University Hospital. Within this group, 65 patients were more than 18 years old at the time of surgery, and all were enrolled in the present study. All patients were referred to the Orthopaedic Department of Shinshu University Hospital when they experienced musculoskeletal symptoms, including hip or groin pain. In addition, they were informed of the potential risk of osteonecrosis associated with immunosuppressive therapy after the liver transplant. As result, the patients were advised to have a magnetic resonance imaging (MRI) check for osteonecrosis after transplant surgery. In terms of outcomes, none of the patients presented with symptomatic hip difficulties due to osteonecrosis. Additional clinical investigation revealed that of the 18 patients who underwent MRI screening, only one was found to have asymptomatic unilateral ONFH. In conclusion, ONFH after liver transplantation has not been a clinical problem for our patients.