Experimental and clinical studies on differential diagnosis of bone diseases with nucleomedical procedures.

This report is a study of the differential diagnosis of bone diseases using nucleomedical procedures. Experimental and clinical studies on the accumulation of 201Tl and 67Ga in bone inflammation and bone tumors were performed. Also, the degree of deposition of 99mTc-phosphorous compounds represented as a color difference was evaluated for a differentiation between malignant and benign diseases of the spine and shoulder. Uptake of 201Tl in inflammation of the spine and in tumor of the pelvis of rabbits was very low, while that of 67Ga was high. Uptake of 67Ga decreased gradually with lapse of time after the onset of inflammation. These experimental results agreed with clinical studies. The detectability of malignant tumors with 201Tl was inferior to that with 99mTc-label and 67Ga, although osteolytic lesions were occasionally 201Tl-positive. In terms of color range, the difference was 2 or less in spines of normal subjects and 3 or more in the metastatic bone disease and compression fracture. This difference was not statistically significant. Since 67Ga scan was occasionally negative in compression fracture, a differentiation was considered to be possible in such a case. A combined study of bone imaging with 99mTc-phosphorous compound including color difference, 67Ga imaging, bone-marrow imaging and radiography are considered to be helpful for the differentiation.