Abstract:

Objective To explore the value of SPECT/CT image fusion analysis in differential diagnosis for benign or malignant lesions of  suspected bone metastasis. Methods A total of 187  patients to be excluded bone metastasis were selected. The patients firstly underwent conventional planar ^99mTc-Methylene diphosphonate (^99mTc-MDP) whole body bone imaging at first. For suspected bone metastasis, corresponding local bone radionuclide SPECT and CT were used. SPECT/CT image fusion was carried out to identify lesion quality. Some patients were followed up or received additional examination. The differences of the diagnesis of SPECT, CT, and SPECT/CT were analyzed. Results Among a total of 340 suspected lesions. SPECT/CT image fusion diagnosed 137 (40.3%) benign lesions and 172 (50.6%) malignant lesions. Only 31 (9.1%) lesions were suspected. SPECT/CT had significant differences with single SPECT or CT (P<0.01 or 0.05). In 32 patients with definite diagnose, the diagnostic sensitivity, specificity, accuracy rate, and misdiagnosis rate were 93.8% (15/16), 87.5% (14/16), 90.6% (19/32), and 9.4% (3/32), respectively. Conclusion SPECT/CT image fusion analysis has high value in qualitative or differential diagnosis of suspected bone metastasis. However, comprehensive analysis is still need in order to reduce misdiagnosis.

Key words: single photon emission computed tomography/computed tomography, image fusion, bone imaging, bone metastasis