The Clinical Value Of ⁹⁹Tc^m-MDP SPECT/CT In Skull And Vertebrae Diseases

Objective Axial bones are the most important parts of the body. The aim of this study was to evaluate the clinical value of 99Tcm-methylene diphosphonate(99m Tc-MDP) single photon emission computed tomography and X-ray computed tomography(SPECT/ CT) in axial bone diseases.Methods 57 patients with suspected abnormal radioactive uptake in99mTc-MDP whole body imaging were observed retrospectively. 65 osseous metastasis in axial bone were determined by follow up, pathology and other imaging modalities. Axial bone were examined by SPECT/CT scan right after 99 m Tc-MDP whole body imaging. The image characters of metastasis,hyperostosis and other abnormal radioactive uptake in head and spine were summarized. The diagnose accordance rates of SPECT, CT and SPECT/CT in axial bone metastasis were calculated and compared.Results For all the 57 patients, 99 m Tc-MDP SPECT had found 95 abnormal radioactive uptake foci and only 65 of them were identified osseous metastasis through the “Gold Standard” like pathology and long-term follow-up. The other 30 foci were diagnosed cervical vertebrae hyperostosis,accessory nasal cavity, mastoid air cell, dental necrosis, thyroid and geisoma non-specific radioactive uptake by SPECT/CT. The diagnose agreement rates of SPECT, CT and SPECT/CT in axial bone metastasis are 77.89%(74/95) ? 65.26%(62/95) and 94.74%(90/95); the sensitivity of three are80.00%?61.54%?95.39%; the specificity are 70.00%?73.33%?93.33%; the positive predictive value are 85.48% ? 88.33% ? 96.88%; the negative predictive value are 63.64%?46.81%?90.32%.Conclusion SPECT/CT in axial bone could not only provide accurate anatomic localization of the abnormal radioactive uptake, but also discriminate benign from malignant by displaying characters such as bone destruction, hyperostosis and formation of soft tissue boss. Great value can be get in differentiating osseous metastasis from hyperostosis and non-specific radioactive uptake. The methods of SPECT/CT imaging will be a good choice to diagnose axial bone diseases.