The findings of fluorodeoxyglucose F18 imaging of coincidence single photon emission computed tomography in the lung tuberculoma

Objective To assess the uptake of Fluorodeoxyglucose F18 (18F-FDG) coincidence single photon emission computed tomography (SPECT) imaging in lung tuberculoma. Methods We enrolled 27 cases with 29 tuberculomas confirmed by clinical diagnosis. 18F-FDG triple-head coincidence imaging was performed. The intensity of uptake was graded by visual method and the relationgship of the uptake and attenuation was analyzed. Results The uptake of 18F-FDG was graded by visual method. There were 10 lesions (34.5%) in grade 0, including 7 (24.1%) lesions that showed focal lack of uptake and 3(10.3%) lesions showed normal uptake in tomograph imaging. Eleven lesions (37.9%) were graded as 1-2, 5 lesions (17.2%) as 3, and 3 lesions as 4. With grade 0-2 being regarded as benign, the false positive rate was 8/29. The intensity of 18F-FDG uptake was divided into 3 groups (grade 0, grade 1-2, grade 3-4) and the intensity of uptake was compared with the attenuation of tuberculomas. There was a statistically significant difference among the 3 groups (χ2=13.29-18.02, P<0.01). Conclusions The intensity of 18F-FDG uptake was influenced by the attenuation of the lesion. Most lung tuberculomas for 18F-FDG coincidence imaging were of low uptake, and lower uptake than the background was a characteristic finding for tuberculoma.The combination with CT imaging was useful for the differentiation from malignant lesions. Key words: Tuberculoma; Fluorodeoxyglucose F18; Tomography, emission-computed