Comparative study of semi-quantitative value based on different reference point in diagnosis of pulmonary lesions with 18F-FDG coincidence imaging / 中华核医学与分子影像杂志

ABSTRACT

Objective To explore the optimal semi-quantitative uptake ratio for differentiation between benign and malignant lung lesions with 18F-FDG coincidence imaging.Methods One hundred and thirty-seven patients (89 males,48 females,age range33-78 years) with lung diseases underwent 18 FFDG coincidence imaging.The maximum radioactivity counts of the lung lesions (T),normal chest wall soft tissues (NT1) and the contralateral lung tissue (NT2) were measured.The ratios of R1 (T/NT1) and R2(T/NT2) were calculated.The optimal threshold values of R1(cutoff)and R2(cutoff) were identified by ROC curve analysis.Using the optimal threshold,the sensitivity,specificity and accuracy were calculated.Results The optimal threshold values R1(cutoff)and R2(cutoff) were identified as 3.58 and 4.40.The sensitivity,specificity and accuracy were 90.0％(90/100),89.2％(33/37),89.8％(123/137) according to R1(cutoff) and 90.0％ (90/100),78.4％(29/37),86.9％(119/137) according to R2(cutoff) Conclusion Based on which the chest wall soft tissue is taken as a reference point,the optimal threshold value of T/NT1 is 3.58 in differentiation between benign and malignant lung lesions with 18F-FDG coincidence imaging.