The Value And Application Of PET/CT In Diagnosing Pulmonary

ObjectiveThe objective of this work was to evaluate the efficacy of whole-body ¹⁸F-FDG PET/CT in diagnosing pulmonary occupying lesion,and describe PVE's consequences in SUV.Size-threshold was used to diagnose the different size lesions,which was help for increasing diagnosis accuracy of PET/CT.Patients with the lesions difficult to diagnose Undergone delay PET scans.Comparing with pathologic and follow-up findings,the value of delay scan was assessed.MethodsThis study included three parts.The value of 18F-FDG PET/CT in diagnosing pulmonary occupying lesion was evaluated in the first part.Patient studies:one hundred patients who had 18F-FDG PET/CT scans were retrospectively analyzed.SUVs in the ROI were measured.According to pathologic and follow-up findings,the efficacy of PET/CT, PET and CT;the SUVs of different size tumor;the SUVs of different pathologic tumor were compared respectively.In the second part,Model No.76-823 was used for this part.The influence of PVE to SUV was described.Mathematics method was used for correcting SUVs.One hundred fourteen patients with pulmonary occupying lesions undergo 18F-FDG PET/CT scans. According to the size,tumors were divided to five groups:＜2cm group,≥2cm and＜3cm group,≥3cm and＜4cm group,≥4cm and＜5cm group,and＞5cm group.The mean SUV of each group was calculated and was compared among different groups.According to the size,the benign lesions were divided to three groups:≥1cm and＜2cm group,≥2cm and＜3cm group,≥2cm and＜3cm group.The SUVs of different groups were compared.Size-threshold was used to differentiate malignant from benign lesion.The diagnosis validity of SUV 2.5 threshold and size-threshold were compared.Patients with the lesions difficult to diagnose undergo delay PET scans.Comparing with pathologic and follow-up findings,the value of delay imaging was assessed.ResultsOne hundred patients who had 18F-FDG PET/CT scans were retrospectively analyzed. The diagnosis sensitivity of PET/CT was 97.5%,specificity was 80.0%,accuracy was 94.0%.There was no difference between the SUV of squamous cell carcinoma and adencarcinoma.Model No.76-823 was used to PET/CT imaging.The size of rotundum had logarithm correlation with the radioactive counting.One hundred fourteen patients with pulmonary occupying lesions undergo 18F-FDG PET/CT scans.Significant deviation of SUV was found between the different size lesions.The diagnosis specificity and accuracy of size-threshold were higher than that of SUV 2.5 threshold(P＜0.05).Thirty-three patients with the lesions difficult to diagnose undergo delay PET scans.The SUVs of the lesions in twenty-three known cancer patients increased in eighteen lesions,decreased in three lesions and were stable in two lesions.The SUVs of thirteen benign lesions increased in nigh lesions,decreased in three lesions and was stable in one lesion.The delaying 180mins SUVs of thirteen benign lesions decreased in one inflaming nodule and four tuberculosis granulomas;increased in two pulmonary abscesses,three tuberculosis granulomas and one inflaming nodule.The SUVs of two inflaming nodule were stable.ConclusionThese preliminary data show that PET/CT imaging appears to be useful in diagnosing pulmonary occupying lesion.The using of size-threshold induced influence of PVE and enhanced diagnosis validity.Positive result of pulmonary abscess and tuberculosis granuloma should be pay attention.