18F-FDG PET/CT诊断肺孤立性肉芽肿性炎

目的 观察¹⁸F-FDG PET/CT诊断肺孤立性肉芽肿性炎的价值。方法 观察60例经病理学证实肺孤立性肉芽肿性炎患者的¹⁸F-FDG PET/CT早期和延迟显像,分析病灶CT征象并测量¹⁸F-FDG代谢参数,分别评价PET、CT及PET/CT诊断肺肉芽肿性炎的准确率。采用Spearman相关性分析评价早期最大标准摄取值（SUV_max）与病灶最大径的相关性。结果 60例中,22例（22/60,36.67%）病灶位于左肺,38例（38/60,63.33%）位于右肺;病灶最大径0.4~8.4 cm;14例（14/60,23.33%）病灶为圆形或类圆形,46例（46/60,76.67%）形态不规则;CT值为22.0~77.0 HU;43例（43/60,71.67%）病灶密度均匀;41例（41/60,68.33%）病灶可见"反3字"征或尖角征,6例（6/60,10.00%）出现刀切征,1例（1/60,1.67%）出现晕征;4例（4/60,6.67%）病灶内部出现空洞;6例（6/60,10.00%）见支气管充气征;26例（26/60,43.33%）病灶位于胸膜下,其中20例（20/26,76.92%）病灶与胸膜呈宽基底相连,包括3例（3/20,15.00%）见胸膜凹陷征。60例病灶的早期中位SUV_max为3.95（1.73,6.78）,低于延迟期的4.55（2.52,7.65）（P<0.05）;中位RI为12.22%（5.89%,24.70%）。病灶早期SUV_max与其最大径呈正相关（r=0.57,P<0.05）。¹⁸F-FDG PET/CT诊断肺肉芽肿性炎的准确率为91.67%（55/60）,高于单独PET（61.67%,37/60）或CT（78.33%,47/60）检查（P均<0.05）;CT准确率高于PET（P<0.05）。结论 肺孤立性肉芽肿性炎¹⁸F-FDG PET/CT表现具有一定特征性;¹⁸F-FDG PET/CT诊断准确率高于单一PET及CT。

18F-FDG PET/CT for diagnosis of solitary granulomatous inflammation in lung

Objective To observe the value of ¹⁸F-FDG PET/CT imaging for diagnosis of solitary granulomatous inflammation in lung. Methods Early and delayed ¹⁸F-FDG PET/CT imaging of 60 patients with pulmonary solitary granulomatosis confirmed by pathology were observed. CT manifestations of the lesions were analyzed, the metabolic parameters of ¹⁸F-FDG were measured, and the diagnostic accuracy of PET/CT, CT and PET for pulmonary solitary granulomatosis were evaluated, respectively. Spearman correlation analysis was used to explore the correlation between early maximum standard uptake value (SUV_max) and maximum diameter of the lesions. Results Among 60 cases of pulmonary solitary granulomatosis, the lesions, located in the left lung in 22 cases (22/60, 36.67%), while in the right lung in 38 cases (38/60, 63.33%). The maximum diameter of the lesions was 0.4-8.4 cm. Round or quasi-round lesions were found in 14 cases (14/60, 23.33%), while irregular shaped lesions were observed in 46 cases (46/60, 76.67%), with CT value of 22.0-77.0 HU. Homogeneous density lesion was detected in 43 cases (43/60, 71.67%), "inverted 3 sign" or sharp angle sign was observed in 41 cases (41/60, 68.33%), while knife cut sign and halo sign were noticed in 6 (6/60, 10.00%) and 1 case (1/60, 1.67%), and cavities inside the lesions and bronchial inflation were found in 4 (4/60, 6.67%) and 6 cases (6/60, 10.00%), respectively. Subpleural lesions were observed in 26 cases (26/60, 43.33%). Lesions connected with the pleura in a wide base in 20 cases (20/26, 76.92%), with pleural indentation in 3 cases (3/20, 15.00%). The median of the early SUV_max of 60 lesions was 3.95 (1.73, 6.78), lower than that of the delayed stage (4.55, P<0.05). The median RI of lesions was 12.22% (5.89%, 24.70%). There was a positive correlation between early SUV_max and the maximum diameter (r=0.57, P<0.05). The accuracy of ¹⁸F-FDG PET/CT in diagnosing pulmonary granulomatous inflammation was 91.67% (55/60), higher than that of PET (61.67%, 37/60) or CT (78.33%, 47/60) (both P<0.05), and of CT was higher than that of PET (P<0.05). Conclusion ¹⁸F-FDG PET/CT manifestations of solitary granulomatous inflammation in lung had certain characteristics. The diagnostic accuracy of PET/CT was higher than that of single PET or CT.