自身免疫性胰腺炎的^(18)F-FDGPET/CT显像特征

Imaging Features of ^(18)F-FDG PET/CT in Autoimmune Pancreatitis

目的探讨自身免疫性胰腺炎(autoimmune pancreatitis,AIP)的18氟-脱氧葡萄糖(18 F-fluorodeoxyglucose,18F-FDG)正电子发射断层扫描/计算机断层扫描(positron-emission tomography/computed tomography,PET/CT)的显像特征。方法回顾性分析14例经作者医院诊治的AIP患者的18F-FDG PET/CT资料,分析其胰腺局部及胰腺外器官的形态改变及代谢特征,并计算胰腺病变的平均滞留指数(retention index,RI),分析早期最大标准摄取值(maximum standardized uptake value,SUVmax)、延迟SUVmax之间的差异。结果 14例患者中,男5例,女9例,年龄31~67岁,平均年龄49岁。11例患者胰腺弥漫性肿大,3例患者胰腺头部增大,病变部位代谢活性均增高。10例患者的主胰管呈弥漫性狭窄,3例为局限性并多灶性狭窄,1例病变部位胰管局限性狭窄伴近端胰胆管扩张。5例患者出现胰腺周围鞘膜征;3例患者胰腺周围出现渗出。14例AIP患者胰腺早期SUVmax与延迟后SUVmax的差异有统计学意义(t=-6.63,P<0.05)。3例胰腺局灶性增大患者的早期SUVmax与延迟后SUVmax的差异无统计学意义(t=-4.5,P=0.05)。胰腺弥漫增大患者与胰腺局部肿大患者的早期SUVmax、延迟SUVmax、RI之间的差异无统计学意义(P>0.05)。14例AIP患者均出现胰腺外器官的改变;PET/CT的诊断正确率为71.4%(10/14),其中3例误诊为胰头癌,1例误诊为急性胰腺炎。结论 AIP的18F-FDG PET/CT显像有一定的特征性,了解其特征及其鉴别诊断特征,有助于提高该病的诊断正确率。

Objective To investigate the imaging features of 18F-fluorodeoxyglucose（18F-FDG）positron-emission tomography/computed tomography（PET/CT）in autoimmune pancreatitis（AIP）.Methods A total of 14 AIP patients’ 18F-FDG PET/CT data in authors’ hospital were retrospectively analyzed,the metabolic activity characteristics of the local pancreatic and extrapancreatic organs were analyzed,and average retention index（RI）of pancreatic lesions,early maximum standardized uptake value（SUVmax）,delayed SUVmax were calculated and compared.Results Among 14 patients（5 males and 9females）,the average age was 49 years（ranged,31-67 years）,11 patients with diffuse enlargement of pancreas,3 patients with local enlargement of the head of pancreas,the metabolic activity of the lesion site were increased.The main pancreatic duct in 10 patients showed diffuse stenosis,3 patients were localized and multifocal stenosis,1 patients was localized pancreatic duct stricture with proximal pancreatic obiliary dilatation,5 patients with peripancreatic sheath syndrome,3 patients with pancreatic leakage around.There were statistically significant difference in early SUVmax and the delayed SUVmax of 14 AIP patients（t=-6.63,P〈0.05）,and had no statistical difference between early SUVmax and delay SUVmax of 3local pancreatic growth patients（t=-4.5,P=0.05）.The difference among the early SUVmax,delayed SUVmax and RI were not statistically significant of patients with diffuse enlargement in pancreas（P〉0.05）.In 14 AIP patients,the changes of pancreatic external organs were found.The diagnostic accuracy of PET/CT was 71.40%（10/14）,among which 3 patients was misdiagnosed as pancreatic head carcinoma,and 1 patient were misdiagnosed as acute pancreatitis.Conclusion 18F-FDG PET/CT AIP imaging has certain characteristics,and it is helpful to improve the correct rate and the accuracy of the disease.