18F-FDGPET／CT与增强CT对自身免疫性胰腺炎影像特征显示效能的对照研究

Imaging characteristics of autoimmune pancreatitis： l8F-FDG PET/CT versus contrast enhanced CT

目的比较18F—FDGPET／CT与增强cT（CECT）两种成像方法对自身免疫性胰腺炎（AIP）主要影像特征的显示能力。方法通过回顾性分析31例经组织学或临床随访证实的AIP患者的18F-FDGPET／CT及CECT资料，比较18F—FDGPET／CT与CECT对AIP主要影像特征显示率，并采用Fisher精确概率法进行检验。结果18F—FDGPET／CT扫描与CECT扫描在AIP主胰管弥漫性狭窄或节段性狭窄伴上游扩张（9例比12例）、肝内外胆管受累（15例比17例）、胰周及腹膜后淋巴结受累（18例比25例）的显示率差异均无统计学意义（P值均〉0．05）；CECT的鞘膜征显示率明显高于PET／CT（9例比18例，P=0．01）；PET／CT可显示其他非上腹部胰腺外器官受累情况，而CECT局部扫描未能显示；PET／CT有28例表现为代谢增高，CECT有28例表现为延迟强化；在病灶受累范围和形态上CECT较PET／CT更多表现为局限型（16例比9例），但差异无统计学意义（P值均〉0．05）。PET／CT显示的20例弥漫型中CECT显示8例（40．0％）为局限型；CECT显示的16例局限型中，PET／CT显示8例（50．0％）为弥漫型。结论PET／CT与CECT在AIP病灶影像特征的显示方面各有优势，在临床工作中合理地选择及联合应用有助于对AIP的准确诊断及全身评估。

Objective To compare 18F-FDG PET/CT and contrast enhanced CT （CECT） for demonstrating imaging characteristics of autoimmune panereatitis （AIP）. Methods Both 18 F-FDG PET/CT and CECT imaging were collected on 31 AIP patients who were histopathologically proved or clinically proved by following up. The frequencies of demonstration of the main imaging features were compared between is F-FDG PET/CT and CECT by using the Fisher exact test. Results Of the 31 cases, diffuse irregular narrowing or segmental stricture accompanied with distal dilation of main pancreatic duct were shown in 9 cases of PET/CT and 12 cases of CECT, intraheptic and extrahepatic bile duct changes （ PET/CT vs CECT： 15 vs 17 ）, peripancreatic or retroperitoneal lymph nodes involvement （PET/CT vs CECT： 18 vs 25 ） were more frequently detected on CECT than on PET/CT, but there was no statistically significant difference （P 〉 0.05 ）. Capsule like rim （CECT vs PET/CT： 1 8 vs 9） were more frequently seen on CECT than on PET/CT with statistically significant difference （P =0.01 ）. PET/CT could also detect extrapancreatic lesions in other areas besides epigastric zone, but CECT could not. Twenty eight cases had high FDG uptaking in PET/CT, while delayed enhancement was observed in 28 cases. Focal shape of pancreatic enlargement （CECT vs PET/CT： 16 vs 9 ） were more frequently detected on CECT than on PET/CT without statistically significant difference （ P 〉 0.05 ）. Of the 20 cases demonstrating diffuse FDG uptaking, 8 cases （40.0%） represented as localized shape on CECT. Of the 16 cases demonstrating localized shape on CECT, 8 cases （50.0%） represented as diffuse type on PET/CT. Conclusions Both ISF-FDG PET/CT and CECT have their own advantages for demonstrating imaging characteristics of AlP, rational selection and combination may help to accurately diagnose AlP and assess systemic condition in clinical work.