High-grade pancreatic intraepithelial neoplasia diagnosed based on changes in magnetic resonance cholangiopancreatography findings:A case report

BACKGROUND High-grade pancreatic intraepithelial neoplasia(PanIN)exhibits no mass and is not detected by any examination modalities.However,it can be diagnosed by pancreatic juice cytology from indirect findings.Most previous cases were diagnosed based on findings of a focal stricture of the main pancreatic duct(MPD)and caudal MPD dilatation and subsequent pancreatic juice cytology using endoscopic retrograde cholangiopancreatography(ERCP).We experienced a case of high-grade PanIN with an unclear MPD over a 20-mm range,but without caudal MPD dilatation on magnetic resonance cholangiopancreatography(MRCP).CASE SUMMARY A 60-year-old female patient underwent computed tomography for a follow-up of uterine cancer post-excision,which revealed pancreatic cysts.MRCP revealed an unclear MPD of the pancreatic body at a 20-mm length without caudal MPD dilatation.Thus,course observation was performed.After 24 mo,MRCP revealed an increased caudal MPD caliber and a larger pancreatic cyst.We performed ERCP and detected atypical cells suspected of adenocarcinoma by serial pancreatic juice aspiration cytology examination.We performed a distal pancreatectomy and obtained a histopathological diagnosis of high-grade PanIN.Pancreatic parenchyma invasion was not observed,and curative resection was achieved.CONCLUSION High-grade Pan-IN may cause MPD narrowing in a long range without caudal MPD dilatation.

Advancements of molecular imaging and radiomics in pancreatic carcinoma

Despite the recent progress of medical technology in the diagnosis and treatment of tumors,pancreatic carcinoma remains one of the most malignant tumors,with extremely poor prognosis partly due to the difficulty in early and accurate imaging evaluation.This paper focuses on the research progress of magnetic resonance imaging,nuclear medicine molecular imaging and radiomics in the diagnosis of pancreatic carcinoma.We also briefly described the achievements of our team in this field,to facilitate future research and explore new technologies to optimize diagnosis of pancreatic carcinoma.

Pancreatic carcinoma coexisting with chronic pancreatitis versus tumor-forming pancreatitis:Diagnostic utility of the time-signal intensity curve from dynamic contrast-enhanced MR imaging

AIM: To evaluate the ability of the time-signal intensity curve (TIC) of the pancreas obtained from dynamic contrast-enhanced magnetic resonance imaging (MRI) for differentiation of focal pancreatic masses, especially pancreatic carcinoma coexisting with chronic pancreatitis and tumor-forming pancreatitis. METHODS: Forty-eight consecutive patients who underwent surgery for a focal pancreatic mass, including pancreatic ductal carcinoma (n = 33), tumor-forming pancreatitis (n = 8), and islet cell tumor (n = 7), were reviewed. Five pancreatic carcinomas coexisted with longstanding chronic pancreatitis. The pancreatic TICs were obtained from the pancreatic mass and the pancreatic parenchyma both proximal and distal to the mass lesion in each patient, prior to surgery, and were classified into 4 types according to the time to a peak: 25 s and 1, 2, and 3 min after the bolus injection of contrast material, namely, type-Ⅰ, Ⅱ, Ⅲ, and Ⅳ, respectively, and were then compared to the corresponding histological pancreatic conditions. RESULTS: Pancreatic carcinomas demonstrated type-Ⅲ (n = 13) or Ⅳ (n = 20) TIC. Tumor-forming pancreatitis showed type-Ⅱ (n = 5) or Ⅲ (n = 3) TIC. All islet cell tumors revealed type-Ⅰ. The type-Ⅳ TIC was only recognized in pancreatic carcinoma, and the TIC of carcinoma always depicted the slowest rise to a peak among the 3 pancreatic TICs measured in each patient, even in patients with chronic pancreatitis.CONCLUSION: Pancreatic TIC from dynamic MRI provides reliable information for distinguishing pancreatic carcinoma from other pancreatic masses, and may enable us to avoid unnecessary pancreatic surgery and delays in making a correct diagnosis of pancreatic carcinoma, especially, in patients with longstanding chronic pancreatitis.

CT and MR imaging patterns for pancreatic carcinoma invading the extrapancreatic neural plexus (Part Ⅱ):Imaging of pancreatic carcinoma nerve invasion

Computed tomography (CT) and magnetic resonance imaging (MRI) are excellent modalities which have the ability to detect,depict and stage the nerve invasion associated with pancreatic carcinoma.The aim of this article is to review the CT and MR patterns of pancreatic carcinoma invading the extrapancreatic neural plexus and thus provide useful information which could help the choice of treatment methods.Pancreatic carcinoma is a common malignant neoplasm with a high mortality rate.There are many factors influencing the prognosis and treatment options for those patients suffering from pancreatic carcinoma,such as lymphatic metastasis,adjacent organs or tissue invasion,etc.Among these factors,extrapancreatic neural plexus invasion is recognized as an important factor when considering the management of the patients.

Application and progress of medical imaging in total mesopancreas excision for pancreatic head carcinoma

Pancreatic head carcinoma(PHC)is one of the common gastrointestinal malignancies with a high morbidity and poor prognosis.At present,radical surgery is still the curative treatment for PHC.However,in clinical practice,the actual R0 resection rate,the local recurrence rate,and the prognosis of PHC are unsatisfactory.Therefore,the concept of total mesopancreas excision(TMpE)is proposed to achieve R0 resection.Although there have various controversies and discussions on the definition,the range of excision,and clinical prognosis of TMpE,the concept of TMpE can effectively increase the R0 resection rate,reduce the local recurrence rate,and improve the prognosis of PHC.Imaging is of importance in preoperative examination for PHC;however,traditional imaging assessment of PHC does not focus on mesopancreas.This review discusses the application of medical imaging in TMpE for PHC,to provide more accurate preoperative evaluation,range of excision,and more valuable postoperative follow-up evaluation for TMpE through imaging.It is believed that with further extensive research and exploratory application of TMpE for PHC,large-sample and multicenter studies will be realized,thus providing reliable evidence for imaging evaluation.

Prognostication and response assessment in liver and pancreatic tumors:The new imaging

Diffusion-weighted imaging(DWI), dynamic contrastenhanced magnetic resonance imaging(DCE-MRI) and perfusion computed tomography(CT) are technical improvements of morphologic imaging that can evaluate functional properties of hepato-bilio-pancreatic tumors during conventional MRI or CT examinations.Nevertheless, the term "functional imaging" is commonly used to describe molecular imaging techniques, as positron emission tomography(PET)CT/MRI, which still represent the most widely used methods for the evaluation of functional properties of solid neoplasms; unlike PET or single photon emission computed tomography, functional imaging techniques applied to conventional MRI/CT examinations do not require the administration of radiolabeled drugs or specific equipments. Moreover, DWI and DCE-MRI can be performed during the same session, thus providing a comprehensive "one-step" morphological and functional evaluation of hepato-bilio-pancreatic tumors. Literature data reveal that functional imaging techniques could be proposed for the evaluation of these tumors before treatment, given that they may improve staging and predict prognosis or clinical outcome. Microscopic changes within neoplastic tissues induced by treatments can be detected and quantified with functional imaging,therefore these techniques could be used also for posttreatment assessment, even at an early stage. The aim of this editorial is to describe possible applications of new functional imaging techniques apart frommolecular imaging to hepatic and pancreatic tumors through a review of up-to-date literature data, with a particular emphasis on pathological correlations,prognostic stratification and post-treatment monitoring.

MR dynamic Gadolinium-enhanced fast multiplanar spoiled gradient-echo and spin-echo T1-weighted fat-suppressed techniques in diagnosis of pancreatic carcinoma

Objective: To evaluate the value of MR dynamic Gadolinium-enhanced fast multiplanar spoiled gradi- ent-echo (FMPSPGR) and spin-echo (SE) T1- weighted fat-suppressed techniques in the diagnosis of pancreatic carcinoma. Methods: Eighteen cases of pancreatic carcinoma veri- fied by surgical and pathologic results were examined by MR, and the MR sequences included SE T1WI, FSE T2WI, SE T1-weighted fat-suppressed and dy- namic Gadolinium-enhanced FMPSPGR. Results: Of 18 pancreatic carcinomas, 10, 6, and 2 tumors showed respectively hypo-intensity, iso-inten- sity and hyper-intensity on SE T1WI, meanwhile, 8, 6, and 4 tumors displayed hyper-intensity, iso-inten- sity and hypo-intensity on FSE T2WI in comparison with the normal pancreatic tissue. All of the tumors showed hypo-intensity on SE T1-weighted fat-sup- pressed and also obvious non-enhancement or slight enhancement on MR dynamic Gadolinium-enhanced FMPSPGR images during the arterial dominant phase scanning. Conclusion: SE T1-weighted fat-suppressed and MR dynamic Gadolinium-enhanced FMPSPGR sequences could evidently improve the sensitivity and specificity in the diagnosis of pancreatic carcinoma.

Focal autoimmune pancreatitis: Radiological characteristics help to distinguish from pancreatic cancer

AIM: To identify the radiological characteristics of focal autoimmune pancreatitis (f-AIP) useful for differentiation from pancreatic cancer (PC). METHODS: Magnetic resonance imaging (MRI) and triple-phase computed tomography (CT) scans of 79 patients (19 with f-AIP, 30 with PC, and 30 with a normal pancreas) were evaluated retrospectively. A radiologist measured the CT attenuation of the pancreatic parenchyma, the f-AIP and PC lesions in triple phases. The mean CT attenuation values of the f-AIP lesions were compared with those of PC, and the mean CT attenuation values of pancreatic parenchyma in the three groups were compared. The diagnostic performance of CT attenuation changes from arterial phase to hepatic phase in the differentiation between f-AIP and PC was evaluated using receiver operating characteristic (ROC) curve analysis. We also investigated the incidence of previously reported radiological findings for differentiation between f-AIP and PC. RESULTS: The mean CT attenuation values of f-AIP lesions in enhanced phases were significantly higher than those of PC (arterial phase: 60 ± 7 vs 48 ± 10, P < 0.05; pancreatic phase: 85 ± 6 vs 63 ± 15, P < 0.05; hepatic phase: 95 ± 7 vs 63 ± 13, P < 0.05). The mean CT attenuation values of f-AIP lesions were significantly lower those of uninvolved pancreas and normal pancreas in the arterial and pancreatic phase of CT (P < 0.001, P < 0.001), with no significant difference at the hepatic phase or unenhanced scanning (P = 0.4, P = 0.1). When the attenuation value increase was equal or more than 28 HU this was considered diagnostic for f-AIP, and a sensitivity of 87.5%, specificity of 100% and an area under the ROC curve of 0.974 (95%CI: 0.928-1.021) were achieved. Five findings were more frequently observed in f-AIP patients: (1) sausageshaped enlargement; (2) delayed homogeneous enhancement; (3) hypoattenuating capsule-like rim; (4) irregular narrowing of the main pancreatic duct (MPD) and/or stricture of the common bile duct (CBD); and (5) MPD upstream dilation ≤ 5 mm. CONCLUSION: Analysis of a combination of CT and MRI findings could improve the diagnostic accuracy of differentiating f-AIP from PC.

Quantification of pancreatic exocrine function of chronic pancreatitis with secretin-enhanced MRCP

AIM:To obtain reference values for pancreatic flow output rate(PFR)and peak time(PT)in healthy volunteers and chronic pancreatitis(CP);to correlate quantification of secretin enhanced magnetic resonance cholangiopancreatography(SMRCP)of pancreatic fluid output following secretin with fecal elastase-1(FE-1)tests.METHODS:The present study includes 53 subjects comprised of 17 healthy individuals and 36 patients with CP from April 2011 to January 2013.The 36 patients with CP were divided into three groups of mild CP(n=14),moderate CP(n=19)and advanced CP(n=3)by M-ANNHEIM classification for CP..Fifty-three cases underwent FE-1 test and magnetic resonance imaging using 3.0 T-device(Signa EXCITE,GE Healthcare).Coronal T2-weighted single-shot turbo spin-echo,spiratory triggered,covering the papillae,duodenum and small bowel.MRCP was performed with a heavily T2-weighted fat-suppressed long TE HASTE sequence (thick slab 2D MRCP sequence),repeated every 2 min up to 11 min after 0.1 mL/kg secretin injection(Secrelux,Sanochemia,Germany).FE-1 test used sandwich enzyme-linked immunosorbent assay(ELISA)test(ScheBo.Tech,Germany).RESULTS:A good linear correlation showed between the calculated volume and the actual volume by Phantom experiments.Fifty-three paired Quantification of secretin enhanced magnetic resonance cholangiopancreatography(MRCPQ)and FE-1 data sets were analyzed.The mean FE-1 of 53 cases was 525.41±94.44μg/g for 17 healthy volunteers,464.95±136.13μg/g for mild CP,301.55±181.55μg/g for moderate CP,229.30±146.60μg/g for advanced CP.Also,there was statistically significant difference in FE-1(P=0.0001)between health and CP.The mean values of PFR and PT were 8.18±1.11 mL/min,5.76±1.71 min for normal;7.27±2.04 mL/min,7.71±2.55 min for mild CP;4.98±2.57 mL/min,9.10±3.00 min for moderate CP;4.13±1.83 mL/min,12.33±1.55 min for advanced CP.Further,statistically significant difference in PFR(P=0.0001)and PT(P=0.0001)was observed between health and CP.Besides,there was correlation(r=0.79)and consistency(K=0.6)between MRCPQ and ELISA Test.It was related between M-ANNHEIM classification and PFR(r=0.55),FE-1(r=0.57).CONCLUSION:SMRCP can provide a safe,non-invasive and efficient method to evaluate the exocrine function of the pancreas.

Blunt pancreatic trauma: A persistent diagnostic conundrum?

Blunt pancreatic trauma is an uncommon injury but has high morbidity and mortality. In modern era of trauma care, pancreatic trauma remains a persistent challenge to radiologists and surgeons alike. Early detection of pancreatic trauma is essential to prevent subsequent complications. However early pancreatic injury is often subtle on computed tomography(CT) and can be missed unless specifically looked for. Signs of pancreatic injury on CT include laceration, transection, bulky pancreas, heterogeneous enhancement, peripancreatic fluid and signs of pancreatitis. Pan-creatic ductal injury is a vital decision-making parameter as ductal injury is an indication for laparotomy. While lacerations involving more than half of pancreatic parenchyma are suggestive of ductal injury on CT, ductal injuries can be directly assessed on magnetic resonance imaging(MRI) or encoscopic retrograde cholangio-pancreatography. Pancreatic trauma also shows temporal evolution with increase in extent of injury with time. Hence early CT scans may underestimate the extent of injures and sequential imaging with CT or MRI is important in pancreatic trauma. Sequential imaging is also needed for successful nonoperative management of pancreatic injury. Accurate early detection on initial CT and adopting a multimodality and sequential imaging strategy can improve outcome in pancreatic trauma.

Pancreatitis in patients with pancreas divisum:Imaging features at MRI and MRCP

AIM:To determine the magnetic resonance cholangiopancreatography(MRCP)and magnetic resonance imaging(MRI)features of pancreatitis with pancreas divisum(PD)and the differences vs pancreatitis without divisum.METHODS:Institutional review board approval was obtained and the informed consent requirement was waived for this HIPAA-compliant study.During one year period,1439 consecutive patients underwent successful MRCP without injection of secretin and abdominal MRI studies for a variety of clinical indications using a 1.5 T magnetic resonance scanner.Two experienced radiologists retrospectively reviewed all the studies in consensus.Disputes were resolved via consultation with a third experienced radiologist.The assessment included presence and the imaging findings of PD,pancreatitis,and distribution of abnormalities.The pancreatitis with divisum constituted the study group while the pancreatitis without divisum served as the control group.MRCP and MRI findings were correlated with final diagnosis.Fisher exact tests and Pearson × 2 tests were performed.RESULTS:Pancreatitis was demonstrated at MRCP and MRI in 173 cases(38 cases with and 135 cases without divisum)among the 1439 consecutive cases.The recurrent acute pancreatitis accounted for 55.26%(21 of 38)in pancreatitis patients associated with PD,which was higher than 6.67%(9 of 135)in the control group,whereas the chronic pancreatitis was a dominant type in the control group(85.19%,115 of 135)when compared to the study group(42.11%,16 of 38)(χ 2 = 40.494,P < 0.0001).In cases of pancreatitis with PD,the dorsal pancreatitis accounted for a much higher percentage than that in pancreatitis without PD(17 of 38,44.74% vs 30 of 135,22.22%)(χ 2 = 7.257,P < 0.05).CONCLUSION:MRCP and MRI can depict the features of pancreatitis associated with divisum.Recurrent acute pancreatitis and isolated dorsal involvement are more common in patients with divisum.

Duodenal duplication cyst causing severe pancreatitis:Imaging findings and pathological correlation

We here report a case of a 18-year-old man with a history of recurrent abdominal pain and a previous episode of severe acute pancreatitis. Abdominal ultrasonography, contrast enhanced multislice computer tomography, endoscopic retrograde cholangiopancreatography, endoscopic ultrasonography and magnetic resonance imaging demonstrated a cystic mass lesion. Only on delayed phase magnetic resonance images after GadoliniumBOPTA injection, it was possible to demonstrate the lesion's relationship with the biliary tree, differentiating the lesion from intraluminal duodenal diverticulum, and to achieve the diagnosis of duodenal duplication cyst, a recognized rare cause of acute pancreatitis. The diagnosis was confirmed by histology.

Ansa pancreatica as a predisposing factor for recurrent acute pancreatitis

AIM To determine the non-biased prevalence and clinical significance of ansa pancreatica in patients with acute pancreatitis using magnetic resonance imaging(MRI).METHODS Our institutional review board approved this crosssectional study, which consisted of a community-based cohort of 587 consecutive participants in a whole-body health-check program, and 73 subjects with episode of acute pancreatitis(55 patients with a single episode of acute pancreatitis, and 18 patients with recurrent acute pancreatitis). All of the subjects underwent abdominal MRI including magnetic resonance cholangiopancreatography, medical examinations, and blood tests. Two board-certified, diagnostic, abdominal radiologists evaluated the images, and ansa pancreatica was diagnosed based on its characteristic anatomy on MRI.RESULTS Compared with the community group [5/587(0.85%)], patients with recurrent acute pancreatitis had a significantly higher frequency of ansa pancreatica [2/18(11.1%)](P = 0.016; OR = 14.3; 95%CI: 1.27-96.1), but not compared with patients with single-episode acute pancreatitis [1/55(1.8%)](P = 0.42; OR = 2.1; 95%CI: 0.44-19.7). Multiple logistic regression analysis using age, alcohol intake, presence of ansa pancreatica, and presence of autoimmune disease as independent covariates, revealed a significant relationship between the presence of ansa pancreatica and recurrent acute pancreatitis. The presence of autoimmune disease was also significantly associated with the onset of recurrent acute pancreatitis. On the other hand, neither age nor alcohol intake were significantly related to the onset of recurrent acute pancreatitis.CONCLUSION The present study is the first to provide robust evidence that the presence of ansa pancreatica is significantly associated with recurrent acute pancreatitis.

采用磁共振2D-MRCP电影成像无创评估胰腺外分泌功能的可行性研究

目的探讨采用二维磁共振胰胆管成像(two-dimensional magnetic resonance cholangiopancreatography,2D-MRCP)动态电影成像序列定量检测健康志愿者摄入脂餐后主胰管内生理胰液分泌变化的可行性。材料与方法招募健康志愿者36人,所有志愿者均行2D-MRCP电影序列扫描,每个电影序列选择胰头层面,在胰头位置施加宽度为20 mm的空间选择反转脉冲(inversion pulse,IR)饱和带,单层屏气扫描,屏气时长为5 s,屏气间隔为15 s,脂餐前屏气20次采集并测量该志愿者胰液分泌的频率和长度(基础状态的频率和长度),脂餐后屏气60次,观察脂餐后胰液分泌的动态变化。采用配对t检验比较脂餐前后胰液分泌长度的变化,并比较脂餐后胰液分泌频率较基础频率增加百分比。根据年龄将志愿者分为三组,第一组年龄≤30岁,第二组年龄>30岁并≤60岁,第三组年龄>60岁,采用Kruskal-Wallis法比较脂餐后胰液分泌平均频率、平均长度与年龄之间的关系。结果脂餐前胰液分泌的频率为21.32%±1.20%,脂餐后胰液分泌的频率为29.82%±1.11%,频率增加了8.50%,差异具有统计学意义(P<0.001);脂餐前胰液分泌的长度为(11.06±7.27)mm,脂餐后胰液分泌的长度为(15.34±4.61)mm,长度平均增加了4.28 mm,差异具有统计学意义(P<0.05)。第一组与第二、三组之间胰液平均频率和长度差异均具有统计学意义(P<0.001);第二组与第三组之间胰液平均频率和长度差异均无统计学意义(P=0.477,P=0.316)。结论2D-MRCP动态电影序列可定量检测脂餐后胰液分泌流量变化,该序列对无创评估生理状态下胰腺外分泌功能具有临床价值。脂餐后胰液分泌功能随着年龄的增长可能呈下降趋势。

Value of diffusion-weighted imaging in distinguishing pancreatic carcinoma from mass-forming chronic pancreatitis： a meta-analysis

Background Several previous studies have shown that diffusion-weighted imaging （DWl） can provide additional information for focal pancreatic lesions by demonstrating more restricted diffusion in solid malignant tumors than in chronic pancreatitis, which can be indicated by a decreased apparent diffusion coefficient （ADC）. However, these studies have a modest sample size and convey inconclusive results. The aim of this study was to determine, in a meta-analysis, the diagnostic performance of quantitative diffusion-weighted magnetic resonance imaging in distinguishing pancreatic carcinoma from mass-forming chronic pancreatitis. Methods We determined the sensitivities and specificities across studies. A summary receiver operator characteristic （sROC） curve was constructed to calculate the area under the curve （AUC）. Results The pooled sensitivity of DWI was 0.86 （95% Cl： 0.80-0.91） and the pooled specificity was 0.82 （95% CI： 0.72- 0.89）. The AUC of the sROC was 0.91 （95% CI： 0.88-0.93）. Conclusions DWl may be a potentially technically feasible tool for differentiating pancreatic carcinoma from mass- forming chronic pancreatitis. However, large-scale randomized control trials are necessary to assess its clinical value.

胰腺腺泡细胞癌的增强MRI和DWI特征

目的探讨胰腺腺泡细胞癌(PACC)的增强MRI和DWI特征。方法选取并分析经病理证实的14例PACC患者的病例资料,分析患者的肿瘤位置、形状、大小、边界、有无囊变坏死、囊实性交界面是否清晰、有无出血、胰管有无扩张、MRI信号特点及强化方式、有无转移、有无周围组织受累及淋巴结肿大等情况,测量肿瘤实质及其周围正常胰腺组织的ADC值,并进行统计学分析。结果14例患者肿瘤均为单发,肿瘤范围1.9~14.0cm,最大径(5.1±3.0)cm,7例位于胰头部,7例位于胰体尾部,11例呈类圆形,10例病灶边缘清晰,8例出现不同程度囊变坏死,囊变坏死范围5例<30.0%,2例30.0%~70.0%,1例>70.0%,2例出血,8例出现胰管扩张与胰腺萎缩,肿瘤实质13例T_(1)WI呈低或稍低信号,10例T_(2)WI呈稍高或高信号,14例DWI均呈高信号,ADC图均呈低信号,12例呈轻度渐进性强化,2例呈轻中度持续强化,各期强化程度均低于正常胰腺组织,9例出现周围组织受累,7例发生肝脏和(或)淋巴结转移,肿瘤实质的平均ADC值为(1.033±0.247)×10^(-3)mm^(2)/s,周围正常胰腺组织的平均ADC值为(1.807±0.434)×10^(-3)mm^(2)/s,两者差异有统计学意义(t=-7.518,P<0.001)。结论PACC在MRI具有一定的特征性。

MRI、MRCP对原发性胆囊癌的诊断价值

目的探讨原发性胆囊癌及其浸润转移的MRI、MRCP表现,评价MRI结合MRCP对原发性胆囊癌的诊断价值。资料与方法胆囊癌患者34例,均行MRI扫描,包括轴位、冠状位T1WI、T2WI平扫,MRCP;10例行轴位、冠状位增强扫描;7例行脂肪抑制扫描。结果所有胆囊癌原发灶均为MRI显示,其诊断分型符合率为85.7%;对肝脏直接浸润的诊断正确性为78.6%,肝脏转移的诊断正确性为89.3%,淋巴结转移的敏感性为66.7%,诊断正确性为85.8%;对胆管受侵阳性诊断率为100%,诊断准确性为82.1%。结论MRI与MRCP联合应用,能较为准确地对原发性胆囊癌进行诊断和分型,并能准确地描述和评价胆囊癌扩散程度及浸润范围。

原发性胆囊癌的CT、MRI诊断价值

目的:探讨胆囊癌的CT、磁共振成像(MRI)表现,提高胆囊癌的影像诊断水平。方法:回顾性分析30例经手术病理证实为胆囊癌的CT、MRI影像学资料,其中28例行CT检查,14例行MRI检查。分析原发病灶的直接征象和间接征象,并与大体病理进行对照。结果:胆囊壁不规则增厚、胆囊腔内结节和(或)胆囊区肿块为胆囊癌的直接征象,其中厚壁型11例,腔内型10例,肿块型9例;增强检查后,增厚的胆囊壁、结节和(或)肿块明显持续强化。其他表现包括合并胆囊结石23例,肝内外胆管扩张13例,肝脏直接受侵11例,累及胃和十二指肠者分别为3例和5例,淋巴结转移16例,肝脏转移3例。上述征象MRI均能显示,4例肿大淋巴结于CT上难以判断,3例等密度胆囊结石于CT上未检出。结论:CT及MRI能清楚地显示胆囊癌的原发灶,并能较准确地评价胆囊癌浸润程度及扩散范围,且MRI对胆囊结石、区域淋巴结转移等间接征象的显示要优于CT。

IVIM-DWI在胰腺癌和神经内分泌肿瘤诊断和鉴别中的应用价值

目的:探讨IVIM-DWI诊断和鉴别胰腺癌和胰腺神经内分泌肿瘤的最佳量化参数。材料与方法:应用GE Discovery MR750 3.0T磁共振扫描仪对手术证实的22例胰腺癌和17例胰腺神经内分泌肿瘤患者行胰腺多b值DWI。应用IVIM双指数模型测量胰腺癌和胰腺神经内分泌肿瘤与非瘤区胰腺组织的表观扩散系数(ADC)、纯扩散系数(D)、假扩散系数(D~*)和灌注分数(f),并应用单因素方差分析进行统计学分析。结果:胰腺癌的ADC和f低于非癌区胰腺组织(0.803×10^(-3)mm^2/s vs0.974×10^(-3)mm^2/s:54.527%vs 64.486%),D高于非癌区胰腺组织(0.659×10^(-3)mm^2/s vs 0.535×10^(-3)mm^2/s),鉴别胰腺癌和非癌区胰腺组织时D诊断效能最高。胰腺神经内分泌肿瘤的ADC、D和f均高于非瘤区胰腺组织(0.933×10^(-3)mm^2/s vs 0.753×10^(-3)mm^2/s;0.549×10^(-3)mm^2/s vs 0.429×10^(-3)mm^2/s:67.275%vs 59.655%).鉴别胰腺神经内分泌肿瘤和非瘤区胰腺组织时ADC诊断效能最高。胰腺癌的ADC、D~*和f低于胰腺神经内分泌肿瘤(0.803×10^(-3)mm^2/s vs 0.933×10^(-3)mm^2/s;4.852×10^(-3)mm^2/s vs 11.301×10^(-3)mm^2/s;54.527%vs 67.275%),鉴别胰腺癌和神经内分泌肿瘤是D~*诊断效能最高。胰腺癌的D~*明显低于G2~3期胰腺神经内分泌肿瘤(4 852×10^(-3)mm^2/s vs 11.937×10^(-3)mm^2/s)。结论:IVIM-DWI相关参数(ADC、D~*、D、f)可以有效鉴别胰腺癌和胰腺神经内分泌肿瘤与非瘤区胰腺组织.IVIM-DWI是无创性诊断和鉴别胰腺癌和胰腺神经内分泌肿瘤的理想方法之一。

磁共振扩散加权成像在胰腺癌诊断中的价值

目的探讨磁共振扩散加权成像(DWI)及相应的表观扩散系数(ADC)在胰腺癌诊断中的价值。方法正常对照组25例,临床及影像学证实的急性胰腺炎患者26例,经手术病理证实或临床随访证实胰腺癌患者23例,在上腹部常规序列扫描后行DWI成像。比较T1WI、T2WI及DWI序列上癌组织相对于癌周组织的信号强度比(signal intensity ratio,SIR);b=500s/mm2时,分别测量感兴趣区的ADC值,比较胰腺癌组织、癌周组织、急性胰腺炎患者胰腺组织及正常对照组胰腺组织的ADC值并进行统计学分析。结果 DWI序列上胰腺癌组织相对于癌周组织信号强度比(SIR)高于T1WI及T2WI;正常对照组胰腺组织在DWI图像上均呈均匀中等信号,测的ADC值为(1.933±0.179)×10-3mm2/s;胰腺癌组织在DWI上均呈高信号,ADC值为(1.446±0.201)×10-3mm2/s,低于癌周组织ADC值(1.803±0.291)×10-3mm2/s及急性胰腺炎胰腺组织ADC值(1.783±0.225)×10-3mm2/s。正常对照组胰腺组织、急性胰腺炎组织及癌周组织的ADC值均较胰腺癌组织高,且三者与胰腺癌ADC值比较具有统计学意义(P<0.05)。结论 DWI可以较清楚的显示病灶,并在一定程度上对胰腺癌的诊断及鉴别诊断提供有利的信息。