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排序方式: 共有502条查询结果,搜索用时 15 毫秒
1.
胆管癌误诊和漏诊的影像学分析   总被引:1,自引:0,他引:1  
目的:分析胆管癌误诊和漏诊的原因,评价不同检查方法对肝门区胆管癌诊断的价值,提高胆管癌的影像学诊断和鉴别诊断水平。方法:收集31例临床和病理诊断为胆管癌的病例(ERCP检查31例,B超检查31例,25例CT检查,11例行MRCP检查),回顾性分析不同检查方法的影像学表现。结果:31例中发生在肝门区的胆管癌25例。2例初次ERCP显示胆管内出血,再次行鼻胆管造影后诊断为胆管癌,4例合并有总胆管结石。6例为总胆管中下段癌。初次诊断准确性为90.3%。11例MRCP中9例显示病变,2例显示不满意,7例显示胆管或胆囊结石。25例CT中23例显示肝内胆管扩张,9例显示肝门区肿块,2例见后腹膜转移淋巴结,1例见肝内多发性转移瘤。12例初次诊断正确(48%)。B超检查23例提示肝内胆管扩张,6例提示总胆管结石,18例诊断为胆囊炎、胆囊结石,8例提示胆管占位(25.8%)。结论:良好的直接胆管造影是诊断胆管癌的金标准,MRCP可以在一定程度上准确显示病变的范围,是ERCP的良好补充,很大程度上取代了诊断性ERCP;CT诊断的关键在于显示扩张的胆管和梗阻的定位,肝门区梗阻多为胆管癌所致。多种影像检查方法的结合明显提高了诊断的准确性,对胆管癌治疗方案的选择有重要价值。  相似文献   
2.
Symptomatic BDS commonly cause significant morbidity and attempt at stone removal should be attempted if possible. Complications of CBDS include biliary colic, jaundice, cholangitis and pancreatitis. Investigations aimed to predict the presence of stones within the bile duct include serum bilirubin, AST, ALP, common bile duct diameter and age as independent predictors of choledocholithiasis. TUS is a sensitive test in detecting bile duct dilatation but the sensitivity is reduced in its ability to detect choledocholithiasis. A NIH consensus statement found that ERC, MRC and EUS were comparable in their sensitivities, specificities and accuracy rates for detection of choledocholithiasis. ERC and stone removal using a balloon or basket is often performed following EST. EBD may be performed if patients have uncorrected coagulopathies but the risk of pancreatitis is higher than for EST (although the risk of bleeding complications is lower for EBD). ML is often required in difficult to remove CBDS and using this device, CBDS can be removed in 90–95% of cases. Other forms of lithotripsy including laser lithotripsy and EHL are confined to specialised centres and the evidence for their use is based on small studies. ESWL may clear stones from the bile duct in up to 93% of patients but frequently ERC and stone fragment removal is required post ESWL. The role of medical therapy in difficult to remove CBDS (or in CBDS in patients with severe co-morbid illness preventing ERC + stone removal) is still currently uncertain due to a lack of large randomised control trials.  相似文献   
3.
肝外胆管梗阻病变MSCT曲面重建胆管成像与MRCP的比较研究   总被引:1,自引:0,他引:1  
目的比较多层螺旋CT(MSCT)曲面重建(CPR)胆管成像与磁共振胰胆管成像(MRCP)对肝外胆管梗阻病变的诊断价值。方法66例经B超检查提示有肝外胆管梗阻病变的患者,采用单次激发快速自旋回波(SSFSE)序列,行MRCP检查,同期采用10mm层厚层距,使用血管对比剂,行MSCT增强扫描,将门静脉期图像采用2.5mm层厚、1.25mm层距重建,获得轴面源像(ASI),数据传输至图像工作站,作CPR胆管成像。比较CPR胆管成像、MRCP对肝外胆管梗阻病变的定位、定性诊断价值。结果CPR胆管成像、MRCP成功率为100%;CPR胆管成像、MRCP均对肝外胆管梗阻部位做出明确诊断,定位诊断率为100%;CPR胆管成像、MRCP定性诊断率分别为95.5%和80.9%。结论CPR胆管成像、MRCP对肝外胆管梗阻病变均能明确定位,CPR胆管成像定性诊断率明显高于MRCP,CPR胆管成像显示胆管及其周围病变与扩张胆管的关系更直观。  相似文献   
4.
MRI的普及,创造了临床诊断及治疗指导的进步,普外科领域的胆胰系造影应用的广泛性越来越高,MRCP对有病变的肝内胆管,胆囊、胰管显影良好,可以应用于胆飞胰系疾病的诊断及指导治疗,成功率高,与ERCP相比,均可得到同样的胆道、胰管的显像,无并发症,无创伤性,检查方便,应用前景看好.  相似文献   
5.
目的:分析总结MRCP诊断胆总管结石的重要性。方法:通过30例经过手术确诊的胆总管结石病例,进行分析比较。结果:29例MRCP术前诊断胆总管结石,术后予以确诊,1例可疑结石,诊断准确率96.6%,B超术诊断结石16例,检出率53.3%,明显低于MRCP。结论:MRCP辅以常规MR扫描诊断胆总管结石准确率高,是安全、有效的检查方法,得到临床的广泛应用。  相似文献   
6.
A 70-year-old woman with gastric cancer was referred to our hospital for further evaluation of a cystic mass in the head of the pancreas. Endoscopic ultrasonography (EUS) showed a mural nodule in the cystic mass. Endoscopic retrograde cholangio pancreatography (ERCP) revealed a cystic lesion with a filling defect caused by obstruction with mucus. Magnetic resonance cholangiopancreatography (MRCP) allowed visualization of the entire configuration of the cystic lesion despite the presence of mucus. Pancreatic juice was positive for K-ras point mutation. Pancreatoduodenectomy was performed, with a diagnosis of intraductal papillary adenoma or adenocarcinoma with gastric cancer. Pancreatography of the resected specimen showed a cystic lesion in the uncinate process, consistent with the MRCP findings. Histological examination revealed an intraductal papillary adenoma. MRCP is very useful for demonstrating the total configuration of cystic lesions and is not impeded by impacted mucin. Nevertheless, because of its lower spatial resolution, this noninvasive modality is of limited value in detecting mural nodules. At present, therefore, surgical indications for cystic lesion of the pancreas should be determined by comprehensively analyzing: size and sequential changes in size of the cyst; presence of mural nodules, cytologic examination for presence of malignant cells, and/or K-ras point mutation in pure pancreatic juice.  相似文献   
7.
目的:分析与探讨MRI平扫及MRCP显示十二指肠乳头腺癌合并胆道梗阻的应用价值。方法选取100例2013年2月—2014年8月在该院接受诊断的十二指肠乳头腺癌合并胆道梗阻患者,以随机方式将其平均分为两组,即:对照组与观察组,对对照组患者实施常规诊断,对观察组患者实施MRI平扫及MRCP检查。两组患者诊断结果和病例相对照。结果对照患者病例,观察组患者病变诊断准确率为90.0%,对照组患者病变诊断准确率为50.0%,观察组明显优于对照组,差异有统计学意义(P<0.05)。结论研究表明,MRI平扫及MRCP能够有效显示十二指肠乳头腺癌合并胆道梗阻,该诊断方式对选择临床治疗方式具有重要价值,值得临床应用与推广。  相似文献   
8.
9.
《Pancreatology》2014,14(2):117-124
PurposeIntraductal pancreatic mucinous neoplasms (IPMN) are precancerous cystic lesions. The aim was to investigate the in situ IPMN proteome using MALDI (Matrix-Assisted Laser Desorption/Ionisation) imaging and to characterize biomarkers associated with the grade of dysplasia.Experimental designFrozen human Branch duct -IPMN sections were selected according to dysplasia and proteomic analyses were performed by MALDI imaging to obtain mass spectra distribution. The most discriminating peaks were identified using tissue extraction and nanoLC-ESI-MS/MS. Identified peaks were validated in independent series of IPMN by immunochemistry on surgical specimens (tissue-microarrays (TMA), n = 45) and endoscopic ultrasound fine-needle aspiration (EUS FNA) samples (n = 25).ResultsBD-IPMN samples with low (n = 10) and high (n = 10) grades of dysplasia were analyzed. Differential spectra of proteins were found in the two groups with significantly different intensities (n = 15). The two peaks (intense in high grade IPMN) (m/z 8565 and 4747) were characterized as the monomeric ubiquitin (Mascot score = 319.22) and an acetylated fragment of thymosin-β4 (2–42) (Omssa score = 1.37 E−9). Validation on TMA and EUS FNA samples confirmed that ubiquitin was overexpressed in high grade dysplasia (p = 0.04 and p = 0.0004). Thymosin-β4 expression was confirmed on TMA by immunohistochemistry on high grade IPMN (p = 0.011).ConclusionUbiquitin and thymosin-β4 are overexpressed in IPMN with high grade dysplasia. Positive immunochemical staining on EUS-FNA material is a major argument in support of preventive resection.  相似文献   
10.
目的 探讨磁共振胰胆管成像(MRCP)在胆石症病人中的临床应用价值。方法 通过对87例术前行MRCP检查的胆石症病人和66例术前未行MRCP检查的胆石症病人的对比研究,比较两组术后胆道残石的发生率和胆道阴性探查率。结果 发现在有胆道相对探查指征的病人中,术前MRCP检查的阴性率为23%,术后残石率为1.5%,胆道阴性探查率为0;而未行MRCP检查的胆石症病人的残石率为9.1%,胆道阴性探查率为18.2%。结论术前MRCP检查可降低胆道阴性探查率,避免不必要的胆道探查,还可降低胆道残石发生率。  相似文献   
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