肝门小胆管癌的多层CT分析

目的:探讨肝门小胆管癌的多层CT影像表现和诊断价值。方法:收集13例经手术及病理证实的直径小于2cm的肝门胆管癌,回顾性分析其多层CT表现。结果:13例病灶CT:平扫均为等密度。增强扫描动脉期10例病灶呈中等强化,3例未见强化;门脉期13例病灶均表现为中等强化,其中见8例肿瘤邻近层面的胆管壁呈不规则的环形强化,其厚度均超过2mm。结论:多层CT对诊断肝门小胆管癌有很大价值。     

肝门部胆管癌的CT和MRI诊断

目的：评价和比较CT和MRI在肝门部胆管癌的分型和诊断中的作用。方法：回顾性分析30例肝门部胆管癌的MRI平扫、增强及MRCP表现，其中13例同时作CT检查，比较两者对肝门部胆管癌的显示能力，并与手术、病理对照。结果：肝门部胆管癌CT与MRI均表现为肝内胆管不同程度的扩张，肝门部见软组织肿块，MRI T1WI呈稍低信号，T2WI呈稍高信号，MRCP表现为肝门部胆管梗阻。对肿块型肝门部胆管癌MRI和CT显示均较好，对浸润型肝门部胆管癌MRI较CT显示好。结论：MRI和CT是检查肝门部胆管癌的有效手段。MRI及MRCP在显示浸润型肝门部胆管癌较CT优越。     

肝门胆管癌的CT诊断

目的:评价螺旋CT对肝门胆管癌的诊断价值。方法:回顾性分析14例经病理证实的肝门部胆管癌的CT表现,评价其对病灶的显示情况及定性诊断的准确率。结果:平扫表现为肝门区低密度软组织肿块;增强扫描14例均有延迟强化;增强检查能更清楚显示肝内胆管扩张和胆管壁增厚。结论:螺旋CT扫描对肝门胆管癌的诊断具有重要意义。     

肝门部胆管癌CT与MRI的诊断价值

目的 探讨CT与MRI对肝门部胆管癌的诊断价值。资料与方法 回顾性分析18例经手术病理证实的肝门部胆管癌的CT与MRI表现,评价两种检查方法对病灶的显示情况及定位诊断的准确率。结果 CT与MRI对肝门部胆管癌的定位诊断准确率分别为88．89％、100％;18例肝门部胆管癌CT与MRI均表现为肝内胆管不同程度扩张;MBI示肝门部软组织肿块16例,胆管壁浸润2例,门静脉受侵10例,淋巴结肿大8例;而相应的CT显示为11、0、5和6例。结论 CT与MRI是检查肝门部胆管癌的有效方法,MRI在显示肝门部肿块大小、范围,沿胆管壁浸润,门静脉侵犯及淋巴结肿大方面比CT更有价值。     

CT导引125I粒子植入治疗肝门部胆管癌支架置入后的应用

目的 探讨CT导引经皮穿刺植入125I粒子治疗肝门部胆管癌支架置入术后的可行性、有效性及并发症.方法 17例肝门部胆管癌患者在胆管内支架置入缓解黄疸后,在CT引导下将125I粒子植入胆管癌病灶内.125I粒子活度2.59×107 Bq(0.7mCi),PD110Gy.术前通过放射性粒子治疗计划系统TPS(treatment planning system)布源,在CT导引下采取粒子间隔0.5～1.0cm,后退式平面植入.术后分别于3个月、6个月和12个月观察病人的客观疗效、胆管内支架通畅情况及手术并发症.结果 所有患者未出现严重并发症.17例患者术后3月,CR1例(5.9％),PR11例(64.7％),NC3例(17.6％),PD2例(11.8％).粒子植入术后3个月时未出现再梗阻;12个月存活的患者(10例)1例出现再梗阻.6个月和12个月生存率分别为82.3％和58.9％,中位生存时间为12个月.结论 CT导引经皮穿刺植入125I粒子治疗支架植入术后的肝门部胆管癌疗效确切,明显减少胆管内支架再梗阻的几率,且无明显副作用,值得进一步探讨.     

多层螺旋CT门静脉和肝静脉成像研究现状

多层螺旋CT门静脉成像可同时显示肝静脉和门静脉系统。近年来,随着该技术的推广,其临床应用日渐广泛,逐步显示出其独特的优势。就多层螺旋CT门静脉、肝静脉成像的检查技术和图像后处理技术的优化进行综述。     

经皮经肝钢圈选择性门静脉栓塞术在肝门部胆管癌术前的应用

目的 探讨肝门部胆管癌扩大肝切除术前使用经皮经肝钢圈选择性门静脉栓塞术(PVE)的应用和疗效.方法 2007年4月至2009年1月收治肝门部胆管癌28例,分为两组,将预保留肝占全肝体积<50%、接受PVE者设为PVE组12例,其中10例最终接受联合扩大肝切除者设为PVE肝切除组;同期未行PVE而接受扩大肝切除术者为非P...     

肝外胆管癌的多期螺旋CT评价

目的探讨肝外胆管癌的CT表现并评价其诊断价值。方法收集2004年10月至2009年8月经手术病理证实肝外胆管癌42例,所有患者均行16层螺旋CT（MSCT）平扫及动脉期、门静脉期、延迟期三期增强扫描。对MSCT各期中肝外胆管癌的显示率、影像表现进行回顾性分析。结果 42例中动脉期、门脉期和延迟期中度以上强化分别为26例、41例和42例。32例根治性手术患者中,MSCT显示肝外胆管癌平均长径18.1±6.3 mm,术后大体标本为20.3±9.5 mm。结论多期MSCT扫描可以较为准确显示肝外胆管癌的位置及范围,在肿瘤术前诊断中具有重要的价值。     

肝门部胆管癌的多层螺旋CT诊断

目的：评价MSCT对肝门部胆管癌的诊断价值。方法：回顾性分析17例行MSCT平扫及动态增强扫描的肝门部胆管癌影像学资料,并与手术及病理对照分析。结果：全部病例均有肝内外胆管扩张,肝内胆管扩张呈软藤状。胆管内肿块（5例）,胆管壁局限增厚和管腔狭窄（12例）,平扫均为等密度。增强扫描3例强化,14例延迟强化。结论：胆管壁局限增厚、胆管内肿块是肝门部胆管癌的较特征性CT征象,MSCT扫描结合薄层三维重建对诊断具有重要意义。     

肝门部胆管癌的低场MRI诊断价值

目的:总结肝门部胆管癌的低场MRI影像表现,以提高对肝门部胆管癌的认识。方法:收集经手术病理证实的肝门部胆管癌21例,均有完整的MRI影像资料。结果:MRCP对肝门部胆管梗阻水平定位准确率达100%。21例肝门部胆管癌均表现为肝内胆管不同程度"软藤样扩张",肝门部胆管狭窄、管壁增厚或软组织肿块;6例MRI肝门部可见稍长T1、稍长T2的肿块影,15例未发现明确肿块;增强扫描5例可见肿块延迟期缓慢持续强化,14例表现为管壁增厚强化、管腔狭窄。结论:低场MRI是检查肝门部胆管癌的有效方法,联合应用MRCP可显示肝门部胆管癌的特征性改变。     

Complications of pyogenic hepatic abscess: computed tomography and clinical features

The purpose of this pictorial essay is to describe the computed tomography (CT) and clinical findings of the various complications of pyogenic hepatic abscesses. The CT and clinical findings of 81 patients who had a confirmed pyogenic hepatic abscess were analyzed retrospectively. Of the 81 patients, 21 cases of various complications from the pyogenic hepatic abscesses were encountered in 17 patients (21%). Two types of complications were observed in 4 patients. These complications included rupture into the pericardial cavity (n = 1), pleuropulmonary complications (n = 11), rupture into the gastrointestinal tract (n = 1), rupture into the peritoneal cavity (n = 3), rupture into the retroperitoneum (n = 1), vascular complications (n = 3), and biliary complications (n = 1). A knowledge of these complications is important for an early diagnosis and appropriate management.     

Gauging effective spatial resolution in multirow helical cardiac computed tomography with a dynamic phantom

PURPOSE: To devise a numerical indicator of image quality for multirow helical cardiac computed tomography (CT) and its relation to temporal resolution. MATERIALS AND METHODS: A pulsatile cardiac assist device was used to simulate cardiac wall motion by mechanically transmitting the device dynamics to a piece of tungsten wire. Wire motion induced by different device rates was captured with an 8-row subsecond helical CT scanner operating with various scanning parameters. Image artifacts were visually assessed and compared with the image point spread function (PSF) using the full width at half maximum (FWHM) area as a numerical estimate of spatial accuracy. RESULTS: At rest, the FWHM area was determined as 1.3 mm2. At a device rate of 60 bpm, the FWHM area ranged from 1.51 mm2 to 21.62 mm2, depending on the time of image reconstruction. Mean reproducibility of the FWHM area measurements was determined as 0.05, whereas visual estimates of motion artifact were highly variable between different readers (kappa = 0.19). Visually determined image quality correlated closely with the FWHM area metric (Spearman's rank correlation, P = 0.0001, rho = 0.841). At a device rate of 100 bpm, the minimum FWHM area was 2.00 mm2 using a single-sector algorithm, 1.41 mm2 using a 2-segment algorithm, and 1.37 mm2 using a 4-segment algorithm. CONCLUSIONS: Use of a pulsatile cardiac assist device could serve as an in vitro test bed for cardiac CT imaging methods. Area FWHM of the PSF correlates well with visually determined image quality of a dynamic phantom, but provides better reproducibility than visual analysis.     

Unusual computed tomography findings in hepatic amyloidosis

An unusual pattern of delayed enhancement in a patient with a focal hepatic defect due to amyloidosis is presented. Without the aid of region-of-interest density measurements, the lesion was not appreciated on unenhanced computed tomography scans.     

Radiological assessment of hepatic vein invasion by hepatocellular carcinoma using combined computed tomography hepatic arteriography and computed tomography arterial portography

Purpose

The aim of this study was to elucidate computed tomography hepatic arteriography (CTHA) and CT arterial portography (CTAP) findings characteristic of hepatocellular carcinoma (HCC) with large hepatic venous invasion (HVI) and then to examine whether the presence of minute HVI can be diagnosed based on each finding.

Materials and methods

Combined CTHA and CTAP of 106 HCCs were examined. Two radiologists analyzed the radiological findings of five nodules with large HVI (group vv2). The remaining 101 nodules were classified into two groups: group vv1, positive minute HVI; group vv0, negative HVI. They examined whether each finding observed in group vv2 could be detected in groups vv1 and vv0.

Results

Analysis of group vv2 identified (a) tumor thrombus, (b) early inflow of the contrast into the hepatic vein proximal to the invaded site, and (c) partially decreased portal venous flow in the peripheral parenchyma subject to the involved hepatic vein. Findings (b) and (c) were observed in 16% of group vv1. A significant difference in frequency of finding (c) was obtained between groups vv1 and vv0. The positive and negative predictive values of finding (c) were 66.7% and 77.9%, respectively.

Conclusion

Findings (b) and (c), especially the latter, may partly contribute to the radiological diagnosis of minute HVI.     

C-arm computed tomography for guiding hepatic vascular interventions

C-arm computed tomography (C-arm CT) represents the next generation of imaging technology available in the angiography suite that is predicted to be the platform for many of the three-dimensional (3D) road mapping and navigational tools that will emerge in conjunction with its implementation. The combination of current and unappreciated capabilities may be the foundation on which improvements in both safety and effectiveness of complex hepatic vascular interventional procedures become possible. These improvements include multiplanar soft tissue imaging, pretreatment target lesion vascular road mapping, and the ability for immediate posttreatment assessment. These key features alone may translate into a reduction in the utilization of iodinated contrast used by the operator, as well as a decrease in the radiation dose to the patient and the operator, in addition to increasing the therapeutic index (increase in the safety versus benefit ratio). In routine practice, imaging information obtained with C-arm CT provides a subjective level of confidence factor to the operator that has not yet been quantified.     

Transient hepatic attenuation differences on dynamic computed tomography

Transient hepatic attenuation differences (THAD) are occasionally noted on dynamic CT in patients with portal vein obstruction, arterioportal shunt, liver tumor, and liver abscess. We report four additional cases of THAD with unreported and/or unexplained etiology.     

Enhancement pattern of hilar cholangiocarcinoma: Contrast-enhanced ultrasound versus contrast-enhanced computed tomography

Objective

To compare the enhancement pattern of hilar cholangiocarcinoma on contrast-enhanced ultrasound (CEUS) with that on contrast-enhanced computed tomography (CECT).

Methods

Thirty-two consecutive patients with pathologically proven hilar cholangiocarcinomas were evaluated by both low mechanical index CEUS and CECT. The enhancement feature of the tumor, portal vein infiltration, and lesion conspicuity on them was investigated.

Results

In the arterial phase, the numbers of the lesions showing hyperenhancement, isoenhancement, and hypoenhancement, were 14 (43.8%), 14 (43.8%), and 4 (12.6%), on CEUS, and 12 (37.5%), 9 (28.1%), and 11 (34.4%), on CECT (P = 0.162). In portal phase, the numbers of the lesions showing hypoenhancement, isoenhancement, and hyperenhancement were 30 (93.8%), 1 (3.1%), and 1 (3.1%), on CEUS, and 23 (71.9%), 8 (25.0%), and 1 (3.1%), on CECT (P = 0.046). The detection rates for portal vein infiltration were 84.2% (16/19) for baseline ultrasound, 89.5% (17/19) for CEUS, and 78.9% (15/19) for CECT (all P > 0.05 between every two groups). CEUS significantly improved the lesion conspicuity in comparison with CECT. CEUS and CECT made correct diagnoses in 30 (93.8%) and 25 (78.1%) lesions prior to pathological examination (P = 0.125).

Conclusion

The enhancement pattern of hilar cholangiocarcinoma on CEUS was similar with that on CECT in arterial phase, whereas in portal phase hilar cholangiocarcinoma shows hypoenhancement more likely on CEUS. CEUS and CECT lead to similar results in evaluating portal vein infiltration and diagnosis of this entity.     

Prolonged hepatic enhancement on computed tomography in a case of hepatic lymphoma

Hepatic lymphoma is often very difficult to detect using any modality. A case of hepatic lymphoma appeared on rapid contrast infused CT as extremely prolonged and bizarre enhancement. The specific features included a widespread and aggressive appearance with a variable pattern of contrast enhancement. There was one localized area of apparent centripetal accumulation of contrast medium. The prolonged and irregular enhancement may be due to contrast medium "trapping" in interstitial spaces or even to the fact that a bolus technique was used.     

Evaluation of the pulmonary hilum: comparison of conventional radiography, 55 degrees posterior oblique tomography, and dynamic computed tomography

In 84 patients with suspected intrathoracic neoplasms we compared the accuracy of conventional radiography, 55 degrees posterior oblique tomography, and contrast-enhanced dynamic incremental computed tomography (CT) in evaluation of the pulmonary hilum. We found dynamic incremental CT to be better than either conventional radiography or oblique tomography in hilar evaluation. In addition, significant information was detected in extrahilar and extramediastinal locations by CT in 21% of patients. This study, unlike earlier reports, indicates a role for CT in hilar evaluation.