Detection and characterization of focal liver lesions with contrast-enhanced ultrasonography in patients with hepatitis C-induced liver cirrhosis

Background: Hepatitis C virus (HCV)-associated liver cirrhosis provides a major preneoplastic condition for hepatocellular carcinoma (HCC). Ultrasonography (US) is usually used for screening of HCC, but needs improvement.

Purpose: To assess whether use of a second-generation ultrasound contrast agent can improve characterization of focal liver lesions and detection of HCC in HCV-infected patients with liver cirrhosis.

Material and Methods: In total, 96 US studies in 49 HCV-infected patients with liver cirrhosis were performed. The patients were first examined with a baseline US. After this, a diagnostic decision was made and recorded. The patients were then re-examined with contrast-enhanced ultrasound (CEUS), and the diagnostic triage was repeated. The patients were followed up for at least 1 year.

Results: On baseline US, indeterminate focal lesions were found in 27 examinations. After CEUS, a confident diagnosis of HCC was made in eight of these examinations. In an additional eight US examinations, diagnosis of regenerative/dysplastic noduli was established. In one patient with no detectable focal lesion at baseline examination, an indeterminate malignant lesion was detected with CEUS. This lesion was further investigated with computed tomography and diagnosed as HCC.

Conclusion: Our study indicates that the use of CEUS significantly improves diagnostic confidence. CEUS improves the detection of HCC in patients with HCV-induced liver cirrhosis. Also, CEUS makes it possible to rule out malignancy in many cases where baseline US shows indeterminate focal lesions. In low-endemic countries, the use of CEUS in screening for HCC may be considered.     

High-resolution T2-weighted abdominal magnetic resonance imaging using respiratory triggering: impact of butylscopolamine on image quality

Background: Respiratory triggering allows the acquisition of high-resolution magnetic resonance (MR) images of the upper abdomen. However, the depiction of organs close to the gastrointestinal tract can be considerably impaired by ghosting artifacts and blurring caused by bowel peristalsis.

Purpose: To evaluate the effect of gastrointestinal motion suppression by intramuscular butylscopolamine administration on the image quality of a respiratory-triggered T2-weighted turbo spin-echo (T2w TSE) sequence of the upper abdomen.

Material and Methods: Images of 46 patients were retrospectively analyzed. Twenty-four patients had received intramuscular injection of 40 mg butylscopolamine immediately before MR imaging. Fourteen of the 24 patients in the butylscopolamine group underwent repeat imaging after a mean of 29 min. Quantitative analysis of the ghosting artifacts was done by measuring signal intensities in regions of interest placed in air anterior to the patient. In addition, image quality was assessed qualitatively by two radiologists by consensus.

Results: Spasmolytic medication with butylscopolamine reduced ghosting artifacts and significantly improved image quality of the respiratory-triggered T2w TSE sequence. The most pronounced effect of butylscopolamine administration on image quality was found for the pancreas and the left hepatic lobe. The rate of examinations with excellent or good depiction of the pancreas and the left hepatic lobe in the group without premedication and in the butylscopolamine group was 55% vs. 96% (pancreatic head), 35% vs. 88% (pancreatic body), 43% vs. 96% (pancreatic tail), and 45% vs. 83% (left hepatic lobe), respectively. Regarding the duration of the effect of intramuscular butylscopolamine, repeat imaging after a mean of 29 min did not result in a significant deterioration of image quality.

Conclusion: Intramuscular butylscopolamine administration significantly improves image quality of respiratory-triggered T2-weighted abdominal MR imaging by persistent reduction of peristaltic artifacts. MR imaging of the liver and pancreas in particular benefits from the suppression of gastrointestinal peristalsis by butylscopolamine.     

视神经炎的MRI表现及与视觉诱发电位的相关性研究

目的 探讨诊断视神经炎的有效MR检查序列、MRI表现及其与视觉诱发电位(VEP)的相关性.方法 对98例(154只眼)诊断为视神经炎、视神经乳头炎、多发性硬化、视神经脊髓炎的视力下降患者MRI资料进行分析,并与VEP结果及临床视力表现做x2检验、秩和检验和一致性分析.结果154只患眼中56条视神经增粗,76条形态不变,22条变细.MR短时间反转恢复(STIR)序列显示132条视神经呈异常高信号.异常信号累及范围包括视神经球壁段7条,眶内段135条,管内段109条,颅内段97条,视交叉受累56例,视束受累23条.54例行钆喷替酸葡甲胺(Gd-DTPA)增强枪查者,87只患眼中74条视神经强化.98例患者共196只眼中,视力下降同时视神经MRI信号异常者132只眼,视力正常、视神经MRI信号正常者26眼,MRI与视力表现之间的一致率为80.61%(Kappa=0.453,P＜0.01).住获得VEP结果的175只眼中,视力下降同时VEP异常者129只眼,视力正常、VEP正常者30只眼,VEP与视力表现之间的一致率为90.86%(Kappa=0.731,P＜0.01);视神经MRI信号异常及VEP异常者117只眼,MRI信号正常、VEP正常者24只眼,MRI表现与VEP之间的一致率为80.57%(Kappa=0.460,P＜0.01).结论MR STIR序列和Gd-DTPA增强扫描联合脂肪抑制技术有助于视神经炎定位和定性诊断,VEP有助于视神经炎的诊断和亚临床病灶发现,MRI结合VEP能提高视神经炎诊断的准确率.     

动态增强MRI定量参数及最大线性斜率比值对鉴别乳腺良恶性疾病的价值

目的 通过对动态增强MRI时间.信号强度曲线(TIC)的后处理,寻找有效的鉴别诊断良、恶乳腺疾病的定量参数.方法 回顾性分析行MR检查的30例乳腺疾病初诊患者,对动态增强MRI的TIC进行后处理,得出最高信号强度(SImax)、强化峰值(PH)、最大线性斜率(Slope)、最大线性斜率比值(SlopeR)4个定量参数,用独立样本t检验和秩和检验评价4个定量参数在良、恶性病灶间的分布是否具有统计学意义.结果 共17个良性病灶和18个恶性病灶,良性病灶和恶性病灶的SImax值(M值)分别为375.2和158.1,95%可信区间分别为278.2～506.0和160.5～374.8;PH值(M值)分别为114.4和87.8.95%可信区间分别为73.7-196.5和71.3~162.9;Slope值(M值)分别为22.3×10-3和44.0×10-3,95%可信区间分别为13.7×10-3~41.1×10-3和46.1×10-3~81.8×10-3;SlopeR值(M值)分别为2.6和11.4,95%可信区间分别为1.9～3.4和9.8~14.5.SImax、PH值在良、恶性病灶间的分布差异无统计学意义(P值均>0.05);Slope值在良、恶性病灶间的分布差异具有统计学意义(P<0.01),但曲线下面积重叠较大;SlopeR值在良、恶性病灶间的分布差异具有统计学意义(P<0.01),曲线下面积重叠少.结论 SlopeR值对乳腺良、恶性病灶间的鉴别有重要意义.     

64层螺旋CT对心尖肥厚型心肌病的临床应用研究

目的 探讨64层螺旋CT(MSCT)在心尖肥厚型心肌病(AHCM)中的临床价值.方法 搜集AHCM患者21例,其中14例经超声心动图(UCG)确诊,UCG检查阴性的7例经MRI确诊.所有患者均行MSCT检查,5例患者有左心室和冠状动脉导管造影对照.(1)利用MSCT后处理工作站分别测量左心室各节段舒张末期和收缩末期室壁厚度并计算心尖部室壁增厚率(LVAT),计算左心室心尖部舒张末期最大室壁厚度(LvA)和左心室基底段后壁舒张末期室壁厚度(LVPW)的比值(LVA/LVPW);利用心功能分析软件定量测量左心室舒张末期容积(LVEDV)、射血分数,与对照组30名正常人MSCT测量结果进行对比分析,采用独立样本的t检验进行统计学分析.(2)利用MSCT血管分析软件判断冠状动脉血管有无狭窄并测量狭窄率.结果 MSCT左心室四腔面和两腔面观察AHCM患者在左心室舒张末期均显示心尖部心肌呈弥漫性或节段性增厚,导致左心室心腔变形.定量分析显示AHCM组和对照组LVEDV分别为(82.6±11.4)与(108.5±10.6)ml;心尖部LVA分别为(20.6±3.4)与(9.9±1.5)mm;LVA/LVPW比值分别为2.1±0.5与1.1±0.2;LVAT分别为(25.6±4.7)%与(81.5±8.5)%,以上指标差异均有统计学意义(t值分别为8.32、15.29、9.91和27.30,P值均＜0.05);LVPW和左心室射血分数(LVEF)2组比较差异无统计学意义(t值分别为0.26和1.13,P值均＞0.05).MSCT血管分析软件显示21例患者中5例肌壁内冠状动脉-心肌桥形成,4例出现血管狭窄,其中1例1支血管狭窄＞70%诊断冠心病.5例患者行左心室和冠状动脉导管造影检查,所见与MSCT相符.结论 MSCT能准确诊断AHCM,实现了心脏解剖、功能和冠状动脉的综合评价,避免了有创冠状动脉造影和重复检查对患者带来的不便,在评价心肌血流灌注、心肌活性方面表现出良好的应用前景.     

氡及其子体辐射诱发的非癌变效应

氡暴露与循环系统疾病的关系以及氡对风湿性疾病的治疗作用已日益受到关注.从铀矿工的流行病学系统回顾中,揭示出氡暴露与冠心病之间存在相关关系.此外,随机对照实验证实,氡浴可以明显改善风湿病的疼痛、晨僵等症状.     

爆炸冲击波对羊肝形态的影响

目的：观察三硝基甲苯（TNT）炸弹爆炸对肝组织的病理损伤特征，为爆炸伤的临床救治提供依据。方法：将25只健康山羊围绕爆心呈扇形布放于5～30m不同距离处，用电启动引爆TNT致伤动物。严密观察动物伤情，存活至4h的以颈动脉放血方式处死后，解剖观察肝脏组织，用40mg／L多聚甲醛固定制备石蜡标本、HE染色、光镜观察其组织病理改变。结果：距爆心5m处动物全部死亡（2／2），10m处死亡3只（3／5），15m处死亡2只（2／5），20m处死亡1只（1／5），25m和30m处各4只动物无一死亡（0／4）。肝组织的损伤主要是肝细胞空泡样变性、血窦淤血、出血明显；汇管区均有不同程度淤血、出血、炎性细胞浸润及胆管上皮细胞坏死脱落；非即刻死亡动物可出现中性粒细胞浸润。结论：致伤情况与动物分布距离密切相关，距爆心越近，死亡率越高。炸弹爆炸产生的冲击波可造成肝组织明显损伤。     

MR-guided liver biopsy within a short, wide-bore 1.5 Tesla MR system

The purpose of this study was to evaluate the diagnostic efficacy of magnetic resonance (MR)-guided biopsy of focal liver lesions within a short, wide-bore 1.5-T MR system and to determine the duration and accuracy of needle placement using MR fluoroscopy guidance in 25 patients. Accuracy of needle placement was evaluated in two orthogonal planes, and the out-of-plane angle of needle deflection was measured. Needle positioning was characterised subjectively as centred, peripheral, or exterior relative to the lesion. Exterior positioning was corrected by a step-by-step procedure. Surgical resection (n = 6), previous histologies (n = 8), or clinical/radiological follow-up (n = 11) served as the ‘gold standard’. The guidance needle could be placed successfully using MR fluoroscopy in 20 of 25 patients (80%). Needle placement was rated as ‘centred’ in 11 and as ‘peripheral’ in nine patients. Median needle deflection was 2.6 degrees, with a median deviation of 3.4 mm. In five patients, the direct approach failed or was rated as ‘exterior’; therefore, repositioning after needle stabilisation with a stainless-steel stylet was necessary. The diagnostic yield of all biopsies was: sensitivity 95.5%, specificity 100.0% and accuracy 96.0%. In conclusion, MR-guided biopsies in a short, wide-bore MR system yielded highly reliable biopsy results, and in most cases the direct approach with MR fluoroscopy guidance proved to be fast and accurate.     

秀丽隐杆线虫在神经科学研究中的应用

模式生物秀丽隐杆线虫(C. elegans)是多细胞无脊椎动物,其中神经细胞占体细胞的三分之一之多.虽然解剖结构十分简单.但神经递质、突触蛋白、离子通道等基本组成与人类具有高度的保守性.由于其全基因组遗传信息已知,基因操作便捷,秀丽隐杆线虫已经在高级神经功能活动、神经系统疾病等研究领域中发挥重要作用.本文就秀丽隐杆线虫在神经科学研究中的应用进行综述.     

多层螺旋CT血管成像在下肢静脉阻塞性病变中的临床应用

目的 探讨多层螺旋CT血管成像(MSCTA)在下肢静脉阻塞性病变中的临床应用价值.方法 对52例临床疑有下肢静脉阻塞性病变的患者行16层螺旋CT扫描及血管三维重建, 分析CT血管成像技术,其中44例患者做了DSA检查,与DSA检查进行比较,评价MSCTA在下肢静脉阻塞性病变中的应用价值.结果 44例患者中有26例髂静脉受压综合征,其中12例合并下肢深静脉血栓形成.下肢深血栓形成病例共27例.5例CT检查显示其他原因的阻塞:布-加氏综合征1例合并两下肢深静脉广泛血栓形成、左侧腹股沟区囊肿压迫左侧髂外静脉1例、盆腔肿块压迫左侧髂总静脉2例、右侧输尿管肿瘤复发侵犯右髂外静脉1例.下肢深静脉血栓形成合并肺动脉栓塞5例.以DSA为诊断标准,下肢静脉阻塞性病变的MSCTA诊断符合率为100%.结论 MSCTA对下肢静脉阻塞性病变的诊断有较高的临床应用价值.