肝硬化结节自然病程的磁共振功能成像研究进展

肝硬化结节性病变经过肝硬化再生结节(RN)、低级别退变结节(DN)、高级别DN、DN癌变,最终演变成小肝癌.鉴别肝硬化结节病变病程的不同阶段对临床早期检测癌变结节,进行早期干预、提高病人生存率具有重要意义.介绍肝脏RN、DN及其癌变结节病理学特点及常规MRI影像学特点,并着重对磁共振功能成像的原理及其在肝硬化结节的应用现状及前景予以综述.     

DWI在肝硬化癌前病变鉴别诊断中的临床价值

目的 探讨核磁共振弥散加权成像(DWI)技术ADC值在肝硬化再生结(RN)、癌前病变(DN)、早癌及原发性小肝癌(SHCC)的鉴别诊断中价值.方法 采用ADC值测定结合容积采集技术LAVA动态扫描,在228例肝硬化患者中,再生结节性(RN)患者121例,DN结节9例,原发性肝癌98例,其中小肝癌(SHCC)及早期小癌(ESHCC)21例;正常组90例;测定ADC值的演变过程.结果 本研究鉴别诊断RN结节、DN结节、HCC的检出率分别为45.15％、3.36％、36.57％,其中SHCC及ESHCC的检出率7.84％.测定RN结节的ADC值为(2.0±0.22)×10-3 mm2/s、DN结节的ADC值为(1.50±0.27)×10-3 mm2/s,演变为SHCC或ESHCC时其ADC值下降为(1.17±0.19)× 10-3 mm2/s.结论 随着肝硬化-再生结节-癌前结节-肝癌的病理演变过程,其ADC值呈逐渐下降趋势,各组ADC均值存在显著性差异(P＜0.05),DWI技术可以对肝硬化各个阶段病变进行较为准确可信的判断.     

小b值ADC及DWI信号强度与肝硬化结节及小肝癌血供的关系

目的:研究DWI对肝硬化DN、恶变结节及sHCC的ADC值及DWI信号强度与相应血供的关系。材料和方法:共19例经病理证实的肝硬化恶变结节及原发性小肝癌。根据病灶动态增强特点区分DN、恶变结节及sHCC。采用两组小b值(b低=0mm2/s,b高分别为2mm2/s及50mm2/s)对病灶及正常肝脏ADC值、信号强度及CER值进行计算。结果:恶变结节及sHCCADC值、DWI信号强度及CER值均明显高于DN及正常肝组织(P<0.05)。两组b值中测量肝硬化恶变结节及sHCC与DN及正常肝组织DWI信号强度差与CER值差均呈正相关(r=0.832),而ADC值与CER值差间不相关。结论:小b值DWIADC值受病灶血流灌注的影响较大,且血供丰富的恶变结节及sHCCADC值最高,DWI信号强度也最高。结合DWI及动态增强表现可以明显的提高肝硬化恶变结节/sHCC的诊断准确性。     

DWI及ADC值在肝脏弥漫性疾病诊断中的应用价值

目的:探讨肝脏常见弥漫性疾病的ADC值及DWI上信号强度与相应血供相关性。方法:共110例(19例肝硬化癌变结节、20例肝转移性肿瘤、35例海绵状血管瘤和36例肝囊肿)弥漫性肝占位进行磁共振扫描并计算感兴趣区ADC值、信号强度及增强率。结果:癌变结节与DN及正常肝组织间ADC值相比明显高于后两者,P<0.05。肝囊肿、海绵状血管瘤、肝硬化癌变结节及转移性肝癌在DWI上均为明显高信号。结论:DWI及ADC值对于鉴别弥漫分布的肝脏恶性实质肿块与肝硬化再生结节及良性富水肿块(血管瘤及囊肿)有重要的诊断价值,尤其是在弥漫分布的肝硬化再生结节中发现癌变结节,有其重大的临床意义。     

肝内再生性结节、增生性结节和小肝癌的磁共振征象与鉴别

目的 分析肝内再生性结节(RN)、增生性结节(DN)和小肝癌(SHCC)的磁共振成像特点及鉴别诊断.方法 磁共振平扫及动态增强检查并经病理证实的RN中大结节17个病灶, DN 16个病灶及SHCC 45个病灶,观察病灶的大小、信号强度、强化的方式和时间、包膜等,并绘制时间信号强度曲线.结果 (1)RN: 平扫呈T1W高、T2W低的信号,10个病灶压脂后信号增高,时间-信号强度曲线显示为缓慢上升型.(2)DN: 4个病灶表现为"结中结",中央结节为T1W低、T2W等或高信号,动态增强为速升速降或速升缓降型,周围为T1W高、T2W等或低信号,动态增强为缓慢上升型;余12个病灶T2W为等和稍高信号,动态增强为速升缓降型.(3)SHCC: T1W低信号(35/45)、T2W高信号(42/45)为主,动态增强为速升速降型占71.1%;62.2%病灶可见包膜,3个病灶压脂后信号减低,3个病灶可见镶嵌征.结论 磁共振平扫结合动态增强可对肝内不同性质的结节(RN,DN和SHCC)鉴别.     

HBV相关肝硬化结节演变的多模态MRI研究

目的:通过与病理结果进行对照分析,总结肝硬化再生结节多步演变的多模态MRI影像特征,探讨肝硬化再生结节的早期诊断及鉴别诊断价值.方法:搜集乙肝肝硬化患者50例(85个结节),回顾性分析其MRI平扫及增强扫描资料,对病理证实的多步演变结果与对应的MRI影像表现进行对照研究.结果:MRI检出82个结节,检出率为96.5％,T2 WI和动态增强扫描是检测再生结节较敏感的序列,检出率分别为93.9％和96.3％,磁敏感成像(SWI)的检出率稍低(69.5％);再生结节(RN)与低级不典型增生结节(LGDN)(x2=8.348,P=0.004)、高级不典型增生结节(HGDN)与肝细胞癌(HCC)(x2=4.612,P=0.032)的MRI诊断符合率差异均有统计学意义.T1WI图像上LGDN的信噪比(SNR)值与RN、HGDN、HCC比较差异均有统计学意义(P值均＜0.05);T2 WI图像上HCC的SNR值与RN、LGDN、HGDN比较差异均有统计学意义(P值均＜0.05).结论:MRI是目前检测肝硬化结节最敏感的无创性检查方法,通过MRI与病理的对照分析,多模态序列从不同角度反映了肝硬化再生结节的影像学特征及演变规律,对肝硬化再生结节的诊断及鉴别诊断具有一定价值.     

肝硬化结节与小肝癌的MRI研究

目的:回顾性分析肝硬化合并小肝癌、再生结节(RN)及肝不典型增生结节(DN)的MR表现,探讨其MR诊断与鉴别诊断。方法:收集50例结节性肝硬化病例MR检查资料,患者行正反相位T1WI、脂肪抑制T2WI、动态增强扫描和弥散加权(DWI)扫描,总结肝内结节的信号特点。结果:RN在T1WI脂肪抑制上多为等信号或稍高信号,T2WI多为低信号,增强后与周围正常肝组织强化相似或信号稍低;DN在T1WI多为较高信号,T2WI多为稍低或等信号,增强后强化不明显;癌结节T1WI多为稍低或等信号,偶有稍高信号,T2WI多为较高信号,DWI为高信号,强化多为动脉中晚期强化,门静脉期以后强化减退。结论:磁共振平扫加动态增强能对大多数RN、DN和小肝癌结节做出明确诊断和鉴别。     

MRI及其定期随访对肝硬化结节癌变的诊断价值

目的探讨MR及定期随访在肝硬化结节癌变诊断中的价值,旨在早期发现肝硬化结节癌变。方法回顾性分析经病理或手术证实48例肝硬化结节恶变患者的T1WI、T2WI、增强扫描、DWI表现及随访资料,分析肝硬化结节恶变MR表现、信号变化。结果48例患者共66个病灶,T1WI呈等、低信号,偶有高信号;T2WI多为稍高信号,亦可见等信号;三期增强扫描“快进快出”、“快进慢出”、“持续性强化”都可出现,典型“快进快出”为主;DWI呈高信号多见。部分病灶首次MR检查并未发现癌变,随访过程中T2WI信号增高,强化方式改变或进行性增大等改变,后经证实已癌变。结论磁共振常规技术及DWI能对大多数肝硬化结节癌变做出明确诊断,定期随访能早期发现结节恶变,明显提高诊断准确率。     

肝硬化相关结节的MRI研究与进展

肝硬化结节癌变经历再生结节、低级别不典型增生结节、高级别不典型增生结节到小肝癌,是一个多步骤的过程,其演变过程中重要的特征是血流动力学的改变.早期诊断和鉴别这些不同性质的肝硬化结节非常重要,MRI作为无创性的影像学方法,在肝硬化相关结节的诊断中起着重要作用,就肝硬化相关结节的MRI的研究进展予以综述.     

MRI对肝硬化伴肝癌和非典型性结节诊断的敏感性观察

 目的探讨MRI对肝硬化伴肝癌和非典型性结节的敏感性.方法74例肝硬化患者肝移植前90d内行MRI检查,并同肝移植术后病理切片作对照.所有患者检查前均不知其有无肝癌,FLASH/T1WI、TSE/T2WI序列、动态3期增强扫描被获得.结果病理发现13例患者共21处肝脏有恶性病变,MRI发现其中12/21个恶性病变,敏感性为57.1%,其中发现87.5%(7/8)≥2cm的病变,44.4%(4/9)1～2cm的病变,25.0%(1/4)＜1 cm的病变;对≥2cm和＜2cm组的恶性病变的差异有统计学意义(P＜0.05).病理检查发现14例患者(14/74)共47个DN,MRI诊断9/47个DN病变,敏感性仅19.1%.结论MRI对肝硬化伴＞2cm的肝癌敏感性较好,但对＜2cm的肝癌及非典型性结节敏感性较差.     

Optimization of the system of medical service of students of Cadet Schools of the Ministry of Defense of the Russian Federation

One of the factors of the successful military career guidance Cadet schools students is preserving and promoting their health. Medical support of children and adolescents aged 10-17 years should include the full range of medical and preventive measures defined for this group. The state of providing outpatient care for pupils at the Cadet School in St. Petersburg was studied. These results show that full medical care in accordance with the standards can be based only on children's health clinics. It is important that the organization of medical support pupils cadet schools should be cooperate with civilian health care.     

带状疱疹83例误诊原因分析

带状疱疹是由水痘—带状疱疾病毒引起的皮肤科常见疾病。其主要的病理损害,一是受累神经的严重炎症性浸润,继而导致受侵犯神经节内神经细胞变性、坏死;二是皮肤的水泡。迅速抑制神经节和相应的感觉神经纤维的充血、水肿和坏死,防止粘连形成,达到迅速镇痛、改善皮损,缩短病程及防止后遗症的发生是治疗的关键。因而,尽早明确诊断,     

Estimation of accumulated dose of radiation by method of ESR-spectrometry of dental enamel of mammals

ESR-spectrometry was used to investigate radiation-induced paramagnetic centers in enamel of mammals: carnivores (polar bear and fox), ungulates (reindeer, European bison, moose), and man. Values at half the microwave power saturation of the radiation signal, P_1/2, evaluated at room temperature, was found to range from 16 to 26 mW for animals and man. A new approach to discrimination of the radiation induced signal from the total ESR spectrum of reindeer enamel is proposed. ‘Dose-response’ dependencies of enamel of different species mammals were measured within the dose range from 0.48 up to 10.08 Gy. Estimations of ‘radiosensitivity’ enamel of carnivores and ungulates showed good agreement with radiosensitivity enamel of man by ESR method.     

Analysis of the results of the international comparison of activity measurements of a solution of Fe

The results of an international comparison of activity measurements of a solution of ⁵⁵Fe organized by the BIPM in 2005 are reported and analysed. This exercise, which follows the procedures of the CIPM mutual recognition arrangement to update older comparisons, is a renewal of the comparison organized by the BIPM that took place in 1978. A EUROMET comparison was organized in 1996 specifically to compare activity measurements of a ⁵⁵Fe solution by means of liquid-scintillation techniques. Results of these three comparisons are presented and discussed in this paper.

The radionuclide solution was provided by the NPL, which also distributed the samples to the participants. The activity of the ampoules was measured by 16 laboratories using 12 methods producing 25 results. Some general considerations on uncertainty assessments pertaining to the different techniques used are drawn. The outcome of four different estimators is compared from which the presence of at least one outlier can be confirmed. Further measurements should be made to try to reduce the discrepancy between the results. To date the outcome of the present comparison does not show an improvement to that of the 1996 comparison.     

Evaluation of the results of various technics of non-surgical therapy of varicocele

A new method of non-surgical treatment of varicocele syndrome is described: it consists in sclerotherapy of spermatic vein by trans-femoral percutaneous catheterization with balloon-catheters. In 8 cases venous thrombosis has been induced by direct electric clotting. The techniques and a 6 months follow-up are discussed. It is pointed out that this procedure should be considered as the method of choice for tubular lesions and sub-fertility prophylaxis in young people and in childhood.     

延迟性脾破裂误漏诊原因分析

目的探讨延迟性脾破裂误漏诊原因和预防措施.方法回顾性分析总结12例延迟性脾破裂中的诊断和误漏诊的经验与教训.结果本组延迟性脾破裂的误漏诊5例(41.66%).对多发伤与脾破裂并存可能认识不足,外伤史轻微或伤员隐瞒外伤史,缺乏腹痛-缓解-突然再腹痛的典型病史,缺乏“对冲性脾破裂”力学分析和整体化诊断思路等为其误漏诊的主要原因.结论详细的外伤史和全面系统检查,重视腹以外多发伤掩盖腹内脏器伤及延迟性脾破裂可能.确立外伤-腹内脏器伤-脾破裂整体化诊断思路.不间断地辅以B超检查脾形态学变化和腹内有无积液,腹腔穿刺确定有无血腹、X线胸腹部检查观察左侧胸肋角和膈肌运动情况、必要时CT检查以尽早发现脾包膜下血肿,降低延迟性脾破裂误漏诊率.