三维动态增强磁共振血管成像在肝移植术前的应用

 目的探讨三维动态增强磁共振血管成像(3D DCE MRA)三期扫描技术,评价其在肝移植术前的诊断价值.方法对拟进行肝移植的183例患者进行术前3D DCE MRA成像扫描,采用Siemens Symphony 1.5T超导MRI扫描机,圆形极化相控阵体线圈,3D DCE MRA三期(动脉期、门脉期和静脉期)扫描技术,即对所得图像进行综合评价.结果全部病例均获得了满意的血管成像图像,肝动脉可显示2～3级分支,门静脉可显示2～5级分支,肝静脉可显示1～2级分支.183例肝移植患者,5例显示肝动脉变异,其中2例起自肠系膜上动脉,2例直接起自腹腔干,1例起自胃左动脉.单纯肝硬化门脉高压103例,其中,冠状静脉和食道胃底静脉曲张23例、脐周静脉曲张5例、肠系膜静脉曲张2例、脾门周围静脉曲张30例,门静脉玻璃样变性1例;原发性肝癌79例,5例肝动脉包埋、僵直、推移,2例肝内动-静脉瘘,门静脉右支癌栓23例,门静脉左支癌栓7例,门静脉主干癌栓3例,同时发生门静脉左右支癌栓的2例,MRA表现为门静脉呈半月形或杯口形缺损或不显影.7例肝静脉出现栓塞,5例下腔静脉受压推移,1例下腔静脉瘤栓.结论 3D DCE MRA三期扫描能很好的显示肝动脉、门静脉、肝静脉及下腔静脉系统病变,肝移植术前应用3D DCE MRA,基本达到临床要求,是术前血管评估的有效方法.     

MRI在肝移植中的应用

目的评价MRI检查在肝移植术前术后的应用价值。方法将我院2004-01—2005-03收治的22例肝移植患者术前MRI检查结果与手术、病理检查相比较,术后MRI检查与其它影像学检查相比较。结果22例肝移植患者中,肝硬化并门脉高压15例,肝硬化、肝癌6例,严重肝损伤1例;门静脉栓子5例,其中4例为癌栓,1例是管壁样组织,肝右静脉及下腔静脉瘤栓1例;副肝动脉2例,分别发自腹腔干及肠系膜上动脉;胆管吻合口狭窄或胆漏3例;肝动脉可显示2~3级分支,门静脉可显示2~4级分支,肝静脉可显示1~2级分支,胆管显示2~3级分支。结论MRI对肝移植术前和术后的评估具有很大的价值。     

门脉高压的三维增强磁共振血管成像

目的 探讨上腹部磁共振对比增强三维血管成像技术(three-dimensional contrast-enhanced MR angiography,3D CE-MRA),对显示门脉高压所致血管改变及血流改变的应用价值.方法 对60例门脉高压患者,运用GE Signa 1.5T超导磁共振扫描仪进行3D CE-MRA 和2D CE-MRA成像,分析门脉高压的MRA表现.结果 (1)门静脉纤细狭窄18例.(2)门静脉闭塞、海绵样变11例.(3)食管下段、胃底静脉曲张43例.(4)腔静脉狭窄、闭塞 11例.(5)奇静脉、半奇静脉开放4例.(6)脐静脉开放4例.结论 3D CE-MRA是诊断门脉高压所致门脉系统血管及血流改变的可靠方法.     

肝硬化患者CT门静脉血管成像中门静脉侧支血管的表现

目的 分析肝硬化患者在16排螺旋CT门静脉血管成像(CTPV)上门静脉侧支血管的表现.方法 对36例经临床、肝功能和影像学检查诊断为肝硬化门静脉高压的患者行腹部CTPV检查,经图像后处理,获得门静脉系统及侧支血管三维重建图像.结果 CTPV可以直观地显示门静脉系统及整个门静脉侧支循环系统.36例病例中显示胃左静脉曲张29例(80.6%),食管下段静脉曲张18例(50.0%),胃短/W后静脉曲张15例(41.7%),食管旁静脉曲张9例(25.0%),胃-肾/脾-肾分流8例(22.2%),门静脉海绵样变7例(19.4%),脐静脉与腹壁静脉曲张6例(16.7%),椎旁静脉分流4例(11.1%).结论 CTPV能很好地显示肝硬化患者门脉高压侧支循环的开放部位、范围及严重程度,对判断病情、选择治疗方案及估计预后有重要的临床应用价值.     

肝细胞癌门静脉癌栓致门静脉海绵样变性侧支循环的螺旋CT研究

目的：探讨肝细胞癌门静脉癌栓所致门静脉海绵样变性（cavernous transformation of the portal vein,CaTPV)侧支循环血管的构成及螺旋CT特征。资料与方法：搜集经组织病理学证实的肝细胞癌伴门静脉主干癌栓57例进行回顾性分析，根据病理所见有无肝硬化背景分为肝硬化阳性组（n=26)和肝硬化阴性组（n=31);另选择15例肝硬化合并门静脉高压而无肝细胞癌和CaTPV的病例作为对照组。所有病例均行标准化上腹部螺旋CT双期增强扫描。观察CaTPV侧支血管的CT表现，对比分析各组螺旋CT对CaTPV侧支血管的显示率。结果：门静脉胆支（胆囊静脉和胆管周围静脉丛）和胃支（胃左、胃右静脉及属支）是CaTPV最常显示的侧支血管。门静脉胆支的出现与CaTPV有关，而与肝硬化、门静脉高压无关（CT显示率81％－94％比0）；门静脉胃支的CT显示率3组之间无差别（胃左静脉77％－87％，胃右静脉58％－60％）。结论：门静脉胆支和胃支是构成CaTPV侧支循环的最主要的血管；胆支开放仅见于CaTPV，而胃支开放与肝硬化开发门静脉高压以及CaTPV均有关系。二者在CaTPV造成的血液动力学改变中可能发挥不同的作用。     

肝硬化门静脉高压侧枝血管的多层螺旋CT表现

目的用多层螺旋CT(MSCT)统计、分析肝硬化门静脉高压患者的侧枝循环表现。方法收集203例肝硬化门静脉高压患者MSCT上腹部检查的完整资料。结果共发现门静脉侧枝或异常血管612处:食管下段静脉曲张175处,食管旁静脉曲张49处(其中伴假肿瘤征13处),胃底静脉曲张119处,胃冠状静脉曲张105处,胃肾静脉分流34处,脾肾静脉分流15处,椎旁静脉丛曲张16处,脐静脉再通48处,副脐静脉再通22处,脐静脉、副脐静脉同时再通4处,腹壁静脉丛曲张呈蛇头征12处,门静脉海绵样变8处,门静脉右后支瘤样扩张并与下腔静脉分流4处,胃左静脉直接入肝与门静脉左支相连1处。结论MSCT可较好地显示各类门静脉高压侧枝,了解这些异常表现有助于作出正确诊断,避免误诊,对临床选择治疗方法有重要的意义。     

胃左静脉MSCTA预测肝硬化门静脉高压食管胃底静脉曲张破裂岀血的价值

目的探讨胃左静脉多层螺旋CT血管造影(MSCTA)预测肝硬化门静脉高压食管胃底静脉曲张破裂岀血的临床应用价值。资料与方法应用16层螺旋CT对74例肝硬化门静脉高压症患者和200名正常对照者行上腹部增强扫描,采用多平面重组(MPR)、最大密度投影(MIP)对胃左静脉进行血管重组,观察胃左静脉和食管胃底静脉曲张情况,并测量胃左静脉最大内径进行统计学分析。结果总体肝硬化门静脉高压组胃左静脉最大内径与正常对照组比较明显增宽(P=0.00),肝硬化门静脉高压出血组、未出血组胃左静脉最大内径与正常对照组比较均显著增宽,差异具有统计学意义(P<0.05)。以胃左静脉最大内径7.0 mm为判断岀血的标准,其敏感性、特异性、准确性分别为61.5%、77.1%、71.6%。结论 MSCTA可以清晰显示胃左静脉和食管胃底静脉曲张情况;胃左静脉增宽是肝硬化门静脉高压食管胃底静脉曲张破裂出血的一个危险因素,胃左静脉内径的测量对食管胃底静脉曲张破裂岀血具有一定的预测价值。     

三维动态增强磁共振门静脉造影对门静脉癌栓的诊断价值

目的 :探讨三维动态增强磁共振门静脉造影 ( 3DDCE MRP)对门静脉癌栓的诊断价值。方法 :对 2 6例门静脉癌栓患者行 3DDCE MRP检查 ,观察其门静脉癌栓在 3DDCE MRP上的表现 ,并与常规MRI表现进行比较。结果 :所有 2 6例门静脉显示满意。 3DDCE MRP均显示了癌栓所致相应部位门脉阻塞征象 ,2 1例示肝门部侧支血管 ,形成门静脉海绵样变性。结论 :3DDCE MRP是诊断门静脉癌栓的有效方法 ,尤其在显示由此引起的侧支循环方面有很大优越性。不足在于不能显示癌栓近侧端的范围     

三维增强磁共振血管成像在肝移植中的临床应用

目的:探讨三维增强磁共振血管成像(3D CE-MRA)对原位肝移植(OLT)出入肝脏的血管进行术前评估及术后监测的价值.方法:回顾性分析我院肝移植患者术前20例及术后13例患者的3D CE-MRA图像,包括血管主干及其分支的显示、癌栓及血管狭窄的情况.结果:所有患者3D CE-MRA检查均获成功,其MRI图像重组后可以很好地显示肝动脉、肝静脉、门静脉及下腔静脉的走行、癌栓及血管变异情况.结论:3D CE-MRA具有无创、安全、快捷、准确、无辐射等优点,是原位肝移植术前评估及术后监测的首选检查方法.     

MDCTP对肝硬化门脉高压侧支循环血管的显示价值

目的:评价16排螺旋CT门静脉血管成像(MDCTP)技术在显示肝硬化门脉高压侧支循环血管方面的应用价值。方法:对38例临床诊断肝硬化门脉高压的患者行上腹部MDCTP检查。采用MIP、MPR、VR等三维重组技术进行图像后处理,获得门静脉系统及侧支循环血管图像。结果:38例中显示食管胃底粘膜下静脉曲张31例,食管旁静脉曲张10例;胃左静脉曲张29例,胃短静脉曲张26例;脐静脉与腹壁静脉曲张7例;脾-肾或胃-肾分流6例;腹膜后分流2例。结论:MDCTP能显示肝硬化患者门-体侧支循环开放部位、范围及程度,有重要的临床应用价值。     

MRA在腹部静脉的应用

目的：评价常规ＭＲＡ和动态增强ＭＲＡ在腹部静脉检查中的价值。材料与方法：腹部静脉ＭＲＡ共５７例行５９人次检查。包括２Ｄ ＴＯＦ５１次，２Ｄ ＰＣ１９次，动态增强ＭＲＡ３０次（其中２Ｄ动态增强１０次，３Ｄ动态增强２０次）。５７例中门脉高压者１８例，布加氏综合征８例，门腔静脉分流术前或术后检查６例，原发性和转移性肝癌９例，其他病变６例，正常组１０例。结果：本组ＭＲＡ表现分别为门脉增粗和静脉曲张；下腔静     

3D CE-MRA在评价腹部静脉系统中的应用

目的探讨三维增强磁共振血管成像（3DCE—MRA）技术在腹部静脉系统中的应用价值。方法收集具有完整资料的16例病例，先行常规MRI检查，随后经静脉注射Gd—DTPA20—30mL后连续三次行3DCE—MRA采集数据，对静脉系统原始图像进行MIP重建。主要观察指标为下腔静脉、脾静脉、肝静脉、肠系膜上静脉、门静脉形态变化。结果16例患者中，门腔静脉正常者9例，3DCE—MRA清晰显示下腔静脉、肝静脉、脾静脉、肠系膜上静脉、门静脉结构；门静脉高压3例，示脾静脉增宽迂曲，门静脉主干增宽及明显侧支循环形成；2例布加氏综合征；1例下腔静脉血栓形成；1例门静脉海绵样改变。结论3DCE—MRA是一种安全、敏感性高的血管造影技术，可提高腹部静脉系统疾病的术前诊断。     

Noncontrast 3D steady state free precession magnetic resonance angiography of the thoracic central veins using nonselective radiofrequency excitation over a large field of view: initial experience

PURPOSE: To evaluate the feasibility of three-dimensional (3D) steady state free precession (SSFP) magnetic resonance angiography (MRA) using nonselective radiofrequency excitation for the assessment of thoracic central veins. MATERIALS AND METHODS: Thirty consecutive patients (17 males, 13 females, age range 22-76) with various cardiac and thoracic vascular diseases underwent free-breathing electrocardiogram-gated noncontrast SSFP MRA and conventional high-resolution 3D contrast-enhanced (CE) MRA of the thorax at 1.5 T. Two readers evaluated both datasets for findings: venous visibility and sharpness (from 0, not visualized to 3, excellent definition); artifacts; signal-to-noise ratio (SNR); and contrast-to-noise ratio (CNR) in 8 venous segments including superior vena cava (SVC), supra-diaphragmatic inferior vena cava, bilateral brachiocephalic, proximal subclavian, and lower internal jugular veins. Statistical analysis was performed using Wilcoxon test for overall image quality and vessel visibility, t test for SNR and CNR analysis, and kappa coefficient for inter-observer variability. RESULTS: 3D SSFP and CE-MRA were successfully performed in all patients. Scan time for SSFP MRA ranged from 5 to 10 minutes (mean +/- standard deviation, 7 +/- 2 minutes). Reader 1 (2) graded the overall image quality as excellent and good on SSFP MRA in 23 (25) and 7 (5) patients, and on CE-MRA in 22 (23) and 8 (9) patients, respectively. On SSFP MRA, readers 1 and 2 graded 234 (97.5%) and 233 (97.1%) venous segments with diagnostic definition (grades 2 and 3) (kappa = 0.69), respectively. On conventional CE-MRA, readers 1 and 2 graded 231 (96.3%) and 232 (96.7%) venous segments with diagnostic definition (grades 2 and 3) (kappa = 0.68), respectively. Segmental visibility and sharpness were higher for lower internal jugular veins on CE-MRA for each reader (P < 0.001). No significant difference existed for venous visibility and sharpness scores for other venous segments between the 2 techniques for both readers (P > 0.05). SNR and CNR values were lower for internal jugular veins on SSFP MRA (P < 0.001). No significant difference existed between SNR and CNR values for the other venous segments on SSFP and CE-MRA (P > 0.05 for all). The 2 readers demonstrated patent SVC Glenn shunt to main pulmonary artery (n = 3), patent extra cardiac Fontan shunt from inferior vena cava to pulmonary artery confluence (n = 2), and dilatation and thrombosis of SVC (n = 1) and right brachiocephalic vein (n = 1) on both datasets. CONCLUSION: Free breathing navigator-gated noncontrast 3D SSFP MRA with nonselective radiofrequency excitation provides high image quality and sufficient SNR and CNR for confident evaluation of thoracic central veins.     

Portal venous stent placement in patients with pancreatic and biliary neoplasms invading portal veins and causing portal hypertension: initial experience.

PURPOSE: To evaluate the clinical usefulness of portal venous stent placement in patients with pancreatic or biliary neoplasms invading portal veins and causing portal hypertension. MATERIALS AND METHODS: Thirteen patients underwent portal venous stent placement because of gastrointestinal bleeding (n = 8), risk of gastroesophageal varix rupture (n = 4), ascites (n = 4), thrombocytopenia (n = 3), and/or portal venous thrombosis (n = 3). The main portal vein or both the intrahepatic and main portal veins were invaded in six patients (group A). The main portal vein and splanchnic veins were involved in seven patients (group B). Stents were placed across the stenotic (n = 8) or occluded (n = 5) lesions after percutaneous transhepatic portography. Changes in portal venous pressure, stent patency, and survival were evaluated. RESULTS: Mean portal venous pressure decreased significantly immediately after stent placement, from 24.9 mm Hg +/- 5.9 (SD) to 15.8 mm Hg +/- 4.6 (P <.001). In group A, blood flow through the stent was maintained and the symptoms had subsided at follow-up (mean, 12.5 months). In group B, symptoms were improved in five patients, but the stents were occluded in all but one patient at a mean follow-up of 1.5 months. There was a significant difference in stent patency between the patients with (14%) and those without (100%) splanchnic venous involvement (P <.01). CONCLUSION: Stent placement helped to relieve portal hypertension symptoms. Splanchnic venous involvement was associated with worse stent patency.     

CT features of abdominal manifestations of primary antiphospholipid syndrome.

PURPOSE: The purpose of this work was to evaluate the CT features of the abdominal manifestations of primary antiphospholipid syndrome (PAPS). METHOD: Of the 32 patients who were confirmed to have PAPS among 751 patients with elevated antiphospholipid antibodies during a 2 year period, we retrospectively reviewed the 14 patients who underwent abdominal CT. The clinical indications for abdominal CT included abdominal pain, abdominal distension, or lower leg swelling. CT findings were analyzed with regard to the abdominal vascular system and abdominal organ involvement patterns as well as ancillary findings. RESULTS: Of the 14 patients with PAPS, 10 had involvement of the venous system (72%), 2 of the arterial system (14%), and 2 of both systems (14%). Of the 12 patients who had venous system involvement, 4 had thrombosis in the inferior vena cava (IVC), 2 in both the IVC and the hepatic vein, 1 in the IVC and splenic and portal veins, 1 in the IVC and hepatic and adrenal veins, 1 in the hepatic, portal, and renal veins, and 3 in the portal and superior mesenteric veins. Budd-Chiari syndrome developed in five of the nine patients who had thrombosis of the IVC or hepatic vein. Arterial thrombosis was noted in four patients, hepatic artery in two, aorta in one, renal artery in one, pancreatic arcade in one, and splenic artery in one, with infarct of multiple organs including the liver, jejunum, colon, kidney, and adrenal gland. Seven of the 14 patients (50%) manifested thrombosis or infarct of multiple extra-abdominal organs. CONCLUSION: PAPS should be included in the differential diagnosis when CT demonstrates infarcts in multiple organs or patients have recurrent episodes of venous or arterial thrombosis.     

Calcifications in the portal venous system: comparison of plain films, sonography, and CT.

We describe 10 patients with long-standing portal hypertension and calcifications in the splenoportal and mesenteric venous systems or collateral vessels. The patients were examined with abdominal plain films (n = 10), sonography (n = 10), and CT (n = 9). Calcium was seen on CT scans in nine cases, on sonograms in seven, and on abdominal plain films in five. Calcifications appeared to be located in the wall of the vein in all cases. Sites of detection included the main portal, splenic, superior mesenteric, coronary, and peripancreatic veins. CT was more sensitive than sonography, and both were more sensitive than plain films, in showing portal venous calcification. Detection of such calcifications may influence surgical or percutaneous therapy of portal hypertension.     

动态增强磁共振门静脉造影在门脉高压症诊断中的价值

目的:探讨动态增强磁共振门静脉造影(DCE MRP)在门脉高压症诊断中的价值。方法:对门脉高压症组23例和正常对照组15例行DCE MRP检查。观察23例门静脉高压症在DCE MRP上的表现。结果:对照组15例均清楚显示门静脉。门脉高压症表现为门静脉增粗(21例)、脾静脉迂曲扩张(23例);门静脉分支级数减少(18例);门静脉延迟显影(7例);显示侧枝循环静脉(6例);门静脉血栓形成(3例)。结论:DCE MRP是评价门静脉的一项快速无创的技术,可准确显示门静脉高压症门静脉系统的病理改变。     

多层螺旋CT门静脉成像对门脉高压侧支循环血管的研究

目的:评价多层螺旋CT门静脉成像(MDCTP)在门脉高压侧支循环血管显示中的价值。方法:31例经临床检查确诊的门静脉高压患者行MDCTP检查,采用MIP、MPR、VR等重建技术进行图像后处理,获得门静脉系统及侧支血管图像,两名医师分别判断侧支血管显示情况。结果:MDCTP不仅显示肝内门静脉3~4级分支,还显示了整个门脉侧支血管系统。31例患者中,胃左静脉曲张28例,食管或食管旁静脉曲张27例,脾静脉曲张21例,胃短/胃后静脉曲张7例,脾-肾分流血管1例,脐静脉曲张伴腹壁静脉曲张2例,门静脉栓塞4例,肠系膜上静脉血管闭塞2例。结论:MDCTP能显示门静脉高压侧支血管开放的部位、范围及程度,有助于对门脉高压患者治疗方案的选择,是一种有重要临床价值的无创性门脉检查方法。     

螺旋CT门静脉血管造影的临床应用价值

目的 :评价螺旋CT门静脉血管造影 (CTP)的临床应用价值。材料和方法 :对 10 8例对疑有肝脏疾病的患者分别行最大强度投影 (MIP)和表面遮盖法 (SSD)CTP成像。结果 :MIPCTP能同时显示 4级以上门静脉分支和 2级以上的肝静脉分支。CTP能直观地评价门静脉和肝静脉的位置、管径、有无门静脉受侵或癌栓形成 ,了解门解脉高压侧支循环的分布范围和程度。CTP有助于经颈静脉肝内门腔静脉分流术 (TIPS)术前定位、Budd Chiari综合症的诊断和术后随访。SSDCTP立体感强 ,但不利于细微结构和癌栓的显示。结论 :CTP是门静脉和肝静脉无创性检查的可靠方法 ,有较高的临床应用价值。