小肠结核的影像诊疗及鉴别诊疗VIP免费

小肠结核的影像诊断小肠结核的影像诊断及鉴别诊断及鉴别诊断福建医科大学附属第一医院王志敏2015-09-26概述肠结核(IntestinalTuberculosis)是临床上较为常见的肺外结核病。由结核杆菌侵犯肠道而引起绝大多数继发于肠外结核,特别是开放性肺结核好发于青壮年常与腹膜结核和肠系膜淋巴结结核同时存在病因含结核分枝杆菌的肠内容物在回盲部停留时间较久，增加了局部肠黏膜感染的机会结核分枝杆菌易侵犯淋巴组织，而回盲部有丰富的淋巴组织病因发展中国家：人口密集发达国家：移民和AIDS糖尿病、慢性肾病、霍奇金淋巴瘤、慢性肺疾病、营养不良、酗酒、长期免疫抑制治疗者、长期激素治疗者均可增加发病率好发部位肠结核好发于回盲部其他部位依次为升结肠、空肠、横结肠、降结肠、阑尾、十二指肠和乙状结肠等，少数鉴于直肠，偶见于胃和食管感染途径肠源性：肠结核患者原有开放性肺结核，因经常吞咽含有结核菌的自身痰液而继发感染血源性：血行播散也是肠结核的感染途径之一，见于粟粒型结核经血行播散而侵犯肠道直接蔓延：可由腹腔内结核病灶直接蔓延，如输卵管结核、结核性腹膜炎、肠系膜淋巴结核病理分型溃疡型肠结核：肠壁淋巴组织呈充血、水肿及炎症渗出性病变，进一步发展为干酪样坏死，随后形成溃疡增生型肠结核：多局限于回盲部，可有大量的结核肉芽肿和纤维组织增生混合型肠结核：兼有上述二者X线表现溃疡型肠结核：跳跃征局部病变肠管钡剂排空加快，几乎无钡剂停留且充盈不佳，病变上下两端肠段钡剂充盈良好进一步发展，病变部位黏膜增粗、紊乱，进而肠壁出现斑点状、锯齿状龛影病变后期，由于纤维组织增生及疤痕挛缩，使受累回肠末端、盲肠及回盲瓣变窄、变形、缩短。呈现所谓的“一字征”，较具特征性增殖型结核主要表现为管腔狭窄及缩短变形，并多发息肉样充盈缺损单纯性增殖结核，激惹征多不明显；若伴有溃疡时，则可有激惹征由于粘膜下层及浆膜下纤维组织增生，肠壁增厚致肠管狭窄，重者可出现近段回肠扩张回盲瓣受侵时，表现为增生肥厚CoronalreconstructedplainCT:multiplesmallbowelsegmentsshowingmildlythickenedwall.b,cAxT2fatsuppressed:Thickenedsmallbowelwallshowingisointensesignalintensity.d,eAxcontrast-enhancedT1fatsuppressed:EnhancingthickenedsmallbowelwallRetrogradedouble-contraststudyoftheterminalileum.Aswollenileocecalvalvecausingnarrowingoftherevalvularsegmentoftheterminalileumisseen.Superficiallongitudinalulcersareseenintheterminalileum,andthereismarkedlymphoidhyperplasiainthedistalpartoftheileum.Inthetransverseanddescendingcolonseveralgirdleulcerswithatendencytoproducesymmetricalstenosesareseenasskiplesions.B：Close-upviewofthetransversecolon.Confluenceofsuperficialandirregularulcerscreatingawholegirdleulcer.MSCT及MRI对肠结核的诊断价值可发现肠结核段肠管壁明显增厚，增强扫描病变段肠壁明显增强如并发腹腔淋巴结结核者，还可见肿大淋巴结呈环状增强；肠系膜淋巴结肿大、钙化肠结核可侵犯肠管周围组织，引起结核性炎症或结核性肉芽组织及干酪样坏死组织的出现，平扫可表现为周围脂肪浑浊，密度增高。伴有干酪样坏死组织时密度不均匀，周边明显强化a:Corcontrast-enhancedCT:mildlynhancingcircumferentialsignal.c,dCorPre-contrastT1weightedandcontrast-enhancedT1fatsuppressed:Thickenedcecalwallshowingisointensesignal,whichshowspostcontrastenhancementinsamepatientasin(a).TheenhancementonMRIhasmuchbettervisibilitycomparedtoCTTerminalilealstricture.a–hDynamicBalancedTurboFieldEcho(BTFE)[cineMRI]:Fewofmultiplesequentialimages,takenatthesamepositioninrealtime,showingterminalilealstricture(arrow)withproximaldilatedsmallbowelloopshowingalternaterelaxationandcontraction.Ilealstrictureshowednorelaxation.iCorT2weighted:terminalilealstricture.hCorcontrast-enhancedT1fatsuppressed:Enhanc...