1、Intestinal ObstuctionHua-dan Xue 2008-11-30Ileus (intestinal obstruction)Mechanical intestinal obstructionSimple obstruction：occlusion/constriction of bowel lumenStrangulated obstruction：impaired blood supply of obstructed segmentIleus (adynamic/non-obstructive) Paralytic & spasmDerangement impairin

2、g proper distal propulsion of intestinal contentsCautions to barium exam due to the possibility of obstruction aggravating Classification - locationGastric outlet obstruction: Only one/two air-fluid levelsHomogeneous mass displacing transverse colonDuodenal obstruction: Double-bubble sign; Frequentl

3、y normal due to absence of gas from vomitingClassification - locationJejunal and ileal obstruction: Candy cane: 3 loops+3cm gas-fluid levels+35 hours onsetDisparity in size between obstructed and normal loopsLittle/no gas + stool in colon with complete mechanical obstruction after 12-24 hoursSteplad

4、der appearance; string-of-bead;Cave: fluid-distended loops may lead one to overlook obstruction!Mechanical obstructionClassification - locationColonic obstructionDilated colon onlyDilated small bowel (incompetent ileo-cecal valve)Gas-fluid levels distal to hepatic flexure (fluid is normal in cecum a

5、nd ascending colon)Cecum most dilated portion (10cm will be critical)Classification locationLocalized ileusCauses: often associated with adjacent acute inflammatory process (acute pancreatitis, acute appendicitis, etc.)Sentinel loop: loops near the local peritonitisClosed-loop obstructionClosed-loop

6、 obstructionClosed-loop obstructionFixation of bowel loop:Coffee bean sign: gas filled loopPseudo-tumor: fluid-filled loopU-shaped dilated bowel loopIncreasing intra-luminal fluidBeak sign: point of obstructionWhirl sign: twisting of bowelClosed-loop obstructionLarge volvulusBeak signClassification

7、- etiology機(jī)械性腸梗阻單純性腸梗阻：腸管通暢性障礙絞窄性腸梗阻：腸管通暢性障礙伴有血運(yùn)障礙動(dòng)力性腸梗阻麻痹性腸梗阻：痙攣性腸梗阻：血運(yùn)性腸梗阻：腸系膜動(dòng)脈血栓或栓塞所致 鋇劑造影須慎重使用，鋇劑吸收水分會(huì)加重梗阻單純性腸梗阻階梯狀氣液平大跨度腸袢魚肋征絞窄性腸梗阻Strangulated obstructionTriad: closed-loop obstruction of the involved segment (majority of cases)Mechanical obstruction proximal to the involved segmentVenous con

8、gestion of the involved loopAbdominal plain film :signs for volvulus（腸扭轉(zhuǎn)） or closed-loop obstruction + bowel thickeningCT has 63%100% detection rate!Poor/no enhancement of bowel wallMesenteric haziness due to edema絞窄性腸梗阻假腫瘤征：兩端閉鎖的絞鎖腸段內(nèi)充滿大量液體，仰臥位呈腫塊影，而站立位或側(cè)臥位水平位片上則在該腫瘤塊影上部見(jiàn)一短小的液面 咖啡豆征：閉襻小跨度蜷曲腸襻：腸系膜增厚

9、縮短長(zhǎng)液面征：張力低、血性液體空回腸換位征：小腸扭轉(zhuǎn)腸扭轉(zhuǎn)小腸扭轉(zhuǎn)：空回腸換位、花瓣樣或香蕉樣排列 麻痹性腸梗阻Ileus Causes: postoperativeintraabdominal inflammationischemic bowel diseaseLarge + small bowel gastric distensionDecreased small bowel distension in serial filmsDelayed but free passage of contrast materialStrangulated obstructionTriad: Closed

10、-loop obstruction of the involved segment (majority of cases)Mechanical obstruction proximal to the involved segmentVenous congestion of the involved loopAbdominal plain film :Signs for volvulus or closed-loop obstruction + bowel thickeningCT has 63%100% detection rate!Poor/no enhancement of bowel w

11、allMesenteric haziness due to edemaComparison - Simple obstructionStepladder gas-fluid levelLarge span loopFish-rib appearanceComparison - Strangulated obstructionPseudo-tumorCoffee bean sign：closed loopSmall span loop：shortening of mesentery Long gas-fluid level：low tensionDisplacement of jejunum a

12、nd ileumVolvulusSmall intestine volvulus：displacement of ileum and jejunum, banana-like flower-leaves-like form (representing the twisting bowel) Ileus (paralytic )Causes: PostoperativeIntra-abdominal inflammationIschemic bowel diseaseLarge + small bowel gastric distensionDecreased small bowel diste

13、nsion in serial filmsDelayed but free passage of contrast materialFinding the reasonsPost-operationInfectionIntussusception Thrombosis Tumor (extrinsic and intrinsic bowel)CongenitalIntestinal obstructionModalities, Methods and indications 1、Plain abdominal film：acute perforation and obstruction of bowel2、Barium enema：diagnose and therapy of obstructive disorders, e.g. intussusception, volvulus 3、CT scan：all kinds o