intestinal obstuction
DESCRIPTION
Intestinal Obstuction. Hua-dan Xue 2008-11-30. Ileus (intestinal obstruction). Mechanical intestinal obstruction Simple obstruction : occlusion/constriction of bowel lumen Strangulated obstruction : impaired blood supply of obstructed segment Ileus (adynamic/non-obstructive) - PowerPoint PPT PresentationTRANSCRIPT
Intestinal ObstuctionIntestinal ObstuctionHua-dan Xue Hua-dan Xue 2008-11-302008-11-30
Ileus Ileus (intestinal obstruction)(intestinal obstruction)
Mechanical intestinal obstructionMechanical intestinal obstruction– Simple obstructionSimple obstruction :: occlusion/constriction oocclusion/constriction o
f bowel lumenf bowel lumen– Strangulated obstructionStrangulated obstruction :: impaired blood simpaired blood s
upply of obstructed segmentupply of obstructed segment Ileus (adynamic/non-obstructive) Ileus (adynamic/non-obstructive)
– Paralytic & spasmParalytic & spasm– Derangement impairing proper distal propulsiDerangement impairing proper distal propulsi
on of intestinal contentson of intestinal contents
Cautions to barium exam due to the possibility of obstruction aggravating
Classification - locationClassification - location
Gastric outlet obstruction: Gastric outlet obstruction: – Only one/two air-fluid levelsOnly one/two air-fluid levels– Homogeneous mass displacing Homogeneous mass displacing
transverse colontransverse colon Duodenal obstruction: Duodenal obstruction:
– Double-bubble sign; Double-bubble sign; – Frequently normal due to absence of Frequently normal due to absence of
gas from vomitinggas from vomiting
Classification - locationClassification - location
Jejunal and ileal obstruction:Jejunal and ileal obstruction: – Candy cane: >3 loops+>3cm gas-fluid leCandy cane: >3 loops+>3cm gas-fluid le
vels+>3~5 hours onsetvels+>3~5 hours onset– Disparity in size between obstructed anDisparity in size between obstructed an
d normal loopsd normal loops– Little/no gas + stool in colon with complLittle/no gas + stool in colon with compl
ete mechanical obstruction after 12-24 ete mechanical obstruction after 12-24 hourshours
– Stepladder appearance; string-of-bead;Stepladder appearance; string-of-bead;Cave: fluid-distended loops may lead one to overlook obstruction!!!
Mechanical Mechanical obstructionobstruction
Classification - locationClassification - location
Colonic obstructionColonic obstruction– Dilated colon onlyDilated colon only– Dilated small bowel (incompetent ileo-cDilated small bowel (incompetent ileo-c
ecal valve)ecal valve)– Gas-fluid levels distal to hepatic flexure Gas-fluid levels distal to hepatic flexure
(fluid is normal in cecum and ascending (fluid is normal in cecum and ascending colon)colon)
– Cecum most dilated portion (>10cm will Cecum most dilated portion (>10cm will be critical)be critical)
Classification – Classification – locationlocation Localized ileusLocalized ileus
– Causes: often associated with adjacent Causes: often associated with adjacent acute inflammatory process (acute panacute inflammatory process (acute pancreatitis, acute appendicitis, etc.)creatitis, acute appendicitis, etc.)
Sentinel loop: loops near the local pSentinel loop: loops near the local peritonitiseritonitis
Closed-loop obstructionClosed-loop obstruction
Closed-loop Closed-loop obstructionobstruction Closed-loop obstructionClosed-loop obstruction
– Fixation of bowel loop:Fixation of bowel loop: Coffee bean sign: gas filled loopCoffee bean sign: gas filled loop Pseudo-tumor: fluid-filled loopPseudo-tumor: fluid-filled loop U-shaped dilated bowel loopU-shaped dilated bowel loop
– Increasing intra-luminal fluidIncreasing intra-luminal fluid– Beak sign: point of obstructionBeak sign: point of obstruction– Whirl sign: twisting of bowelWhirl sign: twisting of bowel
Closed-loop obstructiClosed-loop obstructiononLarge volvulusLarge volvulus
Beak signBeak sign
Classification - Classification - etiologyetiology 机械性肠梗阻机械性肠梗阻
– 单纯性肠梗阻:肠管通畅性障碍单纯性肠梗阻:肠管通畅性障碍– 绞窄性肠梗阻:肠管通畅性障碍伴有血运障碍绞窄性肠梗阻:肠管通畅性障碍伴有血运障碍
动力性肠梗阻动力性肠梗阻– 麻痹性肠梗阻:麻痹性肠梗阻:– 痉挛性肠梗阻:痉挛性肠梗阻:
血运性肠梗阻:肠系膜动脉血栓或栓塞所致 血运性肠梗阻:肠系膜动脉血栓或栓塞所致
钡剂造影须慎重使用,钡剂吸收水分会加重梗阻
单纯性肠梗阻单纯性肠梗阻 阶梯状气液平阶梯状气液平 大跨度肠袢大跨度肠袢 鱼肋征鱼肋征
绞窄性肠梗阻绞窄性肠梗阻Strangulated obstructionStrangulated obstruction
TriadTriad: : – closed-loop obstruction of the involved segmeclosed-loop obstruction of the involved segme
nt (majority of cases)nt (majority of cases)– Mechanical obstruction proximal to the involvMechanical obstruction proximal to the involv
ed segmented segment– Venous congestion of the involved loopVenous congestion of the involved loop
Abdominal plain filmAbdominal plain film : :– signs for volvulussigns for volvulus (肠扭转) (肠扭转) or closed-loop oor closed-loop o
bstruction + bowel thickeningbstruction + bowel thickening CT has 63%~100% detection rate!!!CT has 63%~100% detection rate!!!
– Poor/no enhancement of bowel wallPoor/no enhancement of bowel wall– Mesenteric haziness due to edemaMesenteric haziness due to edema
绞窄性肠梗阻绞窄性肠梗阻 假肿瘤征:假肿瘤征:
– 两端闭锁的绞锁肠段内充满大量液体,仰卧位呈肿块两端闭锁的绞锁肠段内充满大量液体,仰卧位呈肿块影,而站立位或侧卧位水平位片上则在该肿瘤块影上影,而站立位或侧卧位水平位片上则在该肿瘤块影上部见一短小的液面部见一短小的液面
咖啡豆征:闭襻咖啡豆征:闭襻 小跨度蜷曲肠襻:肠系膜增厚缩短小跨度蜷曲肠襻:肠系膜增厚缩短 长液面征:张力低、血性液体长液面征:张力低、血性液体 空回肠换位征:小肠扭转空回肠换位征:小肠扭转
肠扭转肠扭转
小肠扭转:空回肠换位、花瓣样或香蕉小肠扭转:空回肠换位、花瓣样或香蕉样排列 样排列
麻痹性肠梗阻麻痹性肠梗阻Ileus Ileus Causes: Causes:
– postoperativepostoperative– intraabdominal inflammationintraabdominal inflammation– ischemic bowel diseaseischemic bowel disease
Large + small bowel ±gastriLarge + small bowel ±gastric distensionc distension
Decreased small bowel disteDecreased small bowel distension in serial filmsnsion in serial films
Delayed but free passage of Delayed but free passage of contrast materialcontrast material
Strangulated Strangulated obstructionobstruction
TriadTriad: : – Closed-loop obstruction of the involved segmClosed-loop obstruction of the involved segm
ent (majority of cases)ent (majority of cases)– Mechanical obstruction proximal to the involvMechanical obstruction proximal to the involv
ed segmented segment– Venous congestion of the involved loopVenous congestion of the involved loop
Abdominal plain filmAbdominal plain film : :– Signs for volvulus or closed-loop obstruction + Signs for volvulus or closed-loop obstruction +
bowel thickeningbowel thickening CT has 63%~100% detection rate!!!CT has 63%~100% detection rate!!!
– Poor/no enhancement of bowel wallPoor/no enhancement of bowel wall– Mesenteric haziness due to edemaMesenteric haziness due to edema
Comparison Comparison - - Simple obstructionSimple obstruction
Stepladder gas-fluid levelStepladder gas-fluid level Large span loopLarge span loop Fish-rib appearanceFish-rib appearance
Comparison Comparison - - Strangulated obstructionStrangulated obstruction
Pseudo-tumorPseudo-tumor Coffee bean signCoffee bean sign :: closed loopclosed loop Small span loopSmall span loop :: shortening of shortening of
mesentery mesentery Long gas-fluid levelLong gas-fluid level :: low tensionlow tension Displacement of jejunum and ileuDisplacement of jejunum and ileu
mm
VolvulusVolvulus Small intestine volvulusSmall intestine volvulus ::
– displacement of ileum and jejunum, displacement of ileum and jejunum, – banana-like flower-leaves-like form (repbanana-like flower-leaves-like form (rep
resenting the twisting bowel) resenting the twisting bowel)
Ileus (paralytic )Ileus (paralytic )
Causes: Causes: – PostoperativePostoperative– Intra-abdominal Intra-abdominal
inflammationinflammation– Ischemic bowel diseaseIschemic bowel disease
Large + small bowel Large + small bowel ±gastric distension±gastric distension
Decreased small bowel Decreased small bowel distension in serial filmsdistension in serial films
Delayed but free passage Delayed but free passage of contrast materialof contrast material
Finding the reasons…Finding the reasons…
Post-operationPost-operation InfectionInfection Intussusception Intussusception Thrombosis Thrombosis Tumor (extrinsic and intrinsic bowel)Tumor (extrinsic and intrinsic bowel) CongenitalCongenital
Intestinal obstructionIntestinal obstruction
Modalities, Methods and indications Modalities, Methods and indications 11 、、 Plain abdominal filmPlain abdominal film :: acute perforation anacute perforation an
d obstruction of boweld obstruction of bowel22 、、 Barium enemaBarium enema :: diagnose and therapy of obdiagnose and therapy of ob
structive disorders, e.g. intussusception, volvulstructive disorders, e.g. intussusception, volvulus… us…
33 、、 CT scanCT scan :: all kinds of acute abdomen applicall kinds of acute abdomen applicable.able.
44 、、 B-usB-us :: solid organ trauma, peritoneal fluid csolid organ trauma, peritoneal fluid collection, localized abscess, calculi & obstructioollection, localized abscess, calculi & obstruction, intussusception, acute imflammation. n, intussusception, acute imflammation.
referencesreferences
Review manualReview manual Primer of radiologyPrimer of radiology
The endThe end