腸梗阻的ct診斷策略

1、腸梗阻的CT診斷策略—如何透過征象看清本質(zhì)？,福建醫(yī)科大學(xué)附屬第一醫(yī)院影像科鄭賢應(yīng),目 的,書寫報告不夠規(guī)范描述不夠全面診斷不夠深刻無法提供準確的資訊,,何謂腸梗阻 ？,由不同原因引起的一組臨床癥候群，特點是腸內(nèi)容物不能順利通過腸道，從而引起一系列病理生理變化和臨床癥狀嚴重者常致腸管壞死，甚至死亡,,準確的診斷刻不容緩 ！,動力性: 麻痹性、痙攣性,機械性: 腸壁病變、腸管受壓、

2、 腸腔堵塞,血運性： 腸系膜血管栓塞或 血栓形成,病因分類,,,,,診斷思路 之所在！,診斷的 關(guān)鍵！,單純性：無血液循環(huán)障礙,缺血性（絞榨性）：血液 循環(huán)障礙,血液循環(huán)是否障礙,,,影像醫(yī)師的任務(wù),判斷梗阻的部位及范圍判斷梗阻的特性 判斷腸管是否缺血或壞疽,,Diagnosis of SBO,,移行帶,遠端腸管萎陷,,尋找移行帶是診斷的首

3、要任務(wù)！,近端腸管擴張 外徑>2.5cm,判斷腸管是否異常的標準,Caliber of small bowel: 外徑>2.5cmBowel wall thickness：厚度 >3mmAbnormal Enhancement ：superior or inferior to the adjacent bowel wall 強化異常,,這是我們診斷 的重要依據(jù)！,機械性腸梗阻,粘連性腸梗阻Ad

4、hesive SBO,最常見！,但診斷不易！,,,WW 300 WL 0-10 易于顯示粘連帶,粘連帶是診斷的主要依據(jù)！,,移行段和粘連帶,,“Feces sign”提示移行段就在附近！,,,,,“Fat notch sign” 提示梗阻點所在,“Fat notch sign”是粘連性腸梗阻的一個重要征象,鋇劑造影檢查可以清楚地顯示移行帶位置,常規(guī)檢查未能顯示移行帶,腸套疊,成人的腸套疊一般都有其誘因！,Submucosal lipom

5、a associated with small bowel intussusception,,,,粘膜下脂肪瘤,,看到腸系膜及其血管是診斷的關(guān)鍵！,A 54-year-old male complained of abdominal pain for 2 months,GIST,,,,Small bowel intussusception,Small bowel intussusception,腸系膜及血管 是診斷的關(guān)鍵！,

6、腹 內(nèi) 疝,常需急診手術(shù)，診斷須及時！,Foramen of Winslow hernia in a 43-year-old male with acute epigastric pain of 10 hours duration.,,Paracolic internal hernia,Strangulating SBO,3個月前,,Congested mesenteric vessels,,Strangulating SBO due

7、 to internal hernia,腸系膜積液,,,,,男，71歲，腹脹、腹痛3天,診斷要點,局限性腸管擴張腸系膜模糊腸系膜血管擴張,,腸道異物Foreign bodies,,,,1年前,女，76歲，上腹痛3天,,,,,不同的窗寬窗位對異物的顯示效果,diospyrobezoar柿石,A 16-year-old female presented with abdominal pain and distention for

8、5 days,diospyrobezoar柿石,,,Bezoar胃石,Feces sign,,與Feces sign表現(xiàn)不同,腸道異物診斷要點,必須調(diào)整合適的窗寬及窗位清楚的境界，可見假包膜呈橢圓形，混雜的密度,,閉絆性腸梗阻Closed-loop SBO,臨床需要采取更主動的處理措施！,Closed-loop obstruction is unique form of mechanical bowel obstruction

9、 in which two points of intestine along its course are obstructed at single site. C = closed loop, P = proximal loop, D = distal loop.,閉袢型腸梗阻 ？,一段腸袢兩端均受壓，如腸扭轉(zhuǎn)結(jié)腸梗阻時回盲瓣關(guān)閉防止逆流，也可以形成閉袢型腸梗阻容易發(fā)生腸壞死和穿孔影像科醫(yī)師需要準確做出診斷,

10、,a,,,,,,b,,“渦旋征”和“喙征”是腸扭轉(zhuǎn)的典型征象,Whirl sign,Beak sign,另一種“喙征”,Beak sign,“U”型腸絆,“C”型腸絆,相對對稱的腸管擴張和狹窄段,絞榨性腸梗阻Strangulating SBO,需要馬上做出準確的診斷及手術(shù)處理,Strangulating SBO,A mechanical obstruction associated with bowel ischemia，most

11、 often associated with closed-loop SBO 機械性腸梗阻+腸管缺血,,Acute bowel ischemia 急性腸缺血,Characteristic findings,Bowel wall thickness: 腸壁厚度Bowel wall attenuation: 腸壁密度Dilatation of the bowel lumen：腸管擴張Mesenter

12、ic vessels：腸系膜血管Mesentery: mesenteric fat stranding and ascites 腸系膜浸潤或積液,,Indications of ischemia,Circumferential bowel-wall thickening腸壁環(huán)形增厚Bowel wall edema 腸壁水腫Increased attenuation of the bowel wall 腸壁密度增高Subjecti

13、ve decreased relative enhancement of the bowel wall 腸壁強化減弱Mesenteric vascular engorgement 腸系膜血管充血,,Indications of ischemia,Presence of mesenteric fluid 腸系膜積液Presence of ascites 腹水Presence of intramural air, extraalime

14、ntary air, portal venous or mesenteric venous air 氣體,,Indications of infarct,Circumferential bowel-wall thickening: >3mmDiminished or absent bowel wall enhancement 強化減弱或不強化Mesenteric vascular engorgement 腸系膜血管充血Inf

15、iltration of the involved mesentery 腸系膜浸潤Free fluid 游離液體Presence of intramural air, extraalimentary air, portal venous or mesenteric venous air 氣體,,Muscularis propria,submucosa,mucosa,“靶征”,Systemic lupus erythematosus

16、with mesenteric ischemia in a 20-year-old man. Target sign, mesenteric vascular engorgement and haziness are showed on CE-CT scan.,血管炎,Peritonitis associated with bowel gangrene,,,,,Spoke wheel sign輪輻征,Small bowel volv

17、ulus,Congested mesenteric veins,Strangulating SBO due to internal hernia,血運性腸梗阻,急診時經(jīng)常被漏診或誤診！,Superior mesenteric vein thrombosis,腸系膜上動脈血栓形成,,,,,男，40歲，腹痛并肛門停止排氣排便4天,,,男，58歲，左上腹疼痛1周并血便1天,,,A 27-year-old male presented wit

18、h abdominal pain of 10 hours duration,Target sign,,,,,血運性腸梗阻,更多地表現(xiàn)為血管分布區(qū)的腸管管壁增厚，密度增高，腸腔擴張不明顯血管腔內(nèi)的密度改變，是診斷的關(guān)鍵,,總 結(jié),尋找梗阻點是診斷的關(guān)鍵薄層重建是診斷的必要條件判斷腸道是否缺血是診斷的首要任務(wù)CT對腸梗阻能夠進行定位與定性診斷,,你做到了嗎？,診斷原則,確定是否存在腸梗阻尋找梗阻點（定位）判斷梗阻類型（單