螺旋CT平扫对绞窄性肠梗阻的诊断价值

目的:探讨CT平扫在诊断绞窄性肠梗阻的价值。方法:对34例经手术证实的绞窄性肠梗阻的平扫CT资料进行回顾性分析。结果:肠壁增厚水肿、靶征、腹水、肠系膜水肿、漩涡征和鸟嘴征是诊断绞窄性肠梗阻的可靠征象,肠壁增厚失去分层改变、局限性肠壁密度增高、腹水或肠液密度增高及肠壁、门脉积气则高度提示肠壁坏死。结论:CT平扫能快速有效地诊断绞窄性肠梗阻。     

急性肠缺血的CT征象分析

目的:分析急性肠缺血的CT征象,提高CT对急性肠缺血诊断的准确性.材料和方法:2004～2005年间经急诊CT平扫及增强扫描,53例被诊断为急性肠缺血,分析其CT征象并与临床治疗和手术结果相对照.结果:CT平扫及增强图像显示:①肠腔扩张及积液53例次.②肠壁增厚伴密度改变39例次,其中平扫时肠壁内见散在点状高密度影7例次,肠壁密度降低22例次.增强扫描肠壁黏膜层异常强化15例次.③肠系膜血管走行异常并血管增粗(漩涡征)10例.④肠系膜脂肪水肿及渗出(缆绳征)26例.⑤肠系膜动脉钙化斑26例;其中有5例可见肠系膜动脉内等密度无强化的血栓影;另3例经手术证实肠系膜上动脉近肠小血管襻内血栓形成,但CT未能显示.⑥肠系膜静脉血栓形成4例.全部53例病人中,39例内科保守治疗后好转,14例症状未缓解者,经外科手术治疗,证实10例为肠系膜动脉血栓形成(其中3例CT未显示血栓),4例为门静脉血栓形成.结论:肠腔扩张和积液、肠壁增厚、肠系膜血管缆绳征及腹水是急性肠缺血的CT间接征象.CT平扫结合MDCT增强和CTA图像显示肠壁内密度改变、肠系膜血管内血栓形成或血管硬化导致管腔狭窄、漩涡征,即可确诊.     

绞窄性肠梗阻的多层螺旋CT征象分析

目的探讨绞窄性肠梗阻的多层螺旋CT表现及其价值。方法回顾性分析诊断明确的32例绞窄性肠梗阻和85例单纯性肠梗阻患者的多层螺旋CT资料,结合文献筛选了7种绞窄性肠梗阻的CT征象:(1)肠壁强化减弱或无强化;(2)肠壁持续强化;(3)肠壁或门静脉积气;(4)肠壁增厚;(5)肠系膜血管充血;(6)肠系膜水肿/积液;(7)腹腔大量积液。比较上述CT征象在绞窄性肠梗阻与单纯性肠梗阻病例中的分布及诊断效能。结果上述7种CT征象在绞窄性肠梗阻病例中出现概率明显高于单纯性肠梗阻病例(P均<0.05);前3种征象只出现在绞窄性肠梗阻病例中,32例绞窄性肠梗阻患者中同时具备2项以上征象者占90.6%,85例单纯性肠梗阻患者中具备2项以上征象者仅3例,两组差异有明显统计学意义(χ2=88.752,P=0.000)。结论在诊断肠梗阻基础上,出现肠壁强化减弱或无强化、肠壁持续强化、肠壁或门静脉积气等征象之一或至少其他2种以上CT征象可提示为绞窄性。     

老年绞窄性肠梗阻的影像学诊断

目的:分析老年绞窄性肠梗阻的影像学特征,探讨老年绞窄性肠梗阻的影像学诊断.材料和方法:对照分析本院近年来经临床、手术病理证实的16例老年绞窄性肠梗阻患者的X线、CT、DSA的影像资料和病理结果.结果:16例老年绞窄性肠梗阻中,血运性肠梗阻8例,肠粘连3例、肠套叠2例、嵌顿疝2例、阑尾包块1例.16例X线立、卧位摄片,均见腹部肠腔扩张,积气、积液,CT有12例见节段性肠壁增厚、黏膜下水肿呈"靶征",7例见大量腹水.5例行肠系膜动脉CTA多平面重建(MPR)见局部肠系膜动脉分支狭窄变细.2例行DSA见肠系膜上、下动脉纤细、远端分支显示不清.结论:老年性肠梗阻X线见局限性肠壁增厚,CT见肠壁黏膜下水肿呈"靶征"应考虑绞窄性肠梗阻可能,CTA见局部肠系膜动脉分支狭窄变细或闭塞,有助于绞窄性肠梗阻的诊断.     

双源CT双期增强血管成像对急性肠缺血的诊断

目的:探讨双源CT(DSCT)双期增强扫描血管成像对急性肠缺血(acute mesenteric ischemia,AMI)患者的诊断价值。方法:回顾性分析经手术或介入治疗证实的26例AMI患者的DSCT资料。所有患者均行DSCT双期增强扫描即动脉期和门静脉期血管成像。结果:肠系膜上动脉栓塞8例,肠系膜上动脉血栓形成4例,肠系膜上静脉血栓形成14例。CT直接征象为肠系膜血管内低密度充盈缺损,受累血管腔闭塞(17例)或重度狭窄(9例)。间接征象:肠壁增厚(21例),肠管扩张、肠腔内积液积气(18例),肠壁强化程度降低(7例),肠壁积气(5例),肠系膜脂肪水肿及渗出(19例),"缆绳征"14例,腹腔积液12例。结论:DSCT增强扫描及双期血管成像可清楚显示AMI血管阻塞的部位、范围、程度及继发改变,对明确诊断和指导治疗具有较高的应用价值。     

绞窄性肠梗阻肠系膜及其血管改变的CT研究

目的对经CT检查、有肠系膜及其血管（MRV）改变的30例绞窄性肠梗阻（SO）进行分析，探讨CT诊断的临床价值。方法30例SO，均行CT平扫，其中20例行增强扫描，均显示有不同形式的MRV改变。26例经手术、4例经临床证实，包括粘连性肠梗阻9例，肠扭转8例，肠套叠6例，肠系膜血管闭塞性肠梗阻4例，内疝3例。结果所有病例经CT检查可发现11种CT征象，并可分作：（1）直接征象：包括肠系膜血管闭塞2例，肠系膜水肿及其血管增粗并形态异常19例；（2）间接征象：包括肠壁水肿增厚24例，CT强化肠壁异常6例，肠腔大量积液13例，肠袢特殊形态10例，肠壁、肠系膜出血各1例；（3）并发症征象：包括肠壁间积气3例，肠系膜门脉积气1例，肠系膜积气1例，腹水和气腹共11例。结论急腹症CT检查如能显示MRV改变，结合其他CT征象和临床，可以对SO术前作出诊断。同时也能观察到传统x线不能显示的并发症。     

多层螺旋CT在肠系膜缺血诊断中的应用

目的：探讨多层螺旋CT（MSCT）对肠系膜缺血的诊断价值和临床意义。方法：对43例怀疑肠系膜缺血患者行MSCT检查,包括平扫、动脉期和门静脉期扫描,采用容积成像（VR）、多平面重组（MPR）和最大密度投影（MIP）进行动脉和门脉成像,评价并分析异常的MSCT征象。结果：肠系膜上动脉栓塞7例,管腔内血栓影,肠管扩张积气、积液;肠壁无强化,5例肠壁变薄,2例肠壁水肿增厚。肠系膜上静脉血栓形成36例,肠管扩张积气、积液33例;肠壁水肿增厚伴密度改变（面包圈征）25例;肠系膜血管增粗,脂肪渗出（缆绳征）17例;肠系膜血管走行异常（漩涡征）9例;肠系膜静脉管腔内充盈缺损36例,管壁强化（靶征）27例。结论：MSCT扫描与三维重组技术相结合能准确诊断肠系膜缺血并明确其缺血程度、范围,是一种有效的、无创的影像学检查手段。     

绞窄性肠梗阻的多层螺旋CT征象

目的绞窄性肠梗阻为急腹症之一,病死率高,本研究旨在探讨绞窄性肠梗阻的多层螺旋CT表现,提高术前CT诊断正确率。资料与方法经手术证实为绞窄性肠梗阻的43例患者(研究组),同期搜集97例单纯性肠梗阻作为对照组,比较两组的CT征象,分析CT征象诊断绞窄性肠梗阻的敏感度、特异度、阳性预测值和阴性预测值。结果 43例绞窄性肠梗阻中,肠扭转14例,腹内疝8例,闭孔疝4例,股疝17例。研究组CT表现为"鸟嘴征"43例,肠壁气泡4例,肠壁密度增高4例,肠壁强化减弱5例,"X征"8例,扩张肠袢壁增厚11例,肠壁内缘模糊5例,附属系膜血管扩张16例,闭袢16例,"漩涡征"13例,以上CT征象与对照组比较,差异均有统计学意义(P<0.05、P<0.001)。诊断绞窄性肠梗阻敏感度最高的CT征象为"鸟嘴征"(100.0%),特异度最高的CT征象为肠壁气泡、肠壁密度增高、肠壁强化减弱、"X征",均为100.0%。结论 "鸟嘴征"是诊断绞窄性肠梗阻最敏感的CT征象,肠壁气泡、肠壁密度增高、肠壁强化减弱、"X征"为绞窄性肠梗阻最特异的CT征象,扩张肠袢壁增厚、肠壁内缘模糊、附属系膜血管扩张、"漩涡征"、闭袢为绞窄性肠梗阻常见的CT征象。     

螺旋CT检查在绞窄性小肠梗阻诊断中的作用

目的：探讨CT检查在诊断绞窄性肠梗阻中的价值。方法：对CT诊断并经手术证实的32例绞窄性肠梗阻患者的病例资料进行回顾性分析。所有患者均行CT平扫及三期增强扫描。分析内容包括肠系膜血管改变、肠壁强化程度及腹水情况等,并与手术结果进行对比分析。结果：32例绞窄性肠梗阻主要征象有病变段肠管无强化和强化减弱（23/32,72%）,腹腔积液（21/32,66%）,系膜血管改变和网膜浑浊、密度增高（18/32,56%）。结论：肠壁强化程度减退、漩涡征、肠腔积血及腹腔积血是绞窄性肠梗阻比较可靠的征象。螺旋CT检查是诊断有无绞窄性肠梗阻的首选检查方法。     

小肠机械性梗阻的CT诊断

目的 :探讨 CT对小肠机械梗阻的诊断价值。方法 :对 2 1例手术和临床证实的小肠机械性肠梗阻病人的 CT表现进行了分析。全部病人为腹平片和临床检查确诊为小肠机械梗阻病人。男 14例 ,女 7例 ,平均年龄 44 .8岁。结果 :完全性小肠梗阻 13例 ,绞窄性小肠梗阻 5例 ,不完全性小肠梗阻 3例。 1/ 3病例术前 CT显示梗阻病因 ,包括腹腔肿块 ,炎性狭窄。 5例中 4例 (80 % ) CT征象提示肠绞窄存在 ,早于腹平片。肠壁郁血增厚大于 3 mm,肠腔大量积液 ,气液平面中液多于气 ,腹腔广泛性液体渗出伴肠系膜水肿则提示绞窄性肠梗阻。结论 :在明确梗阻病因上 CT较腹平片有明显优势。显示典型绞窄性梗阻征象的敏感性与特异性较腹平片高 ,但无典型征象并不能排除绞窄性肠梗阻存在     

肠旋转不良伴中肠扭转的CT诊断

目的：研究CT对肠旋转不良伴中肠扭转（volvuhus in intestinal malrotation,VIM)的诊断价值。方法：回顾性分析6例手术证实的VDIM的CT表现。男5例,女1例,年龄7～25岁,平均13岁。结果：6例均表现为肠系膜根部类团块影,其中4例见典型“漩涡征”,2例呈类“靶征”,但增强扫描亦出现“漩涡征”。毗邻部肠袢扩张,肠系膜静脉不同程度淤积扩张,2例伴受累系膜、肠壁重度水肿。6例均见系膜根部肠系膜上动脉（superior mesenteric artery,SMA）、肠系膜上静脉（superior mesenteric vein,SMV)血管正常排列迷失。结论：“漩涡征”伴系膜根部SMA、SMV正常排列迷失为本病的特征性CT表现。     

Small bowell volvulus - combined radiological findings]

PURPOSE: We retrospectively evaluated the radiological findings observed at plain abdominal film, abdominal sonography and abdominal CT performed in 66 patients with surgically proven small bowel volvulus. MATERIAL AND METHODS: Sixty-six patients (35 women and 31 men, ranging in age 38-77 years) with surgically proven small bowel volvulus were submitted to plain film, sonography and CT of the abdomen. Abdominal plain film was performed in the upright position (postero-anterior view) in 46 cases, and in the supine position in 20 cases. On plain abdominal film we evaluated the following findings: bowel loops dilatation, air-fluid levels and site of obstruction. At abdominal US, performed with 3.5 e 7.5 MHz probes, we retrospectively searched for: bowel loop dilatation, bowel wall thickening, peristalsis alteration, extraluminal fluid. CT was performed with a helical unit (thickness 4 mm, reconstruction interval 4 mm, pitch 1.5), after intravenous contrast agent (120 ml) infusion (3 ml/s, 55 s acquisition delay from bolus starting) and using a power injector. The following CT findings were searched for: whirl sign, beak sign, extraluminal fluid, bowel loop dilatation, bowel wall thickening, bowel wall or mesenteric alterations. RESULTS: Plain abdominal film showed the following findings: air-fluid levels (92.4% of cases), bowel loops dilatation (71.2%), site of obstruction (42.4%). Abdominal sonography demonstrated bowel loop dilatation (48.5%), extraluminal fluid (48.5%), peristalsis alteration (27.3%), bowel wall thickening (27.3%). The most frequent CT findings were: bowel loop dilatation (95.5%), bowel wall thickening (78.8%), beak sign (69.7%), mesenteric alterations (66.7%), extraluminal fluid (54.5%), whirl sign (13.6%). CONCLUSIONS: Air-fluid levels and bowel loop dilatation were the most frequent radiological findings in our series. Plain abdominal film allowed us to identify signs of obstruction, whereas signs of bowel wall necrosis were accurately shown by abdominal CT.     

CT findings of small bowel strangulation: the importance of contrast enhancement

The purpose of this study is to illustrate computed tomography (CT) findings suggestive of small bowel strangulation. We have performed the precontrast and postcontrast CT with single and multidetector CT scanners and evaluated the bowel wall changes and mesentery changes and correlated them with the operative findings. The direct CT findings suggestive of small bowel strangulation included high-density bowel wall on precontrast scans; lack of, or diminished contrast enhancement of the involved bowel wall; localized mesenteric fluid accumulation (mesenteric congestion); and localized pneumatosis. The indirect CT signs included C- or U-shaped loops with mesenteric vessels converging toward the obstruction site, ascites, target sign, two adjacent collapsed round loops, and whirl sign. We particularly emphasize the importance of contrast enhancement of bowel mucosa for early diagnosis to differentiate strangulation from a mechanical obstruction without bowel ischemia, and also the importance to differentiate proximal secondary gas-filled dilated small bowel loops from distal primary involved fluid-filled small bowel loops because these two types of small bowel loops are present in the single peritoneal cavity. As early recognition of small bowel strangulation may help improve the patient outcome because the involved bowel loops can be preserved without resection, it is essential to become familiar with the CT signs suggested small bowel obstruction strangulation.     

Does the CT whirl sign really predict small bowel volvulus?: Experience in an oncologic population

The objective of this study was to determine the sensitivity of the CT "whirl sign" for the diagnosis of small bowel volvulus in patients who present with a clinical suspicion of intestinal obstruction. Between January 2002 and September 2004, 1,493 CT scans performed in 1,213 patients suspected of having small bowel obstruction were retrospectively reviewed by one attending radiologist with gastrointestinal subspecialization and one senior radiology resident. Multislice helical CT scans were performed after oral and intravenous contrast administration. All CT scans showing a combined vessel and bowel whirl appearance were identified. Other features recorded included the number of degrees of whirl rotation, direction of rotation, presence of bowel obstruction, and signs of ischemia. Diagnoses were determined at either surgery or clinicoradiographic follow-up. Surgical follow-up was available in 174 of the 1,213 patients. There were 460 males and 753 females ranging in age from 1 to 95 years (mean 59 years). A whirl sign was found in 33 of the 1,493 CT scans by reader 1 and in 13 of the 1,493 CT scans by reader 2. In 11 patients, surgery revealed small bowel volvulus (0.9%). Reader 1 detected 7 of the 11 volvuli (sensitivity 64%, specificity 98%, positive predictive value 21%, negative predictive value 99.7%). Reader 2 detected 3 of the 11 volvuli (sensitivity 27%, specificity 99%, positive predictive value 23%, negative predictive value 99.5%). The CT scans of the four remaining patients with volvulus not initially recognized by either reader were re-reviewed and were felt to contain whirl signs. Most patients with small bowel volvulus can be identified on CT through detection of a whirl sign. However, most whirl signs detected on CT will not prove to be indicative of small bowel volvulus.     

Closed loop intestinal obstruction: role of computerized tomography]

PURPOSE: The obstruction of a bowel segment at both ends results in a closed loop obstruction. Progression to strangulation frequently occurs if surgical intervention is delayed. The role of plain radiography in the diagnosis of closed loop obstruction and strangulation has been shown to be limited, while the recent literature has demonstrated the growing role of computed tomography (CT). This paper reports our experience in the study of closed loop obstruction by CT. MATERIAL AND METHODS: The CT studies of 12 patients with surgically confirmed closed loop obstruction were retrospectively reviewed. The following CT signs were used for the diagnosis: a) fluid-filled distended loops, b) C-shaped incarcerated loop, c) radial distribution of several dilated bowel loops and mesenteric vessels converging toward the point of obstruction, d) triangular or fusiform tapering of the closed loop and/or whirl sign in the site of obstruction. RESULTS: On the basis of these signs, the diagnosis was made in 11 of 12 patients. Only 1 patient, who had a negative CT study, was positive at a subsequent enteroclysis. CT findings of strangulation were associated in 3 cases: slight wall thickening with vascular congestion and mesenteric ascites, confirmed at surgery. DISCUSSION AND CONCLUSIONS: Small bowel obstruction can be distinguished into simple and closed loop obstructions. The latter is a more severe condition which is often complicated by strangulation with vascular impairment, edema and intramural and mesenteric hemorrhage. Consequent arterial insufficiency rapidly leads to ischemia, infarction and necrosis. The radiologist plays a role in the early recognition of the closed loop obstruction and of any sign of strangulation. The role of CT in the diagnosis and workup of patients with suspected intestinal occlusion has been analyzed in the literature with reported 63% sensitivity, 78% specificity and 66% accuracy. CT is also capable of revealing the causes of occlusion in 73-95% of cases. The above CT signs, as confirmed in our experience, allow to identify closed loop obstruction and also small bowel strangulation, thus supplying a valuable contribution to diagnosis and accurate preoperative evaluation. We conclude that CT can accurately demonstrate the presence of closed loop obstruction and can be the technique of choice in patients in whom obstruction is associated with clinical signs suggestive of strangulation.     

隐匿性外伤性肠破裂的CT诊断

目的 探讨隐匿性外伤性肠破裂的CT表现,以提高对该病的诊断水平.方法 对11例手术证实的隐匿性外伤性肠破裂CT表现进行回顾性分析.结果 主要特异性CT征象有:(1)游离气体,共4例,位于外伤处小肠周围、膈下、腹膜后间隙,或位于包块内各l例;(2)肠间隙血肿或肌壁间高密度血肿(4例);(3)肠壁损伤征,受累肠肇局部低密度影,增强扫描强化局限性减弱,相邻肠管强化相对增强(3例);(4)外伤处小肠及周围包块(4例),增强扫描该包块有明显环形强化,延迟扫描有进一步强化.其他征象有:(1)腹腔及肠间隙积液(5例),周围脂肪间隙或肠间隙模糊改变(8例);(2)肠梗阻(11例).结论 CT对诊断隐匿性外伤性肠破裂钉重要诊断价值.     

Computerized tomography features of intestinal infarction: 56 surgically treated patients of which 5 with reversible mesenteric ischemia]

PURPOSE: Bowel infarction is a rare and typical condition of the elderly; despite improvements in diagnostic imaging and vascular surgery, bowel infarction remains a major cause of acute abdomen, with mortality rates ranging 70-80%. Diagnosis is often late because clinical signs, laboratory data and radiologic findings are aspecific. We investigated radiographic and particularly CT patterns of intestinal infarction in 56 patients submitted to surgery within 12 hours of admission. We also report the CT findings of 5 of these patients who had reversible mesenteric ischemia. MATERIAL AND METHODS: We retrospectively reviewed 56 cases of bowel infarction. The patients were 29 men and 27 women ranging in age 46-84 years (mean: 63). All the patients were submitted to plain radiography of the abdomen in different projections; emergency CT was carried out with i.v. contrast agent injection. We considered the following CT patterns: dilatation of intestinal loops > 2.5-3 mm, wall thickening > 3-4 mm, intraperitoneal effusion, stuffing of mesenteric vessels with diameter > 3 mm, air-fluid levels. RESULTS: Patients in the 7th decade of life were most frequently affected (38 cases), with an overall mortality rate of 59% (33 deaths). Plain radiography showed distention of bowel loops with air-fluid levels in 91% of cases. CT proved to be an accurate technique with higher sensitivity than radiography in detecting mesenteric edema and hemorrhage (68%), abdominal and pelvic effusion (88%), parietal pneumatosis (9%), wall thickening (29%), intraportal gas (7%), and thrombosis of superior mesenteric artery (3.5%). CT patterns in the 5 patients with reversible intestinal ischemia were wall thickening (80%), peritoneal effusion (80%), meteoric dilatatation (40%), a blurred appearance of mesenteric fat (40%). CONCLUSIONS: Angiography is a valuable imaging and treatment technique permitting the diagnosis of vascular occlusion and the intraarterial infusion of vasodilators, but it can be carried out in emergency in few centers only. This makes conventional radiology, and particularly CT, the only tool providing useful information for early diagnosis and treatment of bowel infarction. CT is more sensitive than radiography and does not exhibit the limitations of angiography--i.e., invasiveness, radiation exposure and complex organization. Therefore CT can presently be considered the method of choice in patients with suspected bowel infarction.     

小儿肠梗阻的腹部X线平片和CT诊断价值分析

目的：分析腹部X线平片和CT对小儿肠梗阻的诊断价值，重点探讨小儿绞窄性肠梗阻的CT表现。材料和方法：收集2002年1月-2004年6月复旦大学附属儿科医院手术证实肠梗阻23例，术前24h均拍摄腹部正侧位X线平片，其中14例行腹部CT扫描。结果：23例肠梗阻术前诊断正确率：腹部X线平片为69．6％（16／23）：CT为100％（14／14）。其中，绞窄性肠梗阻术前诊断正确率：腹部X线平片为38．9％（7／18）；CT为90．9％（10／11）。11例绞窄性肠梗阻的主要CT表现包括：小肠壁增厚9例；CT平扫肠壁密度增高7例和“靶征，，2例；CT增强扫描肠壁强化低于正常者6例，3例延迟扫描强化。肠系膜血管增粗水肿5例，4、肠壁积气4例，腹水6例。结论：CT诊断小儿肠梗阻，特别是显示肠绞窄，较腹部X线平片优越。