Small bowel obstruction: the role of computed tomography in its diagnosis and management with reference to other imaging modalities

Small bowel obstruction is a leading cause of acute surgical admissions for abdominal pain. There is an increasing tendency for initial conservative management rather than immediate operative intervention, as a proportion of cases will resolve spontaneously. This has resulted in a growing reliance on radiological investigations to reassure the surgeon that medical therapy can be safely instituted. The onus therefore rests with radiologists to guide their surgical colleagues by correctly interpreting the plain abdominal radiograph and suggesting appropriate further investigation if warranted. Recently, computed tomography (CT) has been proposed as the test of choice to define the level and cause of acute small bowel obstruction and to identify complications such as ischaemia and perforation which will prompt surgical intervention. This review will discuss the utility of early CT in the diagnosis of acute small bowel obstruction and outline its impact on patient management.     

MRI对实验性闭袢性小肠梗阻肠壁缺血评估的价值

目的 探讨MRI多序列扫描对实验性闭袢性小肠梗阻肠壁缺血的诊断价值. 材料与方法 24只大白兔实验性闭袢性小肠梗阻模型分为3组,每组8只:A组(缺血1～1.5 h)、B组(缺血2～2.5 h)和C组(缺血5～6 h),对照肠壁组织病理改变分析MRI表现. 结果 A组、B组和C组测量的肠壁厚度分别是(0.135±0.033) cm、(0.185±0.030) cm、(0.383±0.060) cm,肠壁厚度之间的差异有统计学意义(P＜0.05).A组8只、B组5只闭袢肠壁增强扫描出现持续强化,C组闭袢肠壁均无强化.肠壁无坏死组出现持续强化征象明显高于肠壁坏死组(P＜0.05). 结论 MRI多序列扫描可评价肠壁不同时间的缺血.     

螺旋CT三期扫描对小肠早期缺血的评价

目的　评价螺旋CT三期扫描对小肠早期缺血的诊断价值。方法　 80例健康者 (对照组 )和 45例肠缺血患者 (观察组 )扫描前均口服水。静脉团注造影剂后 ,分别于增强后 3 0s(动脉期 )、60s(静脉期 )、180s(延迟期 )行螺旋CT扫描。并分别测取三期中小肠各段肠壁及系膜的CT值。结果　 80例健康者 (对照组 ) ,在同一期相中 ,小肠肠壁各段CT值差别无统计学意义 (Ρ >0 .0 5 ) ,但在动脉期、静脉期和延迟期之间 ,有统计学意义 (Ρ <0 .0 1)。系膜在各期相间均无统计学意义 (Ρ >0 .0 5 )。而 45例肠缺血患者 (观察组 ) ,统计结果恰与上述相反。结论　正常小肠在同一期相中 ,各段的强化一致 ,在不同期相间 ,各段的强化有显著差别 ,系膜的强化在各期相间均无变化。若小肠出现上述相反强化 ,即可提示小肠早期缺血     

ROS1-positive Inflammatory Myofibroblastic Tumor of the Small Bowel Causing Obstruction: A Case Report

Inflammatory Myofibroblastic Tumors (IMTs) are rare fibroblastic/myofibroblastic neoplasms that affect predominately pediatric patients and young adults. Almost half of the patients with IMTs have a chromosomal abnormality in the Anaplastic Lymphoma Kinase 1 gene on chromosome 2p23. Although these tumors occur primarily in the lung, lesions have been reported in a variety of intra-abdominal organs like the liver, spleen, and mesentery. Small bowel IMTs are particularly rare. IMTs generally pursue a benign clinical course, however intra-abdominal and retroperitoneal tumors have typically shown higher local recurrence and even distant metastases. The most common presenting symptoms of an intra-abdominal IMT are abdominal pain and change in bowel habits. Laboratory results are nonspecific and can include anemia and minor elevation of inflammatory markers like C-reactive protein. We report an unusual case of IMT in the small bowel causing the obstruction.     

闭孔疝继发小肠梗阻的MSCT表现

目的 探讨闭孔疝继发小肠梗阻的MSCT表现特征.方法 回顾性分析经手术证实的16例闭孔疝继发小肠梗阻患者的临床及影像学资料.其中男1例,女15例;年龄74 ～ 91岁,平均83.5岁.16例均行腹部平片、MSCT平扫及动态增强扫描,其中9例行胃肠道造影检查.结果 MSCT对全部闭孔疝和继发性小肠梗阻均做出准确诊断,而腹部平片和胃肠道造影均未能做出闭孔疝的诊断.16例闭孔疝位于右侧11例(68.8％),左侧5例(31.3％).疝内容物均为回肠并继发低位小肠梗阻,梗阻程度表现为轻度3例(18.8％),中度7例(43.8％),重度6例(37.5％).疝囊形态表现为类圆形9例(56.3％),泪珠状5例(31.3％),短管状2例(12.5％).疝囊最大径2.00～3.20 cm,平均(2.469±0.352) cm;疝囊体积2.02 ～ 9.77 cm3,平均(4.517 ±2.441) cm3.结论 闭孔疝继发小肠梗阻具有特征性MSCT表现,MSCT曲面重组可充分展现疝囊与继发性小肠梗阻之间的解剖关系,能为治疗计划的制定提供有用的影像学信息.     

Atypical abdominal hernias in the emergency department: acute and non-acute

The objective of this pictorial essay is to review uncommon abdominal hernias, many of which present to the Emergency Department with abdominal pain. These hernias may be congenital, post-traumatic, or iatrogenic in origin. They may present as an acute (surgical) abdomen without localizing signs or symptoms. They may present with an obvious antecedent event such as motor vehicle trauma or simply present as an incidental finding. Multi-detector computed tomography is currently the study of choice to diagnose abdominal hernia and to evaluate the possible complications such as small bowel obstruction and/or strangulation. This modality can delineate a “zone of transition” (abnormally dilated bowel transitioning to normal or decreased bowel caliber) or identify the involved anatomy. It can also suggest compromised blood supply.     

小肠粪便征的MSCT征象分析

目的 分析小肠粪便征(SBFS)的MSCT表现,提高对该征象的认识.方法 搜集27例SBFS患者的临床及影像学资料.所有患者均行全腹MSCT平扫,其中9例同时行MSCT增强扫描,将原始数据传入工作站进行多平面重组(MPR).结合临床治疗及预后,分析SBFS的MSCT表现及临床意义.结果 27例SBFS患者中,18例(66.7％)伴有肠梗阻,9例(33.3％)无肠梗阻.SBFS的主要MSCT表现:含有气泡的混杂密度斑驳影,长条形、卵圆形或不规则形,以不规则形(74.1％)多见,边界清或不清,无包壳结构,大部分单发(70.4％),亦可多发(29.6％),增强后SBFS无强化.结论 SBFS具有特征性的MSCT表现,全腹扫描、MPR及合适的窗宽、窗位有助于该征象的检出,为临床治疗提供重要的参考依据.     

实验性小肠闭袢性肠梗阻肠壁缺血程度与时间相关性的CT分析

目的:建立兔小肠闭袢性肠梗阻模型,通过螺旋CT多期扫描,观察小肠闭袢性肠梗阻肠壁缺血程度与时间的相关性。方法:新西兰大白兔54只,随机分为A、B、C三组。A组9只,结扎长约10~15cm的小肠两端,形成单纯性闭袢;B组30只,除按A组形成单纯性闭袢外,同时结扎闭袢肠段的引流静脉;C组15只,在B组的基础上,同时结扎闭袢肠段的供血动脉。术后在不同的时间点行螺旋CT多期扫描。根据小肠梗阻肠壁缺血程度的CT标准,回顾性分析不同程度肠壁缺血所对应的缺血时间。结果:A组在随机的各时间内均表现为轻度肠缺血,缺血时间(107.11±71.65)min;B组表现为轻度、中度和重度肠缺血,其对应的缺血时间分别为(36.11±9.56)min、(98.77±39.12)min和(250.75±52.00)min;C组在随机的各时间内表现为中度肠缺血和重度肠缺血,其对应的缺血时间分别为(30.50±11.91)min和(150.11±71.62)min。结论:根据小肠梗阻的类型,结合螺旋CT多期扫描,可估计小肠肠壁的缺血程度所对应的缺血时间。缺血程度和缺血时间的确定,可为临床治疗方案的选择提供参考。     

CT findings of phytobezoar associated with small bowel obstruction

The purpose of this study was to evaluate CT findings of phytobezoar associated with small bowel obstruction. We evaluated abdominal CT of 19 patients with phytobezoar. Abdominal CT of 6 patients with small bowel feces was included for the comparison. On CT we analyzed morphological features of phytobezoars such as location, number, size, shape, and the presence or absence of an encapsulating wall. The sites of the phytobezoar were in the jejunum in 12 patients (63%) and the ileum in 7 (37%). The phytobezoars were single in number in 13 patients (68%) and multiple in 6 (32%). The mean short- and long-axis diameters of the phytobezoars measured 3.2 cm (range 2.1–5.2 cm) and 5.2 cm (range 2.2–11.0 cm), respectively. The phytobezoars were ovoid in 9 patients, round in 6, and tubular in 4. On CT, phytobezoars appeared as gas-containing masses in 17 patients (89%) and as a solid mass without gas in the remaining 2 patients (11%). An encapsulating wall was noted in 6 patients (32%). Small bowel feces were much more tubular in shape but did not have encapsulating wall on CT. The CT imaging is useful in making the diagnosis of phytobezoar associated with small bowel obstruction. Electronic Publication     

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。     

Superior mesenteric artery syndrome involving the duodenum and jejunum

Superior mesenteric artery (SMA) syndrome is a rare cause of intestinal obstruction involving the duodenum. Diagnosis is based on clinical suspicion with radiologic confirmation. We report an unusual presentation of the SMA syndrome involving both the duodenum and jejunum initially not recognized on contrast-enhanced CT. This case demonstrates the judicious use of multiple modalities in evaluating for this syndrome.     

小肠不全性梗阻的钡剂造影(附23例分析)

目的　探讨钡剂造影对小肠病变所致梗阻的诊断价值。方法　对 2 3例经手术证实的因小肠病变所致不全性梗阻患者行钡餐及小肠插管注钡造影进行回顾性分析。结果　 2 3例小肠梗阻患者中 ,恶性病变 14例 ,良性病变 9例。结论　对小肠病变所致不全性梗阻 ,钡餐及小肠插管气钡双重造影检查均有重要的诊断价值。     

Small Bowel Volvulus Complicated by Bowel Infarction

Teaching Point: Torsion of a segment of the small bowel and its mesentery, together with closed loop obstruction and absent enhancement of paper-thin small bowel walls, is an alarm sign for small bowel volvulus complicated by acute bowel infarction.