dxy

A： The normal small-bowel wall is thin, measuring between 1 and 2 mm when the lumen is well distended (Fig. 1). However, the thickness of the normal small-bowel wall varies slightly depending on the degree of luminal distention. As a result, different criteria have been used to diagnose small-bowel wall thickening [1,2,3,4,5,6]. When the lumen of the small bowel is distended, the wall is often not seen. If the bowel is partially collapsed, the wall measures between 2 and 3 mm and is of symmetric thickness. and
this rule same to duodenum.it will be quite beneficial for your diagnosis to inject 654-2 injection before you scan(15 min.).enclosed pictures will show you the case of the Duodenal ampulla carcinoma.

Q：金教授您好
CT检查是诊断急性肠缺血可靠而且比较方便的方法. 随着快速CT、多排探测器CT的应用，扫描时间已可缩短至1 s以下。CTA技术还可将腹腔动脉和静脉显示为与介入法血管造影所见极为近似的冠状面或矢状面图像。与诊断肠缺血的传统方法-介入性血管造影的“标准”方法比较，由于CT检查无创伤性、方法简便和医师无须在射线下作插入导管等操作，已逐渐有代替前者的趋向，目前已成为诊断本病首选的、主要的检查方法。应用CT检查不仅使许多以前被误诊或漏诊的多数急性肠缺血患者能够得到及时正确的诊断，还使多数患者得到极为宝贵的及时手术治疗的机会，大幅度地降低了本病的死亡率。
口服的造影剂应如何选择？怀疑已有急性肠梗塞的患者不用造影剂CT检查效果如何?
谢谢！

A: it is a good question.Bowel ischemia represents a processof insuffcient blood supply of the small or large bowel with the con-sequences ranging from a transient, totally re-versible attack to a lethally catastrophic event.This condition may result directly from arterial occlusion (thromboembolism of the superiormesenteric artery or its branches, vasculitis ofvarious autoimmune diseases, and externalcompression of the artery by adhesion, volvulus, hernia, and intussusception), hypotension(congestive heart failure, hypovolemia, and sepsis), or vasoconstrictive medications (digitalis, norepinephrine, and ergotamine). Bowelischemia may also be associated with impaired venous drainage (thrombosis of the mesentericand portal veins, interference of intramural venous outflow by distention and elevated intraluminal pressure that occurs proximal to a stenotic lesion, and compression of themesenteric veins by tumor, adhesion, volvulus, hernia, and intussusception) .The severity of the ischemic attack depends on the acuteness, duration, degree, and state of the collateral circulation; extent of the involved area; and promptness in correcting the underlying pathologic process. The damage starts with the mucosa, which is mostvulnerable to the ischemic insult, extends outward through the submucosa and the proper muscular layer, and ends at
the serosa. The extent of the injury may range from mucosal, to mural, to transmural necrosis. Oral contrast medium was not routinely used. oral water given recommend-ed.

Q：金教授您好：
我想请教一个问题:
肠管壁增厚的ct技术及诊断与鉴别诊断,与临床内镜超声比较有何差异及优势。

A: good question.it is a key focus to differentiate the dieases.Bowel wall thickening may be related to a number of entities, including normal variants, inflammatory conditions, and neoplastic disease. The CT findings that need to be analyzed when assessing thickened bowel include pattern of attenuation; degree of thickening; symmetric versus asymmetric thickening; focal, segmental, or diffuse involvement; and associated perienteric abnormalities. Evaluation of these parameters, which are reviewed inthe following text, will lead to a more accurate differential diagnosis.
1.Attenuation of the Thickened Bowel Wall (Homogeneous Attenuation,Heterogeneous Stratified Attenuation,Heterogeneous mixed Attenuation.
2.Degree of Bowel Wall Thickening(Mild Thickening,Marked Thickening,
3.Symmetric Versus Asymmetric Thickening
4.Focal, Segmental, or Diffuse Bowel Wall Thickening and Location
5.Associated Abnormalities (Lymph Nodes,Mesenteric Stranding and Calcification,Abscess, Sinus Tracts, and Fistulas,Fibrofatty Proliferation).and I think it is obvious that CT scan is superior to that modality(endoscopy).}

Q： 金教授您好：对于我们临床医生来说“肠管壁增厚的ct技术及诊断与鉴别诊断"还是一个较陌生的技术，我是一个外科和肿瘤科医生，想知道该技术在临床方面主要实用于哪些疾病，特别是外科和肿瘤疾病方面。
非常感谢您光临丁香园指导。

A: CT is used to examine patients with acute abdominal complaints, known or suspected malignancy, abdominal and pelvic trauma, and inflammatory conditions. When CT images of the abdomen and pelvis are interpreted, the focus is often placed on the peritoneal cavity, the mesentery, and the parenchymal organs. A common misconception is that CT provides only limited information with respect to the gastrointestinal tract. In fact, recent technologic advances and accumulated experience in image interpretation suggest that substantial information regarding gastrointestinal tract disorders can be obtained. Normal variants—as well as abnormal conditions—may cause thickening of the bowel wall.includes submucosal hemorrhage or hematoma ,infarcted bowel ,neoplasm ,chronic Crohn's disease ,radiation injury ,and pseudothickening related to incomplete distention and residual fluid etc.

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