腹内疝CT表现专题知识.pptx

Case Old woman with chronic,episodic abdominal pain 腹内疝CT表现专题知识第1页CT images腹内疝CT表现专题知识第2页CT images腹内疝CT表现专题知识第3页Which findings are present?Venous thrombosis?Mesenteric twisting?Displaced bowel loops?腹内疝CT表现专题知识第4页Which findings are present?Within the left upper abdomen,there is thin sac filled with small bowel with swirling vessels identified within it.腹内疝CT表现专题知识第5页Which choice is the most likely diagnosis?A,Paraduodenal herniaB,Foramen of Winslow herniaC,Transmesenteric herniaD,Trans omental herniaE,Congenital malrotation腹内疝CT表现专题知识第6页Paraduodenal Hernia 腹内疝CT表现专题知识第7页Whats paraduodenal hernia the most common type of internal hernia(53%)congenital hernia,hernia sacasymptomatic,colicky epigastric or periumbilical pain M:F=3:1 has left and right two subtypes,the former accounts for about 3/4腹内疝CT表现专题知识第8页 How paraduodenal hernia hapened Left paraduodenal hernia occur when bowel prolapses through Landzerts fossa,an aperture present in approximately 2%of the population.Landzerts fossa is located behind the ascending or fourth part of the duodenum and is formed by the lifting up of a peritoneal fold by the inferior mesenteric vein and ascending left colic artery as they run along the lateral side of the fossa.腹内疝CT表现专题知识第9页 How paraduodenal hernia hapened Right subtype occur when bowel prolapses through Waldeyer s fossa below to the ascending duodenum,and to the right side of the mesocolon.腹内疝CT表现专题知识第10页CT Diagnosis(Left paraduodenal hernia)Axial CT scans demonstrate bowel whin the bowel loops interposed between the stomach and pancreas,some mass effect on the posterior stomach wall,thickened bowel wall,and engorged mesenteric vessels.腹内疝CT表现专题知识第11页CT Diagnosis(Left paraduodenal hernia)axial contrast-enhanced CT scan in 11-year-old boy shows small-bowel loops(arrow)between stomach and pancreas腹内疝CT表现专题知识第12页CT Diagnosis(Left paraduodenal hernia)axial contrast-enhanced CT scan in 28-year-old man shows small-bowel loops(white arrow)behind pancreas(P)(black arrow indicates stomach)腹内疝CT表现专题知识第13页CT Diagnosis(Left paraduodenal hernia)axial contrast-enhanced CT scan in 36-year-old man shows small-bowel loops(arrow)displaying inferior mensteric vein(arrowhead)to left.腹内疝CT表现专题知识第14页CT Diagnosis(Left paraduodenal hernia)coronal construction of contrast-enhanced CT in 28-year-old man shows small-bowel loops between transverse colon(T)and left adrenal gland(arrow)腹内疝CT表现专题知识第15页CT Diagnosis(Left paraduodenal hernia)CT scan of the midabdomen shows the inferior mesenteric vein(arrowhead),this vessel is a landmark for the inferior mesocolon.which is located at the anteromedial border of the encapsulated jejunal loops(J).Diagram(coronal view)of the surgical findings shows that the fossa Landzert is 4cm in diameter(arrowhead)腹内疝CT表现专题知识第16页CT Diagnosis(Left paraduodenal hernia)Mesenteric vessel abnormalities,including enlargement,stretching,and anterior displacement of the main mesenteric trunks,especially the inferior mesenteric vein,to the left,also are helpful findings 腹内疝CT表现专题知识第17页CT Diagnosis(Left paraduodenal hernia)contrast-enhanced CT scan of the upper abdomen shows a saclike mass of dilated jejunal loops(J)between the pancreatic head and stomach.the dilated inferior mesenteric vein(arrowhead)is located at the anterior border of the encapsulated loops.Crowed and engorged mesenteric vessels(arrow)at the fossa of Landzert(L).腹内疝CT表现专题知识第18页 Unlike hernias at other sites,the diagnosis of an internal hernia is more difficult because the site of defect in the mesentery is not obvious on imaging.This is because both the hernial orifice(occupied by the mesentery of the herniated loops)and the surrounding areas are predominantly fat attenuating.Recognition of mesenteric vascular abnormalities is crucial in the diagnosis of internal hernia.腹内疝CT表现专题知识第19页腹内疝CT表现专题知识第20页