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Meckel Meckel DiverticulumDiverticulum
Dr.LamDr.Lam
National hospital of National hospital of PediatricsPediatrics
IntroductionIntroduction
Meckel diverticulum is the most Meckel diverticulum is the most common congenital anomaly of the common congenital anomaly of the gastrointestinal tract, occurring in gastrointestinal tract, occurring in 2%–3% of the population.2%–3% of the population.
Originally described in 1809 by the Originally described in 1809 by the German anatomist, Johann Friedrich German anatomist, Johann Friedrich Meckel (1781–1833).Meckel (1781–1833).
IntroductionIntroduction
The diverticulum is the result of The diverticulum is the result of incomplete atrophy of the incomplete atrophy of the omphalomesenteric duct.omphalomesenteric duct.
Meckel diverticulum occurs with Meckel diverticulum occurs with equal frequency in both sexes.equal frequency in both sexes.
Sixty percent of patients come to Sixty percent of patients come to medical attention before 10 years of medical attention before 10 years of age.age.
IntroductionIntroduction
The most common complications are The most common complications are hemorrhage from peptic ulceration, hemorrhage from peptic ulceration, small intestinal obstruction, and small intestinal obstruction, and diverticulitis.diverticulitis.
Meckel diverticulum are well known, Meckel diverticulum are well known, the diagnosis of Meckel diverticulum the diagnosis of Meckel diverticulum is difficult to establish is difficult to establish preoperatively. preoperatively.
Embryologic FeaturesEmbryologic Features
Embryologic Features Embryologic Features
The omphalomesenteric (vitelline) duct The omphalomesenteric (vitelline) duct is the embryonic communication is the embryonic communication between the yolk sac and the between the yolk sac and the developing midgut.developing midgut.
During the 6th week of embryogenesis, During the 6th week of embryogenesis, the omphalomesenteric duct closes.the omphalomesenteric duct closes.
By the 10th week of embryogenesis, By the 10th week of embryogenesis, the midgut returns to the abdominal the midgut returns to the abdominal cavity and the omphalomesenteric duct cavity and the omphalomesenteric duct becomes a thin fibrous band.becomes a thin fibrous band.
Embryologic FeaturesEmbryologic Features
Incomplete atrophy of the Incomplete atrophy of the omphalomesenteric duct may result in a omphalomesenteric duct may result in a variety of anomalies: variety of anomalies:
1.1. Umbilicoileal fistula (least common ).Umbilicoileal fistula (least common ).
2.2. Omphalomesenteric duct sinus.Omphalomesenteric duct sinus.
3.3. Omphalomesenteric duct cystOmphalomesenteric duct cyst
4.4. Fibrous connection of the ileum to the Fibrous connection of the ileum to the umbilicusumbilicus
5.5. Meckel diverticulum( most common 98%). Meckel diverticulum( most common 98%).
Embryologic FeaturesEmbryologic Features
Umbilicoileal fistula Omphalomesenteric duct sinus
Embryologic FeaturesEmbryologic Features
Omphalomesenteric duct cyst
Fibrous band
Embryologic FeaturesEmbryologic Features
Meckel diverticulum
Histologic FeaturesHistologic Features
Meckel diverticulum is a true Meckel diverticulum is a true diverticulum that is composed of all diverticulum that is composed of all layers of the ileal wall.layers of the ileal wall.
Heterotopic tissue is found in Heterotopic tissue is found in approximately 50% of resected approximately 50% of resected Meckel diverticula.Meckel diverticula.
Histologic FeaturesHistologic Features
Normal small intestinal epithelium lines and Normal small intestinal epithelium lines and focal gastric mucosa in the diverticulum. focal gastric mucosa in the diverticulum.
Histologic FeaturesHistologic Features
Gastric heterotopia is most common, Gastric heterotopia is most common, reported in 23%–50% of cases.reported in 23%–50% of cases.
Histologic FeaturesHistologic Features Heterotopic pancreatic tissue is Heterotopic pancreatic tissue is
found in 5%–16% of cases.found in 5%–16% of cases.
Histologic FeaturesHistologic Features
Meckel diverticulitis Meckel diverticulitis
Clinical FeaturesClinical Features
In the majority of patients, In the majority of patients, Meckel diverticulum is asymptomatic Meckel diverticulum is asymptomatic
25% of Meckel diverticula become 25% of Meckel diverticula become symptomatic ( medical literature )symptomatic ( medical literature )
Many Meckel diverticula are Many Meckel diverticula are discovered incidentally during discovered incidentally during a radiologic evaluation or surgical a radiologic evaluation or surgical procedure performed for other reasons procedure performed for other reasons or they are found at autopsy or they are found at autopsy
Clinical Features Clinical Features
Clinical symptoms arise from Clinical symptoms arise from complications of the diverticulum:complications of the diverticulum:
Peptic ulceration with hemorrhage.Peptic ulceration with hemorrhage. Diverticulitis.Diverticulitis. Intestinal obstruction from Intestinal obstruction from
diverticular inversion, diverticular inversion, intussusceptions, intestinal volvulus.intussusceptions, intestinal volvulus.
Clinical FeaturesClinical Features
Diverticular torsion.Diverticular torsion. Inclusion of the diverticulum in a Inclusion of the diverticulum in a
hernia (Littre hernia).hernia (Littre hernia). Formation of enteroliths.Formation of enteroliths. Development of neoplasia.Development of neoplasia.
Radiologic FeaturesRadiologic Features
Ultrasound sonography.Ultrasound sonography.
Radiologic FeaturesRadiologic Features
Abdominal radiograph.Abdominal radiograph.
Radiologic FeaturesRadiologic Features
Barium examination of the small intestine.Barium examination of the small intestine.
Radiologic FeaturesRadiologic Features
Tc-99m pertechnetate scintigraphy.Tc-99m pertechnetate scintigraphy.
Radiologic FeaturesRadiologic Features
Computer tomography.Computer tomography.
Radiologic FeaturesRadiologic Features
Computer tomography.Computer tomography.
Radiologic FeaturesRadiologic Features
SMA Angiography.SMA Angiography.
PicturesPictures