Computed tomography of complicated Meckel’s diverticulum in adults: a pictorial review
Alexandra Platon
Pascal Gervaz
Christoph D. Becker
Philippe Morel
Pierre-Alexandre Poletti
Objective To show various CT aspects of complicated Meckel's diverticulum in adult patients to facilitate the preoperative diagnosis of this rare pathology in emergency settings. Methods A computer search of medical records over a 15 year period identified 23 adult patients who underwent surgery for acute abdomen generated by a complicated Meckel's diverticulum. CT images available for review were analyzed, and some specific patterns leading to the diagnosis of complicated Meckel's diverticulum are presented in this review. Results Complications were related to inflammation (14 patients), bleeding (5 patients), intestinal obstruction (3 patients), and penetrating foreign body (1 patient). The presence of a Meckel's diverticulum was usually suggested at CT scan by an abnormal outpouching, blind-ending digestive structure connected to the terminal ileum by a neck of variable caliber. Depending on the type of complications, the diverticulum was surrounded by mesenteric inflammatory changes, or presented as a localized fluid or air-fluid collection contiguous with the terminal ileum. The diverticulum was also the source of active bleeding or acted as the lead point to intestinal obstruction or intussusception. Conclusion CT findings of complicated Meckel's diverticulum are polymorphic and should be considered in the evaluation of adult patients with acute abdomen.
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Meckels diverticulum is a congenital anomaly of the
gastrointestinal system due to incomplete obliteration of
the omphalomesenteric duct. Meckels diverticulum is
found with an incidence of 12% in the general population,
and most of the diverticula remain asymptomatic [1].
Complications result most commonly from bleeding,
inflammation, and obstruction [1, 2]. A study performed
over a 42 year period in a general population showed a
lifetime risk of complications of 6.4% [3]; symptomatic
Meckels diverticulum has been reported in 16% of patients
with surgically proven diverticula [4]. According to this
latter study, younger (<4 years) patients tend to present with
obstructions, whereas adult patients tend to present with
hemorrhage. Complicated Meckels diverticulum usually
manifests during the first years of life, and it is considered
to be a rare pathology in adult life.
The purpose of our review is to show various CT aspects of
complicated Meckels diverticulum in adult patients
encountered over a 15 year period in our emergency department. We
aim to facilitate the diagnosis of complicated Meckels
diverticulum prior to surgery in emergency conditions.
Anatomy and embryology of the Meckels diverticulum
The presence of the Meckels diverticulum is explained by
the intrauterine evolution of the bowel. The initial
embryological communication between the midgut and the yolk
sac is made through the omphalomesenteric (vitelline) duct.
During normal developmental evolution, this duct is
obliterated and disappears; this process usually takes place
during the 8th to 9th week of embryonic life. Different
forms of congenital anomalies will result as a consequence
of failure of closure and/or resorption of this embryological
communication. The pattern of these anomalies depends on
the degree of persistent ductal patency linking the ileum to
the umbilicus; they may appear as fibrous cord, as
ileoumbilical fistula, or as omphalomesenteric cysts [2, 5].
However, the most frequent of all closure anomalies of
the omphalomesenteric duct is Meckels diverticulum,
which received its name in 1809, in honor of the German
anatomist Johann Friedrich Meckel. Meckels diverticulum
development is related to the persistent patency of the
intestinal attachment of the omphalomesenteric duct, while
its umbilical end obliterates. The result will be a true
diverticulum, formed by all the layers of the intestinal wall;
the diverticulum takes its origin from the antimesenteric
border of the small bowel, within 40100 cm of the
ileocecal valve [2, 5]. The arterial supply comes from the
vitelline artery, which is a branch of the superior mesenteric
artery. The diverticulum is normally lined by intestinal
mucosa, but a frequent histological finding is the presence
of heterotopic gastric or pancreatic mucosa [2].
The majority of Meckels diverticulum cases remain
clinically silent during the entire lifetime, and their presence
may be discovered incidentally during surgery, autopsy, or
when performing upper gastrointestinal studies [2, 5].
Bleeding is a frequent complication of Meckels
diverticulum. It is reported to be more frequent in children and young
adults and is usually associated with ulcerations produced by
the acid secretion from the heterotopic gastric mucosa inside
the diverticulum. The bleeding may present as acute massive
hemorrhage or as anemia from chronic bleeding; stools can be
melenic or have a currant jelly-like aspect [2, 5].
Another frequent complication associated with Meckels
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