Presentation1.pptx, radiological imaging of small bowel disease.
Radiological imaging of
the Small Bowel diseases.
Dr/ Abd Allah Nazeer. MD.
Small Intestine, one of the most important organs for the immune defense.
Largest endocrine organs of the body.
Start from the pylorus and ends at the cecum.
1. Duodenum(20 cm), retroperitoneal and
supplied by the celiac artery and SMA.
1. Jejunum(100 to 110 cm). Occupies upper
left of the abdomen , thicker wall and wider
then the ileum, Mesentery has less fat and
forms only 1-2 arcades.
1. Ileum(150 to 160 cm). Occupies the lower right:
Has more fat and forms more arcuates. Contain
Payer,s patches. Ileum and jejunum and supplied
by the SMA.
Congenital Anomalies of the Small Intestine.
Congenital abnormalities involving the small bowels are detected in neonates
only when they are the direct cause of obstruction. Such abnormalities must
be rectified surgically if the patient is to survive. Clinical signs and symptoms
including abdominal distention, vomiting, and obstipation prompt the
clinician to consult the radiologist, who must determine the presence,
location, and cause of an obstruction.
In a healthy neonate, air can usually be identified in the stomach within
minutes of birth, and within 3 hours the entire small bowel usually contains
gas. After 8–9 hours, healthy neonates demonstrate sigmoid gas. The
diagnosis of obstruction is based on some interruption in this dispersion of air.
Delayed passage of gas through the neonatal gut may occur as a result of
traumatic delivery, septicemia, hypoglycemia, or brain damage. Absence of
gas in the bowel may be noted in neonates with severe respiratory distress
who are undergoing mechanical ventilation and in cases of continuous
nasogastric suction .
Radiography is the most valuable means of determining whether obstruction
is present. This modality is often diagnostic; even if it is not, however, it may
help determine the next most useful diagnostic procedure
Congenital anomalies causing incomplete obstruction ( e. g,
stenosis, webs, duplications, malrotations, peritoneal bands,
aganglionosis) may not manifest until later in life, and other
types of examinations (e. g, barium enema studies,
ultrasonography [US], computed tomography [CT], magnetic
resonance [MR] imaging) are generally needed for diagnosis.
In this article, we discuss the importance of pediatric
radiation protection and various means of ensuring adequate
protection. We also discuss and illustrate a variety of
congenital anomalies affecting the small bowel. evaluate the
efficacy of various imaging modalities in the diagnosis and
management of these conditions; and discuss the
embryologic and pathologic basis of radiologic findings in
appropriate cases as well as differential diagnoses and
Jejunal atresia. (a) Supine radiograph in a neonate with associated
esophageal atresia shows three dilated loops of bowel. st = stomach.
Ileal atresia. (a) Upright radiograph shows multiple air-fluid levels
occupying the entire abdominal cavity. (b) Image from a barium
enema study shows numerous dilated, air-filled loops of bowel and
a small, unused colon (functional microcolon).
Non-rotation. Images from a contrast material-enhanced gastrointestinal examination
show the small intestine on the right side of the abdomen and the colon and cecum on
the left side. The ileum is seen crossing the midline from right to left (arrows in b).
Midgut volvulus. Image from a contrast-enhanced upper gastrointestinal
series clearly demonstrates the “corkscrew” appearance of the proximal
small bowel (arrows) as it twists around the superior mesenteric artery
Malrotation. Abdominal CT scan shows the superior mesenteric vein (+)
lying anterior to the superior mesenteric artery. The superior mesenteric
vein normally lies on the right side of the superior mesenteric artery; in
malrotation, it lies either in front or on the left side
Ileal duplication. (a) Image from a barium enema study shows extrinsic
compression of the cecum by an extraluminal mass. (b) US image shows a cystic
mass (C) that corresponds to a surgically proved duplication cyst. k = kidney.
Tumors of the Small Bowel.
Tumors of the small bowel are rare. They are usually single,
but may be multiple particularly in certain syndromes (i.e.
intestinal polyposis syndrome). Tumors can be benign or
malignant. Some benign tumors can progress and become
malignant (i.e. adenomas, leiomyomas). Most small intestine
tumors are clinically silent for long periods; nearly half of all
benign small intestine tumors are found only incidentally
either during an operation or an investigation to visualize the
intestine for other reasons. Symptoms can be chronic and/or
intermittent and include abdominal pain, nausea, weight loss
and bleeding. The larger the tumor, the more likely the patient
will experience symptoms of bowel obstruction. Tumors can
also become ulcerated and bleed.
Benign Tumors :Leiomyoma – Leiomyomas are tumors of one of the
muscle layers of the bowel wall. Some can grow into the lumen of the
bowel and become ulcerated and cause bleeding or anemia, which is the
most common symptom and finding. They can be very difficult to diagnose,
especially when they occur in the small intestine. Endoscopic ultrasound is
a useful way to determine the site of the tumor within the bowel wall.
Some leiomyomas do have malignant potential. Biopsy sampling and
surgical resection are usually advised.
Adenomas – Adenomas are benign tumors that do have malignant
potential. They cause symptoms due to blockage. When they arise in the
region of the papilla or the area of the duodenum where the bile duct and
pancreas drain they can cause jaundice. Because of the risk of malignant
degeneration, adenomas are usually removed (by surgery or endoscopy).
Lipomas – Lipomas are collections of fatty tissue within the wall of the
intestine. They are characterized by a soft yellowish appearance when
viewed endoscopically. These are completely benign tumors with no
malignant potential. Lipomas do not need to be removed unless they
become very large and cause obstructive symptoms (or bleeding due to
Hemangiomas – Hemangiomas are collections of blood vessels that
form a benign vascular tumor in the wall of the stomach or intestine.
They are benign and sometimes found in conjunction with other
syndromes (i.e. Turners syndrome, Tuberous sclerosis, blue-rubber-bleb
syndrome and Osler-Weber-Rendu syndrome). Hemangiomas can cause
gastrointestinal bleeding and anemia. They are detected by endoscopy.
They can be treated endoscopically with application of a heater probe to
burn the vessels. Patients may need resection of areas of intestine
heavily involved with hemangiomas if they cause significant bleeding.
Various medicinal therapies (i.e. estrogens) have been tried to reduce the
amount of bleeding from hemangiomas. Reports of success have been
Neurogenic Tumors – Neurogenic tumors are benign growths arising
from neural (nerve) tissue. The most common variety is neurofibroma.
They are usually solitary. When multiple and found diffusely in the
intestine they are more likely to be associated with neurofibromatosis.
The diagnosis can be confirmed by their microscopic appearance after
Malignant Tumors : Adenocarcinoma of the small intestine probably
develops mainly from adenomas. Most tumors occur at the ampulla in the
duodenum. Other risk factors for adenocarcinoma include Crohn's disease,
celiac sprue, different types of previous surgery (i.e. surgery joining the
urinary system with the intestines), and neurofibromatosis. Patients can
present with obstruction or bleeding. The tumor may be diagnosed by
radiologic techniques (barium studies), endoscopy or surgery, and
confirmed by biopsy sampling.
Intestinal Lymphoma – Intestinal lymphoma of the small intestine is
a recognized complication of celiac sprue, and can occur in
immunodeficiency syndromes. Symptoms include crampy-like abdominal
pain, weight loss, features of malabsorption, bleeding, or even bowel
Leiomyosarcoma – This is a malignant tumor arising from the muscle wall
of the intestine and can also arise from a benign leiomyoma. Treatment
should involve complete surgical resection, wherever possible.
Chemotherapy and radiation are also used.
Metastatic Malignancy from Other Organs – (i.e. lung, breast or
Carcinoid of the small bowel arise from
enterochromaffin or Kulchitsky cells found in the
base of crypts of lieberkuhn. These cells are also
known as argentaffin cells because of their
staining by silver compounds. While secrete
hormone serotonin and substance P. Carcinoid
tumor occurs throughout the GIT, but particularly
in the appendix, terminal ileum and rectum. The
lesion is hard, white nodules arise from deep
aspect of the mucosa and small in size. They
metastases to regional LN and liver.
Coronal and axial CT showing low density clearly delineated mass in duodenum/jejunum.
Low intensity of the mass on MR T1 fat sat. Macroscopic image of lipoma.