Gastrointestinal Imaging

Question 1

What pathologies are shown on an abdominal x-ray?

Answer 1

1. Obstruction a. Small bowel obstruction b. Large bowel obstruction (and volvulus)
2. Colitis (and toxic megacolon)
3. Pneumoperitoneum
4. Abnormal calcifications

Question 2

Pneumoperitoneum

Answer 2

Pneumoperitoneum is pneumatosis (abnormal presence of air or other gas) in the peritoneal cavity, within the abdominal cavity.

Question 3

How can you tell if the bowel is dilated?

Answer 3

369

• 3cm Small bowel • 6cm Large bowel • 9cm Caecum

Question 4

What condition can be seen here?

What is the sign?

Answer 4

Sigmoid volvulus

Coffee bean sign

Question 5

Sigmoid volvulus

Answer 5

It is a common cause of bowel obstruction and constipation.

Sigmoid appears dilated on X-ray with coffee bean sign.

Question 6

What are the two commonest causes of small bowel obstruction?

Answer 6

Adhesions

Hernia

Question 7

What are adhesions?

Answer 7

Adhesions are areas of scar tissue that can cause organs or tissues in the abdomen to stick together. Usually found in the small intestine where it loops and piles up, adhesions can cause some of these loops to stick together, which can result in abdominal pain and occasionally obstruction (blockages) in the gut.

Question 8

What is the most common cause of large bowel obstruction?

Answer 8

Colorectal carincoma

Question 9

What condition is shown here?

Answer 9

Cecal volvulus

Question 10

Cecal volvulus

Answer 10

Cecal volvulus is a rare form of intestinal obstruction. It occurs when the cecum, which is between the small bowel and colon, detaches from the abdominal wall and twists on itself.

Question 11

What condition is shown here?

Answer 11

Question 12

What is the condition shown here?

• what is the sign and why does it appear?

Answer 12

Chronic colitis

Lead pipe sign - caused by the loss of the haustral folds of the colon.

Question 13

What is the condition shown here?

Answer 13

Toxic megacolon

Question 14

Toxic megacolon

Answer 14

Toxic megacolon (or toxic colitis) is defined as a severe episode of colitis with segmental or total dilatation of the colon.

Question 15

What is the condition shown here?

Answer 15

Pneumoperitoneum

• shown by gas under the diaphragm and the double wall sign.

Question 16

Understand Rigler’s sign:

Answer 16

Question 17

Rigler’s sign is seen in what condition on X-ray?

Answer 17

Pneumoperitoneum

Question 18

Read this on the best strategy when it comes to approaching an X-ray.

Answer 18

1. Who, what, where, when, why?
2. Bowel
3. Lungs
4. Organs
5. Bones
6. Soft tissues

Question 19

What causes Rigler’s sign?

Answer 19

Rigler’s sign is a radiological sign of free intraperitoneal air, generally from a perforated viscus. It is the appearance of air on both sides of the bowel wall due to a large quantity of free air in the abdomen.