Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MODULE 16 - Alimentary Tract Disease > IMAGING - Gastrointestinal Tract > Flashcards

IMAGING - Gastrointestinal Tract Flashcards

1
Q

Identify the different anatomical components of the abdomen on this ventrodorsal radiograph

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Identify the different anatomical components of the abdomen on this lateral radiograph

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the advantages of radiography when imaging the abdomen?

A

Widely available
Good to visualise organ position
Good to visualise changes in organ size/diameter
Good to visualise gas/mineral opacities

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the disadvantages of radiography when imaging the abdomen?

A
  • Any loss of serosal detailing will hinder organ identification and interpretation
  • Several views are required which requires patient sedation or general anaesthetic
  • Not all organs can be visualised
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Which abdominal organs cannot be visualised using radiography?

A

Pancreas
Adrenal glands
Gall bladder

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Which contrast mediums can you use for contrast radiography of the abdomen?

A

Barium based contrast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the advantages of ultrasound when imaging the abdomen?

A

Widely available
Good to visualise free fluid
Good to visualise changes in organ architecture
Good to visualise changes in organ diameter
Real-time imaging
Assessment of motility
Guides fine needle aspirates and biopsies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the disadvantages of ultrasound when imaging the abdomen?

A

Requires experience
Poor modality for bone and gas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the advantages of endoscopy when imaging the abdomen?

A

Endoscopy allows for direct visualisation of the gastrointestinal tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the disadvantages of endoscopy when imaging the abdomen?

A

Endoscopy is limited to visualisation of the stomach, duodenum and colon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe the normal anatomical appearance of the liver on radiography

A

Located in the cranial abdomen
Triangular shape on lateral view
Even soft tissue opacity
Sharp caudal-ventral margin
Falciform fat (fat opacity) ventral to the liver on lateral view

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is indicated when the liver does not have a sharp caudo-ventral margin?

A

Hepatomegaly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the gastric axis?

A

The gastric axis is an imaginary line parallel to the ribs, drawn where the stomach overlaps the liver on a lateral radiograph. The gastric axis can be used to evaluate liver size and the position of the stomach relative to other organs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How does the normal appaerance of the liver on radiographs differn in young patients?

A

Larger liver relative to their body size
Little serosal fat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the key signs of hepatomegaly on a radiograph?

A

Rounding of the caudo-ventral margin
Caudo-medial displacement of the gastric axis
Projection beyond the costal arch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the key signs of microhepatica on a radiograph?

A

Cranial rotation of the gastric axis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

(T/F) Microhepatica can be a normal breed variation

A

TRUE.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are three possible differentials of true microhepatica?

A

Portosystemic shunt
Chronic hepatitis
Diaphragmatic rupture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is a postosystemic shunt?

A

A portosystemic shunt is an abnormal vascular connection that allows blood from the hepatic portal system to bypass the liver and flow into the systemic circulation, allowing metabolic byproducts that are usually removed and detoxified by the liver to accunmulate in the circulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How can a portosystemic shunt cause microhepatica?

A

A portosystemic shunt causes blood from the hepatic portal system to bypass the liver resulting in hepatic atrophy due to decreased blood flow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Describe the normal anatomical appearance of the liver on ultrasound

A

Generally contained within the costal arch
Sharp margins
Architecture consisting of homogenous parenchyma, portal veins and hepatic veins
Can visualise the gallbladder

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the main differentiating feature between portal veins and hepatic veins on ultrasound?

A

Portal veins have hyperechoic walls whereas hepatic veins have hypoechoic walls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Describe the normal anatomical appearance of the gallbladder on ultrasound

A

The gallbladder has a hyperechoic wall with anechoic contents

Note the echogenic sludge within the gallbladder
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are the key signs of hepatomegaly on ultrasound?

A

Rounded margins
Projection beyond the costal arch

Note the liver extendinf beyond the costal arch into the abdomen and displacing the stomach
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the key signs of microhepatica on ultrasound?

A

Liver deep within the costal arch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the key sign of liver hyperechogenicity on ultrasound?

A

Loss of clarity of the portal vessels indicates liver hyperechogenicity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Which differentials can be indicated by a hyperechoic liver on ultrasound?

A

Steroid hepatopathy
Chronic hepatitis
Hepatic lipidosis
Hepatic fibrosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What are two possible causes of steroid hepatopathy?

A

Cushing’s syndrome
Iatrogenic (drug-induced)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is the key sign of liver hypoechogenicity on ultrasound?

A

Increased contrast between the parenchyma and the portal vessels indicates liver hypogenicity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Which differentials can be indicated by a hypoechoic liver on ultrasound?

A

Acute inflammation
Hepatic oedema
Hepatic lymphoma
Hepatic congestion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Identify this hepatic abnormality on ultrasound

A

Hyperechoic, heterogenous hepatic mass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Identify this hepatic abnormality on ultrasound

A

Hyperechoic, heterogenous hepatic mass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What are some of the differentials that can be indicated by a focal hepatic abnormality?

A

Neoplasia
Granulomas
Abscesses
Regenerative hyperplasia
Cysts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is required for definitive diagnosis of a focal hepatic abnormality?

A

Fine needle aspirate (FNA)/biopsy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Which differentials should be considered when you see hepatic vascular abnormalities on ultrasound?

A

Hepatic venous congestion secondary to right sided heart failure
Portosystemic shunt

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Which differentials should be considered when you see biliary abnormalities on ultrasound?

A

Gallbladder sludge
Cholecystitis
Biliary obstruction
Gall bladder mucocoele

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What is the clinical significance of gallbladder sludge in dogs?

A

Gallbladder sludge in dogs is often an incidental finding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What is the clinical significance of gallbladder sludge in cats?

A

Gallbladder sludge in cats is more significant and can indicate cholestasis, cholangitis etc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What is a key sign of cholecystitis on ultrasound?

A

Gall bladder wall oedema/thickening

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What is a gallbladder mucocoele?

A

A gallbladder mucocoele is gallbladder distension with accumulated mucoid secretions which may progress to semi-solid material

Note the striated appearance - this is a severe mucocoele
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

How can you differentiate between a mild and severe gallbladder mucocoele on ultrasound?

A

A mild gallbladder mucocoele is non-distinguishable from sludge however a severe gallbladder mucocoele has a striated appearance

Note the striated appearance - this is a severe mucocoele
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Which dog breed is particularly prone to gallbladder mucocoeles?

A

Border Terrier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

How do you treat a gallbladder mucocoele?

A

Some gallbadder mucocoeles can be treated medically however most gallbladder mucocoeles require surgical removal of the gallbladder as the mucus becomes adhered to the gallbladder wall

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Which differentials can decrease serosal demarcation of the abdominal organs?

A

Decreased serosal fat
Increased soft tissue/fluid opacity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What can cause decreased serosal fat?

A

Young animals
Thin/emaciated patients

46
Q

What can cause increased soft tissue/fluid opacity resulting in decreased serosal detailing?

A

Free fluid
Peritonitis
Carcinomatosis
Severe mesenteric lymphadenopathy
Abdominal masses

47
Q

What are some normal anatomical change seen in obese cats on radiographs?

A

Bunching up of the intestines
Dorsal displacement of the liver due to excess falciform fat

48
Q

Describe the normal anatomical appearance of the stomach on a radiograph

A

The size and content (gas, fluid or ingesta) of the stomach is variable and can even not be visible when empty

49
Q

How is gas distributed within the stomach when the patient is in left lateral recumbency?

A

When the patient is in left lateral recumbency, gas in the stomach distributes to the antrum

50
Q

How is gas distributed within the stomach when the patient is in right lateral recumbency?

A

When the patient is in right lateral recumbency, gas in the stomach distributes to the fundus

51
Q

How can the appearance of the stomach change in dyspnoiec or aerophagic patients?

A

In dyspnoeic or aerophagic patients, the stomach can become gas filled

52
Q

What is required to diagnose a gastric dilatation volvulus (GDV)?

A

To diagnose a gastric dilatation volvulus (GDV), there needs rotation of the antrum and duodenum into the dorsal portion of the abdomen

53
Q

Which three factors should you assess when assessing the gastrointestinal tract on ultrasound?

A

Motility
Layering
Contents

54
Q

How motile should a fasted gastrointestinal tract be?

A

A fasted gastrointestinal tract should have 1 to 2 movements per second

55
Q

What are the different layers of the gastrointestinal tract that can be seen on ultrasound?

A

Serosa
Muscularis
Submucosa
Mucosa
Lumen

56
Q

Which ultrasound view should you use to measure the wall thickness of the gastrointestinal tract?

A

You should measure the wall thickness of the gastrointestinal tract in long axis view

57
Q

How thick should the wall of the canine stomach be on ultrasound?

A

3 - 5 mm

58
Q

How thick should the wall of the feline stomach be on ultrasound?

A

1.1 - 3.6 mm

59
Q

Why is it important to fast patients patients prior to an ultrasound of the stomach?

A

Ideally patients should be fasted prior to an ultrasound of the stomach as ingesta gas will result in acoustic shadowing which will obscure visualisation

60
Q

How long should you fast a patient prior to an ultrasound of the stomach?

A

Fast the patient for 4 hours prior to the ultrasound

61
Q

Describe the normal anatomical appearance of the stomach on ultrasound

A

The stomach will have a cartwheel appearance when empty due to the rugal folds and will often have a small amount of gas which will block the visualisation of part of the stomach wall due to acoustic shadowing. The stomach can vary in size and contents (gas, fluid or ingesta)

62
Q

What can you do to get better visualisation of the stomach on ultrasound when there is gas in the lumen?

Ultrasound of a stomach with gas in the lumen, note you can only see the portion of the stomach wall closest to the probe
A

You can scan the patient standing or give them water to create an acoustic shadow which may improve visualisation

Distended stomach filled with ingesta
63
Q

What are three common gastric lesions that can be seen on ultrasound?

A

Gastric ulcers
Gastric masses
Gastric outflow obstruction

64
Q

What can gastric ulcers progress to?

A

Gastric ulcers can progress to gastric perforation

65
Q

Describe the normal anatomical appearance of the small intestine on a radiograph

A

The small intestine is located in the mid abdomen and the size and content (gas, fluid or both) of the small intestine is variable

66
Q

What is the normal diameter of the small intestine on a radiograph in dogs?

A

1 - 1.5 x height of the L5 vertebral body

67
Q

What is the normal diameter of the small intestine on a radiograph in cats?

A

12mm

68
Q

Which species small intestine can appear bunched up on radiographs?

A

Cats

69
Q

What are the key features of a small intestinal obstruction?

A

Thickening of the small intestinal loops
Foreign body may be visible
Colon may be empty and not visible (if the patient has been obstructed for several days)

Radiograph of a dog with a small intestinal mechanical obstruction (corn on the cob)
70
Q

Which imaging techniques can be useful when investigating a foreign body obstruction of the small intestine?

A

Take several radiograph views
Contrast radiography
Ultrasound
Negative contrast colography

71
Q

What is negative contrast colography/pneumocologram?

A

Negative contrast colography/pneumocologram is a technique used to differentiate between the colon and small intestine when investigating a small intestinal mechanical obstruction, by introducing air into the colon via a rectally inserted urinary catheter to help visualise the colon

72
Q

Identify the key features of this small intestinal obstruction

A
73
Q

What is the key sign of ileus on radiography?

A

General dilation of the small intestine (the whole small intestine will be dilated and there will be no normal small intestinal loops)

74
Q

What are four possible causes of ileus?

A

Gastric dilatation volvulus (GDV)
Peritonitis
Dysautonomia
Mechanical obstruction of the distal gastrointestinal tract

75
Q

What are some of the potential signs of small intestinal neoplasia on radiography?

A

May be masses visible (however these are often obscured by intestinal loops)
May be evidence of mechanical obstruction

76
Q

Which imaging modality should you use to help diagnose small intestinal neoplasia?

A

Ultrasound

If you see signs of small intestinal obstruction in older patients, it is important to consider neoplasia and do an ultrasound

77
Q

What are some key signs of gastrointestinal neoplasia on ultrasound?

A

Mass may be visible
Thickening of the wall layers
Loss of clearly defined wall layers
Irregular lumen
Signs of mechanical obstruction

Note the loss of clearly defined layers, the wall thickening, increased fluid within the lumen (sign of outflow obstruction)
78
Q

What is the gravel sign on radiography?

A

The gravel sign is an accumulation of mineralised material directly above a partial, chronic, gastrointestinal mechanical obstruction

Note the gravel sign, loss of serosal detailing, gassy distention and dorsal displacement of the small intestinal loops

Be aware dogs fed raw food, bones etc can have normal digestion of mineralised material

79
Q

Where should you place the ultrasound probe to assess the duodenum?

A

To assess the duodenum, place the ultrasound probe on the right flank

80
Q

Identify the layers of the duodenum on this long axis ultrasound view

A
81
Q

How thick should the wall of the feline duodenum be on ultrasound?

A

1.3 - 3.8mm

82
Q

How thick should the wall of the canine duodenum be on ultrasound?

A

5.1 - 6mm

83
Q

Where should you place the ultrasound probe to assess the jejunum?

A

To assess the jejunum, place the ultrasound probe on the mid abdomen

84
Q

Identify the layers of the jejunum on this short axis ultrasound view

A
85
Q

How thick should the wall of the canine jejunum be on ultrasound?

A

4.1 - 4.7mm

86
Q

How thick should the wall of the feline jejunum be on ultrasound?

A

1.6 - 3.6mm

87
Q

What is a distinguishing feature of the iluem when assessing the gastrointestinal tract on ultrasound?

A

The ileum has a prominent submucosal layer, differentiating it from the other regions of the gastrointestinal tract

88
Q

What are some of the key signs of gastrointestinal mechanical obstruction on ultrasound?

A
  • Distention proximal to the obstruction
  • Stomach and intestine proximal to the obstruction can be fluid filled indicating outflow obstruction
  • Intestinal walls are generally normal
  • Foreign body may be identifiable
  • Increased or absent gastrointestinal motility
89
Q

How does a solid foreign body typically appear on ultrasound?

A

Often hyperechoic with strong acoustic shadowing, and the gastrointestinal tract will conform to the shape of the foreign body

Ultrasound image of a lolly pop stick obstructing the intestine. Note the intestinal distention, hyperechoic foreign body and the strong acoustic shadowing
90
Q

What is a linear foreign body?

A

A linear foreign body describes long thin objects (such as string etc) which can become anchored under the tongue and swallowed into the gastrointestinal tract where the intestines can become bunched up around the linear foreign body

91
Q

What are the risks of a linear foreign body?

A

Perforation
Peritonitis

92
Q

What are the key signs of a linear foreign body on radiography?

A

Intestines appear bunched up with an undulating outline

93
Q

What are the key signs of a linear foreign body on ultrasound?

A

Intestinal plication
Foreign body material usually appears centrally

94
Q

What is intestinal plication?

A

Intestinal plication refers to the folding of the intestinal wall

95
Q

What is intussusception?

A

Intussusception is the invagaination of a portion of the intestine into the lumen of another

96
Q

What is intussusception associated with?

A

Intussusception is associated with any gastrointestinal disease which causes hypermotility

97
Q

What are the key signs of intussusception on ultrasound?

A

Intussusception has an ‘onion-like’ appearance on ultrasound due to the multiple layers of intestinal wall due to the telescoping of the intestine. Furthermore, there will be regions of mesenteric fat that have been pulled into the intestine

Note the onion like appearance and the hyperechoic mesenteric fat. Also note the foreign body present characterised by the hyperechoic line and strong acoustic shadowing. This caused the intusussception due to increasing motility to remove the foreign body
98
Q

Which signalement is most prone to intussusception?

A

Typically younger animals are prone to intusussception due to hyperperiatalsis due to diarrhoea, however older animals can also present with intusussception

99
Q

What are the key signs of enteritis on ultrasound?

A

Generally there will be no changes
Abnormal content in the lumen
Altered peristalsis
Increased gastrointestinal wall thickness
Increased mucosal echogenicity
Irregular lumenal interface
Wall layering is typically normal
Intestinal corrugation

100
Q

What is intestinal corrugation?

A

Intestinal corrugation refers to the wavy or ridged appearance of the muscularis, the serosa will remain smooth

101
Q

What is typically indicated by intestinal corrugation?

A

Intestinal corrugation typically indicates inflammation however it is quite non-specific

102
Q

Describe the normal anatomical appearance of the large intestine on radiography

A

The large intestine is located in the dorsal abdomen and the size and content (gas, fluid or both) of the large intestine is variable, it may not be visible when empty

103
Q

What is the normal diameter of the large intestine on a radiograph in dogs?

A

Less than 1.5x the length of L7

Radiograph of dilated large intestine
104
Q

What typically prevents full assessment of the colon on ultrasound?

A

Faeces cast an acoustic shadow and typically prevent full assessment of the colon on ultrasound

105
Q

How thick should the wall of the canine colon be on ultrasound?

A

2 - 3mm

106
Q

What can be done to allow for more accurate assessment of the colon?

A

Endoscopy can be done or an enema to remove the faeces from the colon followed by re-scanning with ultrasound

107
Q

How thick should the wall of the feline colon be on ultrasound?

A

1.1 - 2.5mm

108
Q

Which imaging modality is best for assessing the pancreas?

A

Ultrasound

109
Q

What are the anatomical landmarks for the pancreas?

A

The left limb of the pancreas lies between the large curvature of the stomach and the transverse colon, the body of the pancreas lies at the pyloro-duodenal junction and the right limb of the pancreas runs along the duodenum

110
Q

Describe the normal anatomical appearance of the pancreas on ultrasound

A

On ultrasound, the pancreas is hypoechoic and appears similar to fat, making it challenging to visualise. The pancreas should be equal to or smaller than the diameter of the duodenum

Be aware the pancreas is challenging to visualise

111
Q

What are the key signs of acute pancreatitis on ultrasound?

A

Decreased echogenicity of the pancreas (appears more hypoechoic) due to oedema
Pancreas has tiger striped appearance
Surrounding signs of pancreatitis *(hyperechoic hazy looking fat and free fluid)

Tiger striped, oedematous pancreas
112
Q

Which disease can often look similar to pancreatitis?

A

Pancreatic neoplasia

MODULE 16 - Alimentary Tract Disease (23 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions