Radiology Flashcards
What is the benefit of identifying lung patterns?
Narrow differential list
Name the common lung patterns
Alveolar
Interstitial (Structured v Unstructured)
Bronchial
Vascular
Describe the appearance of an alveolar pattern
Homogenous, uniform opacity that varies from solid and opaque to faint or “wispy”
What radiographic signs often accompany an alveolar pattern?
Lobar sign
Silhouette effect/border effacement
Air bronchogram
What is a lobar sign?
Interface between fluid filled lung and gas filled lung
What is an air bronchogram?
Lucency within the airways surrounded by fluid within the alveoli
Alveolar patterns are considered the ________ pattern
Dominant
What are some differential diagnoses for an alveolar pattern?
Pneumonia - aspiration, bronchopneumonia, hematogenous
Edema - cardiogenic versus non-cardiogenic
Hemorrhage - trauma, coagulopathy
What is atelectasis? How does it appear on radiographs?
Atelectasis = collapse of alveoli
Cardiac shift to collapsed side
You have a patient in-hospital who has developed a cough and elevated respiratory rate. You immediately pull the patient from its kennel and take radiographs. You notice an atelectic lung.
What non-pathologic cause could be contributing to this change?
Atelectasis is common in patients that have been in prolonged recumbency
Allow them to take a few breaths to re-inflate and retake radiograph
Linear interstitial patterns are also called ___________
Unstructured
How does a linear interstitial pattern appear?
Increased hazy, linear opacities
Using vasculature, how can we differentiate an alveolar pattern from an interstitial pattern?
Vasculature is smudged but remains visible in a linear interstitial pattern while you cannot visualize vasculature in an alveolar pattern
How can we artificially create a linear interstitial pattern?
Underexposed radiograph
Expiratory radiograph
What are some causes of a linear interstitial pattern?
Artifact
Geriatric change
Pulmonary edema
Hemorrhage
Pneumonia
Neoplasia
Fibrosis
A nodular interstitial pattern is also called _______
Structured
What characterizes a nodular interstitial pattern?
Relatively circumscribed nodules/masses
Can be singular or multiple of varying sizes
What does a bronchial pattern look like?
End-on thickened bronchi - “donuts”
Longitudinal thickened bronchi - “railroad tracks”
What causes a bronchial pattern?
Thickened bronchial walls
DDX - Bronchitis (chronic), feline asthma, pulmonary parasites
What is a vascular pattern?
Changes in vessel size, shape, or contour
Pulmonary veins are ______ and ______
Ventral and central
What are some causes of a pulmonary vascular pattern?
Heartworm disease - artery > vein
L to R Shunts (Pulmonary overperfusion) - artery and vein enlarged
Venous congestion (L sided HF) - vein > artery
What are important things to analyze when looking at radiographs of a vomiting patient?
Location
Gas patterns
Intraluminal contents
Diameter
How does an increased BCS affect SI location?
SI more centrally located in obese patients
What should a normal SI’s gas pattern look like?
Smooth, homogenous
What is the normal appearance of the colon?
Gassy w/ more ST opaque material
Is it normal for SI to be located more in the right side of the abdomen?
Yes - normal variation
Describe how a linear foreign body might appear on a radiograph
Plication of the bowel
“Commas”
What is the normal canine SI diameter?
<1.6x height of L5 body
SI diameter >____x height of L5 body is suggestive of obstructive disease
2x
What is the normal feline SI diameter?
Less than or equal to 12mm
What is ileus?
Failure of passage of intestinal contents thru bowel lumen
What are the two types of ileus?
Paralytic
Obstructive
How does paralytic ileus appear?
Mild generalized dilation
1 population of bowel
Name some causes of paralytic ileus (there are so many, just try and name a few - basically anything that causes the bowel to not want to contract)
Peritonitis
Post-op abdomen
Enteritis
Pain
Anticholinergic drugs
Sedation/anesthesia
Dysautonomia
GDV and mesenteric volvulus
Electrolyte imbalance
How does pancreatitis result in focal paralytic ileus?
Anatomical relationship between pancreas and duodenum
Inflamed R limb of pancreas can lead to inflammation and hypomotility of the duodenum
Describe obstructive ileus
Dramatic dilation
Portion of bowel cranial to obstruction will be dilated
2 populations of bowel (one dilated, one normal)
Name some causes of obstructive ileus
FB
Intussusception (Puppies!)
Stricture
Neoplasia
Hernia
Adhesions
