Pulmonary Opacity: Mixed Opacity & Caveats

Question 1

What is the most common distribution of mixed opacity patterns? What are the most common causes?

Answer 1

focal

• cavitated mass: neoplasia, abscess
• cavitated nodule: metastasis, Paragonimus kellicotti, hematocele
• lobar pattern from lung lobe torsion

Question 2

Focal mixed opacity:

Answer 2

• cavitation within soft tissue mass invades bronchus and necrotic center drains out and is replaced by air
• due to location and distribution, likely primary neoplasia

Question 3

Multifocal mixed opacity:

Answer 3

• multiple cavitated nodules with thicker walls
• Paragonimus kellicotti —> can lead to pneumothorax!

Question 4

Multifocal mixed opacity:

Answer 4

• blood and gas within hematoceles secondary to trauma
• B = bulla
• alveolar pattern with air bronchogram due to pulmonary contusion
• pneumothorax: lungs retracted from body wall

Question 5

What is a vesicular lobar opacity? What is it commonly associated with?

Answer 5

increased soft tissue opacity with small, fragmented gas bubbles throughout (sponge-like appearance)

lung lobe torsion

Question 6

Vesicular opacity, lobar:

Answer 6

• sponge-like appearance of air spaces within soft tissue opacity
• alveolar pattern also seen

Question 7

Why is determining pathology from pulmonary patterns difficult?

Answer 7

most pathology cause mixed patterns —> pick which pattern is the most severe and go with differentials for that pattern

Question 8

What pulmonary patterns are present on a continuum of severity?

Answer 8

unstructured interstitial and alveolar

Question 9

What 2 terms are avoided when describing radiological findings on the lungs?

Answer 9

1. INFILTRATE - histological term, not defined
2. CONSOLIDATION - “merging” of lung lobes, not defined

no differential diagnoses related to these terms!

Question 10

Why are combined terms not used in radiology?

Answer 10

most over-diagnosed respiratory condition - does not aid in determining differentials; should choose the most severe pattern

(bronchointerstitial)

Question 11

True of false:

• There is a cavitated mass present in the left caudal lung lobe.
• There is enlargement of the cardiac silhouette.
• There is border effacement of the left diaphragmatic crus by a mass and focal pleural effusion.
• There is a right cranial lung lobe alveolar pulmonary pattern present.
• There is moderate volume pneumothorax present.
• There is a structured interstitial pulmonary pattern noted throughout all lung lobes.
• There is left sided diaphragmatic rupture.
• There is cranial displacement of the stomach.

Answer 11

• true
• false
• true
• false
• false
• false
• false
• false