Exam 3: CXR

Question 1

What is it called when materials of the same radiographic density meet and there is no distinct border on CXR?

Answer 1

Silhouette sign

Question 2

Which side of the diaphragm is typically higher on CXR?

Answer 2

The right side

Question 3

What makes up the hilum? Which side is usually higher?

Answer 3

Hilum is made up of pulmonary arteries and major bronchi. Left is typically higher than the right .

Question 4

What is the aortic knob?

Answer 4

Represents the left lateral edge of the aorta as it arches backwards over the left main bronchus and pulmonary vessels

Question 5

What CTR (cardio thoracic ratio) is considered abnormal?

Answer 5

Greater than 1:2

Question 6

How do you assess for inspiratory effort on CXR? What is considered good and what is adequate?

Answer 6

• Count the posterior ribs visible above the diaphragm

- 10 or more is excellent, 8-9 is adequate

Question 7

Does an underexposed CXR appear more white or black?

Answer 7

Underexposed appears more white, while overexposed appears more black

Question 8

What CXR findings can be seen with COPD?

Answer 8

Hyperlucency, flattened diaphragms, hyperinflation “barrel chest”

Question 9

What is the primary cause of PTX and who does it typically occur in?

Answer 9

• Primary cause is a bleb

- typically occurs in tall patients in their 20s

Question 10

What is a tension PTX?

Answer 10

Shift of intrathoracic structures, tracheal deviation

Question 11

How is a PTX best diagnosed?

Answer 11

An expiratory CXR, the volume of the PTX remains the same and lung volume shrinks making the PTX more obvious
-CT scan also definitive

Question 12

What is the gold standard in diagnosing pneumomediastinum?

Answer 12

CT

Question 13

What is important to rule out when pneumomediastinum?

Answer 13

Esophageal perforation

Question 14

What is a common complication of pneumo-mediastinum?

Answer 14

Air often dissects up to the neck and produces subcutaneous emphysema

Question 15

What is the most common cause of pneumoperitoneum?

Answer 15

Disruption of the wall of a hollow viscous, mechanical ventilation, and postoperative free intraperitoneal gas

Question 16

What is the difference between a pleural effusion and an infiltrate?

Answer 16

A pleural effusion is fluid in the pleural space, and an infiltrate is fluid in the lungs

Question 17

What are the common CXR findings in CHF?

Answer 17

• interstitial edema (Kerley B lines)
• Air bronchograms
• bilateral hazy, perihilar infiltrates in a butterfly or bat wing pattern

Question 18

What are air bronchograms?

Answer 18

When air filled bronchi pass through fluid.

PNA or in CHF, air bronchograms are not seen in an effusion

Question 19

What is atelectasis?

Answer 19

Collapse or incomplete expansion of pulmonary parenchyma

Question 20

What is the most common etiology of atelectasis?

Answer 20

Bronchial obstruction from neoplasms, mucus plugging, and foreign bod aspiration

Question 21

What should you be suspicious for if you see peripheral, rounded nodules of variable size scattered throughout both lungs on CXR?

Answer 21

Pulmonary malignancy