CHEST X-RAY Flashcards
What is the first step in a systematic approach to interpreting a chest radiograph?
Begin with general characteristics such as the age, gender, size, and position of the patient.
What should be examined in the periphery of a chest radiograph?
Bones, soft tissue, and pleura including rib fractures, rib notching, bony metastases, shoulder dislocation, soft tissue masses, and pleural thickening.
What is evaluated in the lung on a chest radiograph?
Infiltrates, pulmonary nodules, and pleural effusions.
What cardiovascular structures form the silhouette of the mediastinum on the right side?
- Ascending aorta
- Right pulmonary artery
- Right atrium
- Right ventricle (RV)
What cardiovascular structures form the silhouette of the mediastinum on the left side?
- Aortic knob
- Left pulmonary artery
- Left atrial (LA) appendage
- Left ventricle (LV)
What is the most anterior cardiac structure on the lateral chest x-ray?
Right ventricle (RV).
How is heart size measured on a chest radiograph?
If the heart size is equal to or greater than twice the size of the hemithorax, it is considered enlarged.
What factors can affect heart size on a chest radiograph?
- Size of the patient
- Degree of inspiration
- Emphysema
- Contractility
- Chest configuration
- Patient positioning
Which items should be reviewed on ICU chest radiographs?
- Placement of the endotracheal tube
- Central lines
- Pulmonary arterial catheter
- Pacing wires
- Defibrillator pads
- Intraaortic balloon pump
- Feeding tubes
- Chest tubes
How can one determine which cardiac chambers are enlarged?
- Ventricular enlargement displaces the lower heart border
- LA enlargement creates a convexity between the left pulmonary artery and LV
- Right atrial enlargement bulges the lower right heart border
What are some common causes of chest pain identifiable on a chest radiograph?
- Aortic dissection
- Pneumonia
- Pneumothorax
- Pulmonary embolism
- Subcutaneous emphysema
- Pericarditis
- Esophageal rupture
- Hiatal hernia
What are the causes of a widened mediastinum?
- Aortic dissection/rupture
- Mediastinal bleeding from trauma or misplaced central venous catheters
- Thoracic lipomatosis
- Tumors such as germ cell tumors, lymphoma, and thymomas
What are common radiographic signs of heart failure?
- Enlarged cardiac silhouette
- LA enlargement
- Hilar fullness
- Vascular redistribution
- Linear interstitial opacities (Kerley’s lines)
- Bilateral alveolar infiltrates
- Pleural effusions (right greater than left)
What is vascular redistribution and when does it occur in heart failure?
Vascular redistribution occurs when upper-lobe vessels become larger than lower-lobe vessels, typically at pulmonary capillary occlusion pressures of 12 to 19 mm Hg.
How does LV dysfunction lead to pleural effusions?
LV dysfunction causes increased hydrostatic pressures, leading to interstitial edema and pleural effusions.
How helpful is the chest radiograph in identifying and characterizing a pericardial effusion?
The CXR is not sensitive for detection of pericardial effusion and may not help determine extent, but a large cardiac silhouette may suggest it.
What are the characteristic radiographic findings of significant pulmonary hypertension?
- Enlargement of central pulmonary arteries
- Rapid tapering of vessels
- Cardiac enlargement (particularly RV)
- Calcification of pulmonary arteries
What is Westermark’s sign?
An area of oligemia beyond an occluded pulmonary vessel seen in pulmonary embolism.
What is rib notching?
Erosion of the inferior aspects of the ribs seen in patients with coarctation of the aorta.
What does pericardial calcification suggest?
It suggests diseases affecting the pericardium, such as tuberculosis, and is highly indicative of constrictive pericarditis.
What is subcutaneous emphysema?
Accumulation of air in the subcutaneous tissue, often tracking along tissue plains.
What is pneumopericardium?
Air in the pericardial space, which is extremely rare.
What is subcutaneous emphysema?
The finding of subcutaneous emphysema is almost always associated with a serious medical condition or complication.
Subcutaneous emphysema refers to the presence of air in the subcutaneous tissue, often indicating significant underlying issues.
What is pneumopericardium?
Pneumopericardium is air in the pericardial space and is extremely rare.
Causes include blunt trauma, penetrating injury, infectious pericarditis, fistula between the pericardium and adjacent air-containing structure, and iatrogenic complication.
What are the common causes of pneumopericardium?
- Blunt trauma
- Penetrating injury
- Infectious pericarditis with a gas-forming organism
- Fistula between pericardium and adjacent air-containing structure
- Iatrogenic complication
Pneumopericardium can arise from various medical scenarios, including trauma and infections.
What is a pericardial cyst?
A pericardial cyst is a fluid filled structure that can be either congenital or acquired.
Pericardial cysts are usually found incidentally and are most commonly located at the right cardiodiaphragmatic angle.
Where are pericardial cysts most commonly located?
- Right cardiodiaphragmatic angle
- Left cardiodiaphragmatic angle
- More superiorly
The location of the cyst can vary, and they are often detected through imaging techniques.
How is the diagnosis of a pericardial cyst most often confirmed?
Diagnosis is most often confirmed by chest CT.
Imaging techniques like chest X-ray or echocardiography may initially suggest the presence of a cyst.
What does calcification of a pericardial cyst suggest?
Calcification of a cyst suggests a bronchogenic cyst, teratoma, or echinococcal cyst.
The characteristics of the cyst can provide insight into its nature and potential origins.
