Pulmonology Imaging Flashcards
What are the indications for a CXR?
Initial imaging test to assess dyspnea, chronic cough, chest pain, injury
Evaluate for pneumonia, COPD, rib/collarbone fractures, TB, pneumothorax, pleural effusion, interstitial lung dz
What are the benefits for CXR?
Fast, widely available, cheap, usually no side effects
What are the risks for CXR?
Low risk of cancer from excess radiation exposure, avoid in pregnant women due to risk of radiation injury to fetus
What is the most sensitive sign on CXR for hyperinflation of the lungs?
Flattened diaphragm usually due to emphysema (COPD)
What is the imaging of choice for flattened diaphragm?
CXR
Describe a barrel chest
Increase AP diameter of the chest wall
Most commonly associated with COPD
CXR provides adequate imaging with minimal risk
Air fluid level on a CXR indicates presence of what?
Cavitation due to lung abscess (collection of pus within parenchyma)
Commonly caused by infection or by aspiration of oropharyngeal contents
What is the most common risk factor for lung abscess with air fluid level?
Alcoholism
What are the sx for lung abscess with air fluid level?
Fatigue, night sweats, fever, weight loss, productive cough, chest pain, +/- bad breath
What is the modality of choice for lung abscess with air fluid level?
CXR
What is a pleural effusion?
Abnormal accumulation of fluid in the pleural space
What are the sx for pleural effusion?
Dyspnea, pleuritic chest pain, +/- cough
What will be present during the PE for a pt with pleural effusion?
Dullness to percussion and decreased breath sounds
What is the imaging of choice for pleural effusion?
CXR is best initial test, shows blunting of costophrenic angle
What is the pulmonary meniscus sign?
Meniscus found on the surface of fluid commonly seen with pleural effusion on CXR
Due to surface tension b/w two different fluids in pleural cavity (normal serous fluid and pleural effusion)
Accumulates in costophrenic angles on PA CXR and in substernal region on lateral CXR
What are the indications for a ventilation perfusion (VQ) scan?
Primarily used to diagnose or rule out pulmonary embolism
What are the pros for a VQ scan?
Readily available, minimal risk, accurate in detecting blood clots
What are the risks of a VQ scan?
Injection pain, injection site bruise, radioisotope allergy, small amount of radiation exposure, not recommended if pregnancy or breast feeding
What are the sx of a pulmonary embolus?
Suddenly onset dyspnea, pleuritic chest pain, tachypnea, tachycardia, low grade fever, cough
What is the imaging of choice for pulmonary embolism?
Chest CT with contrast in stable pts with suspected PE bc its noninvasive and more available than VQ scan
If a pt has normal CXR with suspected pulmonary embolus what imaging is done?
VQ scan
What is the “gold standard” for PE?
Pulmonary angiography but it is very expensive
What are the pulmonary indications for CT?
Pulmonary nodule screening, lung cancer, bronchiectasis, interstitial lung disease (if CXR raises suspicion)
What are the risks for contrast enhanced CT?
Low risk of cancer from excess radiation exposure, allergic reaction to contrast
What are the contraindications for contrast enhanced CT?
No contrast in pts with renal dz, pregnant women (Can have CT in emergency only)
What are the pros for contrast enhanced CT?
Low dose radiation CT is superior in lung cancer screening bc it is more sensitive then CXR with less radiation exposure vs standard chest CT
Describe a fractured rib
Often seen due to hematoma at site of the fracture
Ribs 4-10 fractures most often
Appears as abrupt discontinuity in the smooth outline of rib +/- lucent fracture line
What is the common pattern for rib evaluation?
Examine posterior portion of rib
Anterior portion
Lateral portion
Flow entire rib if abnormality is spotted
What is the imaging of choice for fractured rib?
May not see on fracture on CXR
CT is more sensitive
CXR is taken after to asses for possible pneumothorax
