Pulmonary Imagine and Diagnostic Procedures Flashcards
What is bronchoscopy used for?
Bronchoscopy
- Indications
- SE
- CI
- allows direct visualization of the trachea, bronchi, and segmental airways out to the 3rd generation of branching.
- can be used to sample and treat lesion or abnormalities such as foreign bodies, bleeding, tumors, or inflammation in those airways
Indications:
- cough
- hemoptysis
- wheeze
- atelectasis
- unresolved pneumonia
- positive cytology
- Abnormal CXR
- Bronchial Obstruction
- Diffuse lung disease
- Pre/post intubation
SE: tachycardia, bronchospasm, or hypoxemia
CI: patients with cardiac problems or sever hypoxemia
What are some of the advantages of flexible bronchoscopy and disadvantages of rigid bronchoscopy?
Advantages of flexible bronchoscopy:
- better control of the airway (can be used for intubation)
- easier to deal with large lesions, foreign bodies
- does not require anesthesia
Disadvantages of rigid bronchoscopy:
-Requires general anesthesia, higher rate of tissue damage/complications.
Complications of bronchoscopy
- injury to teeth
- hemorrhage from the bx site
- hypoxia and cardiac arrest
- laryngeal edema
What are the advantages of Flexible Fiber Optic Bronchoscopy?
- provides magnification and better illumination
- smaller size (permits examination of subsegmental bronchi)
- easy to use in pts with neck or jaw abnormalities
- can be performed under topical anesthesia and useful for bedside examination of critically ill pts.
- suctioning capability helps remove secretion
- can be easily passed through ET tube or in tracheostomy opening
What is Virtual Bronchoscopy?
- computer generated pictures of the endotrachial tree, which are constructed from CT images of the thorax
CXR
-list 4 limitations
Limitations:
- 2D image of 3D structure
- X-ray findings may lag behind other clinical features
- normal x-ray does not rule out pathology
- dependent on good quality image
List the fissures of the left and right lungs
Right:
3 lobes: oblique fissure, horizontal fissure (separates middle from upper lobe)
Left:
2 Lobes : oblique fissure
*Oblique fissure is at T4
Relative Densities
-list from least dense(dark) to most dense(light)
- Gas (Dark)
- Fat
- Water
- Bone
- Metal (light)
What are the three main factors determining the quality of the radiograph?
- inspiration
- penetration…(yes i said it)
- rotation
How should a proper CXR be taken?
- should be taken with full inspiration of air to help assess intrapulmonary abnormalities.
- should see diaphragm at level of 8th-10th rib posteriorly or the 5-6th rib anteriorly.
How might underexposure on CXR affect the radiograph?
How might overexposure affect the radiograph?
-the lungs appear much denser and whiter, may appear as though they have infiltrates.
Overexposure:
-heart becomes more radiolucent and the lungs become much darker, often giving the appearance of lacking lung tissue such as in emphysema.
WHat are the four major positions utilized for producing a CXR?
- Posterior-Anterior (PA)
- Lateral
- Anterior-Posterior (AP)
- Lateral Decubitus
How is a PA CXR taken?
- patient stands upright with the anterior chest placed against the front of the film.
- PA film is viewed as if the patient is standing in front of you with his/her right side on your left.
How is a Lateral Position taken?
-patient stands upright with left side of the chest against the film and the arms raised over the head.
- allows the viewer to see behind the heart and diaphragmatic dome
- typically used in conjunction with PA
How is an Anterior Posterior Position taken?
- when pt is debilitated or immobilized, the film is placed behind the patients back with the patient in supine position
- heart is greater distance from the film it will appear more magnified and the scapulae are usually visible in the lung fields because they are not rotated out of the view.
How is Lateral Decubitus Position taken?
-why would we use this position?
- patient lies on either the right or left side, radiograph is labeled according to the side that is placed down (a left lateral decubitus would have the pts left side down against the film.
- Useful in revealing a pleural effusion that cannot be easily observed in an upright view.
The heart on CXR
- describe its location
- how much of the thorax should it take up?
- what aspects of the heart make sure the left heart border?
- what aspects of the heart make up the right heart border?
Location: 2/3 of the heart should lie on the left side of the chest with the other 1/3 on the right.
- Heart should take up less than half of the thoracic cavity
- The left atrium and left ventricle create the left heart border
- The right heart border is created entirely by the right atrium
What makes up the Hilum?
-major bronchi and the pulmonary veins and arteries
Lungs:
- what to expect on normal CXR
- which fissure can you sometimes see on PA CXR?
- visible markings throughout the lungs d/t the pulmonary arteries and veins, continuing all the way to the chest wall.
- Can sometimes see the horizontal fissure of the right lobe (between middle and upper lobe)
Diaphragm
-which side is higher than the other?
-the right side is usually slightly elevated d/t the liver.
Pleura
-is this visible on CXR?
-no, not unless there is an abnormality such as pleural thickening, or fluid or air in the pleural space.
Silhouette Sign
-what is this?
-if an intrathoracic opacity s in anatomic contact with a border(heart, chest wall, diaphragm), then the opacity will obscure that border.
What is air bronchogram?
What are some common conditions in which you might find one of these?
- a tubular outline of an airway made visible due to the filling of the surrounding alveoli by fluid or inflamm exudates.
- Lung consolidation
- Pulmonary Edema
- Neoplasm
- Normal Expiration
What is consolidation?
-the lung is said to be consolidated when the alveoli and small airways are filled with dense material.
Dense Material may be:
- pus (pneumonia)
- Fluid (pulmonary edema)
- Blood (pulmonary hemorrhage
- Cells (Cancer)
What is Atelectasis?
-complete or partial collapse of a lung or part of the lung.
Typical CXR findings of Pneumonia
- airspace opacity
- lobar consolidation
- interstitial opacities
Pleural Effusion
-what do you expect to see on CXR?
- on an upright film you will see blunting on the lateral costophrenic angles
- on AP film an effusion will appear as a graded haze that is denser at the base
- lateral decubitus film is helpful in confirming an effusion as the fluid will collec on the dependent side.
Pneumothorax:
-what do you see on CXR?
- air without lung markings, in PA film it is usually seen in the APICES since air rises to the least dependent part of the chest.
- air is usually found peripheral to the white line of the visceral pleura
Pulmonary edema
- what are the two type?
- what does this look like?
Types:
-cardiogenic pulmonary edema caused by increased hydrostatic pulmonary capillary pressure
- noncardiogenic pulmonary edema caused by either altered capillary membrane permeability or decreased plasma oncotic pressure.
- looks like diffuse fluid throughout the lungs.
Congestive Heart Failure
-Common features observed on the CXR
Common Features:
- Cardiomegaly
- Cephalization of pulmonary veins
- Appearance of Kerley B lines
- Alveolar edema present in a classic perihilar bat wing pattern of density.
What are Kerly B lines?
-thickened edematous intralobular septa(delicate strands of CT separating pulmonary acini (alveoli bunches)
Emphysema
-what are some common features seen on CXR?
- Hyperinflation with flattening of the diaphragm (and elongated chest)
- Increased retrosternal space
- bullae (bubble like cavity filled with fluid or air)
- enlargment of the RA/RV (cor pulmonale)
Lung Mass
-what does this look like on CXR?
-lesion with sharp margins and a homogenous appearance, in contrast to the diffuse appearance of an infiltrate
Chest CT
-what might be used to enhance vasculature and tissues on some CT scans?
- What parts of the body can be scanned?
- Measurements are called what? Why are these useful?
- IV contrast may be used to enhance vasculature and tissues.
- any part of the body can be scanned.
- measurements called HOUNSFIELD UNITS, used to differentiate cysts, lipomas, hemochromatosis, vascular and avasculare lesion.
What are the types oF CT?
- Standard
- High Resolution
- Low Dose
- CT Angio
What are some indications for Standard CT?
- CXR abnormality
- Pleural and mediastinal abnormalities
- lung cancer staging
- F/U Metastases
- Empyema vs abscess
High Resolution CT
- does this use contrast?
- indications
-no
Indication:
- hemoptysis
- diffusely abnormal CXR
- Normal CXR with abnormal PFTs
- Solitary Pulmonary nodules
- Reversible vs non-reversible lung disease
- Lung bx guid
- assess tx response
Low Dose CT Indications
- screening (smokers/former smokers
- F/U: infections, post lung transplant, metastases
ANgiography (CTA)
- indications
- risks
Indications:
- pulmonary embolism
- aortic aneurysms
- aortic dissection
Risk:
-iodinated contrast: allergy/nephrotoxic
Spiral Chest CT
-indications
- PE, evaluation of flank pain
- detection of kidney stones
- rapid evaluation of trauma
What are some common PATHOLOGIC features on chest CT?
- air bronchograms
- bronchiectasis
- septal thickening
- ground glass opacity
- emphysema
- nodules
- filling defect
Air bronchogram DDX
- pneumonia
- pulmonary edema
- hemorrhage
- brochioloalveolar carcinoma
- lymphoma
Bronchiectasis
- what is this?
- DDX
-This is dilatation of medium sized bronchi leading to impaired clearance…recurrent infection…bronchial damage
- DDX:
- infection
- bronchial obstruction
- CF
- Primary ciliary dyskinesia
- alpha1 Antitrypsin deficiency
- RA
- Sjorgren
- Pulmonary Fibrosis
Common causes of Septal Thickening
- pulmonary edema
- pulmonary hemorrhage
- lymphangitic cancer spread
Ground Glass Opacities in the lungs on CT
- what are these?
- DDX
-decreased air content without totally obliterating the alveoli
DDX:
- Alveolitis or interstitial pneumonitis: Hypersensitivity pneumonitis, Sarcoidosis
- Pulmonary Edema
- Resolving pneumonia/hemorrhage
Emphysema CT
- what will you see?
- DDX
-you will see permanent enlargment of air spaces distal to the terminal bronchioles, destruction of the walls without obvious fibrosis.
-bullous
DDX:
-smoking
-alpha1 antitrypsin deficiency
-IV drugs
-Vasculitis
-CT disorders
Ground Glass Opacities in the lungs on CT
- what are these?
- DDX
-decreased air content without totally obliterating the alveoli
DDX:
- Alveolitis or interstitial pneumonitis: Hypersensitivity pneumonitis, Sarcoidosis
- Pulmonary Edema
- Resolving pneumonia/hemorrhage
Emphysema CT
- what will you see?
- DDX
-you will see permanent enlargment of air spaces distal to the terminal bronchioles, destruction of the walls without obvious fibrosis.
-bullous
DDX:
-smoking
-alpha1 antitrypsin deficiency
-IV drugs
-Vasculitis
-CT disorders
MRI
- advantages
- disadvantages
Advantages:
- no ionizing radiation
- display of vascular anatomy with out contrast
- Visualization of linear structures
- Visualization of hard to see CT areas
- GIves clearer images than CT scan
Disadvantages:
- Claustrophobia
- Noise
- Patient size
- Longer scanning time resulting in motion artifacts
- people with pacemaker cannot have scan
- metallic foreign bodies
Filling defects on CT
-what disease is well defined by hypodensity in the pulmonary artery?
-PE
MRI
- advantages
- disadvantages
Advantages:
- no ionizing radiation
- display of vascular anatomy with out contrast
- Visualization of linear structures
- Visualization of hard to see CT areas
- GIves clearer images than CT scan
Disadvantages:
- Claustrophobia
- Noise
- Patient size
- Longer scanning time resulting in motion artifacts
- people with pacemaker cannot have scan
- metallic foreign bodies
What dye is used in MRI?
-Gadolinium
Indications for MRI
- MS
- Stroke
- Infection of brain/spine/CNS
- Visualizing injuries: torn ligaments
- Evaluating masses in soft tissue, cysts. bone tumors or disc problems
- Specific for Thorax Imagining
- Mediastinal masses
- Malignancies
- TB
- Aortic Dissection
- Cardiac disease
Work up of PE
- CXR
- V/Q scan
- Spiral CT with contrast
- Angiogram***(Gold standard, yet no one does this anymore because there is other less time consuming and invasive events)
What is the triad of characteristics that favor PE?
-what is the presentation of PE?
- Hypercoagulability
- Stasis to flow
- vessel injury
- Presentation:
- dyspnea
- pleuritic chest pain
- low grade fever
- tachycardia
Work up of PE
- CXR
- V/Q scan
- Spiral CT with contrast
- Angiogram***(Gold standard, yet no one does this anymore b ecause there is other less time consuming and invasive events)
True or false, you can dx PE on CXR
-false, most chest x-rays in patients with PE are nonspecific.
What are some hallmark signs of PE on CXR?
- Westermarcks sign: dilation of the pulmonary vessels proximal to the embolism along with collapse of distal vessels, sometimes with a sharp cutoff.
- Hamptoms Hump: a triangular or rounded pleural-based infiltrate or consolidation with the apex toward the hilum
Just look at this card and know this.
- CT angiography of the pulmonary arteries is the usual imaging of choice for PE.
- Pulmonary Angiography is the GOLD standard but invasive.
