what can you evaluate with xray for a pacemaker
Evaluation of suspected pacemaker lead fracture
Pacemaker placement
the thicker the structure the _____ it will appear on x-ray film
brighter
what are the 3 factors that determine shadow brightness on an x ray
thickness
density
duration of exposure
pneumonic used in assessing xrays
Airways Bones (and soft tissue) Cardiac silhouette (and mediastinum) diaphragm (and gastric bubble) Effusions Fields (ie: lung fields) Lines tubes devices surgeries
what x ray views can you see the vertebral bodies on
Lat is best
PA you can see but not as well
It is normal for the right hemidiaphragm to be slightly _____ than the left
higher
what lung fissures are seen on x ray and what view can you see in it
Horizonal
only on the PA
what view is the lung apex not visible above the clavicle?
Lordotic view
consequence of z-axis rotation
cardiac silhouette, mediastinum and/or hilum may all be distorted
How many posterior ribs can be seen with adequate inspiration and why is that important
10
better quality film
consequences of insufficient inspiration for a chest x ray
Lung volumes appear falsely low
lung markings appear falsely prominent
false appearance of pulmonary edema
cardiac silhouette and mediastinum may appear falsely large
what physical factors determine low exposure vs high exposure. What can the x ray tech do to control these
Duration of exposure - tech controls mAs
Energy of photons - tech controls kVp
Source to image distance - SID
what are you looking for on an x-ray in regards to airway
narrowing
deviation
foreign objects
what radiographic finding is seen in croup and tracheal stenosis
subglottic airway narrowing
what is the hallmark sign in airway narrowing on an xray called
Steeple sign
Tracheal deviation is usually cause by
unequal intrathoracic pressures between R and L sides
abnormalities that cause tracheal deviation away from the affected side
Pneumothorax
Pleural effusion
large mass
abnormalities that cause tracheal deviation towards the affected side
marked atelectasis/collapsed lung
lobectomy/pneumectomy
pleural fibrosis
pulmonary fibrosis (rarely unilateral)
carinal angle >90 degrees
splaying of R and L bronchi
Bone problems seen on x ray
fractured deformed sclerosed lytic osteopenic (difficult to identify on x ray) Notched (applies to ribs only)
scoliosis is visualized in what views
PA and AP
Kyphosis is visual in what views
Lateral only
what radiographic finding is seen in advanced COPD
Kyphosis
increased AP diameter
“Barrel Chest”
increased density in bone
sclerosis
etiologies of Sclerosis
osteoblastic metastasis primary bone tumor various benign tumor like lesions Paget's disease chronic osteomyelitis
decreased density in bone
lytic lesions
etiologies of lytic lesions
osteolytic metastasis multiple myeloma various benign cyst like bone lesions pagets disease acute osteomyelitis
focal deformation of one or more ribs
rib notching
notching of the superior surface (less common) etiologies
osteogenesis imperfecta
connective tissue diseases
local pressure
hyperparathyroidism
notching of the inferior surface etiologies
coarctation of the aorta
subclavian or SVC obstruction
s/p Blalock Taussig shunt (only 2 upper ribs)
anatomic rib varient
cervical rib
unilateral or bilateral
usually incidental finding but can cause thoracic outlet syndrome
subcutaneous emphysema
etiologies from air introduced internally
Pneumothorax
Pneumomediastinum
Pulmonary interstitial emphysema
subcutaneous emphysema etiologies from air introduced externally
penetrating chest wall trauma
post surgical
complications from chest tube
subcutaneous emphysema etiologies from air introduced locally
necrotizing infection with gas producing organisms
gas gangrene
which chest x ray view will exaggerate the size of the heart
AP film
cardiomegaly is said to be present if
the cardiothoracic ratio is greater than 50% on the PA film
cardiothoracic ration =
maximum horizontal cardiac width divided by
maximum horizontal thoracic width (inner surface of the rib cage)
etiologies of cardiomegaly
any cause of L or R sided heart failure
_____ _______ can be mistaken for cardiomegaly
pericardial effusions
x ray findings for L atrial enlargement
splaying of the carinal angle >90%
Double density sign
etiologies for L atrial enlargement
L sided heart failure (any cause) mitral valve disease -mitral stenosis -mitral regurgitation -mitral valve prolapse
x ray findings that may indicate r ventricular enlargement
filling of the retrosternal space (seen on a lateral view)
etiologies for R ventricular enlargement
Pulmonary hypertension (any cause) Pulmonary valve disease (pulmonary stenosis, regurgitation)
Primary finding for a pericardial effusion is an
enlarged cardiac silhouette (not all are visible on x ray)
other findings
water bottle morphology of silhouette
Oreo cookie sign
oreo cookie sign is seen on what x ray view
lat
what are the layers of the oreo cookie sign
posterior chocolate layer = pericardial fat
middle cream layer = pericardial effusion
anterior chocolate layer = epicardial fat
acute pericardial effusion etiologies
trauma
viral pericarditis
complication of MI (free wall rupture, Dressler syndrome)
Iatrogenic (RV biopsy, EP procedures)
sub acute to chronic pericardial effusion etiologies
Malignancy renal failure collagen vascular disease hypothyroidism tuberculosis
widened mediastinum is defined as >
8 cm on PA
most cases of widened mediastinum are due to suboptimal technique such as
rotated pt
poor inspiratory effort
AP view
what anterior and superior mediastinal masses can be visualized on x ray
lymphoma thyroid thymus teratoma aortic aneurysm (superior only)
what middle mediastinal masses can be visualized on x ray
lymphadenopathy aortic aneurysm pericardial cysts dilated esophagus hiatal hernia
what posterior mediastinal masses can be visualized on x ray
neurogenic tumors
extension of spinal masses (tumors, infection)
anterior mediastinal masses are better seen on what view
lat
Hilar enlargement categories
malignancy infection other which includes - sarcoidosis silicosis pulmonary hypertension pulmonary artery aneurysm bronchogenic cyst
Small pneumothorax is
2 cm
large pneumothorax is >
2 cm
based on the thickness of the rim of air around the lung at the level of the hilum on a PA film
size of a pneumothorax
what type of film shows pneumothorax better
expiratory film
Deep sulcus sign is an indication of a
pneumothorax
etiologies of primary (spontaneous) pneumothorax
develops in the absence of lung disease or iatrogenic procedures
etiologies of secondary pneumothorax
iatrogenic (thoracentesis, lung biopsy, central line placement)
COPD
Cystic fibrosis
pneumonia
which effusions seem to defy gravity? why is this important
Loculated instead of free flowing
difficult to drain
what other view other than PA to assess how free flowing the effusion is
Lat decub view with effusion side down.
fluid accumulation between the lung base and the diaphragm which does not track up the pleura, and does not blunt the costophrenic angle
subpulmonic effusion
fluid collection trapped within a fissure which can give the appearance of a lung mass
pseudotumor
transudative pleural effusion etiologies
heart failure
hepatic hydrothorax (pleural effusion due to cirrhosis/ascites)
hypoalbuminemia
nephrotic syndrome
exudative pleural effusion etiologies
pneumonia/empyema malignancy pleural tuberculosis pancreatitis sarcoidosis various rheumatologic diseases -lupus, rheumatoid arthritis, ect
diffuse pleural thickening is seen in
prior infection prior hemothorax occupational exposure (asbestos) radiation malignancy
elevated hemidiaphragm caused by
diminished lung volume
phrenic nerve paralysis
eventration of the diaphragm
free air under diaphragm
pneumoperitoneum
Perforated viscus from PUD, appendicitis, diverticulitis, malignancy, bowel obstruction, complication of endoscopy
post op complication
trauma
peritoneal dialysis
causes of pneumoperitoneum
trauma esophageal rupture vomiting asthma post neck or chest surgery barotrauma
causes of pneumomediastinum
trauma
bacterial pericarditis secondary to gas producing organism
post cardiac surgery
pericardial drain
fistula between pericardium and either lung, stomach or esophagus
causes of pneumopericardium
gas seen between liver and diaphragm
chilaiditi’s sign
refers to condition of ab pain or other symptoms caused by the interposed colon
chilaiditi’s syndrome
Hyperinflation is seen in
COPD
acute exacerbations in asthma
Kerley A lines represent
channels between peripheral and central lymphatics
Kerley B lines represent
interlobular septa (may have heart failure)
In cardiogenic pulmonary edema the cardiac size is typycally
enlarged
in non-cardiogenic it is typically normal
Regional distribution of opacities in non cardiogenic and cardiogenic pulmonary edema
Cardiogenic - relatively homogenous
non-cardiogenic - opacities are relatively patchy
Air bronchograms are common in what type of pulmonary edema
non-cardiogenic
Peribronchial cuffing is more common in what kind of pulmonary edema
Cardiogenic
Kerley b lines are more common in what kind of Pulmonary edema
Cardiogenic
nodules <= 2mm
miliary tuberculosis fungal infection silicosis coal workers pneumoconiosis sarcoidosis
nodules > 2cm
metastatic cancer subacute hypersensitivity pneumonitis lymphoma sarcoidosis granulomatosis with polyangiitis rheumatoid nodules
relatively large, dense, homogenous opacification, frequently involving an entire lobe
consolidation
loss of the normally visible border of an intrathoracic structure caused by an adjacent pulmonary density
silhouette sign
an abnormal increase in opacification overlying the spine while moving superior to inferior on the lateral view, suggestive of lower lobe opacities/infiltrates
Spine sign
causes of focal opacities
Infections (pneumonia) Malignancy Pulmonary infarction Pulmonary hemorrhage vasculitis Eosinophilic pneumonia
Homogenous consolidation
air bronchograms common
sharp borders corresponding to fissures is consistent for what and caused by what?
Lobar pneumonia
streptococcus pneumoniae
Klebsiella pneumoniae
Haemophilus influenzae
Patchy opacification
Air bronchograms uncommon
vague borders
frequently bilat
what is it
what causes it
segmental pneumonia (Bronchopneumonia)
Staphylococcus Aureus
Pseudomonas aeruginosa
Klebsiella pneumoniae
Haemophilus influenzae
Reticular pattern
no air bronchograms
often develops into airspace disease
Interstitial Pneumonia
Mycoplasma pneumoniae
viral pneumonia
pneumocystis pneumonia
Spherical opacification
Easily mistaken for tumor or other lung mass
Much more common in children than adults
Round Pneumonia
H. Influenzae
streptococcus pneumoniae
Distinguished by cavities
may or may not have air-fluid level
Cavitary Pneumonia
Tuberculosis
Staphylococcus aureus
a well circumscribed, generally round density, smaller than 3 cm in diameter
Solitary Pulmonary nodule
Causes of Solitary pulmonary nodules
Cancer
Infectious/inflammatory
(granuloma, pneumonia)
Congenital anomalies - arteriovenous malformation or bronchogenic cyst
what 3 categories of etiologies cause multiple pulmonary nodules
Cancer
- Pulmonary metastasis
- Lymphoma
Infectious/inflammatory
- Fungal pneumonia
- mycobacteria
- nocardia
- septic emboli
- parasites
- Rheumatoid Arthritis
- Vasculitis
Misc
-Amyloidosis
Hampton’s Hump indicates
pulmonary embolism
cant always be detected on x ray
dome shaped opacity due to lung infarction - takes months to resolve and can leave scarring
Westermark sign
pulmonary embolism
cant always be detected on x ray
focal reduction in appearance in lung markings due to embolis
Fleishner Sign
pulmonary embolism
cant always be detected on x ray
prominent central pulmonary artery caused by distension of the vessel caused by a PE
Typically arise within preexisting lung cavities and get colonized with Aspergillus. Pt asymptomatic, may have a chronic cough
Aspergilloma
“fungus ball”
loss of lung volume due to collapse of lung tissue
Atelectasis
Airway obstruction followed by gas resorption within non ventilated alveoli
Obstructive
Resorptive atelectasis
Tumor
Mucus plug
Foreign body aspiration
External compression of airway
Disruption of normal contact between the visceral and parietal pleura allows the elastic recoil of the lung to pull itself inward
Non Obstructive
Passive (relaxation) Atelectasis
Pleural effusion
Pneumothorax
Space occupying lesion in the thorax physically compresses adjacent lung
Non Obstructive
Compressive Atelectasis
Tumor
Elevated diaphragm
Diminished surfactant results in higher surface tension in fluid lining alveoli with increased tendency for collapse
Non Obstructive
Adhesive Atelectasis
Infant Resp distress syndrome
ARDS
Radiation pneumonitis
Severe parenchymal scarring
Non obstructive
Cicatricial Atelectasis
TB
Idiopathic pulmonary fibrosis
Elevation of the ipsilateral hemidiaphragm
Mediastinal shift
Juxtaphrenic peak sign
Lobar Atelectasis
Etiologies include Lung cancer Foreign body aspiration Mucus plugging External compression of an airway
Density in upper, medial right hemithorax
Superior displacement of R hilum and horizontal fissure
Right upper lobe collapse
A thin shadow overlying the heart on the lateral view
RML collapse
Wedge shaped opacity behind R atrium
RLL collapse
Luftsichel sign
50% of pt will have a portion of the LLL interposed between the collapsed LUL and the aortic arch (Luftsichel sign)
LUL collapse
Triangular opacity behind heart
Inferior displacement of l hilum
Obscuring the outline of the descending aorta
LLL collapse
optimal placement of a central line or PICC places the tip at the
junction of the SVC and R atrium
Optimal placement of a PA catheter (Swan-Ganz) will place the tip at the level of the
hilum, no more than 3 cm r of midline or 1 cm beyond the cardiac silhouette
Proper placement of an Endotracheal tube results in the tip being
approx 5 cm above the carina
Proper placement of NG tube is confirmed by
descends centrally
crosses the diaphragm
once below diaphragm, initially deviates to left
optimally tip should be >10cm below the gastroesophageal junction
Complications seen on X-ray from Cardiac Devices
Pneumothorax
Perforation
Lead fracture
Twiddlers syndrome - lead has been wrapped around device and displaced from person messing with it
in profile
suggests aortic prosthetic heart valve
en face
suggests mitral prosthetic heart valve
What are the 2 big differences when looking at pediatric x rays vs adults
Thymus enlargement - in children younger than 2 this is a normal finding
Double atrium is a normal finding in kids. In adults this would indicate L atrial enlargement
the presence of posterior and lateral rib fractures in infant is highly suspicious for
non accidental trauma
Systematic approach mentioned in ped radiology video
Lung parenchyma Pulmonary vasculature airway/mediastinum Heart Bony abnormalities
meniscus sign points to
pleural effusion
7- shape ribs
pectus excavatum
