Radiology- chest x-ray

Question 1

Projection

Answer 1

Refers to the direction x-rays travel through the body.
Posteroanterior
Anteroposterior.

Question 2

PA

Answer 2

Gold standard
sPosteroanterior (PA) viewis the standard frontal chest projection
X-ray beam traverses the patient from posterior to anterior
Performed standing and in full inspiration with the patient hugging the detector to pull the scapulae laterally
Best general radiographic technique to examine thelungs, bony thoracic cavity,mediastinumandgreat vessels

Question 3

advantages of PA

Answer 3

Technically excellentvisualisationof the mediastinum and lungs, withaccurate assessment of heart size​.

Question 4

disadvantages of PA

Answer 4

Patient must be able to stand erect.

Question 5

AP

Answer 5

Anteroposterior (AP) erect viewis an alternative frontal projection to the PA projection with the beam traversing the patient from anterior to posterior
Can be performed with the patient sitting up on the bed and even performed outside the radiology department using a mobile x-ray unit

Question 6

Advantages of AP

Answer 6

More convenient for intubated and sick patients who will not be able to stand for a PA projection

Question 7

Disadvantages of AP

Answer 7

Mediastinal structures may appear magnified as the heart is further away from the detector, often poorly inspired, more likely to be rotated and to create skin folds, scapulae often cover some of the lungs

Question 8

RIPE

Answer 8

Rotation
inspiration
position
exposure

Question 9

Rotation

Answer 9

Find the medial ends of the clavicles
Find the vertebral spinous processes
The spinous processes should lie half way between the medial ends of the clavicle
ROTATION OF THE PATIENT WILL LEAD TO OFF-SETTING OF THE SPINOUS PROCESSES SO THEY LIENEARER ONE CLAVICLE THAN THE OTHER

Question 10

Rotated to left

Answer 10

heart size exaggerated

Question 11

Rotated to right

Answer 11

true size of the heart underestimated

Question 12

Inspiration

Answer 12

Chest X-rays are conventionally acquired in the inspiratory phase of the respiratory cycle. The radiographer asks the patient to, ‘breathe in and hold your breath!’
The diaphragm should be intersected by the 5th to 7th anterior ribs in the mid-clavicular line
WHILE CHECKING FOR ADEQUATE INSPIRATION YOU MAY NOTICE THAT A PATIENT’S LUNGS ARE HYPEREXPANDED (>7TH ANTERIOR RIB INTERSECTING THE DIAPHRAGM AT THE MID-CLAVICULAR LINE)

Question 13

COPD CXR

Answer 13

More than 7 ribs shown
Barrel chest

Question 14

Position

Answer 14

Entire lung field visible

Question 15

Exposure

Answer 15

Penetration is the degree to which X-rays have passed through the body
(A) Overexposure makes it easy to see behind the heart and the regions of the clavicles and thoracic spine, but the pulmonary vessels peripherally are impossible to see.
(B) Underexposure accentuates the pulmonary vascularity, but you cannot see behind the heart or behind the hemidiaphragms.
With modern veiwing systems rarely a problem

Question 16

ABCDE

Answer 16

Airway
breathing
circulation
diaphragm
everything else

Question 17

Airway

Answer 17

trachea, carina, bronchi and hilar structures.

Question 18

Breathing

Answer 18

lungs and pleura.

Question 19

Cardiac

Answer 19

heart size and borders.

Question 20

Diaphragm

Answer 20

including assessment of costophrenic angles.

Question 21

Everything else

Answer 21

mediastinal contours, bones, soft tissues, tubes, valves, pacemakers and review areas.

Question 22

Trachea

Answer 22

Inspect the trachea for evidence ofdeviation:
The trachea is normally located centrally or deviating very slightly to the right.
If the trachea appears significantly deviated, inspect for anything that could be pushing or pulling the trachea. Make sure to inspect for any paratracheal masses and/or lymphadenopathy.

Question 23

true tracheal- pushing of the trachea

Answer 23

large pleural effusion or tension pneumothorax

Question 24

true tracheal- pulling the trachea

Answer 24

consolidation with associated lobar collapse

Question 25

apparent tracheal deviation

Answer 25

rotation of patient

Question 26

Carina and Bronchi

Answer 26

Theright main bronchusis generallywider,shorterandmoreverticalthan theleftmainbronchus. As a result of this difference in size and orientation, it is more common forinhaledforeignobjectsto become lodged in therightmainbronchus.

Question 27

Carina

Answer 27

Thecarinais cartilage situated at the point at which thetracheadividesintotheleftandrightmainbronchus.

Question 28

Hilar structres

Answer 28

Thehilarconsist of themainpulmonaryvasculatureand themajorbronchi.
Each hilar also has a collection oflymphnodeswhicharen’t usually visiblein healthy individuals.
Thelefthilumis often positionedslightlyhigherthan theright, but there is a wide degree of variability between individuals.
Thehilarare usually thesamesize, soasymmetryshould raise suspicion ofpathology.

Question 29

hilar enlagement

Answer 29

bilateral- sarcoidosis
unilateral- underlying malignancies

Question 30

abnormal hilar position

Answer 30

pushed- enlarging soft tissue mass
pulled- lobar collapse

Question 31

Breathing

Answer 31

Inspectthelungsforabnormalities:
When interpreting a chest X-ray you should divide each of the lungs into three zones, each occupying one-third of the height of the lung.
Inspect the lung zones ensuring that lung markings are present throughout.
Increased opacification in a given area of a lung field may indicate pathology (e.g. consolidation/malignant lesion).
The complete absence of lung markings should raise suspicion of a pneumothorax.

Question 32

breathing Plura

Answer 32

Inspectthepleuraforabnormalities:

The pleura are not usually visible in healthy individuals.If the pleura are visible it indicates the presence of pleural thickening which is typically associated with mesothelioma.

Inspect the borders of each lung to ensure lung markings extend all the way to the edges of the lung fields (the absence of lung markings is suggestive of pneumothorax).

Question 33

cardiac- heart size

Answer 33

In a healthy individual, theheartshouldoccupy no more than 50% of the thoracic width(e.g. a cardiothoracic ratio of less than 0.5).

This rule only applies toPAchest X-rays(as AP films exaggerate heart size), so you should not draw any conclusions about heart size from an AP film.

Cardiomegalyis said to be present if theheart occupies more than 50% of the thoracic width on a PA chest X-ray. Cardiomegaly can develop for a wide variety of reasons including valvular heart disease, cardiomyopathy, pulmonary hypertension and pericardial effusion.

Question 34

cardiac- heart borders

Answer 34

Inspect theborders of the heartwhich should be well defined in healthy individuals:
The right atrium makes up most of the right heart border.
The left ventricle makes up most of the left heart border.

Theheart bordersmay becomedifficult to distinguishfrom thelungfieldsas a result of pathology whichincreases the opacity ofoverlying lung tissue:
Reduced definition of the right heart border is typically associated with right middle lobe consolidation.
Reduced definition of the left heart border is typically associated withlingularconsolidation

Question 35

Diaphragm

Answer 35

Theright hemidiaphragmis, in most cases,higher than the leftin healthy individuals (due to the presence of the liver). The stomach underlies the left hemidiaphragm and is best identified by the gastric bubble located within it.

Thediaphragmshould beindistinguishablefrom theunderlyingliverin healthy individuals on an erect chest X-ray, however, iffreegasis present (often as a result of bowel perforation),air accumulates under the diaphragmcausing it toliftand becomevisibly separate from the liver.

Question 36

PNEUMOPERITONEUM

Answer 36

PRESENCE OF AIR OR GAS IN THE ABDOMINAL (PERITONEAL) CAVITY

Question 37

Costophrenic angles

Answer 37

Thecostophrenicanglesare formed from thedome of each hemidiaphragmand thelateralchestwall.

In a healthy individual, the costophrenic angles should beclearly visibleon a normal chest X-ray as a well definedacuteangle.

Loss of this acute angle, sometimes referred to as costophrenic blunting, can indicate the presence offluidorconsolidationin the area.

Question 38

everything else

Answer 38

Bones
Inspect thevisibleskeletalstructureslooking for abnormalities (e.g. fractures, lytic lesions).

Soft tissues
Inspect thesofttissuesfor obvious abnormalities (e.g. large haematoma).

Tubes, valves and pacemakers
Varioustubesandcableswill be visible asradio-opaque lineson the chest X-ray (e.g. central line, NG tubes,ECG cables).

Artificial heart valvestypically appear asring-shaped structureson a chest X-ray within the region of theheart(e.g. aortic valve replacement).

Pacemakerstypically appear as aradio-opaque disc or ovalin theinfraclavicularregionconnected topacemakerwireswhich are positioned within the heart.

Question 39

consolidation

Answer 39

infection