1. Introduction to basic of chest x-ray.PDF

I have thoroughly explained chest X-rays in a series of 12 video lectures. This PDF contains the first lecture. I hope you find it beneficial. If you need the other PDF lectures, feel free to reach out to me on Instagram at Nerdosis Medical Lecture.

1. Nerdosis medical lecture 1

2. Indication for chest X-ray
1.Respiratory Symptoms
2.Infection and Inflammation
3.Cardiac Evaluation
4.Screening and Preoperative
Evaluation
5.Chest Trauma
6.Chronic Medical Conditions
7.Foreign Body Aspiration
8.Monitoring of Medical
Treatment
9.Follow-up and Surveillance.
10.Occupational Exposure
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3. How X-ray work?
•To carry of a simple plain X-ray, following should be presents:
1.Source of radiation (machine)
2.X-ray film (detector)
3.A patient to be examined
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4. How X-ray work?
1. Source of radiation
2. Detector (film)
3. patient
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5. How X-ray work?
•The X-ray machine contains an X-ray tube, which is the source of the
radiation. This tube generates X-ray photons, which are high-energy,
ionizing electromagnetic waves.
1. Source of radiation:
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6. How X-ray work?
•The patient is positioned between the X-ray tube and a detector.
•Before the X-ray, the patient is typically asked to remove any metallic objects, such as jewelry,
that could interfere with the image, with their chest exposed.
•They usually stand with their arms extended and hands placed on their hips or on support
structures, like the X-ray table, to maintain a consistent position.
2. Patient:
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7. How X-ray work?
•twomethodsareexist:
1.DigitalDetector:digitaldetectors,oftenpartofasystemcalleddigitalradiography(DR),areusedforchestX-
rays,thesedetectorsconsistofascintillatorlayerthatconvertsX-rayphotonsintolight,.Thisdigitalsignalis
thenprocessedandconvertedintoanimagethatcanbeviewedonacomputerscreen,andthissystemis
fasterandmoreefficientthantraditionalfilm-basedX-rays,andtheimagesareavailableimmediatelyfor
review.(usedinemergency…etc.)
2.TraditionalX-rayFilm:Inthepast,X-rayimageswerecapturedonradiographicfilm.Thisinvolvedatwo-step
processwheretheX-rayimagewasexposedontothefilm,andthenthefilmwasdevelopedtoproducethe
finalimage(beforesurgery,followup…etc.)
3. Detector (film):
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8. How X-ray work?
3. Detector (film):
Digital detector
Traditional
X-ray film
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9. How X-ray work?
3. Detector (film):
Inthefigurepresented(ontheleft)
inthischestX-rayimage,we
observevariationsinshading,with
certainareasappearingdark(black)
andothersappearinglight(white).
Whatistheexplanationforthis
differenceinappearance?
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10. Factor affecting X-ray shadow brightness
•Whenx-raybeamemittedfromthemachinetowardpatientanddetector,AstheX-rayspassthroughthebody,
theyinteractwiththetissues.
•DifferenttissuesabsorbX-raystovaryingdegrees.DensetissueslikebonesabsorbmoreX-rays,whilesofttissues
likemusclesandorgansabsorbfewer.ThedegreeofabsorptioniswhatcreatestheX-rayimage.
•Generallyspeakingthere3factorsthataffectingshadowbrightness:
1.TissueDensity
2.StructureThickness
3.ExposureDuration
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11. Factor affecting X-ray shadow brightness
1. Tissue density:-
•If we places an empty glass jar with metallic cap on a table and
the jar is filled with just air, which is a low-density substance and
on other side x-ray photographic film.
•When wedirect x-rays at the jar and the film.
•As the x-rays pass through the jar, will be passed and hit the
photographic film and turned to black
•While when it hits the cap of the jar which is metal, the x-ray
beam cannot pass to the photographic film that is why it remain
aswhite
•You see the jar appear has hezygray while the cap of the jar
appear white
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12. Factor affecting X-ray shadow brightness
1. Tissue density:-
Another example:
•If we places an glass jar with metallic cap on a table and the jar
is filled with fluid, which is a medium density substance and on
other side x-ray photographic film.
•When wedirect x-rays at the jar and the film.
•As the x-ray directed toward the jar which contain fluid, some of
them can pass through fluid and other will be absorbed, that is
why turnedto grey
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13. Factor affecting X-ray shadow brightness
1. Tissue density:-
What we have talked about in previous slides, the similar is correct if we compare it to human body tissue
•Our body have different types of tissue, and they have different density
•Whenx-raybeamemittedfromthemachinetowardpatientanddetector,AstheX-rayspassthroughthe
body,theyinteractwiththetissues.
•DifferenttissuesabsorbX-raystovaryingdegrees.DensetissueslikebonesabsorbmoreX-rays,whilesoft
tissueslikemusclesandorgansabsorbfewer.ThedegreeofabsorptioniswhatcreatestheX-rayimage.
✓AreaswheremoreX-raysareabsorbed(likebones)appearwhiteintheX-rayimage.
✓WhileareaswherefewerX-raysareabsorbed(likesofttissues)appeardarker.
▪Radiolucent: means dark on X-ray images (e.g., air-filled spaces like the lungs).
▪Radiopaque: means bright on X-ray images (e.g., bones and metal objects)Nerdosis medical lecture 13

14. Factor affecting X-ray shadow brightness
2. Structure Thickness
•Thickerstructures will block more X-rays, resulting in a brighter appearance on the X-ray film.
•Thinnerstructures will block fewer X-rays, leading to a darker appearance on the X-ray film
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15. Factor affecting X-ray shadow brightness
3. duration of exposure
•the duration of exposure affects the image's brightness.
•the duration of exposure, is an important factor in chest X-rays. It
determines how long the X-ray machine emits radiation to create the
image.
✓A shorter exposure results in a brighter image because fewer X-
rays have time to pass through the patient and reach the
detector, making the image appear lighter.
✓Alonger exposure allows more X-rays to pass through the
patient, resulting in a darker image.
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16. Videoanimation
Click below (video)
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17. Factor affecting X-ray shadow brightness
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18. Chest X-ray projection
❑Mian chest X-ray view are:
1.PA (posteroanterior)
2.AP (anteroposterior)
3.Lateral view
4.Lateral decubitus
❑Additional projections:
1.expiration view
2.lordotic view
3.right anterior oblique (RAO)/left anterior oblique (LAO) view
4.ribs AP view
5.ribs PA view
6.sternum lateral view
7.sternum oblique view
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19. Chest X-ray projection
1. PA view:
•theposteroanterior (PA) viewis the standard frontal chest projection
•the x-ray beam traverses the patient from posterior to anterior
•it is performed standing and in full inspiration with the patient hugging the detector to pull the
scapulae laterally
•it is the best general radiographic technique to examine thelungs, bony thoracic
cavity,mediastinumandgreat vessels
•advantages: technically excellent visualization of the mediastinum and lungs, with accurate
assessment of heart size
•disadvantages: patient must be able to stand erect
Note:
it serves as the most sensitive plain radiograph for the detection
of free intraperitoneal gas orpneumoperitoneum in patients
with acute abdominal pain.
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20. Chest X-ray projection
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21. Chest X-ray projection
1. PA view: how to perform PA view
❑Steps of preparation for PA view:
There are three main step for preparation of patient:
1.Positioning
2.Center ray
3.Technical factor
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22. Chest X-ray projection
1. PA view: how to perform PA view
1.Explain procedure
2.Patient should remove following over the chest:
a)jewelry
b)Long hair
c)bras
d)clothes
e)Etc.
3.Tell the patient to face toward the detector
4.The detector should be 5 cm above the level of shoulder
5.the chin (ەگانەچ) is raised as to be out of the image field
6.Rotate shoulder forward to wing our scapula either by:
a)hands placed on the posterior aspect of the hips,elbows partially flexed rolling anterior or
b)hands are placed around the image detector in a hugging motion with a focus on the lateral
movement of the scapulae
7.shoulders are depressed to move the clavicles below the lung apices
8.It is preferred to wear shield to protect gonads from radiation
9.The tube is 6 feet away from patient
1. Positioning
5 cm above shoulder
Centering point= T7
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23. Chest X-ray projection
1. PA view: how to perform PA view
Pelvic shield Bra strap
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24. Chest X-ray projection
1. PA view: how to perform PA view
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25. Chest X-ray projection
1. PA view: how to perform PA view
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26. Chest X-ray projection
1. PA view: how to perform PA view
2. Center ray
1.Centering point:
•the level of the7
th
thoracic vertebra, approximately the inferior angle of the scapulae
2.Collimation
•superiorly 5 cm above the shoulder joint to allow proper visualization of the upper airways
•inferior to the inferior border of the 12
th
rib
•lateral to the level of theacromioclavicular joints
3.Orientation
•portraitorlandscape
4.SID:
•180 cm
5.Respiration:
•Tell the patient to hold breathe during inspiration
•It is preferred to make exposure after 2
nd
full inspiration
Nerdosis
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27. Chest X-ray projection
1. PA view: how to perform PA view
3. Technical factor
❑Exposure
1.Kilovoltage: 110-125 KV
•High kV cause low contrast (figure A)
✓High kV usually require grid
•Low KV high contrast (figure B)
2.Exposure time and milliampere = 4-8 mAs
•mA = milliampere
•S = second
✓High mA→short exposure, which decrease chance of motion artifact
A B
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28. Chest X-ray projection
2. AP view:
•theanteroposterior(AP)erectviewisanalternativefrontalprojectiontothePA
projectionwiththebeamtraversingthepatientfromanteriortoposterior
•itcanbeperformedwiththepatientsittinguponthebedandevenperformedoutside
theradiologydepartmentusingaportablex-rayunit
•advantages:moreconvenientforintubatedandsickpatientswhowillnotbeableto
standforaPAprojection
•disadvantages:mediastinalstructuresmayappearmagnifiedastheheartisfurther
awayfromthedetector,oftenpoorlyinspired,morelikelytoberotatedandtocreate
skinfolds,scapulaeoftencoversomeofthelungs
•aAPsupineviewisafurtheralternativefrontalprojectiontechniqueoftenusedin
traumapatients,orpatientswhocan'tsitup
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29. Chest X-ray projection
2. AP view:
1.Patient is either supine or erect position
2.Facing towards the X-ray tube
3.Detector is placed under patients back
4.Chin is raised as to be out of the image filed
5.if possible, the hands are placed by the patient's side
6.Centering point: the level of the7th thoracic vertebra, approximately 7 cm below the jugular notch of the sternum
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30. Chest X-ray projection
2. AP view:
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31. Chest X-ray projection
2. AP view:
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32. Chest X-ray projection
3. lateral view:
•thelateral viewof the chest is performed erect left lateral and labeled with the side
closest to the cassette
•Main indication for lateral view:
1.Assessment of pleural effusion
2.Localizing foreign body
3.Localizing abnormality after PA view show abnormality over the lung tissue
4.Deformity
5.etc
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33. Chest X-ray projection
4. Lateral decubitus:
•The lateral decubitus view of chest is a specialized projection that is now rarely used due to the ubiquity of CT,
it is chiefly used in the pediatric population
•Mian indication for lateral view
1.Small pleural effusion
2.pneumothorax
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34. Chest X-ray projection
4. Lateral decubitus:
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35. Chest X-ray projection
Next topic : chest x-ray anatomy
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