1. Diagnostic Imaging
Normal chest Anatomy on XR

2. Technique:
Learn the difference between PA vs. AP CXR
Learn the utility of a lateral (decubitus) CXR
Understand the terms inspiration, penetration, and rotation as they apply to determining a technically adequate film
II.  Anatomy:
Learn the basic anatomy of the fissures of the lungs, heart borders, bronchi, and vasculature that can be seen on a chest x-ray

3. III.  Interpretation:
Develop a consistent and thorough technique for reading images
Learn how the silhouette sign can help localize pathology
IV.  Pathology:
Learn the concept of atelectasis and the ability to recognize it on a chest x-ray
Appreciate the appearance of pulmonary edema and the differences between cardiogenic and noncardiogenic causes
Appreciate the difference findings of atelectasis and pneumonia
Recognize pleural effusions and pneumothorax appear on CXR
Recognize the signs of COPD
Recognize the signs of a benign pulmonary nodule
Learn what makes lung cancer unresectable

4. The plain CXR is the most commonly performed imaging exam because:
Cardio-pulmonary disease is common
The exam is quick, easy to do, cheap, with low radiation exposure (a PA CXR gives only about 3-days-worth of radiation exposure we get anyway from natural sources)
Most importantly the contrast elements involved allow us to see the common pathologies we’re looking for
It’s all about the contrast: For any imaging exam to be useful, there must be contrast (signal difference) between lesion and surrounding tissue
There are 4 tissues that have densities that can be distinguished from each other (have contrast) on plain X-ray:
Calcium (bone)
Soft tissue and fluid (not distinguishable on plain X-rays)
Fat
Gas/air
The natural contrast agent of air in the lungs allows us to see the common soft tissue/fluid pathologies (pneumonia, lung CA, pleural effusion, Kerley lines, etc.)

5. Indications for chest X ray:
Chest pain
Investigation of repeated and persistent chest infection
Chest trauma
Localization of biopsy
Evidence of a tumor and metastatic lesion
Inhalation of foreign body

6. Standard views Additional views
There are several projections of chest radiography:
Standard views
Additional views

7. VIEWS: STANDARD VIEWS INDICATIONS: Erect PA LATERAL
For fit and able bodied persons
To diagnose any pathology
To visualize pleural effusion
To localize opacity

8. Posterioranterior and Lateral
The standard chest examination consists of a PA (posterioranterior) and lateral chest x-ray.
The films are read together.  The PA exam is viewed as if the patient is standing in front of you with their right side on your left.  The patient is facing towards the left on the lateral view.  Comparison films can be invaluable - Old Gold!  If you have comparison films, the old PA film is displayed adjacent to the new PA film and the old lateral is displayed adjacent to the new lateral.
On the left is a simulated patient in position for a standard PA (posterioranterior) chest x-ray.  On the right is a normal PA film.

9. PA VIEW AP VIEW normal magnified DIFFERENCE FROM PA:
Magnification of heart occur.
Scapula overlies on lungs
Clavicles above apex

10. CENTERAL RAY: At the level of T6
1)A simulated patient in position
for a lateral chest x-ray
2)a normal lateral film. Note that the receptor or
film is against the left chest.
The lateral view is obtained with the left chest against the cassette. This diminishes the effect of magnification on the heart. Looking carefully at the posterior aspect of the chest on the lateral view, which ribs are left and right? Which is the right/left hemidiaphragm?

11. The right ribs (red arrows below) are larger due to magnification
and usually projected posterior to the left ribs if the patient
was examined in a true lateral position.
This can be very helpful if there is a unilateral pleural
effusion seen only on the lateral view.  

12. The left hemidiaphragm is usually lower than the right. 
Also, since the heart lies predominantly on the left hemidiaphragm the result on a lateral film is silouhetting out of the anterior portion of the hemidiaphragm, whereas the anterior right hemidiaphragm remains visible.

13. Additional views VIEWS: INDICATIONS: Supine AP Lateral decubitus view
For ill patients and those with multiple injuries
To visualize small effusion
To visualize pneumothorax
Useful for cardiac chamber visualization and left lower lobe visualization
Supine AP
Lateral decubitus view
Expiratory view
Penetrated PA view

15. How to check quality of film?
There are following factors by which we check quality of film:
FACTORS:
Inclusion
Projection
Rotation
Inspiration
Penetration

16. INCLUSION: Chest x-ray should include entire thoracic cage. First rib
Clavicle
Lateral edges of ribs
Costophrenic angles

17. ROTATION: Chest x-ray should not be taken with patient rotated
Spinous process of thoracic vertebrae should lie in the midline.
They should form a vertical line that lies equidistant from the medial ends of the clavicles
EFFECTS OF ROTATION ON RADIOGRAPH:
Become difficult to comment accurately on heart size.
Changes in lung density due to asymmetry of overlying lung tissue

18. More on rotated side

19. INSPIRATION:
Chest x-ray should be taken in second full inspiratory phase.
HOW TO ACESS INSPIRATION:
Anteriorly 6th rib intersect the diaphragm at the mid clavicular line should be included.
9 to 10 posterior ribs should be present.

20. INSPIRATION VIEW
EXPIRATION VIEW

21. PENETRATION
Penetration is the degree to which x-ray pass through the body.
CRITERIA OF WELL PENETRATED CHEST XRAY:
A well penetrated x-ray is one where the thoracic vertebrae are just visible through the heart shadow but bony detail of spine are not usually seen

22. Chest x ray anatomy

23. Lateral view

24. Heart contours

25. LUNGS
Two lungs are soft, spongy and elastic each lung is covered by the visceral pleura and suspended in its own pleural cavity
Two lungs are separated from each other by the heart and great vessels and other structures in the mediastinum
Attached to the mediastinum only by its root
Lungs have 2 major fissure and 1 minor fissure:
MAJOR FISSURES:
Oblique fissure
MINOR FISSURE:
Horizontal fissure
LOBES:
Right lung has three lobes divided by the oblique and horizontal fissure
Left lung has two lobes divided by the oblique fissure only there is no horizontal fissure

26. On the PA chest xray, the minor fissure divides the right middle lobe from the right upper lobe (A) and is sometimes not well seen. There is no minor fissure on the left. The major fissures are usually not well seen on the PA view because you are looking through them obliquely. If there is fluid in the fissure, it is occasionally manifested as a density at the lower lateral margin.
The left image shows the right minor fissure (A) and the inferior borders (B) of the major fissures bilaterally.  The right image shows the superior border of the major fissures (B) bilaterally.
On the lateral view, both lungs are superimposed.  Think about them separately, the left lung has only a major fissure as shown.   The right lung will have both the major and minor fissure.

28. The patient above has a pleural effusion extending into the fissure.
Which fissure is which?   What is the bright loop near the center of the films?

29. The patient above has a pleural effusion extending into the fissure.
Which fissure is which?   What is the bright loop near the center of the films?

30. can you determine which lobe the pneumonia affects?
The right heart border is silhouetted out.   This is caused by a pneumonia,
can you determine which lobe the pneumonia affects?  

31. Hilum is the wedge shaped area on the central portion of each lung where the
Bronchi
Pulmonary
Arteries
Veins and nerves
leave the lung
IMP POINT:
Left hilar point is usually higher
than right
On chest x-ray we consider zones of lungs.
UPPER ZONE:
Is present up to 2nd intercostal space approximately
MIDDLE ZONE:
From 2nd intercostal space-5th intercostal space
LOWER ZONE:
From 5th intercostals space to onward

32. TRACHEA AND MAJOR BRONCHI
Trachea is a cylindrical tube that extend from the level of cricoid cartilage C6 to T5(carina).
Length cm.
Internal dia 10-18mm.
18-20 cartilaginous rings
Divides at carina into bronchi
Passes to the right of aorta

36. Pleural Effusion

37. Pneumothorax

40. Combining all the structures together
Trachea
sternum
Vertebral body
Rt ventricle
Lft atrium
ribs
Lft ventricle
right hemidiaphragm