1 - Intro Chest Radiography

Density/whiteness ranking in CXR

(From white to black)

#1 Metal

#2 Bone

#3 Soft tissue(Like the heart) + Water

#4 Fat

#5 Air

Most preferred positions for a CXR

• Upright, posteroanterior(Aka light shone from behind, film rested in the front)

  • If not possible, then a upright anteroposterior(light from in front, film on the back) is second

    • Lastly/least preferred is a supine anteroposterior CXR

Why is upright posteroanterior the most preferred position for a CXR?

1. Scapula doesn’t block the view

2. Air in the stomach rises up so we can see the air-fluid level in stomach

3. Heart stays proper size(enlarged if we lie down)

Projection-Lordotic view

Anterioposterior view angled 20-45 up to avoid the clavicle

Projection-Decubitus view

Lying on your side, used to detect effusion, eg. suspected right pleural effusion would mean we tell the patient to lie in a right decubitus position

How do we measure penetration and make sure we aren’t using too much or too little exposure?

Look at the lower part of cardiac shadow and see if we can see the vertebral bodies. We should be able to see them without being able to see their details

To measure if the patient did proper inspiration before getting their CXR taken, we look at

Whether or not we can see 10 posterior ribs

Hidden areas on CXR

1. Apex of the lungs: Behind clavicles

2. Hilum/root of the lungs: Behind pulmonary vessels

3. Retrocardiac area

4. The bottom of the lungs: Hidden behind the liver/top of diaphragm

Name the numbers

1. Pulmonary Vein

2. Lymphs

3. Pulmonary Artery

4. Bronchiole

5. Terminal bronchiole

6. Alveoli

   
   

What does ปื้น and เส้น indicate in a CXR?

ปื้น: Airspace opacification, aka things in the alveoli, like water from HF(Severe), pus from pneumonia, blood from hemorrhage, and cells from a carcinoma

เส้น: Interstitial opacification, aka things in the interstitium like water from HF(Beginning), TB, mycoplasma