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A Chest X-ray as an Example - 1
This a good starting point, as we are familiar with the thorax.
This is a PA view of the thorax.
Note :
§The air outside the body is black.
§Oval A : bone, a part of the clavicle. Can you distinguish two white bands with a darker area in this bone? The centre of the bone is “spongy”, the outer part is solid.
§In the oval B, the end of the clavicle has a large centre of “spongy” bone. The overall picture is therefore a bit darker.
§At C, a rib is ‘flat across’ the beam.
§At D, a greater length of the curve of the rib is across the beam, therefore it is whiter than at C.
A
B
C
D
Key Points : Think of the anatomy of the structure being viewed. Even bone can have different appearances depending on the thickness it presents to the X-ray beam.