Scanning heads?

Sidney · Joined: 01 Dec 2006 Posts: 73

I just started training in CT so I'll probably be here with questions sometimes!

I'm enjoying it so far and have a question about head CT's. We scan the patient supine and center in the area of the chin and scan caudocranial. We tilt the gantry and from what I understand, this helps decrease exposure to the lens of the eye, correct?

I have a hard time visualizing this because in my mind I picture the lens getting the same amount of exposure whether the gantry is tilted or not. Can someone explain this to me?

Thanks! Remember I'm brand new in CT so I don't know too much so please explain it simply if you can. Smile

papa · Posted: Thu Mar 05, 2009 10:36 am Post subject:

i'm actually working on my second online book for ct. if you click on the link in my signature, it'll take you to my homepage, and my first one is on my download page (i think).

when you angle your tube think about your lateral skull, and imagine that line going between the IAC, and the top of the orbit. that will be your slice. will the lens of the eye recieve scatter radiation? yep. but not as much radiation as if you were to just scan directly through it.

when you angle your gantry, you change the angle of the slice along the "z-axis" or along the patient. as you're angeling out of the orbits, you really are reducing the dose to the eyes.
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papa RT(R)(CT) Mr. Green

Delusional Radiology
never meddle in the affairs of a dragon, for you are crunchy, and taste good with ketchup

Sidney · Joined: 01 Dec 2006 Posts: 73

Thanks! I'll check your your link!