Radiology Forums

Charlie · Joined: 01 Jul 2005 Posts: 2 Location: Swansea

I have just started a project looking at the optimisation of Automatic Exposure Controls (AEC) as used in CR applications. One of the aspects that I am interested in is the effect that the introduction of CR into radiology has had on patient dose. I'd be very interested in the forums' experience with CR and how, following conversion from film-screen to CR plates, you found your patient doses changing, if at all. Also, I am looking at possible AEC calibration procedures for CR systems and I wondered whether any forum members had experience in this field and what approach they had? Many thanks for any help you can give!

RadMaster · Site Admin Joined: 09 Aug 2004 Posts: 162

I've had experience in three different institutions and would say that the overall dose is way up. Most of this is due to techs overexposing and allowing the computer to fix the image. Please post your results for others to see.

dxraygirl · Guest

Most vendors have a calibration proceedure to calibrate the AEC. Check with your vendor to see what that proceedure is.

As for my expirerance, in general, when techs overexpose, then don't see a noticable change in the image, yet when underexpose, they see grainy image. So their thought is to "overexpose" which of course WRONG!

What is wrong with a correctly exposed image?! Lets all look at the exposure index numbers!

Just a reminder! Wink

ingvey · Joined: 01 Dec 2005 Posts: 1

We have a CR system by Fuji and when we put it in I could not believe how much dose it took to satisfy the detector plates. Quite simply are dose increased 3 fold. Yes 3 times higher than our Kodak film screen combo required. I dont know how the regulators overlook this but I think its a sad state for our powers that be to allow such a step backwards. So as I went around adjusting are Phototimers to give the amount they required I was sick. And oh yes No ONE wanted to hear about it. They simply asked is it legal? than if so SHUT UP. Never to ask is it ethical. So to this day I think that much less about myself for never making more of an issue about the very high doses we were now using , and all for what/??????????????Thanks
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Michael Buck

iraydee8 · Power User Joined: 14 Oct 2004 Posts: 64 Location: AZ

I cant beleive some of these posts! We use about the same for our CR as we did for our extremity film/screen combo. Example Adult Wrist PA 60KVP @ 2 mas! How can others see an increase in 3 times or more when installing CR?

Puzzeled!
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iraydee8