The Cyberknife (which uses an accelerator) works somewhat like the Gammaknife (which uses 201 cobalt-60 sources of approximately 30 curies (1.1 TBq) each), in that it *intersects* a great many relatively low intensity beams at the target point(s) – the difference being that the Gammaknife only combines beams in space (firing them all at once), while the Cyberknife combines beams using both space and time – it only has a single beam to work with at any one time, so needs to move it around constantly, to achieve the same effect as the Gammaknife.....
(there is a nice video of the Cyberknife here in Montreal – in French: http://www.youtube.com/user/chumontreal#p/search/0/zRawBnQQGF0 )
Given all the motion and relatively low beam intensity, it seems impractical to use detectors to stop a treatment procedure.
But maybe they do – I don’t know.
Certainly there must be a variety of safety features included with such machines – not to mention extensive training for the operators.
But things can still go wrong....
----- Original Message -----
From: Rod Adams
Sent: Sunday, January 24, 2010 9:10 AM
Subject: Re: [cdn-nucl-l] Radiation Offers New Cures, and Ways to Do Harm
It seems to me that part of the cautionary tale is the value of simplicity. Many of the reported accidents occur due to machine failures and software glitches.
Makes me wonder just why we have moved so far away from simple sources with focus lenses to provide correct gamma exposure based on time and distance.
Why has the medical device industry developed such complex and expensive equipment to substitute for what is essentially a simple and predictable process, like the decay of radioactive isotopes?
On Jan 24, 2010, at 8:59 AM, Jerry Cuttler wrote:
The hazard in radiation therapy is not from low dose, but from overdose cause by human error.
January 24, 2010
The Radiation Boom
Radiation Offers New Cures, and Ways to Do Harm
As Scott Jerome-Parks lay dying, he clung to this wish: that his fatal radiation overdose — which left him deaf, struggling to see, unable to swallow, burned, with his teeth falling out, with ulcers in his mouth and throat, nauseated, in severe pain and finally unable to breathe — be studied and talked about publicly so that others might not have to live his nightmare.
No virus found in this incoming message.
_______________________________________________ cdn-nucl-l mailing list cdn-nucl-l@mailman.McMaster.CA http://mailman.McMaster.CA/mailman/listinfo/cdn-nucl-l