Dozens of patients injured by stray radiation beam | Hacker News Reader

Dozens of patients injured by stray radiation beam

msnbc.msn.com

15 pointsedw51920 comments

I've seen these devices in action. There is zero visual feedback when they are operating. Would it be so hard just to have a variable brightness indicator light coupled with a radiation detector so the operator or assistant would say "damn, is it always that bright?"

Something, anything that would give the operator some kind of visceral feedback consistent with the output.

It mentioned that there is a light field that is supposed to show where the radiation will hit, but the mount blocked it - but didn't block the radiation.

"To work around that problem hospitals needed to, as one medical physicist put it, essentially trick the machine into thinking it was using a different attachment, which it did recognize. To do that, users had to enter additional data into the SRS system."

Scary.

Very. Presumably they're paying for hefty support contracts as part of the purchase of these machines - I cannot imagine that the developers recommended medical end-users alter the system. If so they seem culpable.

Meanwhile, untrained TSA employees are rolling out hundreds of new radiation scanners at airports. The technology is different but TSA malfunctions are simply a matter of time...

While I agree with the general thrust of your comment, the machines used by the TSA are not "focused" in the same way. It would take much greater effort to create hazardous conditions like these patients experienced.

TSA scanners are focused more than a traditional x-ray, because they target skin tissue to produce the image.

The TSA systems (at least the backscatter X-ray) do use a focussed moving beam to build up an image. They rely on the continual movement of the beam to limit the dose.

There are a number of safety systems to prevent the machine leaving the beam on should the mechanism stick.

And of course they are operated by the finest trained experts with a comprehensive background in nuclear physics and the ability to react in the fraction of a second before a notifiable dose was delivered

I love to hate on TSA as much as the next guy, but the "technology difference" to this medical device is the difference between a nerf gun and a sniper rifle.

The point is that medical professionals can't properly handle a sniper rifle, do you trust TSA employees with any level of radiation deployed on a massively larger scale?

This kind of fearmongering is even worse than what the TSA does. Sure, the X-ray machines could mysteriously fail in such a way as to irradiate you. But it's very, very, very unlikely.

(What's the difference between backscatter x-ray and linear accelerators for surgery? The backscatter machine is designed to emit low levels of radiation. The linear accelerator is designed to send a beam of damaging radiation into the subject. The problem that the article describes was that the radiation beam designed to damage stuff was pointed at stuff that it shouldn't have been pointed at.)

Also, doctors are supposed to be skilled operators, and their machines are designed for that. TSA agents are not supposed to be skilled operators, so the machines they use don't have any knobs that they can tweak incorrectly.

Anyway, not worried about this, sorry.

I'm guessing submitter discovered this in The Risks Digest. I subscribed by RSS recently and I am finding it interesting. There is a healthy culture of informed paranoia in plenty of other disciplines aside from software that one can learn from.

http://catless.ncl.ac.uk/risks

A hilarious article about f16 testing is what turned me on to it in the first place: http://catless.ncl.ac.uk/Risks/3.44.html#subj1

Original article:

http://www.nytimes.com/2010/12/29/health/29radiation.html?_r...

It's the same text BTW.

> The mistakes in Evanston involve linear accelerators — commonly used for standard radiation therapy — that were redesigned by the manufacturer, Varian Medical Systems, so they could also perform SRS. As the devices became more versatile and complex, problems arose when vital electronic components could not communicate with one another.

WTF, this is eerily and specifically reminiscent of Therac-25. Did they learn nothing?

I hope that the families of the unfortunate victims of these overdoses allow the affected tissues to be studied (with appropriate compensation), so that treatments can be devised if similar injuries occur in the future, and general medical knowledge increases.

Echos of Therac-25. Not nearly as bad... no one's dead yet.

Oh, oh! I tried to find a book I have with the Therace-25 case study. If I recall, race conditions tripped the integer byte datatype and fired radiation at that point in time.

Ten years later, I've meant to finish the book. It's in a box somewhere.

This guy is dead.

http://www.nytimes.com/2010/01/24/health/24radiation.html

Actually, if you look at the author's work, he's been covering radiation overdose all year.

http://topics.nytimes.com/top/reference/timestopics/people/b...

I'll trust UCSF over TSA's bullshit any day of the week.

http://news.ucsf.edu/news-briefs/details/ucsf-scientists-spe...

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