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Fatal Dose – Radiation Deaths linked to AECL Computer Errors (1994)

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Re: Fatal Dose – Radiation Deaths linked to AECL Computer Errors (1994)

#2
The Therac-25 case study is a tragic one, but fortunately it is not forgotten.

I work on medical devices (and have worked on radiotherapy devices previously) and the standards for quality systems and regulatory hurdles (which I occasionally see bemoaned here on HN) are there with good reason. In fact, Therac-25 is often cited when training new hires on quality (as required with any ISO-13485 compliant QMS).

Re: Fatal Dose – Radiation Deaths linked to AECL Computer Errors (1994)

#5
>>As a result of the Therac-25 accidents, the FDA now requires documentation on software for new medical and other products: a paper trail, in other words, that can be examined by an independent body and retraced for flaws.Anyone have any idea if this can be looked at by the end user? I'm not a radiation technologist of the flavour mentioned in the article, I'm on the diagnostic side. I use an MR scanner with numerous software bugs that I have reported but which remain. Similarly, the scanner can be made to display data which it says it is going to use in the next scan, but which it isn't. I suspected a bug and found the way to reproduce it. My last email listed 24 similar bugs (I've found more since) but other than a "thanks, we will forward this on" there has been no reply or comment. It is hard to imagine when this could be a safety issue, but it is a waste of valuable time, it is a waste of money and it's frustrating when I have gone to the trouble of working out the exact way of creating the issues. If anyone is interested, the interface is so god awful that instead of having an on off button or switch interface, the scanner gets the user to type 1 or 0 for on and off into a text field. Some fields take other values like 1, 2 and 3. Some take decimal values like 0 to 1 in 0.1 increments. There is no pattern to what the user is expected to type. Yuck. This data is not properly sanitized either, and you can make the scanner say its "doing" something it's not. Type in 1.999, and error message appears, the field corrects to 2.0 but the scanner does the thing that a setting of 1 would produce. These sorts of bugs occur all over the place.

Edit: The "thanks" email is the most positive I've ever got, my previous reports were me with statements like "we have some very experienced users who haven't had this issue" when there were clear safety problems with earlier scanner implementations (The scanner was producing axial slices at a location different to where I asked for them to be, on a spine patient due in theatre - good luck operating on the correct vertebral level). Its FDA approved and its on the latest software release. I have undergone manufacturer training and have had additional training half a dozen times at my request and at the manufacturers request after my bug reports were met with "you're doing it wrong". I'm not, the software is buggy and I have some excellent and amazing screen shots and camera phone video of the bugs in action.

Re: Fatal Dose – Radiation Deaths linked to AECL Computer Errors (1994)

#6
post #2

The Therac-25 case study is a tragic one, but fortunately it is not forgotten. I work on medical devices (and have worked on radiotherapy devices previously) and the standards for quality systems and regulatory hurdles (which I occasionally see bemoaned here on HN) are there with good reason. In fact, Therac-25 is often cited when training new hires on quality (as required with any ISO-13485 compliant QMS).

Diagnostic imaging guy here - we point our recruits to this, balding patients when doing diagnostic tests shouldn't happen. http://www.ajnr.org/content/31/1/2.full

Re: Fatal Dose – Radiation Deaths linked to AECL Computer Errors (1994)

#7

>>As a result of the Therac-25 accidents, the FDA now requires documentation on software for new medical and other products: a paper trail, in other words, that can be examined by an independent body and retraced for flaws. Anyone have any idea if this can be looked at by the end user? I'm not a radiation technologist of the flavour mentioned in the article, I'm on the diagnostic side. I use an MR scanner with numero…

Time to get in touch with the press. 25 bugs in something health-critical? They'll have a field day.

Re: Fatal Dose – Radiation Deaths linked to AECL Computer Errors (1994)

#8
One of the more infamous classes in Computer Science at Cal Poly SLO is "Professional Responsibilities", is taught by Dr. Clark Turner. The class delves into Therac-25, and similar cases that have happened since. I found the class really interesting because it does make you question and think about the ethics of what you are building and what others have built.

Knowing about, and thinking about, the ACM Code of Ethics, Stuxnet, Therac-25, the Windows Security Patch Policy, and other problems our programming culture have come across is important. Realizing that the code we write can affect people in both positive and negative ways on a long and short term scale is something that can change both your product and how you build a product.

Re: Fatal Dose – Radiation Deaths linked to AECL Computer Errors (1994)

#9
post #7

>>As a result of the Therac-25 accidents, the FDA now requires documentation on software for new medical and other products: a paper trail, in other words, that can be examined by an independent body and retraced for flaws. Anyone have any idea if this can be looked at by the end user? I'm not a radiation technologist of the flavour mentioned in the article, I'm on the diagnostic side. I use an MR scanner with numero…

Time to get in touch with the press. 25 bugs in something health-critical? They'll have a field day.

My hope (which is steadily fading) was to make contact with someone in the development team to suggest a few improvements and show a few of the more obscure bugs that I haven't reported. I'd love to be able to positively influence the development. There has been limited "end user" input as far as I can tell and some small changes would make the platform so much more powerful. The upside to the lack of communication is that I've begun leaning to code and use my code on my phone to bypass the scanner's crap - without the poor scanner interface I wouldn't have done this. I should note that my basic code is truly awful to look at, although it works reliably and does a better job of its small task than the multimillion dollar console I use.

Re: Fatal Dose – Radiation Deaths linked to AECL Computer Errors (1994)

#10

>>As a result of the Therac-25 accidents, the FDA now requires documentation on software for new medical and other products: a paper trail, in other words, that can be examined by an independent body and retraced for flaws. Anyone have any idea if this can be looked at by the end user? I'm not a radiation technologist of the flavour mentioned in the article, I'm on the diagnostic side. I use an MR scanner with numero…

GE scanner, by chance? I've heard their software is pretty terrible compared to their competitors.
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