CT Scan "Reset Error" Gives 206 Patients Radiation Overdose

jeffb (2.718) writes "As the LA Times reports, 206 patients receiving CT scans at Cedar Sinai hospital received up to eight times the X-ray exposure doctors intended. (The FDA alert gives details about the doses involved.) A misunderstanding over an 'embedded default setting' appears to have led to the error, which occurred when the hospital 'began using a new protocol for a specialized type of scan used to diagnose strokes. Doctors believed it would provide them more useful data to analyze disruptions in the flow of blood to brain tissue.' Human-computer interaction classes from the late 1980s onward have pounded home the lesson of the Therac-25, the usability issues of which led to multiple deaths. Will we ever learn enough to make these errors truly uncommittable?"

Comments

Re:Will errors ever go away?

[Darinbob]

There is a lot of regulatory oversight of these machines. Even relatively benign devices like ultrasound have a lot of process to ensure safety, and the extremely deadly stuff like radiation therapy seems like 99% process to 1% engineering (and you thought those TPS cover sheets were annoying). Many bugs, even simple GUI mistakes, can escalate throughout the company. Which is sort of what you expect with potentially dangerous equipment.

But at the end of the day, you have to beware of the user. You even have to design around the user, to ensure the user does not make a mistake. Allowing the user to make a mistake can often be considered a bug. Using radiation therapy machines is a constant stream of "are you sure?" messages. I heard one story where a machine had two widely separated buttons, both of which had to be held down for safety reasons to perform a certain operation, and then someone discovered a customer that kept a weight near the machine for use on the second button rather than having a colleague help.

This is absolutely one area where you don't want the end user taking control and changing the software or rewiring the machine. You'll never see a GPL license come with these machines.