[IGSTK-Users] TESTING: A cautionary tale about lack of software quality...

[Luis Ibanez]

The Radiation Boom
Radiation Offers New Cures, and Ways to Do Harm

By Walt Bogdanich
Published: January 23, 2010

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

[...]

Americans today receive far more medical radiation than ever before.
The average lifetime dose of diagnostic radiation has increased
sevenfold since 1980, and more than half of all cancer patients
receive radiation therapy. Without a doubt, radiation saves countless
lives, and serious accidents are rare.

But patients often know little about the harm that can result when
safety rules are violated and ever more powerful and technologically
complex machines go awry. To better understand those risks, The New
York Times examined thousands of pages of public and private records
and interviewed physicians, medical physicists, researchers and
government regulators.

[...]

The Times found that while this new technology allows doctors to more
accurately attack tumors and reduce certain mistakes, its complexity
has created new avenues for error — through software flaws, faulty
programming, poor safety procedures or inadequate staffing and
training.

[...]

“Linear accelerators and treatment planning are enormously more
complex than 20 years ago,” said Dr. Howard I. Amols, chief of
clinical physics at Memorial Sloan-Kettering Cancer Center in New
York. But hospitals, he said, are often too trusting of the new
computer systems and software, relying on them as if they had been
tested over time, when in fact they have not.

[...]

Shortly after 11 a.m., as Ms. Kalach was trying to save her work, the
computer began seizing up, displaying an error message. The hospital
would later say that similar system crashes “are not uncommon with the
Varian software, and these issues have been communicated to Varian on
numerous occasions.”

An error message asked Ms. Kalach if she wanted to save her changes
before the program aborted. She answered yes. At 12:24 p.m., Dr.
Berson approved the new plan.

At 12:57 p.m. — six minutes after yet another computer crash — the
first of several radioactive beams was turned on.

[...]

One therapist mistakenly programmed the computer for “wedge out”
rather than “wedge in,” as the plan required. Another therapist failed
to catch the error. And the physics staff repeatedly failed to notice
it during their weekly checks of treatment records.

Even worse, therapists failed to notice that during treatment, their
computer screen clearly showed that the wedge was missing. Only weeks
earlier, state health officials had sent a notice, reminding hospitals
that therapists “must closely monitor” their computer screens.

“The fact that therapists failed to notice ‘wedge OUT’ on 27 occasions
is disturbing,” Dr. Tobias Lickerman, director of the city’s
Radioactive Materials Division, wrote in a report on the incident. The
hospital declined to discuss the case.

[...]

The software required that three essential programming instructions be
saved in sequence: first, the quantity or dose of radiation in the
beam; then a digital image of the treatment area; and finally,
instructions that guide the multileaf collimator.

When the computer kept crashing, Ms. Kalach, the medical physicist,
did not realize that her instructions for the collimator had not been
saved, state records show. She proceeded as though the problem had
been fixed.

“We were just stunned that a company could make technology that could
administer that amount of radiation — that extreme amount of radiation
— without some fail-safe mechanism,” said Ms. Weir-Bryan, Ms.
Jerome-Parks’s friend from Toronto. “It’s always something we keep
harkening back to: How could this happen? What accountability do these
companies have to create something safe?”

[...]

Government investigators ended up blaming both St. Vincent’s, for
failing to catch the error, and Varian, for its flawed software.

[...]

Timothy E. Guertin, Varian’s president and chief executive, said in an
interview that after the accident, the company warned users to be
especially careful when using their equipment, and then distributed
new software, with a fail-safe provision, “all over the world.”

But the software fix did not arrive in time to help a woman who,
several months later, was being radiated for cancer of the larynx.
According to F.D.A. records, which did not identify the hospital or
the patient, therapists tried to save a file on Varian equipment when
“the system’s computer screen froze.”

The hospital went ahead and radiated the patient, only to discover
later that the multileaf collimator had been wide open. The patient
received nearly six times her prescribed dose. In this case, the
overdose was caught after one treatment and the patient was not
injured, according to Mr. Guertin, who declined to identify the
hospital.

[...]

Two years ago, the state warned medical physicists attending a
national conference that an over-reliance on computer programs might
be leading to mistakes, including patient mix-ups.

[...]

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