“Brain fingerprinting,” a truth-detection technique that measures the “p300
wave” of the brain while a subject is shown images relating to a crime, is
currently being used in an appeal to overturn a multiple-murder conviction in
Oklahoma. The method simply detects whether the pattern of information in a
photograph is stored in the brain. In the case at hand, the technique is claimed
to prove that the man convicted of the murders did not know where they took
place, where a body was lying, and other salient facts, therefore he could not
be the murderer. In a previous
case in Iowa, a 24-year-old murder conviction was reversed as a result of
brain fingerprint evidence.

It is not unknown for patients to lie to their doctors — with potentially
devastating results. Perhaps there’s a place for brain fingerprinting in
medicine.

Reference: McCall, Becky (2004). “Brain fingerprints
under scrutiny.” BBC News, February 17.

Early-stage Cancer Diagnosis

A proteomics-based blood test is claimed to detect early-stage ovarian cancer
more accurately than any test available now, and is expected to be on the market
in the next few months. The test “could have a big effect on public health if it
works as advertised,” writes Andrew Pollack in the New York Times, given
the high success rate of current treatments for early-stage cases versus the low
success rate for advanced cases.

But while some cancer experts call the new test a “most important
breakthrough,” in part because it may also be adaptable to other forms of
cancer, others caution that it has not been adequately validated and could lead
to unnecessary surgeries if it should prove inaccurate. At least one study has
found inconsistencies in one of the tests, and Pollack’s article describes that
and other cautionary flags.

Whether or not this particular test is validated, it has served the interests
of science and medicine well by drawing attention to the possibilities from
proteomics and stimulating the aggressive pursuit of problems and solutions. In
other words, this is not the end of the story — it is just the beginning.

Meanwhile, DNAwithPap, a cervical screening test recently approved in the
United States for use in women over 30, combines a standard Pap smear with a
genetic screen for the human papilloma virus (HPV) responsible for most cases of
cervical cancer. Yet the HPV test itself, whose accuracy has been
validated (it detects 97-98 percent of precancerous high-grade lesions) has been
slow to be adopted since its FDA approval in 1999. However, it appears to be
taking off now, reports Laura Johannes in the Wall Street Journal.

Reference: Pollack, Andrew (2004). “New Cancer
Test Stirs Hope and Concern.” New York Times, February 3.

Reference: Johannes, Laura (2004). “Advanced
Pap Test Little Used.” Wall Street Journal, February 3.

Photonic Diagnostics

Biomedical photonic technologies use laser light to non-invasively measure
differences in tissue density to find irregularities that sometimes signify the
presence of diseases. One startup company is seeking capital to develop a
biomedical photonic device to detect dental diseases like periodontitis and
gingivitis, eliminating the painful poking and prodding with a depth-measuring
dental pick.

Reference: McCarthy, Ellen (2004). “Photonics
Tools Could Shine a Light on Diseases.” Washington Post, February
16.