ShareThisSometimes it seems as though modern medicine is guided by bigger-than-life technology, dominated by million-dollar machines that scan the brain, resonate through soft tissue or deliver precision doses of radiation.
But at least as much of the high-tech action is happening with miniature medical devices similar in size to -- or merged with -- cell phones and other small wireless gear -- sometimes as small as a grain of rice.
Here's a look at some of the smaller stuff coming out of labs.
At Washington University in St. Louis, computer engineers have linked an ultrasound probe to a Smartphone, creating an imaging device that not only fits in the palm of a hand, but also can transmit the images from and to most anyplace with cell-phone service.
That means getting a head start on medical imaging from ambulances, isolated clinics and even patients' bedsides. This has particular implications for medical care in the developing world, which is short on medical imaging, but is rapidly gaining with cell towers.
At Cornell University, a doctoral student in biomedical engineering, George Lewis, documented his design for a therapeutic ultrasound device that is pocket-sized, battery-powered and which he was able to build for about $100.
It can create sound waves strong enough to cause water to turn into steam. But for medical purposes, the high-energy waves can go after tumors, break up kidney stones or speed up drug delivery in sensitive areas like the brain.
Another new cell-phone application, developed by electrical-engineering instructors and students last year at the University of Washington, is a software program that allows deaf and hard-of-hearing people to talk in sign language over a video-equipped mobile phone.
The technology is needed because American cellular networks have low transmission rates -- about a 10th of the speed available in Europe and Japan -- as well as phones that are often light on processing power.
Jessica DeWitt, a deaf psychology major who helped with the sign-language project, said being able to talk in American Sign Language is superior to text messaging because it's faster and better able to convey emotion.
The key innovation was a program that allows cameras to capture and send images of the hands and eyes quickly, while leaving the rest of the screen at lower and slower resolution.
Tongue piercing might just be a bit of extreme body art for most people, but for a quadriplegic, a magnet implanted or otherwise attached to the tongue offers a new way to control a computer, a wheelchair and other electronic devices.
Researchers at the Georgia Institute of Technology devised the new system and described a prototype last summer.
It works because the tongue is directly connected to the brain by cranial nerves, and thus usually remains mobile when other mobility is lost from spinal-cord injury.
By manipulating a tiny magnet -- about the size of a grain of rice -- at the tip of the tongue, it's possible to move a cursor on a controller mounted near the mouth, allowing manipulation superior to what's possible with existing mouth controls.
And at the Massachusetts Institute of Technology, scientists have designed what amounts to a snitch on tumors -- a tiny implant that can monitor the size and development of a malignancy and whether it is spreading, or about to do so.
The biopsy is the current standard for diagnosing and staging cancer. But a surgically removed tissue sample is frozen in time -- it tells doctors nothing about how a tumor is responding to treatments, whether it's growing or shrinking or spreading to other parts of the body.
The device developed by MIT researchers -- and tested on human tumors implanted in mice -- uses magnetic nanoparticles coated with antibodies that attract specific molecules, in this case a hormone produced by the tumor cells. Using magnetic resonance imaging, the scientists were able to measure the hormone level within the tumor from outside the body for a month.
"What this does is basically take the lab and put it in the patient," said Michael Cima, a professor of materials science and engineering who headed the research team.
The devices could also be set up to monitor whether chemotherapy drugs are reaching tumors, or the acidity and oxygen levels within tumors, both indicators of whether tumors are on the wane or growing. Cima expects that a device calibrated to measure acidity would be the first commercially available application, within a few years.
(E-mail Lee Bowman at bowmanl(at)shns.com)
THE MEDICAL JOURNAL
