2007 September 02 Sunday
High Intensity Ultrasound Seals Bleeding Lung Like Star Trek Tricorder

Leonard "Bones" McCoy's medical tricorder couldn't do everything. After all, it didn't detect any readings from Trelane. But the tricorder didn't just have the ability to scan. The tricorder could heas as well (e.g. the doctor in Voyager used his tricorder to heal a "hairline fracture of the pre-maxilla bone" after Seven clobbered an alien). Well, the US Department of Defense is funding development of a portable high intensity ultrasound sound wave device to stop internal bleeding.

Engineers at the University of Washington are working with Harborview doctors to create new emergency treatments right out of Star Trek: a tricorder type device using high-intensity focused ultrasound rays. This summer, researchers published the first experiment using ultrasound to seal punctured lungs.

"No one has ever looked at treating lungs with ultrasound," said Shahram Vaezy, a UW associate professor of bioengineering. Physicists were skeptical it would work because a lung is essentially a collection of air sacs, and air blocks transmission of ultrasound. But the new experiments show that punctures on the lung's surface, where injuries usually occur, heal with ultrasound therapy.

"The results are really impressive," Vaezy said. He cautions that this is still in the early stages and the technique is not yet being tested on humans.

A focused beam of ultrasound could kill tumor cells better than x-rays because the heat of the ultrasound beam would only occur at the focus point. The intermediate tissue the ultrasound beams would pass through wouldn't suffer damage the way tissue gets damaged by radiation beams.

High-intensity focused ultrasound is now being investigated for a number of different treatments. It promises "bloodless surgery" with no scalpels or sutures in sight. Doctors would pass a sensor over the patient and use invisible rays to heal the wound. Researchers are exploring the use of high-intensity focused ultrasound - with beams tens of thousands of times more powerful than used in imaging - for applications ranging from numbing pain to destroying cancerous tissue.

In this case, lenses focus the high-intensity ultrasound beams at a particular spot inside the body on the patient's lungs. Focusing the ultrasound beams, in a process similar to focusing sunlight with a magnifying glass, creates a tiny but extremely hot spot about the size and shape of a grain of rice. The rays heat the blood cells until they form a seal. Meanwhile the tissue between the device and the spot being treated does not get hot, as it would with a laser beam.

"You can penetrate deep into the body and deliver the energy to the bleeding very accurately," Vaezy said. Recent tests on pigs' lungs showed that high-intensity ultrasound sealed the leaks in one or two minutes. More than 95 percent of the 70 incisions were stable after two minutes of treatment, according to results published this summer in the Journal of Trauma.

The University of Washington press release makes no mention of industry partners. But it does mention Department of Defense funding for this work. Well, a Seattle area company AcousTx Corporation, is working on development of an ultrasound bleed-stopping device for the Defense Advanced Research Projects Agency (DARPA) for DARPA’s Deep Bleeder Acoustic Coagulation (DBAC) program. Well it turns out that the DOD is so keen to get this technology that DOD is funding two different Seattle area teams to compete to achieve this goal.

The researchers at AcousTx, a small ultrasound company in Seattle, are funded by a four-year contract, worth up to $30 million, from the U.S. Defense Advanced Research Projects Agency (DARPA).

To underscore the pressing need, the agency gave another $21 million to a competing group, a partnership of Philips Research and the University of Washington's Center for Industrial and Medical Ultrasound.

"If this were to work, just think — just think — about the value it would have as a lifesaving device," said Michael Sekins, AcousTx vice president of research and development.

But how do they know where to focus the beam? They can't heat the entire chest without basically cooking the bleeding person to death. So how to locate the locations with dangerous bleeds?

By Randall Parker    2007 September 02 10:06 AM   Entry Permalink | Comments (2)
2007 April 22 Sunday
Abdominal Surgery Through Orifices

No need for cutting into the abdominal wall of muscles when doing surgery.

Doctors in New York have removed a woman’s gallbladder with instruments passed through her vagina, a technique they hope will cause less pain and scarring than the usual operation, and allow a quicker recovery. The technique can eliminate the need to cut through abdominal muscles, a major source of pain after surgery.

The operation was experimental, part of a study that is being done to find out whether people will fare better if abdominal surgery is performed through natural openings in the body rather than cuts in the belly. The surgery still requires cutting, through the wall of the vagina, stomach or colon, but doctors say it should hurt less because those tissues are far less sensitive than the abdominal muscles.

A couple of the surgeons quoted in the article claim to find this approach disgusting. But anything that makes surgery less traumatic seems like a good idea for all of us. Of course half of us aren't women. But never fear. Appendix removal through the mouth anyone?

At Stanford, Dr. Myriam J. Curet, a professor of surgery, said, “It has some promise, and there’s a lot of interest in the surgical community, a lot of attention being paid to it as a wave of the future.”

Dr. Curet acknowledged that the idea was a bit disturbing at first, and said that even an audience of doctors shuddered at the video of the appendix being pulled out through the patient’s mouth.

I'm reminded of the South Park episode where the adults got it into their heads to reverse the normal direction of passage of food through the body.

In animals researchers have removed many other organs by mouth or vagina.

Dr. Bessler said he and his colleagues had been doing practice operations in the laboratory on pigs for the past year, removing gallbladders, spleens, kidneys and stomachs through the mouth or vagina.

You might hope you never have to have an organ removed either with an abdominal incision or via some orifice. But once the growth of replacement organs from stem cells becomes commonplace surgery for installation of replacement parts will become quite desirable. Got old lungs which prevent you from doing sustained aerobic activities? Put in some replacement lungs. Why not replace a few other organs in the same surgical session and recover into a more vigorous and healthy person?

Gene therapies and stem cell therapies will reduce the need for surgery. But then we'll live longer and more parts will wear out and fail. So we'll end up needing some surgery. Small insertable surgical devices will continue to reduce the size of surgical incisions. But in the longer run I'm expecting nanodevices to do a lot of surgery. Even larger yet miniature devices which aren't connected to the outside via a cable will become maneuverable as remote-controlled surgical devices. Imagine swallowing devices that pass through intestinal walls and move to an organ. Then they could transmit information out to a surgeon who'd use remote controls to direct chopping pieces out of organs and reconnecting remaining pieces.

What I wonder: Will we eventually be able to grow replacement organs within us and by doing so eliminate the need for surgery to insert replacement organs?

By Randall Parker    2007 April 22 03:49 PM   Entry Permalink | Comments (8)
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