It is obvious that a revolution is under way in terms of tissue
restoration. For that reason, money is rapidly flowing into the
sector and results are accelerating. This is great. Most problems
are approaching solvability and the day of the handicapped is ending
inside the lifetimes of even middle aged victims.
It will be a very welcome development and will release a lot of human
energy.
Accidents will always happen and restoration is a welcome option.
Amazing Medical
Advances Heal Wounded Troops
By MARILYNN
MARCHIONE 09/10/12 04:26 AM ET
Tom Cervantes, a
research engineer at the Laboratory for Tissue Engineering and Organ
Fabrication at Massachusetts General Hospital, displays a titanium
frame designed for the reconstruction of a human ear, left, and a
three dimensional plastic ear model, right, at the lab, in Boston.
BOSTON -- Scientists
are growing ears, bone and skin in the lab, and doctors are planning
more face transplants and other extreme plastic surgeries. Around the
country, the most advanced medical tools that exist are now being
deployed to help America's newest veterans and wounded troops.
_In Los Angeles,
surgeons used part of Michael Mills' forehead to rebuild his nose
after a bomb disfigured him in Iraq.
_In Pittsburgh,
doctors used an experimental therapy from pig tissue to help regrow
part of a thigh muscle that Ron Strang lost in a blast in
Afghanistan.
_In Boston, scientists
are making plans for the first implants of lab-grown ears for wounded
troops after successful experiments in sheep and rats.
_In San Antonio and
other cities, doctors are testing sprayed-on skin cells and lab-made
sheets of skin to heal burns and other wounds. The ingenuity is
impressive: One product was developed from foreskin left over from
circumcisions.
Much of this comes
from taxpayer-funded research. Four years ago, the federal government
created AFIRM, the Armed Forces Institute of Regenerative Medicine, a
network of top hospitals and universities, and gave $300 million in
grants to spur new treatments using cell science and advanced plastic
surgery.
"The whole idea
is to bring all these researchers together to develop these great
technologies that were in early science to eventually be ready for
the troops," said AFIRM's recently retired director, Terry
Irgens.
Now those who served
are coming home, and projects that once had been languishing in labs
are making strides and starting to move into clinics.
Strang is among those
benefiting. The 28-year-old Marine sergeant from Pittsburgh lost half
of a thigh muscle to shrapnel, leaving too little to stabilize his
gait. "My knee would buckle and I'd fall over," he said.
Now, after an
experimental treatment at the University of Pittsburgh Medical
Center, "I'm able to run a little bit" and play a light
football game with friends, he said. "It's been a huge
improvement."
It's one example of
the "new medicine" in the works for troops. The Associated
Press conducted more than a dozen interviews and reviewed the latest
medical research to measure the progress and extent of novel
treatments under way for wounded warriors. The results point to some
surprising feats of surgery and bioengineering.
___
Growing new ears
Up to a thousand
troops might need an ear, and prosthetics are not a great solution. A
rod or other fastener is required to attach them to the head. They
don't look or feel natural and they wear out every couple of years. A
matching ear grown from a patient's own cells would be a huge
improvement.
"People have been
working on this for 20 years" but haven't been able to overcome
obstacles to making it practical, said Cathryn Sundback, director of
the tissue engineering lab at Massachusetts General Hospital.
Her lab thinks it's
found the solution. Using a computer model of a patient's remaining
ear, scientists craft a titanium framework covered in collagen, the
stuff that gives skin elasticity and strength.
They take a snip of
cartilage from inside the nose or between the ribs and seed the
scaffold with these cells. This is incubated for about two weeks in a
lab dish to grow more cartilage. When it's ready to implant, a skin
graft is taken from the patient to cover the cartilage and the ear is
stitched into place.
Scientists in her lab
have maintained lab-grown sheep ears on those animals for 20 weeks,
proving it can be done successfully and last long-term. They also
have grown anatomically correct human ears from cells. These have
been implanted on the backs of lab rats to keep them nourished and
allow further research. But that wouldn't happen with ears destined
for patients – they would just be grown in a lab dish until they're
ready to implant.
"We've solved
all the technical problems," Sundback said, and now they are
ready to seek approval from the Food and Drug Administration to
implant these into patients – probably in about a year. "It's
amazing how much progress we've made with the AFIRM funding."
___
Bioengineering
muscles, bone and skin
A soldier lucky enough
to keep his arms and legs after a bomb blast still might lose so much
of a key muscle, like biceps or quadriceps, that the limb can't be
used properly. In some cases, "the patient has lost so much
muscle that there's nothing left for the surgeon to sew together,"
said Dr. Stephen Badylak, a regenerative medicine specialist at the
University of Pittsburgh.
He is testing implants
of "extracellular matrix" – connective tissue that holds
cells together – to boost muscle mass. The matrix is thought to
release chemical signals that promote regrowth of healthy tissue
instead of scar tissue.
"It changes the
body from thinking, `I need to respond to injured tissue,' to `I need
to rebuild this tissue,'" Badylak said.
The material is
supplied by a private company – ACell Inc. of Columbia, Md. – and
comes from pigs. The immune system tolerates it because it doesn't
contain cells. It comes in multi-layered sheets like slightly stiff
gauze and can be cut or molded to fit the needed shape.
Strang, who lost half
of a thigh muscle, is among the five patients treated so far in an
80-patient study. Doctors wait at least six months after an injury to
make sure all natural healing has occurred, and put patients through
intensive physical therapy before implanting the matrix.
"We want to be
able to say after the surgery that they were as good as they could
be" and that the matrix accounted for any improvement, Badylak
explained.
In early testing,
"They've shown up to 10 to 20 percent improvement" in
strength of the muscle after treatment, said Irgens, the director of
AFIRM, which funded some of the early work. The Department of Defense
is sponsoring the study under way now, which includes non-military
patients as well as former troops. The new study is measuring changes
in strength and muscle volume, and doctors are aiming for the kind of
quality-of-life improvement Strang has enjoyed.
In other efforts,
Pittsburgh and Rice University scientists are working on growing bone
to fix jawbone and other facial defects. Researchers at Massachusetts
General and Rutgers University are trying to grow eyelid muscles.
Blindness can result from not being able to close an eyelid.
Doctors also are
testing various ways to make skin. In one method, doctors take a
postage stamp-sized piece of a patient's skin, process it in the lab
and spray these cells onto a burn or other wound. The sprayer device
that is used for this treatment is already licensed in seven
countries, and AFIRM is sponsoring a study aimed at winning U.S.
approval so the treatment can be offered here.
The second approach
uses sheets of skin developed from cells in the lab that originally
came from foreskin after circumcisions.
"That's in
clinical trials now and they're having tremendous results,"
Irgens said.
___
Beyond "bionic
arms" to transplants
For all the advances
that have been made in modern prosthetics, the arms and hands are not
as effective as the legs and feet. Dozens of wounded troops would
rather try a transplant.
The government also
estimates that up to 200 troops might need face transplants, although
Dr. Bohdan Pomahac, a Boston surgeon who has done four face
transplants on non-military patients, thinks only 50 to 100
ultimately will get one.
One reason is the
lifelong drugs needed to prevent rejection. They have side effects
and raise the risk of cancer.
Dr. W.P. Andrew Lee,
plastic surgery chairman at Johns Hopkins University, has been
working to minimize those risks. Previously, at the University of
Pittsburgh, he led hand transplants on five patients with minimal
immune suppression, giving them bone marrow taken from their donors
along with the hands to help them better tolerate the new tissue. All
five patients have done well and four now take just one
anti-rejection drug.
"There's really
no reason to think faces will be any different," he said.
He also showed that
rejection can often be stopped by rubbing on a cream containing
immune-suppressing medicine.
"Skin is the
primary target of the rejection," he explained, so with a hand
transplant, "we can detect rejection much earlier than we can
for organ transplants. The patient literally calls us. They notice a
rash on the skin first thing in the morning. We just tell them to put
the cream on."
With military funding,
a host of doctors are evaluating troops as potential face transplant
candidates. Pomahac told of one man who lost much of his face, jaw
and lips in a bomb blast. Despite 25 operations, he still can't move
one side of his face or lips and drools all the time.
"He walks around
with a towel on his shoulder. It's a major quality-of-life issue,"
Pomahac said.
Advancing
reconstructive surgery
Many troops remain
disfigured or impaired despite multiple reconstructive operations.
Tackling the toughest cases is the goal of Operation Mend, a program
of the UCLA Medical Center, Brooke Army Medical Center in San Antonio
and the Veterans Affairs-Greater Los Angeles Healthcare System.
Army Staff Sgt.
Michael Mills, 47, who lives in Freeport, Minn., northwest of
Minneapolis, is one such patient. He was injured in Iraq in 2005 by a
bomb that left him with major burns and broken bones all over. He
lost a finger and thumb. He has a dozen pins in bones and a plate in
his hip. He was missing part of an ear and part of his nose.
Mills had 10 surgeries
with Operation Mend, including three on his hands. Surgeons repaired
his nose with part of his forehead.
"I'm very happy
with the new look I have now," Mills said. "I don't let my
disability run my life. I run my disability."
Some wounds remain,
though. Mills said he suffers from a mild traumatic brain injury,
depression, anxiety and post-traumatic stress disorder, or PTSD.
Counseling through the Department of Veterans Affairs has helped him
cope, and he said he no longer has flashbacks and night sweats and is
more able to control anger.
"I have more good
days now than I do bad days," he said. Doctors can fix his bones
and his nose, but "they can't heal what's inside," Mills
said. "Only I can do that."
___
No comments:
Post a Comment