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Implants may help Reeve breathe

Christopher Reeve, the actor who has been paralyzed and on a respirator since breaking his neck in a riding accident eight years ago, has had electrodes implanted in his diaphragm in an effort to restore his ability to breathe naturally.

The results are extremely promising, said Dr. Raymond Onders, who performed outpatient surgery on Reeve at University Hospitals of Cleveland on Feb. 28. He can breathe without the respirator for more than two hours at a stretch compared with 10 minutes before the operation, Onders said.

As his diaphragm muscles regain strength over the next couple of months, Reeve may be able to wean himself permanently from the respirator.

While breathing on his own, he is regaining the ability to talk normally. And when he is breathing more normally — not through the ventilator's hole in his throat — his sense of smell is functioning for the first time since his accident.

Reeve, who was expected to describe his experience at a news conference today in Cleveland, is the third person to receive the experimental treatment, called diaphragm pacing via laparoscopy, which has been approved by the Food and Drug Administration for use in 35 patients.

In the treatment, tiny wires are threaded through small incisions directly into the diaphragm. Surgeons use a tubelike instrument that causes very little tissue damage and patients go home the same day of the operation.

If the federal agency approves the surgery, it is expected to cost about $10,000. It is now financed by the agency, the Department of Veterans Affairs and other donors for use in five patients. Hospital officials said that $2 million to $3 million more would be needed to complete the trial.

One of Reeve's major goals has been to get off the respirator, said Dr. John McDonald, the neurologist at Washington University School of Medicine in St. Louis who set up an intensive exercise program that has enabled Reeve, to wiggle his extremities, to sit up partly by himself and, with great effort using neck muscles, to breathe for short periods without a respirator.

"Once Chris can breathe naturally on his own, and everything so far says he will, his exercise program should work even better," McDonald said.

Reeve was a candidate for the treatment because the phrenic nerves that control breathing, which run from the spinal cord to the diaphragm, were not injured by his fall. But the nerves meet the spinal cord below the site of Reeve's injury, so they could no longer receive signals from the brain stem where breathing is initiated. As a result, they stopped functioning.

Many years ago, doctors realized that if these nerves could be activated artificially, more natural breathing might be restored.

The new technique involves running wires from a control box worn outside the body to electrodes on the diaphragm.

When the electrodes are stimulated by current, the diaphragm contracts and air is sucked into the lungs. When the nerve is unstimulated, the diaphragm relaxes and air moves out of the lungs. About 75 percent of natural breathing is carried out by this process, with the rest under the control of other muscles.

The control box sends a signal to the electrodes on the diaphragm 12 times a minute, a normal breathing rate.

Surgeons have used similar methods before, but they required invasive surgery that involved opening the chest cavity.

"Chris felt it was a drastic and dangerous procedure that was not worth the risk," McDonald said. When he heard about the less invasive and far less expensive procedure developed by biomedical engineers in Cleveland, he asked to participate.

During the surgery, Onders made four dime-size holes in Reeve's abdomen and threaded a specially designed laparoscope up into his left and right diaphragm muscles. Then he used a mapping technique to find the exact area, called the motor point, where the phrenic nerve contacts the diaphragm. When this motor point is activated, the entire diaphragm contracts.

The location of the motor point is not obvious, said Dr. Anthony DeMarco, program director for the experiment at University Hospitals of Cleveland.

The probe is inside the muscle but the nerve can be almost anywhere on the other side of the muscle wall, he said. By stimulating different muscle areas, the surgeon looks for the region that responds most strongly to electrical stimulation. These areas are different in each person.

Upon finding these points in Reeve, Onders implanted two electrodes on each side of the diaphragm and ran connecting wires out to Reeve's chest wall. When the electrodes are stimulated with a mild current, Reeve takes a natural breath.

After resting at his home in New York for a week, Reeve returned to Cleveland on Sunday to undergo training to restore strength in his diaphragm. Onders said he hoped that Reeve would be able to wean himself completely from the respirator in 12 weeks.

That would greatly improve his life, McDonald said. The machine is noisy and the hole cut in the throat to attach the breathing tube is a huge portal for infection. It is difficult to talk while on a respirator, but without it Reeve can talk normally, though his voice is still weak.

So far, it has not risen above a whisper, his doctors said, but it will soon come back. Able to breathe naturally, Reeve could smell scents placed under his nose — oranges, peppermint and coffee.

About 200 to 300 spinal cord patients a year may be eligible for the surgery, Onders said. It could also benefit many patients who need to be on respirators for long periods.

Of the two earlier recipients in the current trial, one has been free of a respirator for more than two years. The electrodes failed to help the second person, whose diaphragm and nerves were more atrophied than doctors realized before surgery.

Research for the technique was also carried out at Case Western Reserve University in Cleveland, which is separate from University Hospitals.

Reeve was to return home on Thursday.