Millions of Americans suffer from obstructive sleep apnea, and to conquer the disorder the vast majority of them rely on a technology developed more than 30 years ago - a machine that blows air through a hose into a mask worn during the night.

Physicians say the apparatus - the continuous positive airway pressure device, known as CPAP - remains the first line of defense against the potentially life-threatening condition because it's effective and noninvasive. But many patients find it awkward and uncomfortable, making the quest for an alternative both practical and profitable.

A number of new treatments for sleep apnea are in the works.

"We're all trying to come up with better diagnostic and treatment methods for obstructive sleep apnea," said Dr. Clete Kushida, medical director of the Stanford Sleep Medicine Center, the first sleep center in the country.

Sleep apnea affects some 18 million Americans. The disorder occurs when a person's breathing is interrupted during sleep, usually because soft tissue collapses in the back of the throat, blocking the airway. Untreated, sleep apnea can increase the risk of high blood pressure, cardiovascular disease and daytime accidents resulting from drowsiness.

The continuous positive airway pressure device works for a majority of people with sleep apnea, but some physicians say almost half of their patients don't use it regularly.

Promising devices

Now, two Minnesota medical device makers have received clearance from the U.S. Food and Drug Administration to test implantable devices designed to treat people whose sleep apnea is caused by tongue obstruction. The devices, both implanted in the upper chest, work to stimulate a nerve in the patient's neck to push the tongue forward and open the airway.

Inspire Medical Systems received approval in November to start clinical trials, and Apnex Medical Inc. just received the go-ahead this week. The California Sleep Institute in Palo Alto is one of 10 centers nationwide involved in a clinical trial to test Inspire's device.

A San Diego company, ImThera Medical Inc., recently completed trials in Europe of a slightly different implantable neurostimulation device and is requesting approval from the FDA to conduct U.S. trials.

"We're looking for stuff that's as good as what we have or better, but less invasive and easier for patient to tolerate," said Dr. Donald Sesso, a head-and-neck surgeon at the California Sleep Institute in Palo Alto, who is now enrolling patients in the trial and hopes to start surgically implanting Inspire's device this fall.

Sesso said he's intrigued by Inspire's device, which he likened to a pacemaker, because early tests look promising. It does its job without waking up the patient, unlike earlier versions of similar technology, Sesso said.

But the device won't work for everyone, only those whose disorder is caused by tongue obstruction.

A range of treatments

For some patients, sleep apnea is caused by problems with the nose or palate or a combination of issues. In those cases, treatments can be as complicated as surgery to remove excess tissue in the mouth and throat or reset the lower jaw or as simple as prescribing a mouthpiece.

Surgeries don't always work.

"There are some improvements, but the surgery overall is only about 50 percent effective," said Dr. Vadim Kagramanov, chairman of the sleep medicine division of the Palo Alto Medical Foundation. Kagramanov said he's tried various new treatments, such as an external nasal device called Provent, but has had better success with the continuous positive airway pressure device.

The Stanford Sleep Medicine Center is involved in several studies.

For people who suffer from sleep apnea, the treatments can be as individual as the patients themselves.

Christian Roth, 34, who was diagnosed with severe sleep apnea last summer, tried to use the continuous positive airway pressure device for a couple of months but could rarely get through the night using it. Surgery became his next best option.

"I was so young, and I didn't want this chronic condition and have to strap myself up with CPAP for the rest of my life," said the San Jose resident.

Roth's doctors had told him he may need several surgeries to correct the problem, but one surgery to remove his tonsils, correct a deviated septum and reduce the tissue in his nostrils did the trick.

"It's been great," he said. "My blood pressure is down, and I have much more energy."

Dusting off CPAP

When Les Besser was diagnosed with obstructive sleep apnea 10 years ago, he tried using the CPAP machine but found it irritated his sinuses, so he threw it in the closet.

But two years later, after experiencing high blood pressure caused by his sleep problems, the 75-year-old Los Altos resident dusted off the device and started using it. He doesn't like it, but he's reluctant to undergo major surgery and admits the CPAP device is better than risking a heart attack or stroke.

Besser, a retired engineer and entrepreneur, is the moderator of a Silicon Valley support group for sleep apnea sufferers and has tested numerous CPAP machines in search of a more comfortable device.

"So far none of our grandchildren have seen it," Besser said of his CPAP machine. "But I think they'd be scared to death if they did."

Obstructive sleep apnea

What is sleep apnea? A common sleeping disorder characterized by pauses in breathing or shallow breaths that interrupt sleep.

What are the symptoms? Most people are unaware of these nighttime disruptions, but common symptoms include snoring, fatigue and problems with attention, mood and memory.

Who is at risk? Anyone can get sleep apnea, but those at higher risk include people over 40, especially men, as well as those who are overweight and have a family history of sleep apnea.

Can it be dangerous? Yes. Sleep apnea increases the risk of high blood pressure, stroke, heart problems and driving accidents.

How is it diagnosed? Through a formal sleep study, or polysomnography, a diagnostic test that involves placing sensors on the body that are monitored during the night.

How is it treated? Weight loss or behavior changes, such as reducing alcohol consumption, can be helpful. The most common treatment involves a breathing device known as continuous positive airway pressure (CPAP), but other therapies include mouthpieces, surgery to the jaw or to remove excess tissue and, more recently, implantable devices that can change the position of the tongue.

More information

Information about Inspire Medical Systems' device, which is being tested at the California Sleep Institute in the Bay Area and nine other U.S. sites, can be found at or by calling (888) 708-5046.

E-mail Victoria Colliver at