Departments: Resource Central
Where to go for more information on the topics discussed in this issue of Neurology Now and for a directory of patient advocacy organizations.
CPAP: The most effective treatment for obstructive sleep apnea (OSA), in which the tongue and soft palette relax against the back of the throat and block the airway, is continuous positive airway pressure (CPAP). This treatment involves a bedside machine that blows a stream of air through a tube into a mask worn by the sleeper. The air holds the airway open, splitting it, and allows the sleeper to breathe normally.
A different kind of sleep-disordered breathing known as central sleep apnea can result from congestive heart failure, stroke, high altitude, certain medications, or other problems that weaken the signals from the brain instructing the muscles of the diaphragm to contract and draw air into the lungs. Some people with central sleep apnea may benefit from ordinary CPAP, but others may require a more sophisticated type of machine that delivers bi-level positive airway pressure (BPAP). With BPAP, two separate pressures are used: a stronger stream of air is delivered into the airway when the sleeper inhales and a weaker stream when the sleeper exhales, simulating the breathing cycle. This encourages the sleeper to take more air into the lungs.
Mandibular Advancing Devices: A person with OSA can wear a special device resembling a football mouth guard that repositions the lower jaw forward slightly, discouraging the tongue from relaxing against the back of the throat. In addition to reducing mild to moderate OSA, these devices also reduce snoring significantly. The device does not help people who have central sleep apnea, however.
Surgery: Several surgical procedures have been shown to help OSA:
* Surgically inserting palatal implants—synthetic rods embedded in the soft palate, stiffening it—can sometimes help prevent the soft palate from collapsing. This surgery is primarily helpful for snoring.
* Uvulopalatopharyngoplasty and laser-assisted uvulopalatopharyngoplasty involve surgery to remove tissue from the back of the mouth, widening the airway. This should be offered only after a careful assessment. In addition, since the tissue of young patients will become thinner and more collapsible as they age, this procedure does not guarantee that OSA will not recur.
* Maxillary mandibular advancement is a surgical procedure that involves fracturing the lower and upper jaw and moving them forward. This produces a longerlasting change, making it more appropriate for younger patients who are good surgical candidates and are absolutely unable to tolerate their CPAP machines.
* A less popular surgical option is glossectomy, which involves surgery to remove a portion of the tongue, increasing the size of the airway.
* Other more radical surgeries, such as opening a hole in the trachea in an effort to improve airway flow, are reserved for patients with life-threatening OSA who cannot tolerate positive pressure therapy and/or have failed other surgical options.
Hypoglossal Nerve Stimulation: One therapy in development involves implanting a device known as a hypoglossal nerve stimulator under the skin of the upper chest, connected to a wire that stimulates the hypoglossal nerve during sleep. This maintains the tongue's muscle tone, preventing it from relaxing against the back of the throat.