Polysomnography

Sleeplessness, daytime drowsiness, snoring, and frequent nighttime awakenings are all possible results of sleep disorders. The causes of these disorders can range from stress or drug induced insomnia to sleep apnea. The root of the problem may be stress or physiology. A doctor or dentist will have no sure way of knowing the cause of the patient’s symptoms without a definitive diagnostic test. If a patient begins to exhibit sleep disorder symptoms, they will likely be referred to a sleep clinic for an overnight sleep study call polysomnography.

Polysomnography is a non-invasive, painless procedure that is as easy on the patient as a night’s sleep, since that is just what it is. Through a referral from a doctor or dentist, the patient will consult with the doctors at the sleep center. There, an appointment will be set for the patient to come in overnight for the study itself. There are no drugs involved in polysomnography because they would interfere with normal sleeping patterns. Prior to the sleep study, the patient is instructed to stay away from any caffeine, alcohol, or drugs which he does not usually take. The patient should also keep a normal sleeping schedule in the days leading up to the polysomnography and to eschew heavy exercise the day of the study. Any of these factors could lead to a false diagnosis of sleep apnea or insomnia.

During the study, electrodes are placed on and around the face. These measure face and eye movement which can signal to the sleep doctor that the patient has entered a phase of sleep call Rapid Eye Movement (REM). Sometimes, especially if the referral comes from a dentist who suspects bruxism or tooth grinding, a sensor near the jaw muscles will also be placed. Other sensors will likely be placed on the chest to measure heart rate, and straps around the abdomen and chest will determine breathing rate. The patient’s brain waves will also be monitored to gauge the depth of sleep and the cycles through which the patient is going during the night’s polysomnography. Vocationally, if a patient complains of snoring, a microphone or video camera may be placed in the room. This gives the patient and doctor an eyeful and an earful of what the patient is doing in his sleep.

Through the results of polysomnography, the cause of sleeplessness can be narrowed down. Negative polysomnography results indicate that no sleep disorder is exhibited, but a positive result will lead to a diagnosis of a sleep disorder. If the suspect is sleep apnea, upper airway resistance syndrome (UARS) or sleep apnea snoring, the patient might have to undergo a second night of polysomnography to again measure breathing rate and oxygen flow levels. If the lung pressure stops during the night several times, central sleep apnea is the root, and the cause lies within the brain. If there is constant pressure from the lungs, but the patient is not getting enough or any oxygen, obstructive sleep apnea, with a physical blockage of the airway is likely the cause. A dentist, oral surgeon, or orthodontist can then be consulted for treatment. Should he be diagnosed with obstructive sleep apnea after the polysomnography, the patient must realize that either a sleep apnea oral appliance or obstructive sleep apnea surgery is likely. By seeking treatment from an experienced oral surgeon or dentist, success rates increase.

Remmers Sleep Recorder

SagaTech manufactures and markets the Remmers Sleep Recorder which records diagnostic indicators of sleep apnea, detects periodic leg movements in adults, and monitors the effectiveness of CPAP therapy. The Remmers Sleep Recorder is convenient and easy to use; the client attaches the necessary probes so that no technician or specialist need be present. A Windows™ based software package is included, providing data analysis on a personal computer and display of processed and unprocessed data. Test results are presented in a convenient, reliable, and inexpensive manner. The Remmers Sleep Recorder has been approved for sale in Canada and the USA.

The Remmers Sleep Recorder (Formerly SnoreSat™) records signals that are commonly used in diagnosing patients who are suspected of having sleep apnea. These signals are:

  • Blood oxygen saturation
  • Heart rate
  • Pulse amplitude
  • Nasal airflow (through nasal cannula pressure measurement)
  • Respiratory airflow (through pneumotachograph when CPAP is used)
  • Mask pressure (when CPAP is used)
  • Snoring sound
  • Body position
  • Respiratory movements

The Remmers Sleep Recorder also records electromyograms which can be used in the diagnosis of other sleep disorders.

  • Leg electromyograms for the diagnosis of periodic leg movements
  • Masseter electromyograms for the diagnosis of bruxism

Polysomnogram vs. Remmers Sleep Recorder

Adult sleep apnea, mainly OSA, is severely under-diagnosed, with an estimated 90-95% of all North American cases remaining undiagnosed . Potential patients typically face lengthy waiting periods to see a sleep physician and receive a diagnosis (1.5 to 4 years in Canada).

Polysomnogram (PSG) versus Remmers Sleep Recorder

Polysomnogram (PSG) is the gold standard for diagnosis of sleep apnea.  However, overnight PSG study is intrusive, costly, and requires the involvement of both a technician and an interpretative sleep specialist. For our purposes in evaluation of CPAP effectiveness, or to evaluate our dental appliances, we use a more convenient sleep apnea diagnostic device as an alternative to PSG. This device uses unattended monitoring in the home. The Remmers Sleep Recorder, manufactured by SagaTech, is capable of conveniently generating similar quality data in a home setting, without the involvement of a technician.

The Remmers Sleep Recorder Polysomnography (PSG)
Records the following diagnostic
indicators of sleep disordered breathing:

  • Blood oxygen saturation
  • Heart rate
  • Airflow via nasal cannula
  • Snoring sounds
  • Body position
  • Respiratory efforts
  • Two EMGs
PSG measures:

  • Breathing
  • Heart rate
  • Blood pressure
  • Electrocardiograms (ECG)
  • Electroencephalograms (EEG)
  • Chin muscle activity
  • Eye movement
  • Pulse oximetry
  • Respiratory effort
  • Airflow
  • Body position
  • Snoring
  • Extremity muscle activity