Infrared imaging for sleep apnea diagnosis shows promise

October 23, 2007

(Chicago, IL, October 23, 2007) -- Sleep apnea is commonly diagnosed by way of measuring airflow by nasal pressure, temperature, and/or carbon dioxide, through sensors placed in the nose. However, this method is uncomfortable to some and can potentially disturb sleep. But new research, presented at CHEST 2007, the 73rd annual international scientific assembly of the American College of Chest Physicians (ACCP), shows that remote infrared imaging can monitor airflow and accurately detect abnormalities during sleep, without ever coming in contact with the patient. The study indicates that the new method is ideal because it is portable and can monitor sleep in a natural environment.

"Polysomnography is a diagnostic test, which establishes the presence or absence of sleep disorders. But standard methods have the potential to significantly disturb a patient's sleep pattern, so what we see in the lab may not be a true representation of the patient's sleep habits," said lead study author Jayasimha Murthy, MD, Assistant Professor of Medicine, University of Texas Health Science Center at Houston, TX. "However, remote infrared imaging is a noncontact method, so there is minimal interference with the patient. In fact, this system can be designed to where the patient isn't even aware that monitoring is taking place."

In the first study of its kind, Dr. Murthy and his colleagues from the University of Texas Health Science Center at Houston, the University of Houston, and Memorial Hermann Sleep Disorders Center in Houston, TX, evaluated the efficacy of remote infrared imaging (IR-I) in 13 men and women without known sleep apnea. Researchers recorded the heat signals expired from patients' nostrils or mouth using an infrared camera during 1 hour of polysomnography. To minimize any bias, airflow channels were recorded and analyzed separately. Results were then compared with those obtained through the conventional methods of sleep apnea diagnosis, including nasal pressure, nasal-oral thermistors, and capnography.

"The underlying principle of monitoring the relative changes in airflow based on the changing of the infrared heat signal is similar to that of the traditional thermistor," Dr. Murthy explained. "However, the biggest difference is that the thermistor is placed in the subject's nostril while the infrared camera is placed 6 to 8 feet from the patient's head. Also, this method allows us to have recorded data, so we can go back and extract the airflow data after the completion of the study, which we can't do with conventional sensors."

Upon completion, results showed that IR-I detected 20 sleep-disordered breathing events, compared with 22 events detected by the nasal-oral thermistor, and 19 events detected by nasal pressure. Given the outcome, researchers suggest that IR-I was in near-perfect agreement with conventional methods and that it represents a noncontact alternative to standard nasal-oral thermistors. Though Dr. Murthy acknowledges that this study represents a preliminary stage of testing, he is optimistic about the future of infrared imaging for sleep disorder diagnosis.

"The results from this study will greatly impact the development of this technology," he said. "While implementation of this technology for clinical studies is still far away, these early results are encouraging enough for us to pursue this further."

"Sleep apnea is a debilitating condition that affects millions of Americans and can lead to other, life-threatening illnesses," said Alvin V. Thomas, Jr., MD, FCCP, President of the American College of Chest Physicians. "It is important for physicians and researchers to continue to explore new diagnostic tools in order to detect and treat this sleep disorder at the earliest possible stage."
-end-
CHEST 2007 is the 73rd annual international scientific assembly of the American College of Chest Physicians, held October 20-25 in Chicago, IL. ACCP represents 17,000 members who provide patient care in the areas of pulmonary, critical care, and sleep medicine in the United States and throughout the world. The ACCP's mission is to promote the prevention and treatment of diseases of the chest through leadership, education, research, and communication. For more information about the ACCP, please visit the ACCP Web site at www.chestnet.org.

American College of Chest Physicians

Related Sleep Apnea Articles from Brightsurf:

Sleep apnea may be risk factor for COVID-19
The question of sleep apnea as the risk factor for COVID-19 arose in a study conducted by the Turku University Hospital and the University of Turku on patients of the first wave of the pandemic.

Untreated sleep apnea is associated with flu hospitalization
As we approach flu season, adults with obstructive sleep apnea may want to take extra precautions.

Losing tongue fat improves sleep apnea
Using magnetic resonance imaging (MRI) to measure the effect of weight loss on the upper airway in obese patients, researchers found that reducing tongue fat is a primary factor in lessening the severity of OSA.

More cancer cases among women with sleep apnea
Women with severe sleep apnea appear to be at an elevated risk of getting cancer, a study shows.

New evidence on the association of shortened sleep time and obstructive sleep apnea with sleepiness and cardiometabolic risk factors
A new study in the journal CHEST® may change the way we think about sleep disorders.

Synthetic cannabis-like drug reduces sleep apnea
A synthetic cannabis-like drug in a pill reduced apnea and daytime sleepiness in the first large multi-site study of a drug for apnea.

Inflammation may precede sleep apnea, could be treatment target
Inflammation is traditionally thought of as a symptom of sleep apnea, but it might actually precede the disorder, potentially opening the door for new ways to treat and predict sleep apnea, according to researchers.

Concerns that sleep apnea could impact healthspan
The number of people with obstructive sleep apnea has steadily increased over the past two decades.

Sleep apnea and insomnia combination linked with depression
A new study found that men with sleep apnea and insomnia have a higher prevalence and severity of depressive symptoms than men with sleep apnea or insomnia alone.

Anti-nausea drug could help treat sleep apnea
An old pharmaceutical product may be a new treatment for obstructive sleep apnea, according to new research presented today by University of Illinois at Chicago and Northwestern University scientists at the SLEEP 2017 annual meeting in Boston.

Read More: Sleep Apnea News and Sleep Apnea Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.