Researchers develop test for disorder
Researchers at UH and The University of Texas Health Science Center at Houston have developed a method for detecting sleep apnea from a distance.
By using thermal infrared imaging (TIRI), researchers are capable of obtaining breathing waveforms and monitoring airflow. The TIRI captured thermal changes in the air that went through the patient’s nostrils.
‘We are now able to measure breathing function through thermal imaging,’ co-investigator and UH computer science professor Ioannis Pavlidis said in a press release Sunday.
This is the first research of its kind to be able to diagnose the disorder using noncontact technology.
Pavlidis and fellow researcher Jayasimha N. Murthy, assistant professor of medicine from the Division of Pulmonary Critical Care Sleep Medicine at UTHSC at Houston, collected data on 27 subjects at Memorial Hermann Hospital Sleep Disorders Center.
In the study, 14 participants had no history of a sleep disorder, and 13 had a history of sleep apnea. The researchers set the TIRI about 8 feet away from the patients. No physical probe was attached to the nostrils.
‘During a sleep study, a subject has an average of more than 20 sensors attached to the head and body,’ Murthy said in the release. ‘It’s a very complex procedure where many physiological parameters are simultaneously monitored to help in the diagnosis of sleep disorders.
‘However, these sensors can disturb sleep and contribute to the patient’s anxiety. With technologies such as thermal imaging and computational physiology, we hope to ‘unwire wired subjects’ during sleep studies.’
The virtual probe tracked the patients’ movements using computational algorithms – a sort of virtual tethering. Using TIRI proved to be as accurate as traditional methods and provided information that was not available before.
‘In contrast to the traditional one-dimensional methods, this new method is an imaging one, and thus multidimensional. We now can see how airflow is distributed locally throughout the extent of the nostril,’ Pavlidis said in the release. ‘We get not a single but multiple values for each nostril at every point in time, and this makes a lot of difference when it comes to appreciating subtle pathology.’
Although using TIRI keeps the nose and mouth area free of probes, it does not eliminate all contact sensors during a sleep study. Murthy and Pavlidis said that with more clinical trials, TIRI could change the way sleep apnea is diagnosed.
‘This is the first step in the development of this technology in airflow monitoring,’ Murthy said in the release. ‘I can foresee future applications for monitoring airflow in newborns and children, as well as situations such as respiratory isolation for contagious disease or traumatic injuries or the face where contact-free methods are the only option.’
Sleep apnea is a disorder that causes a person’s breathing to pause during sleep. This usually happens multiple times within an hour.
Sleepiness is the immediate consequence of the disorder, but long-term effects include hypertension, heart disease, stroke and diabetes.