Imagine airways in people with breathing problems

Critical to this procedure is the ability of doctors to measure the extent of stenosis -- the diameter and length of the narrowed section of airway. Making this measurement accurately helps doctors choose the most appropriately sized stent for each person.

The current clinical practice for imaging the airway combines CT scans with "video endoscopy" images, which involves inserting a tiny video camera into the airways inside the lungs. Now a group of engineers, clinicians and medical researchers at the University of Western Australia and Sir Charles Gairdner Hospital have developed a new optical technique to help better guide treatment decisions. Their technique, called anatomical optical coherence tomography (aOCT), can accurately measure the shape, diameter and length of the airways inside the lungs, even as they expand and contract during breathing.

This new technique is an improvement over video endoscopy, says Robert McLaughlin, who was part of the research team. Video images captured with endoscopy are two-dimensional, which makes it difficult for doctors to accurately estimate the true three-dimensional size and shape of the narrowing airways. Imaging the airway with aOCT, on the other hand, relies on inserting a probe into the airway that emits a very safe, low-power light. The size of the airway can then be measured by detecting the reflected light.

The technology is being tested to see if it can help doctors diagnose and treat people with breathing disorders, says McLaughlin. Other current clinical studies are testing whether aOCT can detect airway changes in people with asthma and chronic obstructive pulmonary disease. According to McLaughlin, this technology can also be used during sleep in patients with sleep apnea, to better understand why the upper airway (throat) collapses and narrows in these individuals.

The new ISP technology enables those reading the paper to see first-hand how aOCT works in airway imaging. -Optical Society of America