It is very complicated for physicians to recognize the abnormalities of small airways non-invasively, tiny bronchioles primarily injured in COPD, which is around 1mm in inner diameter and is too small to be observed on CT imaging and not well-reflected by the tests of pulmonary function.

In the sight of study funded by NHLBI, international team of researchers done by Michigan medicine established the potential of non-invasive imaging biomarker for recognizing the damage of small airway in COPD.

One of the researcher in American Journal of Critical Care and Respiratory Medicine, reported that the potential of comparatively new technique, known as Parametric Response Mapping (PRM), for recognizing the abnormality of small airway in COPD. Craig Galban, Associate professor of radiology, and Brian Ross, Professor of Radiology & Biological chemistry at University of Michigan’s academic medical center, Michigan Medicine discovered that PRM is the non-invasive technique that measures the lung density at the time of exhalation and inhalation.

The team studied lung tissue from several patients with COPD following lung transplantation and those with strong donated tissue. Researchers then analyzed the samples back to CT scans taken in advance of surgery.

It was confirmed by the researchers that PRM has the capability to recognize the loss of small airway non-invasively, obstruction and narrowing. The technical feat need the partnership of huge, multi-disciplinary teams pulmonologists, radiologists, pathologists and thoracic surgeons in various locations in two countries, activated about the clock because of the irregular nature of transplant surgery.

MeiLan Han, lung specialist and professor of internal medicine at Michigan University claims that “Now we have confidence in our ability to identify airway disease when imaging COPD patients. PRM is already clinically available and used by University of Michigan clinical teams to assess patients with COPD. This is what we mean by bench to bedside medicine.”

The studies were carried on the patients with serious disease, in NHLBI funded study, COPDGene, defined PRM as the small airway abnormalities been detected on CT scans of patients with mild disease and assist in predicting the patients losing lung function. Han claimed that “We still need to validate the type of airway disease the PRM technique identifies in patients with milder disease. That type of lung tissue is more difficult to obtain, but we are working on techniques that would allow us to use smaller amounts of lung tissue to make such studies feasible.”

James Kiley, director of Division of Lung Diseases at National Heart, Blood and Lung Institute said that “These results illustrate the importance of developing non-invasive techniques for improving diagnostic capabilities and advancing new therapies needed to tackle this devastating disease”. “The refinement of this and similar approaches could also advance the study of COPD at its earliest stages of development”.