Mapping Your Lungs

COPD gets a closer look through new technology

(RxWiki News) A few years ago, starting on a road trip meant packing a folding paper map. Now, 3-D satellite images are at our fingertips on smartphones to plan the route and show what’s up ahead. What if we could also map a path through our lungs? 

A new study tested a technique that could help doctors get a similarly detailed view of their patients’ lungs.

This might improve their ability to diagnose and treat chronic obstructive pulmonary disease (COPD).

"See your doctor for COPD questions."

Craig J Galbán, PhD, of the Department of Radiology and Center for Molecular Imaging at the University of Michigan at Ann Arbor, and colleagues led the study to find out if a new scanning technology could help individualize treatments for COPD patients.

Traditionally, doctors use two-dimensional computed tomography (CT) scans to look at their patients’ lungs.

The new technique used in the study is called parametric response mapping (PRM). It creates a three-dimensional “map” of the lungs by putting multiple CT scans together at the same time.

For this study, researchers obtained CT scans from 194 COPD patients that had been enrolled in a much larger research initiative called the COPDGene study.

The participants they selected had different levels of COPD from mild to severe, including emphysema.

Using the CT scans, researchers used the PRM analysis with each patient. PRM assigned one of three colors to small areas within the lungs, called voxels, to show their level of health.

Green meant healthy, yellow meant a reduced ability to push air out of the small sacs and red meant severely reduced ability.

They then compared their PRM readings with physical exam results measuring patients’ lung capacity.

The study found that PRM improved the doctors' ability to tell the difference between early-stage damage to the small airways of the lungs and more severe damage, known as emphysema. So the PRM also helped them differentiate between different types of COPD.

The PRM diagnoses also matched with how patients performed on the lung tests that measured their breathing ability.

Researchers also found they could use the PRM technique to learn more about how COPD affected the lungs over time and what the best treatment would be for those changes in each individual.

"We believe this offers a new path to more precise diagnosis and treatment planning and a useful tool for precisely assessing the impact of new medications and other treatments," said co-author Brian Ross, PhD, a radiology and biological chemistry professor at UM.

Imbio, a company associated with the University of Michigan, has received a patent for the new technology.

When contacted, Imbio reported they hope to have a version available to researchers this year and are working towards FDA approval for patient use by the end of 2013. Imbio doesn’t yet report the anticipated cost.

The study was published online on October 7 in the journal Nature Medicine.

The research was funded by the National Institutes of Health, including the National Cancer Institute, the National Heart, Lung and Blood Institute and the National Institute of Biomedical Imaging and Bioengineering.

Three of the authors have a financial interest in the underlying technology described in this study.

Review Date: 
October 24, 2012