Most patients think in terms of dollar signs and insurance coverage if their healthcare provider mentions an MRI.
But for those who suffer from chronic obstructive pulmonary disease (COPD), a magnetic resonance imaging test could be a gift from medical heaven.
A study released today in the journal Radiology makes a strong case for the use of medical imaging of lung fields and states that MRI images could ultimately reduce costs and improve treatment for COPD.
The diagnosis of COPD usually requires pulmonary function tests that involve exhaling forcefully into a machine to come up with a measure known as the forced expiratory volume in one second (FEV1).
Researcher Grace Parraga, Ph.D., of the Robarts Research Institute in London, Ontario, Canada, acknowledges that FEV1 is “a useful measurement,” but she says it has significant limitations.
“It doesn’t tell you where the problem is in the lungs. Is it in the airways? In the air sacs? Or what part of the lung is affected: Top? Bottom? Which lobes?” she said.
Knowing this information can help providers understand why a patient is experiencing certain symptoms. That, in turn, can help shape a patient’s overall treatment plan and possibly reduce their need for emergency or unplanned visits to the hospital.
“When you can see the disease and measure it, this allows you to better manage and treat it,” Parraga said.
COPD Is a Debilitating, Deadly Disease
COPD is most common in smokers or those exposed to secondhand smoke or occupational pollutants.
About 65 million people suffer from COPD worldwide, with an estimated 45 million people in North America. It’s the fourth-leading cause of death in the United States, resulting in 126,000 deaths each year.
The disorder is a combination of chronic bronchitis, which causes excessive mucus buildup in the airways, and emphysema, which causes damage and destruction of the tiny air sacs of the lungs known as alveoli.
Even for those with mild or moderate forms of COPD, daily tasks such as walking up stairs or across a parking lot can cause severe shortness of breath and fatigue.
A Wide Variety of Effects
Researchers in the recent study wanted to make sense of why some patients classified as mild have severe limitations while others experience few problems.
“Our study was driven by our desire to better understand why some patients have very bad symptoms and cannot do relatively simple day-to-day tasks, while others with the same FEV1 don’t seem to be affected as much,” said Parraga. “In so–called mild disease where FEV1 is only modestly abnormal, the range of patient symptoms and effects is large.”
The study used MRI and CT scans to see abnormalities in the lungs of 116 patients with COPD.
Patients inhaled inert helium gas that is visible on MRI, allowing researchers to see detailed images of the anatomical structure and function of the lungs.
Both MRI and CT images helped to explain patients’ symptoms. But the MRIs found specifically that emphysema — the destroyed or damaged air sacs — correlated with exercise limitations.
“We can explain different symptoms of breathlessness and inability to do day-to-day exercise by the presence of emphysema — and this is an important result,” Parraga said. “Knowing the exact source of patient symptoms will help guide therapy decisions.”
COPD Is a Costly Disease
COPD patients comprise about one third of all clinic appointments and emergency department visits.
The initial cost of medical imaging is two to three times greater than the traditional FEV1 diagnostic tool, which takes about 40 minutes longer to perform.
But Parraga thinks that MRI imaging would ultimately save the healthcare industry and patients money and time because poorly treated COPD can significantly tax the healthcare system.
“[COPD patients] use more resources, more often, over longer periods of time,” she said. “This is an enormous cost that stems from the fact that acute and long-term COPD effects are not adequately treated.”
Imaging could guide providers to step up treatment from the mild to moderate or moderate to severe category. Adding an inhaled steroid treatment or prescribing low-flow oxygen could accompany the traditional bronchodilating inhalers used in mild forms of the disorder. With emphysema, patients may also consider surgery to remove parts of the lung that don’t function.
For patients with severe day-to-day symptoms, Parraga says, “It may be less expensive to undergo tests that help explain the source of these symptoms, so that the right treatment can be prescribed, minimizing repeated visits to patient care providers and use of finite healthcare system resources.”