by Pulmonary Function Tests Evaluate Respiratory Disease Testing
Pulmonary function tests, also known as PFTs or lung function tests, are noninvasive procedures that evaluate how well the lungs take in and release air. There are several types of PFTs that can help detect and assess conditions affecting the lungs such as asthma, chronic obstructive pulmonary disease (COPD), and interstitial lung disease.
Spirometry is one of the most common PFTs performed. During spirometry, the person breathes into a mouthpiece or nozzle connected to a machine that measures airflow. Key measurements include forced vital capacity (FVC), which is the total amount of air that can be forcibly exhaled after taking the deepest breath possible, and forced expiratory volume in one second (FEV1), which is the amount of air that can be forcibly blown out in the first second of exhalation. The FEV1/FVC ratio can help diagnose obstructive lung diseases like asthma or COPD where airflow is blocked.
Another test is lung volume measurement, which assesses residual volume (RV), functional residual capacity (FRC), and total lung capacity (TLC). RV is the amount of air left in the lungs after a maximum exhalation. Respiratory Disease Testing FRC is the amount of air left in the lungs after a normal relaxed exhalation. TLC is the total amount of air the lungs can hold. Abnormal results may suggest restrictive lung diseases that limit the lungs’ ability to expand fully.
Diffusing capacity testing, also called DLCO or transfer factor testing, measures how well oxygen passes from the lungs into the blood. It can help diagnose interstitial lung diseases affecting the lung tissue.
Chest Imaging Provides Structural Views of the Lungs
Chest X-rays and computed tomography (CT) scans provide images of the lungs’ internal structure to evaluate abnormalities. A standard chest X-ray may reveal signs of conditions like pneumonia, COPD, and lung cancer.
CT scanning uses X-rays combined with computer technology to create cross-sectional images or slices of the chest. CT scanning is more sensitive than chest X-rays and allows doctors to see the lungs in great detail. It is better able to detect small changes in the lungs that may indicate interstitial lung diseases or early-stage cancers. Respiratory Disease Testing CT scanning is frequently used to follow lung disease progression over time or after treatment interventions.
High-resolution CT (HRCT) is an advanced form of CT scanning that provides even clearer visualizations of the lungs down to the size of small airways and blood vessels. HRCT has become a standard tool for diagnosing sporadic and occupational diffuse parenchymal lung diseases. The specific patterns of scarring, nodules, or airspace enlargement seen on HRCT can help characterize different forms of interstitial lung disease.
Biopsy Provides Tissue Samples for Respiratory Disease Testing
When imaging or pulmonary function tests do not provide a clear diagnosis, a biopsy may be needed to analyze lung tissue samples. Bronchoscopy allows doctors to insert a thin, lighted flexible tube (bronchoscope) through the mouth or nose to directly examine the airways. During bronchoscopy, small tissue samples (biopsy) can be collected using biopsy forceps.
A bronchoscopy with biopsy is often used to diagnose lung cancer, infections, and diffuse parenchymal lung diseases. Examining tissue under a microscope can reveal cell changes, growths, inflammation, and fibrosis that provide important diagnostic clues.
For inaccessible areas of the lungs, a needle biopsy or video-assisted thoracoscopic surgery (VATS) biopsy may be recommended. In a CT-guided needle biopsy, a radiologist uses CT imaging to precisely guide a hollow needle into the area of interest to extract a sample. VATS involves making small incisions in the chest wall and inserting tubes with miniaturized cameras to localize abnormalities and retrieve biopsy tissue or lavage samples for analysis.
Nuclear Scan Tests Lung Function
In addition to anatomical imaging, nuclear scans use radioactive substances or tracers to assess lung function at the molecular level. Ventilation/perfusion (V/Q) scanning involves inhaling a radioactive gas that tracks airflow in the lungs, followed by an IV injection of a radioactive tracer to track blood flow. This dual analysis can identify clots in the pulmonary arteries or other defects impacting ventilation versus perfusion. Abnormal V/Q scan results suggest conditions such as pulmonary embolism.
A lung scintigraphy or lung scan uses Technetium-99m to trace a radioactive aerosol inhaled through a nebulizer mask. The aerosol deposits in areas of abnormal ventilation, and its pulmonary distribution pattern on imaging may point to obstructive airway diseases versus interstitial lung diseases such as pulmonary fibrosis. Lung scintigraphy is not routinely performed nowadays due to the advent of more sensitive diagnostic modalities.
Nuclear medicine approaches offer an alternative functional view of lung health compared to anatomical imaging. They can provide unique insights to assist diagnosis in certain difficult clinical contexts. As testing continues advancing, multi-disciplinary data combining functional, structural, and tissue-based evaluations delivers the most comprehensive perspective for uncovering respiratory diseases.
*Note:
1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it
About Author - Money Singh
Money Singh is a seasoned content writer with over four years of experience in the market research sector. Her expertise spans various industries, including food and beverages, biotechnology, chemicals and materials, defense and aerospace, consumer goods, etc. LinkedIn Profile
