Pulmonary Function Tests for the Radiologist

Abstract

Pulmonary function tests (PFTs) provide important quantitative information about lung function and can be used to elucidate pathologic conditions responsible for respiratory symptoms, assess the severity and course of disease, and evaluate the patient for suitability and timing for lung transplantation. They are typically used in tandem with chest imaging, along with other ancillary data, to arrive at a specific diagnosis. PFTs may provide the radiologist with clues to the diagnosis and grading of a wide variety of pulmonary diseases. In this review, the authors discuss the clinical use of PFTs, their major components, and important measurements and graphical representations that are essential for understanding and interpreting the results. The key components of PFT panels-static lung volumes, dynamic lung function (spirometry), and diffusion capacity-are explained. The authors present a general algorithmic approach for problem solving, with recognition of common patterns of results (obstructive, restrictive, mixed, nonspecific, and normal). Pulmonary diseases from each of the major patterns and chest imaging are illustrated, and correlations between particular PFT results and disease severity and morphology at imaging are examined. Common pitfalls encountered during interpretation are also highlighted. A basic understanding of the mechanics of PFTs, characteristic patterns in important diseases, and correlation between lung function and imaging findings may assist the radiologist in diagnosis and follow-up of key pulmonary diseases and strengthen the radiologist's role as part of a multidisciplinary diagnostic team. Online supplemental material is available for this article. RSNA, 2017.

Prediction of Obstructive Lung Disease from Chest Radiographs via Deep Learning Trained on Pulmonary Function Data

“…All PFTs in the study are pre-bronchodilator values, as used in multiple COPD studies. [24][25][26] FEV1 is forced expiratory volume in 1 second. All 'FEV1ʹ values reported in this paper are "percent-predicted" (%predFEV1) as provided by the institution's PFT lab using the National Health and Nutrition Examination Survey (NHANESIII).…”

Pulmonary hyperclarity pattern in torax radiography: associated pathologies

“…It is considered a chronic disease that affects the respiratory tract, causing inflammation and changes in their normal structure. The diagnosis is clinical and through bronchodilator spirometry 8 .…”

Imaging Dynamic Expiration: Feasibility of MRI Spirometry Using Hyperpolarized Xenon Gas

“…The most clinically relevant spirometric measures of lung function are forced expiratory volume in 1 second (FEV 1 ), forced vital capacity (FVC; the maximum volume breathed out during a forced expiration), and the ratio of FEV 1 /FVC. These metrics are critical in categorizing disease phenotype in a patient with lung disease (1).…”

“…There are three main advantages of image-based spirometry. First, lung disease severity and subtype are often spatially heterogeneous, which cannot be identified with conventional clinical spirometry (1). Second, imaging-based spirometry could increase sensitivity for lung disease detection, as mild disease in a single lung segment or lobe may not be of sufficient magnitude to alter global tests of lung function but would be apparent on regional maps of lung function.…”