Related Experiment Video
Updated: Jan 12, 2026

Monitoring Lung Function with Electrical Impedance Tomography in the Intensive Care Unit
Published on: September 6, 2024
Electrical impedance tomography reveals regional lung dysfunction in adults with preserved ratio impaired spirometry:
Junsong Zhang1, Shuoyao Qu1, Mingyi Kong2
1Department of Pulmonary and Critical Care Medicine, Xijing Hospital, Air Force Medical University, Xi'an, China.
Objective:
Preserved ratio impaired spirometry (PRISm) is a condition characterized by abnormal spirometry results despite a normal forced expiratory volume in the first second (FEV1)/forced vital capacity (FVC) ratio. We hypothesized that electrical impedance tomography (EIT) would detect regional decreases in lung function in subjects with PRISm. The study aimed to explore the regional lung function differences between subjects with preserved ratio impaired spirometry (PRISm) and healthy volunteers.
Methods:
In this observational study, subjects with respiratory symptoms visiting Xijing Hospital in May 2024 were rescreened for eligibility. Subjects meeting the PRISm criteria were included in the study. Electrical impedance tomography (EIT) and spirometry were conducted simultaneously. The same number of healthy subjects were studied, matching the gender, height, and weight in frequency. The regional lung function parameters were compared. A P-value of < 0.05 was considered statistically significant.
Results:
A total of 16 subjects with PRISm, and 16 healthy volunteers were included in the study and evaluated. Functional EIT images provided information about the location of the dysfunctional lung regions. All evaluated EIT-based parameters were worse in the subjects with PRISm. Statistically significant differences were found in the regional obstructive ratio (rOR) and the median of the regional time constant τmed (p < 0.05). EIT-based parameters did not correlate with spirometry-based parameters, except for spirometry FEV1/FVC, which showed correlations with rOR (r = -0.53, p = 0.03) and τmed (r = -0.62, p = 0.01) in subjects with PRISm. Both τmed and rOR values were quite low in healthy volunteers, whereas substantial changes were observed in subjects with PRISm.
Conclusion:
EIT-based regional lung function provides additional information to traditional spirometry, which visualizes and localizes regional lung function defects.
More Related Videos
Related Concept Videos
Pulmonary Function Tests
Pulmonary Function Tests are crucial diagnostic tools for assessing respiratory function, particularly in patients with chronic respiratory disorders. They comprehensively evaluate lung volumes, ventilatory function, breathing mechanics, diffusion, and gas exchange. These tests help diagnose pulmonary diseases and play a significant role in monitoring disease progression, evaluating disability, and assessing response to therapy.
PFTs involve using a spirometer, a...
Chronic Obstructive Pulmonary Disease-IV: Assessement and Diagnostic Studies
Medical History
Respiratory Volumes
Tidal Volume (TV) Tidal volume (TV) is the air inhaled or exhaled in a...
Physical Assessment of the Respiratory Tract II: Inspection
Chest Configuration
The chest configuration...
Radiological Investigation II: MRI and Ventilation Perfusion Scan
Magnetic Resonance Imaging (MRI) and Ventilation Perfusion Scans are two radiological investigations that offer detailed diagnostic images of the body, particularly lung structures.
MRI
MRI uses magnetic fields and radiofrequency signals to distinguish between normal and abnormal tissues. This technology provides a more detailed diagnostic image than CT scans, enabling it to characterize pulmonary nodules, stage bronchogenic carcinoma, and evaluate inflammatory activity in...

