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Updated: May 21, 2026
Monitoring Lung Function with Electrical Impedance Tomography in the Intensive Care Unit
Published on: September 6, 2024
Regional ventilation in cystic fibrosis measured by electrical impedance tomography
Zhanqi Zhao1, Rainald Fischer, Inéz Frerichs
1Department of Biomedical Engineering, Furtwangen University, Jakob-Kienzle-Strasse 17, 78054, Villingen-Schwenningen, Germany. zhanqi.zhao@hs-furtwangen.de
Background:
The feasibility of electrical impedance tomography (EIT) as an alternative examination tool in cystic fibrosis (CF) was examined.
Methods:
14 CF patients and 14 healthy volunteers were studied. Spirometry and EIT measurements were performed simultaneously. The global inhomogeneity (GI) index was applied to assess the degree of ventilation homogeneity at different levels of maximum inspiratory volume. Ratios of maximum expiratory flow at 25% and 75% of vital capacity (MEF(25)/MEF(75)) were calculated for both global lung and regional areas in EIT images.
Results:
Significant differences among GI values at various lung volumes were found in CF patients (P<0.01) but not in healthy subjects. Global MEF(25)/MEF(75) measured with spirometry and with EIT were highly correlated for all subjects (r(2)=0.69, P<0.01). Significant difference in global MEF(25)/MEF(75) was found between CF patients and healthy volunteers with both spirometer (CF: 0.15±0.09; healthy: 0.46±0.15; P<0.001) and EIT (CF: 0.14±0.09; healthy: 0.42±0.08; P<0.001). Regional airway obstruction was identified in the MEF(25)/MEF(75) maps in CF patients.
Conclusions:
Compared to the global parameters provided by spirometry, EIT is able to deliver both global and regional information to assess the airway obstruction in CF patients.
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