Electrical impedance tomography reveals ventilation and perfusion heterogeneity in infants with bronchopulmonary dysplasia

Abstract

Objective: Preterm infants have pulmonary ventilation and perfusion abnormalities, yet few imaging modalities can inform clinicians about this ventilation/perfusion (V/Q) relationship. Electrical impedance tomography (EIT) is an imaging technique with V/Q imaging capabilities that has not been well described in infants with BPD.

Study design: EIT was performed every 4 weeks in preterm infants for a maximum of 5 visits per infant. Term infants with healthy lungs had one EIT imaging visit as controls.

Results: Data were collected from a total of 51 EIT visits. Novel V/Q maps were generated from each visit. Ventilation heterogeneity (measured by the global inhomogeneity index) and V/Q heterogeneity (measured by coefficient of variation of V/Q maps) were significantly higher in preterm infants at the visit closest to 36 weeks post-menstrual age than controls (p = 0.002 and p = 0.039, respectively).

Conclusions: Pulmonary ventilation, perfusion, and V/Q relationship can be quantified by EIT, and may be indicators of chronic lung disease.