Using electrical impedance tomography to characterize lung impairment of children with primary ciliary dyskinesia: A pilot cross-sectional study.

Abstract

In children with primary ciliary dyskinesia (PCD), measures more sensitive than spirometry are needed to characterize underlying pulmonary impairment. Electrical impedance tomography (EIT) is a promising noninvasive method for monitoring the distribution of lung ventilation, and it does not require patient collaboration. We aimed to provide an assessment of the feasibility and clinical usefulness of EIT in characterizing lung impairment in children with PCD, compared to spirometry and multiple breath nitrogen washout (MBWN2 ) test. Children and adolescents with PCD underwent MBWN2 test as first respiratory assessment, followed by EIT monitoring and spirometry during outpatient follow-up. We included 12 out of 16 individuals regularly followed at our clinic. A total of 41.7% (5/12) showed abnormalforced expiratory volume in 1 s (FEV1 ), whereas 11/12 (91.7%) had abnormal ventilation inhomogeneity measured with MBWN2 test. Using EIT, the global inhomogeneity (GITOT ) index showed moderate to strong correlation with FEV1 (ρ = -0.55, 95% confidence interval [CI]: -0.87 to 0.02) and ranged from 37 to 44, with the highest inhomogeneity detected in the dorsal right quadrant. GITOT was moderately correlated with RV/TLC %predicted (ρ = 0.38, 95%CI: -0.17 to 0.74), while we detected a weak correlation between GITOT and lung clearance index(ρ = 0.29, 95%CI: -0.45 to 0.82). EIT appears promising as a noninvasive technique to characterize ventilation distribution in children with PCD, thus providing a complementary assessment to static and dynamic lung function measures of PCD disease.