Real-Time Assessment of Lung Structure and Function in Children and Young Adults With CF Using Electrical Impedance Tomography

Inclusion Criteria: Cohort 1: * Age 3-21 years * Male or female * Healthy subjects with no known or suspected chronic or temporary lung disease Cohort 2: * Age 3-21 years * Male or female * CF as diagnosed based on sweat chloride value(\>60 mmol/L) or two known disease causing mutations Cohort 3: * Age 3-21 years * Male or female * CF as diagnosed based on sweat chloride value (\>60 mmol/L) or two known disease causing mutations * Experiencing a protocol defined pulmonary exacerbation and being started on oral or intravenous antibiotics Exclusion Criteria: * Unwilling/refusal to sign consent * Known congenital heart disease, arrhythmia, or history of heart failure * Wearing a pacemaker or a metallic surgical implant in the chest * History of infection with Burkholderia cepacia * Developmental delays that could result in an inability to complete study procedures