Clinical correlates of lung ventilation defects in asthmatic children

J Allergy Clin Immunol. 2016 Mar;137(3):789-96.e7. doi: 10.1016/j.jaci.2015.08.045. Epub 2015 Oct 29.


Background: Lung ventilation defects identified by using hyperpolarized 3-helium gas ((3)He) lung magnetic resonance imaging (MRI) are prevalent in asthmatic patients, but the clinical importance of ventilation defects is poorly understood.

Objectives: We sought to correlate the lung defect volume quantified by using (3)He MRI with clinical features in children with mild and severe asthma.

Methods: Thirty-one children with asthma (median age, 10 years; age range, 3-17 years) underwent detailed characterization and (3)He lung MRI. Quantification of the (3)He signal defined ventilation defect and hypoventilated, ventilated, and well-ventilated volumes.

Results: The ventilation defect to total lung volume fraction ranged from 0.1% to 11.6%. Children with ventilation defect percentages in the upper tercile were more likely to have severe asthma than children in the lower terciles (P = .005). The ventilation defect percentage correlated (P < .05 for all) positively with the inhaled corticosteroid dose, total number of controller medications, and total blood eosinophil counts and negatively with the Asthma Control Test score, FEV1 (percent predicted), FEV1/forced vital capacity ratio (percent predicted), and forced expiratory flow rate from 25% to 75% of expired volume (percent predicted).

Conclusion: The lung defect volume percentage measured by using (3)He MRI correlates with several clinical features of asthma, including severity, symptom score, medication requirement, airway physiology, and atopic markers.

Keywords: (3)He magnetic resonance imaging; Hyperpolarized; childhood asthma; severe asthma; ventilation defects; ventilation heterogeneity.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Asthma / diagnosis*
  • Asthma / physiopathology*
  • Child
  • Child, Preschool
  • Female
  • Forced Expiratory Volume
  • Helium
  • Humans
  • Immunoglobulin E / immunology
  • Isotopes
  • Magnetic Resonance Imaging / methods
  • Male
  • Pulmonary Ventilation*
  • Risk Factors
  • Severity of Illness Index
  • Vital Capacity


  • Isotopes
  • Helium
  • Immunoglobulin E