PT  - JOURNAL ARTICLE
AU  - John Kenworthy
AU  - Helen Marshall
AU  - Steven Thomas
AU  - Juan Parra-Robles
AU  - Xiaojun Xu
AU  - General Leung
AU  - Salman Siddiqui
AU  - Christopher Brightling
AU  - James M. Wild
TI  - Quantifying peripheral and central lung response to bronchodilator in asthma with hyperpolarised gas MRI
DP  - 2013 Sep 01
TA  - European Respiratory Journal
PG  - P2267
VI  - 42
IP  - Suppl 57
4099  - http://erj.ersjournals.com/content/42/Suppl_57/P2267.short
4100  - http://erj.ersjournals.com/content/42/Suppl_57/P2267.full
SO  - Eur Respir J2013 Sep 01; 42
AB  - Background: Hyperpolarised gas MRI is sensitive to regional ventilation changes, which can be quantified as a percentage of total lung volume.Objective: To quantify lung ventilation response to bronchodilator in patients with asthma on a global and regional basis.Methodology: 24 asthmatic patients were scanned using synchronous hyperpolarised 3He and 1H lung MRI before and after bronchodilator use. 1H images were used to measure lung volume (LV) using a seed growing algorithm (Slicer 3D, Harvard). Ventilation volumes (VV) were calculated using manual thresholding on 3He images. Whole lung percentage ventilated volumes (%VV) were calculated by VV÷LV. The peel (peripheral 1/3 of the lung) and core (inner 2/3 of the lung) %VV were automatically segmented.Results: Significant increase in %VV was measured (Wilcoxon rank) following bronchodilator when calculated globally (p=0.001) and for core (p=0.007) and peel (p=0.004). Ventilation improvement was greater in the peel than the core (Parametric t-test p=0.024).Conclusions: Hyperpolarised gas MRI measured increased ventilation following bronchodilator in a cohort of 24 asthmatics, with a greater response in the lung periphery than the central core suggesting a biasing towards small airway involvement both in the underlying asthma pathology and its response to bronchodilator.Research funded by Novartis and EU FP7 programmes: Airprom and PInet.