PT  - JOURNAL ARTICLE
AU  - Laura L. Walkup
AU  - Kasiani Myers
AU  - Javier El-Bietar
AU  - Adam Nelson
AU  - Matthew M. Willmering
AU  - Michael Grimley
AU  - Stella M. Davies
AU  - Christopher Towe
AU  - Jason C. Woods
TI  - 129Xe MRI detects ventilation deficits in pediatric stem-cell transplant patients unable to perform spirometry
AID  - 10.1183/13993003.01779-2018
DP  - 2019 Jan 01
TA  - European Respiratory Journal
PG  - 1801779
4099  - http://erj.ersjournals.com/content/early/2019/02/13/13993003.01779-2018.short
4100  - http://erj.ersjournals.com/content/early/2019/02/13/13993003.01779-2018.full
AB  - Background Early detection of pulmonary morbidity following hematopoietic stem cell transplantation (HSCT) remains an important challenge for intervention, primarily due to the insensitivity of spirometry to early change, and in pediatrics, patient compliance provides additional challenges. Regional lung ventilation abnormalities in pediatric HSCT patients were quantified using hyperpolarized 129Xe magnetic resonance imaging (MRI) and compared to spirometry.Methods Medically-stable, pediatric allogeneic HSCT patients (n=23, ages 6–16) underwent an outpatient MRI where regional ventilation was quantified with a breath-hold of hyperpolarized 129Xe gas. Ventilation deficits, regions of the lung that poorly ventilate due to obstruction, were quantified as a ventilation defect percentage (VDP) and compared to FEV1, FEV1/FVC ratio, and FEF25–75% from spirometry using linear regression.Results The mean 129Xe VDP was 10.5%±9.4% (range 2.6–41.4%). 129Xe VDP correlated with FEV1, FEV1/FVC ratio, and FEF25–75% (p≤0.02 for all comparisons). Ventilation deficits were detected in patients with normal spirometry (i.e., FEV1>80%), supporting the sensitivity of 129Xe MRI to early obstruction reported in other pulmonary conditions. Seven patients (30%) could not perform spirometry, yet ventilation deficits were observed in 5 of these patients, detecting abnormalities that otherwise may have gone undetected and untreated until advanced.Conclusion Lung ventilation deficits were detected using hyperpolarized 129Xe gas MRI in asymptomatic pediatric HSCT patients and in a subgroup who were unable to perform reliable spirometry. 129Xe MRI provides a reliable imaging-based assessment of pulmonary involvement in this potentially difficult-to-diagnose pediatric population.FootnotesThis manuscript has recently been accepted for publication in the European Respiratory Journal. It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJ online. Please open or download the PDF to view this article.Conflict of interest: Dr. Walkup has nothing to disclose.Conflict of interest: Kasiani MyersConflict of interest: Javier El-BietarConflict of interest: Adam NelsonConflict of interest: Matthew M. WillmeringConflict of interest: Michael GrimleyConflict of interest: Stella M. DaviesConflict of interest: Christopher ToweConflict of interest: Jason C. Woods