RT Journal Article
SR Electronic
T1 Evaluation of spirometry gated CT scan to measure lung volumes in emphysema patients
JF ERJ Open Research
JO erjor
FD European Respiratory Society
SP 00492-2021
DO 10.1183/23120541.00492-2021
A1 Jens T Bakker
A1 Karin Klooster
A1 Jan Bouwman
A1 Gert Jan Pelgrim
A1 Rozemarijn Vliegenthart
A1 Dirk-Jan Slebos
YR 2021
UL http://openres.ersjournals.com/content/early/2021/12/02/23120541.00492-2021.abstract
AB Introduction In emphysema patients, being evaluated for bronchoscopic lung volume reduction (BLVR), accurate measurement of lung volumes is important. Total Lung Capacity (TLC) and Residual Volume (RV) are commonly measured by body-plethysmography, but can also be derived from chest computed tomography (CT). Spirometry-gated CT scanning potentially improves the agreement of CT and body-plethysmography.Objective To compare lung volumes derived from spirometry-gated CT and “breath-hold-coached” CT to the reference standard: body-plethysmography.Methods In this single centre retrospective cohort study, emphysema patients, evaluated for BLVR, underwent body-plethysmography, inspiration (TLC) and expiration (RV) CT-scan with spirometer guidance (“gated group”) or with breath-hold-coaching (“non-gated group”). Quantitative analysis was used to calculate lung volumes from the CT.Results We included 200 patients (age 62±8 years, FEV1 29.2±8.7%, TLC 7.50±1.46 L, RV 4.54±1.07 L). The mean CT-derived TLC was 280(±340)ml lower compared to body-plethysmography in the gated group (n=100), and 590(±430)ml lower for the non-gated group (n=100) (both p<0.001). The mean CT-derived RV was 300(±470)ml higher in the gated group and 700(±720)ml higher in the non-gated group (both p<0.001). Pearson correlation factors were 0.947 for TLC gated, 0.917 for TLC non-gated, 0.823 for RV gated, 0.693 for RV non-gated, 0.539 for %RV/TLC gated and 0.204 for %RV/TLC non-gated. The differences between the gated and non-gated CT results for TLC and RV were significant for all measurements (p<0.001).Conclusion In severe COPD patients with emphysema, CT-derived lung volumes are strongly correlated to body-plethysmography lung volumes, and especially for RV, more accurate when using spirometry-gating.FootnotesThis manuscript has recently been accepted for publication in the ERJ Open Research. 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 ERJOR online. Please open or download the PDF to view this article.