Extract
In recent years, tests of ventilation heterogeneity such as the multiple breath washout (MBW) have gained popularity as potentially sensitive measures of disease in the small airways [1]. The premise of a non-invasive test, such as the MBW, is that morphological alterations at differing lung depths can be sampled at the mouth via their effect on ventilation heterogeneity. MBW phase III slope derived indices of ventilation heterogeneity include the conductive slope index (Scond), a purely convection-dependent contribution generated in the conducting zone of the lungs, and the acinar slope index (Sacin), brought about by diffusion–convection mechanisms operating near acinar entrances in the respiratory zone [2, 3].
Abstract
By combining patient-specific CT-based airways with a clinically validated lung model, the proximal bronchioles were identified as the airways where structural abnormality can explain the increased convective ventilation heterogeneity in asthma patients http://bit.ly/2COT0Qh
Footnotes
Author contributions: B. Foy helped conceive the study, developed the computational model, performed simulations, analysed the data and co-wrote the manuscript. D. Kay supervised the creation of the computational model, provided a scientific critique of the data and edited the manuscript. S. Siddiqui and C. Brightling provided clinical interpretation of the data, oversaw CT segmentation and airway centreline generation and edited the manuscript. M. Paiva helped analyse the data, provided a scientific critique of the data, and edited the manuscript. S. Verbanck conceived the study, analysed the data, and co-wrote the manuscript.
Conflict of interest: B. Foy has nothing to disclose.
Conflict of interest: D. Kay has nothing to disclose.
Conflict of interest: S. Siddiqui has nothing to disclose.
Conflict of interest: C. Brightling reports grants and personal fees from GSK, AZ/MedImmune, Novartis, Chiesi, Pfizer, Vectura, Theravance, BI and Roche/Genetech, outside the submitted work.
Conflict of interest: M. Paiva has nothing to disclose.
Conflict of interest: S. Verbanck has nothing to disclose.
Support statement: This project was supported by the Fund for Scientific Research-Flanders (FWO-Vlaanderen, Belgium). Generation of the virtual lung structures was supported by an EU Framework 7 project grant (number 270194). Partially funded by Novartis UK. Funding information for this article has been deposited with the Crossref Funder Registry.
- Received July 8, 2019.
- Accepted November 12, 2019.
- Copyright ©ERS 2020
