Abstract
Introduction: Airway diseases are characterized by structural airway remodeling, including extracellular matrix (ECM) changes. Although a key feature, no diagnostic test currently assesses airway remodeling other than invasive airway biopsies. Real-time optical coherence tomography (OCT) generates infrared-based cross-sectional images of airway segments. Previously we reported that OCT identifies and quantifies airway wall layers. We hypothesized that OCT is able to detect collagen deposition areas within the airway wall ECM.
Methods: In 5 lobectomy specimens 13 airways were dissected, marked with needles for matching histology and imaged by OCT. Sections were stained for total collagen (TC; pico sirius red) and collagen type I A1 (CA1; antibody). Color deconvolution was used to quantify TC or CA1 area (ImageJ). OCT images were segmented by light scattering intensity after thresholding, attenuation and roll-off correction. Areas were measured in mm2 and defined as % of the airway wall.
Results: 23 airway OCT images with matched histology sections stained for TC and CA1 were analyzed (Fig. 1A-F). OCT area showed a significant correlation with TC area (r=0.52, p=0.01) and a non-significant correlation with CA1 area (r=0.31; p=0.12).
Conclusion: OCT scattering area appears to correspond to collagen within the airway wall. Therefore, OCT may represent an imaging technique of choice to assess airway remodeling.
Footnotes
Cite this article as: European Respiratory Journal 2019; 54: Suppl. 63, PA3169.
This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).
- Copyright ©the authors 2019
