Comparison of histologic and computed tomographic measurements of pig lung bronchi
- Volker H. Schmitt1,2,9,
- Christine Schmitt3,9,10,
- David Hollemann4,
- Andreas Mamilos5,
- Willi Wagner6,7,
- Oliver Weinheimer6,7,11 and
- Christoph Brochhausen5,8,11⇑
- 1Department of Cardiology, University Medical Centre, Johannes Gutenberg University of Mainz, Mainz, Germany
- 2German Center for Cardiovascular Research (DZHK), Partner Site Rhine Main, Mainz, Germany
- 3Practice Dr. Wolf and Colleagues, Mainz, Germany
- 4Institute of Clinical and Molecular Pathology, State Hospital Horn, Horn, Austria
- 5REPAIR-lab, Institute of Pathology, University of Regensburg, Regensburg, Germany
- 6Department of Diagnostic and Interventional Radiology, University Hospital Heidelberg, Heidelberg, Germany
- 7Translational Lung Research Centre Heidelberg (TLRC), German Lung Research Centre (DZL), Heidelberg, Germany
- 8Central Biobank Regensburg, University Regensburg and University Hospital Regensburg, Regensburg, Germany
- 9Both authors contributed equally to this work and share first authorship
- 10This work contains parts of the MD thesis of C. Schmitt
- 11Both authors contributed equally to this work and share senior authorship
- Prof. Dr. Christoph Brochhausen, REPAIR-lab, Institute of Pathology, European Institute of Excellence for Tissue Engineering & Regenerative Medicine, University of Regensburg, Franz-Josef-Strauß Allee 11, 93053 Regensburg, Germany. E-mail: christoph.brochhausen{at}ukr.de
Abstract
Aim Light microscopy is used as template in the evaluation and further development of medical imaging methods. Tissue shrinkage caused by histological processing is known to influence lung tissue dimensions. In diagnostic of chronic obstructive pulmonary disease, computed tomography (CT) is widely used for automated airway measurement. We compared the bronchus wall thickness in histological and different image analysis methods.
Methods Airway measurements of pig lungs were performed after freezing under controlled inflation pressure in a liquid nitrogen bath. The wall thickness of seven bronchi was measured via MicroCT and CT using the integral based method (IBM) and the full-width-at-half-maximum method (FWHM) automatically and histologically on frozen and paraffin sections. Statistical analysis was performed using the Wilcoxon test, Pearson's correlation coefficient with a significance level at p<0.05, scatter plots and Bland Altman plots.
Results Bronchus wall thickness was smallest in frozen sections (median 0.71 mm) followed by paraffin sections (median 0.75 mm), MicroCT (median 0.84 mm) and CT measurements using IBM (median 0.68 mm) and FWHM (median 1.69 mm). Statistical significant differences were found among all tested groups (p<0.05) except for CT IBM and paraffin and frozen sections and MicroCT. High correlation was present between all parameters with statistical significance (p<0.05).
Conclusions Significant differences in airway measurement were found in the different analysing methods. The absolute measurements with CT IBM were closest to the histological results followed by MicroCT, whereas CT FWHM revealed a distinct divergence to the other groups.
Footnotes
This 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.
Conflict of interest: Dr. Schmitt has nothing to disclose.
Conflict of interest: Dr. Schmitt has nothing to disclose.
Conflict of interest: Dr. Hollemann has nothing to disclose.
Conflict of interest: Dr. Mamilos has nothing to disclose.
Conflict of interest: Dr. Wagner has nothing to disclose.
Conflict of interest: Dr. Weinheimer reports grants from DFG German Research Foundation, during the conduct of the study.
Conflict of interest: Dr. Brochhausen has nothing to disclose.
This is a PDF-only article. Please click on the PDF link above to read it.
- Received July 15, 2020.
- Accepted September 14, 2020.
- Copyright ©ERS 2020
This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial Licence 4.0.