LATE-BREAKING ABSTRACT: Comparative studies on bronchuswall-thickness by histologic and computed tomographic measurements of porcine lungs

Abstract

Aims: Histologic slides are commonly used as template in the evaluation and development of medical imaging methods.Diseases like Asthma and COPD show characteristic changes in airway morphology and airway measurement by computed tomography is a promising diagnostic approach.However,shrinkage caused by fixation and histological processing is known in lung tissue.In this study,the thickness of bronchus walls in paraffin and frozen sections as well as in CT and MicroCT were compared. Methods: Airway measurements of swine lungs were performed after freezing in ventilated condition in liquid nitrogen by measuring the wall thickness of 7 bronchi via CT and MicroCT as well as in frozen and paraffin sections.Statistical analysis was performed using Wilcoxon test with significance at p Results: Airway measurement distinguished significantly between the groups.Bronchus wall thickness was smallest in frozen sections (median 0.71mm) followed by paraffin sections (median 0.75 mm),MicroCT (median 0.84 mm) and CT (median 1.69 mm).Statistical significance was given (p Conclusions: Striking differences were found in airway measurements performed in frozen and paraffin sections,MicroCT and CT.The diversity between bronchial wall size in paraffin and frozen sections is important regarding the comparison of radiologic data with histologic measurements in the further development of medical imaging.Further studies are necessary to assess the best representative histologic method for this purpose.Regarding radiology,CT has become a useful tool for airway imaging but MicroCT represented more adequate results of airway measurements in the present study and was superior compared to CT.