SESSION TITLE: Interventional Pulmonology Posters II
SESSION TYPE: Original Investigation Poster
PRESENTED ON: Wednesday, October 28, 2015 at 01:30 PM - 02:30 PM
PURPOSE: The aim of our study was to determine whether flexible cryobiopsy is a valid measure of airway smooth muscle changes after bronchial thermoplasty, compared to flexible forceps biopsy.
METHODS: We performed a single center, prospective study of five patients with severe asthma who underwent bronchial thermoplasty. On the first(pre-RLL bronchial thermoplasty) bronchoscopy, forceps and cryobiopsy samples were taken from the left lower lobe. Our primary study outcome was the presence of deep tissue structures in biopsy samples, using both flexible forceps biopsy and flexible cryobiopsy. This was assessed by obtaining endobronchial biopsies of airways of asthmatic patients. Specimens were stained with anti-alpha smooth actin antibody and picosirius red to identify smooth muscle area and collagen deposition from fibrosis, respectively. Morphometric data (airway wall area, smooth muscle area [as a percent of airway wall], and submucosal gland area[percent of airway wall]) were analyzed using ImageJ™ software.
RESULTS: There was no significant difference in bleeding or other complications between cryobiopsy and forceps biopsy procedures. Cryobiopsy samples trended to be larger than forceps biopsy samples(0.9mm2 vs 0.5mm2) with a significantly larger percentage of submucosal gland tissue visible(19.5% vs 0.7%). There also trended to be a larger percentage of smooth muscle area on the cryobiposy sample(26% vs 16%).
CONCLUSIONS: Cryobiopsy provided bronchial wall samples that were as large or larger than forceps biopsy. Both smooth muscle and submucosal gland tissue were available on cryobiopsy samples. Despite deeper samples obtained by cryobiopsy, there was no difference in bleeding complications. The current sample size is underpowered to show statistical significance and additional samples are required to draw further conclusions. However, this study supports the use of endobronchial cryobiopsy as a sampling modality to investigate airway wall histology. **This study has been funded by the AABIP to be presented at the AABIP Research Symposium during CHEST 2015**
CLINICAL IMPLICATIONS: This was the first study to compare cryobiopsy to forceps biopsy in the evaluation of airway histology in asthmatic patients. Endobronchial cryobiopsy is a useful tool in evaluating the benefit of endobronchial treatments for asthma, including bronchial thermoplasty.
DISCLOSURE: The following authors have nothing to disclose: Alex Chee, Austin Laing, Margaret Kelly, Alain Tremblay, Paul MacEachern, Richard Leigh
No Product/Research Disclosure Information