Balloon dilatation for bronchoscope delivery: first-in-human trial of a novel technique for peripheral lung field access

Q: What problem does the BDBD technique address in bronchoscopy?

It addresses bronchoscopic limitations in reaching peripheral pulmonary lesions by dilating the bronchial pathway, which helps advance the bronchoscope to the peripheral lung region for biopsy.

Q: Who was included in the study and how were bronchoscopy procedures performed?

Patients with bronchus sign-positive PPLs measuring under 20 mm were included. Bronchoscopy used ultrathin or thin bronchoscopes under conscious sedation, and BDBD was applied when the scope could not advance further.

Q: What diagnostic performance and safety results were reported?

Among 22 patients, 18 were diagnosed with cancer after BDBD-assisted bronchoscopy. BDBD enabled advancement in all 18 without serious complications, provided direct biopsy site visualisation in 17, and yielded a reported malignancy diagnostic sensitivity of 77.8% (14/18).

Q: What do the authors conclude and what is the next step?

In this small observational study, BDBD appeared promising for improving diagnostic sensitivity for small PPLs. Further validation is required in larger cohorts.

Sep 23, 2026

Uploaded by hdkawk

Bronchoscopic access limits biopsy sensitivity for peripheral pulmonary lesions (PPLs), particularly small lesions. A balloon dilatation for bronchoscope delivery (BDBD) technique was developed to dilate bronchial pathways and advance an ultrathin or thin bronchoscope toward peripheral targets. This multicentre, single-arm prospective study evaluated diagnostic performance and safety of transbronchial biopsy in bronchus sign-positive PPLs (<20 mm).

LanguageEnglish

CategoryHealthcare

FormatPDF

Pages9

Reading Time23 min

AccessFree to download

Abstract

Background

Methods

Results

Conclusion

Introduction

Problem statement: biopsy challenges in PPLs

Existing biopsy methods and limitations

Rationale for endoscopic and TBB approaches

What this study adds

What this study might affect research, practice or policy

Lung cancer Original research Balloon dilatation for bronchoscope delivery: first-inhuman trial of a novel technique for peripheral lung field access Kotaro Miyake , 1 Masahide Oki,2 Hidekazu Suzuki ,3 Hideo Saka,4 Shinji Sasada, 5 Norio Okamoto,6 Tatsuya Imabayashi ,7 Yoshihito Kogure,8 Takayuki Shiroyama, 1 Haruhiko Hirata, 1 Izumi Nagatomo ,9 Yoshito Takeda, 1 Atsushi Kumanogoh 1 ► Additional supplemental material is published online only. To view, please visit the journal online ([https://doi](https://doi). org/10.1136/thorax-2025- 223218) . For numbered affiliations see end of article. Correspondence to Dr Kotaro Miyake; kotaromiyake@imed3 . med. [osaka-u.ac.jp](osaka-u.ac.jp) Received 21 February 2025 Accepted 6 October 2025 ► [https://doi.org/10.1136/](https://doi.org/10.1136/)[ ](https://doi.org/10.1136/)[thorax-2025-223940](thorax-2025-223940) © Author(s) (or their employer(s)) 2025. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ Group. To cite: Miyake K, Oki M, Suzuki H, et al. Thorax Epub ahead of print: [please include Day Month Year] . doi:10.1136/ thorax-2025-223218 ABSTRACT Background Bronchoscopic limitations in reaching peripheral pulmonary lesions (PPLs) can compromise biopsy sensitivity, especially for small PPLs. Therefore, we developed the balloon dilatation for bronchoscope delivery (BDBD) technique to dilate bronchial pathways and facilitate bronchoscope advancement into the periphery. This study evaluated the diagnostic performance and safety profile of transbronchial biopsy using this technique. Methods This multicentre, single-arm, prospective study included patients with bronchus sign-positive PPLs measuring <20 mm. Bronchoscopy was performed using ultrathin or thin bronchoscopes under conscious sedation. When the bronchoscope could not advance further, the BDBD technique was used to approach closer to the target, followed by biopsies. The primary endpoint was the diagnostic sensitivity for malignancy in specimens obtained through the specified procedure, defined as bronchoscope advancement using balloon dilatation, direct biopsy site visualisation and absence of serious adverse events. Results Eighteen of 22 patients who underwent bronchoscopy with the BDBD technique were ultimately diagnosed with cancer. BDBD enabled bronchoscope advancement in all 18 cases without serious complications, allowed direct biopsy site visualisation in 17 and detected cancer in 14. Thus, the diagnostic sensitivity for malignancy was 77.8%(14/18) . Beyond these cases, one patient who met all procedural criteria was diagnosed with cryptococcosis. Another patient was diagnosed with cancer without direct visualisation. On average, BDBD enabled bronchoscope advancement by 2.3 bifurcations. Conclusion In this small observational study, BDBD appeared to be a promising technique for improving the diagnostic sensitivity of bronchoscopy for small PPLs. Further validation is necessary in large cohorts. Trial registration number jRCT2052220174 INTRODUCTION Accurate diagnosis of peripheral pulmonary lesions (PPLs) is a significant challenge in pulmonary medicine. Two primary methods are used for biopsy of suspected PPLs. Transthoracic needle aspiration is preferred because | WHAT IS ALREADY KNOWN ON THIS TOPIC
⇒ A biopsy of peripheral pulmonary lesions (PPLs) requires high sensitivity while maintaining procedural simplicity; however, conventional bronchoscopy is limited by airway narrowing, preventing access to peripheral lung fields. Therefore, successful biopsy of PPLs that cannot be directly visualised by the bronchoscope remains a major challenge in bronchoscopy.
WHAT THIS STUDY ADDS | | --- | | ⇒ This first-in-human trial demonstrated that the balloon dilatation for bronchoscope delivery (BDBD) technique enables bronchoscopic access to peripheral lung regions by expanding the airway, achieving a diagnostic sensitivity of 77

FAQs

What problem does the BDBD technique address in bronchoscopy?

It addresses bronchoscopic limitations in reaching peripheral pulmonary lesions by dilating the bronchial pathway, which helps advance the bronchoscope to the peripheral lung region for biopsy.

Who was included in the study and how were bronchoscopy procedures performed?

Patients with bronchus sign-positive PPLs measuring under 20 mm were included. Bronchoscopy used ultrathin or thin bronchoscopes under conscious sedation, and BDBD was applied when the scope could not advance further.

What diagnostic performance and safety results were reported?

Among 22 patients, 18 were diagnosed with cancer after BDBD-assisted bronchoscopy. BDBD enabled advancement in all 18 without serious complications, provided direct biopsy site visualisation in 17, and yielded a reported malignancy diagnostic sensitivity of 77.8% (14/18).

What do the authors conclude and what is the next step?

In this small observational study, BDBD appeared promising for improving diagnostic sensitivity for small PPLs. Further validation is required in larger cohorts.

Sep 23, 2026

Uploaded by hdkawk