Feasibility of manual bronchial branch reading technique in navigating conventional rEBUS bronchoscopy in the evaluation of peripheral pulmonary lesion.

Background: Although radial endobronchial ultrasound (rEBUS) is an important verification tool in guided bronchoscopy, a navigational route was not provided. Manual airway mapping allows the bronchoscopist to translate the bronchial branching in computed tomography (CT) into a comparable bronchoscopic road map. We aimed to explore the feasibility of this technique in navigating conventional rEBUS bronchoscopy in the localisation of peripheral pulmonary lesion by determining navigation success and diagnostic yield.

Methods: Retrospective review of consecutive rEBUS bronchoscopy performed with a 6.2 mm conventional bronchoscope navigated via manual bronchial branch reading technique over 18 months.

Results: Ninety-eight target lesions were included. Median lesion size was 2.67 cm (IQR 2.22-3.38) with 96.9% demonstrating positive CT bronchus sign. Majority (86.7%) of lesions were situated in between the third and fifth airway generations. Procedure was performed with endotracheal intubation in 43.9% and fluoroscopy in 72.4%. 98.9% of lesions were successfully navigated and verified by rEBUS following the pre-planned airway road map. Bidirectional guiding device was employed in 29.6% of cases. Clinical diagnosis was secured in 88.8% of cases, majority of which were malignant disease. The discrepancy between navigation success and diagnostic yield was 10.1%. Target PPL located within five airway generations was associated with better diagnostic yield (95.1% vs. 58.8%, P < 0.001). There was 1 (1.0%) pneumothorax in our cohort.

Conclusions: Manual bronchial branch reading technique in combination with conventional rEBUS is feasible in localisation of PPL, especially for lesions located within the first five airway generations.