Endoscopic Doppler optical coherence tomography and autofluorescence imaging of peripheral pulmonary nodules and vasculature.

Tawimas Shaipanich,Stephen Lam,Geoffrey Hohert,Hamid Pahlevaninezhad,Wei Zhang,Alexander Ritchie,Calum MacAulay,Anthony M. D. Lee,Diana N. Ionescu,Pierre Lane

doi:10.1364/boe.6.004191

Abstract

We present the first endoscopic Doppler optical coherence tomography and co-registered autofluorescence imaging (DOCT-AFI) of peripheral pulmonary nodules and vascular networks in vivo using a small 0.9 mm diameter catheter. Using exemplary images from volumetric data sets collected from 31 patients during flexible bronchoscopy, we demonstrate how DOCT and AFI offer complementary information that may increase the ability to locate and characterize pulmonary nodules. AFI offers a sensitive visual presentation for the rapid identification of suspicious airway sites, while co-registered OCT provides detailed structural information to assess the airway morphology. We demonstrate the ability of AFI to visualize vascular networks in vivo and validate this finding using Doppler and structural OCT. Given the advantages of higher resolution, smaller probe size, and ability to visualize vasculature, DOCT-AFI has the potential to increase diagnostic accuracy and minimize bleeding to guide biopsy of pulmonary nodules compared to radial endobronchial ultrasound, the current standard of care.

Highlights

Accurate, safe, and timely diagnosis is crucial in the clinical management of suspicious CTscan detected pulmonary nodules to guide clinical decisions and avoid further unnecessary invasive tests for patients with benign tissue
radial endobronchial ultrasound (R-EBUS) has proven to be a powerful technique in visualizing solid large nodules [6, 7] it often fails to detect sub-solid or small pulmonary nodules [7]
As there is no depthencoding of the Autofluorescence imaging (AFI) signal, the AFI signal for each angular position is averaged over the duration of the Optical coherence tomography (OCT) A-scans

Summary

Introduction

Safe, and timely diagnosis is crucial in the clinical management of suspicious CTscan detected pulmonary nodules to guide clinical decisions and avoid further unnecessary invasive tests for patients with benign tissue. Depending on the proximity of nodules to the pleural surface, CT-guided transthoracic needle aspiration biopsy (TNAB) or transbronchial lung biopsy can be used for sample collection. The former has high diagnostic yield (~90%) [1, 2] and considerable risk of complications such as pneumothorax [2, 3]. R-EBUS has proven to be a powerful technique in visualizing solid large nodules [6, 7] it often fails to detect sub-solid or small pulmonary nodules [7]. The relatively large diameter of current R-EBUS probes (1.4 mm) restricts their access to small peripheral airways. There is an unmet clinical need for tools that localize and guide sample collection in the peripheral airways

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Results

Conclusion