A Novel Method for In Vivo Imaging of Solitary Lung Nodules Using Navigational Bronchoscopy and Confocal Laser Microendoscopy

Solitary pulmonary nodules (SPN) have become increasingly prevalent and diagnostic management remains challenging. We demonstrate a novel technique in which probe-based confocal endomicroscopy (pCLE) could be performed to microimage SPN in vivo and in real-time. Two confocal wavelengths (488 and 660 nm with methylene blue (MB)) were used for elastin network and cellular imaging, respectively using pCLE in conjunction with r-EBUS and virtual navigation. In the first case, the 1-mm Alveoflex^® was used to image a metastatic melanoma in a subcentimetric nodule in the right middle lobe. In the next case, a malignant 2-cm nodule in the posterior segment of the upper lobe was imaged using the smaller 0.6-mm Cholangioflex^®. Lastly, we present a benign case revealing confocal characteristics of a nodular lipid pneumonitis. This reports for the first time the feasibility and utility of pCLE in vivo microimaging of SPN using either the Alveoflex or Cholangioflex miniprobes in addition to 660 nm/MB imaging.