Improved endoscopic optical coherence microscopy for imaging of humans airways in patients

We recently developed an endoscopic optical coherence microscope (eOCM) prototype and successfully imaged the nasal epithelium of humans. Based on the experience from previous tests in probands we designed a new compact and userfriendly eOCM-prototype for clinical use.

The first eOCM prototype consisted of high power broadband supercontinuum light source, a customized 400nm spectrometer and a rigid semi-contact endoscope with a length of 45 mm and a diameter of 3 mm mounted on a handheld probe. We achieved a lateral and axial resolution of less than 1.5 µm with a grin lens based objective (0.5 NA). Imaging speed reached up to 150 frames/s.

In healthy human volunteers imaging the concha nasalis eOCM the epithelium and the subepithelial tissue including mucus glands and blood vessels were visible. Beating of cilia was also visualized and the ciliary beat frequency could be determined.

The new eOCM device is designed for a clinical use. It is smaller and has less weight. It contains a better-corrected objective which leads to a bigger field of view and a higher resolution. The length of endoscope is extended to 60 mm for better accessibility of nasal airways. Inside the 3 mm endoscope we integrated a micro-camera with a footprint of 1 mm2 and white light illumination and a 0.5 mm Ø channel for application or suctions. To apply substances at the tip of the endoscope or to remove mucus by suction, a 0.5 mm Ø channel for application was included.

Our tests in humans have shown that eOCM has great potential for imaging functional changes of the upper airways in patients. The new eOCM provides the foundation for a clinical use.

*Presenting author