Investigations on the potential of optical coherence tomography as an imaging tool for eustachian tube

Abstract

The purpose of this study was to explore the feasibility of eustachian tube optical coherence tomography (ET-OCT) for imaging the pharyngeal region of the eustachian tube (ET). Ten subjects with ear complaints underwent ET-OCT guided by nasal endoscopy, and ET-OCT examination was performed on both sides of each subject's ETs. The process and resulting images were analysed. Ten subjects ranging from 21 to 73 years old (45 ± 14.77) were enrolled in this study. Eighteen ET-OCT imaging examinations were completed. The mean duration of each examination was 2.80 ± 1.62 min (ranging from 2 to 7 min). There were no adverse events or complications. In some subjects, the ET-OCT images clearly presented the microstructures of the ET wall, including the lumen, mucosa, submucosa, cartilage and plica. However, in some subjects, it showed different characteristics, such as an unclear hierarchy and secretions in the lumen. ET-OCT may help to distinguish the structural composition of the ET and elucidate related pathophysiological mechanisms. It is a valuable imaging tool suited for the ET, with potential diagnostic value in determining the morphology of the lumen, intraluminal mucosa and submucosal tissue in the pharyngeal region of the ET.

Intravascular Ultrasonography (IVUS)—A Tool for Imaging the Eustachian Tube?

“…However, in recent years, some promising results have been obtained in imaging the ET using OCT. In this study, in contrast to the predominant current OCT studies [ 16 , 17 , 18 ], the approach of Hellweg et al 1996 [ 19 ] was revisited to image the ET using an IVUS probe. State-of-the-art probes were used and, in addition, transnasal insertion was performed instead of peroral insertion.…”

“…Imaging techniques are the basis by which to investigate and better understand the mechanisms of ET. Until now, different techniques have been used to image the ET, such as radiography, computed tomography (CT) [ 9 , 10 ], cone-beam computed tomography (CBCT) [ 11 , 12 ], magnetic resonance tomography (MRI) [ 13 , 14 ], endoscopy [ 2 , 15 ], optical coherence tomography (OCT) [ 16 , 17 , 18 ] and endoluminal sonography with transfer of Intravascular Ultrasonography (IVUS) used in cardiology [ 19 ]. Nevertheless, so far, there is still a lack of clinically suitable examination methods [ 20 ].…”

“…The OCT has a better resolution, in the range of 10–20 µm, where the IVUS has a resolution of 100–200 µm. The latest attempts and successes in the experimental application were achieved by optical coherence tomography [ 16 , 17 , 18 ]. Furthermore, the first clinical study was performed with promising results [ 17 ].…”

“…The latest attempts and successes in the experimental application were achieved by optical coherence tomography [ 16 , 17 , 18 ]. Furthermore, the first clinical study was performed with promising results [ 17 ]. They also used a transnasal approach, as in the optical coherence tomography study presented earlier [ 18 ].…”

Comparative study of optical coherence tomograph and histological images of eustachian tube nasopharyngeal region and adjacent structures in vivo and ex-vivo miniature pigs

“…In an ex-vivo sheep study, superficial structures including the respiratory epithelium, submucosa, cartilage, mucous glands, lymphoid follicles and bone could be identified [ 1 ]. Our previous study demonstrates that OCT imaging technology can be used to examine the eustachian tube via its pharyngeal opening in humans, obtaining high-resolution OCT images [ 2 ]. It can delineate the morphology of the lumen, mucosa and submucosa.…”