A Handheld Fiber-Optic Probe to Enable Optical Coherence Tomography of Oral Soft Tissue

Abstract

This study presents a highly miniaturized, handheld probe developed for rapid assessment of soft tissue using optical coherence tomography (OCT). OCT is a non-invasive optical technology capable of visualizing the sub-surface structural changes that occur in soft tissue disease such as oral lichen planus. However, usage of OCT in the oral cavity has been limited, as the requirements for high-quality optical scanning have often resulted in probes that are heavy, unwieldy and clinically impractical. In this paper, we present a novel probe that combines an all-fiber optical design with a light-weight magnetic scanning mechanism to provide easy access to the oral cavity. The resulting probe is approximately the size of a pen (10 mm × 140 mm) and weighs only 10 grams. To demonstrate the feasibility and high image quality achieved with the probe, imaging is performed on the buccal mucosa and alveolar mucosa during routine clinical assessment of six patients diagnosed with oral lichen planus. Results show the loss of normal tissue structure within the lesion, and contrast this with the clear delineation of tissue layers in adjacent inconspicuous regions. The results also demonstrate the ability of the probe to acquire a three-dimensional data volume by manually sweeping across the surface of the mucosa. The findings of this study show the feasibility of using a small, lightweight probe to identify pathological features in oral soft tissue.

Site-Coded Oral Squamous Cell Carcinoma Evaluation by Optical Coherence Tomography (OCT): A Descriptive Pilot Study

“…All the details described for the parameters listed above are also reported in similar studies investigating the OCT discriminatory potential of healthy oral mucosa alone [ 3 , 14 , 31 , 32 , 33 , 34 ].…”

Characteristics of Clinically Classified Oral Lichen Planus in Optical Coherence Tomography: A Descriptive Case-Series Study

“…For the imaging of OLP and leukoplakia of the human oral mucosa, we used the fiber probe OCT system described in [ 40 ] clinically on 13 patients with OLP and 2 patients with leukoplakia for comparison. The scanning optics of the miniprobe consists of a customized spliced GRIN fiber optic that is laterally deflected by a magnetic scanning system based on a ring magnet (1 mm outer diameter; attached to the fiber optic) and three copper wire coils which are used to drive the scanning motion of the fiber probe.…”

“…The scanning optics of the miniprobe consists of a customized spliced GRIN fiber optic that is laterally deflected by a magnetic scanning system based on a ring magnet (1 mm outer diameter; attached to the fiber optic) and three copper wire coils which are used to drive the scanning motion of the fiber probe. The fiber probe with a scanning system is located inside a stainless-steel cylinder (10 mm diameter, 140 mm length) with a 4 angled sapphire glass window (8 mm × 0.15 mm (diameter × width), UQG Optics Ltd., Cambridge, UK) at the proximal end of the probe (right part in Figure 1 ) [ 40 ]. The miniprobe is connected to a Fourier domain OCT system based on a swept source laser (AXP50125-6, Axsun Technologies Inc., Billerica, MA, USA), with a central wavelength of 1285 nm, a sweep range of 135 nm and a 100 kHz tuning rate.…”

“…In this case-series study, we present the results of the depth-resolved OCT imaging of visually diagnosed OLP of the human oral mucosa in vivo during follow-up examination by means of the clinical use of a customized fiber-based probe [ 40 ]. For differentiation, we also included two patients with visually diagnosed leukoplakia with and without dysplastic change in our study.…”

Single-fiber probes for combined sensing and imaging in biological tissue: recent developments and prospects

“…Furthermore, single-fiber-based probes may also enable sensing + imaging of pathological features [ 82 ] or cancerous tissues [ 83 ], providing valuable information about tumor margins and tissue composition. They also have potential uses in cardiovascular imaging to visualize blood vessels, assess blood flow, and detect plaque buildup.…”