Dual instrument for in vivo and ex vivo OCT imaging in an ENT department

Abstract

A dual instrument is assembled to investigate the usefulness of optical coherence tomography (OCT) imaging in an ear, nose and throat (ENT) department. Instrument 1 is dedicated to in vivo laryngeal investigation, based on an endoscope probe head assembled by compounding a miniature transversal flying spot scanning probe with a commercial fiber bundle endoscope. This dual probe head is used to implement a dual channel nasolaryngeal endoscopy-OCT system. The two probe heads are used to provide simultaneously OCT cross section images and en face fiber bundle endoscopic images. Instrument 2 is dedicated to either in vivo imaging of accessible surface skin and mucosal lesions of the scalp, face, neck and oral cavity or ex vivo imaging of the same excised tissues, based on a single OCT channel. This uses a better interface optics in a hand held probe. The two instruments share sequentially, the swept source at 1300 nm, the photo-detector unit and the imaging PC. An aiming red laser is permanently connected to the two instruments. This projects visible light collinearly with the 1300 nm beam and allows pixel correspondence between the en face endoscopy image and the cross section OCT image in Instrument 1, as well as surface guidance in Instrument 2 for the operator. The dual channel instrument was initially tested on phantom models and then on patients with suspect laryngeal lesions in a busy ENT practice. This feasibility study demonstrates the OCT potential of the dual imaging instrument as a useful tool in the testing and translation of OCT technology from the lab to the clinic. Instrument 1 is under investigation as a possible endoscopic screening tool for early laryngeal cancer. Larger size and better quality cross-section OCT images produced by Instrument 2 provide a reference base for comparison and continuing research on imaging freshly excised tissue, as well as in vivo interrogation of more superficial skin and mucosal lesions in the head and neck patient.

Surface imaging of metallic material fractures using optical coherence tomography

“…Another advantage of opting for OCT instead of an SEM is the possibility of assembling small, compact OCT mobile units and handheld scanning probes [18][19][20][21][22]. Such units make on-site evaluations possible.…”

Towards a research pole in photonics in Western Romania

“…For our current project we approach GS-based handheld probes [45], as well as endoscopic miniature scanning heads. Another research avenue is on the optimal scanning algorithms that have to be employed in OCT (but more general, in Biomedical Imaging) to obtain the most -in terms of speed (for in vivo real-time imaging) and artifact-free imagesfrom the OCT systems.…”

“…Combination of three technologies in one system, OCT, scanning laser ophthalmoscopy and adaptive optics and highest limit in vivo obtained in en-face images as thin as 3 μm were reported. Resources were oriented towards extending the expertise acquired from ophthalmology to cell imaging and OCT applicability to image embryos [49] and more recently, towards OCT endoscopy [45]. Expertise was extended to dentistry [47], to imaging of basal cell carcinoma and to art conservation [50].…”

Laser scanners: from industrial to biomedical applications

“…Another line of work is in the development of different control structures of the device to minimize the response time of the device or its precision [32]. The application of 1D and 2D GSs in assemblies such as handheld scanning probes for OCT have also been completed [51] and is a promising direction of research. These aspects, of the investigation of the programming part of the devices, are in conjunction with those of major companies to improve the constructive and functional aspects of GSs [23], in terms of motors, pivots, moving elements, command, control and testing.…”