Simultaneous dual-band optical coherence tomography for endoscopic applications

Abstract

Dual-band optical coherence tomography (OCT) can greatly enhance the imaging contrast with potential applications in functional (spectroscopic) analysis. A new simultaneous dual-band Fourier domain mode-locked swept laser configuration for dual-band OCT is reported. It was based on a custom-designed dual-channel driver to synchronize two different wavelength bands at 1310 and 1550 nm, respectively. Two lasing wavelengths were swept simultaneously from 1260 to 1364.8 nm for the 1310-nm band and from 1500 to 1604 nm for the 1550-nm band at an A-scan rate of 45 kHz. Broadband wavelength-division multiplexing was utilized to couple two wavelength bands into a common catheter for circumferential scanning to form dual-band OCT. The proposed dual-band OCT scheme was applied to endoscopic OCT imaging of mouse esophageal wall ex vivo and human fingertip in vivo to justify the feasibility of the proposed imaging technique. The proposed dual-band OCT system is fast and easy to be implemented, which allows for in vivo high-speed biomedical imaging with potential applications in spectroscopic investigations for endoscopic imaging.

Tumor xenograft animal models for esophageal squamous cell carcinoma

“…Active research is devoted in this area for ESCC research. Initial attempt has been made to deploy the capacity of optical coherence tomography to reveal various layers of the mouse esophageal wall in a high resolution manner [ 29 ]. Such effort has launched the research towards this direction by further examining the image contrast-enhancing effects associated with contrast agents like nanoparticles [ 30 ].…”

Sensitivity enhancement in swept-source optical coherence tomography by parametric balanced detector and amplifier

“…Leonhardt et al explored the nonlinear optical frequency conversion to Fourier domain mode-locked (FDML) laser, which not only shifted the working wavelength, but also increased the wavelength sweep rate of FDML laser [22]. Zhu et al, Xu et al, and Yu et al reported dual-band and tri-band SS-OCT systems, which expanded the working bandwidth of SS-OCT systems, thus improved the resolution through generating an idler band by using the FDML laser's output as the signal to the fiber optical parametric process [23][24][25]. Recently, Zhao et al demonstrated the imaging enhancement and time gating effects on charge-coupled detector (CCD)-based spectral-domain optical coherence microscopy (SD-OCM) in turbid media by using optical parametric amplifier (OPA) with a type I BBO crystal [26].…”