Special section guest editorial: advances in terahertz biomedical science and applications

The Journal of Biomedical Optics (JBO) has published this special section of papers to capture the most recent advances in THz technology and innovative THz instruments and methods in biology and medicine. A few of the papers in this special section are dedicated to similar biomedical applications of novel optical tools from the neighboring infrared (IR) range. Two papers of the special section consider modern problems of oncodiagnosis. In the research article ‘Development of oral cancer tissue-mimicking phantom based on polyvinyl chloride plastisol and graphite for terahertz frequencies’, authors have introduced a new type of a water-free tissue-mimicking phantom for THz biophotonics. This phantom is based on graphite powders embedded into a polyvinyl chloride plastisol matrix. The effective THz optical properties of such a phantom can be managed in a wide range by changing its composition, thus allowing to mimic the THz optical properties of various biological tissues

Biomedical applications of sapphire shaped crystals

We have proposed novel medical instrument

Wavelet-domain de-noising of OCT images of human brain malignant glioma

We have proposed a wavelet-domain de-noising technique for imaging of human brain malignant glioma by optical coherence tomography (OCT). It implies OCT image decomposition using the direct fast wavelet transform, thresholding of the obtained wavelet spectrum and further inverse fast wavelet transform for image reconstruction. By selecting both wavelet basis and thresholding procedure, we have found an optimal wavelet filter, which application improves differentiation of the considered brain tissue classes – i.e. malignant glioma and normal/intact tissue. Namely, it allows reducing the scattering noise in the OCT images and retaining signal decrement for each tissue class. Therefore, the observed results reveals the wavelet-domain de-noising as a prospective tool for improved characterization of biological tissue using the OCT

Feasibility test of a sapphire cryoprobe with optical monitoring of tissue freezing

This article describes a sapphire cryoprobe as a promising solution to the significant problem of modern cryosurgery that is the monitoring of tissue freezing. This probe consists of a sapphire rod manufactured by the edge-defined film-fed growth technique from Al2O3 melt and optical fibers accommodated inside the rod and connected to the source and the detector. The probe's design enables detection of spatially resolved diffuse reflected intensities of tissue optical response, which are used for the estimation of tissue freezing depth. The current type of the 12.5-mm diameter sapphire probe cooled down by the liquid nitrogen assumes a superficial cryoablation. The experimental test made by using a gelatin-intralipid tissue phantom shows the feasibility of such concept, revealing the capabilities of monitoring the freezing depth up to 10 mm by the particular instrumentation realization of the probe. This justifies a potential of sapphire-based instruments aided by optical diagnosis in modern cryosurgery

Biomedical applications of sapphire shaped crystals

We have proposed novel medical instrument

SPIRou @CFHT: design of the instrument control system

ABSTRACT SPIRou is a near-IR (0.98-2.35µm), echelle spectropolarimeter / high precision velocimeter being designed as a nextgeneration instrument for the 3.6m Canada-France-Hawaii Telescope on Mauna Kea, Hawaii, with the main goals of detecting Earth-like planets around low-mass stars and magnetic fields of forming stars. The unique scientific and technical capabilities of SPIRou are described in a series of eight companion papers. In this paper, the means of controlling the instrument are discussed. Most of the instrument control is fairly normal, using off-the-shelf components where possible and reusing already available code for these components. Some aspects, however, are more challenging. In particular, the paper will focus on the challenges of doing fast (50 Hz) guiding with 30 mas repeatability using the object being observed as a reference and on thermally stabilizing a large optical bench to a very high precision (~1 mK)

SPIRou @CFHT: design of the instrument control system

SPIRou is a near-IR (0.98-2.35\u3bcm), echelle spectropolarimeter / high precision velocimeter being designed as a next-generation instrument for the 3.6m Canada-France-Hawaii Telescope on Mauna Kea, Hawaii, with the main goals of detecting Earth-like planets around low-mass stars and magnetic fields of forming stars. The unique scientific and technical capabilities of SPIRou are described in a series of eight companion papers. In this paper, the means of controlling the instrument are discussed. Most of the instrument control is fairly normal, using off-the-shelf components where possible and reusing already available code for these components. Some aspects, however, are more challenging. In particular, the paper will focus on the challenges of doing fast (50 Hz) guiding with 30 mas repeatability using the object being observed as a reference and on thermally stabilizing a large optical bench to a very high precision ( 3c1 mK).Peer reviewed: YesNRC publication: Ye