Brain tumor imaging of rat fresh tissue using terahertz spectroscopy

Yamaguchi, Sayuri; Fukushi, Yasuko; Kubota, Oichi; Itsuji, Takeaki; Ouchi, Toshihiko; Yamamoto, Seiji

doi:10.1038/srep30124

Cited by 134 publications

(93 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…For example, Zou et al employed terahertz spectroscopy to diagnose myelin deficits in animal brain samples without exogenous labeling or any pretreatment . However, the spatial resolution in previous studies was very limited, making fine structures, such as the myelin sheath, difficult to visualize . The use of synchrotron radiation‐based infrared microspectroscopy shows obvious advantages, including high brightness, a wide spectrum range (≈1–16.67 µm), a high spectrum resolution, and a high spatial resolution (≈3 µm), allowing us to visualize myelin structures at the micrometer scale with optimized infrared illumination.…”

Section: Discussionmentioning

confidence: 99%

Myelin Sheath as a Dielectric Waveguide for Signal Propagation in the Mid‐Infrared to Terahertz Spectral Range

Liu

Chang

Qiao

et al. 2018

Adv Funct Materials

196

View full text Add to dashboard Cite

The myelin sheath enables dramatic speed enhancement for signal propagation in nerves. In this work, myelinated nerve structure is experimentally and theoretically studied using synchrotron-radiation-based Fourier-transform infrared microspectroscopy. It is found that, with a certain mid-infrared to terahertz spectral range, the myelin sheath possesses a ≈2-fold higher refraction index compared to the outer medium or the inner axon, suggesting that myelin can serve as an infrared dielectric waveguide. By calculating the correlation between the material characteristics of myelin and the radical energy distribution in myelinated nerves, it is demonstrated that the sheath, with a normal thickness (≈2 µm) and dielectric constant in nature, can confine the infrared field energy within the sheath and enable the propagation of an infrared signal at the millimeter scale without dramatic energy loss. The energy of signal propagation is supplied and amplified when crossing the nodes of Ranvier via periodic relay. These findings provide the first model for explaining the mechanism of infrared and terahertz neurotransmission through myelinated nerves, which may promote the development of biological-tissue label-free detection, biomaterial-based sensors, neural information, and noninvasive brain-machine interfaces.

show abstract

Section: Discussionmentioning

confidence: 99%

Myelin Sheath as a Dielectric Waveguide for Signal Propagation in the Mid‐Infrared to Terahertz Spectral Range

Liu

Chang

Qiao

et al. 2018

Adv Funct Materials

196

View full text Add to dashboard Cite

show abstract

“…Therefore, TRI may serve as a high-sensitivity detector for glioma, allowing neurosurgeons to ‘see’ tumor regions without the use of contrast agents during glioma surgery. Several papers reported on the possibility of glioma detection using TRI234041. However they used only fresh rat or paraffin-embedded samples.…”

Section: Discussionmentioning

confidence: 99%

Terahertz reflectometry imaging for low and high grade gliomas

Kang

et al. 2016

Sci Rep

100

View full text Add to dashboard Cite

Gross total resection (GTR) of glioma is critical for improving the survival rate of glioma patients. One of the greatest challenges for achieving GTR is the difficulty in discriminating low grade tumor or peritumor regions that have an intact blood brain barrier (BBB) from normal brain tissues and delineating glioma margins during surgery. Here we present a highly sensitive, label-free terahertz reflectometry imaging (TRI) that overcomes current key limitations for intraoperative detection of World Health Organization (WHO) grade II (low grade), and grade III and IV (high grade) gliomas. We demonstrate that TRI provides tumor discrimination and delineation of tumor margins in brain tissues with high sensitivity on the basis of Hematoxylin and eosin (H&E) stained image. TRI may help neurosurgeons to remove gliomas completely by providing visualization of tumor margins in WHO grade II, III, and IV gliomas without contrast agents, and hence, improve patient outcomes.

show abstract

“…The dielectric values, expressed as the real ( ϵ ′) and imaginary ( ϵ ″) parts of the complex permittivity, refractive index, and absorption coefficient, are set out in Table . The values are derived from data from Huang et al [], Jördens et al [], Png et al [], Sy et al [], Sim et al [,], Guseva et al [], Yamaguchi et al [], Hernandez‐Cardoso et al [], Hübers et al [], and Mizuno et al [], and the analysis of mixing formulae is from Jördens et al [] and Ney and Abdulhalim []. A comprehensive outline of the derivation is provided in the supplementary material (S2).…”

Section: Introductionmentioning

confidence: 99%

“…The stratum corneum has only 15% water content, and thus ϵ ″ remains high in the model. The values are derived from Huang et al [], Jördens et al [], Png et al [], Sy et al [], Sim et al [,], Guseva et al [], Yamaguchi et al [], Hernandez‐Cardoso et al [], Hübers et al [] and Mizuno et al [].…”

Section: Introductionmentioning

confidence: 99%

Computational phantom study of frozen melanoma imaging at 0.45 terahertz

Vilagosh

Lajevardipour

Wood

2019

Bioelectromagnetics

View full text Add to dashboard Cite

Terahertz radiation (THz) is highly absorbed by liquid water. This creates the possibility of medical imaging on the basis of the water content difference between normal and diseased tissue. The effective penetration of THz is limited, however, to a tissue depth of 0.2–0.3 mm at body temperature. A unique feature of the 0.1–2.0 THz frequency is that there is a high disparity between liquid water absorption and ice absorption, with ice being 100 times more permeable to the radiation than liquid water. This results in 90% of the radiation surviving to 1.0 mm in ice, permitting the imaging of frozen tissues to a depth of 5.0 mm. This method is practical as an in vivo procedure before or during surgical excision. Finite difference time domain (FDTD) computational modeling of frozen normal skin and frozen melanoma was undertaken using tissue phantoms. The study suggests that sufficient contrast exists to differentiate normal frozen skin and melanoma on the basis of the difference of water content alone. When the melanin pigment in melanomas is modeled as a significant absorber of THz, the contrast changes. Based on the modeling, further exploration of the “THz‐skin freeze” imaging technique is justified. In the modeling, the boundary between the frozen tissue and non‐frozen tissue is shown to be strongly reflective. If the reflective properties of the boundary are substantiated, the “THz‐skin freeze” technique will have applications in other areas of skin diagnostics and therapeutics. Bioelectromagnetics. 40:118–127, 2019. © 2019 Bioelectromagnetics Society

show abstract

Brain tumor imaging of rat fresh tissue using terahertz spectroscopy

Cited by 134 publications

References 22 publications

Myelin Sheath as a Dielectric Waveguide for Signal Propagation in the Mid‐Infrared to Terahertz Spectral Range

Myelin Sheath as a Dielectric Waveguide for Signal Propagation in the Mid‐Infrared to Terahertz Spectral Range

Terahertz reflectometry imaging for low and high grade gliomas

Computational phantom study of frozen melanoma imaging at 0.45 terahertz

Contact Info

Product

Resources

About