Using a portable terahertz spectrometer to measure the optical properties of<i>in vivo</i>human skin

Echchgadda, Ibtissam; Grundt, Jessica A.; Tarango, Melissa; Ibey, Bennett L.; Tongue, Thomas; Liang, Min; Xin, Hao; Wilmink, Gerald J.

doi:10.1117/1.jbo.18.12.120503

Cited by 38 publications

(20 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The variation in the dielectric constant is due mainly to the different levels of moisture in the subjects. The measured values showed considerable consistency with those reported previously5051. Finally, using Eq.…”

Section: Resultssupporting

confidence: 90%

Morphology of human sweat ducts observed by optical coherence tomography and their frequency of resonance in the terahertz frequency region

Tripathi

Miyata

Ishai

et al. 2015

Sci Rep

View full text Add to dashboard Cite

It is crucial to understand the various biological effects induced by terahertz (THz) electromagnetic waves with the rapid development of electronic and photonic devices operating in the THz frequency region. The presence of sweat glands plays an important role in THz wave interactions with human skin. We investigated the morphological features of sweat ducts using optical coherence tomography (OCT) to further understand such phenomena. We observed remarkable features of the ducts, such as their clear helical structure. The intersubject and intrasubject variations in the diameter of sweat ducts were considerably smaller than the variations in other structural parameters, such as length and number of turns. Based on the sweat duct dimensions and THz dielectric properties of skin measured using terahertz time-domain spectroscopy (THz-TDS), we calculated the resonating frequency of the sweat duct under the assumption of it functioning as a helical antenna. Here, we show that the resonance frequency in the axial mode of operation lies in the THz wave region with a centre frequency of 0.44 ± 0.07 THz. We expect that these findings will further our understanding of the various health consequences of the interaction of THz waves with human beings.

show abstract

Section: Resultssupporting

confidence: 90%

Morphology of human sweat ducts observed by optical coherence tomography and their frequency of resonance in the terahertz frequency region

Tripathi

Miyata

Ishai

et al. 2015

Sci Rep

View full text Add to dashboard Cite

show abstract

“…This affords an opportunity for employing THz spectroscopy on clinical demyelinating disease discrimination, since THz spectroscopy has been used for studying human skin in vivo 36 . Furthermore, mathematical models have shown that in vivo THz spectroscopy of the brain is plausible at higher power levels of THz source 15, 37, 38 .…”

Section: Discussionmentioning

confidence: 99%

Terahertz Spectroscopic Diagnosis of Myelin Deficit Brain in Mice and Rhesus Monkey with Chemometric Techniques

Zou

Cui

et al. 2017

Sci Rep

View full text Add to dashboard Cite

While myelin deficit of the central nervous system leads to several severe diseases, the definitive diagnostic means are lacking. We proposed and performed terahertz time-domain spectroscopy (THz-TDS) combined with chemometric techniques to discriminate and evaluate the severity of myelin deficit in mouse and rhesus monkey brains. The THz refractive index and absorption coefficient of paraffin-embedded brain tissues from both normal and mutant dysmyelinating mice are shown. Principal component analysis of time-domain THz signal (PCA-tdTHz) and absorption-refractive index relation of THz spectrum identified myelin deficit without exogenous labeling or any pretreatment. Further, with the established PCA-tdTHz, we evaluated the severity of myelin deficit lesions in rhesus monkey brain induced by experimental autoimmune encephalomyelitis, which is the most-studied animal model of multiple sclerosis. The results well matched the pathological analysis, indicating that PCA-tdTHz is a quick, powerful, evolving tool for identification and evaluation myelin deficit in preclinical animals and potentially in para-clinical human biopsy.

show abstract

“…The terahertz (THz) spectroscopic technique, which is a novel medical imaging modality, 9 has received a attention for its benign nature (noninvasive and nonionizing) toward humans and its high sensitivity to biomolecules 10,11 and tissues. [12][13][14] In recent decades, the THz spectroscopic technique has been used to identify tumors on skin, [15][16][17] breast, [18][19][20] colon, [21][22][23] liver, 24 and other locations. All of the results show that the THz spectroscopic technique has potential for safely identifying disease in tissue samples.…”

Section: Introductionmentioning

confidence: 99%

“…9 The THz absorption reported in these experiments is primarily a result of the interstitial water content of the brain tumor and normal tissue. Most of the tissues studied by THz spectroscopy can be classified into three forms: fresh tissues, 12,13,16 frozen tissues, 26 and paraffin-embedded tissues. 23,24 The fresh tissues contain a large volume of water (THz absorption coefficient is about 240 cm −1 at 1 THz), 9 which contribute most to THz absorption in fresh tissues, while frozen tissues 26 and paraffin-embedded tissues 23,24 have much lower THz absorption than that of fresh tissues by excluding water.…”

Section: Introductionmentioning

confidence: 99%

Terahertz pulsed spectroscopy of paraffin-embedded brain glioma

et al. 2014

View full text Add to dashboard Cite

Abstract. The refractive indices, absorption coefficients, and complex dielectric constants of paraffin-embedded brain glioma and normal brain tissues have been measured by a terahertz time-domain spectroscopy (THz-TDS) system in the 0.2-to 2.0-THz range. The spectral differences between gliomas and normal brain tissues were obtained. Compared with normal brain tissue, our results indicate that paraffin-embedded brain gliomas have a higher refractive index, absorption coefficient, and dielectric constant. Based on these results, the best THz frequencies for different methods of paraffin-embedded brain glioma imaging, such as intensity imaging, coherent imaging with continuum THz sources, and THz pulsed imaging with short-pulsed THz sources, are analyzed.

show abstract

Using a portable terahertz spectrometer to measure the optical properties ofin vivohuman skin

Cited by 38 publications

References 16 publications

Morphology of human sweat ducts observed by optical coherence tomography and their frequency of resonance in the terahertz frequency region

Morphology of human sweat ducts observed by optical coherence tomography and their frequency of resonance in the terahertz frequency region

Terahertz Spectroscopic Diagnosis of Myelin Deficit Brain in Mice and Rhesus Monkey with Chemometric Techniques

Terahertz pulsed spectroscopy of paraffin-embedded brain glioma

Contact Info

Product

Resources

About