The progress and perspectives of terahertz technology for diagnosis of neoplasms: a review

Abstract

Over the past few decades, significant attention has been paid to the biomedical applications of terahertz (THz) technology. Nowadays, THz spectroscopy and imaging have allowed numerous demanding problems in the biological, medical, food, plant and pharmaceutical sciences to be solved. Among the biomedical applications, the label-free diagnosis of malignant and benign neoplasms represents one of the most attractive branches of THz technology. Despite this attractiveness, THz diagnosis methods are still far from being ready for use in medical practice. In this review, we consider modern research results in the THz diagnosis of malignant and benign neoplasms, along with the topical research and engineering problems which restrain the translation of THz technology to clinics. We start by analyzing the common models of THz-wave-tissue interactions and the effects of tissue exposure to THz waves. Then, we discuss the existing modalities of THz spectroscopic and imaging systems, which have either already been applied in medical imaging, or hold strong potential. We summarize the earlier-reported and original results of the THz measurements of neoplasms with different nosology and localization. We pay attention to the origin of contrast between healthy and pathological tissues in the THz spectra and images, and discuss the prospects of THz technology in

THz Pulsed Imaging in Biomedical Applications

“…Many efforts were done in THz technology, improving THz sources and detectors' responses [32][33][34][35][36][37][38], and ensuring devices' flexibility and portability, in recent decades. This has stimulated a wide diffusion of THz systems for spectroscopic and imaging purposes, applicable in various science fields like biology and medicine [39][40][41][42][43][44], gas sensing [45], chemical analysis [46,47], new materials characterization in low-frequency range and non-destructive evaluation of composite materials and constructions [48,49], astronomy [50], microelectronics and security [51][52][53], agri-food industry [54], art conservation [55], etc. Thus, alongside these techniques, TPI has been developed and applied in the field of biomedicine.…”

“…(ii) In addition, the low photon energy is insufficient to cause atoms ionization. (iii) For this reason, it is suitable and attractive for noninvasive biomedical imaging, has a great potentiality and could be applied in vivo real-time studies without causing biological ionizing damage, unlike X-and γ-rays [42,43]. Whereas extremely low frequency electromagnetic fields have been long studied in relation to their possible human health effects, the biological effects of radiofrequency and THz signals have come under scrutiny.…”

“…(v) That is why the strong absorption, due to water molecules (220 cm −1 for pure water at 1 THz and room temperature) [43], limits THz penetrability into the fresh tissues from tens to hundreds microns [42] and the capability of diagnostic only for superficial layers in vivo. (vi) The high sensitivity of water content can be used like an endogenous marker for the differentiation between fresh healthy and pathological tissues [42,43]. (vii) In particular, the time-domain spectroscopy (TDS) and imaging are insensitive to the thermal background and show high signal-to-noise ratio (SNR) [61].…”

Температурная эволюция диэлектрического отклика alpha-лактозы моногидрата в терагерцовом диапазоне частот

“…Среди многочисленных методов контроля молекулярной и кристаллической структуры терагерцовая (ТГц) спектроскопия [1,2] в настоящее время еще не имеет столь же широкого распространения как спектроскопия комбинационного рассеяния света (КРС) и инфракрасная (ИК) спектроскопия, несмотря на ее большой потенциал. К преимуществам данного метода следует отнести низкую ионизирующую способность ТГц излучения и незначительное рассеяние ТГц излучения микрокристаллическими образцами [3,4]. Аппаратура ТГц импульсной спектроскопии не требует применения высокого напряжения или сильных магнитных полей и может быть выполнена в компактном и доступном варианте [5,6].…”

Metallic and dielectric metasurfaces in photoconductive terahertz devices: a review

“…To date, the terahertz (THz) frequency range has found wide applications in many fields ranging from condensed matter physics [1][2][3][4] and material science 5,6 to gas sensing [7][8][9] and pharmaceutical industry 10 as well as various security [11][12][13][14][15][16] and biomedical [17][18][19][20][21][22] applications. All of these require high-sensitive and broadband THz instruments, in particular, efficient operation in real time and at room temperature.…”