A Problem of THz Endoscopy of Hard-to-Access Tissues

Kirill I. Zaytsev orcid (Login required)
Prokhorov General Physics Institute of the Russian Academy of Sciences, Moscow, Russian Federation

Gleb M. Katyba orcid
Osipyan Institute of Solid State Physics of the Russian Academy of Sciences, Chernogolovka, Russian Federation

Nikita V. Chernomyrdin orcid
Prokhorov General Physics Institute of the Russian Academy of Sciences, Moscow, Russian Federation

Kirill B. Dolganov
Prokhorov General Physics Institute of the Russian Academy of Sciences, Moscow, Russian Federation

Irina N. Dolganova orcid
Osipyan Institute of Solid State Physics of the Russian Academy of Sciences, Chernogolovka, Russian Federation

Sergei V. Garnov orcid
Prokhorov General Physics Institute of the Russian Academy of Sciences, Moscow, Russian Federation

Vladimir N. Kurlov orcid
Osipyan Institute of Solid State Physics of the Russian Academy of Sciences, Chernogolovka, Russian Federation


Paper #9378 received 16 Oct 2025; revised manuscript received 31 Dec 2025; accepted for publication 31 Dec 2025; published online 10 Apr 2026.

DOI: 10.18287/JBPE26.12.020302

Abstract

Despite terahertz (THz) technologies offer a number of applications in medical diagnosis and therapy, their translation into clinics is hampered by the lack of THz endoscopes capable of sensing THz response of hard-to-access tissues. In this paper, we focus on recent attempts to mitigate this difficulty. We consider the two existing principles of THz endoscopy. The first uses the fiber-coupled THz photoconductive antennas (PCAs) for the THz generation and detection in close proximity to an object. The second relies on the THz optical fibers to deliver THz waves to an analyte and then to detect the reflected THz signal. Most recent developments in the area of THz fiber optics pave the way to solve the challenging problem of THz endoscopy. Among them, we emphasize the THz fibers, fiber bundles, waveguides, and endoscopes developed by our research group based on the sapphire shaped crystals obtained by the edge-defined film-fed growth (EFG) technique.

Keywords

THz technology; THz fiber optics; THz endoscopy; THz medical diagnosis; THz spectroscopy and imaging

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