CC BY
16B-I-25
Multimodal sapphire medical instruments for laser exposure, diagnosis and treatment of tissues
I.N. Dolganova1'2, A.K. Zotov1, I.A. Shikunova1, D.A. Varvina3, P.A. Karalkin45, K.I. Zaytsev26,
V.V. Tuchin7, and V.N. Kurlov1
1-Institute of Solid State Physics of the Russian Academy of Sciences, Russia
2- Institute for Regenerative Medicine, Sechenov University, Russia 3- International School "Medicine of the Future", Sechenov University, Russia 4- Institute for Cluster Oncology, Sechenov University, Russia 5- Hertsen Moscow Oncology Research Institute, National Medical Research Radiological Centre, Russia 6- Prokhorov General Physics Institute of the Russian Academy of Sciences, Russia 7- Science Medical Center, Saratov State University, Russia
in. dolganova@gmail.com
Sapphire possesses a combination of properties, which make it a favourable material platform for medical instruments [1,2]. Among them are biocompatibility, high chemical and thermal stability, transparency in visible and partly infrared (IR) ranges, and high hardness. Application of techniques of sapphire growth from melt, such as edge-defined film-fed growth (EFG), helps to fabricate sapphire crystals with complex shape without essential mechanical processing. EFG allows making capillary needles, fibers, waveguides, and ribbons with internal thin channels, which demonstrate high volume and surface quality with low concentration of defects [3]. Such sapphire shaped crystals can form a basis for multimodal medical instruments, since they can perform different functions. This is mainly due to the ability of accommodating optical fibers inside their capillary channels and the transparency of sapphire for visible and IR radiation. Capillary needles can be used for interstitial laser and photodynamic therapy, as well as for diagnosis of internal tissues, when the internal fiber is connected with a laser source or a spectrometer [4,5]. Having small outer diameter near 1 mm, they provide minimal invasiveness of medical treatment. Their tips can possess various forms, enabling different radiation patterns, from diffused to focused one. Sapphire scalpels with one, two, or three channels produced from thin ribbons by additional mechanical and chemical sharpening combine functions of tissue dissection, local diagnosis, and coagulation [1,7]. Diagnostic resolution of such scalpels can reach 2 mm, when the cutting-edge rounding can be as sharp as 100 nm. Sapphire neuroprobes can be used for intraoperative fluorescence diagnosis of brain tissues and aspiration, when having closed and open channels in its body. They also can be used for additional coagulation of tissues. Finally, sapphire cryoprobes can open novel abilities of cryosurgery, since they demonstrate promising feature of monitoring and controlling the freezing depth during application using optical methods, such as diffuse reflection or terahertz spectroscopy, or even optical coherence tomography [8]. In addition, such probes provide faster tissue freezing comparing to metal cryoapplicators. In this talk, we summarize the recent developments and studies of sapphire medical instruments, discuss their advantages and drawbacks, as well as further applications and clinical studies.
This work was supported by the Russian Science Foundation (RSF), research project # 19-79-10212.
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