Inside-the-body light delivery system using endovascular therapy-based light illumination technology br

Background Light-based therapies are promising for treating diseases including cancer, hereditary conditions, and protein-related disorders. However, systems, methods, and devices that deliver light deep inside the body are limited. This study aimed to develop an endovascular therapy-based light illumination technology (ET-BLIT), capable of pro-viding deep light irradiation within the body.Methods The ET-BLIT system consists of a catheter with a single lumen as a guidewire and diffuser, with a transparent section at the distal end for thermocouple head attachment. The optical light diffuser alters the emission direction laterally, according to the optical fibre's nose-shape angle. If necessary, after delivering the catheter to the target position in the ves-sel, the diffuser is inserted into the catheter and placed in the transparent section in the direction of the target lesion.Findings ET-BLIT was tested in an animal model. The 690-nm near-infrared (NIR) light penetrated the walls of blood vessels to reach the liver and kidneys without causing temperature increase, vessel damage, or blood compo-nent alterations. NIR light transmittance from the diffuser to the detector within the organ or vessel was approxi-mately 30% and 65% for the renal and hepatic arteries, respectively.Interpretation ET-BLIT can be potentially used in clinical photo-based medicine, as a far-out technology. ET-BLIT uses a familiar method that can access the whole body, as the basic procedure is comparable to that of endovascular therapy in terms of sequence and technique. Therefore, the use of the ET-BLIT system is promising for many light -based therapies that are currently in the research phase.Funding Supported by Programme for Developing Next-generation Researchers (Japan Science and Technology Agency); JSPS KAKENHI (18K15923, 21K07217); JST-CREST (JPMJCR19H2); JST-FOREST-Souhatsu (JPMJFR2017); The Uehara Memorial Foundation; Yasuda Memorial Medical Foundation; Mochida Memorial Foundation for Medical and Pharmaceutical Research; Takeda Science Foundation; The Japan Health Foundation; Takahashi Industrial and Eco-nomic Research Foundation; AICHI Health Promotion Foundation; and Princess Takamatsu Cancer Research Fund. Copyright (c) 2022 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)

Automated summary

This study developed an endovascular therapy-based light illumination technology capable of providing deep light irradiation within the body, which was tested in an animal model and showed promising results for potential clinical applications in photo-based medicine.