Miniaturized fiber dosimeter of medical ionizing radiations on a narrow optical fiber

Miguel Angel Suarez (1) , Tony Lim (2) , Louise Robillot (1) , Valentin Maillot (1) , Thomas Lihoreau (3) , Patrick Bontemps (2) , Lionel Pazart (4) , Thierry Grosjean (1)

1 FEMTO-ST - Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174)
2 Service de Radiothérapie [CHRU Besançon]
3 RIGHT - Interactions hôte-greffon-tumeur, ingénierie cellulaire et génique - UFC (UMR INSERM 1098)
4 Inserm CIC 1431 - Centre d'Investigation Clinique de Besançon

Fiber dosimeters have recently drawn much interest for measuring in vivo and in real time the dose of medical radiations. This paper presents the first miniaturized fiber dosimeter integrated at the end of a narrow 125 μm outer diameter optical fiber. Miniaturization is rendered possible by exploiting the concept of a leaky wave optical antenna for interfacing the scintillators and the fiber and by taking advantage of the low propagation loss of narrow silica fibers and high detection yield of single-pixel photon counters. Upon irradiation at 6 MV in air, our fiber probe leads to a linear detection response with a signal-to-noise ratio as high as 195. Although implemented with inorganic scintillators and fiber, our miniaturized fiber probe induces minimum screening effects on ionizing radiations over a negligible area (0.153 mm2). Our nano-optically driven approach may thus result in ultra-compact fiber dosimeters of negligible footprint in the radiotherapeutic processes, even with non-water equivalent fibers and scintillators. This opens new opportunities for a large panel of therapies relying on ionizing radiations (photons or charged particles).

Domaines: Optique [physics.optics]

Miguel Angel Suarez, Tony Lim, Louise Robillot, Valentin Maillot, Thomas Lihoreau, et al.. Miniaturized fiber dosimeter of medical ionizing radiations on a narrow optical fiber. Optics Express, 2019, 27 (24), pp.35588 - 35599. ⟨hal-02376867⟩