Expand this Topic clickable element to expand a topic
Skip to content
Optica Publishing Group
  • 2015 European Conference on Lasers and Electro-Optics - European Quantum Electronics Conference
  • (Optica Publishing Group, 2015),
  • paper CL_P_14

Innovative Fibre Probe for Laser Ablation of Tumour Cells

Not Accessible

Your library or personal account may give you access

Abstract

Laser ablation is emerging as a more effective alternative to the already well consolidated radiofrequency and microwave ablation in the treatment of several solid tumours, and in particular of those developed in the liver. Key for the success of ablation therapies is the control of the temperature induced, so to kill the malignant cells without inducing carbonizations or damages to the surrounding tissue [1]. This paper presents the concept of a new miniaturized all-fibre probe that combines the delivery of high power laser beams and temperature transducers, and provides some results about the characterization of first prototypes. The probe makes use of a double cladding fibre (DCF), in which the inner cladding confines the high-power beam (HPB) for the ablation and the core hosts one or more fibre Bragg gratings (FBG) to setup an integrated temperature sensing system (TSS), as sketched in Fig. 1-left. An additional visible low-power aiming beam (AB) can be injected in the inner cladding as well. Further, to properly tailor the laser emission for different tumour sizes, the lateral surface of the fibre tip is patterned using a CO2 laser to widen the ablation area by enabling side irradiation. The high power laser beam, the aiming beam and the sensing signal are coupled to the probe through a combiner derived from pump combiners with feedthrough used in fibre lasers [2]. Several probes with different surface patterning have been realized and characterized, mainly in terms of irradiation pattern, using a phantom made of agar, a jelly substance whose thermal conductivity is known to be similar to that of the liver, loaded with India-ink to mimic actual light absorption in real operating conditions [3]. The use of such a phantom is essential for the reproducible comparisons between different types of probes, besides for allowing taking pictures of the irradiation profile, although it imposes some limitations in the maximum temperature. An example is shown in Fig. 1-centre for a probe built with a 20/400 DCF and with minimal patterning; the laser source is a 915 nm diode at about 1 W. As not all the prototypal probes were equipped with internal FBG sensors to lower the development costs and thermocouples cannot be inserted into the laser path, the induced temperature has been measured with Bragg grating sensors in bare fibres placed in close contact with the fibre tip, having verified that their reading is minimally affected by the direct laser beam. These measurements have then been related to those from a thermo-camera (TC). To make the two readings comparable (the TC evaluates surface temperatures, FBGs internal ones), we sandwiched the probe and the gratings between two 5 mm thick agar gel slices, switched on the laser and recorded the readings of the FBGs, switched the laser off and quickly removed the upper disc, then took pictures with the TC. An example of the reading from one of the FBG is in Fig. 1-right: in this experiment the temperature induces a shift in the FBG peak wavelength corresponding to an increase of about 18 °C above room temperature, well in agreement with the result found with thermo-camera, demonstrating the effectiveness of the proposed probe.

© 2015 IEEE

PDF Article
More Like This
Laser based microfabrication of microfluidic chips on soda-lime glass for circulating tumour cell capture

Daniel Nieto, Ramiro Couceiro, Rafael Lopez-Lopez, Miguel Abal, and María Teresa Flores-Arias
CM_P_11 The European Conference on Lasers and Electro-Optics (CLEO/Europe) 2015

Discrimination of brain tumours and dysplastic tissues through multimodal fibre-probe spectroscopy

Enrico Baria, Flavio Giordano, Suresh Anand, Anna Maria Buccoliero, Riccardo Cicchi, and Francesco Saverio Pavone
11073_51 European Conference on Biomedical Optics (ECBO) 2019

Fiber-optic technologies for advanced thermo-therapy applied ex vivo to liver tumors

D. Tosi, G. Perrone, A. Vallan, A. Braglia, Y. Liu, E. G. Macchi, G. Braschi, M. Gallati, A. Cigada, S. Poeggel, D. B. Duraibabu, G. Leen, and E. Lewis
95370S European Conference on Biomedical Optics (ECBO) 2015

Select as filters


Select Topics Cancel
© Copyright 2024 | Optica Publishing Group. All Rights Reserved