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Applicator for RF Thermokeratoplasty: Feasibility Study Using Theoretical Modeling and Ex Vivo Experiments

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Abstract

Radiofrequency (RF) thermokeratoplasty uses RF currents to alter the curvature of the cornea by means of thermal lesions. An RF applicator which combined a microkeratome suction ring and a circular electrode was designed with the aim of creating circular thermal lesions in a predictable, uniform and safe way. An experimental study was conducted on ex vivo porcine eyes. A theoretical model was also designed. The experimental results showed a lesion depth of 34.2 ± 11.0% of corneal thickness at a constant voltage of 50 V up to roll-off (1000 Ω of impedance). With a voltage of 30 V for 30 s the mean depth was 36.8 ± 8.1%. The progress of electrical impedance throughout heating and lesion dimensions were used to compare the experimental and theoretical results. Both the impedance evolution and lesion dimensions obtained from the theoretical model showed good agreement with the experimental findings. The findings suggest that the new applicator could be a suitable option for creating uniform circular thermal lesions.

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Acknowledgments

This work received financial support from the Spanish “Plan Nacional de I+D+I del Ministerio de Ciencia e Innovación” Grant No. TEC2008-01369/TEC and FEDER Project MTM2010-14909. The translation of this paper was partially funded by the Universitat Politècnica de València, Spain.

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Authors and Affiliations

  1. Instituto Universitario de Matemática Pura y Aplicada, Universitat Politècnica de València, Valencia, Spain

    Macarena Trujillo

  2. Neptury Technologies, Almassora, Spain

    Vicente Ribera

  3. Department of Surgery, Hospital del Mar, Barcelona, Spain

    Rita Quesada

  4. Biomedical Synergy, Electronic Engineering Department, Universitat Politècnica de València, Camino de Vera, 46022, Valencia, Spain

    Enrique Berjano

Authors
  1. Macarena Trujillo
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  2. Vicente Ribera
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  3. Rita Quesada
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  4. Enrique Berjano
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Correspondence to Enrique Berjano.

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Associate Editor Gerald Saidel oversaw the review of this article.

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Trujillo, M., Ribera, V., Quesada, R. et al. Applicator for RF Thermokeratoplasty: Feasibility Study Using Theoretical Modeling and Ex Vivo Experiments. Ann Biomed Eng 40, 1182–1191 (2012). https://doi.org/10.1007/s10439-011-0492-1

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  • DOI: https://doi.org/10.1007/s10439-011-0492-1

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