Selective transscleral cyclophotocoagulation: mathematical modeling for evaluating the efficacy-safety balance in neovascular glaucoma

Authors

DOI:

https://doi.org/10.31288/Ukr.j.ophthalmol.20264413

Keywords:

neovascular glaucoma, transscleral cyclophotocoagulation, mathematical modeling, temperature, Thermal Selectivity Index, intraocular pressure

Abstract

Purpose. To quantitatively evaluate the efficacy-safety balance of transscleral cyclophotocoagulation (TSCPC) through a mathematical modeling-based analysis of thermal tissue response in the ciliary body, and to determine the laser exposure parameters for achieving a selective coagulation effect in neovascular glaucoma (NVG).

Material and Methods. A model of heat transfer in the ciliary body was developed using the Pennes bioheat transfer equation. Continuous Wave (CW) TSCPC and MicroPulse TSCPC at 1 W and 2W for a single 2-s application and a series of 2-s applications were subjected to analysis. The following parameters were determined: maximum temperature (Tmax), time to reach 50 °C (t50), time in the temperature range 50–60 °C (t50-60), and time in the temperature range above 60 °C (t(>60)). Integral thermal indices including the Therapeutic Exposure Index (TEI), Destructive Exposure Index (DEI), and Thermal Selectivity Index (TSI), and Safety Margin were calculated.

Results. A single 2-s CW-TSCPC application at 1 W enabled achieving the coagulation temperature threshold (Tmax = 50.8 °C; t50 = 1.44 s) without a transition to the destructive temperature range (> 60 °C), whereas that at 2 W was accompanied by tissue overheating (Tmax = 61.8 °C; t50 = 0.4 s). A series of 2-s CW laser applications at 1 W enabled accumulation of the heat dose within the therapeutic window (t50–60 = 17.1 s; DEI = 0), whereas that at 2 W resulted in large t(>60) values (t(>60) = 39.7 s; DEI = 0.67). MicroPulse TSCPC did not result in reaching the coagulation threshold (Tmax ≤ 49 °C). The integral indices confirmed the optimal efficacy–safety balance for a CW-TSCPC application at 1 W.

Conclusion. The 60 °C temperature threshold determines the transition from coagulative to destructive tissue injury. Therefore, CW-TSCPC at 1 W provides an optimal efficacy-safety balance due to a selective coagulative effect, and can be considered a pathophysiologically justified strategy for optimizing TSCPC parameters in NVG.

Author Biographies

  • O. V. Guzun, Filatov Institute of Eye Diseases and Tissue Therapy of the National Academy of Medical Sciences of Ukraine

    Olga V. Guzun, Cand Sc (Med), Senior Researcher, SI “The Filatov Institute of Eye Diseases and Tissue Therapy of the National Academy of Medical Sciences of Ukraine”, Odesa, Ukraine

  • O. S. Zadorozhnyy, Filatov Institute of Eye Diseases and Tissue Therapy of the National Academy of Medical Sciences of Ukraine

    Oleg S. Zadorozhnyy, Dr Sc (Med), Senior Researcher and Deputy Director for Scientific Work, SI “The Filatov Institute of Eye Diseases and Tissue Therapy of the National Academy of Medical Sciences of Ukraine”, Odesa, Ukraine

  • P. I. Osadchuk, Odesa National University of Technology

    Petr Osadchuk, Dr Sc (Engineering), Prof. and Chair, Department for Electromechanics and Mechatronics, Institute of Automation and Robotics, Odesa National University of Technology, Odesa, Ukraine

  • V. V. Vychuzhanin, Odesа Polytechnic National University

    Vladimir Vychuzhanin, Dr Sc (Engineering), Prof. and Chair, Department of Information Technologies, Odesa Polytechnic National University, Odesa, Ukraine

  • A. D. Khomenko, Odesa National University of Technology

    Andrii Khomenko, Lecturer, Department for Electromechanics and Mechatronics, Institute of Automation and Robotics, Odesa National University of Technology, Odesa, Ukraine

  • A. R. Korol, Filatov Institute of Eye Diseases and Tissue Therapy of the National Academy of Medical Sciences of Ukraine

    Andrii Korol, Dr Sc (Med), Prof., Senior Researcher and Deputy Director for Innovation and External Relations, SI “The Filatov Institute of Eye Diseases and Tissue Therapy of the National Academy of Medical Sciences of Ukraine”, Odesa, Ukraine; 

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Published

2026-08-31

Issue

No. 4 (2026): Ukrainian Journal of Ophthalmology

Section

Clinical Ophthalmology

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Copyright (c) 2026 Guzun O.V., Zadorozhnyy O. S., Osadchuk P. I., Vychuzhanin V. V., Khomenko A. D., Korol A. R.

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How to Cite

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Selective transscleral cyclophotocoagulation: mathematical modeling for evaluating the efficacy-safety balance in neovascular glaucoma. Ukr. j. ophthalmol. [Internet]. 2026 Aug. 31 [cited 2026 Sep. 1];(4):4-13. Available from: https://ua.ozhurnal.com/index.php/files/article/view/986

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