N 4 (189) 2024. P. 13–18

HISTOPATHOLOGICAL CHANGES IN RABBIT EYES AFTER TRANSSCLERAL DIODE CYCLOPHOTOCOAGULATION

O. V. Guzun, O. S. Zadorozhnyy, P. P. Chechyn, O. V. Artеmov, Wael Chargui, A. R. Korol

State Institution “The Filatov Institute of Eye Diseases and Tissue Therapy of the National Academy of Medical Sciences of Ukraine”, Odesa, Ukraine

DOI 10.32782/2226-2008-2024-4-2

Currently, the issue of choosing the energy characteristics of laser radiation to ensure the optimal effect on the structures of the ciliary body during diode (810 nm) transscleral cyclophotocoagulation (TSC CPC) remains debatable.

The research purpose is to determine histopathological changes occurring in the sclera and ciliary body after transscleral diode cyclophotocoagulation with different energy characteristics of laser radiation in the experiment.

Material and methods. The study was conducted on the eyes of 2 rabbits (4 eyes). TSC CPC was carried out using a diode laser with a wavelength of 810 nm and a contact fibre-optic G-probe. Two energy regimes were used: 1 – power 2000 mW, exposure 1.5 sec (3 J energy per pulse) and 2 – power 1000 mW, exposure 1.5 sec (1.5 J energy per pulse). The analysis of the experimental studies’ results included light microscopy of histological sections on the 10th day after TSC CPC.

Results. After 2000 mW/1.5 sec TSC CPC (energy 3 J) per pulse, pronounced destruction of ciliary processes and underlying stroma of the ciliary body, as well as pigmented and non-pigmented ciliary epithelium, was observed. The coagulation necrosis of collagen fibres of the sclera was detected. After 1000 mW/1.5 sec TSC CPC (energy 1.5 J) per pulse, the destruction of the pigmented and non-pigmented epithelium of the ciliary body was observed, with less disorganisation of the stroma of the ciliary body. The sclera was not affected when the energy was reduced.

Conclusions. Diode TSC CPC (810 nm) with a laser radiation power of 1000 mW (exposure 1.5 seс) is a more selective form of cyclophotocoagulation, which leads to less destruction of the ciliary body and sclera and at the same time ensures damage to the epithelium of the ciliary body, compared to the use of laser radiation with 2000 mW power.

Key words: diode laser, transcleral cyclophotocoagulation, histopathology, necrosis.

REFERENCES

  1. Aquino MC, Barton K, Tan AM, et al. Micropulse versus continuous wave transscleral diode cyclophotocoagulation in refractory glaucoma: a randomized exploratory study. Clin Exp Ophthalmol. 2015; 43(1): 40–6. doi: 10.1111/ceo.12360.
  2. Dotson AD, Fingert JH, Boese EA. Unsuccessful transscleral cyclophotocoagulation in oculocutaneous albinism. Am J Ophthalmol Case Rep. 2024; 34: 102020. doi: 10.1016/j.ajoc.2024.102020.
  3. Johansyah CAP, Bambang L. A Systematic Review of Cyclophotocoagulation Techniques: Continuous Wave Versus Micropulse for Glaucoma Treatment. Beyoglu Eye J. 2024; 9(1): 1–7. doi: 10.14744/bej.2024.47123.
  4. Zemba M, Dumitrescu OM, Vaida F, et al. Micropulse vs. continuous wave transscleral cyclophotocoagulation in neovascular glaucoma. Exp Ther Med. 2022; 23(4): 278. doi: 10.3892/etm.2022.11207.
  5. Barac R, Vuzitas M, Balta F. Choroidal thickness increase after micropulse transscleral cyclophotocoagulation. Rom J Ophthalmol. 2018; 62(2): 144–148. PMID: 30206558; PMCID: PMC6117517.
  6. Nemoto H, Honjo M, Okamoto M, Sugimoto K, Aihara M. Potential Mechanisms of Intraocular Pressure Reduction by Micropulse Transscleral Cyclophotocoagulation in Rabbit Eyes. Invest Ophthalmol Vis Sci. 2022; 63(6): 3. doi: 10.1167/ iovs.63.6.3.
  7. Chechin PP, Vit VV, Guzun OV. Histomorphologic changes after contact transscleral Nd: YAG laser cyclophotocoagulation with scleral compression. Ophthalmol. (in Ukrainian). 2018; 2: 41–4. https://doi.org/10.31288/oftalmolzh/2018/2/4144.
  8. Guzun O, Zadorozhnyy O,Artyomov А, Elagina V. Histological Changes in the Intraocular Structures of an Enucleated Eye with Uveal Melanoma and Secondary Painful Neovascular Glaucoma after Palliative Diode Transscleral Cyclophotocoagulation (Clinical Case). Vostochnaja Evropa. 2021; 3(11): 368–377. https://doi.org/10.34883/PI.2021.11.3.037.
  9. Lanzagorta-Aresti A, Montolío-Marzo S, Davó-Cabrera JM, Piá-Ludeña JV. Transscleral versus endoscopic cyclophotocoagulation outcomes for refractory glaucoma. European Journal of Ophthalmology. 2021; 31(3): 1107–1112. doi: 10.1177/1120672120914230.
  10. Tsujisawa T, Ishikawa H, Uga S, et al. Morphological Changes and Potential Mechanisms of Intraocular Pressure Reduction after Micropulse Transscleral Cyclophotocoagulation in Rabbits. Ophthalmic Res. 2022; 65(5): 595–602. doi: 10.1159/000510596.
  11. Williams IM, Neerukonda VK, Stagner AM. The Histopathology of Two Eyes Enucleated after Continuous Transscleral and Micropulse Transscleral Cyclophotocoagulation for Refractory Secondary Glaucoma. Ocul Oncol Pathol. 2022; 8(2): 93–99. doi: 10.1159/000521739.
  12. Moussa K, Feinstein M, Pekmezci M, et al. Histologic Changes Following Continuous Wave and Micropulse Transscleral Cyclophotocoagulation: A Randomized Comparative Study. Transl Vis Sci Technol. 2020; 9(5): 22. doi: 10.1167/tvst.9.5.22.
  13. Schlote T, Beck J, Rohrbach JM, Funk RH. Alteration of the vascular supply in the rabbit ciliary body by transscleral diode laser cyclophotocoagulation. Graefes Arch Clin Exp Ophthalmol. 2001; 239(1): 53–8. doi: 10.1007/pl00007898.
  14. Souissi S, Le Mer Y, Metge F, Portmann A, Baudouin C, Labbé A, Hamard P. An update on continuous-wave cyclophotocoagulation (CW-CPC) and micropulse transscleral laser treatment (MP-TLT) for adult and paediatric refractory glaucoma. Acta Ophthalmol. 2021; 99(5): e621–e653. doi: 10.1111/aos.14661.
  15. Cakir I, Altan C, Yalcinkaya G, et al. Anterior chamber laser flare photometry after diode laser cyclophotocoagulation. Photodiagnosis Photodyn Ther. 2022; 37: 102580. doi: 10.1016/j.pdpdt.2021.102580.
  16. Ahn SM, Choi M, Kim SW, Kim YY. Changes After a Month Following Micropulse Cyclophotocoagulation in Normal Porcine Eyes. Transl Vis Sci Technol. 2021; 10(13): 11. doi: 10.1167/tvst.10.13.11.
  17. Kelada M, Normando EM, Cordeiro FM, et al. Cyclodiode vs micropulse transscleral laser treatment. Eye (Lond). 2024; 38(8): 1477–1484. doi: 10.1038/s41433-024-02929-1.
  18. Reitsamer HA, Kiel JW. Relationship between ciliary blood flow and aqueous production in rabbits. Invest Ophthalmol Vis Sci. 2003; 44(9): 3967–71.\
  19. Zarzecki M, Obuchowska I, Ustymowicz A, Konopińska J. Glaucoma Surgery and Ocular Blood Flow in Colour Doppler Imaging: Is There a Link? Clin Ophthalmol. 2024; 18: 49–60. doi: 10.2147/OPTH.S441805.
View article PDF