FREE SHIPPING over $40
OVER 10000 FIVE-STAR REVIEWS
5% OFF ALL SUBSCRIPTIONS
100% HAPPINESS GUARANTEE
Analyze Diet
0
Veterinary ophthalmology2014; 17 Suppl 1(0 0); 107-116; doi: 10.1111/vop.12166

The location of sites and effect of semiconductor diode trans-scleral cyclophotocoagulation on the buphthalmic equine globe.

Abstract: To determine appropriate location and energy settings for trans-scleral cyclophotocoagulation (TSCPC) for buphthalmic equine globes. Methods: Eleven horses with a buphthalmic eye blinded by glaucoma presented for enucleation. Methods: Globe and corneal dimensions were measured via ultrasonography and calipers, and TSCPC was performed under general anesthesia immediately prior to enucleation. Part 1: In nine globes, sixty sites were lasered 4 mm posterior to the limbus in the dorsotemporal and ventrotemporal quadrants at settings of 1500 milliwatts and 1500 ms. Globes were processed and sectioned sagitally over the temporal aspect in two blocks, each with five histologic sections examined by light microscopy. A digital imaging system was used to determine the location and length of the pars plicata on one slide from each block. Part 2: Based on results in Part 1, two globes were measured and lasered using the same time and energy settings at the following distances posterior to the limbus: 8 mm dorsally, 6 mm dorsotemporally, 5 mm ventrotemporally, and 5 mm ventrally. Results: Globe and corneal dimensions exceeded normal values in all globes. Part 1: In all nine globes, photocoagulation affected the anterior ciliary processes and iris base and in 8/9 coagulation of the pectinate ligaments was noted. Part 2: In both globes, coagulation was confined to the pars plicata. Conclusions: The previously recommended TSCPC sites are located too far anteriorly for a buphthalmic globe. Buphthalmic equine globes should have TSCPC performed at the following distances posterior to the limbus: 6-8 mm dorsally, 5-6 mm dorsotemporally, 4-5 mm ventrotemporally, and 4-5 mm ventrally.
© 2014 American College of Veterinary Ophthalmologists.
Get Full Text
Publication Date: 2014-04-03 PubMed ID: 24697980PubMed Central: PMC4082759DOI: 10.1111/vop.12166Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
LinkedInCopy
  • Journal Article
  • Research Support
  • N.I.H.
  • Extramural

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This research paper investigates the ideal location and energy settings for a laser procedure called trans-scleral cyclophotocoagulation (TSCPC) on horses with a buphthalmic eye condition caused by glaucoma. The author concluded that previous TSCPC sites were too far forward for a buphthalmic globe of a horse’s eye and suggested new locations for the procedure.

Research Methodology

  • The researchers studied 11 horses with glaucoma-induced buphthalmic eyes that were presented for eye removal (enucleation).
  • The dimensions of the eye globe and cornea were measured using ultrasonography and calipers.
  • TSCPC was performed on these horses under general anesthesia just before the enucleation procedure.
  • In the first part of the experiment, nine eyes were laser treated at sixty sites, 4mm behind the limbus in the dorsotemporal and ventrotemporal quadrants at settings of 1500 milliwatts and 1500 ms.
  • The globes were processed and cut sagittaly along the temporal aspect, then examined under a microscope. A digital imaging system determined the location and length of the pars plicata.
  • In the second part of the experiment, based on the previous results, two globes were measured and TSCPC was performed at differing distances posterior to the limbus with the same time and energy settings.

Results of the Research

  • They saw that all the globe and corneal dimensions exceeded regular values in all globes.
  • In all nine globes from the first part of the experiment, the laser treatment affected the ciliary processes at the front and the base of the iris. In eight out of nine cases, coagulation of the pectinate ligaments was observed.
  • In the second part of the experiment, in both globes, coagulation was confined to the pars plicata.

Conclusions of the Study

  • The research concluded that the previously recommended locations for TSCPC treatment were too far anteriorly for a buphthalmic globe in the cases of glaucoma in horses.
  • The authors suggest that TSCPC treatment for buphthalmic equine globes be performed at the following distances posterior to the limbus: 6-8 mm dorsally, 5-6 mm dorsotemporally, 4-5 mm ventrotemporally, and 4-5 mm ventrally.

Cite This Article

APA
Gemensky-Metzler AJ, Wilkie DA, Weisbrode SE, Kuhn SE. (2014). The location of sites and effect of semiconductor diode trans-scleral cyclophotocoagulation on the buphthalmic equine globe. Vet Ophthalmol, 17 Suppl 1(0 0), 107-116. https://doi.org/10.1111/vop.12166

Publication

Veterinary ophthalmology
ISSN: 1463-5224
NlmUniqueID: 100887377
Country: England
Language: English
Volume: 17 Suppl 1
Issue: 0 0
Pages: 107-116

Researcher Affiliations

Gemensky-Metzler, Anne J
  • Department of Veterinary Clinical Sciences, The Ohio State University College of Veterinary Medicine, Columbus, OH, 43210, USA.
Wilkie, David A
    Weisbrode, Steven E
      Kuhn, Sonia E

        MeSH Terms

        • Animals
        • Female
        • Horse Diseases / pathology
        • Horse Diseases / surgery
        • Horses
        • Hydrophthalmos / pathology
        • Hydrophthalmos / surgery
        • Hydrophthalmos / veterinary
        • Laser Coagulation / instrumentation
        • Laser Coagulation / methods
        • Laser Coagulation / veterinary
        • Lasers, Semiconductor
        • Male

        Grant Funding

        • P30 CA016058 / NCI NIH HHS

        References

        This article includes 25 references
        1. Curto EM, Gemensky-Metzler AJ, Chandler HL, Wilkie DA. Equine glaucoma: a histopathologic retrospective study (1999-2012). Vet Ophthalmol 2013.
          pubmed: 23859597
        2. Annear MJ, Wilkie DA, Gemensky-Metzler AJ. Semiconductor diode laser transscleral cyclophotocoagulation for the treatment of glaucoma in horses: a retrospective study of 42 eyes. Vet Ophthalmol 2010;13(3):204–9.
          pubmed: 20500721
        3. Cullen CL, Grahn BH. Equine glaucoma: a retrospective study of 13 cases presented at the Western College of Veterinary Medicine from 1992 to 1999. Can Vet J 2000;41(6):470–80.
          pmc: PMC1476223pubmed: 10857031
        4. Miller TR, Brooks DE, Gelatt KN, King TC, Smith PJ, Sapienza JS. Equine glaucoma: clinical findings and response to treatment in 14 horses. Vet & Comp Ophthalmol 1995;5(3):170–82.
        5. van der Woerdt A, Gilger B, Wilkie DA, Strauch SM. Effect of auriculopalpebral nerve block and intravenous administration of xylazine on intraocular pressure and corneal thickness in horses. Am J Vet Res 1995;56(2):155–8.
          pubmed: 7717576
        6. Miller PE, Pickett JP, Majors LJ. Evaluation of two applantation tonometers in horses. Am J Vet Res 1990;51(6):935–7.
          pubmed: 2368953
        7. Dziezyc J, Millichamp NJ, Smith WB. Comparison of applanatin tonometers in dogs and horses. JAVMA 1992;201(3):430–3.
          pubmed: 1506245
        8. Willis AM, Robbin TE, Hoshaw-Woodard S, Wilkie DA, Schmall ML. Effect of topical administration of 2% dorzlamide hydrochloride or 2% dorzlamide hydrochloride-0.5% timolol maleate on intraocular pressure in clinically normal horses. Am J Vet Res 2001;62(5):709–13.
          pubmed: 11341390
        9. Gelatt JK, MacKay EO. Changes in intraocular pressure associated with topical dorzolamide and oral methazolamide in glaucomatous dogs. Vet Ophtho 2001;4:61–7.
          pubmed: 11397321
        10. Ghosh S, Manvikar S, Ray-Chaudhuri N, Birch M. Efficacy of transscleral diode laser cyclophotocoagulation in patients with good visual acuity. Eur J Ophthalmol 2013:0.
          pubmed: 24242221
        11. Cook CS, Davidson MG, Brinkman M, Priehs D, Abrams KL, Nasisse MP. Diode laser transscleral cyclophotocoagulation for the treatment of glaucoma in dogs: results of six and twelve month follow-up. Vet & Comp Ophtho 1997;7(3):148–54.
        12. Hardman C, Stanley RG. Diode laser transscleral cyclophotocoagulation for the treatment of primary glaucoma in 18 dogs: a retrospective study. Vet Ophthalmol 2001;4(3):209–15.
          pubmed: 11722786
        13. Whigham HM, Brooks DE, Andrew SE, Gelatt KN, Strubbe DT, Biros DJ. Treatment of equine glaucoma by transscleral neodymium:yttrium aluminum garnet laser cyclophotocoagulation: a retrospective study of 23 eyes of 16 horses. Vet Ophthalmol 1999;2(4):243–50.
          pubmed: 11397272
        14. Blasini M, Simmons R, Shields MB. Early tissue response to transscleral neodymium: YAG cyclophotocoagulation. Invest Ophthalmol Vis Sci 1990;31(6):1114–8.
          pubmed: 2354913
        15. Nasisse MP, Davidson MG, MacLachlan NJ, Corbett W, Tate LP, Newman HC. Neodymium:yttrium, aluminum, and garnet laser energy delivered transsclerally to the ciliary body of dogs. Am J Vet Res 1988;49(11):1972–8.
          pubmed: 3247921
        16. Nasisse MP, McGahan MC, Shields MB, Echelman D, Fleisher LN. Inflammatory effects of continuous-wave neodymium: yttrium aluminum garnet laser cyclophotocoagulation. Invest Ophthalmol Vis Sci 1992;33(7):2216–23.
          pubmed: 1318869
        17. Cavens VJ, Gemensky-Metzler AJ, Wilkie DA, Weisbrode SE, Lehman AM. The long-term effects of semiconductor diode laser transscleral cyclophotocoagulation on the normal equine eye and intraocular pressure(a). Vet Ophthalmol 2012;15(6):369–75.
          pubmed: 22288723
        18. Miller TL, Willis AM, Wilkie DA, Hoshaw-Woodard S, Stanley JR. Description of ciliary body anatomy and identification of sites for transscleral cyclophotocoagulation in the equine eye. Vet Ophthalmol 2001;4(3):183–90.
          pubmed: 11722782
        19. Morreale RJ, Wilkie DA, Gemensky-Metzler AJ, Weisbrode SE, Willis MA. Histologic effect of semiconductor diode laser transscleral cyclophotocoagulation on the normal equine eye. Vet Ophthalmol 2007;10(2):84–92.
          pubmed: 17324163
        20. Rogers M, Cartee RE, Miller W, Ibrahim AK. Evaluation of the extirpated equine eye using B-mode ultrasonography. Vet Radiol 1986;27(1):24–9.
        21. Grinninger P, Skalicky M, Nell B. Evaluation of healthy equine eyes by use of retinoscopy, keratometry, and ultrasonographic biometry. Am J Vet Res 2010;71(6):677–81.
          pubmed: 20513184
        22. Nasisse MP, Davidson MG, English RV, Jamieson V, Harling DE, Tate LP. Treatment of glaucoma by use of transscleral neodymium:yttrium aluminum garnet laser cyclocoagulation in dogs. J Am Vet Med Assoc 1990;197(3):350–4.
          pubmed: 2391270
        23. Nadelstein B, Wilcock BP, Cook CS, Davidson MG. Clinical and histopatholigic effects of diode laser transscleral cyclophotocoagulation in the normal canine eye. Vet & Comp Ophtho 1997;7(3):155–62.
        24. Schlote T, Beck J, Rohrbach JM, Funk RH. Alteration of the vascular supply in the rabbit ciliary body by transscleral diode laser cyclophotocoagulation. Graefe’s archive for clinical and experimental ophthalmology = Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie 2001;239(1):53–8.
          pubmed: 11271463
        25. Brancato R, Leoni G, Trabucchi G, Cappellini A. Histopathology of continuous wave neodymium: yttrium aluminum garnet and diode laser contact transscleral lesions in rabbit ciliary body. A comparative study. Invest Ophthalmol Vis Sci 1991;32(5):1586–92.
          pubmed: 2016140

        Citations

        This article has been cited 1 times.
        1. Slenter IJM, Hermans H, Ensink JM, Willems DS, Veraa S, Grinwis GCM, Boevé MH. Clinical, ultrasonographic, and histopathologic findings in seven horses with Descemet's membrane detachment: A case series. Vet Ophthalmol 2020 Jan;23(1):181-189.
          doi: 10.1111/vop.12710pubmed: 31544302google scholar: lookup
        Subscribe to our newsletter
        Join 99,727 horse owners like you who receive our email updates on horse health and nutrition.