Advertisement

193-nm Excimer laser sclerostomy using a modified open mask delivery system in rhesus monkeys with experimental glaucoma

  • B. D. S. Allan
  • P. P. van Saarloos
  • R. L. Cooper
  • E. J. Keogh
  • L. J. Constable
Clinical Investigations

Abstract

Excimer laser sclerostomy is a new glaucoma filtration procedure in which the argon fluoride excimer laser at 193 nm is delivered ab externo through a modified open mask system incorporating an en-face air jet to dry the target area and preserve hemostasis during ablation and a conjunctival plication mechanism, which allows the conjunctival and scleral wounds created by through-and-through ablation to separate once the mask is removed. No preparatory dissection of the conjunctiva is required. Five 200-μm and five 500-gmm sclerostomies were formed by ablation at a pulse repetition rate of 20 Hz and a fluence per pulse of 400 mJ/cm2 in fellow eyes of five rhesus monkeys with experimental glaucoma. Overall, seven of the ten eyes attained a functional result, with intraocular pressures remaining below 21 mmHg for 6 ± 1 days and rising to the pre-operative level after 10 ± 3 days without adjunctive antifibroblast medication. The duration of filtration for 200-μm and 500-μm sclerostomies was similar, and parallels that previously observed for posterior lip sclerostomy in the same animal model. The three eyes with no functional result all had incorrectly positioned sclerostomies. Choroidal detachment and significant shallowing of the anterior chamber did not occur. Excimer laser sclerostomy appears to be a viable technique for filtration, provided that mask placement is accurate.

Keywords

Glaucoma Rhesus Monkey Pulse Repetition Rate Choroidal Detachment Filtration Procedure 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Allan BDS, van Saarloos PP, Cooper RL, Constable IJ (1992) Laser microsclerostomy for primary open angle glaucoma: a review of laser mechanisms and delivery systems. Eye 6:257–266Google Scholar
  2. 2.
    Allan BDS, van Saarloos PP, Russo AV, Cooper RL, Constable IJ (1993) Excimer laser sclerostomy: the in vitro development of a modified open mask delivery system. Eye 7:47–52Google Scholar
  3. 3.
    Berlin M, Martinez M, Peter-Loercher H (1991) Erbium YAG laser sclerostomy: mechanism and histological analysis. Invest Ophthalmol Vis Sci 32 [ARVO Suppl]:196Google Scholar
  4. 4.
    Blok MDW, Kok JHC, Cor van Mil OD et al. (1990) Use of the megasoft bandage lens for the treatment of complications after trabeculectomy. Am J Ophthalmol 110:264–268Google Scholar
  5. 5.
    Desjardins DC, Parish RK, Foldberg R et al. (1986) Wound healing after filtering surgery in owl monkeys. Arch Ophthalmol 104:1835–1839Google Scholar
  6. 6.
    Fleck BW (1990) How large must an iridotomy be. Br J Ophthalmol 74:583–588Google Scholar
  7. 7.
    Hoskins HD, Iwach AG, Drake MV (1990) Subconjunctival THC:YAG laser limbal sclerostomy ab externo in the rabbit. Ophthalmic Surg 21:589–592Google Scholar
  8. 8.
    Hoskins HD, Iwach AG, Vassiliadis A et al. (1991) Subconjunctival THC:YAG laser thermal sclerostomy. Ophthalmology 98:1394–1400Google Scholar
  9. 9.
    Jampel HD, McGuigan LJB, Dunkelburger GR et al. (1988) Cellular proliferation after experimental glaucoma filtration surgery. Arch Ophthalmol 106:89–94Google Scholar
  10. 10.
    Jampel HD, Leong KW, Dunkelburger GR, Quigley HA (1990) Glaucoma filtration surgery in monkeys using 5-fluorouridine in polyanhydride disks. Arch Ophthalmol 108:430–435Google Scholar
  11. 11.
    Kaufmann PL, Davis GE (1980) Minified Goldmann applanating prism for tonometry in monkeys and humans. Arch Ophthalmol 898:542–546Google Scholar
  12. 12.
    Marshall J, Trokel S, Rothery S, Kruger RR (1986) A comparative study of corneal incisions induced by diamond and steel knives and two ultraviolet radiations from an excimer laser. Br J Ophthalmol 70:482–501Google Scholar
  13. 13.
    Quigley HA, Hohman R (1983) Laser energy levels for trabecular meshwork damage in the primate eye. Invest Opthhalmol Vis Sci 24:1305–1307Google Scholar
  14. 14.
    Seiler T, Kriegerowski M, Patmore A, Marshall J (1990) Partial external trabeculectomy with the excimer laser: an experimental investigation of a new treatment for glaucoma. Lasers Light Ophthalmol 3:97–109Google Scholar
  15. 15.
    Skuta GL, Parrish RK (1987) Wound healing in glaucoma filtering surgery. Surv Ophthalmol 32:149–170Google Scholar

Copyright information

© Springer-Verlag 1993

Authors and Affiliations

  • B. D. S. Allan
    • 1
  • P. P. van Saarloos
    • 1
  • R. L. Cooper
    • 1
  • E. J. Keogh
    • 1
  • L. J. Constable
    • 1
  1. 1.The Lions Eye InstituteNedlandsWestern Australia

Personalised recommendations