Abstract
A modified open mask system incorporating an en face air jet to dry the target area during ablation and a conjunctival plication mechanism, which allows ab externo delivery of the 193 nm excimer laser without prior conjunctival dissection, has been developed to form small bore sclerostomies accurately and atraumatically. Full thickness sclerostomies, and sclerostomies guarded by a smaller internal ostium can be created. A pilot therapeutic trial was conducted in pseudophakic patients with advanced open angle glaucoma. Six full thickness sclerostomies (200 microns and 400 microns diameter) and three guarded sclerostomies were created in nine patients by 193 nm excimer laser ablation (fluence per pulse 400 mJ/cm2, pulse rate 16 Hz, air jet pressure intraocular pressure +25 mm Hg). After 6 months' follow up, intraocular pressure was controlled (< or = 16 mm Hg) in eight of the nine patients (6/9 without medication). Early postoperative complications included hyphaema (trace--2.5 mm) (6/9), temporary fibrinous sclerostomy occlusion (4/9), profound early hypotony (all patients without fibrinous occlusion), and suprachoroidal haemorrhage in one case. Conjunctival laser wounds were self sealing. Small bore laser sclerostomy procedures are functionally equivalent to conventional full thickness procedures, producing early postoperative hypotony, with an increased risk of suprachoroidal haemorrhage in association with this. Further research is required to improve control over internal guarding in excimer laser sclerostomy before clinical trials of this technique can safely proceed.
Full text
PDFImages in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Addicks E. M., Quigley H. A., Green W. R., Robin A. L. Histologic characteristics of filtering blebs in glaucomatous eyes. Arch Ophthalmol. 1983 May;101(5):795–798. doi: 10.1001/archopht.1983.01040010795021. [DOI] [PubMed] [Google Scholar]
- Allan B. D., Barrett G. D. Combined small incision phacoemulsification and trabeculectomy. J Cataract Refract Surg. 1993 Jan;19(1):97–102. doi: 10.1016/s0886-3350(13)80292-1. [DOI] [PubMed] [Google Scholar]
- Allan B. D., Van Saarloos P. P., Cooper R. L., Constable I. J. Laser microsclerostomy for primary open angle glaucoma: a review of laser mechanisms and delivery systems. Eye (Lond) 1992;6(Pt 3):257–266. doi: 10.1038/eye.1992.49. [DOI] [PubMed] [Google Scholar]
- Allan B. D., van Saarloos P. P., Cooper R. L., Keogh E. J., Constable I. J. 193-nm excimer laser sclerostomy using a modified open mask delivery system in rhesus monkeys with experimental glaucoma. Graefes Arch Clin Exp Ophthalmol. 1993 Nov;231(11):662–666. doi: 10.1007/BF00921962. [DOI] [PubMed] [Google Scholar]
- Allan B. D., van Saarloos P. P., Russo A. V., Cooper R. L., Constable I. J. Excimer laser sclerostomy: the in vitro development of a modified open mask delivery system. Eye (Lond) 1993;7(Pt 1):47–52. doi: 10.1038/eye.1993.11. [DOI] [PubMed] [Google Scholar]
- Au Y. K., Reynolds M. D., Chadalavada R., Misra R. P. Bipolar cautery and internal thermal sclerostomy in a rabbit model. Ophthalmic Surg. 1992 Mar;23(3):188–191. [PubMed] [Google Scholar]
- Blok M. D., Kok J. H., van Mil C., Greve E. L., Kijlstra A. Use of the Megasoft Bandage Lens for treatment of complications after trabeculectomy. Am J Ophthalmol. 1990 Sep 15;110(3):264–268. doi: 10.1016/s0002-9394(14)76342-1. [DOI] [PubMed] [Google Scholar]
- Cooper H. M., Schuman J. S., Puliafito C. A., McCarthy D., Woods W. J., Friedman N., Wang N., Lin C. P. Picosecond neodymium:yttrium lithium fluoride laser sclerectomy. Am J Ophthalmol. 1993 Feb 15;115(2):221–224. doi: 10.1016/s0002-9394(14)73927-3. [DOI] [PubMed] [Google Scholar]
- Fleck B. W. How large must an iridotomy be? Br J Ophthalmol. 1990 Oct;74(10):583–588. doi: 10.1136/bjo.74.10.583. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gressel M. G., Parrish R. K., 2nd, Heuer D. K. Delayed nonexpulsive suprachoroidal hemorrhage. Arch Ophthalmol. 1984 Dec;102(12):1757–1760. doi: 10.1001/archopht.1984.01040031421015. [DOI] [PubMed] [Google Scholar]
- Higginbotham E. J., Kao G., Peyman G. Internal sclerostomy with the Nd: YAG contact laser versus thermal sclerostomy in rabbits. Ophthalmology. 1988 Mar;95(3):385–390. doi: 10.1016/s0161-6420(88)33175-1. [DOI] [PubMed] [Google Scholar]
- Hill R. A., Ozler S. A., Baerveldt G., Viscardi J. J., Keates R. H., Lee M., Harrington J. A., Berns M. W. Ab-interno neodymium:YAG versus erbium:YAG laser sclerostomies in a rabbit model. Ophthalmic Surg. 1992 Mar;23(3):192–197. [PubMed] [Google Scholar]
- Iwach A. G., Hoskins H. D., Jr, Drake M. V., Dickens C. J. Subconjunctival THC:YAG ("holmium") laser thermal sclerostomy ab externo. A one-year report. Ophthalmology. 1993 Mar;100(3):356–366. [PubMed] [Google Scholar]
- Joseph J. P., Grierson I., Hitchings R. A. Chemotactic activity of aqueous humor. A cause of failure of trabeculectomies? Arch Ophthalmol. 1989 Jan;107(1):69–74. doi: 10.1001/archopht.1989.01070010071030. [DOI] [PubMed] [Google Scholar]
- Konstas A. G., Jay J. L. Modification of trabeculectomy to avoid postoperative hyphaema. The 'guarded anterior fistula' operation. Br J Ophthalmol. 1992 Jun;76(6):353–357. doi: 10.1136/bjo.76.6.353. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Krug J. H., Jr, Melamed S. Adjunctive use of delayed and adjustable low-dose 5-fluorouracil in refractory glaucoma. Am J Ophthalmol. 1990 Apr 15;109(4):412–418. doi: 10.1016/s0002-9394(14)74607-0. [DOI] [PubMed] [Google Scholar]
- Lewis A., Palanker D., Hemo I., Pe'er J., Zauberman H. Microsurgery of the retina with a needle-guided 193-nm excimer laser. Invest Ophthalmol Vis Sci. 1992 Jul;33(8):2377–2381. [PubMed] [Google Scholar]
- Mao L. K., Stewart W. C., Shields M. B. Correlation between intraocular pressure control and progressive glaucomatous damage in primary open-angle glaucoma. Am J Ophthalmol. 1991 Jan 15;111(1):51–55. doi: 10.1016/s0002-9394(14)76896-5. [DOI] [PubMed] [Google Scholar]
- Marshall J. Lasers in ophthalmology: the basic principles. Eye (Lond) 1988;2 (Suppl):S98–112. doi: 10.1038/eye.1988.137. [DOI] [PubMed] [Google Scholar]
- Marshall J., Trokel S., Rothery S., Krueger R. R. A comparative study of corneal incisions induced by diamond and steel knives and two ultraviolet radiations from an excimer laser. Br J Ophthalmol. 1986 Jul;70(7):482–501. doi: 10.1136/bjo.70.7.482. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Marshall J., Trokel S., Rothery S., Schubert H. An ultrastructural study of corneal incisions induced by an excimer laser at 193 nm. Ophthalmology. 1985 Jun;92(6):749–758. doi: 10.1016/s0161-6420(85)33961-1. [DOI] [PubMed] [Google Scholar]
- Ortiz J. R., Walker S. D., McManus P. E., Martinez L. A., Brown R. H., Jaffe G. J. Filtering bleb thrombolysis with tissue plasminogen activator. Am J Ophthalmol. 1988 Nov 15;106(5):624–625. doi: 10.1016/0002-9394(88)90598-3. [DOI] [PubMed] [Google Scholar]
- Ozler S. A., Hill R. A., Andrews J. J., Baerveldt G., Berns M. W. Infrared laser sclerostomies. Invest Ophthalmol Vis Sci. 1991 Aug;32(9):2498–2503. [PubMed] [Google Scholar]
- Preziosi C. L. THE ELECTRO-CAUTERY IN THE TREATMENT OF GLAUCOMA. Br J Ophthalmol. 1924 Sep;8(9):414–417. doi: 10.1136/bjo.8.9.414. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schuman J. S., Stinson W. G., Hutchinson B. T., Bellows A. R., Puliafito C. A., Lytle R. Holmium laser sclerectomy. Success and complications. Ophthalmology. 1993 Jul;100(7):1060–1065. doi: 10.1016/s0161-6420(93)31538-1. [DOI] [PubMed] [Google Scholar]
- Seiler T., Kriegerowski M., Bende T., Wollensak J. Partielle externe Trabekulektomie. Klin Monbl Augenheilkd. 1989 Oct;195(4):216–220. doi: 10.1055/s-2008-1046442. [DOI] [PubMed] [Google Scholar]
- Shahinian L., Jr, Egbert P. R., Williams A. S. Histologic study of healing after ab interno laser sclerostomy. Am J Ophthalmol. 1992 Aug 15;114(2):216–219. doi: 10.1016/s0002-9394(14)73988-1. [DOI] [PubMed] [Google Scholar]
- Skuta G. L., Parrish R. K., 2nd Wound healing in glaucoma filtering surgery. Surv Ophthalmol. 1987 Nov-Dec;32(3):149–170. doi: 10.1016/0039-6257(87)90091-9. [DOI] [PubMed] [Google Scholar]
- Traverso C. E., Murialdo U., Di Lorenzo G., Venzano D., De Palma G., Gandolfo E., Calabria G. A., Zingirian M. Photoablative filtration surgery with the excimer laser for primary open-angle glaucoma: a pilot study. Int Ophthalmol. 1992 Sep;16(4-5):363–365. doi: 10.1007/BF00917992. [DOI] [PubMed] [Google Scholar]
- Tripathi R. C., Tripathi B. J., Park J. K., Quaranta L., Steinspair K., Lehman E., Ernest J. T. Intracameral tissue plasminogen activator for resolution of fibrin clots after glaucoma filtering procedures. Am J Ophthalmol. 1991 Feb 15;111(2):247–248. doi: 10.1016/s0002-9394(14)72272-x. [DOI] [PubMed] [Google Scholar]
- Van Saarloos P. P., Constable I. J. Bovine corneal stroma ablation rate with 193-nm excimer laser radiation: quantitative measurement. Refract Corneal Surg. 1990 Nov-Dec;6(6):424–429. [PubMed] [Google Scholar]