Abstract
AIM—To introduce a new concept of anterior chamber angle microsurgery, designed to scrape pathologically altered trabecular meshwork from the scleral sulcus as a potential treatment in primary open angle glaucoma. METHODS—Gonioscopically controlled ab interno abrasion of the trabecular meshwork was performed on six human eye banking eyes for morphological analysis. Thereafter, four eyes suffering from terminal glaucomatous optic nerve atrophy as a result of medically uncontrolled intraocular pressure were also treated by `goniocurettage'. The newly designed instrument resembles a modified cyclodialysis spatula with a bowl-shaped tip, 300 µm in diameter, and with its edges sharpened. The treatment zone comprised 4-5 clock hours of the chamber angle circumference. RESULTS—Microscopic examination of the treatment zone revealed that in addition to a complete disruption of the trabecular meshwork and internal wall of Schlemm's canal goniocurettage also caused damage to intracanalicular septa. A splitting along the posterior wall of Schlemm's canal was also noted in one specimen. The clinical data of goniocurettage also showed some promising results. Mean pretreatment IOP averaged 40.7 (SD 8.8) mm Hg (range 32-51 mm Hg) and was significantly (p<0.04) reduced to 18.0 (4.2) mm Hg (12-22 mm Hg) after 6 months, representing an absolute decrease in IOP of 22.7 mm Hg and a mean decrease in IOP of 56%. Clinically significant hyphaema occurred in one eye, caused by iatrogenic trauma to a prominent chamber angle vessel. In three eyes a minor reflux of blood occurred at the treatment site. However, no hypotony, choroidal effusion, flattened anterior chamber, or cyclodialysis were observed in these patients. CONCLUSION—Morphological analysis of treated postmortem eyes confirmed that goniocurettage completely removed the trabecular meshwork and opened Schlemm's canal, ensuring direct access into the anterior chamber. In a small number of patients over a limited period of time this new surgical procedure resulted in a clinically significant pressure reduction. However, longer term follow up and a greater number of patients are warranted before this experimental procedure is applicable to eyes that would do well with conventional surgery.
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- ALLEN L., BURIAN H. M. Trabeculotomy ab externo. A new glaucoma operation: technique and results of experimental surgery. Am J Ophthalmol. 1962 Jan;53:19–26. [PubMed] [Google Scholar]
- Anderson D. R. Trabeculotomy compared to goniotomy for glaucoma in children. Ophthalmology. 1983 Jul;90(7):805–806. doi: 10.1016/s0161-6420(83)34484-5. [DOI] [PubMed] [Google Scholar]
- Berlin M. S., Yoo P. H., Ahn R. J. The role of laser sclerostomy in glaucoma surgery. Curr Opin Ophthalmol. 1995 Apr;6(2):102–114. doi: 10.1097/00055735-199504000-00016. [DOI] [PubMed] [Google Scholar]
- Epstein D. L., Melamed S., Puliafto C. A., Steinert R. F. Neodymium: YAG laser trabeculopuncture in open-angle glaucoma. Ophthalmology. 1985 Jul;92(7):931–937. doi: 10.1016/s0161-6420(85)33932-5. [DOI] [PubMed] [Google Scholar]
- GRANT W. M. Experimental aqueous perfusion in enucleated human eyes. Arch Ophthalmol. 1963 Jun;69:783–801. doi: 10.1001/archopht.1963.00960040789022. [DOI] [PubMed] [Google Scholar]
- GRANT W. M. Further studies on facility of flow through the trabecular meshwork. AMA Arch Ophthalmol. 1958 Oct;60(4 Pt 1):523–533. doi: 10.1001/archopht.1958.00940080541001. [DOI] [PubMed] [Google Scholar]
- Grant W. M. Symposium: microsurgery of the outflow channels. Laboratory research. Trans Am Acad Ophthalmol Otolaryngol. 1972 Mar-Apr;76(2):398–404. [PubMed] [Google Scholar]
- Hill R. A., Baerveldt G., Ozler S. A., Pickford M., Profeta G. A., Berns M. W. Laser trabecular ablation (LTA). Lasers Surg Med. 1991;11(4):341–346. doi: 10.1002/lsm.1900110405. [DOI] [PubMed] [Google Scholar]
- Ito S., Nishikawa M., Tokura T., Yamane A., Yamagishi K., Miki H. [Histopathological study of trabecular meshwork after trabeculotomy in monkeys]. Nippon Ganka Gakkai Zasshi. 1994 Sep;98(9):811–819. [PubMed] [Google Scholar]
- Ito S., Nishikawa M., Tokura T., Yamane A., Yamagishi K., Miki H. [Histopathological study of trabecular meshwork after trabeculotomy in monkeys]. Nippon Ganka Gakkai Zasshi. 1994 Sep;98(9):811–819. [PubMed] [Google Scholar]
- Jay J. L., Murray S. B. Early trabeculectomy versus conventional management in primary open angle glaucoma. Br J Ophthalmol. 1988 Dec;72(12):881–889. doi: 10.1136/bjo.72.12.881. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kawase K., Nishimura K., Yamamoto T., Jikihara S., Kitazawa Y. Anterior chamber reaction after mitomycin and 5-fluorouracil trabeculectomy: a comparative study. Ophthalmic Surg. 1993 Jan;24(1):24–27. [PubMed] [Google Scholar]
- Latina M. A., Dobrogowski M., March W. F., Birngruber R. Laser sclerostomy by pulsed-dye laser and goniolens. Arch Ophthalmol. 1990 Dec;108(12):1745–1750. doi: 10.1001/archopht.1990.01070140099038. [DOI] [PubMed] [Google Scholar]
- Lee W. R., Dutton G. N., Cameron S. A. Short-pulsed neodymium-YAG laser trabeculotomy. An in vivo morphological study in the human eye. Invest Ophthalmol Vis Sci. 1988 Nov;29(11):1698–1707. [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]
- McPherson S. D., Jr, Berry D. P. Goniotomy vs external trabeculotomy for developmental glaucoma. Am J Ophthalmol. 1983 Apr;95(4):427–431. doi: 10.1016/0002-9394(83)90260-x. [DOI] [PubMed] [Google Scholar]
- Melamed S., Pei J., Puliafito C. A., Epstein D. L. Q-switched neodymium-YAG laser trabeculopuncture in monkeys. Arch Ophthalmol. 1985 Jan;103(1):129–133. doi: 10.1001/archopht.1985.01050010135037. [DOI] [PubMed] [Google Scholar]
- Nesterov A. P., Batmanov Y. E. Study on morphology and function of the drainage area of the eye of man. Acta Ophthalmol (Copenh) 1972;50(3):337–350. doi: 10.1111/j.1755-3768.1972.tb05956.x. [DOI] [PubMed] [Google Scholar]
- Nesterov A. P., Batmanov Y. E. Trabecular wall of Schlemm's canal in the early stage of primary open-angle glaucoma. Am J Ophthalmol. 1974 Oct;78(4):639–647. doi: 10.1016/s0002-9394(14)76302-0. [DOI] [PubMed] [Google Scholar]
- Nesterov A. P. Role of the blockade of Schlemm's canal in pathogenesis of primary open-angle glaucoma. Am J Ophthalmol. 1970 Nov;70(5):691–696. doi: 10.1016/0002-9394(70)90484-8. [DOI] [PubMed] [Google Scholar]
- Oram O., Gross R. L., Severin T. D., Orengo-Nania S., Feldman R. M. Gonioscopic ab interno Nd:YLF laser sclerostomy in human cadaver eyes. Ophthalmic Surg. 1995 Mar-Apr;26(2):136–138. [PubMed] [Google Scholar]
- Palmer S. S. Mitomycin as adjunct chemotherapy with trabeculectomy. Ophthalmology. 1991 Mar;98(3):317–321. doi: 10.1016/s0161-6420(91)32293-0. [DOI] [PubMed] [Google Scholar]
- Peyman G. A., Badaro R. M., Khoobehi B. Corneal ablation in rabbits using an infrared (2.9-microns) erbium: YAG laser. Ophthalmology. 1989 Aug;96(8):1160–1170. doi: 10.1016/s0161-6420(89)32755-2. [DOI] [PubMed] [Google Scholar]
- Schwartz A. L., Anderson D. R. Trabecular surgery. Arch Ophthalmol. 1974 Aug;92(2):134–138. doi: 10.1001/archopht.1974.01010010140012. [DOI] [PubMed] [Google Scholar]
- Segawa K. Electron microscopic changes of the trabecular tissue in primary open-angle glaucoma. Ann Ophthalmol. 1979 Jan;11(1):49–54. [PubMed] [Google Scholar]
- Shabo A. L., Reese T. S., Gaasterland D. Postmortem formation of giant endothelial vacuoles in Schlemm's canal of the monkey. Am J Ophthalmol. 1973 Dec;76(6):896–905. doi: 10.1016/0002-9394(73)90079-2. [DOI] [PubMed] [Google Scholar]
- Tanihara H., Negi A., Akimoto M., Terauchi H., Okudaira A., Kozaki J., Takeuchi A., Nagata M. Surgical effects of trabeculotomy ab externo on adult eyes with primary open angle glaucoma and pseudoexfoliation syndrome. Arch Ophthalmol. 1993 Dec;111(12):1653–1661. doi: 10.1001/archopht.1993.01090120075025. [DOI] [PubMed] [Google Scholar]
- Tawara A., Inomata H. Developmental immaturity of the trabecular meshwork in juvenile glaucoma. Am J Ophthalmol. 1984 Jul 15;98(1):82–97. doi: 10.1016/0002-9394(84)90193-4. [DOI] [PubMed] [Google Scholar]
- deLuise V. P., Anderson D. R. Primary infantile glaucoma (congenital glaucoma). Surv Ophthalmol. 1983 Jul-Aug;28(1):1–19. doi: 10.1016/0039-6257(83)90174-1. [DOI] [PubMed] [Google Scholar]
- van der Zypen E., Fankhauser F. The ultrastructural features of laser trabeculopuncture and cyclodialysis. Problems related to successful treatment of chronic simple glaucoma. Ophthalmologica. 1979;179(4):189–200. doi: 10.1159/000308894. [DOI] [PubMed] [Google Scholar]