Incisional Therapies: Canaloplasty and New Implant Devices

  • Diamond Y. Tam
  • Iqbal “Ike” K. Ahmed


Incisional surgery for the treatment of glaucoma was first described in 1896 with surgical iridectomy, followed by corneo-scleral trephination in the 1920s and full thickness procedures in the 1950s. In 1968, Cairns described the technique of trabeculectomy, still considered by many today to be the gold standard of glaucoma surgery. Techniques have been modified and the addition of adjunctive antimetabolites has perhaps improved the original procedure to enhance long-term success and survival, as measured by intraocular pressure reduction and control, but the common final goal remains to create and maintain a nonphysiologic fistula from the anterior chamber to the subconjunctival space. Although lowering of intraocular pressure (IOP) is undisputable and well established, the generous complication profile of these procedures is well known. Both short-term and long-term risks of blebitis, endophthalmitis, hypotony, overfiltration, bleb leaks, dysesthesia, overhang, encapsulation, corneal dellen, endo­thelial cell loss, episcleral fibrosis, aqueous misdirection, and accelerated cataract formation are some of the many potential complications, most of which are lifetime risks for patients undergoing trabeculectomy.


Anterior Chamber Aqueous Humor Trabecular Meshwork Scleral Flap Aqueous Outflow 
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.


  1. 1.
    Richey SO. Management of glaucoma. Trans Am Ophthalmol Soc. 1896;7:723–730.PubMedGoogle Scholar
  2. 2.
    Davenport RC. The after results of corneo-scleral trephining for glaucoma. Br J Ophthalmol. 1926;10(9):478–484.CrossRefPubMedGoogle Scholar
  3. 3.
    Scheie HG. Retraction of scleral wound edges; as a fistulizing procedure for glaucoma. Am J Ophthalmol. 1958;45(4, Part 2):220–229.PubMedGoogle Scholar
  4. 4.
    Cairns JE. Trabeculectomy. Preliminary report of a new method. Am J Ophthalmol. 1968;66(4):673–679.PubMedGoogle Scholar
  5. 5.
    Borisuth NS, Phillips B, Krupin T. The risk profile of glaucoma filtration surgery. Curr Opin Ophthalmol. 1999;10(2):112–116.CrossRefPubMedGoogle Scholar
  6. 6.
    Rollett M, Moreau M. Le drainage au crin de la chambre anterieure contre l’hypertonie et la douleur. Rev Gen Ophtalmol. 1907;26:289–292.Google Scholar
  7. 7.
    Molteno ACB. New implant for drainage in glaucoma: animal trial. Br J Ophthalmol. 1969;53:161–168.CrossRefPubMedGoogle Scholar
  8. 8.
    Molteno ACB. New implant for drainage in glaucoma: clinical trial. Br J Ophthalmol. 1969;53:606–615.CrossRefPubMedGoogle Scholar
  9. 9.
    Krupin T, Podos SM, Becker B, Newkirk JB. Valve implants in filtering surgery. Am J Ophthalmol. 1976;81(2):232–235.PubMedGoogle Scholar
  10. 10.
    Lloyd MA, Baerveldt G, Heuer DK, Minckler DS, Martone JF. Initial clinical experience with the Baerveldt implant in complicated glaucomas. Ophthalmology. 1994;101(4):640–650.PubMedGoogle Scholar
  11. 11.
    Coleman AL, Hill R, Wilson MR, et al. Initial clinical experience with the Ahmed Glaucoma Valve implant. Am J Ophthalmol. 1995;120(1):23–31.PubMedGoogle Scholar
  12. 12.
    Barkan O. Goniotomy for the relief of congenital glaucoma. Br J Ophthalmol. 1948;32(9):701–728.CrossRefGoogle Scholar
  13. 13.
    Scheie HG. Goniotomy in the treatment of congenital glaucoma. Trans Am Ophthalmol Soc. 1949;47:115–137.PubMedGoogle Scholar
  14. 14.
    Bill A, Phillips CI. Uveoscleral drainage of aqueous humor in human eyes. Exp Eye Res. 1971;12:275–281.CrossRefPubMedGoogle Scholar
  15. 15.
    Toris CB, Yablonski ME, Wang YL, et al. Aqueous humor dynamics in the aging human eye. Am J Ophthalmol. 1999;127:407–412.CrossRefPubMedGoogle Scholar
  16. 16.
    Bindlish R, Condon GP, Schlosser JD, D’Antonio J, Lauer KB, Lehrer R. Efficacy and safety of mitomycin-C in primary trabeculectomy: five-year follow-up. Ophthalmology. 2002;109(7):1336–1341.CrossRefPubMedGoogle Scholar
  17. 17.
    Palmer SS. Mitomycin as adjunct chemotherapy with trabeculectomy. Ophthalmology. 1991;98(3):317–321.PubMedGoogle Scholar
  18. 18.
    Fluorouracil Filtering Surgery Study one-year follow-up. The Fluorouracil Filtering Surgery Study Group. Am J Ophthalmol. 1989;108(6):625–635.Google Scholar
  19. 19.
    Kupin TH, Juzych MS, Shin DH, Khatana AK, Olivier MM. Adjunctive mitomycin C in primary trabeculectomy in phakic eyes. Am J Ophthalmol. 1995;119(1):30–39.PubMedGoogle Scholar
  20. 20.
    Ticho U, Ophir A. Late complications after glaucoma filtering surgery with adjunctive 5-fluorouracil. Am J Ophthalmol. 1993;115(4):506–510.PubMedGoogle Scholar
  21. 21.
    Gedde SJ, Schiffman JC, Feuer WJ, Herndon LW, Brandt JD, Budenz DL. Treatment outcomes in the tube versus trabeculectomy study after one year of follow-up. Am J Ophthalmol. 2007;143(1):9–22.CrossRefPubMedGoogle Scholar
  22. 22.
    Gedde SJ, Herndon LW, Brandt JD, Budenz DL, Feuer WJ, Schiffman JC. Surgical complications in the Tube Versus Trabeculectomy Study during the first year of follow-up. Am J Ophthalmol. 2007;143(1):23–31.CrossRefPubMedGoogle Scholar
  23. 23.
    Grant WM. Further studies on facility of flow through the trabecular meshwork. AMA Arch Ophthalmol. 1958;60(4 part 1):523–533.PubMedGoogle Scholar
  24. 24.
    Rosenquist R, Epstein D, Melamed S, Johnson M, Grant WM. Outflow resistance of enucleated human eyes at two different perfusion pressures and different extents of trabeculotomy. Curr Eye Res. 1989;8(12):1233–1240.CrossRefPubMedGoogle Scholar
  25. 25.
    Ethier CR, Kamm RD, Palaszewski BA, Johnson MC, Richardson TM. Calculations of flow resistance in the juxtacanalicular meshwork. Invest Ophthalmol Vis Sci. 1986;27(12):1741–1750.PubMedGoogle Scholar
  26. 26.
    Epstein E. Fibrosing response to aqueous; its relation to glaucoma. Br J Ophthalmol. 1959;43:641–647.CrossRefPubMedGoogle Scholar
  27. 27.
    Krasnov MM. Externalization of Schlemm’s canal (sinusotomy) in glaucoma. Br J Ophthalmol. 1968;52:157–161.CrossRefPubMedGoogle Scholar
  28. 28.
    Ellingsen BA, Grant WM. Trabeculotomy and sinusotomy in enucleated human eyes. Invest Ophthalmol. 1972;11:21–28.PubMedGoogle Scholar
  29. 29.
    Johnstone MA, Grant WM. Microsurgery of Schlemm’s canal and the human aqueous outflow system. Am J Ophthalmol. 1973;76: 906–917.PubMedGoogle Scholar
  30. 30.
    Koslov VI, Bagrov SN, Anisimova SY, et al. [Nonpenetrating deep sclerectomy with collagen] [Russian]. Oftalmokhirurgiia. 1990;3: 44–46.Google Scholar
  31. 31.
    Fyodorov SN, Ioffe DI, Ronkina TI. Deep sclerectomy: technique and mechanism of a new antiglaucomatous procedure. Glaucoma. 1984;6:281–283.Google Scholar
  32. 32.
    Zimmerman TJ, Kooner KS, Ford VJ, et al. Trabeculectomy vs. nonpenetrating trabeculectomy: a retrospective study of two procedures in phakic patients with glaucoma. Ophthalmic Surg. 1984;15: 734–740.PubMedGoogle Scholar
  33. 33.
    Stegmann R, Pienaar A, Miller D. Viscocanalostomy for open angle glaucoma in black African patients. J Cataract Refract Surg. 1999;25:316–322.CrossRefPubMedGoogle Scholar
  34. 34.
    Sourdille P, Santiago P-Y, Villain F, et al. Reticulated hyaluronic acid implant in nonperforating trabecular surgery. J Cataract Refract Surg. 1999;25:332–339.CrossRefPubMedGoogle Scholar
  35. 35.
    Ambresin A, Shaarawy T, Mermoud A. Deep sclerectomy with collagen implant in one eye compared with trabeculectomy in the other eye of the same patient. J Glaucoma. 2002;11:214–220.CrossRefPubMedGoogle Scholar
  36. 36.
    Sanchez E, Schnyder CC, Sickenberg M, Chiou AG, Hédiguer SE, Mermoud A. Deep sclerectomy: results with and without collagen implant. Int Ophthalmol. 1996/97;20:157–162.Google Scholar
  37. 37.
    Spiegel D, Kobuch K. Trabecular meshwork bypass tube shunt: initial case series. Br J Ophthalmol. 2002;86:1228–1231.CrossRefPubMedGoogle Scholar
  38. 38.
    Yablonski ME. Trabeculectomy with internal tube shunt: a novel glaucoma surgery. J Glaucoma. 2005;14:91–97.CrossRefPubMedGoogle Scholar
  39. 39.
    Lewis RA, von Wolff K, Tetz M, et al. Canaloplasty: circumferential viscodilation and tensioning of Schlemm’s canal using a flexible microcatheter for the treatment of open-angle glaucoma in adults: interim clinical study analysis. J Cataract Refract Surg. 2007;33(7): 1217–1226.CrossRefPubMedGoogle Scholar
  40. 40.
    Luntz MH, Livingston DG. Trabeculotomy ab externo and trabeculectomy in congenital and adult-onset glaucoma. Am J Ophthalmol. 1977;83:174–179.PubMedGoogle Scholar
  41. 41.
    Tanihara H, Negi A, Akimoto M, et al. Surgical effects of trabeculectomy ab externo on adult eyes with primary open angle glaucoma and pseudoexfoliation syndrome. Arch Ophthalmol. 1993;111:1653–1661.PubMedGoogle Scholar
  42. 42.
    Krasnov MM. Q-switched laser goniopuncture. Arch Ophthalmol. 1974;92:37–41.PubMedGoogle Scholar
  43. 43.
    Wickham MG, Worthen DM. Argon laser trabeculotomy: long-term follow-up. Ophthalmology. 1970;86:495–503.Google Scholar
  44. 44.
    Epstein DL, Melamed S, Puliatio CA, Steinert RF. Neodymium: YAG laser trabeculopuncture in open-angle glaucoma. Ophthalmology. 1985;92:931–937.PubMedGoogle Scholar
  45. 45.
    Bahler CK, Smedley GT, Zhou J, Johnson DH. Trabecular bypass stents decrease intraocular pressure in cultured human anterior segments. Am J Ophthalmol. 2004;138(6):988–994.CrossRefPubMedGoogle Scholar
  46. 46.
    Spiegel D, Wetzel W, Haffner DS, Hill RA. Initial clinical experience with the trabecular micro-bypass stent in patients with glaucoma. Adv Ther. 2007;24(1):161–170.CrossRefPubMedGoogle Scholar
  47. 47.
    Minckler D, Baerveldt G, Ramirez MA, et al. Clinical results with the Trabectome, a novel surgical device for treatment of open-angle glaucoma. Trans Am Ophthalmol Soc. 2006;104:40–50.PubMedGoogle Scholar
  48. 48.
    Francis BA, See RF, Rao NA, Minckler DS, Baerveldt G. Ab interno trabeculectomy: development of a novel device (TrabectomeTM) and surgery for open-angle glaucoma. J Glaucoma. 2006;15:68–73.CrossRefPubMedGoogle Scholar
  49. 49.
    Minckler DS, Baerveldt G, Alfaro MR, Francis BA. Clinical results with the Trabectome for treatment of open-angle glaucoma. Ophthalmology. 2005;112:962–967.CrossRefPubMedGoogle Scholar
  50. 50.
    Bain WE. Variations in the episcleral venous pressure in relation to glaucoma. Br J Ophthalmol. 1954;38(3):129–135.CrossRefPubMedGoogle Scholar
  51. 51.
    Friberg TR, Sanborn G, Weinreb RN. Intraocular and episcleral venous pressure increase during inverted posture. Am J Ophthalmol. 1987;103(4):523–526.PubMedGoogle Scholar
  52. 52.
    Phelps CD. The pathogenesis of glaucoma in Sturge-Weber syndrome. Ophthalmology. 1978;85(3):276–286.PubMedGoogle Scholar
  53. 53.
    Bigger JF. Glaucoma with elevated episcleral venous pressure. South Med J. 1975;68(11):1444–1448.PubMedGoogle Scholar
  54. 54.
    Suguro K, Toris CB, Pederson JE. Uveoscleral outflow following cyclodialysis in the monkey eye using a fluorescent tracer. Invest Ophthalmol Vis Sci. 1985;26:810–813.PubMedGoogle Scholar
  55. 55.
    Jordan JF, Dietlein TS, Dinslage S, et al. Cyclodialysis ab interno as a surgical approach to intractable glaucoma. Graefes Arch Clin Exp Ophthalmol. 2007;245:1071–1076.CrossRefPubMedGoogle Scholar
  56. 56.
    Shields MB, Simmons RJ. Combined cyclodialysis and cataract extraction. Ophthalmic Surg. 1976;7(2):62–73.PubMedGoogle Scholar
  57. 57.
    Galin MA, Baras I. Combined cyclodialysis cataract extraction: a review. Ann Ophthalmol. 1975;7(2):271–275.PubMedGoogle Scholar
  58. 58.
    Gills JP Jr, Paterson CA, Paterson ME. Action of cyclodialysis utilizing an implant studied by manometry in a human eye. Exp Eye Res. 1967;6:75–78.CrossRefPubMedGoogle Scholar
  59. 59.
    Klemm M, Balazs A, Draeger J, Wiezorrek R. Experimental use of space-retaining substances with extended duration: functional and morphological results. Graefes Arch Clin Exp Ophthalmol. 1995;233(9):592–597.CrossRefPubMedGoogle Scholar
  60. 60.
    Nesterov AP, Batmanov YE, Cherkasova IN, Egorov EA. Surgical stimulation of the uveoscleral outflow: experimental studies on enucleated human eyes. Acta Ophthalmol (Copenh). 1979;57(3):409–417.CrossRefGoogle Scholar
  61. 61.
    Pinnas G, Boniuk M. Cyclodialysis with teflon tube implants. Am J Ophthalmol. 1969;68(5):879–883.PubMedGoogle Scholar
  62. 62.
    Krejci L. Cyclodialysis with hydroxyethyl methacrylate capillary strip. Ophthalmologica. 1972;164:113–121.CrossRefPubMedGoogle Scholar
  63. 63.
    Ozdamar A, Aras C, Karacorlu M. Suprachoroidal seton implantation in refractory glaucoma: a novel surgical technique. J Glaucoma. 2003;12:354–359.CrossRefPubMedGoogle Scholar
  64. 64.
    Jordan JF, Engels BF, Dinslage S, et al. A novel approach to suprachoroidal drainage for the surgical treatment of intractable glaucoma. J Glaucoma. 2006;15:200–205.CrossRefPubMedGoogle Scholar
  65. 65.
    Sarkisian SR. Use of an Injector for the Ex-PRESS™ Mini Glaucoma Shunt. Ophthalmic Surg Lasers Imaging. 2007;38(5):434–436.PubMedGoogle Scholar
  66. 66.
    Coupin A, Li Q, Riss I. Ex-PRESS miniature glaucoma implant inserted under a scleral flap in open-angle glaucoma surgery: a retrospective study. Fr J Glaucoma. 2007;30(1):18–23.Google Scholar
  67. 67.
    Maris PJG, Ishida K, Netland PA. Comparison of trabeculectomy with Ex-PRESS miniature glaucoma device implanted under scleral flap. J Glaucoma. 2007;16:14–19.CrossRefPubMedGoogle Scholar
  68. 68.
    Dahan E, Carmichael TR. Implantation of a miniature glaucoma device under a scleral flap. J Glaucoma. 2005;14(2):98–102.CrossRefPubMedGoogle Scholar
  69. 69.
    Traverso CE, De Feo F, Messas-Kaplan A, et al. Long term effect on IOP of a stainless steel glaucoma drainage implant (Ex-PRESS) in combined surgery with phacoemulsification. Br J Ophthalmol. 2005;89(4):425–429.CrossRefPubMedGoogle Scholar
  70. 70.
    Nyska A, Glovinsky Y, Belkin M, Epstein Y. Biocompatibility of the Ex-PRESS miniature glaucoma drainage implant. J Glaucoma. 2003;12(3):275–280.CrossRefPubMedGoogle Scholar
  71. 71.
    Moses RA, Grodzki WJ Jr, Etheridge EL, Wilson CD. Schlemm’s canal: the effect of intraocular pressure. Invest Ophthalmol Vis Sci. 1981;20(1):61–68.PubMedGoogle Scholar
  72. 72.
    Shingleton B, Tetz M, Korber N. Circumferential viscodilation and tensioning of Schlemm’s canal (canaloplasty) combined with temporal clear corneal phacoemulsification cataract surgery for the treatment of open angle glaucoma and visually significant cataract - one year results. J Cataract Refract Surg. 2008;34(3):433–440.CrossRefPubMedGoogle Scholar
  73. 73.
    Grant WM. Experimental aqueous perfusion in enucleated human eyes. Arch Ophthalmol. 1963;69:783–801.PubMedGoogle Scholar
  74. 74.
    Zhou J, Smedley GT. A trabecular bypass flow hypothesis. J Glaucoma. 2005;14(1):74–83.CrossRefPubMedGoogle Scholar
  75. 75.
    Zhou J, Smedley GT. Trabecular bypass: effect of Schlemm canal and collector channel dilation. J Glaucoma. 2006;15(5):446–455.CrossRefPubMedGoogle Scholar
  76. 76.
    Herschler J, Davis EB. Modified goniotomy for inflammatory glaucoma. Histologic evidence for the mechanism of pressure reduction. Arch Ophthalmol. 1980;98:684–687.PubMedGoogle Scholar
  77. 77.
    Gramer E, Tausch M, Kraemer C. Time of diagnosis, reoperations and long-term results of goniotomy in the treatment of primary congenital glaucoma: a clinical study. Int Ophthalmol. 1996;20: 117–123.PubMedGoogle Scholar
  78. 78.
    Mendicino ME, Lynch MG, Drack A, et al. Long-term surgical and visual outcomes in primary congenital glaucoma: 360 degrees trabeculotomy versus goniotomy. J AAPOS. 2000;4:205–210.CrossRefPubMedGoogle Scholar
  79. 79.
    Dickens CS, Hoskins HD Jr. Epidemiology and pathophysiology of congenital glaucoma. In: Ritch R, Shields MB, Krupin T, eds. The Glaucomas, vol. 2. 2nd ed. St. Louis: Mosby; 1996:729–738.Google Scholar
  80. 80.
    Hill RA, Baerveldt G, Ozler SA, et al. Laser trabecular ablation (LTA). Lasers Surg Med. 1991;11:341–346.CrossRefPubMedGoogle Scholar
  81. 81.
    Jacobi PC, Dietlein TS, Krieglstein GK. Technique of goniocurettage: a potential treatment for advanced chronic open angle glaucoma. Br J Ophthalmol. 1997;81:302–307.CrossRefPubMedGoogle Scholar
  82. 82.
    Eisler R. Mammalian sensitivity to elemental gold (Au). Biol Trace Elem Res. 2004;100:1–17.CrossRefPubMedGoogle Scholar
  83. 83.
    Sen SC, Ghosh A. Gold as an intraocular foreign body. Br J Ophthalmol. 1983;67:398–399.CrossRefPubMedGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Diamond Y. Tam
    • 1
  • Iqbal “Ike” K. Ahmed
    • 2
  1. 1.Department of Ophthalmology and Vision Sciences, Credit Valley Eye CareUniversity of TorontoMississaugaCanada
  2. 2.Department of OphthalmologyCredit Valley Eye CareMississaugaCanada

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