eMedicine Specialties > Ophthalmology > Refractive Disorders

Myopia, Intracorneal Rings: Follow-up

Author: Manolette R Roque, MD, MBA, DPBO, FPAO, President and CEO, Chief of Service, Ocular Immunology and Uveitis, Consulting Staff, Cornea and Refractive Surgery, Eye Republic Ophthalmology Clinic; General Manager, Ophthalmic Consultants Philippines Co; Consulting Staff, CME Liaison, Section Chief of Ocular Immunology and Uveitis, Department of Ophthalmology, Asian Hospital and Medical Center
Coauthor(s): Barbara L Roque, MD, Full Partner, Ophthalmic Consultants Philippines Co, Chief of Service, Pediatric Ophthalmology and Strabismus, Consulting Staff, Orbit and Eye Plastics, Eye Republic Ophthalmology Clinic; Ruben Limbonsiong, MD, Chief of Service, Refractive Surgery Service and Vision Laser Center, St. Luke's Medical Center; Program Director, Clinical Assistant Professor, Department of Ophthalmology, University of the Philippines at Manila; Roberto Pineda, ll, MD, Scholar, The Academy at Harvard Medical School; Director, Refractive Surgery Service, Massachusetts Eye and Ear Infirmary
Contributor Information and Disclosures

Updated: Dec 19, 2008

Outcome and Prognosis

A summary of the safety and efficacy variables at 12 months after surgery is as follows:

  • Uncorrected visual activity (UCVA) 20/20 or better (74%); UCVA 20/40 or better (97%)
  • Mean refractive spherical equivalent (MRSE) ± 0.50 D (69%); MRSE ± 1.00 D (92%)
  • Greater than or equal to 2 lines loss best spectacle corrected visual acuity (0%); increased cylinder greater than or equal to 2.00 D (0%)
  • Corneal topography demonstrated that, while general flattening of the central cornea occurs, the normal positive asphericity of the cornea is maintained after placement of the ring and ring segments.
  • Transient dry eye may follow the placement of Intacs inserts, but the tear film quality returns within 1 week after surgery.

Future and Controversies

Future applications of Intacs microthin inserts technology include the following:

  • Myopia with astigmatism - Going beyond the range that has been approved by the FDA; currently, the upper limit is at -3.00 D spherical equivalent at the spectacle plane.
  • Astigmatism - Applications in patients with pure astigmatism; currently, the upper limit is at +1.00 D of astigmatism.
  • Presbyopia - In presbyopes and patients previously treated with LASIK or PRK
  • Therapeutic indications - The use of Intacs in patients with mild corneal ectasia not deemed to be candidates for LASIK or PRK
  • Therapeutic indications - By flattening the central corneal protrusion, intracorneal ring implantation is a promising new therapy for patients with early-to-moderate pellucid marginal degeneration (PMD) and who are intolerant of contact lenses.
  • Combination refractive procedures – Both the LASIK-Intacs method and the Intacs-LASIK method resulted in significant improvement in visual acuity and refraction based on limited experience. LASIK followed by Intacs may be the preferred procedure for reasons of safety, convenience, and lower induced cylinder.
  • Enhancement - The correction of residual myopia following maximum corneal sculpting with LASIK or PRK (posterior stromal bed too thin for further ablation); improving the conditions of patients with decreased nighttime visual function (including halos, induced myopia, and decreased contrast sensitivity) following LASIK and PRK, associated with constricted optical zones
  • Enhancement - Implantation of Intacs in eyes with myopic regression after LASIK and PRK resulted in a good refractive outcome and an improvement in uncorrected visual acuity.

 


More on Myopia, Intracorneal Rings

Overview: Myopia, Intracorneal Rings
Workup: Myopia, Intracorneal Rings
Treatment: Myopia, Intracorneal Rings
Follow-up: Myopia, Intracorneal Rings
Multimedia: Myopia, Intracorneal Rings
References
Further Reading
[ CLOSE WINDOW ]

References

  1. Alio J, Salem T, Artola A, et al. Intracorneal rings to correct corneal ectasia after laser in situ keratomileusis. J Cataract Refract Surg. Sep 2002;28(9):1568-74. [Medline].

  2. Alió JL, Artola A, Hassanein A, et al. One or 2 Intacs segments for the correction of keratoconus. J Cataract Refract Surg. May 2005;31(5):943-53. [Medline].

  3. Asbell PA, Ucakhan OO. Long-term follow-up of Intacs from a single center. J Cataract Refract Surg. Sep 2001;27(9):1456-68. [Medline].

  4. Asbell PA, Ucakhan OO, Durrie DS, et al. Adjustability of refractive effect for corneal ring segments. J Refract Surg. Nov-Dec 1999;15(6):627-31. [Medline].

  5. Assil KK. Intacs as an Enhancement Procedure. In: AAO Refractive Surgery Subspecialty Day Manual. 2000.

  6. Assil KK, Barrett AM, Fouraker BD, et al. One-year results of the intrastromal corneal ring in nonfunctional human eyes. Intrastromal Corneal Ring Study Group. Arch Ophthalmol. Feb 1995;113(2):159-67. [Medline].

  7. Assil KK, Quantock AJ, Barrett AM, et al. Corneal iron lines associated with the intrastromal corneal ring. Am J Ophthalmol. Sep 15 1993;116(3):350-6. [Medline].

  8. Azar RG, Holdbrook MJ, Lemp M, et al. Two-year corneal endothelial cell assessment following INTACS implantation. J Refract Surg. Sep-Oct 2001;17(5):542-8. [Medline].

  9. Baikoff G, Maia N, Poulhalec D, et al. [Diurnal variations of refraction and keratometry after intracorneal rings]. J Fr Ophtalmol. Mar 1999;22(2):169-75. [Medline].

  10. Barach D, Mortemousque B, Bertel F, et al. [Fluctuations in uncorrected visual acuity after refractive surgery using intra-stromal corneal rings]. J Fr Ophtalmol. Apr 1999;22(3):335-8. [Medline].

  11. Barbara A, Shehadeh-Masha'our R, Garzozi HJ. Intacs after laser in situ keratomileusis and photorefractive keratectomy. J Cataract Refract Surg. Sep 2004;30(9):1892-5. [Medline].

  12. Barbara A, Shehadeh-Masha'our R, Zvi F, et al. Management of pellucid marginal degeneration with intracorneal ring segments. J Refract Surg. May-Jun 2005;21(3):296-8. [Medline].

  13. Bourcier T, Borderie V, Laroche L. Late bacterial keratitis after implantation of intrastromal corneal ring segments. J Cataract Refract Surg. Feb 2003;29(2):407-9. [Medline].

  14. Boxer Wachler BS, Christie JP, Chandra NS, et al. Intacs for keratoconus. Ophthalmology. May 2003;110(5):1031-40. [Medline].

  15. Burris TE. Intrastromal corneal ring technology: results and indications. Curr Opin Ophthalmol. Aug 1998;9(4):9-14. [Medline].

  16. Burris TE, Ayer CT, Evensen DA, et al. Effects of intrastromal corneal ring size and thickness on corneal flattening in human eyes. Refract Corneal Surg. Jan-Feb 1991;7(1):46-50. [Medline].

  17. Burris TE, Baker PC, Ayer CT, et al. Flattening of central corneal curvature with intrastromal corneal rings of increasing thickness: an eye-bank eye study. J Cataract Refract Surg. 1993;19 Suppl:182-7. [Medline].

  18. Burris TE, Holmes-Higgin DK, Silvestrini TA. Lamellar intrastromal corneal tattoo for treating iris defects (artificial iris). Cornea. Mar 1998;17(2):169-73. [Medline].

  19. Burris TE, Holmes-Higgin DK, Silvestrini TA, et al. Corneal asphericity in eye bank eyes implanted with the intrastromal corneal ring. J Refract Surg. Sep-Oct 1997;13(6):556-67. [Medline].

  20. Chan SM, Khan HN. Reversibility and exchangeability of intrastromal corneal ring segments. J Cataract Refract Surg. Apr 2002;28(4):676-81. [Medline].

  21. Clinch TE, Lemp MA, Foulks GN, et al. Removal of INTACS for myopia. Ophthalmology. Aug 2002;109(8):1441-6. [Medline].

  22. Cochener B, Le Floch-Savary G, Colin J. [Excimer photorefractive keratectomy (PRK) versus intrastromal corneal ring segments (ICRS) for correction of low myopia]. J Fr Ophtalmol. Sep 2000;23(7):663-78. [Medline].

  23. Colin J, Cochener B, Savary G, et al. Correcting keratoconus with intracorneal rings. J Cataract Refract Surg. Aug 2000;26(8):1117-22. [Medline].

  24. Colin J, Cochener B, Savary G, et al. INTACS inserts for treating keratoconus: one-year results. Ophthalmology. Aug 2001;108(8):1409-14. [Medline].

  25. Colin J, Velou S. Implantation of Intacs and a refractive intraocular lens to correct keratoconus. J Cataract Refract Surg. Apr 2003;29(4):832-4. [Medline].

  26. Colin J, Velou S. Utilization of refractive surgery technology in keratoconus and corneal transplants. Curr Opin Ophthalmol. Aug 2002;13(4):230-4. [Medline].

  27. Davis EA, Hardten DR, Lindstrom RL. Laser in situ keratomileusis after intracorneal rings. Report of 5 cases. J Cataract Refract Surg. Dec 2000;26(12):1733-41. [Medline].

  28. Donnenfeld ED. Intacs vs LASIK for Low Myopia. In: AAO Refractive Surgery Subspecialty Day Manual. 2000.

  29. Duffey RJ, Leaming D. U.S. trends in refractive surgery: 2001 International Society of Refractive Surgery Survey. J Refract Surg. Mar-Apr 2002;18(2):185-8. [Medline].

  30. Durrie DS, Vande Garde TL. LASIK enhancements. Int Ophthalmol Clin. Summer 2000;40(3):103-10. [Medline].

  31. Edelhauser HF. The resiliency of the corneal endothelium to refractive and intraocular surgery. Cornea. May 2000;19(3):263-73. [Medline].

  32. Ertan A, Colin J. Intracorneal rings for keratoconus and keratectasia. J Cataract Refract Surg. Jul 2007;33(7):1303-14. [Medline].

  33. Ertan A, Kamburoglu G. Intacs implantation using a femtosecond laser for management of keratoconus: Comparison of 306 cases in different stages. J Cataract Refract Surg. Sep 2008;34(9):1521-6. [Medline].

  34. FDA. Intacs. Summary of safety and effectiveness. FDA. 1999.

  35. Fleming JF, Lovisolo CF. Intrastromal corneal ring segments in a patient with previous laser in situ keratomileusis. J Refract Surg. May-Jun 2000;16(3):365-7. [Medline].

  36. Fleming JF, Wan WL, Schanzlin DJ. The theory of corneal curvature change with the Intrastromal Corneal Ring. CLAO J. Apr-Jun 1989;15(2):146-50. [Medline].

  37. Fontana L, Parente G, Sincich A, Tassinari G. Deep anterior lamellar keratoplasty after intacs implantation in patients with keratoconus. Cornea. Jan 2009;28(1):32-5. [Medline].

  38. Gomez L, Chayet A. Laser in situ keratomileusis results after intrastromal corneal ring segments (Intacs). Ophthalmology. Oct 2001;108(10):1738-43. [Medline].

  39. Grabner G, Ruckhofer J, Tratter C, et al. [The intrastromal corneal ring (KeraVision Ring, ICR, ICRS). A modern method for correcting minor myopia]. Wien Med Wochenschr. 1997;147(12-13):309-21. [Medline].

  40. Guell JL. Are intracorneal rings still useful in refractive surgery?. Curr Opin Ophthalmol. Aug 2005;16(4):260-5. [Medline].

  41. Guell JL, Velasco F, Sanchez SI, et al. Intracorneal ring segments after laser in situ keratomileusis. J Refract Surg. Jul-Aug 2004;20(4):349-55. [Medline].

  42. Harr D. KeraVision begins implanting corneal reshaping device in blind eyes. Refract Corneal Surg. Sep-Oct 1991;7(5):343. [Medline].

  43. Hellstedt T, Makela J, Uusitalo R, et al. Treating keratoconus with intacs corneal ring segments. J Refract Surg. May-Jun 2005;21(3):236-46. [Medline].

  44. Hofling-Lima AL, Branco BC, Romano AC, et al. Corneal infections after implantation of intracorneal ring segments. Cornea. Aug 2004;23(6):547-9. [Medline].

  45. Holmes-Higgin DK, Baker PC, Burris TE, et al. Characterization of the aspheric corneal surface with intrastromal corneal ring segments. J Refract Surg. Sep-Oct 1999;15(5):520-8. [Medline].

  46. Holmes-Higgin DK, Burris TE. Corneal surface topography and associated visual performance with INTACS for myopia: phase III clinical trial results. The INTACS Study Group. Ophthalmology. Nov 2000;107(11):2061-71. [Medline].

  47. Holmes-Higgin DK, Burris TE, Lapidus JA, et al. Risk factors for self-reported visual symptoms with Intacs inserts for myopia. Ophthalmology. Jan 2002;109(1):46-56. [Medline].

  48. Ito M, Arai H, Fukumoto T, et al. INTACS before or after laser in situ keratomileusis: correction of thin corneas with moderately high myopia. J Refract Surg. Nov-Dec 2004;20(6):818-22. [Medline].

  49. Kamburoglu G, Ertan A. Intacs implantation with sequential collagen cross-linking treatment in postoperative LASIK ectasia. J Refract Surg. Sep 2008;24(7):S726-9. [Medline].

  50. Kessler D, El-Shiaty AF, Wachler BS. Evaluation of tear film following Intacs for myopia. J Refract Surg. Mar-Apr 2002;18(2):127-9. [Medline].

  51. Kymionis GD, Aslanides IM, Siganos CS, et al. Intacs for early pellucid marginal degeneration. J Cataract Refract Surg. Jan 2004;30(1):230-3. [Medline].

  52. Kymionis GD, Siganos CS, Kounis G, et al. Management of post-LASIK corneal ectasia with Intacs inserts: one-year results. Arch Ophthalmol. Mar 2003;121(3):322-6. [Medline].

  53. Levinger S, Pokroy R. Keratoconus managed with intacs: one-year results. Arch Ophthalmol. Oct 2005;123(10):1308-14. [Medline].

  54. Linebarger EJ, Song D, Ruckhofer J, et al. Intacs: the intrastromal corneal ring. Int Ophthalmol Clin. Summer 2000;40(3):199-208. [Medline].

  55. Loarie TM. The migration offshore of U.S. medical technology innovation--what it means for U.S. physicians. J Refract Surg. Mar-Apr 1997;13(2):176-84. [Medline].

  56. Loughnan MS, Robinson D, Sullivan L. Mechanical methods in refractive corneal surgery. Curr Opin Ophthalmol. Aug 1996;7(4):41-6. [Medline].

  57. Lovisolo CF, Fleming JF. Intracorneal ring segments for iatrogenic keratectasia after laser in situ keratomileusis or photorefractive keratectomy. J Refract Surg. Sep-Oct 2002;18(5):535-41. [Medline].

  58. McDonald JE, Deitz DJ. Removal of Intacs with a fractured positioning hole. J Refract Surg. Mar-Apr 2004;20(2):182-3. [Medline].

  59. Mularoni A, Torreggiani A, di Biase A, et al. Conservative treatment of early and moderate pellucid marginal degeneration: a new refractive approach with intracorneal rings. Ophthalmology. Apr 2005;112(4):660-6. [Medline].

  60. Nio YK, Jansonius NM, Wijdh RH, et al. Effect of methods of myopia correction on visual acuity, contrast sensitivity, and depth of focus. J Cataract Refract Surg. Nov 2003;29(11):2082-95. [Medline].

  61. Nose W, Neves RA, Burris TE, et al. Intrastromal corneal ring: 12-month sighted myopic eyes. J Refract Surg. Jan-Feb 1996;12(1):20-8. [Medline].

  62. Nosé W, Neves RA, Schanzlin DJ, et al. Intrastromal corneal ring--one-year results of first implants in humans: a preliminary nonfunctional eye study. Refract Corneal Surg. Nov-Dec 1993;9(6):452-8. [Medline].

  63. Patel S, Marshall J, Fitzke FW 3rd. Model for deriving the optical performance of the myopic eye corrected with an intracorneal ring. J Refract Surg. Jul-Aug 1995;11(4):248-52. [Medline].

  64. Pokroy R, Levinger S, Hirsh A. Single Intacs segment for post-laser in situ keratomileusis keratectasia. J Cataract Refract Surg. Aug 2004;30(8):1685-95. [Medline].

  65. Quantock AJ, Assil KK, Schanzlin DJ. Electron microscopic evaluation of intrastromal corneal rings explanted from nonfunctional human eyes. J Refract Corneal Surg. Mar-Apr 1994;10(2):142-8. [Medline].

  66. Rapuano CJ, Sugar A, Koch DD, et al. Intrastromal corneal ring segments for low myopia: a report by the American Academy of Ophthalmology. Ophthalmology. Oct 2001;108(10):1922-8. [Medline].

  67. Rodriguez-Prats J, Galal A, Garcia-Lledo M, et al. Intracorneal rings for the correction of pellucid marginal degeneration. J Cataract Refract Surg. Jul 2003;29(7):1421-4. [Medline].

  68. Rosen E, Kowalewski E. Instrument for initiating the corneal intrastromal channel for the insertion of Intacs. J Cataract Refract Surg. Sep 2001;27(9):1356-8. [Medline].

  69. Ruckhofer J, Bohnke M, Alzner E, et al. Confocal microscopy after implantation of intrastromal corneal ring segments. Ophthalmology. Dec 2000;107(12):2144-51. [Medline].

  70. Ruckhofer J, Linebarger EJ, Schanzlin DJ. Goldmann applanation tonometry after intacs corneal ring segments(1). J Cataract Refract Surg. Sep 2000;26(9):1332-8. [Medline].

  71. Ruckhofer J, Twa MD, Schanzlin DJ. Clinical characteristics of lamellar channel deposits after implantation of intacs. J Cataract Refract Surg. Oct 2000;26(10):1473-9. [Medline].

  72. Schanzlin DJ, Asbell PA, Burris TE, et al. The intrastromal corneal ring segments. Phase II results for the correction of myopia. Ophthalmology. Jul 1997;104(7):1067-78. [Medline].

  73. Shehadeh-Masha'our R, Modi N, Barbara A, et al. Keratitis after implantation of intrastromal corneal ring segments. J Cataract Refract Surg. Aug 2004;30(8):1802-4. [Medline].

  74. Shetty R, Kurian M, Anand D, Mhaske P, Narayana KM, Shetty BK. Intacs in advanced keratoconus. Cornea. Oct 2008;27(9):1022-9. [Medline].

  75. Siganos CS, Kymionis GD, Astyrakakis N, et al. Management of corneal ectasia after laser in situ keratomileusis with INTACS. J Refract Surg. Jan-Feb 2002;18(1):43-6. [Medline].

  76. Siganos CS, Kymionis GD, Kartakis N, et al. Management of keratoconus with Intacs. Am J Ophthalmol. Jan 2003;135(1):64-70. [Medline].

  77. Sugar A. Correction of spherical myopia with a single 150-degree intrastromal corneal ring segment. J Cataract Refract Surg. May 2004;30(5):1127-9. [Medline].

  78. Tran DB, Zadok D, Carpenter M, et al. Intraocular pressure measurement in patients with intrastromal corneal ring segments. J Refract Surg. Jul-Aug 1999;15(4):441-3. [Medline].

  79. Twa MD, Hurst TJ, Walker JG, et al. Diurnal stability of refraction after implantation with intracorneal ring segments. J Cataract Refract Surg. Apr 2000;26(4):516-23. [Medline].

  80. Twa MD, Karpecki PM, King BJ, et al. One-year results from the phase III investigation of the KeraVision Intacs. J Am Optom Assoc. Aug 1999;70(8):515-24. [Medline].

  81. Ucakhan OO, Tello C, Liebmann JM, et al. Optical coherence tomography of Intacs. J Cataract Refract Surg. Oct 2001;27(10):1535. [Medline].

[ CLOSE WINDOW ]

Further Reading

[ CLOSE WINDOW ]

Keywords

Intacs microthin prescription inserts, Intacs, Intacs inserts, intracorneal rings, intrastromal corneal rings, ICR, intrastromal corneal ring segments, ICRS, refractive keratotomy, RK, photorefractive keratectomy, PRK, laser-assisted in situ keratomileusis, LASIK, myopia, astigmatism, refractive surgery, keratoconus

[ CLOSE WINDOW ]

Contributor Information and Disclosures

Author

Manolette R Roque, MD, MBA, DPBO, FPAO, President and CEO, Chief of Service, Ocular Immunology and Uveitis, Consulting Staff, Cornea and Refractive Surgery, Eye Republic Ophthalmology Clinic; General Manager, Ophthalmic Consultants Philippines Co; Consulting Staff, CME Liaison, Section Chief of Ocular Immunology and Uveitis, Department of Ophthalmology, Asian Hospital and Medical Center
Manolette R Roque, MD, MBA, DPBO, FPAO is a member of the following medical societies: American Academy of Ophthalmic Executives, American Academy of Ophthalmology, American Society of Cataract and Refractive Surgery, American Society of Ophthalmic Administrators, American Uveitis Society, International Ocular Inflammation Society, Philippine Medical Association, Philippine Ocular Inflammation Society, and Philippine Society of Cataract and Refractive Surgery
Disclosure: Nothing to disclose.

Coauthor(s)

Barbara L Roque, MD, Full Partner, Ophthalmic Consultants Philippines Co, Chief of Service, Pediatric Ophthalmology and Strabismus, Consulting Staff, Orbit and Eye Plastics, Eye Republic Ophthalmology Clinic
Disclosure: Nothing to disclose.

Ruben Limbonsiong, MD, Chief of Service, Refractive Surgery Service and Vision Laser Center, St. Luke's Medical Center; Program Director, Clinical Assistant Professor, Department of Ophthalmology, University of the Philippines at Manila
Ruben Limbonsiong, MD is a member of the following medical societies: American Academy of Ophthalmology and American Society of Cataract and Refractive Surgery
Disclosure: Nothing to disclose.

Roberto Pineda, ll, MD, Scholar, The Academy at Harvard Medical School; Director, Refractive Surgery Service, Massachusetts Eye and Ear Infirmary
Roberto Pineda, ll, MD is a member of the following medical societies: American Academy of Ophthalmology and American Society of Cataract and Refractive Surgery
Disclosure: Nothing to disclose.

Medical Editor

Daniel S Durrie, MD, Director, Department of Ophthalmology, Division of Refractive Surgery, University of Kansas Medical Center
Daniel S Durrie, MD is a member of the following medical societies: American Academy of Ophthalmology and Association for Research in Vision and Ophthalmology
Disclosure: Nothing to disclose.

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: Nothing to disclose.

Managing Editor

Louis E Probst, MD, Medical Director of Refractive Surgery, Chicago, Madison, Milwaukee, and Windsor Centers, TLC the Laser Eye Centers
Louis E Probst, MD is a member of the following medical societies: American Academy of Ophthalmology, American Society of Cataract and Refractive Surgery, and International Society of Refractive Surgery
Disclosure: Nothing to disclose.

CME Editor

Lance L Brown, OD, MD, Ophthalmologist, Affiliated With Freeman Hospital and St John's Hospital, Regional Eye Center, Joplin, Missouri
Disclosure: Nothing to disclose.

Chief Editor

Hampton Roy Sr, MD, Associate Clinical Professor, Department of Ophthalmology, University of Arkansas for Medical Sciences
Hampton Roy Sr, MD is a member of the following medical societies: American Academy of Ophthalmology, American College of Surgeons, and Pan-American Association of Ophthalmology
Disclosure: Nothing to disclose.

 
 
HONcode

We subscribe to the
HONcode principles of the
Health On the Net Foundation

All material on this website is protected by copyright, Copyright© 1994- by Medscape.
This website also contains material copyrighted by 3rd parties.

DISCLAIMER: The content of this Website is not influenced by sponsors. The site is designed primarily for use by qualified physicians and other medical professionals. The information contained herein should NOT be used as a substitute for the advice of an appropriately qualified and licensed physician or other health care provider. The information provided here is for educational and informational purposes only. In no way should it be considered as offering medical advice. Please check with a physician if you suspect you are ill.