INTRASTROMAL CORNEAL RING SEGMENTS (ICRS, KERAVISION RING, INTACSTM): CLINICAL RESULTS AFTER 2 YEARS

  • Josef Ruckhofer Landesklinik für Augenheilkunde und Optometrie Landeskliniken Salzburg Müllner Hauptstr. 48 Salzburg Avstrija
  • Josef Stoiber Landesklinik für Augenheilkunde und Optometrie Landeskliniken Salzburg Müllner Hauptstr. 48 Salzburg Avstrija
  • Egon Alzner Landesklinik für Augenheilkunde und Optometrie Landeskliniken Salzburg Müllner Hauptstr. 48 Salzburg Avstrija
  • Günther Grabner Landesklinik für Augenheilkunde und Optometrie Landeskliniken Salzburg Müllner Hauptstr. 48 Salzburg Avstrija
Keywords: intrastromal corneal ring segments, ICRS, KeraVision ring, IntacsTM, myopia, stability-reversibility-adjustability

Abstract

Background. Since 1996 Intrastromal Corneal Ring Segments (IntacsTM, KeraVision, Inc.Fremont, Ca, USA) have been used for the correction of mild to moderate myopia at the Salzburg Eye Clinic. Aim of this study was to evaluate the stability, reversibility and adjustability for this new method.

Patients and methods. Our experience and final results of 54 surgeries – 30 eyes with a minimum follow-up of 2 years – as well as the potential reversibility (3 explantations, 2 of them followed by PRK) and adjustability (3 exchanges) are reported in detail.

Results. None of the eyes lost more than one line in BSCVA (in 14 of 30 eyes the BSCVA improved). 73% (22/30) eyes reached an UCVA of 1.0 or better, 47% (14/30) eyes of 1.25 or better. After 2 years 47% (14/30) eyes were within ± 0.5 Dsph of the attempted correction. We observed no significant intraor postoperative complications. After ICRS removal the refractive data returned within ± 0.75 Dsph (MRSE) and ± 0.5 Dsph (mean keratometry) of preoperative values, respectively. Patients with an ICRS exchange obtained an improved visual acuity between 0.8 and 1.0, gaining between 2 to 4 lines.

Conclusions. With the follow-up period of 2 years the ICRS seem to provide a very stable correction of low to moderate myopia. The procedure is reversible to a large extent, potentially adjustable (within certain limits) and carries a minimal risk only. After explantation PRK can be performed with good visual results.

Downloads

Download data is not yet available.

References

Höh H, Rehfeldt K, Görges W. Der intrakorneale Ring zur Myopie-Korrektur – die erste reversible Alternative in der refraktiven Chirurgie. Contactologia 1999; 21: 172–91.

Ruckhofer J, Alzner E, Grabner G. Der intrastromale korneale Ring (KeraVision Ring, ICR, ICRS) – Eine neue, reversible Methode zur Korrektur der niedrigen Myopie. Entwicklung, kritischer Vergleich mit RK, PRK, eigene refraktive Ergebnisse und Nebenwirkungen der ersten 25 Eingriffe. Spektrum Augenheilkd 1997; 11: 247–54.

Ruckhofer J, Alzner E, Grabner G. Der intrastromale korneale Ring Segmente (ICRS, KeraVision Ring). Einjahresergebnisse der ersten 25 Eingriffe. Klin Monatsbl Augenheilkd 1998; 213: 147–53.

Thibos LN, Wheeler W, Horner D. Power vectors: An application of Fourier analysis to the description and statistical analysis of refractive error. Optom Vis Sci 1997; 74: 367–75.

Assil KK, Quantock AJ, Barrett AM, Schanzlin DJ. Corneal iron lines associated with the intrastromal corneal ring. Am J Ophthalmol 1993; 116: 350–6.

Fink AM, Gore C, Rosen ES. Corneal changes associated with intrastromal corneal ring segments. Arch Ophthalmol 1999; 117: 282–2.

Grabner G. Eine neue, zentrale, epitheliale Eisenablagerung nach Epikeratophakie zur Korrektur höhergradiger Myopie. Klin Monatsbl Augenheilkd 1987; 190: 424–7.

Koenig SB, McDonald MB, Yamaguchi T, Friedlander M, Ishii Y. Corneal iron lines after refractive keratoplasty. Arch Ophthalmol 1983; 101: 1862–5.

Krueger RR, Tersi I, Seiler T. Corneal iron line associated with steep central islands after photorefractive keratectomy. J Refract Surg 1997; 13: 401–3.

Probst LE, Almasswary MA, Bell J. Pseudo-Fleischer ring after hyperoptic laser in situ mileusis. J Cataract Refract Surg 1999; 25: 868–70.

Seiler T, Holschbach A. Central corneal iron deposit after photorefractive keratectomy. Ger J Ophthalmol 1993; 2: 143–5.

Twa MD, Karpecki PM, King BJ, Linn SH, Durrie DS, Schanzlin DJ. One-year results for the phase III investigation of the KeraVision Intacs. J Am Optom Assoc 1999; 70: 515–24.

Burris TE. Intrastromal corneal ring technology: results and indications. Curr Opin Ophthalmol 1998; 9: 9–14.

Holmes-Higgin DK, Burris TE, Asbell PA, Durrie DS, Schanzlin DJ. Topographic predicted corneal acuity with intrastromal corneal ring segments. J Refract Surg 1999; 15: 324–30.

Krueger RR, Burris TE. Intrastromal corneal ring technology. Int Ophthal Clin 1996; 4: 89–106.

Nosé W, Neves RA, Burris TE, Schanzlin DJ, Belfort R Jr. Intrastromal corneal ring: 12-month sighted myopic eyes. J Refract Surg 1996; 12: 1–28.

Nosé W, Neves RA, Schanzlin DJ, Belfort R Jr. Intrastromal corneal ring – one year results of first implants in humans: a preliminary nonfunctional eye study. Refract Corneal Surg 1993; 9: 452–8.

Quantock AJ, Kincaid MC, Schanzlin DJ. Stromal healing following explantation of an ICR (Intrastromal Corneal Ring) from a nonfunctional eye. Arch Ophthalmol 1995; 113: 208–9.

Tran DB, Zadok D, Carpenter M, Korn TS, Twa M, Schanzlin DJ. Intraocular pressure measurment in patients with intrastromal corneal ring segments. J Refract Surg 1999; 15: 441–3.

Holmes-Higgin DK, Baker PC, Burris TE, Silvestrini TA. Characterization of the aspheric corneal surface with intrastromal corneal ring segments. J Refract Surg 1999; 15: 520–8.

Asbell PA, Ucakhan OO, Durrie DS, Lindstrom RL. Adjustability of refractive effect for corneal ring segments. J Refract Surg 1999; 15: 627–31.

Grabner G, Ruckhofer J, Tratter C, Alzner E. Der intrastromale corneale Ring (KeraVision Ring, ICR, ICRS). Eine moderne Methode zur Korrektur der geringen Myopie. Wien Med Wschr 1997; 147: 309–21.

Nagy Z, Krasznai G, Modis L Jr, Sefcsik I, Furka I, Miko I. Intrastromal corneal ring, a new refractive surgical technique to decrease myopia. Experimental and clinical results. Acta Chir Hung 1997; 36: 248–50.

Bisantis C, Bisantis F. Intrastromal segmental perioptic implants for high myopia. Invest Ophthalmol Vis Sci 1995; 36: S 998 (4571).

Midena E, Bisantis C, Bisantis F, Valenti F, Provenzano F, Mancini A. Visual performance and visual side effects after insertion after corneal intrastromal perioptic implants. Invest Ophthalmol Vis Sci 1998; 39: S 74 (338).

How to Cite
1.
Ruckhofer J, Stoiber J, Alzner E, Grabner G. INTRASTROMAL CORNEAL RING SEGMENTS (ICRS, KERAVISION RING, INTACSTM): CLINICAL RESULTS AFTER 2 YEARS. TEST ZdravVestn [Internet]. 1 [cited 5Aug.2024];71. Available from: http://vestnik-dev.szd.si/index.php/ZdravVest/article/view/1718
Section
Professional Article