J Korean Ophthalmol Soc.  2009 Oct;50(10):1505-1509. 10.3341/jkos.2009.50.10.1505.

Intracorneal Ring Segment Implantation for the Management of Keratoconus: Short-Term Safety and Efficacy

• Kim HS
• Lee TH
• Lee KH

• KMID: 2212767
• DOI: http://doi.org/10.3341/jkos.2009.50.10.1505

Abstract

PURPOSE
To assess the safety and efficacy of intracorneal ring segment (Intacs ring) implantation in managing keratoconus.
METHODS
This retrospective case series comprised of 11 keratoconic eyes (11 patients) had Intacs ring (Addition Technology, Inc, California, USA) implantation. The main outcome measures were best corrected visual acuity, refraction, keratometry, topography, and pachymetry. Patients were examined before Intacs ring implantation as well as one week, one, three, and six months postoperatively.
RESULTS
The mean best corrected visual acuity improved from 0.60+/-0.33 logMAR preoperatively to 0.39+/-0.23 logMAR six months postoperatively (p>0.05) and the mean corneal thickness, from 432.82+/-41.17 micrometer preoperatively to 448.00+/-62.27 micrometer at six months (p>0.05). The mean cylinder improved from -5.36+/-2.70D preoperatively to -2.50+/-1.66D six months postoperatively (p<0.05) and the mean keratometry, from 47.99+/-2.38D to 42.83+/-1.72D at six months (p<0.05). In addition, the mean spherical equivalent improved from -6.64+/-3.49D preoperatively to -3.66+/-3.37D six months postoperatively (p<0.05). One eye had a risk of ring exposure, but the others had no significant complications.
CONCLUSIONS
Intacs ring implantation appears to be effective in improving cylinder, spherical equivalent, and keratometry in patients with keratoconus.

Keyword

Intacs; Intracorneal ring segment; Keratoconus

MeSH Terms

California
Eye
Humans
Keratoconus
Outcome Assessment (Health Care)
Retrospective Studies
Visual Acuity

Reference

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