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Published on: November 12, 2015
Intracorneal ring segments for keratoconus correction: long-term follow-up
Jorge L Alió1, Mohamed H Shabayek, Alberto Artola
1Department of Cornea and Refractive Surgery, Instituto Oftalmológico de Alicante, Vissum, Spain. jlalio@vissum.com
Journal of Cataract and Refractive Surgery
|July 4, 2006
Summary
Intracorneal ring segments (Intacs) improved vision and reduced keratoconus severity up to 36 months. While initial K-values decreased, they later increased significantly but remained below preoperative levels, indicating stable long-term results.
Area of Science:
- Ophthalmology
- Corneal Surgery
- Vision Correction
Background:
- Keratoconus is a progressive corneal ectasia leading to visual impairment.
- Intracorneal ring segments (Intacs) are used to improve visual acuity and regularize the corneal shape.
- Long-term outcomes and stability of Intacs implantation for keratoconus require further evaluation.
Purpose of the Study:
- To assess the long-term efficacy and stability of Intacs implantation in correcting keratoconus.
- To evaluate changes in visual acuity and corneal topography after Intacs implantation.
Main Methods:
- Retrospective study of 13 eyes with keratoconus treated with Intacs.
- Outcomes assessed at 6, 12, 24, 36, and 48 months postoperatively.
- Key metrics included best spectacle-corrected visual acuity (BSCVA) and keratometric values (I-S asymmetry, K-value).
Main Results:
- Mean BSCVA improved significantly from 0.46 preoperatively to 0.66 postoperatively (P<0.001).
- Mean inferior-superior (I-S) asymmetry decreased by 2.81 D (P<0.02), and mean K-value decreased by 3.13 D (P<0.001).
- No significant differences in BSCVA or I-S asymmetry were observed between 6 and 36 months, indicating stability. However, K-values increased significantly by 1.67 D at 36 months (P<0.002).
Conclusions:
- Intacs implantation offers stable visual and topographic improvements for keratoconus up to 36 months.
- The procedure effectively enhances BSCVA and reduces corneal irregularity.
- While K-values showed an increase at 36 months, they did not revert to initial preoperative levels.
