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Efficacy and safety of intracorneal allogenic ring segment implantation in keratoconus: 1-year results

Eye volume 37, pages 3807–3812 (2023)Cite this article

Subjects

Abstract

Background

To evaluate the safety and efficacy of corneal allogenic intrastromal ring segments in the management of keratoconus patients.

Methods

The retrospective, nonrandomized, interventional case series consisted of 65 keratoconic eyes of 49 consecutive patients who had ring segment-shaped corneal allografts (KeraNatural®) implanted in intrastromal tunnels created using a femtosecond laser. The main outcome measures were uncorrected visual acuity (UCVA), corrected distant visual acuity (CDVA), refraction, keratometry, and pachymetry. Computed tomography scans of the corneal surfaces were also performed preoperatively as well as 3, 6 and 12 months postoperatively.

Results

Mean age was 29.5 ± 7.3 years (median 29, range: 20–52 years). The mean UCVA improved from 0.91 ± 0.50 logMAR preoperatively to 0.40 ± 0.24 logMAR postoperatively at 6 month follow-up (p < 0.01) and the mean CDVA improved from 0.87 ± 0.20 logMAR preoperatively to 0.27 ± 0.06 logMAR postoperatively (p < 0.01). The mean spherical equivalent improved from −8.82 ± 4.57 to −3.45 ± 4.81D (p < 0.01). Average Keratometry decreased from 49.23 ± 5.22 preoperatively to 45.63 ± 4.89 D postoperatively (p < 0.01). Mean anterior and posterior maximum elevation were also decreased significantly (p < 0.01). In one patient, dislocation of the graft towards the tunnel incision site and dehiscense at the tunnel entrance were observed in the first week of the operation. Yellow-white deposits were observed in the segment tunnels in five cases after 6 months.

Conclusion

This study demonstrated that implantation of corneal allograft ring segments is a viable alternative treatment for keratoconus with safety and good visual results.

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Fig. 1: Peroperative and postoperative anterior segment images.
Fig. 2: Comparison of vision gain and vision improvement of patients after surgery.

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Data availability

Anonymised data for this study is available from the corresponding author upon reasonable request.

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Authors and Affiliations

  1. Faculty of Medicine, Ophthalmology Department, Istanbul Medipol University, Istanbul, Turkey

    Senay Asik Nacaroglu, Fatma Feyza Nur Keskin Perk, Cafer Tanriverdi & Aylin Kilic

  2. Şişli Hamidiye Etfal Training and Research Hospital, Department of Ophthalmology, University of Health Sciences, Istanbul, Turkey

    Elif Ceren Yesilkaya

  3. Ophthalmology Department, Augenzentrum am St. Franziskus Hospital, Munster, Germany

    Suphi Taneri

Authors
  1. Senay Asik Nacaroglu
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  2. Elif Ceren Yesilkaya
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  3. Fatma Feyza Nur Keskin Perk
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  4. Cafer Tanriverdi
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  5. Suphi Taneri
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  6. Aylin Kilic
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Contributions

Concept—SAN, ECY, AK; Design—SAN, ECY, FK, CT; Supervision—ST, CT, AK; Funding—SAN,CT,AK; Materials—SAN, FK, CT, AK; Data Collection and/or processing– SAN, FK, CT; Analysis &/or interpretation— SAN, ECY, ST, AK, Literature search– SAN, ECY, ST, AK; Writing—SAN, ECY, AK; Critical review– SAN, ECY, FK, CT, ST, AK.

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Correspondence to Senay Asik Nacaroglu.

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Competing interests

AK is a consultant of KeraNatural. The remaining authors have no conflicts of interest to disclose.

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Informed consent was obtained for the use of patient’s images.

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Nacaroglu, S.A., Yesilkaya, E.C., Perk, F.F.N.K. et al. Efficacy and safety of intracorneal allogenic ring segment implantation in keratoconus: 1-year results. Eye 37, 3807–3812 (2023). https://doi.org/10.1038/s41433-023-02618-5

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  • DOI: https://doi.org/10.1038/s41433-023-02618-5

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