Long-term follow-up results of corneal collagen cross-linking in keratoconus

Abstract

Objective: To evaluate the changes in corneal parameters (keratometry, corneal thickness, topography indices) after corneal collagen cross-linking in keratoconus.

Methods: The medical records of 6 patients who underwent corneal collagen cross-linking treatment for keratoconus and have been followed-up for a minimum of 24 months were recruited. Best corrected visual acuity (BCVA), maximum keratometry (Kmax), central corneal thickness (CCT) values and corneal topography indices: index of surface variance (ISV), index of vertical asymmetry (IVA), keratoconus index (KI), central keratoconus index (CKI), minimum radius of curvature (Rmin), index of height asymmetry (IHA), and index of height decentralisation (IHD) were recorded.

Results: The mean preoperative Kmax value was 46.67±4.15 (43.30-57.10) D and the mean Kmax value at the final postoperative visit was 45.41±2.95 (43.00-53.20) D. Mean preoperative CCT was 494.70±33.69 (438-537) µm and final postoperative mean CCT was 495.60±34.99 (433-539) µm. The deterioration in corneal topography indices stopped during the follow-up period of each case.

Conclusion: Stopping the deterioration of corneal parameters in keratoconus is the desired outcome after cross-linking treatment. Our results found an improvement or at least stabilization in all topography indices in keratoconus patients. J Clin Exp Invest 2015; 6 (4): 343-350

Key words: Keratoconus, corneal collagen cross-linking, corneal topography

Keywords

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Keratokonusta korneal kollajen çapraz-bağlama tedavisinin uzun dönem sonuçları

Öz

Amaç: Keratokonusta kornea kollajen çapraz bağlama sonrası kornea parametreleri (keratometre, kornea kalınlığı, topografi indeksleri) değişikliklerini değerlendirmek.Yöntemler: Keratokonus için korneal kollajen çapraz bağlama tedavisi uygulanan ve en az 24 ay takip edilen 6 hastanın tıbbi kayıtları çalışmaya alındı. En iyi düzeltilmiş görme keskinliği (EİDGK), maksimum keratometri (Kmax), santral kornea kalınlığı (SKK) ve korneal topografi indeksleri: Yüzey Varyans indeksi (ISV), dikey asimetri indeksi (IVA), keratokonus indeksi (Kİ), merkez keratokonus indeksi (CKI), minimum eğrilik yarıçapı (Rmin), yükseklik asimetrisi indeksi (IHA) ve yükseklik desantralizasyon indeksi (İHD) kaydedildi.Bulgular: Ameliyat öncesi Kmax değeri 46,67±4,15 (43.30-57.10) D ve ameliyat sonrası nihai ziyarette ortalama Kmax değeri 45.41±2.95 (43.00-53.20) D. Preoperatif SKK 494,70±33,69 µm idi ve nihai postoperatif ortalama SKK 495,60±34,99 µm idi. Her vakada korneal topografi indekslerindeki bozulma takip süresi boyunca durdu.Sonuç: Keratokonusta kornea parametrelerinin bozulmasını durdurmak çapraz bağlama tedavisinden sonra arzu edilen sonuçtur. Bizim çalışmamızın sonucunda keratokonus hastalarının tüm topografi indekslerinde iyileşme veya en azından stabilite saptanmıştır

Anahtar Kelimeler

• Keratokonus, korneal kollajen çapraz bağlama, kornea topografisi

Kaynakça

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