Objective: To evaluate the long-term clinical outcomes (minimum follow-up period of 2 years) of accelerated crosslinking (CXL) at 18 mW/cm2 for 5 minutes, in patients with progressive keratoconus. Material and Methods: Thirty five eyes of 35 patients with progressive keratoconus who underwent accelerated CXL were included. Topographical measurements were obtained using a rotating Scheimpflug camera (Sirius). Flat Keratometry (K) value (K1), steep K value (K2), average K value (avgK), topographic cylindrical value (Cyl), apical keratoscopy front (AKf or Kmax), apical keratoscopy back (AKb), symmetry index front (SIf), symmetry index back (SIb), central corneal thickness (CCT), thinnest point of the cornea (Thin), and total corneal volume (CV) were recorded from the topography data generated by the Scheimpflug system. Results: The uncorrected and best corrected visual acuity of the patients had begun to increase significantly after 6 months postoperatively (p=0.014 and p=0.0001, respectively) and continued to improve in the 12th and 24th months (p<0.05 for all). There was a statistically significant but temporary increase in keratometric values of K2, avgK and AKf at 1 month postoperative (p=0.0001, p=0.008, and p=0.001, respectively), but K2 and avgK did not show any statistically significant difference in the other follow-up visits (p>0.05 for all). Flat keratometry value decreased significantly at 24 months (p=0.029) and, AKf improved significantly at 12 and 24 months (p=0.029 and p=0.001, respectively). Conclusion: The accelerated CXL procedure (18 mW/cm2 for 5 minutes) is effective in preventing keratoconus progression with increased visual acuity and stabilization in keratometric values after the 2-year follow-up.
Keywords: Corneal collagen crosslinking; corneal topography; keratoconus
Amaç: İlerleyici keratokonus hastalarında 5 dakika 18 mW/cm2 hızlandırılmış korneal kollajen çapraz bağlama (KÇB) tedavisinin uzun dönem (minimum takip süresi 2 yıl) klinik sonuçlarını değerlendirmek Gereç ve Yöntemler: İlerleyici keratokonus nedeniyle hızlandırılımış KÇB teadvisi yapılan 35 hastanın 35 gözü çalışmaya alındı. Topografik ölçümler dönen Scheimpflug kamera (Sirius) kullanılarak yapıldı. Düz Keratometri (K) değeri (K1), dik K değeri (K2), ortalama K değeri (avgK), topografik silindirik değer (Cyl), ön apikal keratoskopi (AKf veya Kmax), arka apikal keratoskopi (AKb), ön simetri indeksi (SIf), arka simetri indeksi (SIb), merkezi kornea kalınlığı (SKK), korneanın en ince noktası (Thin) ve toplam kornea hacmi (CV), Scheimpflug sistemi tarafından oluşturulan topografi verilerinden kaydedildi. Bulgular: Hastaların düzeltilmemiş ve en iyi düzeltilmiş görme keskinliği ameliyat sonrası 6 ay sonra anlamlı şekilde artmaya başlamış (sırasıyla p=0,014 ve p=0,0001), 12. ve 24. aylarda iyileşmeye devam etmiştir (hepsi için p<0,05). Ameliyat sonrası 1. ayda K2, avgK ve AKf'nin keratometrik değerlerinde istatistiksel olarak anlamlı ancak geçici bir artış vardı (sırasıyla p=0,0001, p=0,008 ve p=0,001), ancak K2 ve avgK değerlerinde diğer takiplerde istatistiksel olarak anlamlı bir fark bulunmadı (tümü için p>0,05). Düz Keratometri değeri, 24. ayda önemli ölçüde azaldı (p=0,029) ve AKf, 12. ve 24. ayda önemli ölçüde düzelme gösterdi (sırasıyla, p=0,029 ve p=0,001). Sonuç: Hızlandırılmış (5 dakika 18 mW/cm2) KÇB yöntemi iki yıllık takip sonunda artan görme keskinliği ve keratometrik değerlerde stabilizasyon ile keratokonusun ilerlemesinin önlenmesinde etkilidir.
Anahtar Kelimeler: Korneal kollajen çapraz bağlama; korneal topografi; keratokonus
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