Corneal Collagen Cross-Linking Treatment (Cxl) in Keratoconus

Öz

Purpose: To evaluate the safety and efficiency of Riboflavin and Ultraviole A (UVA) supported corneal collagen crosslinking treatment (CXL) in the keratoconic eyes.

Materials and Methods: One hundred nineteen eyes of 71 patients with progressive keratoconus were included in this prospective study. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction, slit lamp examination, corneal topography, contrast sensitivity,central corneal thickness (CCT) with ultrasound pachymeter were evaluated at baseline and at 1,3,6 and 12 months follow-up.

Results: The mean age of the patients was 19.4±3.5 years. There was a mean of 1 snellen line improvement in both UDVA and CDVA (P=0.01). No patient lost 2 or more snellen lines of CDVA. At month-12 follow-up, mean manifest refraction spherical equivalent and mean keratometry readings showed a significant decrease of 1.13 and 0.41 diopters (P=0.04). The CCT decreased significantly during the first 3 months (P<0.05). Sight threatening complications were not encountered in any patient eye.

Conclusion: Corneal collagen crosslinking seems to be safe and effective in keratoconic eyes. The visual acuity may increase and progression was not encountered during 1 year follow-up.

Anahtar Kelimeler

• Crosslinking,Ectasia,Keratoconus,Cornea,Riboflavin

Keratokonusta Korneal Kollajen Çapraz Bağlanma Tedavisi (Cxl)

Öz

Amaç: Keratokonuslu olgularda riboflavin ve ultraviole A (UVA) destekli korneal kollajen çapraz bağlanma (CXL) tedavisinin güvenilirlik ve etkinliğinin değerlendirilmesi.

Gereç ve Yöntem: Progressif keratokonus tanısıyla takip edilen, 71 hastanın 119 gözü bu prospektif çalışmaya dahil edildi. Çalışmaya katılan tüm hastalardan CXL öncesi ve 1, 3, 6 ve 12. ay kontrollerinde; düzeltilmemiş görme keskinliği (UDVA), en iyi düzeltilmiş görme keskinliği (CDVA), manifest refraksiyon, biyomikroskopik muayene, kornea topografisi, ultrasonik pakimetre ile santral kornea kalınlığı ölçümü (SKK).

Bulgular: Olguların yaş ortalaması 19.43.5 yıldı. Takip süresi sonunda UDVA ve CDVA’da ortalama 1 snellen sırası artış saptandı (P=0.001). Olguların hiçbirinde CDVA’da 2 veya daha fazla snellen sırası azalma görülmedi. Son kontrolde, manifest refraksiyon sferik eşdeğeri ve ortalama keratometrik değerlerde, CXL öncesine göre 1.13 D ve 0.41 D anlamlı azalma saptandı (P=0.04). İlk 3 ayda SKK’da anlamlı incelme görülürken (P=0.001), 3. aydan itibaren SKK’ da kalınlaşma başladı ve postoperatif 12.ayda işlem öncesi değerlere yaklaştı. Hiçbir olguda ameliyat sırasında ve sonrasında, görmeyi tehdit eden önemli bir komplikasyonla karşılaşılmadı.

Sonuç: Keratokonusta CXL tedavisi topikal anestezi ile uygulanan, görme kaybına veya endotel hasarına neden olmayan güvenilir bir cerrahi yöntem olarak görünmektedir. Görme keskinliğinde hafif bir miktar artış elde edilirken,1 yıllık takipte keratokonus progresyonunu durdurduğu saptanmıştır.

Anahtar Kelimeler

• Crosslinking,Ektazi,Keratokonus,Kornea,Riboflavin

Kaynakça

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