Corneal Collagen Cross-Linking Treatment (Cxl) in Keratoconus

Abstract

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.

Keywords

• Crosslinking,Ectasia,Keratoconus,Cornea,Riboflavin

Keratokonusta Korneal Kollajen Çapraz Bağlanma Tedavisi (Cxl)

Abstract

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.

Keywords

• Crosslinking,Ektazi,Keratokonus,Kornea,Riboflavin

References

1. 1. Ruyter I. Composites--characterization of composite filling materials: reactor response. Adv Dent Res 1988, 2(1):122-133.
2. 2. Golomb G, Schoen FJ, Smith MS, et al. The role of glutaraldehyde-induced cross-links in calcification of bovine pericardium used in cardiac valve bioprostheses. Am J Pathol 1987, 127(1):122.
3. 3.Wollensak G, Spoerl E, Seiler T. Riboflavin/ultraviolet-a-induced collagen crosslinking for the treatment of keratoconus.Am J Ophthalmol 2003;135(5):620-7.
4. 4. Kamburoglu G, Ertan A. Intacs implantation with sequential collagen cross-linking treatment in postoperative LASIK ectasia. J Refract Surg 2008;24(7):726-9.
5. 5. Ghanem RC, Santhiago MR, Berti TB, et al. Collagen crosslinking with riboflavin and ultraviolet-A in eyes with pseudophakic bullous keratopathy. J Cataract Refract Surg 2010;36(2):273-6.
6. 6. Hafezi F, Dejica P, Majo F. Modified corneal collagen crosslinking reduces corneal oedema and diurnal visual fluctuations in Fuchs dystrophy. Br J Ophthalmol 2010;94(5):660-1.
7. 7. Khan YA, et al. Riboflavin and ultraviolet light a therapy as an adjuvant treatment for medically refractive Acanthamoeba keratitis: report of 3 cases. Ophthalmology 2011;118(2):324-31.
8. 8. Makdoumi K, et al. UVA-riboflavin photochemical therapy of bacterial keratitis: a pilot study. Graefes Arch Clin Exp Ophthalmol 2012;250(1):95-102.

9. 9. Raiskup-Wolf F, Hoyer A, Spoerl E, et al. Collagen crosslinking with riboflavin and ultraviolet-A light in keratoconus: long-term results. J Cataract Refract Surg 2008;34(5):796-801.
10. 10. Caporossi A, Mazzotta C, Baiocchi S, et al. Long-term results of riboflavin ultraviolet a corneal collagen cross-linking for keratoconus in Italy: the Siena eye cross study. Am J Ophthalmol 2010;149(4):585-93.
11. 11. Hersh PS, Greenstein SA, Fry KL. Corneal collagen crosslinking for keratoconus and corneal ectasia: One-year results. J Cataract Refract Surg 2011;37(1):149- 60.
12. 12. Vinciguerra P, Albè E, Trazza S, et al. Refractive, topographic, tomographic, and aberrometric analysis of keratoconic eyes undergoing corneal cross- linking. Ophthalmology 2009;116(3):369-78.
13. 13. Grewal DS, Brar GS, Jain R, et al. Corneal collagen crosslinking using riboflavin and ultraviolet-A light for keratoconus: one-year analysis using Scheimpflug imaging. J Cataract Refract Surg 2009;35(3):425-32.
14. 14. Koller T, Iseli HP, Hafezi F, et al. Scheimpflug imaging of corneas after collagen cross-linking. Cornea 2009;28(5):510-5.
15. 15. Greenstein SA, Fry KL, Hersh PS. Corneal topography indices after corneal collagen crosslinking for keratoconus and corneal ectasia: one-year results. J Cataract Refract Surg 2011;37(7):1282-90.
16. 16. Goldich Y, Marcovich AL, Barkana Y, et al. Clinical and Corneal Biomechanical Changes After Collagen Cross-Linking With Riboflavin and UV Irradiation in Patients With Progressive Keratoconus: Results After 2 Years of Follow-up. Cornea 2012;31(6):609-14.
17. 17. Spörl E, Terai N, Haustein M, [Biomechanical condition of the cornea as a new indicator for pathological and structural changes]. Ophthalmologe 2009;106(6):512- 20.
18. 18. Wittig-Silva C, et al. A randomized controlled trial of corneal collagen crosslinking in progressive keratoconus: preliminary results. J Refract Surg 2008;24(7):720-5.
19. 19. Coskunseven E, Jankov MR 2nd, Hafezi F. Contralateral eye study of corneal collagen cross-linking with riboflavin and UVA irradiation in patients with keratoconus. J Refract Surg 2009;25(4):371-6.
20. 20. Derakhshan A, Shandiz JH, Ahadi M, et al. Short-term Outcomes of Collagen Crosslinking for Early Keratoconus. J Ophthalmic Vis Res 2011;6(3):155-9.
21. 21. Hersh PS, Greenstein SA, Fry KL. Corneal collagen crosslinking for keratoconus and corneal ectasia: One-year results. J Cataract Refract Surg 2011;37(1):149- 60.
22. 22. Asri D, Touboul D, Fournié P, et al. Corneal collagen crosslinking in progressive keratoconus: multicenter results from the French National Reference Center for Keratoconus. J Cataract Refract Surg 2011;37(2):2137-43