1. Pachymetric changes during corneal collagen cross-linking and effect of hydroxipropylmethylcellulose on corneal thickness Faik Oruçoğlu (Orucov) Kudret Eye Hospital / Istanbul

2. Purpose To evaluate central corneal pachymetric changes during corneal collagen cross-linking (CXL) and effect of hydroxipropylmethylcellulose (HPMC) drops.

3. Hydroxipropylmethylcellulose Hypromellose Hydrophylic pH: 7,2-7,9 Osmolarity 240-300 mOsm

5. Spoerl E,.Safety of UVA-riboflavin cross-linking of the cornea. Cornea 2007;26:385–9 Ophthalmology 2009; 116(12) 2336-9 116(12

6. Methods Grup 1. (N=18). Epithelial abrasion (9mm) 0.1 % Riboflavin drops in dextrane every 3 minutes for 30 minutes. UVA 3mw/cm2 at 365nm for 30 min Grup 2. (N=21). Epithelial abrasion (9mm) 0.1 % Riboflavin drops in dextrane every 3 minutes and hydroxipropylmethylcellulose (HPMC) every 5 minutes for 30 minutes. UVA 3mw/cm2 at 365nm for 30 min Two groups were formed in patients with keratoconus undergoing cross- linking ;

7. Central corneal thicknesses were measured by ultrasound pachimetry – before epithelial abrasion, – after epithelial abrasion and – 30 minutes after beginning riboflavin installation

8. Before epithelial abrasionAfter epithelial abrasionP Grup 1457.2 + 62.6395±54,9<0,001 Grup 2449.7 + 62.6389,4±44,2 0,009 After epithelial abrasion30 minutes after riboflavin installation P Grup 1395±54,9360±44,4<0,001 Grup 2389,4±44,2374,4±38,10,08 450 440 430 420 410 400 390 380 370 360 Group 1 Group 2 After epithelial abrasion 30 minutes after riboflavin

9. Conclusion Decrease of corneal thickness continues with epithelial peeling. This decrease in corneal thickness is significantly reduced by continuing the procedure with the addition of HPMC. Rb+Dextran H2O Rb+Dextran H2O HPMC

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