1 / 12

Ahmed El-Massry, M.D.

long-Term Results of Corneal Biomechanical Changes After Refractive Laser Procedures. Ahmed El-Massry, M.D. Professor of Ophthalmology - Faculty of Medicine University of Alexandria Egypt. Nader Bayomi M.D. Sherif Tolees M.D. ASCRS 2010.

ipo
Download Presentation

Ahmed El-Massry, M.D.

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. long-Term Results of Corneal Biomechanical Changes After Refractive Laser Procedures Ahmed El-Massry, M.D. Professor of Ophthalmology - Faculty of MedicineUniversity of AlexandriaEgypt Nader Bayomi M.D. Sherif Tolees M.D. ASCRS 2010 The authors have no Financial interest in the subject matter of this poster

  2. Corneal Hysteisis (CH) is a phenomenon results from the dynamic nature of the air pulse & viscous damping inherited in the cornea. Corneal resistance factor (CRF) is a measurement of the cumulative effects of both the viscous and elastic resistance encountered by the air jet while deforming the corneal surface.

  3. Objective of the study To evaluate the corneal biomechanical changes(Corneal Hysterisis “CH” and Corneal resistance factor “CRF”) after more than one year of corneal Laser refractive surgeries.

  4. Study design Ocular response analyzer was used to measure Corneal hysterisis (CH), Corneal resistance factor (CRF), Goldmann- correlated Intraocular pressure (IOPg) and corneal compensated IOP (IOPc) before and after three months, and one year of different thickness flap created in laser correction procedures.

  5. Study design (cont.) All eyes were subjected to laser ablation and weredivided into 3 groups: Group 1 (50 eyes)Lasik was done using the M2 micro-keratome creating a flap thickness of 130 micron.Group 2 (50 eyes)Epilasik was done using the MoriaEpi-k microkeratome that separates the epithelial sheet in one mass from the Bowman’s membrane.Group 3 (50 eyes)Lasik was done using the 100 microns flap thickness using the OUP-SBK microkeratome of Moria.

  6. Patients and Methods All eyes were subjected to the usual screening investigations andORA: -Preoperatively. - One week postoperatively. - One month postoperatively. - Three months postoperatively. - And one year after the laser refractive procedures. ahmad.elmassary@gmail.com

  7. CH_1Y Results Preop. CH, and postop. 1 week, 1 month, 3 months and 1 year CH in the studied groups.

  8. CRF_1Y Results Preop. CRF, and postop. 1 week, 1 month, 3 months and 1 year CRF in the studied groups.

  9. Results Corneal Hysterisis decreased after 3 monthsone year In Group 1: (Lasik 130 micron flap) 35% 35% In Group 2: (Epilasik) 18% 18% In Group 3: (Thin Flap lasik) 23% 23%

  10. Conclusion • Corneal biomechanical changes decrease after all refractive surgery procedures by three months and remain stable till after one year.

  11. Conclusion • Both Epi-lasik with discarding the flap, and Lasik using OUP-SBK micro-keratome (100micron thickness) are more safe techniques for CH and CRF, after more than one year with statistically significant stable Corneal biomechanical properties in comparison to 130 micron flap lasik.

  12. Conclusion • Epilasik is a perfect surface ablation procedure that also keeps the CH and CRF postoperatively by three months and one year (18%), better than thin flap Lasik (23%), which is also better than 130 micron flap Lasik (35%). • The corneal resistance factor parameter may be more useful than CH parameter in assessing biomechanical changes resulting from lasik.

More Related