This presentation try to answer the recent debatable question about which is better LASIK or PRK , when to choose each of them and how to exclude complications of both procedures.

1. Dr. Amr Mounir.MD
Lecturer of Ophthalmology
Sohag University Hospital
By

3. First: Why doctors return to PRK again ?

4. Second: Is LASIK a hazardous technique ?

5. Third: What are benefits of PRK over LASIK ?

6. First: Why doctors return to PRK again ?
Easy technique
No flap related complications
Less ectasia
Less cost

7. Second: Is LASIK a hazardous technique ?
Hazardous in the following conditions
1. Long-term safety
2. Flap related complications
3. Suction high pressure effect on posterior
segment

8. Third: What are the benefits of PRK over LASIK?
 More safe → No flap → No damaging effect in
corneal architecture → Maintained corneal
stability → Less ectasia
Less thinning → More residual bed
 Can be done for suspicious corneas
No effect on posterior segment
No dry eye

9. Economic Aspect
No Blade

10. However, after answering the
previous questions
The last question is:
• Why great evolution had occurred from PRK
to LASIK in the beginning of excimer laser
corneal refractive surgeries

11. PRK is not a completely safe technique, it has
its own problems.

12. Problems of PRK
1. Haze:
• Early: Due to early removal of therapeutic
contact lens (bad healing)
• Late: Subepithelial fibroblasts proliferation:
• UVA exposure
• High correction

13. PRK haze

14. Problems of PRK
2. Epithelial healing problems:
• Persistent defect
• Infection
3. Regression in refraction
4. Slow rehabilitation
5. Scar formation

15. POST.PRK infection

16. Post.PRK Scar

17. Benefits of LASIK
1. Time honored procedure
2. Stable refraction
3. Rapid rehabilitation
4. No haze
5. No epithelial healing problems

18. How can we increase LASIK safety ?
By creating ultrathin flaps by:
1. Sub bowman’s keratomileusis (SBK)
2. Femtocreated flaps

19. Indications of PRK
• Thin cornea
• Suspicious cornea
• In combination with corneal collagen CXL
in keratoconic eyes (Athens protocol)

20. Advanced Surface Ablation
Cataract & Refractive Surgery Today EUROPE May 2013

21. Advanced Surface Ablation
1. LASEK, in which the epithelium is
removed with alcohol
2. Epi-LASIK, in which the epithelium is
mechanically lifted without adjunctive
agents.
In both procedures, laser photoablation is
performed just above the Bowman layer

22. Advantages
1. Done in high myopes (–6.00 to –10.00 D).
2. Avoids all the flap-related complications
seen in LASIK, including incomplete flaps,
free caps, buttonhole flaps, flap striae,
dislocated flaps, flap melts, epithelial
ingrowth, and DLK.
3. Safety in posterior segment.

23. Improvement of PRK quality of vision

24. How to avoid haze in advanced
ablation ?
1. Preoperative :
Ask thoroughly about healing of wounds in
body as general ( over healing e.g: skin
Keloids).

25. How to avoid haze in advanced
ablation ?
2. Intraoperative :
- Mitomycin C application (0.02%).
- Washing the bed with cold BSS every
3 Ds to lessen the thermal effect of laser
ablation

26. How to avoid haze in advanced
ablation ?
3. Postoperative :
- Avoid early removal of contact lens
before complete epithelial healing.(early
onset haze)
- Long term topical steroids therapy .(late
onset haze)
- Avoid sunrays exposure.( Late onset haze)

28. PRK is a good alternative to LASIK as
regard safety and corneal stability,
however it carries some problems
especially haze and epithelial healing
problems.
LASIK is better in straight forward
cases especially with ultrathin flaps.