1. Comparison of LASIK and Mitomycin-C Assisted LASEK for Correction of Refractive Errors After Cataract Surgery
Dr. Nitin Balakrishnan,
Crystal Vision Laser Centre, Mumbai, India.
Dr. Shilpa Kodkany,
Dr. Kodkany’s Eye Care Centre, Belgaum, India..
No author has any financial or proprietary interest in any materials or methods mentioned

2. PURPOSE
To compare the results of Laser in situ keratomileusis (LASIK) & Mitomycin C assisted, Laser subepithelial keratomileusis (LASEK), to correct residual refractive errors following cataract surgery.
DESIGN
Dual centre, comparative, retrospective study.

3. METHODS Nineteen Patients (20 eyes) - 10 males & 9 females had LASIK.
Nineteen Patients (19 eyes) - 8 males & 11 females had LASEK.
Patient’s Age varied from 51 to 66 years.
Interval between Cataract Surgery and Refractive procedure – 3 to 36 months(mean 14 months).
All Patients had Phakoemulsification with In the Bag IOL implants.
Pre-op Spherical Equivalent Refraction (SEQ) to – 5 Diopters..

4. METHODS Ablated bed treated with 0.02% Mitomycin C for 90 seconds
LASEK performed with 20% alcohol, for Mechanical Epithelial Debridement.
Ablated bed treated with 0.02% Mitomycin C for 90 seconds
LASIK flap made with Moria MII microkeratome, with a thickness of 130 or 90 microns.
Wavelight Allegreto eximer laser was used for all patients.
With repetition rate of 200 Hz & optical zone of 6 or 6.5mm.
Eyes with tracking difficulties were excluded.
Uncorrected Visual Acuity (UCVA),Best Spectacle-corrected Visual Acuity(BSCVA), percentage of eyes within Half diopter (D) of targeted refraction, targeted v/s achieved spherical equivalent correction and gain/ loss in Snellen’s lines were compared between the two groups.
Length of follow up - 6 months

5. RESULTS - UCVA Percentage of eyes with UCVA ≥ 20/20
Postoperative period (months)
Mean UCVA better in the LASIK group from 1 – 4 months
No significant difference in mean UCVA at 6 months

6. RESULTS - BSCVA Percentage of eyes with BSCVA ≥ 20/20
Postoperative period (months)
Mean BSCVA better in the LASIK group from 1 to 3 months
No significant difference in mean BSCVA from 4 to 6 months

7. RESULTS - Post op Spherical Equivalent Refraction - 6 months
Percentage of eyes
Post op Spherical Equivalent Refraction in D

8. RESULTS - Percentage of eyes within ± 0.5D of Targeted Refraction

9. RESULTS - Targeted v/s Achieved Spherical Equivalent Refraction(LASIK) Group
20 eyes
Targeted

10. Targeted v/s Achieved Spherical Equivalent Refraction(LASEK) Group
19 eyes

11. RESULTS - CHANGE IN SNELLEN’S LINES OF BCVA
Percentage of eyes
No eyes lost 2 or more Snellen’s lines of BCVA
6 eyes gained 1 Snellen’s line of BCVA in Both groups
2 eyes gained 2 Snellen’s lines of BCVA in LASIK group v/s 1 eye in LASEK group

12. CONCLUSIONS
Both Mitomycin C assisted LASEK and LASIK effective in correcting post Cataract residual refractive errors.
Short term superiority of LASIK over LASEK in the immediate post-op period.
Equally good refractive correction at 6 months
Gain in Snellen’s lines in BCVA, almost equal in both groups.
Subepithelial Haze in LASEK group significantly less due to Mitomycin C , which decreased from Grade I + in first 2 months to < grade 0.5 at 6 months.
Longer term studies required to determine refractive stability of the two procedures.
REFERENCES
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