1. Topography-Guided Photorefractive Keratectomy (TG-PRK) for Keratoconus (KC) with Simultaneous Collagen Cross-linking (CXL) Using High-Resolution Excimer Laser
Simon Holland
David TC Lin
ASCRS, Chicago, Illinois 2012
*no financial interests*
Purpose
To evaluate efficacy and safety of simultaneous TG-PRK with CXL using high-resolution excimer laser, iVIS

2. Methods
43 eyes keratoconus eyes underwent treatment with high resolution excimer laser
Trans-epithelial TG-PRK with iVIS using the CIPTA program with simultaneous CXL (Dresden protocol)
Maximum refractive error corrected with minimal residual stromal depth 300microns
Data evaluated: pre-operative, 1, 2, 3 and 6 months:
- uncorrected visual acuity (UVA), best corrected visual acuity (BCVA), topography, manifest refraction (MR), symptom score, topography
and keratometry

3. iVIS TG-PRK with CXL for KC
Pre-op 3 Months Post-op UCVA:CF UCVA: 20/80 MR: x080 MR: x150 20/30+ Aim: –1.50
Ginter, Aileen 3

5. iVIS TG-PRK with CXL for KC
Pre-operative months post-op
UCVA: CF UCVA: 20/50-
MR: X110 20/60+ MR: x180 20/40-
Shi, Yan Bin OS 5

6. Shi, Yan Bin

7. Results 43 eyes completed 6 months follow-up
18 (42%) had ≥20/40 or better uncorrected visual acuity (UVA)
36 (84%) had ≥20/40 or better best corrected visual acuity (BCVA)
16 (37%) had BCVA improved, 4 (9%) improved BCVA 2 lines or more, 15 (35%) no change, 2 (5%) lost 2 lines or more
Mean astigmatism decreased -2.67D pre-op to
-1.50D
3 had delayed epithelial healing beyond 5 days with no residual effects and no other complications
Symptom scores at 3 months, n=20, improved in 11, no change in 5 and worse in 4
Dr.Holland, please verify the words in RED. Please make correction and put OK at end of each. Thanks! 7

8. Conclusions
Early results of simultaneous TG-PRK with CXL with the high-resolution excimer laser, iVIS, shows potential to improve both UCVA and BSCVA in CL intolerant KC patients with good efficacy and safety
Advantages include central corneal regularization possible with the iVIS CIPTA program but may be offset by smaller treatment zones and less
reduction in symptoms 8