1. University of California, San Diego Shiley Eye CenterM
ini-Enhancement of LASIK
Nicole Brandt, M.D. / Myoung Joon Kim, M.D.
Tracy Purcell, Ph.D. / David J. Schanzlin, M.D.
University of California, San Diego Shiley Eye Center
No author has a financial or proprietary interest in any material or method mentioned.

2. INTRODUCTION LASIK enhancements are generally safe and effective for
the treatment of residual visual complaints such as blurry
vision, decreased night vision and monocular diplopia.*
Most physicians perform enhancements when the refractive
error is greater than 1 D and UCVA ≤ 20/40.
What about the treatment for small residual refractive
errors (Spherical equivalent < ±1 D and UCVA > 20/40)?
Does the risk of enhancement in these patients outweigh
the benefit?
* Retreatment of LASIK, J Refract Surg 2006

3. INTRODUCTION
During our literature search, we were unable to find any studies
that focused on the enhancement of small refractive errors or
Mini-Enhancements.
PURPOSE
We performed a retrospective study on a subset of patients:
1) To characterize patients who underwent Mini-Enhancements
2) To investigate visual outcomes of Mini-Enhancements
3) To evaluate complications of Mini-Enhancements

4. METHODS We performed a retrospective chart review on all LASIK
patients treated by one surgeon (DJS) from January 2007
through December 2007 that required a Mini-Enhancement.
Primary Procedure:
LASIK flap creation with IntraLase
Myopic treatment targeted at plano
Definition of Mini-Enhancement:
Enhancement of a residual refractive error that is
less than 1 D in spherical equivalent.
Laser Platform for Enhancement:
VISX STAR S4 IR (AMO, Santa Ana, CA)

5. RESULTS Patient Demographics: 41 eyes in 29 patients
Patient Age: 43.9±10.1 years
Bilateral Mini-Enhancement: 12 patients (41.4%)
Duration between primary LASIK to enhancement:
8.40±4.62 months (range 2.5 to 8 months)
Enhancement procedure:
Flap lift : PRK = 37 : 4
Standard : Custom = 35 : 6

6. RESULTS Pre-enhancement refractive errors:
SPH -0.62±0.40 D (range to -1.50)
CYL ±0.36 D (range Plano to +1.50)
CYL ≥0.75 D : 13 eyes (31.7%)
CYL ≤0.50 D : 28 eyes (68.3%)
UCVA Pre-enhancement, LogMAR:
0.14±0.13 (LogMAR 0.14 = 20/27.8)
UCVA Post-enhancement, LogMAR, at 1 month:
-0.04±0.09 (LogMAR = 20/18.3)

7. UCVA Pre and Post-Enhancement
RESULTS
UCVA Pre and Post-Enhancement
Number of Eyes

8. RESULTS Post-Enhancement Gain of UCVA within 3 months Number of Eyes
19.5%
80.5%
Number of Eyes
Number of Lines of UCVA gained

9. 82.9 % of eyes achieved UCVA ≥ Pre-enhancement BSCVA
RESULTS
Pre-Enhancement BSCVA vs. Post-Enhancement UCVA
17.1%
82.9%
Number of Eyes
Difference in Lines of Visual Acuity
82.9 % of eyes achieved UCVA ≥ Pre-enhancement BSCVA

10. RESULTS Complications (Cx)
Flap striae: 4 eyes (10.8% of the Flap Lifts)
Postoperative UCVA in eyes with flap striae
20/20 1 eye
20/25 1 eye
20/30 2 eyes
4 eyes

11. CONCLUSION Overall, Mini-Enhancements were quite successful and
showed excellent visual outcomes.
81% of patients gained 1 or more lines of UCVA.
No patients lost UCVA after mini-enhancement.
83% achieved UCVA = pre-enhancement BSCVA
Of the patients who did not achieve pre-enhancement
BSCVA, approximately one-third were due to
flap striae.