Steve Schallhorn MD Myth Busters in Patient Selection for LASIK Steve Schallhorn MD

DISCLOSURES Consultant to AMO Global Medical Director Optical Express Consultant to AMO Global Medical Director Optical Express

Thin Cornea “Patients with a central corneal thickness less than 500 microns should not undergo LASIK because they are much more likely to be abnormal and develop ectasia”

Distribution of Preop Central Corneal Thickness thinnest of 3 ultrasonic pachymetry readings Mean:549µ Stdev: 31µ 2 STD below:488µ 81,715 consecutive LASIK – 1 Apr 08 to 31 Mar 09 – IL and mech flaps – 2,181 eyes CCT < 500u – 79,534 eyes CCT >=500u 81,715 consecutive LASIK – 1 Apr 08 to 31 Mar 09 – IL and mech flaps – 2,181 eyes CCT < 500u – 79,534 eyes CCT >=500u

Age Distribution

Preop Sphere

Ectasia has been observed in 3 Patients Pt 1Pt 2Pt 3 Age Preop MRx (R/L) -1.25/-1.0 X /-0.50 X /-1.0 X /-0.50 X / /-0.50 X 095 CCT537 / / / 527 Flap methodMoriaIntralaseMoria Est RSB334 / / / 281 Preop K Ectasia diagnosis Right eye 11 months postop Right eye 18 months postop Left eye 15 months postop TreatmentCXL

Preoperative Sphere “Patients with more than 3D of hyperopia should not undergo LASIK because they are much more likely to be unhappy afterwards”

Dissatisfaction as a Function of Treated Hyperopia Average preop sphere: +2.0 ± 0.9D

Preoperative Astigmatism “Patients with high cylinder should not undergo LASIK because they are much more likely to be unhappy afterwards”

Dissatisfaction as a Function of Treated Astigmatism Average preop cyl: 0.76D Patients

Low Light Pupil Diameter “Patients with >=8mm pupils should not undergo LASIK because they are much more likely to be unhappy and have visual symptoms”

1M LASIK Dissatisfaction vs Low Light Pupil Patients

1M LASIK Problems with Daily Activities and Night Driving vs Low Light Pupil Patients

Hyperopic Presbyopes “A +2.50D 60 year old should not undergo LASIK. An RLE procedure will result in much higher patient satisfaction and less dry eye”

12 Month Age Stratified Random Sample RLELASIK 112 pts159 pts Gender: M/F(%)41% / 59%43% / 57% Age (years): Mean (SD)60.2 ± ± 4.8) Min, Max45 to 7050 to 70 Preop Sphere: Mean (SD)+2.55 ± 0.99D+2.24 ± 0.69D Min, Max+1.00 to Preop Cylinder: Mean (SD)-0.60 ± 0.47D-0.54 ± 0.43D Min, Max0.0 to Preop MSE: Mean (SD)+2.25 ± 0.97D+1.97 ± 0.66D Min, Max0.00 to to +4.25

Procedure vs. Satisfaction P =

“During the past week, how many times a day do you use artificial tears?”

Refractive Target “It is best to target a little myopia in presbyopic patients to enhance their satisfaction”

Mean 1 M Satisfaction vs Postop Sphere Dominant eye in patients >=40 yrs & patients <=30 yrs 1,643 1,173 2,576 7,338 2,439 8,214 1, , More Satisfied

Conclusions Analysis of large patient datasets can provide a unique insight to improve refractive surgery Analysis of large patient datasets can provide a unique insight to improve refractive surgery Patient selection Patient selection Refractive target Refractive target “Myth busters” “Myth busters” Analysis of large patient datasets can provide a unique insight to improve refractive surgery Analysis of large patient datasets can provide a unique insight to improve refractive surgery Patient selection Patient selection Refractive target Refractive target “Myth busters” “Myth busters”