ONE THOUSAND WAVEFRONT GIDED TREATMENT ON MICROSCAN VISUM. Mickael Yablokov. I have no any financial interests in any products mentioned in this paper

Transcription

1

2 ONE THOUSAND WAVEFRONT GIDED TREATMENT ON MICROSCAN VISUM Mickael Yablokov I have no any financial interests in any products mentioned in this paper Ophthalmology clinic Eye Surgery, Kostroma, Russia

3 Goal To determine the predictability, efficacy, safety, and stability of wavefront-guided treatments for low to moderate myopia and myopic astigmatism with the Microscan Visum 500 Hz excimer laser platform (Optosystems, Russia) and IRX3 Imagine Eyes aberrometer. The follow-up was 6 months.

4 Wavefront-guided treatments with Microscan Visum 500 Hz excimer laser (Optosystems, Russia) Repetition rate 500Hz Flying small spot 0,9 mm beam Closed-loop eye tracking Response time 3 ms Long term ablation fluctuation <2% Optical zone to 8,0mm Aspherical transition zone to 10mm

5 IRX3 Wavefront aberrometer (Imagine Eyes, Orsay, France) IRX3-Imagine Eyes autorefkeratometer, wavefront aberrometer with high resolution Shack- Hartmann technology Spatial resolution at the eye pupil plane μm Wavefront aberration order range - Zernike order 10

6 PlatoScan Wavefront Guided Treatment Algorithm for MicroScan Visum Patent Application of INPUT: IRX3-Imagine Eyes Zernike wavefront data OUTPUT: calculated personalized operations for MicroScan Visum Direct access to IRX3-Imagine Eyes patient database Flying spot algorithm provides smooth and stable postoperative stromal bed

7 Centration Automatic compensation of the shift between the center of a narrow pupil in the illuminated surgical field and the center of a large pupil at aberrometry

8 MicroScan Visum: treatment window

9 Characteristics of the patients Number of eyes 1021 eyes of 535 patients Age 28 ± 8 (18 to 69 years) Pupil size (mesopic conditions) Optical Zone Treatment (Blended) Zone 5.88 ± 0.64 (4.9 to 8.0 mm) 6.12 ±0.11 (6.0 to 6.5 mm) 8.01 ±0.11 (7.9 to 8.4 mm) Pre operatively (mean) Sph ± 1.84 D (+1.5 to D) Cyl ± 0.84 D ( 0 to D) SEQ ± 1.80 D ( to D) UDVA 0.18 ±0.18 ( 0.01 to 1.0) CDVA 1.10 ±0.15 (0.6 to 1.6)

10 The mean preoperative CDVA was 1.10 ±0.15 (range: 0.6 to 1.6). The mean postoperative UDVA was 1.16 ±0.14 (range: 0.8 to 1.6) A statistically significant improvement was noted in the mean postoperative UDVA compared to the mean preoperative CDVA (t=7.90; P<.005) Uncorrected distance visual acuity was 1,0 or better in 996 (97.5%) eyes and 1.2 or better in 676 (66.2%) eyes. Efficacy 6-month data

11 Predictability 6-month data Wavefront-guided LASIK successfully reduced the average MRSE from Pre Op ±1.80 D ( to D) to Post Op ±0.29 D (-1.0 to D) Postoperative spherical equivalent refraction was within 0.50 D of intended correction in 906 (89%) eyes

12 Cylinder Predictability 6-month data Comparison of attempted vs. achieved cylinder correction The regression line has the equation Y = 1.002*X which shows a slight hyperopic shift (mean 0.11 ± 0.22 D) at 6 m post-op Wavefront-guided LASIK successfully reduced the average cylinder From Pre Op ±0.84D ( 0 to D) to Post Op ±0.16 D ( 0 to D) for all eyes 917 (90%) of the eyes had less than 0.5 D of cylinder

13 The mean preoperative CDVA was 1.10 ±0.15 (range: 0.6 to 1.6) The mean postoperative CDVA was 1.20 ±0.11 (range: 1.0 to 1.6) A statistically significant improvement was noted in the mean postoperative CDVA compared with the mean preoperative CDVA (t=12.52; P<0.005) 404 eyes (39.5%) gained at least 1 line of corrected distance visual acuity (CDVA) 981 eyes (96%) remained unchanged or gained one or more lines of CDVA vision No eyes lost more than 1 line of CDVA Safety 6-month data The improvement of CDVA was statistically significant (p < 0.001) due to the minimal aberration induction

14 Magnitude and orientation of cylinder Double angle minus-cylinder scatter plot for pre- and postoperative manifest cylinder refraction Mean vector cylinder changed from -0.43D at 12 to -0.04D at 200

15 Stability 16-month data The mean preoperative refraction of D decreased to at one month. The overcorrection observed at 1 month indicates no significant regression from to D at 16 month. Mean postoperative SEQ was 0.04 diopters (D) (range: 0.69 to D) at 16 months

16 Complications 1. No laser- related complications were reported 2. Postoperative complications included: flap displacement in one case due to a fingernail injury flap striae in 2 cases due to eye rubbing diffuse lamellar keratitis in 2 cases (two eyes of the same patient). The patient was treated with fortified cortisone drops and did not experience CDVA lines loss at the end of the follow-up

17 Conclusions Wavefront-guided PlatoScan treatments with the Microscan Visum platform for myopia and myopic astigmatism are safe and effective with excellent visual acuity and refractive outcomes. Optimized laser shot delivery map, larger treatment zone, enhanced tracking device, improved alignment, high stability of ablation may be responsible for that. The observed efficacy, predictability, safety and stability parameters comply the FDA requirements for myopic LASIK corrections.