Comparative Studies on Femto-LASIK

Transcription

1 Comparative Studies on Femto-LASIK Assoc Prof Jod Mehta P Royalty: Network Medical Products D Research Funds: Carl Zeiss Meditec Assoc Prof Jod S Mehta BSc.(Hons), MBBS, FRCOphth, FRCS (Ed) Consultant Corneal and External Eye Disease and Refractive Service, Singapore National Eye Centre, Clinician Scientist, Singapore Eye Research Institute, (SERI) Head, Tissue Engineering and Stem Cells Group, SERI Assoc Prof, Duke-NUS Graduate Medical School, Assoc Prof, Dept of Ophthalmology, Yong Loo Lin School of Medicine, NUS Femtosecond Laser + VisuMax Femtosecond Laser, Carl Zeiss Meditec Excimer Laser 1

2 VISUMAX: Spiral-in Pattern INTRALASE: Raster Pattern Visumax Intralase Docking Non-applanating Applanating Suction Corneal Scleral Corneal Interface Curved Flat Pulse Duration fs fs Repetition Rate 500 khz 150 khz Laser Pulse Energy (max) nj 5.0 uj Cutting Pattern Spiral Raster Spot Size 1.0 um <3.0 um Treatment Time 17-18s <20s VISUMAX INTRALASE VISUMAX Curved Patient Interface Treatment pack Lower pressure system Suction ring / applanation cone Higher pressure system 35 to 45 mmhg INTRALASE Flat Patient Interface 2

3 Prospective, randomized, contralateral eye study Bilateral simultaneous LASIK LASIK flap creation One eye: VisuMax 500kHz femtosecond system Fellow eye: 60kHz femtosecond system Randomized: Laterality of the eye to the platform and the platform used for the first eye Excimer laser ablation Wavelight ALLEGRETTO 400Hz in both eyes Spherical equivalent difference of <2.0DS 3 experienced LASIK surgeons (with VisuMax and ) Patients and surgeons interviewed peri-operatively with a standardized questionnaire about their intraoperative experiences and preferences Prospective, randomized, eye study 86 Eyes LASIK flap creation One eye: VisuMax 500kHz femtosecond system Fellow eye: 60kHz femtosecond system Excimer laser ablation Spherical equivalent difference of <2.0DS 3 experienced LASIK surgeons (with VisuMax and ) Patients and surgeons interviewed peri-operatively with a standardized questionnaire about their intraoperative experiences and preferences Visumax Intralase Flap size 7.9 mm 9.0 mm Flap thickness /microns Sidecut angle /degrees Hinge angle /degrees Air pocket NA present Inclusion Criteria meets the standard SNEC LASIK inclusion criteria for LASIK at least 21 years of age and less than 40 years of age. Exclusion Criteria the standard SNEC LASIK exclusion criteria. patients who have opted for monovision Anisometropia of > 3D (Spherical Eq) 3

4 INTRALASE FLAP LE VISUMAX FLAP RE Efficacy 90 Total number of patients- 46 Females 22 (57.9%) Mean age- 29 +/- 5 (range 22 to 39 years) Pre-Op Visumax Month 1 Visumax Month 3 Visumax Pre-op Intralase Month 1 Intralase Month 3 Intralase /4.5 6/6 6/7.5 6/9 6/12 6/18 6/24 6/30 6/45 6/60 CF 3 Months Post Op Visumax Intralase % eyes with UCVA of 6/12 or better 100% 100% % eyes with UCVA of 6/6 or better 81.5% 77.8% % eyes with UCVA of 6/4.5 or better 14.8% 11.1% 4

5 p>0.05 p>0.05 Visumax Intralase % of eyes within +/- 1.0D of attempted correction 92.6% 100% % of eyes within +/- 0.5D of attempted correction 85.2% 85.2% p>0.05 p>0.05 5

6 No major intraop or post-op complications was observed with either machines Subconjunctival haemorrhage was observed in 27 (out of 38) eyes which underwent Intralase VisuMax During vacuum suction VisuMax 0 (0%) 17 (44.7%) Vacuum suction / applanation Femtosecond pass p=0.130 During the femtosecond pass 0 (0%) 22 (57.9%) 4 hours after the procedure = No discomfort 10= Worst pain imaginable p=

7 VisuMax Vacuum suction / Applanation VisuMax 29 (76.3%) 9 (23.7%) Femtosecond pass p= = No fear 10= Maximum fear imaginable Difficulty with docking 3 cases (7.9%) Suction loss 2 cases VisuMax (5.3%) Significant OBL 3 cases VisuMax 1 case (p=0.77) (p=0.152) (p=0.304) 7

8 Easier / smoother flap lift 19 (50.0%) VisuMax 4 (10.5%) No preference 15 (39.5%) 26 (68.4%) VisuMax 1 (2.6%) () Small numbers Surgeons not masked Nursing staff / doctors conducting the questionnaire not masked Loss of light perception occurred frequently with during flap creation. Patients retained light perception throughout the VisuMax flap creating process More patients were fearful of the experience and preferred the VisuMax platform with lower pain scores Surgeons encountered smoother / easier flap lifts with More frequent subconjunctival hemorrhage occurred with 8

9 Femtosecond LASIK with either the Intralase or Visumax FS laser platforms has similar efficacy, safety and refractive outcomes for myopic eyes. Singapore National Eye Centre A Presentation by the Singapore National Eye Centre Tissue Engineering and Stem Cell Team SERI SNEC Prof D Tan Dr M Ang Dr G Tan Dr A Anshu Dr H Kiat SERI Prof R Beuerman Dr XW Tan Dr S Chaurasia Dr G Peh Dr P Paul Rebecca Poh Champa Ravi Promoda Rachael Peh Ryan Fu Dr Federico Dr You Chan 9