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  • I acknowledge a financial interest in the Artemis technology - VHF digital ultrasound scanning developed by my colleagues and I at Cornell and licensed to ArcScan Inc
  • The ideal solution would be to increase the depth of field so that both eyes could see clearly at both distance and near.
  • This example shows, a -1.50 defocus with a 7mm pupil, if we add spherical aberration, we actually get more edge detection. If we reduce the pupil size, which of course occurs even in a presbyopic patient when they look at near, you get an increase in depth of field as well. If you combine both of these things, you get a pretty clear image and once you add neural processing, this becomes a clear image.
  • The ideal solution would be to increase the depth of field so that both eyes could see clearly at both distance and near.
  • So far, the non-linear aspheric profiles have been able to increase the depth of field, but not enough to give the patient clear vision at all distances.
  • So, in order to give the patient good reading vision, the non-dominant eye is shifted towards myopia. This results in one eye being clearly focused for distance vision, but only slightly blurred at near, and the other eye being clearly focused for near vision, but only slightly blurred at distance. However, the increased depth of field in each eye means that there is a region where the range of clear vision overlaps – know as a blend zone. The result is that good binocular near and distance vision can be achieved with a lower degree of anisometropia than traditional monovision – which we refer to as micro-monovision. Therefore, much less suppression is required and there is no dissociation between the eyes.
  • In traditional monovision, the depth of field in each eye is comparatively smaller, meaning that the near eye needs to be more myopic for the patient to read comfortably, leaving a gap between the range of vision of the two eyes and replaces the “blend zone” with a “blur zone”.
  • In traditional monovision, the depth of field in each eye is comparatively smaller, meaning that the near eye needs to be more myopic for the patient to read comfortably, leaving a gap between the range of vision of the two eyes and replaces the “blend zone” with a “blur zone”.
  • Therefore, binocular vision is more tolerable than multi-focal corneas as the eye is not programmed to process multiple images
  • Multifocal (and accommodative) intra-ocular lenses have also been designed and are being used
  • In my study using the MEL80, we compared the results of wavefront-guided treatments in a group of highly aberrated eyes with night vision disturbances against a control group of post refractive surgery eyes that were matched for preop myopia, but had been treated with a more modern aspheric ablation profile and were free of night vision problems.
  • In the control group, the spherical aberration was increased post-op, but the normalized contrast sensitivity was unchanged The repair group started with much higher levels of spherical aberration and significantly reduced contrast sensitivity. The wavefont-guided repair reduced spherical aberration enough to improve contrast sensitivity to normal levels….
  • … the fact that there was only a 27% reduction in the total spherical aberration. Assuming that the target would have been the level of spherical aberration in the control group, the wavefront-guided treatment achieved about a 50% reduction toward this level. Nevertheless, normalized contrast sensitivity returned to normal, implying that neural processing was doing the rest of the work for us. This study suggested that the threshold level for night vision disturbances to crop up was around 0.56 microns (analysed in a 6mm zone).
  • So, let me address these points. This is the inside scoop on the induction of spherical aberration. Take a -10 patient and put in this straight-forward so-called Munnerlyn profile - we induce a lot spherical aberration. If we take a -10 and do the Munnerlyn profile, but also put in the inverse of the spherical aberration that we would have induced, we found that we only get a 27% reduction in the induction of spherical aberration. A -10, therefore, needs the inverse spherical aberration profile to be boosted to get more effect. However, when you do this, A. You take much more tissue and B. you start to get deja vue on central islands – this is a wavelight laser case. So, it’s not actually a workable solution. Our latest concept is to go to the crux of the matter and take more peripheral tissue directly. By doing this, we’ve found that we can induce far less spherical aberration in the eye without inducing central islands while achieving large effective optical zones.
  • Finally, the centration issue. If a patient has no angle kappa and we’re refracting them in the phoroptor, then the visual axis and entrance pupil are both aligned with the phoropter lens. But, if there is an angle kappa, we do not then move the lens away from the corneal vetex to align the lens we are refracting with the entrance pupil, the eye presents it’s vertex to the world, not it’s entrance pupil. So, it’s baffling that most companies are still telling surgeons to centre their treatments on the entrance pupil – which creates a new vertex for the cornea, rather than maintaining the one that God provided! So, ablations need to be centred on the corneal vertex which best approximates the visual axis thank-you Milind.
  • Getting N6 from just -0.75 cyl in a 60 year old patient
  • Before we look at some examples, we need to set out the expected vision for a particular refraction
  • Before we look at some examples, we need to set out the expected vision for a particular refraction
  • Before we look at some examples, we need to set out the expected vision for a particular refraction
  • Before we look at some examples, we need to set out the expected vision for a particular refraction
  • And, the outcomes speak for themselves. These 3D graphs show simultaneous 20/20 and newsprint vision - these are surprisingly good results!
  • And I assure you that we didn’t use this method of achieving great results!

Laser Blended Vision for Presbyopia: Laser Blended Vision for Presbyopia: Presentation Transcript

  • Laser Blended Vision for Presbyopia: An Eight-in-one procedure Dan Z Reinstein MD MA(Cantab) FRCSC FRCOphth 1,2,3,4 1. London Vision Clinic, London, UK 2. St. Thomas’ Hospital - Kings College, London, UK 3. Weill Medical College of Cornell University, New York, USA 4. Centre Hospitalier National d’Ophtalmologie, (Pr. Laroche), Paris, France This indication for use is not cleared by the FDA for distribution in the United States
  • Financial Disclosure The author (DZ Reinstein) acknowledges a financial interest in Artemis™ VHF digital ultrasound (ArcScan Inc, Morrison, CO) The author (DZ Reinstein) is a consultant for Carl Zeiss Meditec AG (Jena, Germany)
  • Laser Blended Vision: 8-in-1 Mechanism
    • 5. Retinal image processing [edge detection]
    • 6. Neural summation
    • 7. Blur adaptation
    • 8. Neural suppression
    1. Monovision principle 2. Depth of field to reduce anisometropia 3. Spherical aberration control [DOF without decrease quality of vision] 4. Vertex centration of spherical aberration [OSA coma, on-axis symmetry of image blur]
  • Laser Blended Vision: 8-in-1 Mechanism
    • 5. Retinal image processing [edge detection]
    • 6. Neural summation
    • 7. Blur adaptation
    • 8. Neural suppression
    1. Monovision principle 2. Depth of field to reduce anisometropia 3. Spherical aberration control [DOF without decrease quality of vision] 4. Vertex centration of spherical aberration [OSA coma, on-axis symmetry of image blur]
  • Presbyopia: Ideal Solution Near Intermediate Distance Far Distance Right Eye Left Eye
  • Influence of Spherical Aberration on Depth of Field without spherical aberration with spherical aberration Slides courtesy Hartmut Vogelsang, PhD
  • Influence of Spherical Aberration on Depth of Field Slides courtesy Hartmut Vogelsang, PhD 0.00 D -0.50 D -1.00 D -1.50 D -2.00 D without spherical aberration with spherical aberration
  • Influence of Pupil Diameter on Depth of Field Slides courtesy Hartmut Vogelsang, PhD 0.00 D -0.50 D -1.00 D -1.50 D -2.00 D @ 7 mm @ 4 mm
  • Influence of Pupil Diameter & Spherical Aberration on Depth of Field Slides courtesy Hartmut Vogelsang, PhD 0.00 D -0.50 D -1.00 D -1.50 D -2.00 D @ 7 mm with spherical aberration @ 4 mm
  • Non-Linear Aspheric Presbyopic Ablation Profiles
    • New Presbyopic Profile
    • Increases depth of field
    • Based on non-linear changes in asphericity
    Linear Aspheric Non-Linear Aspheric
  • Simulation for -1.50 D defocus -1.50 D @ 7 mm Add spherical aberration Reduce pupil size to 4 mm With spherical aberration and @ 4 mm Central neural processing
  • Laser Blended Vision: 8-in-1 Mechanism
    • 5. Retinal image processing [edge detection]
    • 6. Neural summation
    • 7. Blur adaptation
    • 8. Neural suppression
    1. Monovision principle 2. Depth of field to reduce anisometropia 3. Spherical aberration control [DOF without decrease quality of vision] 4. Vertex centration of spherical aberration [OSA coma, on-axis symmetry of image blur]
  • Presbyopia: Ideal Solution Near Intermediate Distance Far Distance Right Eye Left Eye
  • Current Possible Depth of Field Increase Near Intermediate Distance Far Distance Right Eye Left Eye 1.50 D 1.50 D
  • Laser Blended Vision: 8-in-1 Mechanism
    • 5. Retinal image processing [edge detection]
    • 6. Neural summation
    • 7. Blur adaptation
    • 8. Neural suppression
    1. Monovision principle 2. Depth of field to reduce anisometropia 3. Spherical aberration control [DOF without decrease quality of vision] 4. Vertex centration of spherical aberration [OSA coma, on-axis symmetry of image blur]
  • Laser Blended Vision – Micro-Monovision Near Intermediate Distance Far Distance Dominant Eye Non-Dominant Eye “ Blend Zone” 1.50 D 1.50 D
  • Contact Lens Monovision Near Intermediate Distance Far Distance Dominant Eye Non-Dominant Eye “ Blend Zone” “ Blur Zone” 1.50 D 1.50 D
  • Contact Lens Monovision Near Intermediate Distance Far Distance Dominant Eye Non-Dominant Eye “ Blur Zone” “ In contact lens monovision, there is a need for a third focal length , for example with computer screens at intermediate distances” Evans BJ. Monovision: a review. Ophthalmic Physiol Opt. 2007;27:417-439.
  • Correcting Presbyopia: Contact Lens Monovision Dominant eye: mainly corrected for distance Non-dominant eye: mainly corrected for near Brain merges two images to see near and far without glasses 59-67% Patients Tolerate Evans BJ. Monovision: a review. Ophthalmic Physiol Opt. 2007;27:417-439.
  • Correcting Presbyopia: Laser Blended Vision Brain merges two images to see near and far without glasses Dominant eye: mainly corrected for distance Non-dominant eye: mainly corrected for near ~97% Patients Tolerate Reinstein DZ et al. LASIK for Hyperopic Astigmatism and Presbyopia Using Micro-monovision With the Carl Zeiss Meditec MEL80. JRS. 2009;25(1):87-93
  • Laser Blended Vision: 8-in-1 Mechanism
    • 5. Retinal image processing [edge detection]
    • 6. Neural summation
    • 7. Blur adaptation
    • 8. Neural suppression
    1. Monovision principle 2. Depth of field to reduce anisometropia 3. Spherical aberration control [DOF without decrease quality of vision] 4. Vertex centration of spherical aberration [OSA coma, on-axis symmetry of image blur] Online Feb 2010 Laser Blended Vision: Binocular UDVA > Monocular UDVA (distance eye) Traditional Monovision: Binocular UDVA < Monocular UDVA (distance eye) Evans BJ. Monovision: a review. Ophthalmic Physiol Opt. 2007;27:417-439.
  • Binocular Vision: Neural Summation
  • Laser Blended Vision: 8-in-1 Mechanism
    • 5. Retinal image processing [edge detection]
    • 6. Neural summation
    • 7. Blur adaptation
    • 8. Neural suppression
    1. Monovision principle 2. Depth of field to reduce anisometropia 3. Spherical aberration control [DOF without decrease quality of vision] 4. Vertex centration of spherical aberration [OSA coma, on-axis symmetry of image blur]
  • Blur Adaptation
    • Wore glasses except for VA measurement
    No glasses throughout Wore glasses throughout No change in Rx
  • Laser Blended Vision: 8-in-1 Mechanism
    • 5. Retinal image processing [edge detection]
    • 6. Neural summation
    • 7. Blur adaptation
    • 8. Neural suppression
    1. Monovision principle 2. Depth of field to reduce anisometropia 3. Spherical aberration control [DOF without decrease quality of vision] 4. Vertex centration of spherical aberration [OSA coma, on-axis symmetry of image blur]
  • Ocular Rivalry and Blur Suppression vs Multifocal
    • Neuronal gates instantaneously select the better image, or elements of each, to obtain the best image for the task at hand
    Awareness OD Suppression OS Source: Monovision in name only. William F Maloney. Ocular Surgery News US Edition October 1, 2006 Binocular Mediating Neuron OD OS
  • Problem With Multi-focality ReSTOR ReZoom Anschütz,Dausch,Klein,Joly (Meditec group, 1991) Avalos, Rozakis, Agarwal (PARM-technique, 1998) G.Tamayo (2000) Concentric distance near zones Diffraction design PROBLEM: Two Images Multi-focal Ablation Profiles Multi-focal IOLs Near Far Near Far
  • Laser Blended Vision: 8-in-1 Mechanism
    • 5. Retinal image processing [edge detection]
    • 6. Neural summation
    • 7. Blur adaptation
    • 8. Neural suppression
    1. Monovision principle 2. Depth of field to reduce anisometropia 3. Spherical aberration control [DOF without decrease quality of vision] 4. Vertex centration of spherical aberration [OSA coma, on-axis symmetry of image blur]
  • Wavefront-Guided Treatment of Spherical Aberration
  • How Effective are Wavefront Repair Treatments? Repair Group Complaining NVDs post LASIK Wavefront-Guided Repair Treatment Control Group Not Complaining NVDs post LASIK 16 eyes in study 4:1 matched for sphere & cyl
    • Aberrations Pre-op
    • Aberrations Post-op
    Compare Aberrations
    • Aberrations Pre-repair
    • Aberrations Post-repair
  • Correlation of Contrast with Wavefront
    • Spherical Aberration
    • Contrast Sensitivity
  • Correlation of Contrast with Wavefront
    • Spherical Aberration
    • Contrast Sensitivity
    • 27% Gross Reduction
    • 53% Net Reduction (cf tolerable level)
    • Tolerable level ~0.56 µm @ 6mm
  • Spherical Aberration Control: The inside scoop Only 27% Effect 6mm Zone -9.25D ablation -10 D -10 D -10 D -10 D
  • Laser Blended Vision: 8-in-1 Mechanism
    • 5. Retinal image processing [edge detection]
    • 6. Neural summation
    • 7. Blur adaptation
    • 8. Neural suppression
    1. Monovision principle 2. Depth of field to reduce anisometropia 3. Spherical aberration control [DOF without decrease quality of vision] 4. Vertex centration of spherical aberration [OSA coma, on-axis symmetry of image blur]
  • Centration: Visual Axis vs Entrance Pupil Phoroptor Lens No Angle Kappa Phoroptor Manifest Refraction Excimer Laser Ablation Large Angle Kappa Ablation Profile Phoroptor Lens
  • Laser Blended Vision: 8-in-1 Mechanism
    • 5. Retinal image processing [edge detection]
    • 6. Neural summation
    • 7. Blur adaptation
    • 8. Neural suppression
    1. Monovision principle 2. Depth of field to reduce anisometropia 3. Spherical aberration control [DOF without decrease quality of vision] 4. Vertex centration of spherical aberration [OSA coma, on-axis symmetry of image blur] Outcomes
  • Measurement of Effective Depth of Field Example: Emmetropic Patient
  • Laser BV Emmetropic LASIK – 56 yo Female 56 yo OD OS Binocular Pre Manifest +0.75 -0.75 x 158 +0.50 -0.75 x 170 BSCVA 20/16 20/16 1 Yr Post Op UCVA 20/16 20/32 20/16 & J2 Manifest +0.25 sph -1.00 -0.50 x 20 BSCVA 20/16 20/16
    • Near eye Rx: -1.00 -0.50 x 20
      • SEQ -1.25 D UCVA 20/63
    Expected Distance UCVA 20/20 0.00 20/25 -0.25 20/32 -0.50 20/40 -0.75 20/50 -1.00 20/63 -1.25 20/80 -1.50
  • Expected Distance UCVA
    • Near eye Rx: -1.00 -0.50 x 20
      • SEQ -1.25 D UCVA 20/63
      • Actual UCVA 20/32 -0.50 D
    20/20 0.00 20/25 -0.25 20/32 -0.50 20/40 -0.75 20/50 -1.00 20/63 -1.25 20/80 -1.50
  • Expected Near Addition – 56 yo Female
    • Near eye Rx: -1.00 -0.50 x 20
      • SEQ -1.25 D UCVA 20/63
      • Actual UCVA 20/32 -0.50 D
    Near UCVA: J2 Age Add 50-52 +1.50 D 52-54 +1.75 D 54-56 +2.00 D 56-58 +2.25 D Over 58 +2.50 D
  • Depth of Field – 56 yo Female
    • Near eye Rx: -1.00 -0.50 x 20
      • SEQ -1.25 D UCVA 20/63
      • Actual UCVA 20/32 -0.50 D
    Near UCVA: J2 Depth of field: 1.50 D Age Add 50-52 +1.50 D 52-54 +1.75 D 54-56 +2.00 D 56-58 +2.25 D Over 58 +2.50 D
  • Outcomes of Non-linear Aspheric Presbyopic Micro-monovision LASIK for Myopia, Hyperopia, and Emmetropia Online Feb 2010
  • Blended Vision: Methods Myopia Hyperopia Emmetropia # Patients 136 111 119 SEQ -3.58 ± 1.80 D up to -8.50 D +2.58 ± 1.17 D up to +5.75 D +0.35 ± 0.35 D -0.50 to +0.75 D Cylinder -0.83 ± 0.64 D up to -2.50 D -0.49 ± 0.50 D up to -3.25 D -0.39 ± 0.30 D up to -1.00 D Age median 49 yrs 43 to 63 median 56 yrs 44 to 66 median 54 yrs 43 to 71
  • Routine LASIK Procedure
    • Hansatome 160
    • CRS-Master custom programming
      • Non-linear aspheric ablation profile DOF
    • MEL80 excimer laser
    • Micro-monovision:
      • Dominant: “plano” [plano to -0.75]
      • Non-dominant: “-1.50 D” [-0.75 to -2.25]
    • >90% follow up at 1 year
    • Results presented including enhancements
  • Blended Vision: Efficacy – Distance Eye
  • Blended Vision: Efficacy – Near Eye Better than expected distance vision in the near eye
  • Blended Vision: Efficacy – Binocular Distance
  • Binocular Vision: Neural Summation
  • Blended Vision: Pre BSCVA vs Post UCVA “ SUCCESS!” All Groups: 94% eyes in the box
  • Blended Vision: Efficacy – Near Vision
  • Laser Blended Vision: Results Emmetropic Population (In Press) Online Feb 2010 Myopia 20/20 & J5 98.5% Hyperopia 20/20 & J5 94.5% Emmetropia 20/20 & J5 97.7% 20/20 J5
  • Blended Vision: Accuracy
  • Blended Vision: Safety
  • Emmetropia BV: Contrast Sensitivity * Statistically significant improvement (p<0.05) * * * * * Myopia Hyperopia Emmetropia
  • Achieving Excellent Results
  • Stereo Acuity
  • Stereo Acuity: Patients & Methods
    • 22 myopes, 38 hyperopes, 16 emmetropes
    • Stereo acuity measurements (4-dot test)
      • Pre-op: near-corrected
      • Post-op: near-corrected
      • Post-op: uncorrected
    • Analysis
      • Safety: post-op near corrected – pre-op near corrected
      • Efficacy: post-op uncorrected – pre-op near corrected
    # Patients 76 SEQ -0.40 ± 2.69 D -7.13 to +3.75 D Cylinder -0.73 ± 0.54 D up to -2.25 D Age median 57 yrs 45 to 69
    • 4-5% of patients with excellent pre-op stereo acuity (40-50 sec) lost 1 patch
    • Post-op near-corrected stereo acuity equivalent to pre-op for ≥60 sec
    • No statistically significant difference (p=0.376)
    Stereo Acuity: Safety (near-corrected pre vs near-corrected post)
    • Post-op uncorrected stereo acuity lower than pre-op near-corrected (p<0.001)
    • But, majority of patients maintained functional stereo acuity
      • 68% achieved 100 secs
      • 93% achieved 200 secs
    Stereo Acuity: Efficacy (near-corrected pre vs uncorrected post)
  • Non-linear Aspheric Micro-Monovision: Summary
  • Summary
    • Non-linear aspheric micro-monovision
      • Correction of pure presbyopia (distance normal)
      • Wide range of refractive error: +5.00 to -9.00
      • Simultaneous accurate correction of cylinder
      • Easily enhanced in future if required
      • Centration on visual axis
      • Minimal compromise to contrast sensitivity and night vision disturbances
      • Tolerated by >95% of patients
      • Functional stereo acuity maintained
      • Performed as bilateral simultaneous 10 minute procedure with fast recovery
  • Laser Blended Vision for Presbyopia: An Eight-in-one procedure Dan Z Reinstein MD MA(Cantab) FRCSC 1,2,3,4 1. London Vision Clinic, London, UK 2. St. Thomas’ Hospital - Kings College, London, UK 3. Weill Medical College of Cornell University, New York, USA 4. Centre Hospitalier National d’Ophtalmologie, (Pr. Laroche), Paris, France Thank You This indication for use is not cleared by the FDA for distribution in the United States