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STAR S4 IR Excimer Laser System Physician Certification Course Place for Conference or Author Month Day, 200X 2012.03.13-ST4862
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2 Purpose The purpose of this presentation is to certify physicians to use the STAR S4 IR Excimer Laser System In addition to completing this course, it is the responsibility of physicians to read and understand the STAR S4 IR Excimer Laser System Operator’s Manual WaveScan Operator’s Manual Professional Use Information Patient Information Booklet
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3 Agenda Introduction to the STAR S4 IR Excimer Laser System Introduction to CustomVue Refractive Labeling Pre-Operative Evaluation WaveScan System Review Surgical Planning STAR S4 IR Excimer Laser System Calibration STAR S4 IR Excimer Laser System Hardware Overview Surgical Technique STAR S4 IR Excimer Laser System Conventional Ablations
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Introduction to the STAR S4 IR Excimer Laser System The STAR S4 IR Excimer Laser System is a 193 nm Excimer laser system capable of delivering Conventional (manifest refraction based) Treatments Wavefront Guided Treatments Therapeutic Treatments
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Introduction to the STAR S4 IR Excimer Laser System STAR S4 IR Excimer Laser System Components Top Hat (non Gaussian) 193 nm beam 3 D ActiveTrak eye tracking system For Wavefront Guided Treatments the following features are available Iris Registration (IR) Variable Spot Scanning (VSS) Variable Repetition Rate (VRR)
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6 CCD CameraLenslet Array Outgoing WaveCCD-Image WaveScan System Hartmann-Shack Wavefront Aberrometer Components of the CustomVue Procedure
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CustomVue Procedure The CustomVue procedure is a wavefront guided treatment There are three components to the CustomVue procedure 1.WaveScan WaveFront system to measure the wavefront of the eye 2.WaveScan Software to reconstruct the wavefront and calculate ablation instructions that are transferred to the S4 IR System 3.S4 IR Excimer Laser system that will execute the ablation instruction 7
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8 Components of the CustomVue Procedure WaveScan CustomVue Software: Proprietary VISX smart pulse-packing software Zernike Reconstruction Used for Review Fourier Reconstruction Used for Treatment
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9 STAR S4 IR Excimer Laser System 100% Variable Spot Scanning treatment with automatic centering and Iris Registration Components of the CustomVue Procedure
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10 Advantages of the CustomVue Procedure Optical zone adjustability Variable spot scanning and thermally balanced treatments with better adherence to an individualized target shapes Availability of compensation for cyclorotation and compensation for pupil centroid shift Direct transfer (USB) of patient treatment data to the laser to reduce transposition errors
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11 Higher Order Aberrations and the CustomVue Treatment There is no clinical data to suggest Higher Order pre- operative RMS should be considered when deciding to perform wavefront - guided ablations
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12 Refractive Labeling
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13 Refractive Labeling Physicians should refer to the STAR S4 IR Excimer Laser System Operator’s Manual for a complete discussion of FDA approved Labeling for LASIK and PRK. The following slides review labeling and are not intended to be a complete or comprehensive review.
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14 Refractive Indications The VISX STAR Excimer Laser System with Variable Spot Scanning (VSS ™ ) and the WaveScan WaveFront System is indicated for wavefront-guided laser assisted in situ keratomileusis (LASIK): In patients who are 21 years of age or older With refractive stability
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15 The STAR ™ Excimer Laser System is indicated for Photorefractive Keratectomy (PRK): In patients who are 18 years of age or older for the treatment of spherical myopia up to - 6.00D In patients who are 21 years of age or older for the treatment of myopic astigmatism and hyperopic astigmatism ( see slide 14 for full approved range) With refractive stability Refractive Indications
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CustomVue LASIK Treatment Ranges SphereCylinderSpherical Equivalent Myopic Astigmatism -11.75-3.75-11.75 Hyperopic Astigmatism +3.75+2.75+3.75 Mixed Astigmatism X +0.25 to +5.75 X 16
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Conventional PRK Treatment Ranges SphereCylinderSpherical Equivalent Myopic Astigmatism -12.00D-4.00D-12.00D Hyperopic Astigmatism +5.00D+4.00D+6.00D Mixed Astigmatism NA 17
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Conventional LASIK Treatment Ranges SphereCylinderSpherical Equivalent Myopic Astigmatism -14.00D-5.00D-14.00D Hyperopic Astigmatism +5.00D+3.00D+6.00D Mixed Astigmatism X<6.00DX 18
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19 Refractive Stability Stable manifest refraction as evidenced by less than or equal to the following change in either spherical or cylindrical component of manifest refraction over the previous year is required. Myopia: ±0.50D Hyperopia: ± 1.00D Mixed Astigmatism: ±1.00D High Myopia: ±1.00D
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20 Contraindications Laser refractive surgery based on a CustomVue treatment, Conventional LASIK or Conventional PRK is contraindicated in: Patients with collagen vascular, auto-immune or immunodeficiency diseases Women who are pregnant or nursing Patients with signs of keratoconus or abnormal corneal topography Patients who are taking the following medications: –Isotretinoin (Accutane ® ) –Amiodarone hydrochloride (Cordarone ® ) Accutane is a registered trademark of Hoffman-La Roche, Inc. Cordarone is a registered trademark of Sanofi
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21 Warnings LASIK or PRK is not recommended in patients who have: Diabetes A history of Herpes simplex or Herpes zoster keratitis Significant dry eye that is unresponsive to treatment Severe allergies
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22 ELECTROMAGNETIC FIELD (EMF): The thyratron emits an electromagnetic pulse which is shielded by the metal coverings of the STAR S4 IR Excimer Laser System. This metal covering reduces the EMF below the limits set by applicable standards for electromagnetic compliance. WARNING: The effects of electromagnetic emissions from the excimer laser system on other devices, such as cardiac pacemakers or implanted defibrillators, are unknown. Operation of the laser in proximity to such devices is not recommended. Warnings
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23 Precautions The safety and effectiveness of the STAR S4 IR Excimer Laser System has not been established in: Patients with corneal neovascularization within 1.0 mm of the ablation zone LASIK and PRK patients under the age of 21 years –With the exception of PRK patients who are 18 years of age or older for the treatment of spherical myopia up to - 6.00D
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24 The safety and effectiveness of the STAR S4 IR Excimer Laser System for LASIK correction have not been established in patients with: Progressive myopia, hyperopia or astigmatism Ocular disease, corneal abnormality, previous corneal or intraocular surgery, or trauma in the ablation zone A history of glaucoma Residual corneal thickness < 250 microns at the completion of the ablation The medication Sumatriptan (Imitrex ® ) Imitrex is a registered trademark of GlaxoSmithKline Precautions
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25 To avoid corneal ectasia, the posterior 250 microns of the corneal stroma should not be violated by the laser or the microkeratome Patient pachymetry - (Non-nomogram adjusted depth of treatment + flap thickness) = > 250 microns Precautions
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26 The safety and effectiveness of this laser for wavefront guided LASIK correction have not been established in patients with: WaveScan-measured pupil size < 5.0 mm Precautions
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27 The safety and effectiveness of wavefront- guided LASIK surgery have only been established: In Myopia with an optical zone of 6.0 mm and an ablation zone of 8.0 mm In Hyperopia with an optical zone of 6.0 mm and an ablation zone of 9.0 mm In Mixed Astigmatism with an optical zone of 6.0 mm and an ablation zone of 9.0 mm Precautions
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28 All CustomVue treatments should be performed with humidity between 40-45% and the temperature between 68 - 72° F. The anticipated post-operative keratometry value in any meridian must be >34D to < 50D. Precautions
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29 During the FDA CustomVue clinical trial for highly myopic eyes, an "in the stromal bed" pachymetric measurement was performed to assure a minimum residual stromal bed of 250 microns. Precautions
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30 Patient Information Booklet and Professional Use Information Prospective patients, as soon as they express an interest in laser vision correction and prior to undergoing surgery, must receive from the treatment provider the Patient Information Booklet. Prior to undergoing surgery, prospective patients must be informed of the alternatives for correcting their refractive error including eyeglasses, contact lenses, and other refractive surgeries. All surgeons should read the Professional Use Information prior to performing procedure procedures with the STAR S4 IR Excimer Laser system.
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31 FDA Reporting Requirement Abbott MDR Program Abbott is required by law to report any of the following events (MDR = Medical Device Reporting) Serious Injury or Death Permanent impairment of a body function An injury that necessitates medical or surgical intervention by a health care professional A malfunction occurred that if it were to reoccur may likely cause or contribute to death or serious injury
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32 FDA Reporting Requirements MedWatch Program In addition to the MDR Report Abbott is required to file, users are required to file Form FDA 3500A “MedWatch Mandatory Reporting” For more information, call the DSMA at (800)638-2041
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33 Pre-Operative Evaluation
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34 Pre-operative Examination Baseline evaluation of patients requesting CustomVue or Conventional treatments should be performed within 30 days of laser refractive surgery
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35 Discontinuance of Contact Lenses Soft lenses - discontinue lens wear at least two weeks prior to examination and treatment Hard (PMMA) or RGP lenses - discontinue lens wear at least three weeks prior to examination and treatment with stable topography (keratometry) and refraction 3 topographic maps (central keratometry readings) and MR taken at 1 week intervals. The last two readings must not differ by > 0.5D
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36 Discontinuance of Contact Lenses Contact Lenses cause: –Reversible corneal topographic changes –Alterations in corneal thickness Contact Lenses must be discontinued prior to CustomVue treatments to allow these reversible corneal changes to resolve
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37 Sequence of Pre-Op Exams Wavefront-Guided Treatments WaveScan System Keratometry Corneal Topography WaveScan Guided Manifest Refraction SLE/Tonometry/Pachymetry Cycloplegic Refraction DFE Post-Cycloplegic Refraction If necessary
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38 WaveScan Exams WaveScan exams with 6.0 mm wavefront diameter are preferred for treatments The minimum size of the wavefront diameter must be >5.0 mm to calculate a CustomVue treatment Measurements with a wavefront diameter <5.0 mm will be unavailable for selection
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39 WaveScan Adjusted Manifest Refraction (WAMR) Obtain a WaveScan exam at the beginning of the pre-operative evaluation prior to other measurements Place the WaveScan cylinder measurement (axis and magnitude) in the phoropter or trial frame Refine the sphere to yield the most letters read with the least minus
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40 Pre-operative Examination Uncorrected Visual Acuity Refraction (WAMR) Manifest Refraction –Myopia - resolution based, not contrast based end point of refraction least minus to see most letters –Astigmatism - Jackson Cross Cylinder - maximize magnitude of cylinder –Hyperopia - Pushed Plus technique Best Spectacle Corrected Visual Acuity Do not stop at 20/20
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41 Astigmatism Refractive, keratometric and topographic cylinder occasionally do not match in axis or magnitude Treatment is based on WaveScan and/or Manifest cylinder When disparity occurs, proceed very cautiously and ascertain stability by repeated measurements over time
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42 Cycloplegic Refraction Cycloplegic Refraction (1% cyclopentolate) True cycloplegia reduces accommodation and allows evaluation of: an over-minused myope maximal hyperopia (manifest and latent) Only refine the sphere during the cycloplegic refraction
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43 Comparison Between Sphere and Cylinder Myopia Difference between WaveScan and manifest sphere or cylinder powers must be within +/- 0.50D Difference between manifest and cycloplegic sphere or cylinder powers must be within +/- 0.50D Difference between WaveScan and cycloplegic sphere or cylinder powers must be within +/- 0.50D For eyes with > 0.50D cylinder, the manifest cylinder axis must be within 15° of the WaveScan cylinder axis
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44 Comparison Between Sphere and Cylinder Hyperopia/Mixed Astigmatism Difference between WaveScan and manifest sphere or cylinder powers must be within +/- 0.75D Difference between manifest and cycloplegic sphere or cylinder powers must be within +/- 0.75D Difference between WaveScan and cycloplegic sphere or cylinder powers must be within +/- 0.75D For eyes with > 0.50D cylinder, the manifest cylinder axis must be within 15° of the WaveScan cylinder axis
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45 Keratometry Keratometry is required Manual K’s preferred Auto K’s are acceptable Simulated Topography K’s are sub-optimal K1 = flat K K2 = steep K K2 Axis= axis of steep K
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46 Pre-operative Examination Pupillometry Bright and dim illumination measurement Corneal Topography - necessary in all patients R/O Keratoconus or any other abnormality R/O CL related abnormalities Verify post-operative results
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47 Pre-operative Examination Slit Lamp Exam Tonometry Pachymetry Ultrasonic pachymetry required for LASIK/PRK Dilated Media and Fundus Exam
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48 Residual Posterior Stroma There must be at least 250 microns of stroma remaining following the ablation to prevent iatrogenic keratoectasia The flap does not provide tectonic support to the cornea post LASIK The following calculation must be done prior to treatment Central Corneal Thickness - (Flap Thickness + Ablation Depth) must be > 250 microns
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49 Residual Posterior Stroma The ablation depth should be based on the actual depth of the non-nomogram adjusted myopic desired correction as this is indicative of the amount of tissue that is effectively removed
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50 WaveScan System Review Take WaveScan Measurement Design CustomVue Treatment Perform CustomVue Treatment
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51 Surgical Planning and Surgical Technique
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52 Surgical Planning and Technique “Everything that goes on in and around the laser room is the responsibility of the operating surgeon !!!”
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53 STAR S4 IR Excimer Laser System Nomogram Development
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54 WARNING The following nomogram recommendations serve as a guideline for Conventional and CustomVue procedures with the STAR S4 IR Excimer Laser System
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55 The following nomogram recommendations are made based on adherence to the refraction techniques, treatment dimensions, surgical techniques and environmental conditions discussed in the STAR S4 IR Physician Certification Course WARNING
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56 Nomogram Warning Nomograms developed for other laser systems CANNOT be used with the STAR S4 IR Excimer Laser System. Nomograms for Conventional and CustomVue procedures are different.
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57 Initial CustomVue Nomogram Recommendations
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58 CustomVue Ablation Dimensions The safety and effectiveness of wavefront- guided surgery have only been established In Myopia with an optical zone of 6.0 mm and an ablation zone of 8.0 mm In Hyperopia with an optical zone of 6.0 mm and an ablation zone of 9.0 mm In Mixed Astigmatism with an optical zone of 6.0 mm and an ablation zone of 9.0 mm
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59 CustomVue Ablation Dimensions Procedures performed with different treatment dimensions may yield different (i.e., less predictable) results Enlarging the Optical Zone will result in deeper ablations that take more time to deliver Enlarging the Ablation Zone will result in longer treatments
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60 CustomVue Nomograms Myopia Nomograms for CustomVue myopic LASIK typically involve an increase in the WaveScan sphere relative to the manifest refraction
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61 CustomVue LASIK for Myopia WaveScan Spherical Equivalent < -6.00D Use Physician Adjustment to bring the WaveScan Sphere to the Manifest Sphere Add 0.25D more minus ( Physician Adjustment of -0.25D) in patients younger than 35 years of age
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62 CustomVue LASIK for Myopia WaveScan Spherical Equivalent > - 6.00D Use Physician Adjustment to bring the WaveScan Sphere to the Manifest Sphere
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63 CustomVue LASIK Hyperopia and Mixed Astigmatism Hyperopia and Mixed Astigmatism No adjustment if the WaveScan and Manifest Sphere are within 0.75D
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64 Refining Your CustomVue Nomogram
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65 Refining Your Nomogram It is expected your individual nomogram may differ from our initial recommendations In order to develop an individualized nomogram, a careful retrospective analysis of your refractive results is required This retrospective analysis should be made based on data obtained after the point of refractive stability (see below)
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Refractive Stability Myopic Astigmatism1-3 months Hyperopic Astigmatism3-6 months Mixed Astigmatism3-6 months 66 Patients must be refractively stable prior to modifying your nomogram
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67 Nomogram Development Many factors may influence individual nomograms Temperature Humidity Patient age Patient refractive error Microkeratome Elevation Surgical technique
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68 Adjusting Your Nomogram Start out slowly with nomogram modifications Change one variable at a time
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69 The Use of the Percentage Nomogram Adjustment
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70 CustomVue Percentage Nomogram Adjustment The Percentage Nomogram Adjustment allows the surgeon to make a percentage adjustment to the entire WaveScan-defined ablation (includes that HOA’s) A maximum adjustment of ±10% is allowed The Percentage Nomogram Adjustment is programmed on the Design screen
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71 Percentage Nomogram Adjustment Design screen with detail of Nomogram Field
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72 Percentage Nomogram Adjustment The Percentage Nomogram Adjustment does not change the shape of the ablation A greater or lesser number of pulses are used to achieve the WaveScan-defined target shape (including higher and lower order terms) As a result, the Percentage Nomogram Adjustment does not affect the calculated depth (Maximum Ablation Depth)
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73 Percentage Nomogram Adjustment The Percentage Nomogram Adjustment should be used to compensate for results based on individual differences in environmental conditions and surgical technique after a critical review of refractive results The Percentage Nomogram Adjustment is preferred for nomogram adjustment purposes because it adjusts the entire wavefront treatment (not only the sphere)
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74 Percentage Nomogram Adjustment The Percentage Nomogram Adjustment is different than the Physician Adjustment The Physician Adjustment allows you to adjust the spherical component of the WaveScan refraction by +/- 0.75D The Physician Adjustment can be used as an endpoint adjustment to deviate from emmetropia –e.g., planned post-operative target of -0.25 in a 55 year old patient
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75 Percentage Nomogram Adjustment One method to produce a percent nomogram adjustment which may be used with the following calculation: For each CustomVue patient perform the following calculation post-operatively (Post -Op MRSE )/ (Pre-Op WaveScan equivalent)x100) Calculate the mean percent for all CustomVue patients Please note that the above is intended as an example and does not represent the only valid method for determining a percentage nomogram adjustment
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76 Percentage Nomogram Adjustment Pre-Op WaveScan Equivalent Post-Op MRSE Post Op MR /Pre-WaveScan x 100 Patient 1-5.00-0.25+5.0% Patient 2-4.75+0.25-5.26% Patient 3-5.50-0.50+9.09% Mean %+2.94% For Demonstration Purposes only > 50 eyes are recommended for this analysis
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77 STAR S4 IR Excimer Laser System Calibration
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78 System Calibration Requirements Complete calibration is required each day when the system is powered up Abbott requires that a –4.00 D sphere calibration be tested after every third ocular treatment
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79 Fluence Calibration Fluence calibration adjusts the laser system energy to maintain a constant delivered fluence of 160 mJ/cm2. Fluence calibration is performed: –at system startup –before each patient treatment procedure (with the exception of fellow eyes) –any time the operator selects SET FLUENCE on the Lens Calibration screen
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80 System Calibration Calibration Platform with Calibration Plastic
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81 Lens Calibration Myopic Sphere Myopic Cylinder Flat/Block Flat Hyperopic Sphere Centering
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82 Lens Calibration ActiveTrak ™ System Calibration in conjunction with Beam Centering required The ActiveTrak System Calibration and Beam Centering are accessed on the Lens Calibration screen by selecting “Centering”. The ActiveTrak System aligns the treatment center as defined by the eye tracker in relation to the laser beam. Beam centering, done in conjunction with the ActiveTrak System calibration, aligns the reticle in relation to the laser beam. This test ablation must be done as a part of daily calibration procedure.
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83 Reticle Alignment Check the laser beam/reticle alignment Reticle adjustment knobs
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84 STAR S4 IR Excimer Laser System Hardware Overview
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85 Laser Safety Emergency Stop Button Know where the EMERGENCY STOP button is located
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86 Laser Safety The Premix cylinder contains Argon and Fluorine Fluorine is toxic High voltage (25,000 to 32,000 volts) Never operate the laser in the presence of flammable anesthetics or other volatile substances such as alcohol Nominal hazard zone is 40 cm
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87 Variable Spot Scanning Combines advantages of larger and smaller diameter beams Allows tissue to be removed in the shortest possible time Smooth ablation
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88 Variable Repetition Rate The repetition rate will vary from 6 to 20 Hz for CustomVue treatments VRR will allow optimal delivery of Variable Spot Scanning (VSS) pulses to ablate tissue in a temporally and thermally efficient fashion
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89 Environmental Conditions Control of environmental conditions during CustomVue treatments is important Temperature should range from 68 to 72º F Relative humidity should range from 40% to 45% Stability of temperature and humidity is important Humidity lower than 40% can lead to overcorrections Humidity higher than 45% can lead to undercorrections
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90 Laser Repetition Rate Conventional Ablations and Phototherapeutic Ablations User can vary Repetition from 1.5 to 10 Hz
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91 Performing the CustomVue Treatment On the STAR Excimer Laser System, select the appropriate CustomVue Treatment by selecting the patient’s name on the Main Menu screen. The CustomVue Treatment calculated on the WaveScan System will appear. The treatment parameters cannot be changed on this screen. Review the information on the laser computer screen to ensure that it is correct.
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92 Flap Hinge Location Select Flap Hinge Location Superior Nasal Temporal LASIK flap hinge location must be entered on the Operating Parameters screen for each CustomVue ™ treatment when using the IR system
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93 Performing the CustomVue Treatment After verifying that this is the appropriate treatment, select TREAT to perform the patient treatment.
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94 Patient Alignment Fiducial Line When the patient is seated in the patient chair, align the patient’s head perpendicular to the system with the fiducial line Fiducial Line Button
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95 Microscope Wild Leica Microscope Variable Magnification –0.63x –1.0x –1.6x –2.5x –4.0x All treatments should be performed at 1.6x magnification
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96 Doctor’s Keypad IR Button ActiveTrak ™ Button Fiducial Line
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97 Joy Stick Joy Stick controls the position of the Patient Chair The microscope does not move Farther = faster
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98 VisionKey Card VisionKey Cards are purchased from AMO Allow use of the STAR S4 IR Excimer Laser VisionKey Cards are laser specific There are different VisionKey Cards for Conventional Ablations CustomVue Ablations CustomVue Retreatments PreVue Lenses Phototherapeutic Keratectomy
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99 Patient Chair Automatic OD/OS pre-positioning Automatic “Y” center button Pillow evacuation button relocated to the left side of the headrest
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100 Operative Illumination Ring Illumination - allows visualization of stromal surface Oblique Illumination - allows visualization of iris and pupil Ring Illumination Oblique Illumination
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101 Operative Illumination Adjust the operative illumination to keep operative pupil diameter as close as possible to WaveScan pupil diameter (between 5 and 7 mm) Use the lowest level of illumination possible to allow patient comfort help with patient fixation on the flashing fixation target
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102 Reticle Reticle is projected into each ocular Reticle can be turned off during Flap creation/reposition Epithelial Removal The Reticle must be on to proceed with the ablation Reticle brightness can be adjusted Reticle Dimensions Inner Ring 4mm Middle Ring 6mm Outer Ring 9mm
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103 Aspirator Aspirator can be moved out of position to allow Creation/reposition of LASIK flap Removal of corneal epithelium The Aspirator must be in the proper position to proceed with the ablation AIRBORNE CONTAMINANTS: Airborne contaminants which are produced by the ablation process are captured in proximity to the cornea near the point of production and fed into an aspirator with a filter. This aspirator is designed to prevent any of the products of ablation from contaminating the surgical suite. Aspirates over 99% of material ejected from the cornea during the ablation
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104 Laser Footswitch Laser Footswitch has two positions First position activates the aspirator Second position activates the laser
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105 ActiveTrak Eye Tracking System
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106 ActiveTrak Eye Tracking System The ActiveTrak System should be used during Conventional and CustomVue Procedures
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107 Moves the laser beam to compensate for eye movements 3D infrared eye tracker Side-mounted infrared cameras monitor x, y, and z (up and down) motion ActiveTrak Eye Tracking System
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108 Side-mounted, infrared cameras monitor x, y, and z movements Oblique IR lighting does not interfere with procedure ActiveTrak Eye Tracking System
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109 Eye movements during LASIK/PRK are followed by the ActiveTrak system such that it: Continues to monitor between pulses Checks eye position at least 3 times for every pulse delivered to the cornea ActiveTrak Eye Tracking System
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110 ActiveTrak Eye Tracking System
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111 The surgeon can choose to set the treatment center manually or use the automatic centering mode. If using automatic centering, the ActiveTrak will locate the pupil and set the treatment center. Automatic Centering should always be used when performing CustomVue Procedures ActiveTrak Eye Tracking System
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112 ActiveTrak Use Press ActiveTrak Button on Doctor’s Keypad The entire reticle will begin flashing The ActiveTrak Eye Tracking System will locate the pupil and set the treatment center
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113 Once the pupil is located, the outside ring on the reticle will stop flashing Once the treatment center is set, the center cross of the reticle stops flashing. The ActiveTrak System will maintain this position throughout the treatment ActiveTrak Use
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114 Fully depress the laser footswitch to begin the treatment The center cross of the reticle will flash slowly during the treatment when the ActiveTrak System is on and tracking the pupil When the ActiveTrak System is activated, you may use the joystick to correct for head (translational) motion during the treatment Do NOT use the joystick to correct for eye rotation when the eye tracker is activated ActiveTrak Use
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115 Treatment will stop or pause when the ActiveTrak™ System detects the following conditions: The patient’s eye moves more than 1.5 mm from the surgeon- selected treatment center (the initial position from which the ActiveTrak™ System begins tracking). The vertical position (z axis) of the corneal surface moves more than 2.0 mm from the initial treatment position. The pupil diameter is not circular to within 32% or becomes smaller than 1.5 mm or larger than 6.0 mm during treatment. Eye motion exceeds 0.2 mm between video frames. Dark objects or reflective objects are in the ActiveTrak™ System’s field of view. Surgical instruments or the surgeon’s hands cross the ActiveTrak™ System’s field of view. ActiveTrak Use
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116 Components of Iris Registration Compensation for Cyclorotation Compensation for Pupil Centroid Shift Ozone Compensation
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117 Registration of CustomVue Ablations WaveScan exams are acquired with the patient in the upright position The CustomVue ablation is performed with the patient in the supine position
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118 Registration of CustomVue Ablations Iris Registration is necessary to compensate for cyclotorsion that occurs when the patient goes from the upright to the supine position
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119 Iris Registration Basic Principles The image of the patient’s eye taken on the WaveScan System is transferred to the STAR S4 IR System along with the CustomVue treatment files via a USB Flash Drive The amount of cyclotorsion of the eye under the laser is determined by comparing features of the iris on the WaveScan image to the same features of the iris on the STAR S4 IR camera image
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120 The iris registration system is only available for CustomVue treatments Re-registration for intra-operative cyclotorsional movement If surgeon tracks significant intra-operative movement, iris image can be re-registered under the laser Iris Registration Basic Principles
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121 There are 48 landmarks used for matching the two iris images 24 landmarks on the WaveScan iris image are matched with 24 landmarks on the STAR S4 IR laser image One landmark for each 15 degree iris sector in each image is identified A minimum of 21 of the 24 landmarks must match It is possible that the laser software will NOT be able to identify enough (or similar) landmarks to allow iris registration to work, regardless of the quality of the WaveScan image Iris Registration Basic Principles
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122 Find multiple matching reference points for each iris section WaveScan Image Laser Image Iris Registration Basic Principles
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123 Torsional Angle Calculate the torsional angles from multiple measurements Iris Registration Basic Principles
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124 Compensation for Pupil Centroid Shift Wavefront measurements and wavefront- guided ablations are typically done under different lighting conditions As a result, the pupil size may be different during measurement and ablation When the pupil size changes the pupil centroid usually shifts
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125 Pupil Centroid Shift Different Lighting Conditions Diagnostic measurement (mesopic) LVC Treatment (photopic) As the pupil changes size, its centroid may not remain stationary, relative to the outer iris boundary Outer Iris Boundary
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126 Iris Registration system compensates for pupil centroid shift by referencing to the outer iris boundary and consistently centering wavefront ablations on the same WaveScan pupil centroid at the laser Iris Registration Compensation for Pupil Centroid Shift
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127 Ozone Compensation Ozone Compensation – As ozone builds up it decreases the amount of energy that passes through the optical pathway Ozone compensation increases energy stability Prior to treatment (patient/plastic) the system will fire ten laser pulses Note: you will hear these additional shots prior to treatment
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128 Iris WaveScan Acquisition Iris Registration WaveScan Acquisition Acquisition of high quality WaveScan images is essential to the success of IR WaveScan Eye Images must be in clear focus with iris details easily visible to facilitate iris capture
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129 When capturing the WaveScan Eye Image, there must be maximum exposure to facilitate proper iris capture –No eyelid artifacts –Little or no cilia –Small lacrimal menisci WaveScan acquisition must be properly centered Visible Purkinje reflections must be crisp and clear Iris WaveScan Acquisition Iris Registration WaveScan Acquisition
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130 A distance of at least 1mm (preferably more) is recommended between the pupil boundary and the upper and lower eyelids Iris Registration WaveScan Acquisition
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131 WaveScan Acquisition Iris and pupil overlays displayed by the software need to match the appropriate structures in the Eye Image The outer iris boundary must be clearly visible and overlying the visible limbal region Eye Images with any boundary misplaced should not be used for treatment
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132 Iris Registration WaveScan ® Acquisition Outer Iris Boundary
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133 Outer Iris Boundary (OIB) Misplaced outer iris boundary can occur at the WaveScan System and/or the laser Both images must be monitored and actively verified
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134 Iris Registration WaveScan Iris Registration WaveScan Acquisition Surgeons must view the actual exam used for treatment design The Green Box in the bottom of the Eye image display indicates that the quality of the selected WaveScan exam is eligible for IR at the laser As the criteria at the laser for IR are more stringent than at the WaveScan, it is possible that IR might not engage at the laser with the green box present IR Eligible IR Not Eligible
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135 Iris Registration Surgical Technique Flap Hinge Location Superior Nasal Temporal LASIK flap hinge location must be entered on the Operating Parameters screen for each CustomVue treatment when using the IR system to identify outer iris boundary
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136 Iris Registration Surgical Technique WARNING As with any surgical procedure, it is ultimately and entirely the STAR S4 IR responsibility of the surgeon to ensure that the CustomVue treatment loaded on the STAR S4 IR System belongs to the correct eye of the correct patient positioned under the laser The "WaveScan Image: Verified" display is an additional criterion used to determine that the WaveScan image associated with the selected treatment matches the image of the patient's eye under the laser Iris matching technologies are probability-based and should not be solely relied on for verification
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137 Iris Iris Registration Prior to engaging the IR system Make certain no surgical instruments or devices are obscuring the IR camera view of the iris, pupil or outer iris boundary –Do not use a Chayet drain or any similar device that can obscure the outer iris boundary or other ocular landmarks –Keep your hands from obscuring the IR camera
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138 Prior to engaging the IR system With the eyelid speculum in position, make certain the cornea is in the middle of the inter-palpebral fissure (primary position) Ensure that the patient’s head is centered and is not tilted to either side Eliminate shadows on the iris or pupil by properly positioning the patient’s head Iris Iris Registration
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139 Iris Registration Optimal Environment Iris Registration Optimal Surgical Environment Operative Illumination Adjust the operative illumination to keep operative pupil diameter as close as possible to WaveScan pupil diameter (between 4 mm and 7 mm) Use the lowest level of illumination possible to –allow patient comfort –help with patient fixation on the flashing fixation target
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140 Optimal Surgical Optimal Surgical Environment Change the illumination as little as possible or preferably not at all after the ActvieTrak System and IR have been engaged. If illumination is changed after engaging the ActiveTrak System and IR, consider restarting the ActiveTrak System and IR
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141 Iris Registration Surgical Technique Center the patient’s eye under the laser and focus on the corneal surface The pupil and iris detail will be slightly out of focus when the laser is properly focused on the corneal surface The IR infrared camera is focused on the iris even though the surgeon is focused on the corneal stromal surface
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142 Procedure should be performed at magnification 16x (the microscope dial may read 16 or 1.6, depending on the system microscope model) Iris Registration Surgical Technique
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143 Significant cyclorotation can occur after the flap is lifted Therefore, Iris Registration and ActiveTrak must be engaged AFTER the flap has been lifted Iris Registration Surgical Technique
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144 Iris Registration Technique Activation of IR System Doctor’s Keypad IR Button ActiveTrakButton Turn on the IR System by pressing the Rotation (Rot) button and the ActiveTrak ™ System by pressing the Track button on the Doctor’s Keypad
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145 Iris Registration Technique Activation of IR System IR should be turned on by pressing the “ROT” button before the ActiveTrak System is activated The ActiveTrak System must be on and tracking to use IR IR will then automatically start when the ActiveTrak System is on and tracking
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146 Patient cooperation and fixation is critically important while IR is engaging Anything that interferes with patient cooperation and fixation while IR is engaging will increase the time of IR capture reduce the success of IR capture Iris Registration Technique Activation of IR System
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147 IR can be re-initiated at any time during the treatment by turning IR off and back on using the “ROT” button When Iris Registration is turned off, the cyclorotation correction and pupil centroid shift are returned to a zero position, just as if Iris Registration had never been on in the first place Iris Registration Technique Activation of IR System
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148 Once IR has been engaged DO NOT reposition the patient’s head If the patient moves after IR has been engaged, IR MUST be restarted Iris Registration Technique Activation of IR System
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149 The dialog box will add the message: “Treatment Registered to WaveScan References. Press footswitch to start treatment.” Fully depress the laser footswitch to begin the treatment This will automatically restore the live microscope camera image Iris Registration Technique Activation of IR System
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150 Iris Technique Iris Registration Technique
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151 Optimizing Iris Registration Three strikes Strike One Check Patient Alignment Confirm Microscope Magnification at 1.6x Focus on anterior stromal surface Re-engage IR
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152 Strike Two Decrease Illumination Re engage IR Strike Three Increase Illumination Re engage If still unsuccessful after three attempts at engaging IR, proceed with CustomVue ablation without IR Optimizing Iris Registration Three strikes
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153 STAR Excimer Laser System Conventional Ablation Dimensions & Shapes
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154 Beam Shaping Iris Diaphragm 2 mm to 6.0 mm diameter for PTK 6 or 6.5 mm diameter for PRK/LASIK Slit Blades PTK (0.6 mm to 6.0 mm) Hyperopic PRK (scanning slit) Iris Diaphragm/Slit Blades PRKa 6 x 4.5 mm or 6.5 x 5.0 mm (minimum minor axis) ellipse
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155 Variable Spot Scanning Blend Zone Variable Slit Scanning Hyperopia Hyperopic Astigmatism Beam Shaping
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156 Ablation Dimensions & Shapes Spherical Myopia Standard Zone 6.0 mm Larger Zone6.5 mm Myopic Astigmatism (Ellipse) Standard Zone 6.0 x 4.5 mm (minimum minor axis) Larger Zone 6.5 x 5.0 mm (minimum minor axis)
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157 Myopic Astigmatism The width of the ellipse is determined by the relationship between sphere and cylinder for any given sphere, the less the cylinder the larger the minor axis Larger Zone treatment depth is 15-20% more than Standard Zone
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158 Ablation Dimensions & Shapes Blend Zone Used in combination with Myopic/Myopic Astigmatic Ablation Can be used with Standard or Larger Zone treatment Last diopter of spherical myopia is treated at 8.0mm diameter Must have one diopter of spherical myopia at the corneal plane
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159 Blend Zone Option with VSS Treatment Profile 1.0 mm Ablation Diameter Blend Zone 8.0 mm Creates gradual slope from optical zone to un-ablated cornea
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160 Blend Zone Option with VSS How Does It Work? Last -1.00 D is treated at 8.0 mm e.g. -6.00 D with Larger Zone and Blend Zone Option Selected –- 5.00 D at 6.5 mm –-1.00 D at 8.0 mm
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161 Treatment Algorithms Myopia < 6.00 D Single Zone 6.0 mm(Standard) 6.5 mm(Larger) > 6.00 D to <12.00 D Multi-zone –6.0/6.5 mm –5.5 mm diameter > 12.00 D Multi-zone –6.0/6.5mm –5.5mm –5.0mm
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162 Myopia/Astigmatism Treatment screen
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163 Myopia/Astigmatism Treatment Screen Desired correction field Enter amount of myopia and astigmatism to be eliminated during the treatment Enter axis of astigmatism Enter vertex distance Enter Ks if not previously entered –(Ks affect the number of pulses delivered to cornea)
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164 Myopia / Astigmatism Treatment Screen A value must be entered in the astigmatism field even if it is zero Results Field Summarizes pulse rate, depth and number of pulses
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165 Myopia with Astigmatism Desired Correction Field The computer will accept a plus cylinder manifest refraction or a minus cylinder manifest refraction in the desired correction field at the spectacle plane NOTE: The final treatment is corrected for the refractive error at the corneal plane expressed in minus cylinder
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166 Ablation Dimensions & Shapes Hyperopia Ablation Diameter9.0 mm Correction Diameter5.0 mm
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167 Hyperopia/Astigmatism Ablation Profile In order to produce a steeper central cornea, the peripheral cornea is flattened Astigmatism is corrected by differentially steepening the flat axis Eccentrically rotating lens in hyperopia module displaces laser beam out to 9 mm Slit blades shape laser beam to rectangular scanning slit
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168 Hyperopia Ablation Profile The ablation extends out to 9.0 mm The zone of deepest treatment is at approximately 5 mm (but may be varied from 3 to 6 mm) Ablation depth at 5 mm is ~ 8 microns/diopter Maximum depth approximately 50 microns
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169 Hyperopia/Astigmatism Treatment Screen
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170 Hyperopia/Astigmatism Ablation Diameters All U.S. clinical trials were conducted at 9 mm total diameter and 5 mm diameter zone of correction No clinical evidence for use of any other size zone. Smaller zones may adversely affect the patient’s optical performance Always verify pupil diameter in bright and dim illumination before treatment
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171 Mixed Astigmatism Cross Cylinder Ablation Cylindrical Steepening with Cylindrical Flattening Example: -1.00 +3.00 x 090 Hyperopic Cylinder Surface Power +2.00 x 090 Myopic Cylinder Surface Power -1.00 x 180
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172 Cross-Cylinder Ablation Profile Cylindrical Steepening with Cylindrical Flattening
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173 Treatment Preferences Page
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174 STAR Excimer Laser System ActiveTrak System Software Any default can be overwritten Surgeon MUST verify all data in every field in every screen
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175 Patient Manager Patient Information Screen
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176 Select Treatment Button Pre-Op Screen
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177 Pre - Operative Examination Screen Refraction Warnings and Yellow bar on bottom left of screen says “ No manifest refraction”
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178 Operative Parameters Screen
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179 Notes Screen N.B., Epithelium Removal is for information on the Operative Report Only - Does Not Control Treatment
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180 Epithelium Removal Screen
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181 Treat Button Treat Button can only be selected from treatment screens
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182 Treatment Summary Screen
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