WaveLight® Refractive Flap Accuracy Study

Not Applicable

Completed

• Conditions: Refractive Error
• Interventions: Device: WaveLight® Refractive Suite; Procedure: LASIK surgery

• Registration Number: NCT01941485
• Lead Sponsor: Alcon Research

Brief Summary

The purpose of this study is to evaluate the accuracy of the WaveLight FS200 femtosecond laser, as assessed by 1 day and 1 month post-operative optical coherence tomography (OCT) anterior segment corneal measurements compared to pre-operative flap thickness target.

Detailed Description

Not available

Basic Information
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Recruitment & Eligibility
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Study & Design

Study Timeline

• Study First Submitted: 2013-09-10
• Study First Submitted QC: 2013-09-10
• Study First Posted: 2013-09-13
• Study Start: 2013-10
• Primary Completion: 2014-01
• Study Completion: 2015-02
• Results First Submitted: 2015-02-01
• Results First Submitted QC: 2015-02-01
• Results First Posted: 2015-02-12
• Status Verified: 2016-11
• Last Update Submitted: 2016-11-07
• Last Update Posted: 2017-01-04

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 60

Inclusion Criteria

• Willing and able to understand and sign an informed consent form.
• Have refractive error (in both eyes) that requires refractive surgery.
• Willing to undergo LASIK surgery using the Wavelight® Refractive Suite.
• Myopia between 0.00 to -12.0 Diopters pre-operatively.
• Astigmatism between 0.00 to +6.00 Diopters pre-operatively.
• Willing and able to attend post-operative examinations per protocol schedule.
• Other protocol-defined inclusion criteria may apply.

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Exclusion Criteria

• Participation in a clinical study within the last 30 days.
• History of previous corneal surgery in either eye.
• Multifocal ablations in either eye.
• PRK or PTK surgery in either eye.
• Suffering from acute or recurring eye diseases in either eye, such as corneal ulcers, cataract, etc.
• Any ocular disease and/or condition that, in the Investigator's clinical judgment, may put subject at significant risk, compromise study results, or interfere significantly with subject's participation in the study.
• Unable to discontinue contact lens wear as specified in protocol.
• History of Herpes simplex or Herpes zoster keratitis.
• Active ocular rosacea.
• Lyme disease.
• Severe ocular allergies.
• Other medical conditions and use of medications as specified in protocol.
• Pregnant or planning to become pregnant during the study.
• Other protocol-specified exclusion criteria may apply.

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Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
WaveLight Refractive Suite	WaveLight® Refractive Suite	LASIK surgery (laser in situ keratomileusis) per standard of care
WaveLight Refractive Suite	LASIK surgery	LASIK surgery (laser in situ keratomileusis) per standard of care

Primary Outcome Measures

Name	Time	Method
The Difference Between Achieved Flap Thickness at Day 1 Postoperative as Assessed by OCT and Expected Flap Thickness as Determined Pre-operatively	Day 1 Postoperative	The expected flap thickness as determined pre-operatively was subtracted from the achieved flap thickness at Day 1 postoperative as assessed by optical coherence tomography (ie, an imaging method using light to capture three-dimensional images). Accuracy of flap creation was defined as an achieved thickness within 10 microns of expected thickness.

Secondary Outcome Measures

Name	Time	Method
Manifest Refraction (Cylinder)	Baseline/Screening (Day 0), Month 1 Postoperative, Month 3 Postoperative, Month 6 Postoperative, Month 12 Postoperative	A series of test lenses in graded powers was used to determine which corrective lenses provided the sharpest, clearest vision. Manifest refraction is measured in diopters. Each eye contributed individually to the analysis.
Wavefront Aberrometry	Operation/Surgery (Day 1), Month 1 Postoperative, Month 6 Postoperative, Month 12 Postoperative	Wavefront aberrations (optical imperfections of the eye that prevent light from focusing perfectly on the retina, resulting in defects in the visual image) were measured using a commercially available system. Higher order aberrations (i.e., spherical aberrations, coma, and trefoil) are defined as optical imperfections which cannot be corrected by any reliable means of present technology.
Incidence of Development of Opaque Bubble Layer (OBL)	Operation/Surgery (Day 1)	OBL (the collection of gas bubbles during corneal flap creation) was assessed by digital photo analysis of the area covered by the flap and is reported as the percentage of participants with opaque bubble layer development during femtosecond flap creation.
Extent of Opaque Bubble Layer (OBL) Within the Femtosecond Flap	Operation/Surgery (Day 1)	The extent of OBL was assessed by digital photo analysis of the area covered by the flap and is reported as the percentage of flap with opaque bubble layer development during femtosecond flap creation.
The Difference Between Achieved Flap Thickness at Month 1 Post-operative as Assessed by OCT and Expected Flap Thickness as Determined Preoperatively	Month 1 Postoperative	The expected flap thickness as determined pre-operatively subtracted from the achieved flap thickness at Month 1 postoperative as assessed by optical coherence tomography (ie, an imaging method using light to capture three-dimensional images). Accuracy of flap creation was defined as an achieved thickness within 10 microns of expected thickness.
Manifest Refraction (Sphere)	Baseline/Screening (Day 0), Day 1 Postoperative, Month 1 Postoperative, Month 3 Postoperative, Month 6 Postoperative, Month 12 Postoperative	A series of test lenses in graded powers was used to determine which corrective lenses provided the sharpest, clearest vision. Manifest refraction is measured in diopters. Each eye contributed individually to the analysis.
Corneal Topography: Q-value	Day 1 Postoperative, Month 1 Postoperative, Month 3 Postoperative, Month 6 Postoperative, Month 12 Postoperative	The Q-value (a measure of corneal asphericity) was assessed using a commercially available system. The Q-values are negative (-1 \< Q \< 0) for prolate corneas, in which the central curvature is steeper than the peripheral curvature, and positive (Q \> 0) for oblate corneas, in which the central curvature is flatter than the peripheral curvature.
Uncorrected Visual Acuity (UCVA)	Baseline/Screening (Day 0), Day 1 Postoperative, Month 1 Postoperative, Month 3 Postoperative, Month 6 Postoperative, Month 12 Postoperative	Visual acuity (VA) without spectacles or other visual corrective devices, was performed with an Early Treatment Diabetic Retinopathy Study (ETDRS) chart set at a distance of 4 meters. UCVA was measured in logMAR (logarithm of the minimum angle of resolution), with 0.00 logMAR corresponding to 20/20 Snellen. A lower logMAR value indicates better visual acuity.
Best Corrected Visual Acuity (BCVA)	Baseline/Screening (Day 0), Day 1 Postoperative, Month 1 Postoperative, Month 3 Postoperative, Month 6 Postoperative, Month 12 Postoperative	VA with the subjects's best spectacles or other visual corrective devices, was performed with an ETDRS chart set at a distance of 4 meters. BCVA was measured in logMAR (logarithm of the minimum angle of resolution), with 0.00 logMAR corresponding to 20/20 Snellen. A lower logMAR value indicates better visual acuity.
Mean Response: "Rate Your Vision, Over the Past 4 Weeks, With NO Glasses or Contact Lenses"	Baseline/Screening (Day 0), Month 1 Postoperative, Month 6 Postoperative, Month 12 Postoperative	As recorded by the subject on the the Refractive Status and Vision Profile (RSVP), a self-reported questionnaire used to measure vision-related health status in persons with refractive error, on a scale from 0 (completely blind) to 10 (perfect vision).
Percent Response by Category: "My Vision is a Concern in my Daily Life"	Baseline/Screening (Day 0), Month 1 Postoperative, Month 6 Postoperative, Month 12 Postoperative	As recorded by the subject on the RSVP questionnaire
Percent Response by Category: "Driving at Night"	Baseline/Screening (Day 0), Month 1 Postoperative, Month 6 Postoperative, Month 12 Postoperative	As recorded by the subject on the RSVP questionnaire, where 0 is "Not applicable", 1 is "No difficulty at all", 2 is "A little difficulty", 3 is "Moderate difficulty", 4 is "Severe difficulty" and 5 is "So much difficulty that I did not do the activity with this alternative".
Flap Creation Time as Documented in the Log Files	Operation/Surgery (Day 1)	The time to create the flap with FS200 Femtosecond Flap Creation System, measured in seconds.
Mean Contrast Sensitivity (CS)	Baseline/Screening (Day 0), Month 1 Postoperative, Month 3 Postoperative, Month 6 Postoperative, Month 12 Postoperative	Contrast sensitivity (ie, the ability to detect slight changes in luminance before they become indistinguishable) was assessed binocularly with distance manifest correction in place and uncorrected. Contrast sensitivity was assessed at spatial frequencies of 3, 6, 12, and 18 cycles per degree (cpd), where 3.0 cpd = A, 6.0 cpd = B, 12.0 cpd = C, and 18.0 cpd = D. Raw scores were log transformed. A higher numeric value represents better contrast sensitivity. Both eyes contributed to the analysis.
Corneal Flap Diameter as Assessed by Ocular Coherence Tomography (OCT)	Operation/Surgery (Day 1), Day 1 Postoperative, Month 1 Postoperative, Month 3 Postoperative, Month 6 Postoperative, Month 12 Postoperative	The diameter of the corneal flap was assessed by OCT (ie. an imaging method using light to capture three-dimensional images). Corneal flap is measured in millimeters.
Percent Response to "Have Always Worn Glasses or Contact Lenses in the Past 4 Weeks"	Baseline/Screening (Day 0), Month 1 Postoperative, Month 6 Postoperative, Month 12 Postoperative	As recorded by the subject on the the Refractive Status and Vision Profile (RSVP), a self-reported questionnaire used to measure vision-related health status in persons with refractive error.
Percent Response by Category: "I Worry About my Vision"	Baseline/Screening (Day 0), Month 1 Postoperative, Month 6 Postoperative, Month 12 Postoperative	As recorded by the subject on the RSVP questionnaire
Corneal Curvature as Measured by Keratometry	Baseline/Screening (Day 0), 1 Month Postoperative, Month 3 Postoperative, Month 6 Postoperative, Month 12 Postoperative	Corneal curvature as assessed by a commercially available system and measured in diopters.
Corneal Topography: Anterior Chamber (AC) Volume	Day 1 Postoperative, Month 1 Postoperative, Month 3 Postoperative, Month 6 Postoperative, Month 12 Postoperative	The AC volume (a measure of the shallowness of the anterior chamber) was assessed using a commercially available system. The lower the chamber volume, the more shallow the anterior chamber or the chamber angle.
Corneal Topography: Anterior Chamber (AC) Depth	Day 1 Postoperative, Month 1 Postoperative, Month 3 Postoperative, Month 6 Postoperative, Month 12 Postoperative	The AC depth (axial distance between the anterior surface of the cornea and the anterior surface of the lens) was assessed using a commercially available system. A higher value represents a longer distance.
Corneal Topography: Angles	Day 1 Postoperative, Month 1 Postoperative, Month 3 Postoperative, Month 6 Postoperative, Month 12 Postoperative	The angles (angular measurement of the space between the iris and the lens) were assessed using a commercially available system. The higher the value, the bigger the space.