Chromatic and Monochromatic Optical Aberrations After Corneal Refractive Surgery

Study Overview
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Brief Summary
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Refractive surgeries can be divided into two distinct categories: 1) corneal surgeries (superficial and deep procedures) carried on the surface of the eye and 2) lens surgeries (phakic IOL, refractive lens exchange) - an intraocular intervention, performed in the anterior or posterior chamber or on the lens. In the proposed protocol focus is on the corneal refractive surgeries impact on monochromatic higher-order aberrations on the one hand and chromatic aberrations on the other. During the surgery in order to get the patient emmetropic, refractive surgery corrects optical defects by decreasing aberrations of lower orders ) simultaneously increases high-order aberrations (that is perceived by the patient as halo, glare or starburst). Informations about prevalence and causes of higher order aberrations after refractive surgery are numerous but there is no information about chromatic aberrations.

Official Title
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Chromatic and Monochromatic Optical Aberrations After Corneal Refractive Surgery - Preliminary Study Assessing Their Prevalence, Methods of Reductions of Symptoms and Time-dependent Changes in Patients Symptoms

Conditions
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Refractive Errors, Aberration, Corneal Wavefront

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patient after corneal refractive surgery at least for 4 months post surgical refraction within +/- 0.75 diopter of spherical and +/- 1.0 diopter of cylindrical error willing and able to understand and sign an informed consent form. Exclusion Criteria: patient unable to participate in the study any corneal diseases, eyes trauma or systemic diseases history; keratoconus or tendency of keratoconus corneal macula and obvious pannus; current enrolment in another clinical trial/research project

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Post refractive surgery without HOA<br>Patients post refractive surgery that do not complain on the high order aberrations such as glare, halo and starburst. | |
| Post refractive surgery with HOA<br>Patients post refractive surgery that do complain on the high order aberrations such as glare, halo and starburst. | |
| Post refractive surgery with rainbow HOA<br>Patients post refractive surgery that do complain on: the high order aberrations such as glare, halo and starburst but with the chromatic aureola difficulties working with LCD projectors, monitors, cell phones and tablets | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| number of high order and chromatic aberrations after refractive surgery | number of high order and chromatic aberrations after refractive surgery | 6 months | 
| Chromoretinoscopy for near (MEM) and distance | Conducted with a modified by researchers retinoscopy with distinct filters | 6 months | 
| Aberrometry reading for corneal HOA | Conducted with aberrometer and corneal tomography | 6 months | 
| Transverse chromatic aberration | Conducted with a modified by researchers aniseikonia test (with red and green lenses) | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Hue 100 test | without and after the introduction of glasses with accommodation support, a blue light filter or concave lenses up to -0,5 diopter | 6 months | 
| Change of contrast sensitivity for near vision | without and after the introduction of glasses with accommodation support, a blue light filter or concave lenses up to -0,5 diopter | 6 months | 
| Visual Function Questionaire 25 | Conducted with VFQ-25 test | 6 months |