PiXL for Correction of Hyperopia

Study Overview
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Brief Summary
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This clinical study aims to investigate the efficacy and safety of PiXL in the refractive correction of low hyperopia.

Detailed Description
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This clinical study aims to investigate the efficacy and safety of PiXL in the refractive correction of low hyperopia.Slightly modified settings from previously published study is applied to eyes with low hyperopia with an expected refractive change of 0.75 D. Aim is to evaluate the refractive outcome of this procedure.

Official Title
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Photorefractive Intrastromal Corneal Crosslinking (PiXL) for Correction of Hyperopia

Conditions
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Hyperopia

Intervention / Treatment
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* Radiation: PiXL


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: low hyperopia of spherical equivalent from +0.5 up to +1.75 D sp. eq. astigmatism up to 0.75 Dcyl corneal thickness above 400 µm endothelial cell density above 1500 cell/mm2 Exclusion Criteria: any prior corneal surgery or any eye surgery within the last 3 months, any corneal pathology e.g. corneal scar or dystrophy unstable refraction patient not able to understand and sign informed consent patients with connective tissue disorder or uncontrolled diabetes pregnant or lactating women aphakic eyes or pseudophakic eyes without UV blocking IOL

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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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Photorefractive intrastromal corneal crosslinking (PiXL)<br>Patients undergo PiXL where the UVA light is delivered in customized patterns and corneal changes are achieved. For hyperopia, a ring shape irradiation is used to steepen the central cornea. An oxygen mask is used to enhance the crosslinking efficacy. A dedicated riboflavin formulation penetrates the corneal stroma. Pulsed UVA light with oxygen triggers the covalent bonds of collagen strands in riboflavin soaked cornea. | Radiation: PiXL<br>* The system is set to deliver 30 mW/cm2 UVA irradiance in pulsed intervals of 1 second on and 1 second off to 5 to 9 mm diameter corneal annulus. Total energy delivered is 15J.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Uncorrected Distance Visual Acuity | Best distance visual acuity tested without any correction | Month 12 | 
| Change in Subjective Refraction | Spherical and cylindrical correction | Month 12 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in keratometry | Change in keratomery parameter K2-K1provided by Pentacam | Month 12 | 
| Change in Higher Order Aberrations | Higher Order Aberrations assessed using Pentacam | Month 12 | 
| Change in pachymetry | Change in mean cornea thickness in 8.0 mm ring provided by Pentacam | Month 12 | 
| Subjective questionnaire score | Questionnaire assessing participants discomfort at 6 months in respect to their photophobia, pain and dry eye. | Month 12 | 
| Change in Corrected Distance Visual Acuity | Best distance visual acuity tested with the best correction | Month 12 | 
| Change in Spherical aberration | Spherical aberration assessed using Pentacam | Month 12 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hypeorpia, Crosslinking, PiXL