Impact of Keratoconus, Cross-linking and Cross-linking Combined With Topo-guided Photorefractive Keratectomy on Self-reported Quality of Life. A Three-year Update.

Study Overview
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Brief Summary
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Study Hypothesis: Former investigators indicated that keratoconus has a negative impact on vision-specific quality of life. This study attempts to confirm this statement and assess whether cross-linking and cross-linking combined with photorefractive keratectomy improve vision-specific quality of life, in a sample of keratoconus patients with 3-years follow-up.

Official Title
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Impact of Keratoconus, Cross-linking and Cross-linking Combined With Topo-guided Photorefractive Keratectomy on Self-reported Quality of Life. A Three-year Update.

Conditions
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Keratoconus

Intervention / Treatment
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* Procedure: Corneal Cross Linking
* Procedure: Corneal Cross Linking combined with topoguided PRK


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: be diagnosed and classified as stage 1 keratoconus according to the Amsler-Krumeich classification system for keratoconus present progressive keratoconus in consecutive corneal topographies, and/or changes in their refractive power. Progressive keratoconus was defined when any of the following criteria was met for a period of 24 months: an increase of 1.00 diopter (D) or more in the steepest keratometry measurement an increase of 1.00 D or more in manifest cylinder an increase of 0.50 D or more in manifest refraction spherical equivalent. Exclusion Criteria: glaucoma suspicion for glaucoma IOP-lowering medications central corneal thickness (CCT) less than 400μm K-readings more than 60D history of herpetic keratitis corneal scarring severe eye dryness pregnancy or nursing current corneal infection or underlying autoimmune disease KG members were further sub-divided into CxL and tCxL groups, according to their eligibility for treatment with CxL or CxL with tPRK. In order to be eligible for tCxL, group participants should, additionally, have CCT above 450μm.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 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: Health Services Research
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Cross Linking Group (CxL group)<br>Patients that received CXL | Procedure: Corneal Cross Linking<br> <br> |
| Active Comparator: Cross Linking with topo-guided PRK (tCxL)<br>Patients that received tCxL | Procedure: Corneal Cross Linking combined with topoguided PRK<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Vision Specific quality of Life (VS-QoL) |  | 3 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Keratoconus, Corneal cross Linking, Topo guided PRK, Quality of Life