Corneal Thickness Changes During Corneal Collagen Cross-linking With Ultraviolet-A Irradiation and Riboflavin

Study Overview
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Brief Summary
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The purpose of this study is to evaluate the corneal pachymetric variations during and after corneal collagen cross-linking (CXL) treatment with ultraviolet-A irradiation (UVA) and hypo-osmolar riboflavin solution in thin corneas.

Detailed Description
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To evaluate the corneal pachymetric variations during and after corneal collagen cross-linking (CXL) treatment with ultraviolet-A irradiation (UVA) and hypo-osmolar riboflavin solution in thin corneas. Eighteen eyes of 18 patients, 11 men and 7 women, with progressive keratoconus and thinnest corneal thickness (TCT) less than 400µm were included in this study. After the epithelium removal, iso-osmolar riboflavin was applied to the cornea every 3 minutes (30 min). Hipo-osmolar riboflavin was then applied every 20 seconds until the TCT reached 400µm. UVA irradiation was performed for 30 min. Pachymetry was recorded at the thinnest point of the cornea preoperatively, after epithelial removal, after iso-osmolar riboflavin, after hypo-osmolar riboflavin, after UVA irradiation, and at 1, 6 and 12 months.

Official Title
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Corneal Thickness Changes During Corneal Collagen Cross-linking With Ultraviolet-A Irradiation and Hypo-osmolar Riboflavin Solution in Thin Corneas

Conditions
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Progressive Keratoconus, Thin Corneas

Intervention / Treatment
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* Drug: cross-linking with hypo-osmolar riboflavin


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Progressive Keratoconus thin corneas Exclusion Criteria: Contact lens use for less than 3 weeks Non progressive keratoconus Thinest corneal thickness above 400 micra

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 35 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: crosslinking with hypoosmolar riboflavin<br>Riboflavin and UVA-induced corneal cross-linking increases the stability of keratoconic corneas. The current inclusion criteria require a minimum stromal thickness of 400 µm. Hypo-osmolar riboflavin solution increases the stromal thickness before CXL in cases with preoperatively thin corneas. | Drug: cross-linking with hypo-osmolar riboflavin<br>* Hipo-osmolar riboflavin was applied every 20 seconds until the TCT reached 400µm. UVA irradiation was performed for 30 min. Pachymetry was recorded at the thinnest point of the cornea preoperatively, after epithelial removal, after iso-osmolar riboflavin, after hypo-osmolar riboflavin, after UVA irradiation, and at 1, 6 and 12 months.<br>* Other names: UVA radiation;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Corneal thickness changes during corneal collagen cross-linking with ultraviolet-A irradiation and hypo-osmolar riboflavin solution in thin corneas | To evaluate the corneal pachymetric variations during and after corneal collagen cross-linking treatment with ultraviolet-A irradiation and hypo-osmolar riboflavin solution in thin corneas with progressive keratoconus. | Pachymetry was recorded at the thinnest point of the cornea preoperatively, after epithelial removal, after iso-osmolar riboflavin, after hypo-osmolar riboflavin, after UVA irradiation, and at 1, 6 and 12 months. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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progressive keratoconus, thin corneas, cross-linking, hypo-osmolar riboflavin