Corneal Sensitivity Cross-linking Keratoconus

Study Overview
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Brief Summary
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To evaluate corneal sensitivity changes following corneal cross-linking (CXL) in patients with progressive lower stage keratoconus.

Detailed Description
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Thirty eight eyes of 19 patients (11 women, 8 men) were included in a prospective, nonrandomized clinical study. Mean patient age was 22 years (range, 18-26 years). Inclusion criteria were low stage bilateral progressive keratoconus, transparent cornea and thinnest corneal thickness ≥ 440 µm. Using the Cochet-Bonnet esthesiometer central corneal sensitivity was measured preoperatively, after 7 days, and once a month after surgery until recovery of the baseline preoperative level. Normal levels of central corneal sensitivity were considered above 40mm.

Official Title
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Corneal Sensitivity Changes Following Cross-linking for Progressive Lower Stage Keratoconus

Conditions
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Keratoconus

Intervention / Treatment
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* Other: Cochet-Bonnet esthesiometer central corneal sensitivity


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Be at least 18 years of age Provide written consent and sign a HIPAA form Willingness and ability to follow all instructions and comply with schedule for follow-up visits For females capable of becoming pregnant,agreet o have uurine pregnancy testing performed prior to treatment; must not be lactating, and must agree to use a medically acceptable form of birth control for at least one week prior to the treatment and continue to use the method until 1 month after the last dose of investigational product. Having topographic evidence of keratoconus which is graded as lower stage progressive keratoconus Presence of central or inferior steepening on the Pentacam map Steepest keratometry (Kmax) value greater than or equal to 51.00D BSCVA of 80 letters or fewer for keratoconus on ETDRS chart Contact lens wearers only: remove contact lenses one week prior to the screening refraction Contact lens wearers only: manifest refraction must be stable between two visits that occur at least 7 days apart Exclusion Criteria: Contraindications, sensitivity or known allergy to the use of the test articles(S) or their components If female, be pregnant, nursing, or planning a pregnancy or have a positive urine pregnancy test at Visit 2 prior to treatment or during the course of the study Eyes classified as either normal,atypical normal,keratoconus suspect or mild keratoconus on the severity grading scheme A history of the insertion of INTACS in the eye to be treated A history of previous limbal relaxing incision procedure in the eye to be treated Corneal pachymetry that is <350 microns at the thinnest point measured by Pentacam in the eye to be treated Eyes which are aphakic Eyes which are pseudophakic and do not have a UV blocking lens implanted Previous ocular condition (other than refractive error) in the eye to be treated that may predispose the eye for future complications. A history of delayed epithelial healing in the eye to be treated Patients with nystagmus or any other condition that would prevent a steady gaze during the treatment or other diagnostic tests Patients with a currnet condition that, in the investigator's opinion,would interfere with or prolong epithelial healing Taking Vitamin C (ascorbic acid) supplements within 1 week of the crosslinking treatment A history of previous corneal crosslinking treatment in the eye to be treated Have used an investigational drug or device within 30 days of the study or be concurrently enrolled in another investigational drug or device study within 30 days of the study

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 26 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: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Sensitiviy<br>Using the Cochet-Bonnet esthesiometer central corneal sensitivity was measured preoperatively, after 7 days, and once a month after surgery until recovery of the baseline preoperative level. Normal levels of central corneal sensitivity were considered above 40mm. | Other: Cochet-Bonnet esthesiometer central corneal sensitivity<br>* Using the Cochet-Bonnet esthesiometer central corneal sensitivity was measured preoperatively, after 7 days, and once a month after surgery until recovery of the baseline preoperative level. Normal levels of central corneal sensitivity were considered above 40mm.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Corneal sensitivity | To evaluate corneal sensitivity changes following corneal cross-linking (CXL) in patients with progressive lower stage keratoconus. | Central corneal sensitivity was measured preoperatively, after 7 days, and once a month after surgery until recovery of the baseline preoperative level. The avarage was 12 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Corneal sensitivity, Cross-linking, Keratoconus