MyoRing Implantation With Corneal Collagen Crosslinking for Keratoconus

Study Overview
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Brief Summary
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A complete intrastromal ring, MyoRing (Dioptex, GmbH, Linz, Austria), suggested by Albert Daxer in 2007, is a relatively new technique that has been demonstrated to treat keratoconus safely and effectively.Corneal collagen crosslinking (CXL), introduced by Wollensak et al. in 2003, has become a standard treatment for progressive keratoconus to slow or possibly stop progression of disease. The formation of the stromal pocket during MyoRing implantation offers the opportunity for simultaneous introduction of riboflavin 0.1% into the pocket followed by UVA irradiation to provide combined treatment in patients with progressive keratoconus.

Official Title
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Complete Corneal Ring (MyoRing) Implantation Combined With Corneal Collagen Crosslinking for Keratoconus

Conditions
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Keratoconus

Intervention / Treatment
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* Procedure: Corneal Collagen Crosslinking
* Device: Ufalink


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: >18 years old a diagnosis of keratoconus, intolerance for contact lenses or glasses a documented progression of disease. This progression was defined by the following changes over 1 year: an increase of the steepest K by 1.0 diopter (D) or more in manifest cylinder, or an increase of 0.5 D or more in manifest spherical equivalent (SE) refraction by repeated keratotopography ODP-scan ARK-1000 (Nidek, Japan) Exclusion Criteria: minimal pachymetry of less than 380 μm, a history of previous ocular pathology or ocular surgery; pregnancy or breastfeeding; corneal scarring.

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: MyoRing Implantation combined with corneal cross linking<br>Surgical technique: Implantation of a MyoRing in a corneal pocket was performed by using a PocketMaker microkeratome a guided, vibrating diamond blade to create a stromal pocket 9 mm in diameter at a 300-μm depth via a 4- to 5-mm-wide corneal tunnel followed by Corneal Collagen Crosslinking (standard surface UVA irradiation (370 nm, 3 mW/cm2) using Ufalink device) | Procedure: Corneal Collagen Crosslinking<br>* Sterile riboflavin solution 0.1% was then continuously injected for 3 minutes into the corneal pocket via a standard 0.3-mm cannula through the incision tunnel. Standard surface UVA irradiation (370 nm, 3 mW/cm2) was then applied at a 5-cm distance for 30 minutes. After UVA irradiation, a flexible MyoRing intracorneal implant was inserted into the corneal pocket,<br>Device: Ufalink<br>* UVA irradiation with wave length 370 nm, 3 mW/cm2 is provided with UFalink, device,Russian Federation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| K max | Using topography measurements, decrease of maximum keratometry value over the preoperative maximum keratometry value | 2 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visual acuity as assessed by Decimal system | Decimal visual acuity assessed on a study later was converted to the logarithm of minimal angle of resolution (logMAR). | 2 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Keratoconus, riboflavin, corneal collagen crosslinking, intrasromal ring