Comparative Analysis of the Visual Performance After TICL Implantation in Patients With Stable Keratoconus

Study Overview
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Brief Summary
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To report on 4-year postoperative safety, efficacy, stability and predictability outcomes(to evaluate the visual, refractive, contrast sensitivity, defocus curve and aberrometric data preoperation, and compare with a similar postoperative outcomes) with the Toric Implantable Contact Lens (TICL) for Stable keratoconus. Investigators will study the four-year follow-up from this standardized, multi-center clinical investigation, support from clinical and optical viewpoints TICL implantation, in stable keratoconus.

Official Title
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Comparative Analysis of the Visual Performance in Patients With Stable Keratoconus After Implantation of the Toric Implantable Collamer Lens (TICL).

Conditions
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Keratoconus

Intervention / Treatment
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* Device: Toric Implantable collamer Lens


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age (25-38). Stable refraction was distinctive by 6 subjective refractions within ± 0.50 diopters(D) of spherical equivalent during 6 months after CXL. best spectacle-corrected visual acuity (BCVA) of +0.4 LogMAR (20/40) or better, -clear central cornea. normal anterior chamber depth at least 3 mm to endothelium . intraocular pressure (IOP)<20 mm Hg and preoperative endothelial cell count related to age and the anterior chamber depth with regard to Food and Drug Administration recommendations. Width of Angle greater than 30°, a pupil diameter of less than 6.25 mm. Exclusion Criteria: Patients with central corneal thickness of less than 450 μm. endothelial cell count of less than 2,000 cells/mm2 . anterior chamber depth of <3 mm from endothelium to anterior capsule . Corneal opacification or scars, cataract, retinal detachment, glaucoma, retinopathy, macular degeneration, neuro ophthalmic diseases or ocular inflammation, history of keratitis (any form), peripheral marginal degeneration, previous corneal and/or intraocular surgeries, and autoimmune and/or connective tissue disease. The central corneal thickness limit of 450 μm would account for around 400 μm of remaining stromal thickness after removal of the epithelium, which is considered as the safety thickness for the residual stroma to avoid endothelial cell damage during the CXL procedure.

Ages Eligible for Study
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Minimum Age: 25 Years
Maximum Age: 38 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

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: Toric Implantable contact Lens<br>The Visian implantable collamer lens (Staar Surgical AG, Nidau, Switzerland), is a monoblock single-piece plate haptic lens made of collamer (an extremely hydrophilic and highly biocompatible flexible collagen copolymer with a refractive index of 1.452 that is permeable to oxygen and nutrients | Device: Toric Implantable collamer Lens<br>* The toric implantable collamer lens (TICL) is conventionally indicated for the Correcting the refractive error in keratoconus using the TICL is an off label use of the lens.<br>* Other names: TICL;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visual acuity (UCVA,BCVA) by Snellen chart |  | Up to 4 years after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Refractive error by Auto Kerato-Refractometer |  | Until 4 years after surgery | 
| Defocus curve by Phoropter |  | Up to 4 years after surgery | 
| Patient satisfaction to measure the patients' subjective assessment of visual improvement by a validated questionnaire |  | up to 4 years after surgery | 
| Contrast sensitivity by MediWorks C901 Acuity Chart (Shanghai MediWorks Precision Instruments Co, Ltd, Shanghai, China. |  | up to 4 years after surgery | 
| Aberrometry by Ray Tracing |  | Up to 4 years after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Keratoconus, Crosslinking, Toric ICL