Epi-on PiXL for the Treatment of Progressive Keratoconus.

Not Applicable

Active, not recruiting

• Conditions: Keratoconus; Corneal Crosslinking; Corneal Densitometry; Eye Diseases; Scheimpflug Photography; Corneal Disorder
• Interventions: Procedure: Epi-on PiXL in high oxygen

• Registration Number: NCT04668924
• Lead Sponsor: Umeå University

Brief Summary

The purpose of this study is to evaluate the efficacy, safety and postoperative ocular discomfort by individually customized Photorefractive intrastromal crosslinking (PiXL) without epithelium debridement in high oxygen environment (Epi-on) for progressive Keratoconus.

Detailed Description

The study is designed as a prospective, open-label, nonrandomized trial involving participants of both genders aged 18-35 years with Keratoconus planned for routine corneal crosslinking at the Department of Ophthalmology, Umeå University Hospital, Umeå, Sweden.

The study includes 30 participants with unilateral Keratoconus, receiving Epi-on PiXL in high oxygen environment (n=30). All patients are informed about the procedures before consenting to participate in the study.

At baseline, before treatment, each eye is examined with slit-lamp microscopy, subjective refraction, determination of uncorrected (UCVA), low contrast visual acuity at 2.5 percentage contrast and 10 percentage contrast and best corrected (BSCVA) visual acuities using the LogMAR fast protocol and intraocular pressure (IOP) using Goldmann applanation tonometry. Under standardized, mesopic light conditions each eye is evaluated by keratometry readings and central corneal thickness, extracted from Schemipflug camera measurements, Pentacam HR® (Oculus, Inc. Lynnwood, WA) and AS-OCT (Fourier domain OCT CASIA2, Tomey Technology and vision, Germany).

Central corneal endothelial photographs are taken with the Topcon SP-IP specular microscope (Topcon Europe B.V., Capelle a/d Ijssel, the Netherlands) and total ocular wavefront is measured with iTrace (Tracey Technologies, Inc.).

Ocular discomfort is subjectively evaluated in each eye by a specific visual analogous rating scale at 4h, 8h, 12h, 24h and thereafter daily up to 1 week postoperatively.

All the above mentioned examinations are repeated at 1, 3, 6, 12 and 24 months after treatment. At 1 day and 1 week after treatment, solely UCVA, Auto refractor measurements, slit-lamp examination are evaluated.

Study Timeline

• Study Start: 2019-03-20
• Study First Submitted: 2020-12-09
• Study First Submitted QC: 2020-12-09
• Study First Posted: 2020-12-16
• Status Verified: 2023-12
• Last Update Submitted: 2023-12-19
• Last Update Posted: 2023-12-20
• Primary Completion: 2026-02-05
• Study Completion: 2026-02-05

Recruitment & Eligibility

• Status: ACTIVE_NOT_RECRUITING
• Sex: All
• Target Recruitment: 32

Inclusion Criteria

• Patients planned for corneal crosslinking.
• Progressive keratoconus documented with a consistent decrease of best corrected visual acuity with no other explanation, an unquestionable historical progression, or a progression documented with the Pentacam Scheimpflug camera with at least 2 of the following: progressive anterior and/or posterior corneal steepening and/or progressive corneal thinning and/or increased rate of corneal thickness change from the periphery to the center.
• A keratoconus diagnosis based on abnormal posterior elevation, abnormal corneal thickness distribution and clinical noninflammatory corneal thinning using the "Belin/Ambrósio enhanced ectasia" measurements of the Pentacam Scheimpflug camera.
• Minimum corneal thickness of 400 µm at the thinnest point before epithelial removal.
• 18-35 years of age
• No ocular abnormalities except keratoconus
• No previous ocular surgery
• No cognitive insufficiency interfering with the informed consent.

Exclusion Criteria

• Age under 18 or over 35
• Any corneal abnormalities except keratoconus
• Pregnancy or lactation
• Previous ocular surgery
• Cognitive insufficiency

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Epi-on PiXL in high oxygen	Epi-on PiXL in high oxygen	Photorefractive intrastromal corneal crosslinking without epithelium debridement during humidified high oxygen flow.

Primary Outcome Measures

Name	Time	Method
Keratometry readings	1, 3, 6, 12 and 24 months after treatment	Change from baseline in Keratometry readings, Kmean (average), K1 (flat meridian), K2 (steep meridian) and Kmax (steepest radius of curvature) assessed with the Pentacam HR Scheimpflug camera
Uncorrected Distance Visual Acuity (UDVA)	1, 3, 6, 12 and 24 months after treatment.	Change from baseline in Uncorrected Distance Visual Acuity

Secondary Outcome Measures

Name	Time	Method
Manifest Refractive Spherical Equivalent (MRSE)	1, 3, 6, 12 and 24 months after treatment.	Change from baseline in Manifest Refractive Spherical Equivalent
Corneal Endothelial cell density (ECC)	12 and 24 months after treatment	Change from baseline in corneal endothelial cell density
Subjective Ocular Discomfort Scores	4, 8h and 1, 2, 3, 4, 5, 6 and 7 days after treatment.	Change in a Ocular Discomfort Visual Analogous Scale after treatment.
Best Spectacle Distance Visual Acutiy (BSCVA)	1, 3, 6, 12 and 24 months after treatment.	Change from baseline in Best Spectacle Distance Visual Acutiy

Trial Locations

Locations (1)

Umeå University Hospital; 🇸🇪 Umeå, Sweden