The Effect of Mitomycin C on Corneal Haze and Scarring After Corneal Crosslinking in Keratoconus Patients

Keratoconus Clinical Trial

Official title:

The Effect of Mitomycin C on Corneal Haze and Scarring After Corneal Crosslinking in Keratoconus Patients

Clinical Trial Details — Status: Terminated

Administrative data

• NCT number: NCT04811924
• Other study ID #: CXLMMC2020
• Status: Terminated
• Phase: Phase 2
• Start date: July 26, 2021
• Est. completion date: February 22, 2023

Study information

• Verified date: February 2023
• Source: Ciusss de L'Est de l'Île de Montréal
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Corneal crosslinking (Crosslinking, CXL) is a treatment offered for the stabilization of early corneal ectatic disorders such as keratoconus. Although CXL is an excellent treatment option to stabilize early ectatic corneas, complications include corneal haze, sterile infiltrate, endothelial cell toxicity, treatment failure and stromal scarring. Corneal haze is a common finding in almost all CXL patients and may decrease visual quality. The effect of 0.02% mitomycin C (MMC) for 2 minutes on corneal haze and scarring in refractive surgery is well established in the literature with many clinical studies confirming its effectiveness. Although the pattern of corneal haze after CXL appears to be different from the haze pattern seen following refractive procedures, both processes are thought to be caused by an inflammatory response.

The investigators postulate that MMC can reduce post-CXL haze and scars when using the optimal concentration and duration of exposure.

Recruitment information / eligibility

• Status: Terminated
• Enrollment: 4
• Est. completion date: February 22, 2023
• Est. primary completion date: February 22, 2023
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years to 70 Years

Eligibility

Inclusion Criteria:

• Patients from both genders with confirmed keratoconus with evidence of clinical and topographic progression.

• Patients with the diagnosis of other ectatic disorders such as post refractive surgery ectasia with evidence of clinical and topographic progression.

Exclusion Criteria:

• Patients who are pregnant

• Patients who are breast-feeding

• Patients who have allergy to MMC

• Patients with other corneal conditions such as limbal stem cell deficiency (LSCD)

• Patients with peripheral marginal keratitis

• Patients with history of corneal melting

• Patients with history of HSV/VZV keratitis

• Patients with history of hydrops

Related Conditions & MeSH terms

• Keratoconus

Intervention

Drug:
• Application of 0.02% MMC over 60 seconds post corneal crosslinking.
Topical application of 0.02% MMC on the surface of the cornea post CXL. The surface of the eye is washed thoroughly with Balanced Salt Solution (BSS) over 1 minute after MMC application.
• Corneal crosslinking without the application of 0.02% MMC
Topical application of placebo on the surface of the cornea post CXL. The surface of the eye is washed thoroughly with Balanced Salt Solution (BSS) over 1 minute after placebo application.

Locations

Country	Name	City	State
Canada	Hôpital Maisonneuve-Rosemont	Montréal	Quebec

Sponsors (1)

Lead Sponsor	Collaborator
Ciusss de L'Est de l'Île de Montréal

Country where clinical trial is conducted

Canada, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Corneal haze/scarring	Corneal haze or scarring will be measured by densitometry. Densitometry values obtained from Scheimpflug images (software 70722, Pentacam HR, Oculus, Germany) will inform backward light scattered reflected by the cornea and therefore reflect the amount of stromal haze, and expressed as grayscale units (GSU), defining the backscattered light in a 0 to 100 scale in concentric zones. A 6mm central zone will be used for the analysis and compartmentalized in: anterior 160 microns depth (epithelium, bowman and anterior stroma), posterior 60 microns depth (endothelium, Descemet and posterior stroma) and the layer in between.	1 month post-operation
Primary	Corneal haze/scarring	Corneal haze or scarring will be measured by densitometry. Densitometry values obtained from Scheimpflug images (software 70722, Pentacam HR, Oculus, Germany) will inform backward light scattered reflected by the cornea and therefore reflect the amount of stromal haze, and expressed as grayscale units (GSU), defining the backscattered light in a 0 to 100 scale in concentric zones. A 6mm central zone will be used for the analysis and compartmentalized in: anterior 160 microns depth (epithelium, bowman and anterior stroma), posterior 60 microns depth (endothelium, Descemet and posterior stroma) and the layer in between.	3 months post-operation
Primary	Corneal haze/scarring	Corneal haze or scarring will be measured by densitometry. Densitometry values obtained from Scheimpflug images (software 70722, Pentacam HR, Oculus, Germany) will inform backward light scattered reflected by the cornea and therefore reflect the amount of stromal haze, and expressed as grayscale units (GSU), defining the backscattered light in a 0 to 100 scale in concentric zones. A 6mm central zone will be used for the analysis and compartmentalized in: anterior 160 microns depth (epithelium, bowman and anterior stroma), posterior 60 microns depth (endothelium, Descemet and posterior stroma) and the layer in between.	6 months post-operation
Primary	Corneal haze/scarring	Corneal haze or scarring will be measured by densitometry. Densitometry values obtained from Scheimpflug images (software 70722, Pentacam HR, Oculus, Germany) will inform backward light scattered reflected by the cornea and therefore reflect the amount of stromal haze, and expressed as grayscale units (GSU), defining the backscattered light in a 0 to 100 scale in concentric zones. A 6mm central zone will be used for the analysis and compartmentalized in: anterior 160 microns depth (epithelium, bowman and anterior stroma), posterior 60 microns depth (endothelium, Descemet and posterior stroma) and the layer in between.	12 months post-operation
Primary	Corneal haze/scarring	Corneal haze or scarring will be measured by densitometry. Densitometry values obtained from Scheimpflug images (software 70722, Pentacam HR, Oculus, Germany) will inform backward light scattered reflected by the cornea and therefore reflect the amount of stromal haze, and expressed as grayscale units (GSU), defining the backscattered light in a 0 to 100 scale in concentric zones. A 6mm central zone will be used for the analysis and compartmentalized in: anterior 160 microns depth (epithelium, bowman and anterior stroma), posterior 60 microns depth (endothelium, Descemet and posterior stroma) and the layer in between.	18 months post-operation
Secondary	Clinical haze grade	Using slit lamp exam as established in the literature on a scale (the slit lamp clinical haze/scar density grade) ranging from 0 (minimum value) to 4 (maximum value); which means the higher the score, the worse the stromal haze/density is.	1 month, 3 months, 6 months, 12 months and 18 months post-operation.
Secondary	Glare	This will be measured in the treated eye and reported as the logarithm of the straylight parameter.	1 month, 3 months, 6 months, 12 months and 18 months post-operation.
Secondary	Higher-order aberrations	Higher-order aberrations (OPDScan wavefront analyzer, Gamagori, Japan) will be expressed as Zernike polynomials through the sixth order over a 6 mm diameter optical zone. HOA will allow further assessment of the optical quality of the eye.	1 month, 3 months, 6 months, 12 months and 18 months post-operation.