The Additional Role of Supplemental Oxygen Therapy in Accelerated Corneal Collagen Cross-linking in Progressive Keratoconus. A Randomized Clinical Trial

Phase 2

• Conditions: Keratoconus
• Interventions: Procedure: perform corneal collagen cross linking accelerated and delivery of systemic oxygen; Procedure: perform Conventiona corneal collagen cross linking; Procedure: perform corneal collagen cross linking accelerated and without additional oxygen therapy

• Registration Number: NCT04343326
• Lead Sponsor: Shahid Beheshti University of Medical Sciences

Brief Summary

It is aimed to investigate the role of supplemental systemic oxygen therapy during accelerated corneal collagen crosslinking (CXL).

In this prospective randomized clinical trial, patients with progressive keratoconus who are candidates for receiving CXL will be included. The patients will be randomized and allocated to three different CXL protocol. In the first group (OA-CXL), CXL is performed using an accelerated protocol (9 mW/ CM2 for 10 minutes) in addition to the delivery of systemic oxygen with a rate of 5 liters/min through a nasal mask for 10 minutes during UV-A ablation. Patients in the second group (A-CXL) will receive CXL with the same accelerated protocol without additional oxygen therapy. Conventional CXL using 30 mW/CM2 UV-A ablation for 30 minutes is perfomed in the patients of the third goup (C-CXL). Maximum keratometry in Sirius corneal tomography as the primary outcome and uncorrected and corrected distance visual acuity (UDVA, CDVA) and corneal biomechanical properties including corneal resistance factor (CRF) and corneal hysteresis (CH) as secondary outcome measures are followed for a six- and 12-months period. A P-value of less than 0.05 is considered as statistically significance level.

Detailed Description

Not available

Study Timeline

• Study Start: 2020-01-01
• Status Verified: 2020-04
• Study First Submitted: 2020-04-09
• Study First Submitted QC: 2020-04-09
• Last Update Submitted: 2020-04-09
• Study First Posted: 2020-04-13
• Last Update Posted: 2020-04-13
• Primary Completion: 2020-05-01
• Study Completion: 2020-06-01

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 30

Inclusion Criteria

• definitive diagnosis of progressive keratoconus for whom CXL is indicated were enrolled in this study
• The indication is identified by a cornea specialist and was considered as follows.
• Patients with the definitive diagnosis of KC who aged 18 or more were considered for the procedure if they had an increase of 1 D in Kmax or an increase of 1D in the manifest cylinder over the past 12 months.

Exclusion Criteria

• patients with the previous history of corneal surgery
• corneal scar or pathologies like herpetic eye disease or severe dry eye
• corneal thickness less than 400 micrometers
• pregnant or nursing women
• corneal Kmax more than 60
• age over 35 years
• severe ocular surface disease

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
accelerated corneal cross linking+ delivery of systemic oxygen	perform corneal collagen cross linking accelerated and delivery of systemic oxygen	corneal cross linking is performed using an accelerated protocol (9 mW/ CM2 for 10 minutes) in addition to the delivery of systemic oxygen with a rate of 5 liters/min through a nasal mask for 10 minutes during UV-A ablation
conventional corneal collagen cross-linking	perform Conventiona corneal collagen cross linking	Conventional corneal cross linking using 30 mW/CM2 UV-A ablation for 30 minutes
accelerated corneal collagen cross-linking	perform corneal collagen cross linking accelerated and without additional oxygen therapy	corneal cross linking with the same accelerated protocol without additional oxygen therapy.

Primary Outcome Measures

Name	Time	Method
Postoperative refractive error	12 months	Sirius and ocular response analyzer

Secondary Outcome Measures

Name	Time	Method
Ocular biomechanics	6 months	Ocular response analyzer

Trial Locations

Locations (1)

Ophthalmic Research Center; 🇮🇷 Tehran, Iran, Islamic Republic of