PRICS: Corneal Crosslinking Treatment Study
Study Details
Study Description
Brief Summary
Three different protocols for inducing corneal crosslinks in subjets with progressive keratoconus will be evaluated in this randomised clinical study.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
Phase 4 |
Detailed Description
Riboflavin does not penetrate the intact corneal epithelium. CXL is typically performed using the so-called "Dresden protocol". The Dresden protocol states 30 minutes of UVA-radiation (3mW/cm2) but a 10 minute irradiation protocol (9mW/cm2) is frequently used. Both of the protocols involve mechanical removal of the epithelium over the central 8 mm of the corneal surface. The first days after treatment therefore involves some degree of pain, often intense, and the presence of a healing epithelial defect may be associated with development of infiltrates in the cornea. A number of approaches have been evaluated in order to promote riboflavin penetration through the intact epithelium, of which iontophoresis appears most promising. Keratoconic corneas are thin at the cone location and sometimes it is difficult to maintain the safety margin of 400 microns during corneal crosslinking. Instead of using isotonic standard riboflavin, a swelling effect of the cornea can be obtained by using hypotonic riboflavin. However, the latter has been indicated as less effective in the process of inducing cross links.
Ninety eyes of 90 patients of various degrees of keratoconus will be randomised to one of the following groups: 1) CXL (UVA 9mW/cm2) using isotonic riboflavin, or 2) CXL (UVA 9mW/cm2) using hypotonic riboflavin or 3) Iontophoresis with Ricrolin with following CXL (UVA 9mW/cm2).
Hypothesis:
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CXL with hypotonic riboflavin or CXL with Ricrolin administered by iontophoresis or CXL with isotonic riboflavin is non-inferior compared to standard CXL with isotonic riboflavin.
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The morphological structure post-CXL in the three different groups will be similar without any significant differences.
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Active Comparator: Isotonic riboflavin CXL (UVA 9mW/cm2) treatment using isotonic riboflavin |
Procedure: Corneal crosslinking: CXL (UVA 9mW/cm2)
CXL treatment with UVA-radiation (9mW/cm2) with a 10 minute irradiation protocol.
Drug: Isotonic riboflavin
CXL protocol with isotonic riboflavin
|
| Active Comparator: Hypotonic riboflavin CXL (UVA 9mW/cm2) using hypotonic riboflavin |
Procedure: Corneal crosslinking: CXL (UVA 9mW/cm2)
CXL treatment with UVA-radiation (9mW/cm2) with a 10 minute irradiation protocol.
Drug: Hypotonic riboflavin
CXL protocol with hypotonic riboflavin
|
| Active Comparator: Iontophoresis Iontophoresis with Ricrolin with following CXL (UVA 9mW/cm2). |
Procedure: Corneal crosslinking: CXL (UVA 9mW/cm2)
CXL treatment with UVA-radiation (9mW/cm2) with a 10 minute irradiation protocol.
Procedure: Iontophoresis
CXL protocol with iontophoresis and ricrolin
|
Outcome Measures
Primary Outcome Measures
- Postoperative change in visual acuity [Patients will be evaluated 1, 6, 12 and 24 months after treatment.]
Uncorrected visual acuity (UCVA) and best spectacle corrected visual acuity (BSCVA)
- Postoperative change in Kmax [Patients will be evaluated 1, 6, 12 and 24 months after treatment.]
Maximum corneal steepness
Secondary Outcome Measures
- Postoperative change in astigmatism [Patients will be evaluated 1, 6, 12 and 24 months after treatment.]
Corneal astigmatism
- postoperative change in corneal nerve cell density [Confocal microscopy will be performed at 6 and 12 months.]
Corneal nerve cell density will be evaluated using confocal microscopy
- Postoperative change in Keratocyte cell density [Confocal microscopy will be performed at 6 and 12 months.]
Keratocyte cell density will be evaluated using confocal microscopy
- Postoperative change in endothelial cell count [Confocal microscopy will be performed at 6 and 12 months.]
Endothelial cell count will be evaluated using confocal microscopy
- Postoperative change in demarcation lines [Confocal microscopy will be performed at 6 and 12 months.]
Identification of the demarcation lines with confocal microscopy will help establishing how deep was the effect of the CXL treatment.
- Postoperative change in the corneal thickness during CXL treatment [Corneal pachymetry will be evaluated before and then every 5 minutes during 30 minutes under CXL treatment.]
Corneal pachymetry is the process of measuring the thickness of the cornea
Eligibility Criteria
Criteria
Inclusion Criteria:
- Progress in keratoconic eye. We define progress as an increase in Kmax of 1.0 diopter in 1 year or 0.5 diopter in 6 months. This increase in Kmax will be accepted as progression if concomitant changes tomographic parameters.
Exclusion Criteria:
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Concurrent ocular infection or corneal disease other than keratoconus.
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Pregnancy.
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Treatment with Isotretinoin.
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | Skåne University Hospital | Lund | Skåne | Sweden | 22242 |
Sponsors and Collaborators
- Region Skane
Investigators
- Principal Investigator: Ingemar Gustafsson, MD, Region Skåne
Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- DNR2015/373