An interventional study of Corneal collagen cross linking (CXL) and Transepithelial phototherapeutic keratectomy (t-PTK) in Keratoconus, sponsored by Oslo University Hospital. Recruiting at 1 site in Norway. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2024-02-16.
Sponsored by Oslo University Hospital · Not applicable, Interventional, and Treatment
The goal of this clinical trial is to compare CXL with combined treatment with CXL and t-PTK.
The main questions it aims to answer are whether combined treatment can give better visual acuity and if the treatments are equally safe.
313 studies on the registry are indexed under Keratoconus; 56 are open to participants now.
This study's planned enrollment of 81 is above the median of 40 across 205 interventional studies indexed under Keratoconus.
Browse Keratoconus studies →Oslo University Hospital is the lead sponsor of 834 studies on the registry; 149 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Treatment with CXL alone
Procedure: Corneal collagen cross linking (CXL)
Treatment with t-PTK combined with CXL
Procedure: Corneal collagen cross linking (CXL) · Procedure: Transepithelial phototherapeutic keratectomy (t-PTK)
Use of Avedro Inc. KXL 1 system to stop progression of keratoconus
Use Alcon Wavelight 500, excimer laser to remove the epithelium and some of the stroma over apex
Visual acuity
Uncorrected and corrected distance visual acuity in logMAR
Time frame: 1 month after surgery
Risk of progression
Change in keratometric values
Time frame: 1 year after surgery
Visual acuity
Uncorrected and corrected distance visual acuity in logMAR
Time frame: 3 month after surgery
Visual acuity
Uncorrected and corrected distance visual acuity in logMAR
Time frame: 6 month after surgery
Visual acuity
Uncorrected and corrected distance visual acuity in logMAR
Time frame: 1 year after surgery
Visual acuity
Uncorrected and corrected distance visual acuity in logMAR
Time frame: 2 years after surgery
Visual acuity
Uncorrected and corrected distance visual acuity in logMAR
Time frame: 5 years after surgery
Risk of progression
Change in keratometric values
Time frame: 1 month after surgery
Risk of progression
Change in keratometric values
Time frame: 3 months after surgery
Risk of progression
Change in keratometric values
Time frame: 6 months after surgery
Risk of progression
Change in keratometric values
Time frame: 2 years after surgery
Risk of progression
Change in keratometric values
Time frame: 5 years after surgery
Depth of demarcation line (OCT)
Measured with corneal optical coherence tomography (OCT)
Time frame: 1 month after surgery
Depth of demarcation line (confocal microscopy)
Measured with confocal microscopy
Time frame: 1 month after surgery
Patient reported outcome measure (PROMs)
National eye institute Visual Function Questionnaire 25
Time frame: 1 month after surgery
Patient reported outcome measure (PROMs)
National eye institute Visual Function Questionnaire 25
Time frame: 6 months after surgery
Patient reported outcome measure (PROMs)
National eye institute Visual Function Questionnaire 25
Time frame: 2 years after surgery
Patient reported pain after surgery
Pain the first 48 hours after the surgery graded on visual analogue scale (VAS); 0 to 10 cm.
Time frame: 48 hours after surgery
Plan to share: Undecided
No publications or documents are linked to this record.
Start is estimated for Feb 2024; primary completion for May 2025, 14 months later.
Of 59 non-industry interventional studies with no phase under Keratoconus, half reached primary completion within 34 months of starting (the median), counting those still running; a quarter within 12 and three quarters within 54. This study's planned 14 months is below that.
Counting every sponsor, half of 68 studies reached it within 34 months; a quarter within 12 and three quarters within 59.
How these figures are worked out, and which studies are left out of them.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
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