Corneal collagen cross-linking in keratoconus: primum non nocere

What are the costs, capacity, and clinical implications of ‘waiting for documented progression’ in young West of Scotland patients prior to collagen cross linking?

“…Early intervention with CXL at first presentation remains controversial, as the procedure carries the potential for complications that may result in reduction in vision. These include development of corneal stromal haze, microbial keratitis, scar formation, and failure of treatment resulting in continued ectasia progression [ 13 , 14 ]. In our cohort, two eyes out of 56 (3.6%) developed keratitis following CXL.…”

“…The average duration between initial presentation and CXL treatment was over 1 year in our cohort, and we also identified significant time delays between time of listing to delivery of treatment, which is a further source of unrecognised progression. Variability in, or unreliable, topographic readings can also delay detecting progressive disease, which increases the risk of ‘silent’ progression during monitoring and can influence the decision to treat [ 13 , 15 , 16 ].…”

“…If all 56 eyes requiring CXL were treated at first presentation without monitoring for progression, 140 consultations would have been avoided in this cohort, with a conservative potential cost saving of £18,900 (clinic appointment cost £135; local NHSGGC estimate). However, this policy would have resulted in 28 potentially unnecessary CXL procedures (and exposure to the 3% risk of complications) if our whole cohort had their first/worse eye treated at presentation [ 13 ]. We have shown that young patients who progress have more extreme topography at presentation.…”