Due to copyright issues, an electronic copy of the thesis must be ordered from the faculty. For the faculty to have time to process the order, the order must be received by the faculty at the latest 2 days before the public defence. Orders received later than 2 days before the defence will not be processed. After the public defence, please address any inquiries regarding the thesis to the candidate.
Trial Lecture – time and place
See Trial Lecture.
Adjudication committee
- First opponent: Professor Anders Behndig, Umeå University, Sweden
- Second opponent: Clinical Associate Professor Anders Ramløv Ivarsen, Aarhus University, Denmark
- Third member and chair of the evaluation committee: Professor Emeritus Borghild Barth-Heyerdahl Roald, University of Oslo
Chair of the Defence
Professor Emeritus Emilia Kerty, University of Oslo
Principal Supervisor
Professor Liv Kari Drolsum, University of Oslo
Summary
Keratoconus is a condition in which the connective tissue in the cornea gradually weakens and causes it to develop a cone shape which, without glasses or contact lenses, causes reduced vision. The condition is more common than previously thought, with a prevalence of up to 0.27%. If left untreated, keratoconus can lead to advanced disease and a scarred cornea, requiring a corneal transplantation to improve vision. However, there are several risk factors associated with this procedure both during and after the operation.
Corneal collagen cross-linking (CXL) is a treatment that can halt progression of the disease. It involves the use of riboflavin drops and ultraviolet A (UVA) irradiation to stiffen the cornea.
The aim of this thesis was to compare the efficacy and structural changes of CXL using conventional and accelerated UVA irradiation, as well as two different riboflavin solutions in a prospective randomized case series. In addition, by collecting data from the corneal transplant registry at the Department of Ophthalmology at Oslo University Hospital, the thesis examines the extent to which a 15 year implementation period of CXL treatment has affected the rate of corneal transplantation in patients with keratoconus.
The findings reveal that CXL with both conventional and accelerated UVA irradiation shows comparable clinical results when using riboflavin with hydroxypropyl methylcellulose. However, it also identifies deeper than expected structural changes in the corneas, particularly with the use of CXL with conventional UVA irradiation, suggesting caution when using this riboflavin solution. Additionally, the thesis has shown a significant decrease in the number of corneal transplantations over 15 years, potentially attributed to the implementation of CXL.
Overall the findings support the need to offer CXL to all patients with progressive keratoconus and advocate for the use of CXL accelerated UVA irradiation using riboflavin with hydroxypropyl methylcellulose.
Additional information
Contact the research support staff.