Abstract
Purpose:
To investigate efficacy of tomography-customized corneal crosslinking and to prove hypothesis of focal weakening in primary corneal ectasia.
Methods:
In a prospective study, 22 eyes of 22 patients were treated with customized crosslinking for halting the progression of keratectasia and followed for 12 months. Standard 0.1% Riboflavin in 15% Dextran was applied for 30 min. The irradiation-profiles were centred on the maximum posterior float with energy fluencies of 10mW/cm². The total energy applied to the corneas had a maximum of 15J/cm². BSCVA, Scheimpflug imaging, topography, endothelial cell count, AS-OCT and slit lamp examination were collected as pre- and postoperative parameters.
Results:
BSCVA increased by -0.08 ± 0.16logMAR (p=0.17). No eye had a loss of more than 1 Snellen line. Kmax decreased by -0.70 ± 1.08D (p=0.11) as well as the posterior float went down by -8 ± 7µm (p=0.01). Corneal pachymetry decreased by -9 ± 11µm (p=0.05), the endothelial cell count did not change significantly (p=0.44). Average epithelium healing time was 2.63 ± 0.48 days. One eye showed sterile infiltrates, no other complications occurred.
Conclusions:
Tomography-customized corneal crosslinking is a promising approach for halting the progression of keratectasia. Due to the smaller abrasion zone necessary, customized CXL presents a less invasive procedure for the patient. For the first time a flattening of the posterior float has been observed, which may be a result of the reversal of a focal weakening of the cornea. Larger and longer study groups are needed to prove safety and validate the efficacy.