Corneal thickness recovers after CXL

After a corneal collagen cross-linking (CXL) procedure a patient's cornea thins but then recovers towards original thickness, according to a one-year follow-up study published in the Journals of Cataract and Refractive Surgery.

Dr Peter S. Hersh et al., Cornea and Laser Eye Institute, New Jersey, USA, studied 54 eyes with keratoconus and 28 eyes with ecstasia after LASIK. The outcome measures were corneal thickness at the apex, the thinnest point and the pupil centre. These were measured at baseline and 1, 3, 6 and 12 months post-CXL.

Mean preoperative thinnest pachymetry was 440.7 μm ± 52.9 SD. Apex and corneal thickness returned to baseline after 1 year. Corneal thickness recovered more rapidly in ecstasia patients than in keratoconus patients. Although the researchers found that the corneal thickness was reduced up to 3-months post-op, the baseline thickness was recovered at 3 to 6-months follow-up.

In conclusion, the baseline thickness of the cornea is recovered after CXL but the causes and possible effects of this change in thickness still need to be explained.