To report 2 cases of far-advanced keratoconus with a high value of maximum keratometry and very thin corneas treated with corneal crosslinking (CXL).

The thinnest corneal thickness of an 18-year-old woman with maximum keratometry of 106.5 D (case 1) was 335 µm. The thinnest corneal thickness of a 43-year-old man with maximum keratometry of 120.3 D (case 2) was 345 µm. The two cases underwent a customized topography and pachymetry-guided epithelial debridement technique to preserve the epithelium where the cornea was within 2 mm around the cone and subsequent CXL. Postoperative maximum keratometry was 97.2 D 24 months after CXL in case 1 and 109.3 D 18 months after CXL in case 2. Postoperatively, the thinnest corneal thickness was 343 µm in case 1 and 162 µm in case 2. The corneal thickness in case 1 was stabilized during the follow-up examination. The pupil center and apex of the corneal thickness in case 2 with the higher maximum keratometry was stabilized, but the thinnest corneal thickness was decreased immediately after CXL and did not recover before CXL.

CXL was performed in 2 cases of far-advanced keratoconus. Results showed reduced maximum keratometry but, variable values in corneal thickness during the follow-up examination in the 2 cases. Longer follow-up is necessary, and CXL should be performed cautiously, especially for patients with far-advanced keratoconus.