Short-Term Effect of Conventional Versus Accelerated Corneal Cross-Linking Protocol on Corneal Geography and Stability

: To determine the 6-month effect of conventional (CXL30) and accelerated cross-linking with a UVA intensity of 9 mW/cm (CXL10) on corneal stability and to investigate whether there was a difference in ABCD grading system parameters regarding the two different procedures. : Twenty-eight eyes of 28 patients with a documented keratoconus (KN) progression were included. Patients were selected to undergo either epi off CXL30 or CXL10. At the baseline and the follow-up visits after one (V1), three (V2), and six months (V3), the patients underwent complete ophthalmic examination and corneal tomography. : In the CXL30 group, all the parameters from the ABCD grading system significantly changed from baseline to V3; parameter A decreased ( = 0.048), B and C increased ( = 0.010, < 0.001), and D decreased ( < 0.001). In the CXL10 group, there were no changes in parameters A ( = 0.247) and B ( = 0.933), though parameter C increased ( = 0.001) and D decreased ( < 0.001). After an initial decline after one month, visual acuity (VA) recovered on V2 and V3 ( < 0.001), and median maximal keratometry (Kmax) decreased in both groups ( = 0.001, = 0.035). In the CXL30 group, there were significant changes in other parameters; average pachymetric progression index ( < 0.001), Ambrósio relational thickness maximum (ARTmax) ( = 0.008), front and back mean keratometry ( < 0.001), pachymetry apex (PA) ( < 0.001), and front elevation ( = 0.042). However, in the CXL10 group, there were significant changes only in ARTmax ( = 0.019) and PA ( < 0.001). : Both epi-off CXL protocols showed similar short-term efficacy in improving VA and Kmax, halting the progression of KN, and both similarly changed tomographic parameters. However, the conventional protocol modified the cornea more significantly.