Fig. 3From: Long term results of accelerated 9 mW corneal crosslinking for early progressive keratoconus: the Siena Eye-Cross Study 2The baseline and follow-up measurements of Kmax showed that it improved significantly at 6th postoperative month, from 55.7 D to 54.36 D (P = 0.03) and remained statistically significant up to the 5th year of follow-up (P = 0.001) with a delta of − 1.49 DBack to article page