Changes of corneal densitometry in patients with keratoconus after corneal collagen cross-linking

Abstract

AIM: To observe the changes of corneal densitometry(CD)in patients with keratoconus after corneal cross-linking(CXL).METHODS: Retrospective study. A total of 32 patients(43 eyes)with keratoconus in Ningxia Eye Hospital from April 2020 to April 2022 were selected. Pentacam analysis system divided the cornea into three layers: anterior 120 μm, middle layer and posterior 60 μm, and divides it into five regions with diameters of 0-2, 2-6, 6-10, 10-12 mm and full diameter according to the diameter, and measures the CD in different ranges. The changes of CD were compared before operation and at 1, 3 and 6 mo after operation.RESULTS: There were differences in uncorrected visual acuity, best corrected visual acuity and intraocular pressure before and 6 mo after operation(all P<0.05), and there was no difference in corneal endothelial cells(P=0.477). CD reached its peak at 1 mo after operation, and decreased at 3 mo and 6 mo after operation, but it was still higher than that before operation. There is a significant positive correlation between CD and Kmax in the anterior layer and the whole layer(r=0.164, P=0.016; r=0.152, P=0.023).CONCLUSION: The values of CD peaked at 1 mo after CXL, then it gradually decreased, tending to become stable at 6 mo postoperatively.

Keywords

• keratoconus
• corneal cross-linking
• corneal densitometry