PURPOSE: To evaluate the changes in corneal transparency
and thickness measured objectively using Pentacam
Scheimpfl ug (Oculus Optikgerate GmbH) corneal
tomography (densitometry) after corneal cross-linking
(CXL).
METHODS: Twenty-two eyes from 15 patients with
keratoconus underwent CXL. Corneal thickness and curvature
as well as lens and corneal densitometry were
measured at baseline and 1, 3, 6, and 12 months after
CXL with Pentacam.
RESULTS: Immediately after CXL, central corneal thickness
signifi cantly decreased (240 ƒÊm) and corneal
densitometry increased signifi cantly. At 6-month followup,
densitometry values were reduced and seemed to
stabilize at a higher value than baseline. No statistically
signifi cant differences were noted (mean difference at
12 months: 130%). Changes in corneal densitometry
were detected with the Pentacam even when clinical
haze did not increase beyond grade 1 during follow-up.
CONCLUSIONS: Corneal CXL is associated with a transient
reduction in central corneal thickness, which recovered
to baseline after 12 months. During the same
time period, corneal densitometry experienced a transient
increase that recovered to baseline values after 3
months. Changes in compactness of the corneal tissue
after CXL may have an impact in corneal power not due
to curvature changes, but to refractive index changes
as a result of hydration changes. Pentacam is a useful
objective method to monitor corneal transparency after
CXL.This study was supported in part by a grant from the Spanish Ministry of Health, Instituto Carlos III, Red Tematica de Investigacion Cooperativa en Salud "Patologia ocular del envejecimiento, calidad visual y calidad de vida," Subproyecto de Calidad Visual (RD07/0062
