Abstract
Purpose :
Corneal changes are prevalent in eyes with primary congenital glaucoma (PCG). This study aimed to describe corneal irregularity and high order aberrations (HOAs) and to determine the percentages of abnormal corneal irregularity and HOAsin eyes with PCG.
Methods :
A case-control study was conducted, enrolling consecutive PCG patients with controlled intraocular pressure, as well as age-matched controls. Participants underwent corneal topography, cycloplegic refraction, best spectacle corrected visual acuity (BSCVA), and fundus photography. Corneal irregularity and HOAs were derived from topographic data and evaluated over central 4mm and 6mm diameter zones. For PCG eyes, corneal irregularity and total HOAs were categorized into normal and abnormal based on cutoffs established using 95% percentiles of controls. Optic nerve head (ONH) damage were graded using fundus photos and a grading system for childhood glaucoma. ONH grade 0 comprised eyes with a cup-to-disc ratio < 0.6.
Results :
Sixty-one eyes (39 subjects) with PCG and 61 eyes (61 subjects) of controls were enrolled.Median age of PCG participants and controls were 8.8 and 8.6 years, respectively. Irregularity and total HOAs of both 4mm- and 6mm- zones were increased in PCG eyes compared to controls (all P<0.0001). The median irregularity of PCG eyes ranged 2 to 5 times of the controls whereas the median total HOAs of the total cornea in the PCG eyes were about 2 times of the controls. As a whole, percentages of abnormal (either 4mm- or 6mm-zone) anterior corneal irregularity, posterior corneal irregularity, and total corneal HOAs were 63.9%, 86.9%, and 65.6%, respectively. Similar percentages (64.3%, 96.4%, and 67.9%) were observed among eyes with grade 0 ONH damage (n=28). In 13 eyes with grade 0 ONH damage but abnormal 4mm- total corneal HOAs, 9 (69.2%) were with BSCVA<20/25, whereas only 1 out of 7 (14.3%) were observed in eyes with normal HOAs.
Conclusions :
Abnormal corneal irregularity and HOAs are common in PCG eyes, and even in eyes with limited ONH damage. Altered corneal HOAs contributes to compromised BSCVA. Proper management of abnormal corneal changes may help promote visual outcomes of PCG patients.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.