Purpose
Partial thickness corneal opacities are amenable to anterior lamellar keratoplasty. This technique may provide an alternative to penetrating keratoplasty in children which is standard of care in this age group and ameliorate some of the well-known technical difficulties (posterior pressure, scleral plasticity, phakic status) and vision-threatening post-operative complications (infection, glaucoma) that are well-described in this age group. The purpose of this study is to describe a novel technique using anterior segment OCT to design custom femptosecond-trephenated corneal donor tissue in a zig-zag pattern to dove-tail into an excimer laser-ablated host corneal bed.
Methods
Children ages1 month-18 years of age with partial thickness corneal opacities without exclusion criteria (glaucoma, anterior segment anomalies, an eye condition other than corneal opacity that decreases visual prognosis) were enrolled in the study. Each subject is imaged with anterior segment OCT (iVue) and the depth of the opacity is measured. A custom designed femptosecond-trephinated corneal donor button is prepared in the zigzag pattern. The host cornea is ablated with an excimer laser (VISX S4) according to pachymetry measurements obtained from the OCT and actively guided with intraoperative ultrasonic pachymetry. A minimum posterior lamellar depth of 150 μm is maintained. The donor button is sutured in with standard 16-bite radially placed, interrupted, 10-0 nylon sutures. Pre, intra, and post op OCT images are obtained.
Results
One child with a partial thickness corneal opacity underwent the procecure. Pre-operative external photos and anterior segment OCT images of pre and post OCT-guided LALak are presented. (Figures 1 and 2).
Conclusions
Laser-assisted Anterior Lamellar Keratoplasty (LALaK) is a novel technique that can provide an alternative to standard penetrating keratoplasty in children with partial thickness corneal opacities.
Keywords: 479 cornea: clinical science •
741 transplantation •
578 laser