Abstract
Purpose :
To evaluate the morphological changes of the corneal sub-basal nerve plexus in patients with limbal stem cell deficiency (LSCD) using in vivo laser scanning confocal microscopy (IVCM).
Methods :
A total of 101 eyes from 74 patients (mean age 61.7 ± 20.5 years) diagnosed with LSCD and 40 eyes from 34 age and gender matched normal subjects (mean age 62.9 ± 18.6 years) were included in this study. The number of eyes classified by clinical presentation as mild, moderate and severe stage were 42, 34 and 25, respectively. IVCM was performed at the central cornea. The morphology of the cells was separated into 4 categories from 0-3 with 3 being the worst. The nerves were outlined and an automatic CC Metrics software was used to measure the number of nerve fibers (FN), fiber branching (FB), fiber length (FL), and tortuosity coefficient (TC). The relationship between these nerve fiber parameters and the morphology of basal epithelial cells at the central cornea was evaluated.
Results :
Compared to control eyes, there was a reduction of FN at an average of 52%, 68% and 87% in the mild, moderate and severe stages of LSCD, respectively (P < .0001). FB decreased by 75%, 90% and 96% while FL decreased by 56%, 78% and 92% in the mild, moderate and severe stage, respectively (P < .0001). TC had a 32% reduction in moderate stage and 76% in severe stage eyes (P < .0001). The degree of reduction in all parameters of nerve fiber layers was significant among different stages of LSCD except the difference in FB and FL between the moderate and severe stages of LSCD. The cell morphology grading negatively correlated with FN (ρ=-0.650), FB (ρ=-0.682), FL (ρ=-0.679), and TC (ρ=-0.493) (all P < .0001).
Conclusions :
There are significant reductions in NF, FB and FL accompanied with an increase in nerve tortuosity in eyes with LSCD. These parameters had a negative correlation with the cell morphology grading.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.