Abstract
Purpose :
To create a clinical score system to classify the severity of limbal stem cell deficiency (LSCD) based on the extent of corneal and limbal involvement, best-corrected visual acuity (BCVA) and central cornea basal epithelial cell density (BCD).
Methods :
This is a retrospective observational comparative study. A total of 48 eyes of 34 patients with LSCD and 10 eyes of 8 normal subjects as control were included. Confocal images of the central cornea using the Heidelberg Retina Tomograph III Rostock Cornea Module were collected. Two independent observers measured BCD. Clinical presentation including BCVA and ocular surface involvement was reviewed. A clinical grading score was created based on three clinical findings of the extent and location of surface involvement. A score of 1 to 4 was assigned based on the clock hours of the limbus affected and on the number of cornea areas involved. A score of 2 was assigned if the central visual axis was involved. LSCD was classified in mild, moderate and severe stage based on the total clinical score of ≤4, ≥5 to ≤7, and ≥8 to 10, respectively. Statistical analysis was performed to investigate potential correlation between clinical score, BCVA and BCD.
Results :
There were 18 eyes (38%) in mild, 17 eyes (35%) in moderate and 13 eyes (27%) in severe stage. The BCD decreased 23.1% in mild, 40.5% in moderate and 65.5% in severe stage compared to that in the control (p<0.002). The BCD significantly decreased with a larger clock hours affected, a greater portion of the cornea surface involved and when the central visual axis was affected (all p<0.05). There was a significant greater decrease of BCD if the inferior, nasal or temporal quadrant was affected (all p<0.05). The mean BCVA LogMAR was 0.0±0.0 in control, 0.2±0.5 in mild, 0.6±0.4 in moderate and 1.6±1.1 in severe stage (p<0.0001). There was a positive correlation between a higher total score and BCVA LogMAR (rho 0.75; p<0.0001). A higher clinical severity score strongly correlates with a decrease of central corneal BCD (rho 0.61; p<0.0001).
Conclusions :
Central cornea BCD positively correlates with the extent of clinical involvement. This new clinical score system could be used to classify the severity of LSCD.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.