Abstract
Purpose :
To elucidate the influence of Langerhans cells on the objective analysis of corneal subbasal nerve morphology and investigate its clinical significance in contact lens associated dry eye.
Methods :
Firstly, 931 IVCM images containing corneal subbasal nerves and Langerhans cells (LCs) were selected in the database of our department. Segmentation of corneal nerves and LCs were performed by An Infinite Perimeter Active Contour with Hybrid Region Information (IPACHI) model combining Deformable and External Attention Module (DEAM). Then corneal nerve parameters including Corneal Nerve Fiber Length (CNFL), Corneal Nerve Branch Density (CNBD), Corneal Nerve Tortuosity, and Boxdim were calculated, as well as the number of LCs. Then a cross sectional study recruiting healthy volunteers, non-contact lens associated dry eye (NCLADE) and contact lens associated dry eye (CLADE) was carried out, evaluating their ocular surface symptoms and signs, including OSDI, TBUT, Schirmer’s I test, and CFS scores, and exploring the clinical significance of the corneal subbasal nerve morphological parameters and LCs in above subjects.
Results :
The corneal nerves and LCs were successfully segmented separately. After exclusion of LCs, CNFL, CNBD and Boxdim of corneal nerves were significantly decreased. However, Corneal Nerve Tortuosity was increased. Further results showed that the difference of CNFL, CNBD and Boxdim between corneal nerves with LCs and without LCs were positively correlated with the number of LCs. However, the difference of Corneal Nerve Tortuosity was negatively correlated with the number of LCs (Figure 1). CNFL, CBND and Boxdim were little correlated with TBUT and CFS scores after removal of LCs. Meanwhile, TBUT and CFS scores were significantly correlated with the number of LCs (Figure 2).
Conclusions :
Objective analysis of corneal nerve morphology is significantly influenced by Langerhans cells, causing increased CNFL, CNBD, Boxdim, and decreased Tortuosity. LCs may introduce a false-positive possibility in clinical correlations of corneal nerve parameters in NCLADE and CLADE. LCs likely contribute to corneal epithelial damage, evidenced by the strong relationship between LC numbers and CFS scores.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.