Examination of corneal microstructure in the quiescent phase of vernal keratoconjunctivitis using in vivo confocal microscopy.

ABSTRACT

INTRODUCTION: This study investigated the morphological characteristics of corneal microstructure in the quiescent phase of vernal keratoconjunctivitis (VKC). METHODS: Twenty patients with quiescent VKC and 25 healthy subjects were included. In vivo confocal microscopy (IVCM) of the central cornea was performed. Cellular density of each layer and the morphology of subbasal nerve plexus (SBNP) was analysed. Langerhans cell density (LCD), morphology (LCM), and field area (LCF) were also examined. RESULTS: No differences were found either in cell densities nor in SBNP morphology (p > 0.05). LCD, LCM and LCF were significantly higher in the VKC group (p = 0.005, p < 0.001 and p < 0.001, respectively). The severity of papillary hypertrophy had a significant impact on LCD, LCM and LCF (ß-coefficient 19.541, p < 0.001; ß-coefficient 0.283, p < 0.001 and ß-coefficient 595.255, p < 0.001, respectively). DISCUSSION: In quiescent VKC, LCD, LCM, and LCF were increased, and they were associated with the severity of papillary hypertrophy. Alterations of Langerhans cells indicate a subclinical inflammatory process without ocular symptoms.