In vivo laser scanning confocal microscopy of vernal keratoconjunctivitis

P>Background: To demonstrate the morphological characteristics of vernal keratoconjunctivitis (VKC) by using in vivo laser scanning confocal microscope (LSCM). Design: Descriptive analysis of VKC by LSCM performed in EENT Hospital of Fudan University. Participants: 26 patients diagnosed as VKC and 26 age-matched healthy controls were enrolled in the study. Methods: The HRTII/RCM was used to examine bulbar conjunctiva, tarsal conjunctiva, superior limbus and inferior limbus. Main Outcome Measures: The density of Langerhans cells and inflammatory cells in tarsal and bulbar conjunctiva were calculated. The morphology of Vogt Palisades was analysed and normal rate of Vogt Palisades at superior and inferior limbus was calculated, respectively. Results: Infiltration of a larger number of Langerhans cells and inflammatory cells could be identified in both bulbar conjunctiva and tarsal conjunctiva compared with normal subjects. Furthermore, the density of Langerhans cells in tarsal conjunctiva was significantly higher in tarsal form and mix form than that in bulbar form (P = 0.048). Normal Vogt Palisades were visible only in 15 and 23 eyes at superior and inferior limbus respectively. Abnormal Vogt Palisades were characterized by atrophy or absence of stromal papillae and disappearance of bright basal cells, accompanied with the infiltration of more Langerhans cells. At superior limbal area, bulbar form had the highest abnormal rate, followed by mix form, both were significantly higher than tarsal form (P = 0.005). Conclusions: The in vivo morphological characteristics of conjunctiva and limbus in VKC included the infiltration of Langerhans cells and inflammatory cells in epithelium and stroma, and the destruction of Vogt Palisades.