Objective: To elucidate the morphologic alterations of the cornea in atopic keratoconjunctivitis (AKC) using confocal microscopy (Heidelberg Retina Tomograph II-Rostock Cornea Module: HRT-II RCM).
Design: Prospective comparative study.
Participants: We studied 21 right eyes of 21 AKC patients (11 males, 10 females; mean age, 26.3 years) as well as 19 right eyes of 19 normal subjects (12 males, 7 females; mean age, 28.4 years).
Methods: All subjects underwent corneal sensitivity measurements, Schirmer test, tear film break-up time, fluorescein and Rose Bengal stainings, and HRT-II confocal laser scanning microscopy of the central cornea.
Main outcome measures: The epithelial and endothelial cell densities of the central cornea, the density of subbasal long nerve fibers (LNFs) and total nerve branches (NBs) of the subbasal nerve plexus were calculated. The morphologic characteristics of the corneal nerves were studied. Correlation between nerve density, tear functions, and ocular surface examination parameters were investigated.
Results: The corneal sensitivity, tear stability and vital staining scores were significantly worse in eyes with AKC (P<0.01). Eyes with AKC showed a significantly lower density of basal epithelial cells, LNFs, and NBs compared with normal eyes. Nerve fiber abnormalities such as increased tortuosity, bifurcation abnormality, sharp deflections, and thickening of stromal nerves, as well as several inflammatory cells in close proximity of the subbasal and stromal nerve fibers were observed.
Conclusions: The corneal disease in AKC was associated with significant alterations of the basal epithelium, and subbasal and stromal corneal nerves, which related to the changes in tear functions and corneal sensitivity. Confocal scanning laser microscopy was useful to study the pathological in vivo corneal changes in AKC.