In Vivo Confocal Microscopic Changes of the Corneal Epithelium and Stroma in Patients With Herpes Zoster Ophthalmicus

PurposeTo analyze the density and morphology of corneal epithelial cells and keratocytes by in vivo confocal microscopy (IVCM) in patients with herpes zoster ophthalmicus (HZO) as associated with corneal innervation.DesignProspective, controlled and masked cross-sectional study.Methodssetting: Single-center study. patients: Thirty eyes with the diagnosis HZO and their contralateral clinically unaffected eyes, 15 eyes of 15 normal controls. intervention procedures: In vivo confocal microscopy and corneal esthesiometry of the central cornea. main outcome measures: Changes in morphology and density of the superficial and basal epithelial cells and stromal keratocytes, and correlation with corneal sensation.ResultsThe density of superficial epithelial cells in HZO eyes with severe sensation loss (766.5 ± 25.2 cells/mm2) was significantly lower than both healthy control eyes (1450.23 ± 150.83 cells/mm2) and contralateral unaffected eyes (1974.13 ± 298.24 cells/mm2) (P = .003). Superficial epithelial cell size (1162.5 μm2) was significantly larger in HZO eyes with severe loss of sensation, as compared to contralateral (441.46 ± 298.14) or healthy eyes (407.4 ± 47.2μm2; all P < .05). The density of basal epithelial cells, anterior keratocytes, and posterior keratocytes did not show statistical significance between patients, controls, and contralateral unaffected eyes. Changes in superficial epithelial cell density and morphology correlated strongly with corneal sensation.ConclusionsIn vivo confocal microscopy reveals profound HZO-induced changes in the superficial epithelium, as demonstrated by increase in cell size, decrease in cell density, and squamous metaplasia. We demonstrate that these changes strongly correlate with changes in corneal innervation in eyes affected by HZO.