Characterization of Corneal Involvement in Eyes With Mucous Membrane Pemphigoid by in Vivo Confocal Microscopy
Purpose
To describe the morphological features of the corneal epithelial layers, sub-basal nerve plexus, stroma and endothelium in patients with mucous membrane pemphigoid (MMP) by using in vivo confocal microscopy (IVCM).
Methods
Central cornea images were prospectively captured from 15 healthy control eyes and 24 eyes with clinically diagnosed mucous membrane pemphigoid using In Vivo Laser Scanning Confocal Microscopy (HRT III RCM). Morphological changes of the corneal epithelial layers, stroma, endothelium as well as characteristics of corneal nerves and presence of inflammatory dendritic cells (DCs) were evaluated.
Results
Images obtained by IVCM from 39 eyes were analyzed. As compared to controls, end stage MMP affected eyes displayed severe conjunctivalization of the cornea, with limited identifiable cellular or structural elements: conjunctival cells, leukocyte infiltration, neovascularization and scarring. Non-severe MMP affected eyes showed metaplasia of the corneal epithelial layers, presence of hyper-reflective cells similar to conjunctival cells, corneal defects, opacification of anterior stroma and hyper-reflective endothelial deposits. Images of the sub-basal nerve plexus demonstrate significant reduction in density (1251.3±806.9 µm/frame vs. 3434.7±516.63 µm/frame, p<0.001) and increased density of DCs (115±88 cells/mm2 vs. 30.22±11.42 cells/mm2,p<0.05).
Conclusion
IVCM reveals profound and variable microstructural changes in the corneas of patients with ocular manifestations of MMP as compared to normal corneas. Our study demonstrated decreased corneal nerve density and elevated dendritic cells density in non-severe MMP affected eyes, as compared to normal controls. All these findings suggest implications for the use of IVCM in the evaluation and monitoring of patients with MMP.