In Vivo Confocal Microscopy in Terrien Marginal Corneal Degeneration: A Case Report

Abstract
To report an advanced case of Terrien marginal corneal degeneration (TMD) analyzed by means of confocal microscopy. A 62-year-old woman with TMD underwent a routine ophthalmological examination and was evaluated for the disease by using in vivo laser scanning confocal microscopy with the Heidelberg Retina Tomograph 2 Rostock Cornea Module. The slit-lamp examination of the right eye showed an upper peripheral cornea thinning associated with a deposition of refractile yellow-white materials in the anterior stroma. Superficial radial vessels in the upper peripheral cornea were the only pathological findings of the left eye. Confocal microscopy of the right eye lesion showed deposition of hyperreflective material, and the stroma below presented a honeycomb-like pattern. Inflammatory cell infiltration, abnormal subbasal nerve plexus, epithelial basal membrane defects, irregular Bowman membrane, and the presence of activated keratocytes were observed in the cornea of both eyes. In vivo confocal microscopy can detect subtle corneal changes in an advanced case of TMD, which may be signs of subclinical inflammation.