Confocal microscopy of Thygeson's superficial punctate keratopathy

Purpose. To describe the changes seen with the confocal microscope in Thygeson's superficial punctate keratopathy (TSPK). Methods. Confocal microscopy was performed on six patients with TSPK presenting to Manchester Royal Eye Hospital from October 1999 to June 2001. Both eyes were examined including the normal fellow eyes of two patients with unilateral TSPK. Images were compared with age-matched controls. Results. Irregular nerve fibers, masked by considerable haze, were seen in the subepithelial nerve plexus immediately above Bowman's membrane in TSPK. Generalized haze was also present in the anterior stroma along with areas of high reflectivity, microdots, and reflective bodies. Keratocytes had highly reflective nuclei and cell bodies of irregular size, orientation, and shape. The changes were related to the duration of TSPK, were not seen in normal fellow eyes, and were also present in areas without lesions. Conclusion. Confocal imaging of TSPK demonstrated considerable abnormalities in the subepithelial nerve plexus, Bowman's membrane, and the anterior stroma that were related to disease duration. Similar changes have been reported in a variety of corneal diseases and following laser corneal surgery. Recent evidence has supported interactions between the epithelium and Bowman's membrane and the anterior stroma in corneal disease and after laser corneal surgery. We speculate that such interactions may have a role in TSPK.