Atypical Presentation of Salzmann Nodular Corneal Degeneration as a Subepithelial Corneal Dystrophy: A Case Report

Abstract

Salzmann nodular corneal degeneration (SNCD) is a rare, non-inflammatory, slowly progressive degenerative disease of the cornea. It is characterized by bluish-white nodules raised above the surface of the cornea. SNCD does not seem to consist of one clinical entity, which poses challenges to differentiate it from corneal dystrophies. A 20-year-old Chinese female with a history of eczema and dry eyes presented with a complaint of itchiness in both eyes, watery eyes, and gradual blurring of vision in the right eye for two years. Upon examination, right eye vision was counting fingers, whereas the left eye's best-corrected vision was 6/9. The anterior segment examination of the right eye showed generalized cornea haziness with superficial vascularization, while the left eye showed mild corneal haziness with no vascularization. Otherwise, both eyes had no signs of corneal infection, corneal scar, subepithelial nodular appearance, or allergic reactions, with no evidence of fluorescein staining. Anterior segment optical coherence tomography (AS-OCT) did not indicate subepithelial opacity. Subsequently, the patient underwent right eye superficial keratectomy under local anesthesia. Although clinically the patient was thought to have a form of subepithelial dystrophy, the histopathological report confirmed it to be SNCD. The best-corrected vision of the right eye improved to 6/12 post-keratectomy. We report an unusual presentation of Salzmann's corneal degeneration as subepithelial corneal haziness, which was treated successfully with superficial keratectomy.

Keywords: degenerative disease; dry eye; salzmann nodular degeneration; subepithelial corneal dystrophy; superficial keratectomy.

Figure 1. Pre-operative anterior segment photo and AS-OCT of the right eye

AS-OCT, anterior segment optical coherence tomography

Figure 2. Photo of the anterior segment of the left eye

Figure 3. Post-operative anterior segment photo and AS-OCT of the right eye

AS-OCT, anterior segment optical coherence tomography

Figure 4. Histology slide of the debrided cornea of the patient with thickened corneal stroma, which contained deposition of hyalinized material.