Title: Ultra High-Resolution Oct In Diagnosing Salzman Nodular Degeneration And Peripheral Hypertrophic Subepithelial Fibrosis

Corneal epithelial degenerations encompass a spectrum of disorders characterized by abnormal cellular and structural changes in the corneal epithealium, posing challenges to accurate diagnosis and characterization. Optical Coherence Tomography (OCT) has been a valuable imaging modality, providing detailed insights into corneal morphology. However, conventional OCT may fall short of capturing subtle alterations associated with specific subtypes of corneal dystrophies. This study explores the utility of  Optical Coherence Tomography (HR-OCT) in evaluating various subtypes of corneal epithelial dystrophy, focusing on detecting subtle changes not discernible through conventional OCT.

A prospective, cross-sectional study involving 18 eyes was conducted using the High-Resolution (HR) Revo OCT (Optopol Technology Zawiercie, Poland). HR Revo is capable of capturing 130k/A scans per second with an axial resolution of 3 µm and a digital resolution of 1.6 µm. Among the eyes examined, 10 had Salzman Nodular Degnerations, and 7 had peripheral hypertrophic subepithelial corneal degeneration. 

Measurements were performed using the HR Revo OCT. The study included a diverse sample of 17 eyes with two different subtypes of corneal degeneration. Specifically, we investigate Peripheral Hypertrophic Subepithelial Corneal and Salzman Nodular Degeneration using a High-Resolution Revo. The research utilized HR-OCT to capture detailed images and identify nuanced changes in the corneal structure that may go unnoticed with conventional OCT imaging. All participants had an in-vivo corneal confocal microscopy that confirmed the diagnosis.

On HR-OCT imaging, peripheral hypertrophic subepithelial corneal degeneration presented with sharply demarcated hyperreflective flatter fibrosis localized above the basement membrane leading to epithelial thinning connected to the limbus in 6 cases. Conversely, Salzman degeneration exhibited, a nodular lesion not connected to the limbus with often seen sub basal hyperreflectivity indicating scarring.

HR-OCT proves to be a valuable tool in diagnosing corneal epithelial degeneration, surpassing the limitations of conventional OCT. The detailed imaging provided by the HR-OCT facilitates the identification of subtle changes in corneal structure, enhancing our ability to differentiate and characterize various subtypes of corneal epithelial degenerations and can be used as a replacement of In vivo confocal miscroscopy.