This paper presents a novel processing technique which can be applied to corneal in vivo images obtained with optical coherence tomograms across the central meridian of the cornea. The method allows to estimate the thickness of the corneal sublayers (Epithelium, Bowman’s layer, Stroma, Endothelium, and whole corneal thickness) at any location, including the center and the midperiphery, on both nasal and temporal sides. The analysis is carried out on both the pixel and subpixel scales to reduce the uncertainty in thickness estimations. This technique allows quick and noninvasive assessment of patients. As an example of application and validation, we present the results obtained from the analysis of 52？healthy subjects, each with 3？scans per eye, for a total of more than 300？images. Particular attention has been paid to the statistical interpretation of the obtained results to find a representative assessment of each sublayer’s thickness. 1. Introduction Optical coherence tomography (OCT) based on low coherence interferometry is a well-established imaging technique thanks to its prominent axial resolution. Since 2006, commercially available OCT systems perform visualization of tissue microstructure in the so-called Fourier Domain (FD-OCT). Differently to Time Domain OCT (TD-OCT), the whole depth structure is obtained synchronously providing higher resolution imaging with faster acquisition times. FD-OCT can be used to provide in vivo cross-sectional imaging of the eye in a noninvasive and noncontact way [1]. To date, this technique has been mostly applied to capture retinal structure and optic nerve, displaying and localizing discrete morphological changes in detail [2, 3]. In this paper we use an FD-OCT to study the anterior segment of the eye since this acquisition system can produce cross-sectional images of the cornea, which can be properly processed to analyze corneal sublayers: Epithelium, Bowman’s layer, Stroma, Descemet’s membrane, and Endothelium [4–7]. The precise measurement of these sublayers thickness is very important in ophthalmics and optometrics, for therapeutic treatments, refractive surgery, and contact lens applications. Many works have presented the thickness estimation of corneal sublayers techniques different from OCT. All these approaches have drawbacks and/or introduce some restrictions. Confocal microscopy [8] is an invasive technique that can cause lesions of corneal tissues, while electron microscopy [8, 9] deals only with histopathologic samples, and ultrasonic pachymetry [10] requires the instillation of a topical anaesthetic
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