Toward building an anatomically correct solid eye model with volumetric representation of retinal morphology (original) (raw)

Three-dimensional OCT based guinea pig eye model: relating morphology and optics

Biomedical Optics Express

Custom Spectral Optical Coherence Tomography (SOCT) provided with automatic quantification and distortion correction algorithms was used to measure the 3-D morphology in guinea pig eyes (n = 8, 30 days; n = 5, 40 days). Animals were measured awake in vivo under cyclopegia. Measurements showed low intraocular variability (<4% in corneal and anterior lens radii and <8% in the posterior lens radii, <1% interocular distances). The repeatability of the surface elevation was less than 2 µm. Surface astigmatism was the individual dominant term in all surfaces. Higher-order RMS surface elevation was largest in the posterior lens. Individual surface elevation Zernike terms correlated significantly across corneal and anterior lens surfaces. Higher-orderaberrations (except spherical aberration) were comparable with those predicted by OCTbased eye models.

Working sketch of an anatomically and optically equivalent physical model eye

Proceedings of …, 2009

Our aim was to fabricate a bench-top physical model eye that closely replicates anatomical and optical properties of the average human eye, and to calibrate and standardize this model to suit normal viewing conditions and subsequently utilize it to understand the optical performance of corrective lens designs; especially multifocal soft contact lenses. Using available normative data on ocular biometrics and Zemax ray-tracing software as a tool, we modeled 25, 45 and 55 year-old average adult human eyes with discrete accommodation levels and pupil sizes.

Finite schematic eye models and their accuracy to in-vivo data

Vision research, 2008

Measurement of ocular wavefront aberration is becoming a popular clinical technique due to recent technical advances and an increasing awareness of its potential for practical application in the fields of surgical and optical refractive correction. In addition, information about the status of peripheral refraction determined from ocular wavefront aberrations is now being used to monitor the progression of myopia and other refractive errors in children, and as a basis for the study of the process of emmetropization. Several finite, anatomically accurate, wide-angled, model eyes have been proposed previously in an effort to produce a schematic eye that accurately reproduces vision under different practical circumstances. This paper compares these models in terms of their wavefront aberration, image quality metrics and peripheral refraction profiles and contrasts these with data from real eyes to assess their relative utility.

3D OCT imaging in clinical settings: toward quantitative measurements of retinal structures

Proceedings of the SPIE - The International Society for Optical Engineering, 2006

The acquisition speed of current FD-OCT (Fourier Domain -Optical Coherence Tomography) instruments allows rapid screening of three-dimensional (3D) volumes of human retinas in clinical settings. To take advantage of this ability requires software used by physicians to be capable of displaying and accessing volumetric data as well as supporting post processing in order to access important quantitative information such as thickness maps and segmented volumes.

Optic nerve head three-dimensional shape analysis

Journal of biomedical optics, 2018

We present a method for optic nerve head (ONH) 3-D shape analysis from retinal optical coherence tomography (OCT). The possibility to noninvasively acquire in vivo high-resolution 3-D volumes of the ONH using spectral domain OCT drives the need to develop tools that quantify the shape of this structure and extract information for clinical applications. The presented method automatically generates a 3-D ONH model and then allows the computation of several 3-D parameters describing the ONH. The method starts with a high-resolution OCT volume scan as input. From this scan, the model-defining inner limiting membrane (ILM) as inner surface and the retinal pigment epithelium as outer surface are segmented, and the Bruch's membrane opening (BMO) as the model origin is detected. Based on the generated ONH model by triangulated 3-D surface reconstruction, different parameters (areas, volumes, annular surface ring, minimum distances) of different ONH regions can then be computed. Addition...

Contribution of the ocular surface to visual optics

Experimental Eye Research, 2004

The air/tear interface contributes 70% of the vergence in the eye and, because of this, even minor variations in its shape can produce significant visual deficit. Placido disc-based corneal topographers measure the precise characteristics of the corneal surface, transforming shape into color-coded dioptric power maps and topography indexes related to optical quality and specific patterns associated with pathology. Artificial intelligence-based methods are used to classify corneal topography and these are used as screening tools. Coupling corneal topography measurements with aberrometry measurements permits the display of the internal aberrations of the eye. Together, these data provide the opportunity to extend refractive correction beyond sphere and cylinder to the higher order aberrations as well.