Bessel function model of corneal topography

Corneal Topography Analysis of Stromal Corneal Dystrophies

OBJECTIVE The aim was to compare the corneal topography and tomography parameters of macular corneal dystrophy (MCD), granular corneal dystrophy (GCD) and lattice corneal dystrophy (LCD) patients obtained by Scheimpflug imaging system. METHODS The charts, photographs and topography images of patients were reviewed retrospectively. This study included 73 eyes of 73 patients (28 MCD, 20 GCG and...

Corneal topography by keratometry.

AIMS To investigate the ability of a telecentric keratometer to describe the asphericity and curvature of convex ellipsoidal surfaces and human corneas. METHODS 22 conicoidal convex surfaces and 30 human corneas were examined by conventional keratometry. Additional keratometric measurements were made when the surface was tilted in the horizontal plane relative to the instrument optical axis. ...

Evaluation of corneal thickness and topography in normal eyes using the Orbscan corneal topography system.

AIMS To map the thickness, elevation (anterior and posterior corneal surface), and axial curvature of the cornea in normal eyes with the Orbscan corneal topography system. METHODS 94 eyes of 51 normal subjects were investigated using the Orbscan corneal topography system. The anterior and posterior corneal elevation maps were classified into regular ridge, irregular ridge, incomplete ridge, i...

Keratoconus detection using corneal topography.

UNLABELLED PURPOSETo review the topographic patterns associated with keratoconus suspects and provide criteria for keratoconus screening. METHODS Case study using maps from the NIDEK OPD-Scan II and OPD Station to highlight patterns seen in keratoconic corneas. RESULTS Five criteria are listed for the detection of keratoconus: 1) apex of the cone is not centered at the 6-o'clock semi-meridi...

Information fidelity in corneal topography.