Corneal Topography, Wavefront, Autorefraction, Keratometry and Pupillometry All In One Unit.
The NIDEK OPD-Scan II provides information on corneal topography, wavefront, autorefraction, keratometry and pupillometry in one unit, utilizing state-of-the-art imaging and analysis technology developed specifically to measure normal to highly aberrated eyes. The system offers a variety of data maps to provide information on the total refractive error, wavefront, corneal shape, internal aberrations and visual quality of the eye, allowing highly accurate and reliable information for optic diagnostics.
The OPD-Scan II utilizes the principle of skiascopic phase difference for refractive error map measurement. The retina is scanned with an infrared light slit beam, and the reflected light is captured by an array of rotating photo detectors over a 360 degree area.
The corneal topography function utilizes Placido disc technology. The system captures the image of reflected rings of light from the cornea and analyzes thousands of data points to plot the corneal contour, shape and refractive power.
The OPD-Scan II measures corneal refractive power by corneal topography, and total refractive error as the OPD map. The Internal OPD Map plot is created by subtracting the corneal refractive power from the total OPD to display in diopters the distribution of refractive error contained in the internal eye.
The OPD (Optical Path Difference) map plots the refractive error distribution of total eye aberrations, lower and higher order, in Diopters. This map allows the clinician to easily determine the refractive status and visual quality of the eye with one quick look. This map is unique to the NIDEK OPD-Scan II.
Wavefront High Order Aberration Map
This map shows specific high-order aberration components only, extracted from the total wavefront map. Plotted in microns, this map illustrates the location and degree of high-order aberrations in the eye.
This graph plots all aberration components that make up the aberration profile of the eye, and shows the magnitude of each component such as spherical aberration, coma and trefoil. The graph is used to determine which aberration(s) dominate the aberrations structure of the eye and to what degree. This information may be cnnected to visual symptoms.
Internal OPD Map
This map shows the internal aberrations of the eye. It can be used to distinguish the effects of internal aberrations versus corneal or surface aberrations. For normal corneas, the map indicates the presence of internal astigmatism (especially, lenticular astigmatism), and shows the direct refractive effect of an IOL (such as tilt and haptic torque). This map is also unique to the NIDEK OPD-Scan II.
This is a corneal topography map showing the general surface shape of the cornea. With this map, clinicians can easily recognize such conditions as keratoconus and irregular astigmatism.
This is the actual image of the eye when the measurement is taken. By looking at the actual eye, conditions such as corneal or cataract opacification can be identified. Also displays Photopic and Mesopic images in addition to Placido Ring image.
The OPD SCAN II is the only instrument that couples Wavefront, Topography and Refraction into one unit. This allows the isolation of any optical problem to cornea or crystalline lens making it easy to decide if lensectomy or corneal surgery is the procedure of choice. It also provides the best data for Customized Corneal Refractive Surgery.
-Jack T. Holladay, M.D., M.S.E.E., F.A.C.S.