A keratoscope fitted with a video camera.
An electro-optical instrument for measuring the corneal topography. It produces a colour coded three-dimensional map of the shape of the cornea and of the dioptric power of the different corneal regions. These instruments are computer-assisted, providing rapid, online analysis of the image and most of them are based on the corneal reflection of the Placido pattern. Topographic data are usually presented as a colour-coded map of the cornea showing regions of different power. These instruments are used to evaluate keratoconus, irregular corneal shape, contact lens fitting, monitor the cornea after keratoplasty or refractive surgery, etc. There are many commercial models including one that provides a map of the curvature and elevation of the anterior and posterior corneal surface (scanning-slit videokeratoscope). See corneal topography; keratoscope; photokeratoscope; Topogometer.