<unk>  showing stage II keratoconus. Computerized<unk>  can be employed for diagnostics. It is, in fact, one of the exams the patients have to undergo prior to the Cross-linking and the Mini Asymmetric Radial Keratotomy (M.A.R.K.). For example, the KISA% index (keratometry, I-S, skew percentage, astigmatism) is used to arrive at a diagnosis of keratoconus, to screen the suspect keratoconic patients and analyse the degree of corneal steepness changes in healthy relatives. Nevertheless,<unk>  in itself is a measurement of the first reflective surface of the eye (tearfilm) and is not giving any additional information beside the shape of this layer expressed in curvature. Keratoconus in itself is a pattern of the entire cornea, therefore every measurement just focusing on one layer, might not be enough for a state of the art diagnosis. Especially early cases of keratoconus might be missed by a plain<unk> c measurement, which is critical if refractive surgery is being considered. The measurement is also sensitive to unstable tearfilms. Also, the alignment of the measurement can be difficult, especially with eyes that have Keratoconus, a significant astigmatism, or sometimes after refractive surgery.<unk>  instruments generate a measurement called simulated keratometry (SimK), which approximates the classic measurement of the widely used keratometer. Another novel use of<unk> c data is called CorT, which has been shown to quantify refractive astigmatism more accurately than SimK and other approaches. CorT utilizes data from all Placido rings across the cornea compared with SimK, which is based on only one ring. While<unk>  relies on reflected light from the front (anterior) of the cornea, a technique called<unk>  also provides a measure of the back (posterior) shape of the cornea. A measure called CorT total includes this posterior corneal data and more accurately reflects refraction compared with regular CorT, SimK, and other techniques.
Corneal topography
Corneal pachymetry
Scanning laser ophthalmoscopy
Doppler optical coherence tomography
Ocular tonometry
Eye testing using speckle
Exophthalmometer
Retinal birefringence scanning