Peripheral measurements with the ophthalmometer or keratometer do not give a very accurate representation of the corneal shape since at each fixation point the readings are being taken from two points 3 mm or greater apart. This along with the complex geometry of the cornea makes interpretation of the readings difficult. It may help determine if a particular cornea flattens more or less than average but does not give accurate values.
is now available and gives more accurate information than the keratometer for peripheral corneal shape.
