keratomeetriat

Keratomeetriat is not a standard term in ophthalmology and does not appear in major reference works. It is most likely a misspelling or an uncommon variant of keratometry, the measurement of the curvature and power of the cornea’s anterior surface.

Keratometry derives from the Greek words kerato- (cornea) and -metry (measurement). In practice, keratometry assesses the corneal refractive power, typically expressed in diopters, based on the curvature along the principal meridians of the cornea. Central keratometry values are used to estimate the eye’s total refractive power for part of the prescription in contact lens fitting and refractive surgery planning, and to help calculate intraocular lens power for cataract surgery.

Devices and methods include manual keratometers, which use reflected mires from a known target to determine curvature, and automated keratometers found in many modern refractive and cataract clinics. Corneal topographers and tomographers can provide keratometric data as part of a broader assessment of corneal shape, often reporting K1 (flat meridian) and K2 (steep meridian). Typical central keratometry readings are around 42–44 diopters, corresponding to an average corneal radius of about 7.8 mm, though values vary with individual anatomy and measurement technique.

Procedure generally involves patient alignment, stabilization of the ocular surface, and capture of multiple measurements to improve reliability. Tear film quality, eye aberrations, and instrument calibration can affect accuracy. Keratometric data are integral to refractive error assessment, contact lens fitting, astigmatism evaluation, and preoperative planning for corneal or intraocular procedures.

Related topics include keratometry, corneal topography, and refractive surgery.