OBJECTIVE To calculate the keratometric (K) reading in corneas modified by myopic keratorefractive surgery using the total corneal refractive power (TCRP) of the Pentacam rotating Scheimpflug camera. METHODS University hospitals and private clinics, South Korea METHODS Evaluation of diagnostic test or technology. METHODS The study comprised healthy eyes, eyes having myopic keratorefractive surgery, and eyes having cataract surgery after myopic keratorefractive surgery. The conversion equation from the TCRP in the central 4.0 mm zone (TCRP4) to a K reading was derived in normal corneas. This equation was rechecked and its application range extended in corneas modified by myopic keratorefractive surgery. Then, the predictability of the TCRP method, combining the K reading derived from the TCRP4 and the Holladay 2 formula, was evaluated in a case series of cataract surgery patients who had previous myopic keratorefractive surgery. RESULTS The K reading derived from the TCRP4 was obtained by adding 0.7 diopter (D). This conversion factor was applicable after myopic keratorefractive surgery because changes in TCRP4 were equal to changes in refraction in the 4.0 mm zone. The TCRP method predicted intraocular lens power within ± 0.5 D in 83% and within ± 1.0 D in 94% of eyes having cataract surgery after myopic keratorefractive surgery. CONCLUSIONS The TCRP4 of the rotating Scheimpflug camera was successfully converted into the equivalent K reading, and the TCRP method showed good predictability in corneas modified by myopic keratorefractive surgery. BACKGROUND No author has a financial or proprietary interest in any material or method mentioned.