METHOD FOR DETERMINING THE OPTICAL FORCE OF THE INTRAOCULAR LENSE AFTER RADIAL KERATOTHOMY Russian patent published in 2018 - IPC A61F9/07 A61F2/16 A61B5/107 

FIELD: medicine.

SUBSTANCE: invention relates to medicine, namely ophthalmosurgery. To determine the optical strength of the intraocular lens (IOL) in patients with cataracts after radial keratotomy, a radius of the anterior surface bending of the cornea is measured in the central optical zone with a diameter of 1.5÷3.0 mm (R_P, mm) and eye length (L, mm). Optical strength of the IOL (P_iol, dptr) is calculated by the formula:

where R_z (mm) – radius of posterior surface bending of the cornea: R_z=2.055×R_P+0.025×L-0.016×R_P×L-7.234; C (mm) – position of the second main focal point of the combined optical system "cornea – anterior chamber – IOL": C =-0.055×R_z²+1.189×R_z-4.055, N (mm) – the effective position of the IOL, calculated by the formula:

where A (conditional units) – A-constant IOL; W (mm) – corneal diameter:

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EFFECT: method makes it possible to increase the accuracy of determining the optical strength of the IOL after radial keratotomy, by measuring the minimum possible number of eye parameters, no need for refractive data preceding radial keratotomy and taking into account the individual parameters of the eye optical system, calculated from empirically derived formulas.

1 cl, 2 dwg, 2 tbl