METHOD OF HYPERMETROPIA TREATMENT BY INDUCED HYPERMETROPIC DEFOCUS BASED ON PHYSIOLOGICAL ELONGATION OF EYEBALL IN CHILDREN Russian patent published in 2020 - IPC A61F9/00 

FIELD: medicine.

SUBSTANCE: invention refers to medicine, in particular to ophthalmology. Spherical lenses with dosed hypermetropic defocusing are used. Patient's eye parameters are determined, including eye length in mm, static and dynamic refraction, absolute visual acuity, in diopters, pupil diameter in mm, corneal diameter in mm, radius of curvature of the main meridians of the cornea and average radius of curvature of the cornea. Thereafter, lens parameters are calculated from patient's eye parameters, including lens total diameter and central zone diameter, base curvature radius, refraction in lens optical center (P) and ADD power in the periphery, lens is made in accordance with design parameters, containing on outer surface two smoothly transitioning one into another peripheral and central zones. Latter has shape of circle with diameter from 2000 to 4000 mcm, and with values of Y0 of optical force at measurement points, each of which is determined by following formula: Y0=P+(1-cos(x))k, where x is distance from optical axis of lens to point of measurement of optical power in mm; k is the patient's eye spherical aberration compensation coefficient, which is determined by the following formula: , where Δd is a value equal in value and inverse to the sign of spherical aberration of the eye on the edge of the central region of the optical zone of the lens; and r is radius of central zone of lens in mm; and a peripheral zone concentric to the central zone, with optical power values Y1 at measurement points, each of which is determined by the following formula: Y1=P+((1-cos (x-r)) α)-Δd, where α is coefficient determined by formula . At that, R is radius of central zone of lens in mm; putting the lens on an eye of the patient, aligning its central area with the pupil area of the patient, measuring the visual acuity of the patient in the lens, followed by the therapeutic course. Patient wears the lens for six months, 10-12 hours daily, upon completion of the therapeutic course, repeatedly determining the patient's eye parameters, and, if elongation of eyeball and increased refraction, but not sufficiently, then optical power of lens is changed, making a lens with changed parameters. Thereafter, therapeutic courses are repeated until approaching emmetropization; if the eyeball did not elongate and the refraction remained the same, a lens with the new ADD power parameters is prepared, and the therapeutic courses are repeated until approaching emmetropization.

EFFECT: method enables improving visual acuity, reducing the degree of farsightedness accompanying the eyeball extension by a value higher than the physiological growth value in accordance with the patient's age.

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