| 摘要 |
Multifocal corneal refractive surgery for the correction of presbyopia is optimized, based on patient pupil measurements and acuity requirements. Measurements are made of the patient's pupil dimensions in bright and dim light, with near and distant focusing. A series of mathematical models of the wavefront transmitted through the eye/multifocal optic system is constructed, and the modulation transfer functions are calculated, for a series of optical zone dimensions and decentrations. The maximum resolvable spatial frequency and the expected visual acuity are calculated as functions of the zone dimensions and decentration. The patient's near and distant visual acuity requirements are compared to the expected visual acuity, and the optimized zone dimensions and decentration meeting the acuity requirements are determined. A required postoperative multifocal corneal profile is calculated. A computer-controlled laser, mechanical, thermal, or conductive device reshapes the cornea or a corneal implant. Nomograms are disclosed for centered, circular multifocal refractive surgery.
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