PRESBYpath converts a patient’s data — refraction, keratometry, asphericity and higher-order wavefront — into a custom multifocal corneal profile for presbyopic LASIK or PRK. The optimiser computes an asphericity change (ΔQ) or a combination of Zernike polynomials, together with a spherical addition, so as to maintain good image quality across the whole intended pseudo-accommodative vergence range, and for two pupil diameters at once (distance vision under mesopic conditions and near vision in myosis). Its distinctive feature is that it renders a vergence map expressed directly in dioptres rather than in microns of optical path difference.
Key features
- Design of patient-specific multifocal LASIK / PRK profiles
- Optimisation by an image-quality score across two pupils and the whole depth of field
- Two laser-programming strategies: modulating asphericity Q or spherical aberration
- Quality index combining MTF (MTF/MTFa), PSF, Strehl ratio and depth of field
- Vergence map in dioptres (total / low-order / higher-order aberrations)
- Ablation-profile audit, simulated optotype rendering and a Z(4,0) fallback mode without aberrometry