CSO IOL Calculation Module

The IOL (Intraocular Lens) calculation software available in CSO’s (Costruzione Strumenti Oftalmici) instruments is a ray-tracing application based on the measured parameters of the ocular anterior segment. The altimetric data of the anterior and posterior corneal surfaces and the positions of the iris and scleral spurs are used in combination with the altimetric data of the IOL to build a three-dimensional model of the eye. For each simulated ray entering the pupil of the eye, the software calculates its intersection with any optical interface and applies Snell’s refraction law to get the direction of the refracted ray. The position of the IOL is predicted with a proprietary algorithm based on the positions of the iris and scleral spurs. With a given IOL model and power, this software predicts the postoperative sphere, cylinder, refractive map, point spread function (PSF) and focusing chart. Unlike standard thin-lens formulas, this method is not affected by previous corneal surgery and can be used in eyes with any corneal disease or surgical history.