Phenomenological model for interpreting the clinical significance of the in vitro optical transfer function.

We describe a methodology to predict the outcome of clinical tests caused by changes made to the optical elements of the human eye. This formalism, called the expected visual outcome model, is based on in vitro measurements of the optical transfer function and takes into account a simple model of human threshold performance. The clinical tests under consideration are high-contrast visual acuity and contrast sensitivity. Using the expected visual outcome, we describe a useful performance index called the predicted visual acuity graph, which can be measured clinically. The theoretical results are compared with visual function measured in patients with pseudophakic (multifocal and monofocal) implants.