A High-tech New Device Eyevispod™ Helps Evaluate Refractive Lens Surgery and Other Presbyopic Surgeries On Near and Intermediate Vision Quality

Abstract

Presbyopia-correcting intraocular lenses (Pr-C IOLs) can provide a full range of visual corrections for far, intermediate and near vision. It is important to evaluate the outcomes from Pr-C IOLs in order to improve our results. Experience has taught us to test for certain parameters that best correlate with the patient's real-life visual performance and satisfaction. We have developed a system to collect important pre-and post-operative data to accurately access Pr-C IOLs' effectiveness. The first parameter is the patient's visual acuity. The minimum size letter that a person can resolve at near distance is an important measure of their near vision. It is important to standardise the measurement, which has been performed well for distance acuity, but not for near acuity. The latter is regularly reported in Snellen or Jaeger number formats in the US, N numbers in the UK and Parinaud numbers in France. Due to these differing systems, no comparisons can be drawn among different studies. Our experience has also shown that patients often require a print size two or three times larger than their peak near acuity limits before they can achieve their maximum reading speed. It would be useful to have a standardised method of measuring near vision that was more easily translatable into other formats.The second parameter to consider is reading speed. In our experience, it is common for a patient not to be able to comfortably The third parameter is depth of focus. Different IOLs can be expected to perform differently at different distances when reading. The defocus curve is a very useful piece of data for us to better understand the visual performance of a specific IOL: if a Pr-C IOL is found to have a predictable defocus curve, this information can be valuable for the patient's selection and counselling. The fourth parameter to evaluate is the patient's spectacle dependency after surgery. This is a rather objective criterion -if someone does not ever use glasses, this is a very definite end-point. Likewise, the presence or absence of photic phenomena is important. Although, rather than having the patient respond either yes or no, it is much more indicative to quantify the amount and severity of these events. visual outcomes will lead to a greater standardisation of clinical methods traditionally used to measure near acuity. A High-tech New Device Eyevispod™ Helps Evaluate Refractive Lens Surgery and Other Presbyopic Surgeries On Near and Intermediate Vision Quality