ABSTRACT
A study was carried out on contrast vision in 26 aphakic patients (48 operated eyes) and 37 pseudophakic patients (37 operated eyes); in some cases an intraocular PMMA lens had been implanted, in others an IOGEL (polimacon) had been implanted. The level of sensitivity to contrast in both cases was found to be lower than expected by the Vistech company for aphakics. At the same time a comparative study was carried out of the results obtained for sharpness of vision in aphakic and pseudophakic patients, with the traditional tests of Snellen (long sightedness) and Parinaud (short sightedness) and those obtained with the Contrast Sensitivity Test System (VCTS-6500 for long sightedness and VCTS-6000 for short sightedness). The former tests were found to overestimate the visual results. Corrected aphakia was found to affect the sensitivity to contrast more than in pseudophakic cases. Nevertheless no significant differences were found between contrast vision in eyes with PMMA lens implantation and eyes with IOGEL (polimacon) lens implantation. Summing up, alterations in the sensitivity to contrast undetected by the simple measurement of visual sharpness were found.
