Colour contrast sensitivity in cataract and pseudophakia

Abstract

ABSTRACT.Purpose: To study the influence of cataract on peripheral and central colour contrast sensitivity. Methods: Peripheral and central colour contrast sensitivity was measured with a computer graphics system along the protan, deutan and tritan axes. Included were 30 patients with cataract divided into three sub-groups: cortical cataract, nuclear sclerosis and posterior subcapsular cataract. Colour contrast was measured before and after cataract operation. Results: There were significant differences in peripheral colour contrast thresholds comparing the preoperative and postoperative results. This difference existed even in patients (nΩ19) with a pre-operative visual acuity Ø0.5 (mean 0.6). The tritan axis was the one most affected by cataract. There was no significant difference between cataract sub-groups. Also, the central colour contrast sensitivity was affected by cataract. Again, the tritan axis was the most affected one. There was no significant difference between the cataract sub-groups. We also found large and significant differences in central colour contrast thresholds between normal subjects and postoperative values from the cataract group in all colour axes. The colour contrast sensitivity was poorer in pseudophakes than in normals. There was a difference between the three groups of different IOL material used (PMMA, acrylic and silicone). The difference was significant in the protan axis, the acrylic group having the best colour contrast sensitivity. Conclusion: Peripheral colour contrast sensitivity was affected by cataract, even when only moderately developed. This finding is of importance and should be considered when the method is used to study other eye diseases e.g. glaucoma. Central colour contrast sensitivity was also affected by cataract. The pseudophakes were found to have poorer colour contrast sensitivity than normals. The material in the IOL seemed to be of importance for colour contrast.

Intraindividual comparison of color contrast sensitivity in patients with clear and blue-light-filtering intraocular lenses

“…21 However, the blue-light filter of the tested IOL filters less blue light and different wavelengths than the lens of a patient scheduled for cataract surgery. 26 The density of blue cones is highest close to the fovea and reduces quickly toward the periphery.…”

“…An increase in color contrast sensitivity was seen in patients who had cataract extraction and implantation of a clear IOL, indicating the cataractous yellowing of the natural lens has a negative effect on color contrast sensitivity. 21 The purpose of this study was to investigate the effect of a blue-light-filtering IOL on color contrast sensitivity by intraindividual comparison of this IOL with an identically designed IOL without a blue-light filter.…”

Detecting chloroquine retinopathy: electro-oculogram versus colour vision

“…On the other hand tritan changes are less specific, as they are more easily affected by other systemic and ocular changes such as media opacities by, for example, cataracts. 54 The computerised colour test used in our study has the advantage that it is relatively insensitive to disturbances in colour perception due to age. 30 Still, some age related changes can be found.…”

Visual performance: Comparison of foldable intraocular lenses

“…2,3 Variable reports on the details of the optical performance of the IOL material and its impact on visual function are available. [4][5][6][7][8][9][10][11][12] The biomaterial of the AcrySof Natural and AcrySof IOLs (Alcon Laboratories) is impregnated with covalently bonded ultraviolet-absorbing chromophore. In addition, the AcrySof Natural IOL contains a covalently bonded chromophore that absorbs light in the 400 to 500 nm range.…”