Application of Blue Filters Increases the Usefulness of Moreland Test in Anomaloscopic Color Vision Assessment for Blue-Green Color Range.

The effect of blue light filters on the anomaloscopic examination was analyzed. Thirty subjects (18-43 y, 20 female, 10 male) without color vision disorders were examined in 4 filter conditions: no filter (F-0), Blue Control Hoya (F-BC), Med-1 JZO (F-Med1) and 450 Eschenbach (F-450). Both Rayleigh test (red-green axis) and Moreland test (blue-green axis) were performed. Application of F-BC filter shows negligible effect on color vision perception in both tests. Contrary to this, the application of strong F-450 filter causes significant shift in Moreland test towards tritanopy and the decrease in correlations of Moreland parameters with Rayleigh test parameters. The application of medium strong F-Med1 filter causes the slight shift in Moreland test towards the center of the Moreland scale and increases the Spearman correlations between Moreland and Rayleigh test parameters. This observation suggests that the about 15-40% reduction of blue diode intensity in the Moreland test may be beneficial in detecting mild changes in color vision perception in the blue-green axis and may improve its usefulness in evaluating the color vision perception disorders accompanying different illnesses, such as diabetes, glaucoma, neuritis optica, or cataract. The discussion concerning the modifications of Moreland test construction is also presented.

Computerised dynamic posturography for postural control assessment in subjects wearing multifocal contact lenses dedicated for myopia control.

PURPOSE: To measure body balance using computerised dynamic posturography in young adults wearing multifocal contact lenses (MFCL) with high addition powers designed for myopia control. METHODS: Twenty-four young adults (mean age: 24 years) wearing distance-centred soft MFCL (SwissLens Orbis Relax) with two different central zones (3 and 4.5 mm), two addition powers (+2 D, +4 D) and single vision control lenses. Body balance was measured on a moving platform under three viewing conditions: (1) eyes open when fixating on letters at 3 m or (2) at 40 cm, as well as (3) with the eyes closed. Parameters of body stabilisation were analysed: the rate of body stabilisation (τrelax ), the stabilisation time (Tmax ) and the number of oscillations (Nosc ). RESULTS: The MFCLs did not produce a significant difference in the mean values of the analysed parameters (p > 0.05 for τrelax, Tmax, Nosc ). However, a positive correlation was found between pupil size and Nosc and Tmax (p < 0.01), suggesting an effect of the +4 D add with the 3 mm central zone on the posturographic parameters. As was expected, dynamic body stabilisation was better with eyes open versus eyes closed (p < 0.005). CONCLUSIONS: Distance-centred MFCLs with a medium addition (+2 D) do not disturb body stabilisation in young adults. However, high additions (+4 D) with a small central zone may affect body balance control in subjects with large pupil size.