Expert in statistics to create power and sample size calculation

I need a power and sample size calculation. Before and after surgery I will measure two variables: the steropsis as a function of aniseikoni (Figure 1). The purpose of the study is to find differences before and after surgery. I need to know how many persons to measure that on. I have very limited background information from other studies as this has been rarely performed. But this I know from another study: From 17 persons as reference we know that: The amount of aniseikonia ranged from 0.1 to 10.4% (mean [TSD], 1.9% [T0.5%]) at visit 1, 0.9 to 18.9% (mean [TSD], 6.2% [T1.2%]) at visit 2, and 0.1 to 4.4% (mean [TSD], 1.5% [T0.3%]) at visit 3. For anisometropia, the range was 0 to 4.12 D (mean [TSD], 0.98 [T0.27] D) at visit 1, 1.62 to 11 D (mean [TSD], 3.84 [T0.58] D) at visit 2, and 0 to 2.87 D (mean [TSD], 0.63 [T0.18] D) at visit 3. The only visit at which anisometropia and aniseikonia were significantly correlated was visit 1 (R2 = 0.70, p G 0.001). At visits 2 and 3, respectively, coefficients of concordance were 0.001 (p 9 0.05) and 0.10 (p 9 0.05). Analysis of variance (main effects p G 0.001) and Tukey test in- dicated that both anisometropia and aniseikonia increased sig- nificantly at visit 2 (p G 0.05) and then decreased significantly at visit 3 (p G 0.05). Whereas anisometropia and aniseikonia increased at visit 2 and decreased at visit 3, individual changes at visit 2 in particular indicated considerable variability and were not always as pre-dicted. Changes in aniseikonia were predicted from the magnitude of anisometropia induced by unilateral cataract surgery accordingto the magnification of the spectacle lens in front of the phakic eye.A patient with +5 D correction in each eye would develop a greaterincrease in aniseikonia after unilateral cataract surgery than a patient with +2 D correction in each eye. Fig. 2 illustrates the greater variability in the changes in aniseikonia versus changes in anisometropia between visit 2 and visit 1 and less variability between visit 3 and visit 1. You can see the full article / study attached as well. Also I know the steropsis (Figure 2). Please notice that I know nothing about statistics.