In addition to the interocular differences in the horizontal peripheral refraction between the treated and fellow eyes of the NF and FF monkeys, there were eccentricity-dependent, between-group differences in the degree of anisometropia and in the patterns of peripheral refraction for the treated eyes. The left column of
Figure 5 illustrates the average (±SE) refractive corrections obtained at ages corresponding to the end of the treatment period along the horizontal meridian for the normal (top), NF (middle), and FF monkeys (bottom) (treated or right eyes, filled symbols; fellow or left eyes, open symbols). In the normal monkeys, there was a systematic reduction in the degree of hyperopia at all eccentricities between the ages corresponding to the onset and end of the lens-rearing period for the treated monkeys (i.e., emmetropization occurred), and, as expected, the patterns of peripheral refraction for the left and right eyes of the normal monkeys changed very little over time and were well matched at the end of the observation period (
F = 0.23;
P = 0.81). The central refraction of the fellow eyes of the NF and FF monkeys were slightly more hyperopic than those for the control eyes (NF monkeys:
T = −3.07,
P = 0.007; FF monkeys:
T = −1.79,
P = 0.11); however, there were no systematic differences in the magnitude and pattern of peripheral refraction between the fellow eyes of the NF and FF monkeys (
F = 0.93;
P = 0.41). On the other hand, intergroup comparisons showed that there were significant differences in the pattern of horizontal peripheral refraction between the treated eyes of the NF and FF monkeys (
F = 3.65,
P = 0.04). In particular, for the NF monkeys, there were obvious nasal-temporal asymmetries in peripheral refraction along the horizontal meridian (
F = 24.47;
P = 0.0001). Although the absolute treated-eye refractive errors for the FF monkeys were more myopic than those for the NF monkeys at all eccentricities, there were no significant nasal-temporal asymmetries in the pattern of peripheral refraction in the treated eyes of the FF monkeys (
F = 3.73;
P = 0.09). As a consequence of the different patterns of peripheral refraction in the treated eyes, there were significant eccentricity-dependent differences in the degree of anisometropia between the NF and FF monkeys (
F = 11.38;
P = 0.0001). Specifically, the myopic anisometropias for the three nasal field eccentricities were similar in the NF and FF monkeys (
T = 0.52–1.86;
P = 0.09–0.61); however, the NF monkeys exhibited significantly smaller amounts of myopic anisometropia centrally and at all three temporal field eccentricities (
T = 2.69–4.89;
P = 0.003–0.03).