Dual-focus lenses that impose simultaneous competing myopic defocus over the entire visual field produce axial hyperopic shifts in refractive error. The purpose of this study was to characterize the effects of eccentricity on the ability of myopic defocus signals to influence central refractive development in infant monkeys. From 24 to 152 days of age, rhesus monkeys were reared with binocular, dual-focus lenses that had central, zero-powered zones surrounded by alternating concentric annular power zones of +3D and zero power. Between subject groups the diameter of the central, zero-powered zone was varied from 2 mm to 8 mm in 2 mm steps (+3D/pl 2 mm, n = 6; +3D/pl 4 mm, n = 6; +3D/pl 6 mm, n = 8, or + 3D/pl 8 mm, n = 6). For the treatment lens with 2, 4, 6 and 8 mm central zones, objects at eccentricities beyond 11°, 16°, 19° and 23°, respectively, were imaged exclusively through the dual-power peripheral zones. Refractive status (retinoscopy), corneal power (keratometry) and axial dimensions (ultrasonography) were measured at two-week intervals. Comparison data were obtained from monkeys reared with binocular, single-vision +3D full-field lenses (+3D FF, n = 6) and 41 normal control monkeys reared with unrestricted vision. At the end of the rearing period, with the exception of the +3D/pl 8 mm group (median = +3.64 D), the ametropias for the other lens-reared groups (medians: FF = +4.39 D, 2 mm = +5.19 D, 4 mm = +5.59 D, 6 mm = +3.50 D) were significantly more hyperopic than that for the normal monkeys (+2.50 D). These hyperopic errors were associated with shallower vitreous chambers. The key finding was that the extent and consistency of these hyperopic ametropias varied with the eccentricity of the dual-focus zones. The results confirm that myopic defocus in the near periphery can slow axial growth, but that imposed defocus beyond about 20° from the fovea does not consistently alter central refractive development.

双焦点镜片在整个视野上同时施加竞争性近视散焦，导致屈光不正的轴向远视偏移。本研究的目的是表征离心率对近视散焦信号影响婴儿猴子中央屈光发育的能力的影响。从 24 日龄到 152 日龄，恒河猴饲养双目双焦点镜片，该镜片具有中央零倍率区，周围环绕着交替的 3D 和零倍率同心环形倍率区。在受试者组之间，中央零倍率区的直径以 2 mm 的步长从 2 mm 变化到 8 mm（+3D/pl 2 mm，n = 6；+3D/pl 4 mm，n = 6；+3D /pl 6 毫米，n = 8，或 + 3D/pl 8 毫米，n = 6）。对于具有 2、4、6 和 8 毫米中心区的治疗镜片，偏心度超过 11°、16°、19° 和 23° 的物体，分别通过双电源外围区域专门成像。每两周测量一次屈光状态（检影）、角膜屈光度（角膜曲率）和轴向尺寸（超声检查）。比较数据来自用双目单视 +3D 全视野镜片（+3D FF，n = 6）饲养的猴子和 41 只用无限制视力饲养的正常对照猴子。在饲养期结束时，除了 +3D/pl 8 mm 组（中位数 = +3.64 D）外，其他晶状体饲养组的屈光不正（中位数：FF = +4.39 D，2 mm = + 5.19 D, 4 mm = +5.59 D, 6 mm = +3.50 D) 比正常猴子 (+2.50 D) 的远视度明显更高。这些远视错误与较浅的玻璃体腔有关。关键发现是这些远视屈光不正的程度和一致性随着双焦点区的偏心而变化。结果证实，近周边的近视散焦会减慢轴向增长，但在距中央凹约 20° 以外强加的散焦并不会始终如一地改变中心屈光发育。