Institute of Vision & Optics, University of Crete, Heraklion, Crete, Greece.
Ophthalmic Physiol Opt. 2013 Jan;33(1):42-50. doi: 10.1111/opo.12004. Epub 2012 Dec 1.
To evaluate the effects of the wearer's pupil size and spherical aberration on visual performance with centre-near, aspheric multifocal contact lenses (MFCLs). The advantage of binocular over monocular vision was also investigated.
Twelve young volunteers, with an average age of 27 ± 5 years, participated in the study. LogMAR Visual Acuity (VA) was measured under cycloplegia for a range of defocus levels (from +3.0 to -3.0 D, in 0.5 D steps) with no correction and with three aspheric MFCLs (Air Optix Aqua Multifocal) with a centre-near design, providing correction for 'Low', 'Med' and 'High' near demands. Measurements were performed for all combinations of the following conditions: (1) artificial pupils of 6 and 3 mm diameter, (2) binocular and monocular (dominant eye) vision. Depth-of-focus (DOF) was calculated from the VA vs defocus curves. Ocular aberrations under cycloplegia were measured using iTrace.
VA at -3.0 D defocus (simulating near performance) was statistically higher for the 3 mm than for the 6 mm pupil (p = 0.006), and for binocular rather than for monocular vision (p < 0.001). Similarly, DOF was better for the 3 mm pupil (p = 0.002) and for binocular viewing conditions (p < 0.001). Both VA at -3.0 D defocus and DOF increased as the 'addition' of the MFCL correction increased. Finally, with the centre-near MFCLs a linear correlation was found between VA at -3.0 D defocus and the wearer's ocular spherical aberration (R(2) = 0.20 p < 0.001 for 6 mm data), with the eyes exhibiting the higher positive spherical aberration experiencing worse VAs. By contrast, no correlation was found between VA and spherical aberration at 0.00 D defocus (distance vision).
Both near VA and depth-of-focus improve with these MFCLs, with the effects being more pronounced for small pupils and for binocular rather than monocular vision. Coupling of the wearer's ocular spherical aberration with the aberration profiles provided by MFCLs affects their functionality.
评估佩戴者瞳孔大小和球差对中心-近距、非球面多焦点隐形眼镜（MFCL）视觉性能的影响。还研究了双眼视觉相对于单眼视觉的优势。
12 名平均年龄为 27 ± 5 岁的年轻志愿者参与了这项研究。在睫状肌麻痹下，使用 LogMAR 视力（VA）测量一系列离焦水平（从+3.0 到-3.0 D，每 0.5 D 一步），不进行矫正，并用三种中心-近距设计的非球面 MFCL（Air Optix Aqua Multifocal）进行矫正，提供“低”、“中”和“高”近距需求的矫正。在以下条件的所有组合下进行测量：（1）人工瞳孔直径为 6 和 3 mm，（2）双眼和单眼（主导眼）视觉。从 VA 与离焦曲线计算景深（DOF）。使用 iTrace 测量睫状肌麻痹下的眼像差。
-3.0 D 离焦（模拟近距表现）时，3 mm 瞳孔的 VA 明显高于 6 mm 瞳孔（p = 0.006），且双眼视觉优于单眼视觉（p < 0.001）。同样，3 mm 瞳孔（p = 0.002）和双眼视觉条件（p < 0.001）下的 DOF 更好。随着 MFCL 矫正的“附加”增加，-3.0 D 离焦时的 VA 和 DOF 都增加。最后，在中心-近距 MFCL 中，-3.0 D 离焦时的 VA 与佩戴者的眼像差呈线性相关（6 mm 数据的 R²=0.20 p < 0.001），具有较高正球差的眼睛表现出更差的 VA。相比之下，在 0.00 D 离焦（远距视力）时，VA 与球差之间没有相关性。
这些 MFCL 可提高近距 VA 和景深，小瞳孔和双眼视觉的效果更明显。佩戴者的眼像差与 MFCL 提供的像差曲线的结合影响其功能。
