Department of Ophthalmology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, #505 Banpo-Dong, Seocho-Gu, Seoul 137-701, Republic of Korea.
Exp Eye Res. 2012 Dec;105:9-14. doi: 10.1016/j.exer.2012.08.014. Epub 2012 Oct 12.
The contribution of ciliary muscle to the development and progression of myopia has been addressed. A thickened ciliary muscle in myopia has been speculated as an internal equatorial growth restriction, possibly a matter of hypertrophy with potentially poor contractility, which may result in the development and progression of myopia. In this preliminary study, we evaluated the interrelationship of ciliary muscle characteristics and myopia in 31 volunteers (aged 19-35), via ultrasound biomicroscope (UBM), with eyes focused on far and near targets. Univariate and multivariate regression analysis (using stepwise variable selection) were employed to analyze the relationship between axial length/refractive error and various parameters of ciliary muscle (CM)-cross-sectional area (CMA); length from scleral (CMLs) and vitreous (CMLv) aspects; thickness at 1.0 mm (CMT1), 2.0 mm (CMT2), and 3.0 mm (CMT3) posterior to scleral spur; maximum thickness (CMTm); and apical angle. The impact on accommodation of changes (Δ) in above parameters and of centroid variations was subsequently assessed. In a univariate analysis, axial length showed positive relationship with CMLs (r = 0.454, p = 0.017) and CMT3 (r = 0.460, p = 0.018), and negative relationship with ΔCMTm (r = -0.501, p = 0.008) and Δapical angle (r = -0.400, p = 0.039). Multivariate regression analysis showed that ΔCMTm (β = -0.506, p = 0.008) was independently related with axial length. A negative correlation between CMTm and ΔCMTm was also observed (r = -0.432, p = 0.024). These results suggest that accentuated ciliary muscle thickness, suggesting muscular hypertrophy, may account for the inherent dysfunction in myopia. Further studies are necessary to confirm these preliminary observations and hypotheses.
睫状肌在近视发展和进展中的作用已经得到了探讨。近视患者的睫状肌增厚被推测为赤道内生长受限，可能是肥大的结果，伴有潜在的收缩功能不良，这可能导致近视的发展和进展。在这项初步研究中，我们通过超声生物显微镜（UBM）评估了 31 名志愿者（年龄 19-35 岁）的睫状肌特征与近视之间的相互关系，这些志愿者的眼睛分别聚焦在远距和近距目标上。我们采用单变量和多变量回归分析（使用逐步变量选择）来分析眼轴长度/屈光不正与睫状肌（CM）-横截面积（CMA）；巩膜（CMLs）和玻璃体（CMLv）方面的长度；巩膜突后 1.0mm（CMT1）、2.0mm（CMT2）和 3.0mm（CMT3）处的厚度；最大厚度（CMTm）；和顶端角度的关系。随后评估了上述参数变化（Δ）和质心变化对调节的影响。在单变量分析中，眼轴长度与 CMLs（r=0.454，p=0.017）和 CMT3（r=0.460，p=0.018）呈正相关，与ΔCMTm（r=-0.501，p=0.008）和Δ顶端角度（r=-0.400，p=0.039）呈负相关。多变量回归分析显示，ΔCMTm（β=-0.506，p=0.008）与眼轴长度独立相关。还观察到 CMTm 与ΔCMTm 之间存在负相关（r=-0.432，p=0.024）。这些结果表明，睫状肌厚度增加，提示肌肉肥大，可能是近视固有功能障碍的原因。需要进一步的研究来证实这些初步观察和假设。
