透明角膜切口超声乳化白内障吸除术前后角膜非球面性分析

Analysis of corneal asphericity in patients after phacoemulsification

目的了解年龄相关性白内障患者的角膜非球面因子Q值的分布情况，探讨超声乳化白内障吸除术前后角膜的非球面变化趋势。方法前瞻性系列病例研究。选择在我院眼科住院的年龄相关性白内障患者30例（39只眼），〈1．00D散光者取颞侧透明角膜切口，≥1．00D散光者在最大曲率子午线作透明角膜切121行超声乳化白内障吸除术，术后3个月进行随访研究，检查项目包括手术前后的角膜Q值、平均角膜曲率、散光度数。对于手术前后角膜Q值、平均角膜曲率、散光度数进行配对t检验，对术前角膜Q值与平均角膜曲率、散光度数进行双变量相关分析。结果手术前后的角膜Q值分别为-0．07±0．22和-0．11±0．16，均呈正态分布趋势，差异无统计学意义（t=1．14，P=0．26）。手术前后的角膜曲率分别为（44．6±1．92）和（44．70±1．47）D，差异无统计学意义（t=-0．69，P=0．50）；术前角膜曲率与角膜Q值成负相关（r=-0．46，P=0．003）。手术前后的散光度数分别为（o．67±0．43）和（0．66±0．42）D，差异无统计学意义（t=-0．24，P=0．82）；术前散光度数与角膜Q值无相关关系（r=-0．24，P=0．14）。结论老年人的角膜Q值大多为负值，呈正态分布，与角膜曲率成负相关。超声乳化白内障吸除术后的角膜Q值比术前略小，差异无统计学意义，手术前后的角膜曲率、散光度数比较差异无统计学意义。

Objective To investigate the distribution of corneal Q-value in the age-related cataract patients and aspherical features of cornea before and after the phacoemulsification （PHACO）. Methods Thirty-nine eyes of 30 age-related cataract patients in our department were included. Transparent cornea incision at the temporal cornea was applied for patients with cornea astigmatism 〈 1.00 D and transparent cornea incision at the maximum curvature meridian for patients with cornea astigmatism ≥ 1.00 D in PHACO. All patients were followed up to 3 months, corneal Q-value, corneal curvature, astigmatism were examined before and after PHACO, distribution of corneal Q-value and their correlation factors were analyzed. Results The mean corneal Q-value before and after the PHACO was - 0. 07 ± 0. 22 and - 0. 11±0. 16, respectively. There was no statistical difference between the corneal Q-values before and after surgery （t = 1.14, P = 0. 26）. The mean of corneal curvature before and after the PHACO was （44. 6 ± 1.92） D and （44. 70 ± 1.47）D, respectively. There was no statistical difference between corneal curvature before and after the operation （t = -0. 69, P = 0. 50）. The corneal Q-value was negatively co-related with corneal curvature before the surgery （ r = - 0. 46, P = 0. 003 ）. The mean astigmatism power before and after the HACO was （0.67±0. 43）D and （0. 66 ±0. 42）D, respectively. There was no statistical difference between astigmatism power before and after the surgery （t = - 0. 24, P = 0. 82）. There was no relationship between the corneal Q-value and astigmatism power before surgery （ r = - 0. 24, P = 0. 14）. Conclusion The corneal Q-value of aged patients is in normal distribution, is negative in the majority, and showed a negative relationship with corneal curvature. There is no statistical difference between the corneal Q-value, corneal curvature, and astigmatism power before and after PHACO surgery.