翼状胬肉对人工晶状体度数测算的影响

Effects of pterygium size on intraocular lens power calculation

摘要:

目的 通过对比不同大小翼状胬肉手术前后角膜曲率和理论人工晶状体（IOL）度数的差异，探讨 翼状胬肉大小对IOL度数测算的影响。方法 选取2016年6月—2017年12月于陕西省中医医院行手术治疗的单眼 原发性鼻侧翼状胬肉患者94例（94眼），根据翼状胬肉长度和宽度分为A组、B组、C组，A组长度<2.0 mm或宽 度<5.0 mm；B组长度2.0～3.5 mm且宽度5.0～7.0 mm；C组长度>3.5 mm～5.0 mm或宽度>7.0 mm。分别于手 术前及术后3个月检查各组患者裸眼视力、矫正视力、眼轴长度、前房深度、平均角膜曲率、角膜散光和理论 IOL度数。结果 随着翼状胬肉大小的增加，各组裸眼视力、矫正视力和角膜散光呈上升趋势（P <0.05），而平 均角膜曲率呈下降趋势（P <0.05）。B、C组术后裸眼视力、矫正视力较术前降低（P <0.05）。B、C组术后平均角 膜曲率较术前高（P <0.05），角膜散光较术前低（P <0.05）。A、B及C组手术前后IOL度数差值分别为（0.13± 0.33）、（0.40±0.58） 和（1.21±1.11） D。结论 当胬肉长度<2.0 mm或宽度<5.0 mm时，对IOL度数测算影响 小；当胬肉长度2.0～3.5 mm，宽度5.0～7.0 mm时，IOL度数测算会产生0.5 D左右的测量误差；当胬肉长度> 3.5 mm～5.0 mm或宽度>7.0 mm时，IOL度数测算误差较大。

Abstract:

Objective To explore the effects of pterygium size on the intraocular lens power calculation by comparing the differences of corneal curvature and theoretical intraocular lens power before and after pterygium surgery. Methods Ninety-four eyes of ninety-four patients with primary nasal pterygium undergoing surgical treatment in our hospital from June 2016 to December 2017 were selected for the study, and were sorted into three groups according to the length and width of pterygium (Group A: length < 2.0 mm or width < 5.0 mm; Group B: length = 2.0 to 3.5 mm and width = 5.0 to 7.0 mm; Group C: 3.5 mm < length ≤ 5.0 mm or width > 7.0 mm). The uncorrected distance visual acuity, corrected distance visual acuity, axial length, anterior chamber depth, average corneal curvature, corneal astigmatism and theoretical intraocular lens power were measured before operation and 3 months after operation. Results Before the surgery, with the increase of pterygium size, uncorrected distance visual acuity, corrected distance visual acuity and corneal astigmatism were increased (P < 0.05), while average corneal curvature was decreased (P < 0.05). The uncorrected distance visual acuity, corrected distance visual acuity and corneal astigmatism were lower after the surgery in group B and C (P <0.05). However, the average corneal curvature was higher after the surgery in group B and C (P < 0.05). The differences of theoretical intraocular lens power before and after surgery in group A, B, C were (0.13 ± 0.33) D, (0.40 ± 0.58) D, and (1.21 ± 1.11) D, respectively. Conclusions The effect of pterygium size on the intraocular lens power calculation is slight when the length of pterygium is less than 2.0 mm or the width of pterygium is less than 5.0 mm. The measurement error of intraocular lens power is about 0.5 D when the pterygium length is 2.0 to 3.5 mm and the width is 5.0 to 7.0 mm. Nevertheless, the measurement error of intraocular lens power is much greater when the pterygium length is more than 3.5 mm but no more than 5.0 mm or the width is more than 7.0 mm.