Kang Sung Yong, Hong Samin, Won Jung Bin, Seong Gong Je, Kim Chan Yun
Institute of Vision Research, Department of Ophthalmology, Yonsei University College of Medicine, Seodaemun-Gu, Seoul, Korea.
Yonsei Med J. 2009 Apr 30;50(2):206-10. doi: 10.3349/ymj.2009.50.2.206.
To assess the accuracy of intraocular lens (IOL) power predictions for cataract surgery in eyes with primary angle-closure glaucoma (ACG). Because of shifting of the capsular bag apparatus and shortening of the axial length, preoperative calculation of IOL power may be inaccurate for eyes with ACG.
This retrospective comparative case series comprised of 42 eyes from 42 patients with primary ACG and 45 eyes from 45 subjects with normal open-angles undergoing uneventful cataract surgery. Anterior segment biometry including anterior chamber depth, lens thickness, and axial length were compared. Using the SRK-II formula, the powers of the implanted IOL and the actual postoperative spherical equivalent (SE) refractive errors were compared between the two groups. Also, the absolute values of differences between predicted and residual SE refractive errors were also analyzed for each group.
In ACG patients, anterior chamber depth and axial length were shorter and the lens was thicker than normal controls (all p < 0.001). Even though residual SE refractive error was not significantly different (p = 0.290), the absolute value of the difference between predicted and residual SE refractive error was 0.64 +/- 0.50 diopters in AGC patients and 0.39 +/- 0.36 diopters in control subjects (p = 0.012). The number of eyes that resulted in inaccurate IOL power predictions of more than 0.5 diopters were 21 (50.00%) in the ACG group, but only 12 (26.67%) in the control group (p = 0.043).
IOL power predictions for cataract surgery in ACG patients can be inaccurate, and it may be associated with their unique anterior segment anatomy.
评估原发性闭角型青光眼（ACG）患者白内障手术人工晶状体（IOL）屈光度预测的准确性。由于囊袋装置移位和眼轴长度缩短，ACG患者的IOL屈光度术前计算可能不准确。
本回顾性比较病例系列包括42例原发性ACG患者的42只眼和45例正常开角受试者的45只眼，这些受试者均接受了顺利的白内障手术。比较前节生物测量参数，包括前房深度、晶状体厚度和眼轴长度。使用SRK-II公式，比较两组植入IOL的屈光度和实际术后等效球镜（SE）屈光不正。此外，还分析了每组预测和残余SE屈光不正差异的绝对值。
ACG患者的前房深度和眼轴长度较正常对照组短，晶状体较厚（所有p<0.001）。尽管残余SE屈光不正无显著差异（p=0.290），但ACG患者预测和残余SE屈光不正差异的绝对值为0.64±0.50屈光度，对照组为0.39±0.36屈光度（p=0.012）。IOL屈光度预测误差超过0.5屈光度的眼数在ACG组为21只（50.00%），而对照组仅为12只（26.67%）（p=0.043）。
ACG患者白内障手术的IOL屈光度预测可能不准确，这可能与其独特的前节解剖结构有关。
