Miles Center for Pediatric Ophthalmology, Storm Eye Institute, Department of Ophthalmology, Medical University of South Carolina, Charleston, South Carolina.
Ophthalmology. 2013 Oct;120(10):1973-6. doi: 10.1016/j.ophtha.2013.03.013. Epub 2013 May 21.
To provide guidelines for the selection of an initial contact lens (CL) power based on the preoperative characteristics of the patient in eyes undergoing infantile cataract surgery without primary intraocular lens (IOL) implantation.
Cohort study.
Eyes were included if cataract surgery was performed without primary IOL implantation before 1 year of age, a SilSoft CL (Bausch & Lomb, Rochester, NY) was placed immediately after surgery, and postoperative refraction data were available within 1 month after surgery.
The target CL power was calculated by using the postoperative refraction at the corneal plane for each eye. A regression formula was derived using the targeted CL power and the axial length (AL). The CL power also was estimated using various formulas. An A-constant was derived to estimate CL power using IOL power calculation formula.
Contact lens power.
Fifty eyes of 50 patients were analyzed. Age at the time of cataract surgery was 2.4 ± 1.7 months. Refraction at the corneal plane was 29.6 ± 4.4 diopters (D). Regression analysis revealed that CL power=84.4 - 3.2 × AL (R(2) = 0.82; P<0.001). Contact lens power can be estimated using an A-constant of 112.176 in the IOL power calculation formula. If a CL power of 32 D had been used, 22 (44%) of 50 eyes would have needed a replacement of CL.
We devised guidelines on selecting the initial CL power based on preoperative AL. The IOL power calculator also can help to estimate CL power. Refraction at the conclusion of surgery in infants may be difficult, and preoperative biometry can be used to estimate CL power.
FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.
为婴儿期白内障手术后未植入一期人工晶状体(IOL)的患者,提供基于术前特征选择初始隐形眼镜(CL)度数的指南。
队列研究。
如果白内障手术在 1 岁前未植入一期 IOL 而进行,术后立即放置 SilSoft CL(Bausch & Lomb,Rochester,NY),并且术后 1 个月内可获得术后屈光数据,则纳入该研究。
使用每只眼的角膜平面术后屈光度计算目标 CL 度数。通过目标 CL 度数和眼轴(AL)推导出回归公式。还使用各种公式估算 CL 度数。得出 A-常数以使用 IOL 度数计算公式估算 CL 度数。
CL 度数。
共分析 50 例 50 只眼。白内障手术时的年龄为 2.4±1.7 个月。角膜平面屈光度为 29.6±4.4 屈光度(D)。回归分析显示 CL 度数=84.4-3.2×AL(R²=0.82;P<0.001)。可使用 IOL 度数计算公式中的 A-常数 112.176 估算 CL 度数。如果使用 32 D 的 CL 度数,50 只眼中的 22 只(44%)需要更换 CL。
我们制定了基于术前 AL 选择初始 CL 度数的指南。IOL 度数计算器也可帮助估算 CL 度数。在婴儿中,手术结束时的屈光度可能难以测量,术前生物测量可用于估计 CL 度数。
作者在本文讨论的材料中没有任何专有或商业利益。