目的：分析角膜后前表面曲率半径比值(B/F比值)与年龄相关性白内障患者术后屈光误差的关系，探讨B/F比值对人工晶状体(intraocular lens,IOL)度数计算精确性的影响。方法：选取2019年3—11月在天津医科大学眼科医院白内障中心就诊，并拟行单眼白内障手术的年龄相关性白内障患者共197例(197眼)，术前应用Pentacam眼前节分析仪测量患者眼前节生物参数，并以B/F比值下限25%、上限25%为界将患者分为下25%组、25%～75%组、上25%组。术后3个月应用全自动电脑验光仪评估患者术后屈光状态，并计算患者术后屈光误差(postoperative refractive error,PE)，比较三组平均屈光误差(mean refractive error,ME)、平均绝对误差(mean absolute error,MAE)、中位数绝对误差(median absolute error,MedAE)以及屈光误差在±0.25、±0.50、±0.75、±1.00、>±1.00 D范围内百分比差异。结果：B/F比值与年龄相关性白内障患者术后屈光误差呈中度相关(r=?0.445, P<0.001)。随着B/F比值增大，患者术后屈光状态由远视向近视漂移，术后3个月MAE、MedAE分别为0.55 D、0.46 D。屈光误差在±0.25、±0.50、±0.75、±1.00、>±1.00 D范围的百分比分别为29.4%、52.8%、71.6%、87.6%、12.7%。根据正常年龄相关性白内障人群B/F比值优化得到的矫正角膜折射指数计算角膜曲率后，MAE、MedAE分别为0.51、0.43 D，均低于矫正前(P<0.05)。结论：B/F比值对年龄相关性白内障患者术后屈光状态有影响。随着B/F比值的增加，白内障患者术后屈光状态由远视逐渐向近视漂移，且B/F比值越偏离正常平均值，患者的屈光误差绝对值越大。

Objective: To analyze the relationship between corneal B/F ratio and postoperative refractive error in age-related cataract patients, and to explore the impact of B/F ratio on the accuracy of intraocular lens power calculation. Methods: A total of 197 age-related cataract patients (197 eyes) who were treated in the cataract center of our hospital from March 2019 to November 2019 and were going to undergo monocular cataract surgery were selected. The biological parameters of the anterior segment were measured by Pentacam anterior segment analyzer before surgery, and the patients were divided into three groups (25% below the B/F ratio, 25%~75%, and 25% below the B/F ratio) with the lower limit and the upper limit of 25%. Three months after surgery, the postoperative refractive state of patients was evaluated by automatic computerized refractometer, and the postoperative refractive error (PE) was calculated, and the percentage differences of mean refractive error (ME), mean absolute error (MAE), median absolute error (MedAE) and refractive error in the range of ±0.25, ±0.50, ±0.75, ±1.00 and < ±1.00D were evaluated. Results: The B/F ratio was moderately correlated with postoperative refractive error in age-related cataract patients (r= ?0.445, P < 0.001). With the increase of B/F ratio, the refractive state of patients shifted from hyperopia to myopia after surgery, and the MAE and MedAE were 0.55 D and 0.46 D respectively in 3 months after surgery. The percentages of refractive error in the range of ±0.25, ±0.50, ±0.75, ±1.00 and < ±1.00 D were 29.4%, 52.8%, 71.6%, 87.6% and 12.7%, respectively. After adjusting the corneal curvature according to the B/F ratio of the population based on our previous study, MAE and MedAE were 0.51 D and 0.43 D, respectively, which were lower than those before correction (P< 0.05). Conclusions: There is a correlation between B/F ratio and postoperative refractive error in age-related cataract patients. As the B/F ratio increased, the refractive state of the patient gradually drifted from farsightedness to myopia after cataract surgery, and the more the B/F ratio deviated from the normal average, the greater the absolute value of the patient's refractive error.

目的：观察后房型有晶体眼人工晶体(implantable collamer lens，ICL)V4c植入术后2年的有效性、安全性和稳定性，评估ICL V4c矫正屈光不正的中远期临床疗效。方法：回顾性病例研究。收集在河 北省沧州市中心医院眼一科行ICL V4c手术治疗的屈光不正患者，观察并记录术前至术后2年的裸眼视力、最佳矫正视力、屈光状态、对比敏感度、高阶像差、眼压、人工晶体拱高、角膜内皮细胞 计数、不良反应、主观视觉质量等临床资料，进行统计学分析。结果：完成随访的96例术眼，术后2年的平均裸眼视力(LogMAR)为0.021±0.065，平均最佳矫正视力(LogMAR)为0.002±0.041，优于术前最佳矫正视力，有效性指数为1.05，安全性指数为1.09，等效球镜数值稳定，对比敏感度提升，高阶像差有所增加，但主观视觉质量良好，眼压基本稳定，内皮细胞丢失率为1.6%，平均拱高为(549.6±50.0) μm，随访期间未发现眼内感染、继发性青光眼、晶状体混浊、黄斑水肿、视网膜脱离等并发症。结论：ICL V4c植入术矫正屈光不正具有良好的中远期临床效果。

Objective: To assess the medium-long term efffcacy, safety and stability of a newly developed posterior chamber phakic intraocular lens (model V4c Visian Implantable Collamer Lens) to correct refractive errors. Methods: Retrospective case series. This study evaluated eyes that had implantation of ICL V4c to correct ametropia for at least two years. Uncorrected and corrected distance visual acuities, refraction, contrast sensitivity, high-order aberration, quality of life, intraocular pressure, endothelial cell density, pIOL vault, and adverse events were evaluated to assess the efffcacy, safety and stability of V4c. Results: The study comprised 96 eyes of 50 patients. At 2 years postoperatively, the mean uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA) were 0.021±0.065 logMAR and 0.002±0.041 logMAR, which were better than preoperative CDVA. The efffcacy and safety indices were 1.05 and 1.09, respectively. The spherical equivalent was stable with improved contrast sensitivity and increased high-order aberrations, but the subjective visual quality was well. The IOP remained stable over time. The mean vault was (549.6±50.0) μm and the mean endothelial cell loss was 1.6%. No eye developed intraocular infection, secondary glaucoma, lens opacity, macular edema or retinal detachment.Conclusion: The good medium-long term outcomes support the use of ICL V4c for the correction of myopia. 

目的：观察和分析儿童眼科门诊就诊的屈光不正 3～7 岁患儿，有早产史和足月产史的患儿的屈光不正的特点和差异。

方法：屈光不正 179 例（358 眼），分为 2 组：早产史者 51 人，足月产者 128 人。1％阿托品眼膏散瞳进行视网膜带状光剪影验光。

结果：足月儿的屈光不正患儿中，以远视多见，占 157／256 眼（61.3％），对比有早产儿屈光不正的远视发病 25／102（24.5％），差异有统计学意义（P < 0.05）。有早产儿屈光不正中，以散光发病为主，占 81／102 眼（79.4％），尤以高度散光、混合散光多见，相对与足月儿，其散光发病，高度散光发病和混合散光发病眼数的差异均有显著性（P < 0.05）。

结论：散光，尤其是高度散光、复杂的混合散光是有早产儿童视力低下的重要原因。临床上散光与弱视的形成关系密切相关，因此不能忽略早产儿童视力发育，最早可提前到 2 岁即可进行屈光筛查。

Purpose: To observe the abnormal refractive state and clinical characteristics in preterm and full-term children of the Department of Pediatric Ophthalmology.

Methods: The ocular refraction status of 358 eyes in 51 preterm and 128 full-term children were checked by retinoscopy in dilated pupil after being used atropine eye drops.

Results: There were 157 eyes with hyperopia accounting for 61.3% in preterm children, and 25 eyes with hyperopia accounting for 24.5% in full-term children. The main type of refractive errors in preterm children is astigmatism, especially in high astigmatism and mixed astigmatism. The morbidity of astigmatism, hyper astigmatism, and mixed astigmatism in preterm children is higher than that in full-term children.

Conclusion: Astigmatism, especially high astigmatism and complex mixed astigmatism, are important reasons for low vision in preterm children. Clinically, there is a close relationship between astigmatism and amblyopia. Therefore, the visual development of preterm children should not be ignored, and refractive screening could be brought forward to two years old.

Background: Refractive errors are among the most frequent reasons for demand of eye-care services. Publications on refractive errors prevalence in our country are few. This study has the purpose to assess the prevalence of refractive errors in an adult population of Villa Maria, Córdoba, Argentina.

Methods: The Villa Maria Eye Study is a population-based cross-sectional study conducted in the city of Villa Maria, Córdoba, Argentina from May 2008 to November 2009. Subject’s aged 40+ received a demographic interview and complete ophthalmological exam. Visual acuity was obtained with an ETDRS chart. Cycloplegic auto refraction was performed. The spherical equivalent was highly correlated between right and left eyes, so only data of right eyes are presented. Myopia and hyperopia were defined with a ±0.50 diopters (D) criterion and astigmatism >1 D.

Results: This study included 646 subjects, aged 40 to 90 (mean age: 59.6±10.3 years old). Four hundred and sixty two (71.5%) were females. The mean spherical equivalent was +0.714±2.41 D (range, ?22.00 to +8.25 D) and the power of the cylinder was, on average, ?0.869±0.91 D (range, 0 to ?6.50 D). In this sample, 61.6% subjects were hyperopic, and 13.5% were myopic. Myopia prevalence was lower in men (9.8% versus 14.9%) but this difference among genders was not statistically significant. There were 141 subjects (21.8%) with anisometropia greater than 1 D, and 168 subjects (26.0%) with astigmatism greater than 1 D.

Conclusions: The present study shows the prevalence of cycloplegic refractive errors in an adult population of Argentina. The prevalence of hyperopia was high, while myopia prevalence was very low.

Background: Refractive errors are among the most frequent reasons for demand of eye-care services. Publications on refractive errors prevalence in our country are few. This study has the purpose to assess the prevalence of refractive errors in an adult population of Villa Maria, Córdoba, Argentina.

Methods: The Villa Maria Eye Study is a population-based cross-sectional study conducted in the city of Villa Maria, Córdoba, Argentina from May 2008 to November 2009. Subject’s aged 40+ received a demographic interview and complete ophthalmological exam. Visual acuity was obtained with an ETDRS chart. Cycloplegic auto refraction was performed. The spherical equivalent was highly correlated between right and left eyes, so only data of right eyes are presented. Myopia and hyperopia were defined with a ±0.50 diopters (D) criterion and astigmatism >1 D.

Results: This study included 646 subjects, aged 40 to 90 (mean age: 59.6±10.3 years old). Four hundred and sixty two (71.5%) were females. The mean spherical equivalent was +0.714±2.41 D (range, ?22.00 to +8.25 D) and the power of the cylinder was, on average, ?0.869±0.91 D (range, 0 to ?6.50 D). In this sample, 61.6% subjects were hyperopic, and 13.5% were myopic. Myopia prevalence was lower in men (9.8% versus 14.9%) but this difference among genders was not statistically significant. There were 141 subjects (21.8%) with anisometropia greater than 1 D, and 168 subjects (26.0%) with astigmatism greater than 1 D.

Conclusions: The present study shows the prevalence of cycloplegic refractive errors in an adult population of Argentina. The prevalence of hyperopia was high, while myopia prevalence was very low.

目的：观察后房型有晶体眼人工晶体(implantable collamer lens，ICL)V4c植入术后2年的有效性、安全性和稳定性，评估ICL V4c矫正屈光不正的中远期临床疗效。方法：回顾性病例研究。收集在河北省沧州市中心医院眼一科行ICL V4c手术治疗的屈光不正患者，观察并记录术前至术后2年的裸眼视力、最佳矫正视力、屈光状态、对比敏感度、高阶像差、眼压、人工晶体拱高、角膜内皮细胞计数、不良反应、主观视觉质量等临床资料，进行统计学分析。结果：完成随访的96例术眼，术后2年的平均裸眼视力(LogMAR)为0.021±0.065，平均最佳矫正视力(LogMAR)为0.002±0.041，优于术前最佳矫正视力，有效性指数为1.05，安全性指数为1.09，等效球镜数值稳定，对比敏感度提升，高阶像差有所增加，但主观视觉质量良好，眼压基本稳定，内皮细胞丢失率为1.6%，平均拱高为(549.6±50.0) μm，随访期间未发现眼内感染、继发性青光眼、晶状体混浊、黄斑水肿、视网膜脱离等并发症。结论：ICL V4c植入术矫正屈光不正具有良好的中远期临床效果。

Abstract Objective: To assess the medium-long term efficacy, safety and stability of a newly developed posterior chamber phakic intraocular lens (model V4c Visian Implantable Collamer Lens) to correct refractive errors. Methods: Retrospective case series. This study evaluated eyes that had implantation of ICL V4c to correct ametropia for at least two years. Uncorrected and corrected distance visual acuities, refraction, contrast sensitivity, high-order aberration, quality of life, intraocular pressure, endothelial cell density, pIOL vault, and adverse events were evaluated to assess the efficacy, safety and stability of V4c. Results: The study comprised 96 eyes of 50 patients. At 2 years postoperatively, the mean uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA) were 0.021±0.065 logMAR and 0.002±0.041 logMAR, which were better than preoperative CDVA. The efficacy and safety indices were 1.05 and 1.09, respectively. The spherical equivalent was stable withimproved contrast sensitivity and increased high-order aberrations, but the subjective visual quality was well. The IOP remained stable over time. The mean vault was (549.6±50.0) μm and the mean endothelial cell loss was 1.6%. No eye developed intraocular infection, secondary glaucoma, lens opacity, macular edema or retinal detachment. Conclusion: The good medium-long term outcomes support the use of ICL V4c for the correction of myopia.