Effect of Watching 3-Dimensional Television on Refractive Error in Children

Purpose

To investigate the effect of watching 3-dimensional (3D) television (TV) on refractive error in children.

Methods

Sixty healthy volunteers, aged 6 to 12 years, without any ocular abnormalities other than refractive error were recruited for this study. They watched 3D TV for 50 minutes at a viewing distance of 2.8 meters. The image disparity of the 3D contents was from -1 to 1 degree. Refractive errors were measured both before and immediately after watching TV and were rechecked after a 10-minute rest period. The refractive errors before and after watching TV were compared. The amount of refractive change was also compared between myopes and controls. The refractive error of the participants who showed a myopic shift immediately after watching TV were compared across each time point to assure that the myopic shift persisted after a 10-minute rest.

Results

The mean age of the participants was 9.23 ± 1.75 years. The baseline manifest refractive error was -1.70 ± 1.79 (-5.50 to +1.25) diopters. The refractive errors immediately after watching and after a 10-minute rest were -1.75 ± 1.85 and -1.69 ± 1.80 diopters, respectively, which were not different from the baseline values. Myopic participants (34 participants), whose spherical equivalent was worse than -0.75 diopters, also did not show any significant refractive change after watching 3D TV. A myopic shift was observed in 31 participants with a mean score of 0.29 ± 0.23 diopters, which resolved after a 10-minute rest.

Conclusions

Watching properly made 3D content on a 3D TV for 50 minutes with a 10-minute intermission at more than 2.8 meters of viewing distance did not affect the refractive error of children.     

三种不同设备行屈光手术时的角膜切削误差比较

目的调查2种不同的准分子激光设备和1种全飞秒激光手术设备用于准分子激光原位角膜磨镶术（LASIK）时对中央角膜厚度切削误差的影响,探索角膜切削误差的变化规律。方法前瞻性病例对照研究。使用A型超声角膜测厚仪测量分别应用3种不同设备行手术治疗的138例（274眼）患者术前及术后1个月的中央角膜厚度。其中51例（100眼）使用Esiris机器行LASIK手术（Esiris—LASIK）,50例（100眼）使用VisxS4-IR机器行LASIK手术（Visx—LASIK组）,37例（74眼）使用VisuMax机器行SMILE手术（VisuMax—SMILE组）。所有眼按屈光度分为低、中、高度3组,分别计算中央角膜厚度及角膜切削误差,并分析切削误差与不同设备、近视程度、散光程度、角膜切削直径及手术前角膜厚度的关系。采用单样本t检验、双因素方差分析及Pearson相关进行数据分析。结果3组病例中,近视程度、术前中央角膜厚度及术前散光度对角膜切削误差均没有显著影响,设备或手术方式对角膜切削误差有显著的影响。在Esiris—LASIK组中,角膜的实际切削厚度小于预期切削厚度,差异有统计学意义（低度近视组,t=4．672,P〈0．01;中度近视组,t=10．629,P〈0．01;高度近视组,t=11．021,P〈0．01）;Visx—LASIK组中,角膜的实际切削厚度大于预期切削厚度,差异有统计学意义（低度近视组,t=3．910,P〈O．01;中度近视组,t=4．922,P〈0．01;高度近视组,t=4．807,P〈0．01）;在VisuMax—SMILE组中,角膜的实际切削厚度与预期切削厚度差异无统计学意义（中度近视组,t=1．158,P〉O．05;高度近视组,t=0．836,P〉0．05）。结论不同的手术设备会显著影响屈光手术中中央角膜厚度的切削误差。     

近视眼中央角膜厚度和最薄角膜厚度的关系

目的 研究近视患者中央角膜厚度和最薄角膜厚度的大小、位置关系,以及近视程度对角膜厚度的影响.方法 回顾性病例对照研究.以接受近视性屈光手术的150例(300眼)为研究对象,根据等效球镜分为低、中、高近视3组,提取他们的术前Pentacam检查资料.左右眼参数的相关性和差异分别采用Pearson相关分析和配对t检验,多组比较采用方差分析,同一侧眼不同参数差异采用独立样本t检验.结果 左眼平均中央角膜厚度和最薄角膜厚度分别为(555.83±31.83)μm和(552.88±31.48)μm,右眼平均中央角膜厚度和最薄角膜厚度分别为(554.10±31.47) μm和(549.26±31.25)μm.左眼角膜最薄点72.00％(108/150)位于颞下方;右眼角膜最薄点70.67％(106/150)位于颞下方.不同程度近视组间的角膜厚度差异无统计学意义.结论 最薄角膜厚度与中央角膜厚度并不一致,双眼角膜最薄点均主要位于颞下方,其次在鼻下方.角膜厚度与近视程度无关.     

The Correlation between Angle Kappa and Ocular Biometry in Koreans

Purpose

To investigate normative angle kappa data and to examine whether correlations exist between angle kappa and ocular biometric measurements (e.g., refractive error, axial length) and demographic features in Koreans.

Methods

Data from 436 eyes (213 males and 223 females) were analyzed in this study. The angle kappa was measured using Orbscan II. We used ocular biometric measurements, including refractive spherical equivalent, interpupillary distance and axial length, to investigate the correlations between angle kappa and ocular biometry. The IOL Master ver. 5.02 was used to obtain axial length.

Results

The mean patient age was 57.5 ± 12.0 years in males and 59.4 ± 12.4 years in females (p = 0.11). Angle kappa averaged 4.70 ± 2.70 degrees in men and 4.89 ± 2.14 degrees in women (p = 0.48). Axial length and spherical equivalent were correlated with angle kappa (r = -0.342 and r = 0.197, respectively). The correlation between axial length and spherical equivalent had a negative correlation (r = -0.540, p < 0.001).

Conclusions

Angle kappa increased with spherical equivalent and age. Thus, careful manipulation should be considered in older and hyperopic patients when planning refractive or strabismus surgery.     

Refractive Errors in Koreans: The Korea National Health and Nutrition Examination Survey 2008-2012

PurposeOur study provides epidemiologic data on the prevalence of refractive errors in all age group ≥5 years in Korea.MethodsIn 2008 to 2012, a total of 33,355 participants aged ≥5 years underwent ophthalmologic examinations. Using the right eye, myopia was defined as a spherical equivalent (SE) less than -0.5 or -1.0 diopters (D) in subjects aged 19 years and older or as an SE less than -0.75 or -1.25 D in subjects aged 5 to 18 years according to non-cycloplegic refraction. Other refractive errors were defined as follows: high myopia as an SE less than -6.0 D; hyperopia as an SE larger than +0.5 D; and astigmatism as a cylindrical error less than -1.0 D. The prevalence and risk factors of myopia were evaluated.ResultsPrevalence rates with a 95% confidence interval were determined for myopia (SE <-0.5 D, 51.9% [51.2 to 52.7]; SE <-1.0 D, 39.6% [38.8 to 40.3]), high myopia (5.0% [4.7 to 5.3]), hyperopia (13.4% [12.9 to 13.9]), and astigmatism (31.2% [30.5 to 32.0]). The prevalence of myopia demonstrated a nonlinear distribution with the highest peak between the ages of 19 and 29 years. The prevalence of hyperopia decreased with age in subjects aged 39 years or younger and then increased with age in subjects aged 40 years or older. The prevalence of astigmatism gradually increased with age. Education was associated with all refractive errors; myopia was more prevalent and hyperopia and astigmatism were less prevalent in the highly educated groups.ConclusionsIn young generations, the prevalence of myopia in Korea was much higher compared to the white or black populations in Western countries and is consistent with the high prevalence found in most other Asian countries. The overall prevalence of hyperopia was much lower compared to that of the white Western population. Age and education level were significant predictive factors associated with all kinds of refractive errors.     

不同类型青光眼患者前部巩膜厚度与中央角膜厚度和眼轴长度的相关性分析

背景 巩膜厚度与青光眼关系密切,不同类型青光眼的临床特点不同,其巩膜厚度可能存在一定差异,但目前的相关研究结果有一定争议. 目的 研究各种类型的青光眼患者前部巩膜厚度(AST)、中央角膜厚度(CCT)和眼轴长度间的关系.方法 采用回顾性描述性研究设计.纳入2009年3月至2010年11月就诊于北京大学第一医院眼科门诊的连续患者160例,其中原发性开角型青光眼(POAG) 34例34眼、正常眼压性青光眼(NTG) 37例37眼、原发性闭角型青光眼(PACG) 35例35眼及高眼压症(OHT) 17例17眼,对照组为早期白内障患者37例37眼.分别采用超声角膜测厚仪、眼部A型超声测量仪测量各组患者的CCT、AST及眼轴长度,采用超声生物显微镜(UBM)测量系统测量颞侧巩膜突后2 mm处的巩膜厚度.采用协方差分析法和SNK-q检验对各组的测量参数进行比较,用Pearson积矩相关分析和线性回归法对上述各组患者AST、CCT及眼轴长度间的关系进行分析. 结果 PACG组、POAG组、NTG组及OHT组的CCT值分别为(535.54±5.20)、(550.47±5.28)、(521.61±5.07)和(575.75±7.76) μm,对照组为(535.06±5.06) μm,5个组间的总体差异有统计学意义(F=9.560,P=0.000),其中OHT组的CCT值较其他各组均增加,差异均有统计学意义(均P=0.000),POAG组的CCT值较PACG、NTG及对照组均增加(P=0.046、0.000、0.040),NTG组及PACG组与对照组间CCT值的差异均无统计学意义(P=0.950、0.060).PACG组、POAG组、NTG组及OHT组AST值分别为(0.593±0.050)、(0.600±0.050)、(0.592士0.060)、(0.610±0.060) mm,对照组为(0.604±0.060) mm,5个组间AST的差异无统计学意义(F=0.700,P=0.590).PACG组的眼轴长度短于其他各组,差异均有统计学意义(均P=0.000).POAG组和NTG组患者的CCT与AST呈正相关(POAG:r=0.445,P=0.008;NTG:r=0.400,P=0.014). 结论 不同类型青光眼患者的CCT不同,AST无明显不同;POAG患者及NTG患者的CCT与AST变化间可能存在一定的正相关.     

Assessment of Risk Factors Affecting Refractive Outcomes after Phacovitrectomy for Epiretinal Membrane

PurposeTo investigate factors associated with refractive outcomes after phacovitrectomy for epiretinal membrane (ERM).MethodsRetrospective review of patients undergoing phacovitrectomy for ERM was done. The main outcome measure was predictive refraction error (PE), defined as observed refraction error – target refraction error, calculated by the SRK/T, Haigis, and SRK II formulae. PE was measured at postoperative 1, 3, and 6 months. Simple and multiple linear regression analysis were used to evaluate factors associated with PE.ResultsA total of 53 eyes of 53 patients were included. The mean PEs at postoperative 1, 3, and 6 months were all negative, implying myopic shift in all patients regardless of the intraocular lens formula used. Haigis formula showed the least myopic shift among the three formulae (p = 0.001, Friedman test). There was no significant difference in PE depending on preoperative central macular thickness (CMT) in subgroup analysis. On stepwise multiple linear regression analysis, ERM etiology (β = 0.759, p = 0.004, SRK/T formula; β = 0.733, p = 0.008, Haigis formula; β = 0.933, p < 0.001, SRK II formula), preoperative anterior chamber depth (β = −0.662, p = 0.013, Haigis formula; β = −0.747, p = 0.003, SRK II formula), and decrease of CMT (β = −0.003, p = 0.025, SRK/T formula) were significantly associated with PE at postoperative 6 months.ConclusionsMyopic shift in PE was observed after combined phacovitrectomy for epiretinal membrane. ERM etiology, preoperative anterior chamber depth, and decrease of CMT were significantly associated with PE at postoperative 6 months. There was no difference in PE after surgery between the two groups defined by CMT (≥500 and <500 μm).     

Refractive Error in School Children in an Urban and Rural Setting in Cambodia

Purpose: To assess the prevalence of refractive error in schoolchildren aged 12–14 years in urban and rural settings in Cambodia’s Phnom Penh and Kandal provinces.

Methods: Ten schools from Phnom Penh Province and 26 schools from Kandal Province were randomly selected and surveyed in October 2010. Children were examined by teams of Australian and Cambodian optometrists, ophthalmic nurses and ophthalmologists who performed visual acuity (VA) testing and cycloplegic refraction.

Results: A total of 5527 children were included in the study. The prevalence of uncorrected, presenting and best-corrected VA ≤ 6/12 in the better eye were 2.48% (95% confidence interval [CI] 2.02–2.83%), 1.90% (95% CI 1.52–2.24%) and 0.36% (95% CI 0.20–0.52%), respectively; 43 children presented with glasses whilst a total of 315 glasses were dispensed. The total prevalence of refractive error was 6.57% (95% CI 5.91–7.22%), but there was a significant difference between urban (13.7%, 95% CI 12.2–15.2%) and rural (2.5%, 95% CI 2.03–3.07%) schools (P?<?0.0001). Refractive error accounted for 91.2% of visually impaired eyes, cataract for 1.7%, and other causes for 7.1%. Myopia (spherical equivalent ≤ ?0.50 diopters [D] in either eye) was associated with increased age, female gender and urban schooling.

Conclusions: The prevalence of refractive error was significantly higher in urban Phnom Penh schools than rural schools in Kandal Province. The prevalence of refractive error, particularly myopia was relatively low compared to previous reports in Asia. The majority of children did not have appropriate correction with spectacles, highlighting the need for more effective screening and optical intervention.     

小学生眼球生物学参数和近视危险因素调查研究

目的对比2009年和2010年不同年级小学生眼球生物学参数的变化,比较眼轴长度与角膜曲率半径比值（AL／CR）大于3的人数在不同年级中所占比例的差异。方法前瞻性调查研究。选择2009年北京市羊坊店学区全部小学的一、四年级学生,跟踪检测2年。采用标准对数视力表检测远视力,采用IOLMaster测量眼球生物学参数。取右眼测量值进行分析。对数据进行独立样本t检验、配对t检验及卡方检验。结果2009年检测小学生2970例,一年级组1282例,年龄（6．44±0．52）岁;四年级组1688例,年龄（9．25±0．46）岁。2010年检测小学生2179例,2个年级分别为1210例【年龄（7．44±0．51）岁】和969例[年龄（10．25±0．48）岁]。这2个年级组学生在1年内,远视力变差（t=-15．54、-10．50,P〈0．01）,眼轴变长（t=24．21、25．84,P〈0．01）,眼轴／角膜曲率半径（AL／CR）变大（t=11．58、9．77,P〈0．01）,差异均有统计学意义：角膜屈光力、角膜散光和角膜曲率半径的差异无统计学意义。同一年级组内的女生与男生相比,都具有较短的眼轴、较小的角膜曲率半径和较小的角膜屈光力（P均〈0．01）,视力和其他眼球生物学参数表现出部分差异。四年级组2009年和2010年AL／CR〉3人数的比例高于一年级组（x^2=489．7、319．9,P〈0．01）。2010年2个年级组AL／CR〉3人数的比例高于2009年（X^2=140．2、40．1,P〈0．01）。结论小学生的视力和眼球生物学参数随年龄增长而改变。年龄越大,存在近视患病危险因素的人数比例越大,近视患病的危险性也相应增加。分析AL／CR〉3人数的比例作为评估群体近视患病危险性的筛查指标可以在以后的研究中推广。     

LASIK角膜瓣厚度与中央角膜曲率的关系

目的探讨平均角膜中央曲率与所制角膜瓣厚度之间的关系。方法对19例(38只眼)近视患者术前行眼前节分析仪及A超仪检查测得中央角膜曲率及中央角膜厚度,采用HANSTOME 160μm微型角膜板层刀、直径8.5cm吸附环,制作角膜瓣后,掀开角膜瓣,测量基质床中央角膜厚度,即得到所制角膜瓣厚度,所有患者手术先做右眼后做左眼。结果中央区最大角膜曲率(K_1)均值为44.3875D,中央区最小角膜曲率(K_2)为43.225D,角膜中央厚度为(529±16.1)μm,角膜瓣厚度为：右眼(112.33±8.2)μm,左眼(100.889±3.1)μm,平均角膜基质床厚度：右眼(402.5±12.1)μm,左眼(415.22±14.7)μm。平均中央角膜曲率、角膜中央厚度分别与角膜瓣厚度值经统计学处理,均P＞0.05,而右眼与左眼角膜瓣厚度差,P＜0.05,右眼角膜瓣厚度大于左眼。结论平均中央角膜曲率与角膜瓣厚度之间无相关。右眼与左眼的角膜瓣厚度之间均有差异性,提示中央角膜曲率不是影响角膜瓣厚度的因素;左眼中央角膜厚度比右眼厚时可考虑先行左眼角膜瓣的制作,以尽可能保留更多的角膜基质床。     

角膜塑形镜治疗青少年中度近视的临床观察

目的观察夜戴型角膜塑形镜治疗青少年中度近视的临床疗效,以及戴镜1年后屈光度、角膜厚度和眼轴的变化。方法前瞻性临床研究。9～15岁的中度近视青少年患者87例（174眼）,平均等效球镜度为（-4.13±0.74）D;37例配戴角膜塑形镜,戴镜前和戴镜后1周、1个月、3个月、6个月、1年随访裸眼视力、角膜曲率;测量并比较1年后等效球镜度、角膜厚度及眼轴的变化。50例配戴框架眼镜,测量并比较1年后等效球镜度、眼轴的变化。对相关数据进行重复测量的方差分析和独立样本t检验。结果角膜塑形镜组戴镜1年后停戴1个月等效球镜度为（-4.69±0.57）D;框架眼镜组戴镜1年后为（-4.72±0.80）D,塑形镜组和框架组1年等效球镜度分别增加（0.31±0.21）D、（0.77-0.46）D,两者比较差异有统计学意义（t=30.109,P〈0.01）;眼轴增加分别为（0.11±0.26）mm、（0.26±0.60）mm,两者比较差异有统计学意义（t=18.565,P〈0.01）。角膜塑形镜组戴镜前与1年后角膜厚度无差异。结论角膜塑形镜治疗青少年中度近视效果确切;与框架眼镜相比,可明显减少近视增长,有效控制眼轴变长,一定程度上可以控制近视发展。     

眼前节相干光断层成像在LASIK术前角膜厚度测量的应用观察

目的探讨眼前节相干光断层成像(OCT)在LASIK术前角膜厚度测量的精确性。方法分别采用眼前节OCT、超声及光学方法对LASIK术前患者的角膜厚度进行测量,将结果进行对照分析。结果眼前节OCT在LASIK术前角膜厚度测量的结果与超声同样准确,经统计学分析无差异性。结论眼前节OCT可作为LASIK手术前角膜厚度测量的依据,并可作为术后分析观察的方法。     

Relationship between Myopia and Optical Components - A Study among Chinese Hong Kong Student Population

Purpose: To establish the prevalence and severity of myopia among the Chinese Hong Kong students and to study the relationship between myopia and optical components.Methods;One thousand and seventy-five freshmen of the 1993-1994 academic year in the Chinese University of Hong Kong underwent the eye examination including evaluation of refractive error, keratometry, and A-scan ultrasonic biometry. The data were analyzed with the SPSS/PC 4. 01 statistical package. Results: The prevalence of myopia was 91. 7% with the mean refraction being -4. 00 ± 2. 64D in this young adult population. The statistical analyses demonstrated a significant correlation between refractive value and axial length of the globe (r=-0. 78), vitreous length (r=-0. 76), anterior chamber depth (r=-0. 33), lens thickness (r = 0. 13) and corneal curvature (r = 0. 19). Conclusion: The refractive status is mainly dependent on the axial length. In general, the higher the myopia was, the longer the eyeball, the deeper the anterior chamber,     

近视眼角膜厚度与眼压相关因素分析

目的 探讨近视眼角膜中央厚度(CCT)、屈光度、角膜曲率、年龄、性别与眼压(IOP)测量值之间的关系.方法 对219例431只眼用超声角膜测厚仪、Goldmann眼压计、检影镜及电脑验光仪和ObscanⅡ角膜地形图分别测量其数据.结果 近视眼患者CCT与IOP之间具有直线正相关性,CCT每增加10μm,眼压值约增加0.5 mmHg(1 mmHg=0.133 kPa).近视患者CCT与屈光度数具有负相关性.近视患者CCT与角膜曲率、年龄及性别不相关.结论 CCT为影响IOP测量的一个重要因素,检查CCT有助于更好的了解真实IOP值;CCT随近视眼患者屈光度数的增加有变薄的趋势.     

Prediction of Refractive Error in Combined Vitrectomy and Cataract Surgery With One-Piece Acrylic Intraocular Lens

Purpose

To compare the predicted and actual refractive errors of hydrophilic, one-piece, C-flex®570C (C-flex) intraocular lens (IOL) implantation in simultaneous vitrectomy and lens extraction in various conditions.

Methods

One hundred fifty-nine eyes of patients who had lens extraction between March 2004 and September 2005 were enrolled in a retrospective study. Group 1 had lens extraction and IOL implantation, and Group 2 had lens extraction and IOL implantation with vitrectomy. IOL calculation was done with axial length and keratometry measurements. The actual and predicted refractive errors were compared at 1 and 6 months postoperatively. The factors influencing the postoperative refractive outcomes were analyzed.

Results

The mean refractive predictive error (i.e., the actual minus predicted spherical equivalent) was +0.19±0.39 D (Diopter) and -0.26±0.45 D at 1 and 6 months postoperatively (all: p<0.001) in group 1, and -0.22±0.39 D and -0.06±0.62 D at 1 and 6 months postoperatively (p=0.013, p=0.399 respectively). In group 2, all surgical factors related to refractive errors were not statistically significant (all: p>0.05).

Conclusions

Refractive errors in combined surgery showed myopic shift of -0.50 D and -0.32 D at 1 and 6 months postoperatively compared with C-flex IOL implantation alone. With the hyperopic tendency of IOL and myopic tendency of vitrectomy, the combined surgery made postoperative refractive errors near emmetropia.     

先天性上睑下垂的屈光状态及弱视情况

目的了解先天性上睑下垂患者的屈光状态、弱视等情况,分析其与屈光不正及弱视的关系。方法回顾性病例研究。对北京同仁医院眼科门诊确诊为先天性上睑下垂的患者187例（242眼）进行详尽的病史收集及眼科检查。筛选患者初诊年龄为（7.4±2.2）岁。根据上睑下垂的程度分为轻度、中度及重度。利用χ2检验及t检验分析患者的屈光不正及弱视状况,并比较不同程度上睑下垂患者之间的屈光状态和弱视差异。结果242只上睑下垂眼中,近视、远视及散光的所占比例分别为16.9%、62.8%和31.1%。弱视的所占比例为29.8%,其中,重度先天性上睑下垂眼弱视的所占比例要高于轻中度者（57.8% vs. 41.2%,χ2=4.046,P<0.05）。结论先天性上睑下垂患者的屈光不正及弱视发生率均高于无上睑下垂人群的发生率。重度上睑下垂患者有较高的弱视发生率。     

Relationship Between Corneal Hysteresis and Corneal Resistance Factor with Other Ocular Parameters

Abstract

Purpose: To evaluate the relationship between corneal hysteresis (CH) and corneal resistance factor (CRF) with age, central corneal thickness (CCT), corneal curvature (KM), corneal volume (CV), and refractive error in naïve eyes. Methods: 105 healthy subjects (58 male and 47 female) were included in this study. The ages ranged from 19 to 82 years (mean 43.1?±?15.4 years) and refraction between ?11?D and +6?D (mean ?0.79?±?2.95?D). CH and CRF obtained with the Ocular Response Analyzer (ORA) were correlated with age, refractive error, Goldmann Applanation Tonometry (GAT), and with CCT, KM, CV obtained with the Pentacam, and with Corneal-Compensated Intraocular Pressure (IOPcc) and Goldmann-correlated intraocular pressure measurement (IOPg) obtained with ORA. A multivariable mixed effect model was used to evaluate associations among these parameters. Results: CH ranged from 6.9 to 14.6?mmHg (mean 10.26?±?1.49?mmHg); CRF ranged from 5.8 to 17?mmHg (mean 10.38?±?1.64?mmHg). Multivariate analysis showed a statistically significant correlation between CH with CCT (p?<?0.001), and KM (p?<?0.001), and between CRF with CCT (p?<?0.001) and GAT (p?<?0.001). Conclusions: Our findings support the hypothesis that CH and CRF are related to the corneal shape and thickness, and show a decrease of CH with age.     

眼轴与角膜曲率半径比值定性评估青少年儿童近视的准确性

目的评价眼轴与平均角膜曲率半径比值（简称轴率比）诊断青少年儿童近视的准确性。方法横断面研究。根据纳入标准,连续选取2012年12月至2014年9月期间,在上海儿童医学中心眼科门诊首诊的3~17岁屈光不正青少年儿童共1 011例。检查记录患儿双眼裸眼视力、眼轴、平均角膜曲率半径等,计算轴率比（AL/CR）。双眼睫状肌麻痹后视网膜检影及主觉验光,记录主觉验光的等效球镜度（SE）。以SE≤-0.50 D为近视诊断标准,AL/CR>3为可疑近视。数据行正态性检验、秩相关分析及ROC曲线分析等处理。结果AL/CR和SE均非正态分布,AL/CR为3.05（2.27,3.54）,SE为-1.25 D（-11.38 D,+11.63 D）,AL/CR与SE呈负相关（r=-0.563,P<0.01）,与诊断近视的金标准睫状肌麻痹下主觉验光相比,AL/CR诊断近视的灵敏度为0.896,特异度为0.918,准确度为90.3%,Kappa系数为0.790,ROC曲线下面积为0.965（P<0.01）。结论轴率比>3对近视的定性诊断价值较高。     

夜戴和日戴Ortho-K CL对眼部的影响

目的　观察过夜配戴和日间配戴Ortho-KCL后对眼部的影响。方法　55名配戴新型Ortho-KCL(Nu-vision,HDS材料)近视患者中,过夜戴镜(OW)74只眼(近视＜5.25D,散光＜1.25D,Ⅰ组),日间戴镜(DW)36只眼(近视＞5.00D,散光＜1.75D,Ⅱ组)。观察戴镜前及戴镜后1个月、2个月、3个月及6个月的角膜中心厚度及周边部厚度的变化;A超测定眼轴长、前房深、晶体厚及玻璃体腔长度的变化;角膜内皮细胞的改变,非接触眼压测定值的变化以及有无角结膜的其它合并症。结果　角膜中心厚度均减薄,周边部均增厚,2个月时变化最显著,之后有所恢复。Ⅰ组周边部厚度变化比较显著。Ⅱ组变化值约为Ⅰ组的1/2。Ⅱ组眼轴长度及玻璃体腔长度明显大于Ⅰ组,两组戴镜后两长度有轻度缩短。Ⅰ组戴镜6个月后角膜内皮细胞密度显著降低,平均细胞面积及CV值显著增大,六角形细胞比率显著降低,Ⅱ组仅CV值增大。非接触眼压测定值两组戴镜后均较前降低,Ⅰ组有显著性改变,3个月后达最低值,然后逐渐回升,6个月后,接近戴镜前眼压值。戴镜期间,无角膜新生血管,角膜浸润,角膜感染等严重合并症出现。结论　Ortho-KCL的日间戴镜方式比过夜戴镜方式对眼的影响小,安全性相对较高。需长期利用Ortho-KCL控制和治疗近视的青少年患者应考虑适时调整戴镜方式与时间并及时更换镜片,以保证治疗的有效性和安全性。