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1.
目的:比较儿童进展性近视眼与正视眼的调节功能特征,探讨调节对近视的潜在影响。方法:病例对照研究。选择2015年12月至2016年5月于温州医科大学附属眼视光医院就诊的68例儿童,进展性近视组[(等效球镜度(SE)≤-0.75 D)]与正视组(+0.50 D≥SE≥-0.50 D)各34例,测量内容包括主观调节幅度、远距调节灵活度及调节刺激-反应曲线(ASRC)。采用独立样本t检验比较2组间调节功能的差异。结果:正视组、进展性近视组SE分别为(0.18±0.28)D、(-2.88±1.03)D,差异有统计学意义(t=-16.72,P<0.001)。进展性近视组的主观调节幅度低于正视组(t=-2.22,P=0.03)。2组间的远距调节灵活度与ASRC斜率差异均无统计学意义(t=-0.82,P=0.41;t=1.58,P=0.12)。进展性近视组和正视组在0~6 D调节刺激范围的调节滞后面积分别为(7.35±1.54)D2 、(6.48±1.05)D2 (t= 2.74,P=0.01);且在不同调节刺激水平下(1、2、3、4、5 D),进展性近视比正视眼的调节滞后量大(t=2.40、2.78、2.79、2.49、2.12,P<0.05)。而进展性近视组在6 D刺激水平的调节滞后量比正视组稍高,但差异无统计意义(t=1.83,P=0.07)。结论:儿童进展性近视眼的调节反应特征与正视眼不完全一致,其中进展性近视眼的调节滞后量高于正视眼,提示调节滞后可能在近视发生中具有一定的作用。  相似文献   

2.
目的:探讨7~18岁青少年角膜生物力学及校正眼压与屈光状态的内在关系。方法:横断面研究。 选择2017年11月至2018年2月于中山大学中山眼科中心屈光门诊就诊的中国青少年325例,年龄7~18 岁,等效球镜度(SE)-10.25~+16.50 D。采用IOLMaster测量眼轴长度(AL),Corvis ST测量角膜生 物力学参数及生物力学校正眼压(bIOP),Pentacam测量眼前节生物学参数。按照右眼SE将受检者 分为高度近视、中低度近视、正视和远视组。采用Pearson或Spearman相关分析SE与角膜生物力学 参数的相关性。用协方差分析比较4组的角膜生物力学参数差异,用方差分析比较4组间的bIOP差异。 结果:SE越偏向近视,第二次压平速率(VA2,r=0.180,P=0.001)越快,峰值距离(PD,r=-0.273, P<0.001)和形变幅度(DA,r=-0.167,P=0.002)越大。AL越长,PD(r=0.355,P<0.001)越大,VA2 (r=-0.138,P=0.021)越快。4组间PD(F=9.372,P<0.001)、DA(F=4.425,P=0.005)和VA2(F=4.961, P=0.002)的总体差异有统计学意义,进一步比较发现,PD、DA和VA2绝对值在高度近视、中低度 近视、正视、远视组间依次下降,差异均有统计学意义(均P<0.05)。高度近视组(102.04±19.59)和 中低度近视组(98.95±16.62)的角膜硬度参数(SP-A1)差异无统计学意义,但中低度近视组比正视 组(107.49±18.66,P=0.010)和远视组(108.98±20.20,P=0.004)的SP-A1低,差异有统计学意义。 眼压(IOP)和bIOP均与SE无相关性。结论:7~18岁青少年SE越偏向近视,角膜硬度越低。无论是 否校正角膜生物力学因素的影响,眼压均与屈光度无关。  相似文献   

3.
目的使用双通道视觉质量分析系统(OQAS)分析手机阅读对大学生泪膜及调节力的影响,并分析屈光度与泪膜及调节力的关系。方法前瞻性自身对照研究。使用OQAS分别检测并比较53例在校大学生(共106眼)手机阅读1 h前后的泪膜稳定性(OSI值 )及调节力。指标前后对照采用配对t检验,成组比较采用独立样本t检验,多组间比较采用方差分析。结果手机阅读1 h后泪膜稳定性及调节力均发生了改变,OSI值升高(泪膜稳定性变差)(t=-7.464,P<0.01),调节力下降(t=4.881,P<0.01),差异有统计学意义;手机阅读前后泪膜的改变无性别差异(t=-1.207,P>0.05),调节力的改变无性别差异(t=1.216,P>0.05);手机阅读前正视组、低度近视组、中重度近视组之间OSI值表现出正视组<低度近视组<中高度近视组,但是差异无统计学意义,但3组之间调节力的差异有统计学意义(F=3.349,P<0.05),且正视组>低度近视组和中高度近视组;手机阅读1 h后,随着等效球镜度的增加,泪膜更加不稳定,调节幅度变小,但是不同屈光状态的3组之间OSI值及调节改变量的差异均无统计学意义。结论手机阅读会使泪膜稳定性变差,调节幅度变小,并且与近视程度有关。  相似文献   

4.
目的 探讨近视青少年正、负相对调节力与正视青少年正、负相对调节力的差异,分析正、负相对调节力变化与近视发病的关系。方法 横断面研究。少年组:正视组43例(+0.50~-0.25 D),年龄7~16岁,平均(10.7±3.0)岁;近视组110例(-0.50~-3.00 D,屈光参差<-1.00 D),年龄7~16岁,平均(11.5±2.6)岁。青年组(由大学生组成):大学入校新生266例,平均年龄(18.8±0.8)岁,其中正视29例,近视237例。被检者在电脑验光基础上,使用综合验光仪进行主觉验光,并在综合验光仪上测双眼正、负相对调节力。数据采用单因素方差分析。结果 少年组:正视组正相对调节力的均值为(-5.52±1.21)D,近视组为(-2.27±1.19)D,差异有统计学意义(F=227.26,P<0.01)。正视组与近视组负相对调节力分别为(+2.41±0.65)D、(+2.21±0.73)D,差异无统计学意义。正视组正、负相对调节力的比值为2.35±0.45,而近视组比值为1.10±0.60,差异有统计学意义(F=156.40,P<0.01)。青年组:正视组正相对调节力均值为(-4.87±1.47)D,近视眼组为(-2.63±1.41)D,差异有统计学意义(F=66.62,P<0.01)。正视组负相对调节力为(+2.09±0.46)D,近视组为(+1.98±0.48)D,差异无统计学意义。正视组正、负相对调节力比值为2.35±0.51,而近视眼组为1.34±0.93,差异有统计学意义(F=47.28,P<0.01)。结论 近视青少年比同龄正视者正相对调节力明显下降,正、负相对调节力比值下降。正相对调节力下降是青少年近视眼发病的临床特征之一。  相似文献   

5.
康龙丹  谢姝  邢骥  王闯  周爽  刘岩 《国际眼科杂志》2011,11(10):1746-1748
目的:分析在校大学生不同屈光状态与调节幅度、立体视的关系。方法:对入选的150名在校大学生行客观验光、综合验光及相关双眼视功能的检查,包括立体视、调节幅度等的测量。按是否有近视分为:(1)正视组(11名),+0.75D≤SE(等效球镜度数)<-0.50D;(2)近视组(139名),SE≥-0.5D。近视组中按近视的度数分为:低度近视组(51名),中度近视组(69名),高度近视组(19名)。按是否有屈光参差分为:非屈光参差组(123名),屈光参差组(27名)。分析研究不同屈光状态学生的调节幅度、立体视的状况以及屈光参差对立体视的影响。结果:近视组的调节幅度较正视组的调节幅度大,差异有统计学意义(t=1.16,P<0.05),近视组间调节幅度值有差异(F=1.474,P<0.05),其中高度近视组与低度近视组、中度近视组之间差异有统计学意义(P<0.05),近视度数越大,测得的调节幅度值越大(r=0.2698,P<0.05);正视组与近视组之间立体视无显著差异(χ2=0.325,P>0.05),低、中、高度近视组之间立体视无显著差异(χ2=0.16,P>0.05);屈光参差组的立体视功能比非屈光参差组差,差异有统计学意义(Fisher,P<0.05)。结论:近视组较正视组的调节幅度大,近视组中,调节幅度与近视的度数呈正相关性。屈光参差组较非屈光参差组的立体视功能差。  相似文献   

6.
观察0.01%阿托品对青少年近视调节参数的影响。方法:前瞻性非随机对照研究。选取2015年 4月至2018年6月于聊城市第二人民医院眼科就诊的轻中度近视患者61例(122眼),年龄13~16 (14.4±0.9)岁,根据监护人意愿分为2组:阿托品组30例(60眼),滴用0.01%阿托品滴眼液1次;对照组31例(62眼),滴用玻璃酸钠滴眼液1次。阿托品组在用药前及用药后2、4、6 h行近视力、调节幅度和调节灵敏度检查。对照组在用药前及用药后2、6 h行近视力、调节幅度和调节灵敏度检查。采用重复测量方差分析、t检验对数据进行统计学分析。结果:点眼药前后,2组间近视力差异无统计学意义(F=0.209,P=0.650),各时间点近视力比较差异无统计学意义(F=0.292,P=0.594),组别与时间无交互作用(F=0.097,P=0.756)。阿托品组用药后2 h调节幅度低于对照组(t=-13.09, P<0.001),2 组间用药后6 h调节幅度差异无统计学意义(t=-0.26,P=0.797);阿托品组用药后 2 h调节幅度[(10.09±0.69)D]较用药前[(12.58±0.88)D]下降(P<0.001),用药后4 h调节幅度(10.98±0.77)D较用药后2 h升高(P<0.001),用药后6 h调节幅度(12.45±0.77)D和用药前相比,差异无统计学意义(P=0.911)。阿托品组用药后2、6 h的调节灵敏度与对照组比较,差异均无统计学意义;阿托品组各时间点调节灵敏度比较差异无统计学意义(F=0.09,P=0.965)。结论:0.01%阿托品滴眼液滴眼部1次后,调节幅度下降,但剩余的调节力足够,不影响近视力和调节灵敏度。  相似文献   

7.
目的:探讨近视性屈光参差患者双眼间调节力差异与屈光参差程度间的关系。方法:横断面研究。收集2019年11月至2021年6月在山东第一医科大学附属青岛眼科医院就诊的近视患者123例(246眼),年龄8~21岁。根据双眼间等效球镜度(SE)差值分为屈光不正组(SE差值≤0.25D)29例、低度屈光参差组(1.00D≤SE差值<2.50D)62例及高度屈光参差组(SE差值≥2.50D)32例3组。所有患者符合双眼最佳矫正视力(BCVA)≥0.8且各项原始数据较为完善。使用综合验光仪测量3组患者的单眼调节幅度(AMP)、单、双眼负相对调节(NRA)、正相对调节(PRA)、调节反应(AR)及调节灵活度(AF)在睫状肌麻痹下验光后确定双眼间屈光度数,分析3组间双眼调节相关参数及单眼调节参数差差值(双眼间调节参数差值=近视屈光度较高眼调节数值-近视屈光度较低眼调节数值)之间的差异。对3组间调节参数比较采用单因素方差分析;对屈光参差程度与双眼调节参数值及双眼间调节参数差值间的关系分析选择Spearman相关分析。结果:3组间双眼NRA、PRA、AR、AF值及单眼间NRA、AF差值比较差异均无统计学意义。3组AR差值分别为-0.03±0.25、0.20±0.30、0.26±0.36,差异有统计学意义(F=7.36,P<0.001);3组PRA差值分别为0.04±0.27、0.34±0.72、0.66±0.63,差异有统计学意义(W=7.47,P<0.001);3组AMP差值分别为0.41±0.86、-1.07±1.53、-1.02±2.18,差异有统计学意义(W=9.25,P<0.001)。事后多重比较显示,屈光不正组与低度屈光参差组和高度屈光参差的AR差值、PRA差值、AMP差值比较差异均有统计学意义(均P<0.05)。相关性分析显示,SE差值与AR差值、AMP差值存在低强度的正相关性(r=0.22,P=0.014;r=0.36,P<0.001)。结论:不同程度近视性屈光参差患者双眼间调节参数差值不同,且双眼间AR差值、AMP差值与双眼间屈光度差异程度存在一定相关性。  相似文献   

8.
目的:探讨青少年儿童近视屈光度与眼轴长度(AL)、中央角膜厚度(CCT)、眼压(IOP)、角膜曲率(CC)及中心凹下脉络膜厚度(CT)之间的关系,为青少年儿童近视的防治提供依据。方法:系列病例研究。选取2016 年3-12 月在山西省眼科医院就诊的青少年儿童近视患者。散瞳验光测量屈光度并测量CCT、IOP、AL、CC及CT等数据。依据等效球镜度(SE)分为低、中、高度近视组,分析屈光度与CCT、IOP、AL、CC及中心凹下CT的关系。组间数据比较采用方差分析,变量间的相关性 分析采用Pearson相关分析。结果:共纳入青少年儿童近视患者80例(158眼),年龄(7.9±2.4)岁。低、中、高度近视组SE分别为(-2.28±0.85)D、(-4.43±0.82)D、(-8.51±1.50)D。低、中、高度近视组AL分别为(24.0±0.7)mm、(25.0±0.6)mm、(26.6±1.5)mm,3组间总体差异有统计学意义(F=55.03,P < 0.001),中心凹下CT分别为(280±82)μm、(207±63)μm、(184±72)μm,3 组间总体差异有统计学意义(F=12.64,P < 0.001)。各组间CCT、IOP、CC差异均无统计学意义。屈光度的绝对值与AL呈正相关性(r =0.858,P < 0.001),与CT呈负相关性(r =-0.590,P < 0.001)。CT与AL、CCT呈负相关性(r =-0.567,P < 0.001;r =-0.300,P=0.007),余指标间无相关性。结论:随青少年儿童近视屈光度增加,AL增加,中心凹下CT厚度的减小,而屈光度与CCT、IOP、CC的关系不明确。  相似文献   

9.
目的比较中国近视儿童配戴单光框架眼镜(SV)、角膜塑形镜、RGPCL以及渐变多焦点眼镜(PAL)2年后眼轴及屈光度变化,评估不同矫正方式对儿童近视的控制效果。方法前瞻性非随机临床对照研究。104例近视儿童入选,年龄9~15岁,近视度-0.50~-4.50 D,散光低于-2.00 D,分别选择SV(21例)、角膜塑形镜(24例)、RGPCL(30例)和PAL(29例)作为矫正方式,随访2年,进行睫状肌麻痹验光、Zeiss IOLMaster测量眼轴、Medmont E300角膜地形图测量角膜形态等检查。采用单因素方差分析、卡方检验、重复测量方差分析对数据进行检验。结果戴镜前,4组的年龄、角膜曲率值、眼轴长度差异均无统计学意义,等效球镜度差异有统计学意义(F=6.920,P<0.01),其中RGPCL组等效球镜度均值为(-3.04±0.79)D,高于其他3组。2年后,各组眼轴均有明显增长(F=315.912,P<0.01),SV组、角膜塑形镜组、RGPCL组和PAL组分别增长了(0.57±0.23)mm、(0.31±0.20)mm、(0.51±0.30)mm和(0.61±0.27)mm。4组眼轴的增长量在随访时间与不同矫正方式间的交互作用、不同矫正方式间差异均有统计学意义(F1=4.175,F2=6.599,P均<0.01),角膜塑形镜组眼轴增长量最小,SV、RGPCL、PAL 3组间差异无统计学意义。SV、RGPCL、PAL组近视度随着时间均有增长(F=121.840,P<0.01),分别增长了(-1.23±0.64)D,(-0.82±0.69)D和(-1.12±0.53)D。3组的屈光度增高量在随访时间与不同矫正方式间的交互作用、不同矫正方式间差异均无统计学意义(F1=1.300,F2=2.987,P均>0.05)。结论临床常用的4种矫正方式SV、PAL、RGPCL及角膜塑形镜对儿童近视的控制及延缓作用以角膜塑形镜效果最佳,其他三者之间无差异。  相似文献   

10.
目的:观察飞秒激光小切口角膜基质透镜取出术(SMILE)矫正低、中、高度近视术后1 年的临床疗效。方法:回顾性系列病例研究。收集2014 年12 月至2015 年9 月于中国人民解放军武汉总医院眼科行SMILE并完成1 年随访的近视患者86 例(141 眼)病历资料,按照术前等效球镜度(SE)分为3 组:低度近视组:-0.50 D相似文献   

11.
This paper investigates the amplitude of accommodation of early onset myopes, late onset myopes, emmetropes, and hyperopes. Eighty subjects were used, 41 women and 39 men, with an age range of 18-22 yr (mean = 19.82). All subjects wore an optimum refractive correction, giving visual acuities of 20/20 or better. Significant differences were found between the four refractive groups, with late onset myopes having the largest amplitude of accommodation, followed by early onset myopes, emmetropes, and hyperopes. The results are discussed in the light of previous findings on tonic accommodation and the accommodative response gradient and interpretated in the context of a dual innervation to the ciliary muscle.  相似文献   

12.
Dynamics of accommodative facility in myopes   总被引:1,自引:0,他引:1  
PURPOSE: To evaluate the dynamic changes in refraction during the accommodative facility test in myopes and emmetropes. METHODS: Ten myopes and 10 emmetropes participated in the study. All were young adults, and refractive error in the myopes was corrected with soft contact lenses. Monocular accommodative facility measurements were taken for a 40-cm and a 6-m working distance with +2.00/-2.00-D and Plano/-2.00-D flippers, respectively. Subjective facility was recorded with automated flippers and objective measurements of dynamic accommodation response were simultaneously taken with a photorefractor. RESULTS: Subjective and objective facility measurements showed a significantly lower facility rate in myopes when compared with emmetropes at distance (P < 0.05) but not at near (P > 0.05). The response amplitude of accommodation during facility tasks was found to be similar in the two refractive groups. However, the velocity of accommodation was found to be lower in myopes than in emmetropes for distance facility (P < 0.05) but not for near facility (P > 0.05). Velocity of disaccommodation was lower in myopes than in emmetropes at both distance and near (P < 0.05). CONCLUSIONS: During distance accommodative facility testing, myopes exhibited a lower velocity of accommodation and disaccommodation, which led to a lower distance accommodative facility rate. For near facility measurements, however, although velocity of disaccommodation was lower in myopes, velocity of accommodation was found to be similar in the two refractive groups. A variety of factors that contribute to these differences are discussed.  相似文献   

13.
目的 探讨发病早期的儿童和青少年近视的调节功能状态,分析主导眼和非主导眼的调节功能水平.方法 应用动态检影法和移近法分别测量50例发病1~2年的学龄期儿童和青少年近视患儿调节滞后和调节幅度;同样方法测量20例正视儿童和25例远视屈光不正患儿;检测其主导眼和非主导眼.结果 近视患儿的主导眼和非主导眼的调节幅度和调节滞后与正视儿童均差异无统计学意义;而其主导眼和非主导眼的调节幅度比远视患儿明显更大(t=2.21,P=0.03<0.05;t=2.83,P=0.006<0.05);两组的调节滞后差异无统计学意义.50例近视患儿主导眼和非主导眼的调节滞后值分别为(0.73±0.31)D和(0.81±0.38)D,主导眼和非主导眼间差异有统计学意义(t=2.14,P=0.038<0.05);调节幅度分别为(13.39±3.51)D和(13.26±3.60)D,差异无统计学意义.95例观察对象(近视、正视和远视患儿)的主导眼的调节滞后度为(0.68±0.36)D,非主导眼调节滞后度为(0.75±0.34)D,主导眼和非主导眼间的差异有统计学意义(t=2.06,P=0.042<0.05);主导眼调节幅度(12.9±3.09)D,非主导眼为(12.6±3.09)D,差异无统计学意义(t=1.49,P=0.14).结论 发病早期的儿童和青少年近视的调节滞后值和调节幅度与正视儿童无明显差别;调节幅度比远视儿童的更大.儿童和青少年主导眼的调节滞后比非主导眼的更小,进行调节滞后相关研究时应注意主导眼和非主导眼的区别.  相似文献   

14.
目的 探讨进展性近视、稳定性近视及正视之间反应性AC/A值的关系,并对其成因进行分析.方法 病例对照研究.门诊选取10~22岁病例,根据随访资料以及主觉验光结果分为进展性近视组、稳定性近视组以及正视组各17例,在全矫基础上分别测量9个调节刺激水平下的调节反应以及隐斜值,计算调节误差指数(AEI)和反应性AC/A值.数据采用单因素方差分析.结果 3组屈光组的反应性AC/A值之间的差异有统计学意义(F=4.051,P<O.05),进展性近视组的AC/A值高于稳定性近视组和正视组.3组的AEI值之间无显著性差异(F=2.579,P>0.05);在高调节刺激水平(3.21~4.12 D),进展性近视组显示出较大的内隐斜,但只有在4.12 D水平,3组之间的差异具有统计学意义(F=3.828,P<0.05).结论 和稳定性近视以及正视相比,进展性近视具有较高的AC/A值和较大的近距内隐斜,提示较大的近距内隐斜可能是高AC/A的成因,高AC/A值和较大的近距内隐斜可能是近视进展的危险因素.  相似文献   

15.
目的探讨准分子激光原位角膜磨镶术(LASIK)对近视患者眼调节状态的影响,同时对眼调节状态的变化与视疲劳症状的关系进行探讨。方法回顾性研究。选取2009年3月至8月来东风总医院眼科行LASIK的双眼近视患者60例(120眼),年龄18-35岁,术前等效球镜值为(-5.52±1.60)D,散光度〈2.00D.最佳矫正视力(BCVA)≥1.0。选择正视者20例(40眼)作为对照组。术前及术后1周、2周、1个月,分别对两组测定其单眼及双眼调节幅度,并对其进行近距工作视疲劳症状的问卷调查。采用独立样本t检验对两组的调节幅度和视疲劳评分进行比较,对近视组各时间点的调节幅度行单因素方差分析.并对术后1周调节幅度下降程度与术前屈光度的关系采用Pearson相关分析。结果①调节状态:LASIK术后第1周,近视组单眼及双眼调节幅度分别为(7.82±0.58)D和(8.10±0.54)D,较术前下降(P均〈0.05),之后逐渐恢复,至术后1个月时超过术前水平,且与正视组相比差异无统计学意义。②视疲劳症状:LASIK术后第1周,近视患者视疲劳症状均较术前明显加重,之后症状逐渐减轻,至术后1个月时视疲劳症状较术前明显减轻。③相关性分析:术后1周时,调节幅度的降低程度与术前屈光度呈正相关(r=0.83,P〈0.01);近视组视疲劳症状与双眼调节幅度呈负相关(r=-0.79,P〈0.01)。结论LASIK术后患者视近时调节需求增加,且单眼及双眼调节幅度均有短暂下降,术后第1周显著下降,之后逐渐恢复。LASIK术后视疲劳症状和眼调节状态的变化有关。  相似文献   

16.
Dynamic accommodation and myopia.   总被引:6,自引:0,他引:6  
PURPOSE: Accommodative effort during nearwork is thought to be a causative factor in the development of myopia. It has been proposed that an anomaly in autonomic control may be a precursor to the development of myopia. In the present study the closed-loop accommodation response after variations in fixation period was investigated in emmetropes, early-onset myopes and late-onset myopes to determine characteristics of reflex accommodation for each refractive group. METHODS: Closed-loop accommodation responses were measured in a group of emmetropes (n = 7), early-onset myopes (n = 7), and late-onset myopes (n = 7) by use of a dynamic tracking infrared optometer. A variation in fixation period (10 seconds, 60 seconds, and 180 seconds) before an accommodative step was used to stimulate the accommodation control mechanism differentially. RESULTS: Group results of accommodative response times showed that late-onset myopes were significantly affected by the duration of fixation before the change in stimulus vergence. Accommodative response times after 3 minutes of sustained near vision were significantly longer than those observed for other groups for the near-to-far condition. Reaction time appears to be independent of refractive grouping, prior fixation period, and direction of step change. CONCLUSIONS: Late-onset myopes showed significantly extended accommodation response times after a sustained near vision task that was demonstrable under well-controlled experimental conditions. The extended response times observed in the present study were consistent with previous reports of refractive shifts in late-onset myopes and early-onset myopes and provide a corollary between reflex and adaptive components of the accommodation response. Potential mechanisms are discussed in an attempt to explain the resultant hysteresis under closed-loop viewing conditions.  相似文献   

17.
Synkinesis of accommodation and vergence in late-onset myopia   总被引:1,自引:0,他引:1  
The accommodative response (AR) to disparity-vergence and blur stimuli was determined for 45 subjects; 15 emmetropes, 15 late-onset myopes (LOM's), and 15 early-onset myopes (EOM's). The accommodative response was measured at approximately 1-s intervals for 50 s using an objective infrared optometer. Disparity-driven accommodation was induced by a 4 delta base-out prism at accommodative stimulus levels of 2.50 and 3.25 D. LOM's show significantly higher levels of disparity-induced accommodation when compared with the other two refractive groups. Blur-induced accommodation was produced by increasing the accommodative stimulus from 2.50 to 3.25 D with no concomitant change in vergence stimulus. EOM's exhibit less blur-induced accommodation compared with LOM's and emmetropes. These results are discussed with reference to differences in accommodation-vergence synkinesis between LOM's and EOM's, and in relation to the etiology of late-onset myopia.  相似文献   

18.
目的研究快速序列视觉呈现方式(rapid serial visual presentation.RSVP)阅读状态下进展性近视、稳定性近视和正视之间调节反应的差异,探讨调节因素在近视发生、发展过程中的表达。方法45例受试者参加本实验,分为进展性近视、稳定性近视和正视组,各15例。阅读材料为位于距受试者左眼角膜平面25cm处的电脑显示屏上的一篇中文短文.通过RSVP软件呈现单个字符.字体大小为9pt,文字呈现速度为150字/min。使用SEIKO—WV500自动验光仪测量其开放视野阅读状态下左眼的调节反应。结果所有受试者在4D的调节刺激下,均存在一定程度的调节滞后,个体差异较大。进展性近视组的调节反应低于正视组[(2.32±0.43)0VS(3.19±0.53)0,P〈0.01],进展性近视组的调节反应亦低于稳定性近视组[(2.32±0.43)0VS(3.07±0.34)D,P〈0.01],而正视组和稳定性近视组差异无显著性(P=0.441)。结论近距离阅读状态下进展性近视有较高的调节滞后,远视性离焦造成的模糊斑可能是近视的发生发展的促成因素,随着近视发展的稳定.调节反应恢复至一般水平。  相似文献   

19.
L Yan  L Huibin  L Xuemin 《Eye (London, England)》2014,28(11):1334-1340

Purpose

To investigate the changes of intraocular pressure (IOP) and anterior eye segment biometric parameters under different accommodative statuses in progressing myopes and emmetropes.

Methods

Forty-six progressing myopes and 40 emmetropes participated in this study. All the subjects had their IOP and anterior eye segment biometric parameters (including corneal thickness, anterior chamber depth, anterior chamber angle width, and lens thickness) measured using iCare rebound tonometer and VisanteTM anterior segment-optical coherence tomography while accommodative stimuli of 0, 3, and 6D were presented.

Results

There was no significant difference in IOP between progressing myopes and emmetropes when no accommodation was induced (16.22±4.11 vs 17.01±3.72, respectively, t=−0.93, P>0.05). However, IOP significantly increased with accommodation in progressing myopes (mean change +1.02±2.07 mm Hg from 0D to 6D, F=5.35, P<0.01), but remained unchanged (mean change −0.76±3.22 mm Hg from 0D to 6D, F=1.46, P>0.05) in emmetropes. Meanwhile, we found that their anterior chamber depth decreased (P<0.01), anterior chamber angle narrowed (P<0.01), and lens thickened (P<0.01) significantly with accommodation, both in progressing myopes and emmetropes.

Conclusions

Although no difference was detected between the IOPs of progressing myopes and emmetropes without accommodation, accommodation could induce transient IOP elevation in progressing myopes. Simultaneously, we found that their anterior chamber depth decreased, anterior chamber angle narrowed, and lens thickened with accommodation. Although emmetropes showed the similar anterior eye segment structure changes, their IOPs did not increase with accommodation. Our study indicated that IOP elevation with accommodation in progressing myopes might be related to myopia progression.  相似文献   

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