AIM: To define the corneal hysteresis(CH), corneal resistance factor(CRF), Goldmann-correlated intraocular pressure(IOPg) and corneal compensated intraocular pressure(IOPcc) prior to and following coaxial micro-incisi...AIM: To define the corneal hysteresis(CH), corneal resistance factor(CRF), Goldmann-correlated intraocular pressure(IOPg) and corneal compensated intraocular pressure(IOPcc) prior to and following coaxial micro-incision phacoemulsification in patients with corneal astigmatism. METHODS: Of 97 patients with cataracts were enrolled in the study. Group 1 included patients with corneal astigmatism(K1-K2) values of K1-K2<+1.0 D, and group 2 with values of K1-K2 ≥+1.0 D and ≤+2.25 D. Coaxial micro-incision phacoemulsification of a corneal incision of 2.0 mm with intraocular lens(IOL) implantation was performed. CH, CRF, IOPg, IOPcc, waveform score(WS) were measured preoperatively and one week, one month postoperatively using an Ocular Response Analyzer. Axial length(AXL) was calculated by Tomey Optical Biometer OA 2000.RESULTS: Group 1 consisted of 51 patients with mean corneal astigmatism value of +0.49±0.25 D. Group 2 included 46 patients with astigmatism of +1.43±0.43 D. In group 1, CRF(t=2.68, P<0.05), CH(t=2.64, P<0.05) and WS(t=3.51, P<0.05) were significantly lower one week postoperatively, when compared to the preoperative values. CRF significantly decreased(t=3.61, P<0.05) when measured one month following the surgery. In group 2 CH(t=5.92, P<0.05), and WS(t=3.96, P<0.05) were significantly lowered one week after cataract surgery. Moreover, we observed a significant decrease in IOPg(t=2.24, P<0.05), CRF(t=5.05, P<0.05) and CH(t=2.31, P<0.05) one month after phacoemulsification. There was no statistically significant(t=-0.83, P=0.41) difference in AXL between study groups.CONCLUSION: CRF, CH and IOPg are reduced in patients with preoperative corneal astigmatism equal or higher than +1.0 D and lower than +2.25 D. Hence, bias of IOPg measurement in these patients may cause underestimation of the real IOP both before and after cataract surgery. The measurement of IOPcc allows the precise assessment of IOP pre-and postoperatively, independently on corneal astigmatism, CH and CRF values.展开更多
AIM：To determine the relevance of the objective parameters addressing the altered biomechanical properties of cornea for glaucoma monitoring in patients with mild or moderate thyroid associated orbitopathy（TAO）,and...AIM：To determine the relevance of the objective parameters addressing the altered biomechanical properties of cornea for glaucoma monitoring in patients with mild or moderate thyroid associated orbitopathy（TAO）,and in healthy individuals.· METHODS：Twenty-five patients with TAO（group 1）and 25 healthy adults（group 2） were included to the study.Both groups were of a similar age and the ratio women：man.For each patient,the following parameters of both eyes were measured with ocular response analyzer（ORA）：corneal hysteresis（CH）,corneal resistance factor（CRF）,Goldmann correlated intraocular pressure（IOPg） and corneal compensated intraocular pressure（IOPcc）.In both groups participating in our study,all measurements were performed within minutes to reduce the diurnal effects.· RESULTS：The mean age in group 1 was 56±11y and76%were women,24%were men.The mean age in group 2 was 64±11y and 68%were women,32%were men.CH correlated negatively with IOPg in group 1（r^2=0.10,P 〈0.05）.IOPg strongly correlated with IOPcc in both groups（group 1：r^2=0.79,P〈0.0001;group 2：r^2=0.85,P〈0.0001）.There was positive correlation between CRF and IOPg in group 1（r^2=0.12,P〈0.05） and in group 2（r^2=0.31,P〈0.0001）.Statistical analysis revealed no significant correlation between CRF and IOPcc in group 1（r^2=0.009,P 〉0.05） and also no significant correlation in group 2（r^2=0.04,P〉0.05）.CRF mean value in group 2（11.51±1.72 mm Hg） was higher than in group 1（10.85±1.45 mm Hg）（P〈0.05）.IOPg strongly correlated with IOPcc in both groups（group 1：r^2=0.79,P〈0.0001;group 2：r^2=0.85,P 〈0.0001）.There was also strong correlation between CRF and CH in both populations：group 1：（r^2=0.58,P〈0.0001）,group 2：（r^2=0.41,P 〈0.0001）.· CONCLUSION：Biomechanical parameters of cornea,as quantified by CH and CRF,and measured together with IOPcc,precisely reveal glaucoma staging in TAO and thus are reliable for diagnosing and follow-up in clinical practice. 〈/tr〉展开更多
Purpose: To investigate biomechanical properties of the cornea as measured using a Reichert ocular response analyzer (ORA) in a Taiwan Residents population. Methods: Basic demographic data were recorded for 1875 Taiwa...Purpose: To investigate biomechanical properties of the cornea as measured using a Reichert ocular response analyzer (ORA) in a Taiwan Residents population. Methods: Basic demographic data were recorded for 1875 Taiwan Residents subjects. Corneal hysteresis (CH), corneal resistance factor (CRF), central corneal thickness (CCT), Goldmann-equivalent intraocular pressure (IOPg), and corneal-compensated intraocular pressure (IOPcc) were measured with an ORA. Descriptive statistics and multiple regression analyses were used to assess and compare relevant factors of the CRF and CH. Results: In total, 1817 eyes were included in this study. The mean patient age was 21.4 ± 17.01 years. The mean (±SD) CH and CRF values were 10.6 ± 1.81 and 10.6 ± 1.99 mmHg, respectively. The mean CCT was 560.4 ± 38.53 μm. CH was correlated with IOPcc, CRF, and CCT. In the multiple linear-regression model, CH was associated with and affected by IOPcc, CRF, and CCT. In another multiple linear-regression model, CRF was associated with and affected by IOPcc, CH, and CCT. Conclusions: Measuring biomechanical properties by Reichert ORA, we found that CH and CRF values of a Taiwan Residents population were similar to those other Asian populations and other races. Our findings provided fundamental data of CH and CRF in a Taiwan Residents (ethic Chinese) and also Asian population.展开更多
Background:To evaluate,using a rabbit model,the influence of the wound healing process at the flap edge on corneal biomechanics after sutured,glued,and non-augmented microkeratome flaps.Methods:Unilateral 160μm thick...Background:To evaluate,using a rabbit model,the influence of the wound healing process at the flap edge on corneal biomechanics after sutured,glued,and non-augmented microkeratome flaps.Methods:Unilateral 160μm thick laser in situ keratomileusis(LASIK)flaps using a mechanical microkeratome were performed on the corneas of the left eyes of 36 rabbits.Animals were then divided into 3 groups of 12 rabbits each:A:the flaps were glued with human fibrin tissue adhesive(Tisseel);B:the flaps were sutured;and C:the flaps were allowed to heal without the use of sutures or glue(non-augmented).The contralateral eyes served as controls.Reichert ocular response analyzer(ORA)was used to measure corneal hysteresis(CH),corneal resistance factor(CRF),Goldmann-correlated intraocular pressure(IOPg)and cornea-compensated IOP(IOPcc)at 6 weeks and 3 months postoperatively.In vivo confocal microscopy(IVCM)was also used to study the corneal wound healing process in all groups.Results:Both mean CH and mean CRF were significantly higher in sutured and glued groups compared with the non-augmented group at 6 weeks and 3 months postoperatively(P<0.0001).No statistically significant difference in corneal biomechanics was found between controls and groups A and B at any time points.Activated keratocytes were detected at the wound edge and peripheral flap interface in sutured and glued groups.Conclusion:The healing process at the wound edge is critical for optimal corneal integrity.Fibrin glue may serve as a safe and effective substitute to sutures in enhancing the corneal flap edge healing response and in increasing its mechanical strength.展开更多
目的:探讨角膜中央与周边的厚度差异对角膜生物力学特性的影响。方法:回顾性系列病例研究。收集2006年10月至2007年10月在邯郸眼科医院测量的健康人群336例(336眼),来自邯郸眼科研究。运用Orbscan-II测量角膜中央厚度(CCT)、角膜最薄点(...目的:探讨角膜中央与周边的厚度差异对角膜生物力学特性的影响。方法:回顾性系列病例研究。收集2006年10月至2007年10月在邯郸眼科医院测量的健康人群336例(336眼),来自邯郸眼科研究。运用Orbscan-II测量角膜中央厚度(CCT)、角膜最薄点(TCP)以及3、4、5、6、7 mm处颞侧、上方、鼻侧及下方的角膜厚度;通过计算3、4、5、6、7 mm区域角膜厚度与中央厚度的比值,得到反映角膜中央与周边厚度差异的角膜厚度指数(CTI)。通过眼反应分析仪(ORA)测量角膜迟滞系数(CH)、角膜阻力因子(CRF);采用Pearson相关和Spearman相关分析CH、CRF与角膜厚度及年龄之间的相关性;采用独立样本t检验分析7 mm CTI总体分布中两端的最大5%与最小5%两组之间CH和CRF的差异。结果:研究对象4、5、6、7 mm角膜厚度与年龄均呈负相关(r=-0.15,P=0.003;r=-0.23,P<0.001;r=-0.33,P<0.001;r=-0.41,P<0.001),且随直径增大相关性逐渐增加;角膜最薄点、CCT及3 mm区域角膜厚度与年龄无相关性。5、6、7 mm CTI与年龄呈负相关(r=-0.18,P=0.001;r=-0.27,P<0.001;r=-0.27,P<0.001),3、4 mm CTI与年龄无相关性。CH与年龄无明显相关性,CRF与年龄呈负相关(r=-0.15,P=0.006)。CH与3、4、5、6 mm CTI呈负相关(r=-0.13,P=0.023;r=-0.14,P=0.010;r=-0.15,P=0.008;r=-0.13,P=0.019),CRF与3、4、5、6 mm CTI也呈负相关(r=-0.21,P<0.001;r=-0.24,P<0.001;r=-0.26,P<0.001;r=-0.16,P=0.005)。7 mm CTI位于总体分布中两端的最大5%与最小5%两组之间比较,CH和CRF差异有统计学意义(t=2.93,P=0.006;t=2.78,P=0.009)。结论:随年龄增加,健康人群CCT变化不大而周边厚度明显下降。CCT与周边厚度差异较大的角膜可能存在抵抗眼内压及外力作用能力下降的风险。展开更多
文摘AIM: To define the corneal hysteresis(CH), corneal resistance factor(CRF), Goldmann-correlated intraocular pressure(IOPg) and corneal compensated intraocular pressure(IOPcc) prior to and following coaxial micro-incision phacoemulsification in patients with corneal astigmatism. METHODS: Of 97 patients with cataracts were enrolled in the study. Group 1 included patients with corneal astigmatism(K1-K2) values of K1-K2<+1.0 D, and group 2 with values of K1-K2 ≥+1.0 D and ≤+2.25 D. Coaxial micro-incision phacoemulsification of a corneal incision of 2.0 mm with intraocular lens(IOL) implantation was performed. CH, CRF, IOPg, IOPcc, waveform score(WS) were measured preoperatively and one week, one month postoperatively using an Ocular Response Analyzer. Axial length(AXL) was calculated by Tomey Optical Biometer OA 2000.RESULTS: Group 1 consisted of 51 patients with mean corneal astigmatism value of +0.49±0.25 D. Group 2 included 46 patients with astigmatism of +1.43±0.43 D. In group 1, CRF(t=2.68, P<0.05), CH(t=2.64, P<0.05) and WS(t=3.51, P<0.05) were significantly lower one week postoperatively, when compared to the preoperative values. CRF significantly decreased(t=3.61, P<0.05) when measured one month following the surgery. In group 2 CH(t=5.92, P<0.05), and WS(t=3.96, P<0.05) were significantly lowered one week after cataract surgery. Moreover, we observed a significant decrease in IOPg(t=2.24, P<0.05), CRF(t=5.05, P<0.05) and CH(t=2.31, P<0.05) one month after phacoemulsification. There was no statistically significant(t=-0.83, P=0.41) difference in AXL between study groups.CONCLUSION: CRF, CH and IOPg are reduced in patients with preoperative corneal astigmatism equal or higher than +1.0 D and lower than +2.25 D. Hence, bias of IOPg measurement in these patients may cause underestimation of the real IOP both before and after cataract surgery. The measurement of IOPcc allows the precise assessment of IOP pre-and postoperatively, independently on corneal astigmatism, CH and CRF values.
文摘AIM：To determine the relevance of the objective parameters addressing the altered biomechanical properties of cornea for glaucoma monitoring in patients with mild or moderate thyroid associated orbitopathy（TAO）,and in healthy individuals.· METHODS：Twenty-five patients with TAO（group 1）and 25 healthy adults（group 2） were included to the study.Both groups were of a similar age and the ratio women：man.For each patient,the following parameters of both eyes were measured with ocular response analyzer（ORA）：corneal hysteresis（CH）,corneal resistance factor（CRF）,Goldmann correlated intraocular pressure（IOPg） and corneal compensated intraocular pressure（IOPcc）.In both groups participating in our study,all measurements were performed within minutes to reduce the diurnal effects.· RESULTS：The mean age in group 1 was 56±11y and76%were women,24%were men.The mean age in group 2 was 64±11y and 68%were women,32%were men.CH correlated negatively with IOPg in group 1（r^2=0.10,P 〈0.05）.IOPg strongly correlated with IOPcc in both groups（group 1：r^2=0.79,P〈0.0001;group 2：r^2=0.85,P〈0.0001）.There was positive correlation between CRF and IOPg in group 1（r^2=0.12,P〈0.05） and in group 2（r^2=0.31,P〈0.0001）.Statistical analysis revealed no significant correlation between CRF and IOPcc in group 1（r^2=0.009,P 〉0.05） and also no significant correlation in group 2（r^2=0.04,P〉0.05）.CRF mean value in group 2（11.51±1.72 mm Hg） was higher than in group 1（10.85±1.45 mm Hg）（P〈0.05）.IOPg strongly correlated with IOPcc in both groups（group 1：r^2=0.79,P〈0.0001;group 2：r^2=0.85,P 〈0.0001）.There was also strong correlation between CRF and CH in both populations：group 1：（r^2=0.58,P〈0.0001）,group 2：（r^2=0.41,P 〈0.0001）.· CONCLUSION：Biomechanical parameters of cornea,as quantified by CH and CRF,and measured together with IOPcc,precisely reveal glaucoma staging in TAO and thus are reliable for diagnosing and follow-up in clinical practice. 〈/tr〉
文摘Purpose: To investigate biomechanical properties of the cornea as measured using a Reichert ocular response analyzer (ORA) in a Taiwan Residents population. Methods: Basic demographic data were recorded for 1875 Taiwan Residents subjects. Corneal hysteresis (CH), corneal resistance factor (CRF), central corneal thickness (CCT), Goldmann-equivalent intraocular pressure (IOPg), and corneal-compensated intraocular pressure (IOPcc) were measured with an ORA. Descriptive statistics and multiple regression analyses were used to assess and compare relevant factors of the CRF and CH. Results: In total, 1817 eyes were included in this study. The mean patient age was 21.4 ± 17.01 years. The mean (±SD) CH and CRF values were 10.6 ± 1.81 and 10.6 ± 1.99 mmHg, respectively. The mean CCT was 560.4 ± 38.53 μm. CH was correlated with IOPcc, CRF, and CCT. In the multiple linear-regression model, CH was associated with and affected by IOPcc, CRF, and CCT. In another multiple linear-regression model, CRF was associated with and affected by IOPcc, CH, and CCT. Conclusions: Measuring biomechanical properties by Reichert ORA, we found that CH and CRF values of a Taiwan Residents population were similar to those other Asian populations and other races. Our findings provided fundamental data of CH and CRF in a Taiwan Residents (ethic Chinese) and also Asian population.
文摘Background:To evaluate,using a rabbit model,the influence of the wound healing process at the flap edge on corneal biomechanics after sutured,glued,and non-augmented microkeratome flaps.Methods:Unilateral 160μm thick laser in situ keratomileusis(LASIK)flaps using a mechanical microkeratome were performed on the corneas of the left eyes of 36 rabbits.Animals were then divided into 3 groups of 12 rabbits each:A:the flaps were glued with human fibrin tissue adhesive(Tisseel);B:the flaps were sutured;and C:the flaps were allowed to heal without the use of sutures or glue(non-augmented).The contralateral eyes served as controls.Reichert ocular response analyzer(ORA)was used to measure corneal hysteresis(CH),corneal resistance factor(CRF),Goldmann-correlated intraocular pressure(IOPg)and cornea-compensated IOP(IOPcc)at 6 weeks and 3 months postoperatively.In vivo confocal microscopy(IVCM)was also used to study the corneal wound healing process in all groups.Results:Both mean CH and mean CRF were significantly higher in sutured and glued groups compared with the non-augmented group at 6 weeks and 3 months postoperatively(P<0.0001).No statistically significant difference in corneal biomechanics was found between controls and groups A and B at any time points.Activated keratocytes were detected at the wound edge and peripheral flap interface in sutured and glued groups.Conclusion:The healing process at the wound edge is critical for optimal corneal integrity.Fibrin glue may serve as a safe and effective substitute to sutures in enhancing the corneal flap edge healing response and in increasing its mechanical strength.
文摘目的:探讨角膜中央与周边的厚度差异对角膜生物力学特性的影响。方法:回顾性系列病例研究。收集2006年10月至2007年10月在邯郸眼科医院测量的健康人群336例(336眼),来自邯郸眼科研究。运用Orbscan-II测量角膜中央厚度(CCT)、角膜最薄点(TCP)以及3、4、5、6、7 mm处颞侧、上方、鼻侧及下方的角膜厚度;通过计算3、4、5、6、7 mm区域角膜厚度与中央厚度的比值,得到反映角膜中央与周边厚度差异的角膜厚度指数(CTI)。通过眼反应分析仪(ORA)测量角膜迟滞系数(CH)、角膜阻力因子(CRF);采用Pearson相关和Spearman相关分析CH、CRF与角膜厚度及年龄之间的相关性;采用独立样本t检验分析7 mm CTI总体分布中两端的最大5%与最小5%两组之间CH和CRF的差异。结果:研究对象4、5、6、7 mm角膜厚度与年龄均呈负相关(r=-0.15,P=0.003;r=-0.23,P<0.001;r=-0.33,P<0.001;r=-0.41,P<0.001),且随直径增大相关性逐渐增加;角膜最薄点、CCT及3 mm区域角膜厚度与年龄无相关性。5、6、7 mm CTI与年龄呈负相关(r=-0.18,P=0.001;r=-0.27,P<0.001;r=-0.27,P<0.001),3、4 mm CTI与年龄无相关性。CH与年龄无明显相关性,CRF与年龄呈负相关(r=-0.15,P=0.006)。CH与3、4、5、6 mm CTI呈负相关(r=-0.13,P=0.023;r=-0.14,P=0.010;r=-0.15,P=0.008;r=-0.13,P=0.019),CRF与3、4、5、6 mm CTI也呈负相关(r=-0.21,P<0.001;r=-0.24,P<0.001;r=-0.26,P<0.001;r=-0.16,P=0.005)。7 mm CTI位于总体分布中两端的最大5%与最小5%两组之间比较,CH和CRF差异有统计学意义(t=2.93,P=0.006;t=2.78,P=0.009)。结论:随年龄增加,健康人群CCT变化不大而周边厚度明显下降。CCT与周边厚度差异较大的角膜可能存在抵抗眼内压及外力作用能力下降的风险。
