AIM： To analyse ocular biomechanical properties, central corneal thickness （CCT） and intraocular pressure （lOP） in post-keratoplasty eyes, as compared to normal subjects, with a new Scheimpflug-based technology. ...AIM： To analyse ocular biomechanical properties, central corneal thickness （CCT） and intraocular pressure （lOP） in post-keratoplasty eyes, as compared to normal subjects, with a new Scheimpflug-based technology. Moreover, biomechanical data were correlated with the size and age of the donor and recipient corneas. METHODS： Measurements were conducted on 46 eyes of 46 healthy patients without any corneal pathology （age： 53.83 ±20.8y） and 30 eyes of 28 patients after penetrating keratoplasty （age： 49.43 ±21.34y）. Ten biomechanical parameters, the CCT and lOP were recorded by corneal visualization Scheimpflug technology （CorVis ST） using high-speed Scheimpflug imaging. Keratometry values were also recorded using Pentacam HR system. Scheimpflug measurements were performed after 43.41± 40.17mo （range： 11-128mo） after the keratoplasty and after 7.64±2.34mo （range： 5-14mo） of suture removal. RESULTS： Regarding the device-specific biomechanical parameters, the highest concavity time and radius values showed a significant decrease between these two groups （P=0.01 and P 〈0.001）. None of other biomechanical parameters disclosed a significant difference. The CCT showed a significant difference between post keratoplasty eyes as compared to normal subjects （P= 0.003） using the CorVis ST device. The lOP was within the normal range in both groups （P=0.84）. There were no significant relationships between the keratometric data, the size of the donor and recipient, age of the donor and recipient and biomechanical properties obtained by CorVis ST. CONCLUSION： The ocular biomechanics remain stable after penetrating keratoplasty according to the CorVis ST measurements. Only two from the ten device-specific parameters have importance in the follow-up period after penetrating keratoplasty.展开更多
The examination of the effects of second generation lotra filcon B silicone hydrogel(SiH)lenses on the cornea when worn for three years of daily wear.Material and Methods:55 healthy patients were divided into two grou...The examination of the effects of second generation lotra filcon B silicone hydrogel(SiH)lenses on the cornea when worn for three years of daily wear.Material and Methods:55 healthy patients were divided into two groups:current hydrogel contact lens wearers refitted with lotrafilcon B lenses(Group 1;28 patients)and neophyte contact lens wearers(Group 2;27 patients).Each patient's subjective eye comfort was measured with a self-administered questionnaire.The corneas were analyzed using contact specular microscope to measure corneal thickness and the endothelium before the SiH lenses werefitted after four weeks,one month,six months,one year,two years,and three years of lens wear.Results:Subjective complaints of patients in Group 1 were reduced;however patients in Group 2 experienced discomfort during the first two to four weeks of use.In Group 1,objective examinations identified a decrease in endothelial cell density.In Group 2,the endothelial cell density increased slightly in the first two years but decreased after three years.The results indicate that lotra filcon B slows down the deleterious effects of contact lenses.The coe±cient of variation significantly decreased after six months in Group 1(0.47 vs 0.44;p?0:049),whereas,in Group 2,the hexagonal cells improved significantly after one month(27.78 vs 28.25;p=0.025).Conclusion:Based on the subjects involved and the period of time under examination,it can be concluded that high-Dk SiH lenses support the physiological metabolism and functions of the cornea by improving oxygen provision.展开更多
文摘AIM： To analyse ocular biomechanical properties, central corneal thickness （CCT） and intraocular pressure （lOP） in post-keratoplasty eyes, as compared to normal subjects, with a new Scheimpflug-based technology. Moreover, biomechanical data were correlated with the size and age of the donor and recipient corneas. METHODS： Measurements were conducted on 46 eyes of 46 healthy patients without any corneal pathology （age： 53.83 ±20.8y） and 30 eyes of 28 patients after penetrating keratoplasty （age： 49.43 ±21.34y）. Ten biomechanical parameters, the CCT and lOP were recorded by corneal visualization Scheimpflug technology （CorVis ST） using high-speed Scheimpflug imaging. Keratometry values were also recorded using Pentacam HR system. Scheimpflug measurements were performed after 43.41± 40.17mo （range： 11-128mo） after the keratoplasty and after 7.64±2.34mo （range： 5-14mo） of suture removal. RESULTS： Regarding the device-specific biomechanical parameters, the highest concavity time and radius values showed a significant decrease between these two groups （P=0.01 and P 〈0.001）. None of other biomechanical parameters disclosed a significant difference. The CCT showed a significant difference between post keratoplasty eyes as compared to normal subjects （P= 0.003） using the CorVis ST device. The lOP was within the normal range in both groups （P=0.84）. There were no significant relationships between the keratometric data, the size of the donor and recipient, age of the donor and recipient and biomechanical properties obtained by CorVis ST. CONCLUSION： The ocular biomechanics remain stable after penetrating keratoplasty according to the CorVis ST measurements. Only two from the ten device-specific parameters have importance in the follow-up period after penetrating keratoplasty.
文摘The examination of the effects of second generation lotra filcon B silicone hydrogel(SiH)lenses on the cornea when worn for three years of daily wear.Material and Methods:55 healthy patients were divided into two groups:current hydrogel contact lens wearers refitted with lotrafilcon B lenses(Group 1;28 patients)and neophyte contact lens wearers(Group 2;27 patients).Each patient's subjective eye comfort was measured with a self-administered questionnaire.The corneas were analyzed using contact specular microscope to measure corneal thickness and the endothelium before the SiH lenses werefitted after four weeks,one month,six months,one year,two years,and three years of lens wear.Results:Subjective complaints of patients in Group 1 were reduced;however patients in Group 2 experienced discomfort during the first two to four weeks of use.In Group 1,objective examinations identified a decrease in endothelial cell density.In Group 2,the endothelial cell density increased slightly in the first two years but decreased after three years.The results indicate that lotra filcon B slows down the deleterious effects of contact lenses.The coe±cient of variation significantly decreased after six months in Group 1(0.47 vs 0.44;p?0:049),whereas,in Group 2,the hexagonal cells improved significantly after one month(27.78 vs 28.25;p=0.025).Conclusion:Based on the subjects involved and the period of time under examination,it can be concluded that high-Dk SiH lenses support the physiological metabolism and functions of the cornea by improving oxygen provision.
