AIM: To quantify the changes in the lens profile with accommodation in different age groups. METHODS: The Pentacam HR system was used to obtain the images of the anterior eye segment from 23 young and 15 presbyopic em...AIM: To quantify the changes in the lens profile with accommodation in different age groups. METHODS: The Pentacam HR system was used to obtain the images of the anterior eye segment from 23 young and 15 presbyopic emmetropic subjects in unaccommodated (with an accommodation stimulus of 0.0D) and accommodated (with an accommodation stimulus of 5.0D for the young group and 1.0D for the presbyopic group) states. The phakic crystalline lens shape, including curvature of crystalline lens and central lens thickness (CLT), and the measurements of anterior segment length (ASL), central anterior chamber depth (CACD) were investigated. The anterior chamber volume (ACV) was also measured. RESULTS: The reduction of CACD and ACV were significant in both groups after accommodation stimulus. From the profile of anterior eye segment, a significant decrease in anterior crystalline lens radii of curvature (-2.52mm) and a mean increase in CLT (0.222mm) and ASL (0.1138mm) were found in the. young group with an accommodation stimulus of 5.0D. However, no statistically significant changes of CLT, ASL, or crystalline lens radii of curvature were found in the presbyopic group. CONCLUSION: Our data showed that the shallowing of anterior chamber during accommodation was caused by the forward bulging of the anterior lens surface, rather than by anterior shifting of lens position in either young or presbyopic subjects.展开更多
AIM： To analyze and compare five different variables over one year follow-up（1 wk, 1, 3, 6 and 12 mo）： anterior capsule（AC）, and posterior capsule（PC） area densitometry values, AC and PC linear densitometry va...AIM： To analyze and compare five different variables over one year follow-up（1 wk, 1, 3, 6 and 12 mo）： anterior capsule（AC）, and posterior capsule（PC） area densitometry values, AC and PC linear densitometry values, and AC opening area reduction ratio after femtosecond laserassisted cataract surgery. METHODS： This was a prospective comparative study. Seventy-one patients underwent femtosecond laser-assisted cataract surgery on single eye between June 2014 and December 2015. A 5.0 mm diameter laser assisted anterior capsulotomy was performed on all eyes. In every postsurgery evaluation, AC opacificaction（ACO） and PC opacification（PCO） density levels were provided by Oculus Pentacam·HR using area and linear densitometry methods. Digital images were captured with a slit-lamp Topcon photographic camera and IMAGEnet· 5 software. The AC opening area on the digital images was measured using the Sketchandcalc area calculator and converted to reduction ratio levels.RESULTS： Using Pearson correlation coefficient（PCC）, we found no correlation（r=-0.091, P=0.46） in the twelfth month assessment between the evolution of ACO area densitometry values and PCO area densitometry values considered as independent variables. We found no correlation, using PCC（r=-0.096, P=0.43） between the evolution of ACO linear densitometry values and PCO linear densitometry values, in the twelfth month visit, working both as independent variables. AC linear densitometry levels and AC area densitometry levels continued to grow strongly from sixth to twelfth months. Analysis of the values of AC opening area reduction ratio（1 wk, 1, 3, 6, 12 mo） revealed statistically significant differences between the values of successive examinations but the magnitude of the change decreased. In the final period of monitoring between six and twelve months the magnitude of change was low.CONCLUSION： Our results show strong increases of Scheimpflug ACO densitometry values from the sixth to the twelfth month while capsulorhexis area reduction ratio levels displayed a considerable decrease. We found no correlation between ACO area and linear densitometry values and PCO area and linear densitometry values, in the twelfth month examination, working as independent variables.展开更多
基金Supported by National Natural Science Foundation of China (No. 81070747)Research Award for New Century Excellent Talents in University (No. NCET08-0586)in ChinaScience and Technology Planning Project of Guangdong Province, China (No.2010B090400416)
文摘AIM: To quantify the changes in the lens profile with accommodation in different age groups. METHODS: The Pentacam HR system was used to obtain the images of the anterior eye segment from 23 young and 15 presbyopic emmetropic subjects in unaccommodated (with an accommodation stimulus of 0.0D) and accommodated (with an accommodation stimulus of 5.0D for the young group and 1.0D for the presbyopic group) states. The phakic crystalline lens shape, including curvature of crystalline lens and central lens thickness (CLT), and the measurements of anterior segment length (ASL), central anterior chamber depth (CACD) were investigated. The anterior chamber volume (ACV) was also measured. RESULTS: The reduction of CACD and ACV were significant in both groups after accommodation stimulus. From the profile of anterior eye segment, a significant decrease in anterior crystalline lens radii of curvature (-2.52mm) and a mean increase in CLT (0.222mm) and ASL (0.1138mm) were found in the. young group with an accommodation stimulus of 5.0D. However, no statistically significant changes of CLT, ASL, or crystalline lens radii of curvature were found in the presbyopic group. CONCLUSION: Our data showed that the shallowing of anterior chamber during accommodation was caused by the forward bulging of the anterior lens surface, rather than by anterior shifting of lens position in either young or presbyopic subjects.
文摘AIM： To analyze and compare five different variables over one year follow-up（1 wk, 1, 3, 6 and 12 mo）： anterior capsule（AC）, and posterior capsule（PC） area densitometry values, AC and PC linear densitometry values, and AC opening area reduction ratio after femtosecond laserassisted cataract surgery. METHODS： This was a prospective comparative study. Seventy-one patients underwent femtosecond laser-assisted cataract surgery on single eye between June 2014 and December 2015. A 5.0 mm diameter laser assisted anterior capsulotomy was performed on all eyes. In every postsurgery evaluation, AC opacificaction（ACO） and PC opacification（PCO） density levels were provided by Oculus Pentacam·HR using area and linear densitometry methods. Digital images were captured with a slit-lamp Topcon photographic camera and IMAGEnet· 5 software. The AC opening area on the digital images was measured using the Sketchandcalc area calculator and converted to reduction ratio levels.RESULTS： Using Pearson correlation coefficient（PCC）, we found no correlation（r=-0.091, P=0.46） in the twelfth month assessment between the evolution of ACO area densitometry values and PCO area densitometry values considered as independent variables. We found no correlation, using PCC（r=-0.096, P=0.43） between the evolution of ACO linear densitometry values and PCO linear densitometry values, in the twelfth month visit, working both as independent variables. AC linear densitometry levels and AC area densitometry levels continued to grow strongly from sixth to twelfth months. Analysis of the values of AC opening area reduction ratio（1 wk, 1, 3, 6, 12 mo） revealed statistically significant differences between the values of successive examinations but the magnitude of the change decreased. In the final period of monitoring between six and twelve months the magnitude of change was low.CONCLUSION： Our results show strong increases of Scheimpflug ACO densitometry values from the sixth to the twelfth month while capsulorhexis area reduction ratio levels displayed a considerable decrease. We found no correlation between ACO area and linear densitometry values and PCO area and linear densitometry values, in the twelfth month examination, working as independent variables.
