AIM： To determine age norms in the first three years of life for grating visual acuity and contrast sensitivity obtained with Lea grating test and Hiding Heidi low contrast face test. METHODS： Lea grating test was u...AIM： To determine age norms in the first three years of life for grating visual acuity and contrast sensitivity obtained with Lea grating test and Hiding Heidi low contrast face test. METHODS： Lea grating test was used to estimate binocular grating acuity and Hiding Heidi low contrast face test was used to estimate contrast sensitivity in 600 healthy infants and children. Age ranged from 3 to 36 mo subdivided into 12 groups subjected for full ophthalmologic and pediatric examinations.RESULTS： The grating acuity developed along the first three years of life. It ranged from 1.88±0.32 c/d at 3mo to 30.95±0.77 c/d at 36 mo. The most rapid development was during the first 12 mo and the slowest development was from 30 to 36 mo. The contrast sensitivity showed rapid development in the first two years of life. Its mean value ranged from 4.23±1.17 at 3mo to 78.26±8.21 at 24 mo. It was constant at the highest score（80） thereafter.CONCLUSION： Age norms for grating acuity along with contrast sensitivity offer a more comprehensive measure of spatial vision and should be incorporated in clinical practice for better visual assessment in preverbal and nonverbal children.展开更多
目的:基于上腔静脉与主动脉弓达峰时间差构建对比剂剂量计算模型,消除锁骨下静脉及上腔静脉对比剂滞留伪影对颈动脉CT血管造影(CTA)的干扰。方法:前瞻性选取2024年3月—2025年3月中国人民解放军联勤保障部队第九七〇医院76例行颈动脉CT...目的:基于上腔静脉与主动脉弓达峰时间差构建对比剂剂量计算模型,消除锁骨下静脉及上腔静脉对比剂滞留伪影对颈动脉CT血管造影(CTA)的干扰。方法:前瞻性选取2024年3月—2025年3月中国人民解放军联勤保障部队第九七〇医院76例行颈动脉CTA检查的患者,按照随机数字表法分为对照组(n=39)与观察组(n=37)。对照组采用对比剂70 mL+0.9%氯化钠注射液40 mL固定剂量方案;观察组通过小剂量测试法测定上腔静脉达峰时间(T1)与主动脉弓达峰时间(T2),依据时间差动态计算对比剂总剂量,并追加40 mL 0.9%氯化钠注射液冲洗。评估两组图像质量优良率,比较锁骨下静脉、上腔静脉、同层颈静脉、胸主动脉弓、右侧颈总动脉CT值。结果:观察组图像质量优良率(94.59%)高于对照组(74.36%)(P<0.05)。观察组锁骨下静脉、上腔静脉、同层颈静脉血管CT值低于对照组(P<0.05),两组胸主动脉弓、右侧颈总动脉血管CT值比较差异无统计学意义(P>0.05)。结论:基于上腔静脉与主动脉弓达峰时间差构建对比剂剂量计算模型,可有效抑制静脉系统对比剂滞留伪影,提高颈动脉CTA图像质量,具有重要临床应用价值。展开更多
Recent studies indicated that except for the land-sea thermal contrast,there also existed the land-land thermal contrast.The composite analysis and t-test method are used to further study the local thermal contrast va...Recent studies indicated that except for the land-sea thermal contrast,there also existed the land-land thermal contrast.The composite analysis and t-test method are used to further study the local thermal contrast variation over the Asian continent,and to discuss the association of seasonal variation of land thermal state with circulation over East Asia,the early summer and summer monsoon activity,and the precipitation anomaly in China in the decadal scale.Results show that the positive meridional temperature anomaly transports downward from upper tropospheric layers in middle-high latitudes north of 25°N in the positive years.In the zonal direction,the Tibetan Plateau heating in the successive spring acts as a force to influence the atmosphere,leading to the rapid temperature warming over eastern Chinese continent,which could increase the land-sea thermal contrast with the negative SSTA.Accordingly,the monsoon activity in early summer over East Asian establishes earlier and the summer monsoon intensity becomes stronger.The early summer precipitation is more-than-normal over the Yangtze River,and the summer precipitation is more-than-normal over the north China and the southwest China.The situation is contrary in the negative years.展开更多
文摘AIM： To determine age norms in the first three years of life for grating visual acuity and contrast sensitivity obtained with Lea grating test and Hiding Heidi low contrast face test. METHODS： Lea grating test was used to estimate binocular grating acuity and Hiding Heidi low contrast face test was used to estimate contrast sensitivity in 600 healthy infants and children. Age ranged from 3 to 36 mo subdivided into 12 groups subjected for full ophthalmologic and pediatric examinations.RESULTS： The grating acuity developed along the first three years of life. It ranged from 1.88±0.32 c/d at 3mo to 30.95±0.77 c/d at 36 mo. The most rapid development was during the first 12 mo and the slowest development was from 30 to 36 mo. The contrast sensitivity showed rapid development in the first two years of life. Its mean value ranged from 4.23±1.17 at 3mo to 78.26±8.21 at 24 mo. It was constant at the highest score（80） thereafter.CONCLUSION： Age norms for grating acuity along with contrast sensitivity offer a more comprehensive measure of spatial vision and should be incorporated in clinical practice for better visual assessment in preverbal and nonverbal children.
文摘目的:基于上腔静脉与主动脉弓达峰时间差构建对比剂剂量计算模型,消除锁骨下静脉及上腔静脉对比剂滞留伪影对颈动脉CT血管造影(CTA)的干扰。方法:前瞻性选取2024年3月—2025年3月中国人民解放军联勤保障部队第九七〇医院76例行颈动脉CTA检查的患者,按照随机数字表法分为对照组(n=39)与观察组(n=37)。对照组采用对比剂70 mL+0.9%氯化钠注射液40 mL固定剂量方案;观察组通过小剂量测试法测定上腔静脉达峰时间(T1)与主动脉弓达峰时间(T2),依据时间差动态计算对比剂总剂量,并追加40 mL 0.9%氯化钠注射液冲洗。评估两组图像质量优良率,比较锁骨下静脉、上腔静脉、同层颈静脉、胸主动脉弓、右侧颈总动脉CT值。结果:观察组图像质量优良率(94.59%)高于对照组(74.36%)(P<0.05)。观察组锁骨下静脉、上腔静脉、同层颈静脉血管CT值低于对照组(P<0.05),两组胸主动脉弓、右侧颈总动脉血管CT值比较差异无统计学意义(P>0.05)。结论:基于上腔静脉与主动脉弓达峰时间差构建对比剂剂量计算模型,可有效抑制静脉系统对比剂滞留伪影,提高颈动脉CTA图像质量,具有重要临床应用价值。
基金Natural Science Fund projects of China(40675045,41065004)NSFC-Yunnan Joint Foundation(U0833602)National Public Benefit Research Foundation of China(GYHY201206017)
文摘Recent studies indicated that except for the land-sea thermal contrast,there also existed the land-land thermal contrast.The composite analysis and t-test method are used to further study the local thermal contrast variation over the Asian continent,and to discuss the association of seasonal variation of land thermal state with circulation over East Asia,the early summer and summer monsoon activity,and the precipitation anomaly in China in the decadal scale.Results show that the positive meridional temperature anomaly transports downward from upper tropospheric layers in middle-high latitudes north of 25°N in the positive years.In the zonal direction,the Tibetan Plateau heating in the successive spring acts as a force to influence the atmosphere,leading to the rapid temperature warming over eastern Chinese continent,which could increase the land-sea thermal contrast with the negative SSTA.Accordingly,the monsoon activity in early summer over East Asian establishes earlier and the summer monsoon intensity becomes stronger.The early summer precipitation is more-than-normal over the Yangtze River,and the summer precipitation is more-than-normal over the north China and the southwest China.The situation is contrary in the negative years.
