AIM：To evaluate and compare structural optical coherence tomography（OCT）-based parameters,such as Bruch’s membrane opening-minimum rim width（BMO-MRW）,and retinal nerve fiber layer（RNFL）thickness in glaucoma pa...AIM：To evaluate and compare structural optical coherence tomography（OCT）-based parameters,such as Bruch’s membrane opening-minimum rim width（BMO-MRW）,and retinal nerve fiber layer（RNFL）thickness in glaucoma patients with visual field（VF）defects,and to correlate both to mean deviation（MD）values of obtained standard achromatic perimetry（SAP）examinations.METHODS：Patients with glaucoma and glaucomatous VF defects were enrolled in this prospective study and compared to age-matched healthy individuals.All study participants underwent a full ophthalmic examination and VF testing with SAP.Peripapillary RNFL thickness and BMO-MRW were acquired with SD-OCT.Correlation analyses between obtained global functional and global as well as sectorial structural parameters were calculated.RESULTS：A consecutive series of 30 glaucomatous right eyes of 30 patients were included and compared to 36healthy right eyes of 36 individuals in the control group.Global MD of values correlated significantly with global RNFL（Pearson corr.coeff：0.632,P=0.001）and global BMO-MRW（Pearson corr.coeff：0.746,P〈0.001）values in the glaucoma group.Global MD and sectorial RNFL or BMO-MRW values correlated less significantly.In the control group,MD values did not correlate with RNFL or BMO-MRW measurements.A subgroup analysis of myopic patients（〉4 diopters）within the glaucoma group（n=6）revealed a tendency for higher correlations between MD and BMO-MRW than MD and RNFL measurements.CONCLUSION：In a clinical setting,RNFL thickness and BMO-MRW correlate similarly with global VF sensitivity in glaucoma patients with BMO-MRW showing higher correlations in myopic glaucoma patients.展开更多
AIM：To determine the Bruch＇s membrane opening-minimum rim width（BMO-MRW） tipping point where corresponding visual field（VF） damages become detectable.METHODS：A total of 85 normal subjects and 83 glaucoma patie...AIM：To determine the Bruch＇s membrane opening-minimum rim width（BMO-MRW） tipping point where corresponding visual field（VF） damages become detectable.METHODS：A total of 85 normal subjects and 83 glaucoma patients（one eye per participant） were recruited for the study.All of the patients had VF examinations and spectral-domain optical coherence tomography to measure the BMO-MRW.Total deviation values for 52 VF points were allocated to the corresponding sector according to the Garway-Heath distribution map.To evaluate the relationship between VF loss and BMOMRW measurements,a ＂broken-stick＂ statistical model was used.The tipping point where the VF values started to sharply decrease as a function of BMO-MRW measurements was estimated and the slopes above and below this tipping point were compared.RESULTS：A 25.9% global BMO-MRW loss from normative value was required for the VF loss to be detectable.Sectorally,substantial BMO-MRW thinning in inferotemporal sector（33.1%） and relatively less BMO-MRW thinning in the superotemporal sector（8.9%） were necessary for the detection of the VF loss.Beyond the tipping point,the slopes were close to zero throughout all of the sectors and the VF loss was unrelated to the BMO-MRW loss.The VF loss was related to the BMO-MRW loss below the tipping point.The difference between the two slopes was statistically significant（P≤0.002）.CONCLUSION：Substantial BMO-MRW loss appears to be necessary for VF loss to be detectable in patients with open angle glaucoma with standard achromatic perimetry.展开更多
Floods are essential for the regeneration and growth of floodplain forests in arid and semiarid regions. However, river flows, and especially flood flows, have decreased greatly with the increase of water diversion fr...Floods are essential for the regeneration and growth of floodplain forests in arid and semiarid regions. However, river flows, and especially flood flows, have decreased greatly with the increase of water diversion from rivers and/or reservoir regulation, resulting in severe deterioration of floodplain ecosystems. Estimation of the flood stage that will inundate the floodplain forest is necessary for the forest＇s restoration or protection. To balance water use for economic purposes and floodplain forest protection, the inundated forest width method is proposed for estimating the minimum flood stage for floodplain forests from the inundated forest width-stage curve. The minimum flood stage is defined as the breakpoint of the inundated forest width-stage curve, and is determined directly or analytically from the curve. For the analytical approach, the problem under consideration is described by a multi-objective optimization model, which can be solved by the ideal point method. Then, the flood flow at the minimum flood stage （minimum flood flow）, which is useful for flow regulation, can be calculated from the stage-discharge curve. In order to protect the forest in a river floodplain in a semiarid area in Xinjiang subject to reservoir regulation upstream, the proposed method was used to determine the minimum flood stage and flow for the forest. Field survey of hydrology, topography, and forest distribution was carried out at typical cross sections in the floodplain. Based on the survey results, minimum flood flows for six typical cross sections were estimated to be between 306 m3/s and 393 m3/s. Their maximum, 393 m3/s, was considered the minimum flood flow for the study river reach. This provides an appropriate flood flow for the protection of floodplain forest and can be used in the regulation of the upstream reservoir.展开更多
文摘AIM：To evaluate and compare structural optical coherence tomography（OCT）-based parameters,such as Bruch’s membrane opening-minimum rim width（BMO-MRW）,and retinal nerve fiber layer（RNFL）thickness in glaucoma patients with visual field（VF）defects,and to correlate both to mean deviation（MD）values of obtained standard achromatic perimetry（SAP）examinations.METHODS：Patients with glaucoma and glaucomatous VF defects were enrolled in this prospective study and compared to age-matched healthy individuals.All study participants underwent a full ophthalmic examination and VF testing with SAP.Peripapillary RNFL thickness and BMO-MRW were acquired with SD-OCT.Correlation analyses between obtained global functional and global as well as sectorial structural parameters were calculated.RESULTS：A consecutive series of 30 glaucomatous right eyes of 30 patients were included and compared to 36healthy right eyes of 36 individuals in the control group.Global MD of values correlated significantly with global RNFL（Pearson corr.coeff：0.632,P=0.001）and global BMO-MRW（Pearson corr.coeff：0.746,P〈0.001）values in the glaucoma group.Global MD and sectorial RNFL or BMO-MRW values correlated less significantly.In the control group,MD values did not correlate with RNFL or BMO-MRW measurements.A subgroup analysis of myopic patients（〉4 diopters）within the glaucoma group（n=6）revealed a tendency for higher correlations between MD and BMO-MRW than MD and RNFL measurements.CONCLUSION：In a clinical setting,RNFL thickness and BMO-MRW correlate similarly with global VF sensitivity in glaucoma patients with BMO-MRW showing higher correlations in myopic glaucoma patients.
文摘AIM：To determine the Bruch＇s membrane opening-minimum rim width（BMO-MRW） tipping point where corresponding visual field（VF） damages become detectable.METHODS：A total of 85 normal subjects and 83 glaucoma patients（one eye per participant） were recruited for the study.All of the patients had VF examinations and spectral-domain optical coherence tomography to measure the BMO-MRW.Total deviation values for 52 VF points were allocated to the corresponding sector according to the Garway-Heath distribution map.To evaluate the relationship between VF loss and BMOMRW measurements,a ＂broken-stick＂ statistical model was used.The tipping point where the VF values started to sharply decrease as a function of BMO-MRW measurements was estimated and the slopes above and below this tipping point were compared.RESULTS：A 25.9% global BMO-MRW loss from normative value was required for the VF loss to be detectable.Sectorally,substantial BMO-MRW thinning in inferotemporal sector（33.1%） and relatively less BMO-MRW thinning in the superotemporal sector（8.9%） were necessary for the detection of the VF loss.Beyond the tipping point,the slopes were close to zero throughout all of the sectors and the VF loss was unrelated to the BMO-MRW loss.The VF loss was related to the BMO-MRW loss below the tipping point.The difference between the two slopes was statistically significant（P≤0.002）.CONCLUSION：Substantial BMO-MRW loss appears to be necessary for VF loss to be detectable in patients with open angle glaucoma with standard achromatic perimetry.
基金supported by the National Natural Science Foundation of China (Grant No.50879041)the New Century Excellent Talents in University (NCET) Program of the Ministry of Education of China (Grants No. 06-0059 and 07-0814)
文摘Floods are essential for the regeneration and growth of floodplain forests in arid and semiarid regions. However, river flows, and especially flood flows, have decreased greatly with the increase of water diversion from rivers and/or reservoir regulation, resulting in severe deterioration of floodplain ecosystems. Estimation of the flood stage that will inundate the floodplain forest is necessary for the forest＇s restoration or protection. To balance water use for economic purposes and floodplain forest protection, the inundated forest width method is proposed for estimating the minimum flood stage for floodplain forests from the inundated forest width-stage curve. The minimum flood stage is defined as the breakpoint of the inundated forest width-stage curve, and is determined directly or analytically from the curve. For the analytical approach, the problem under consideration is described by a multi-objective optimization model, which can be solved by the ideal point method. Then, the flood flow at the minimum flood stage （minimum flood flow）, which is useful for flow regulation, can be calculated from the stage-discharge curve. In order to protect the forest in a river floodplain in a semiarid area in Xinjiang subject to reservoir regulation upstream, the proposed method was used to determine the minimum flood stage and flow for the forest. Field survey of hydrology, topography, and forest distribution was carried out at typical cross sections in the floodplain. Based on the survey results, minimum flood flows for six typical cross sections were estimated to be between 306 m3/s and 393 m3/s. Their maximum, 393 m3/s, was considered the minimum flood flow for the study river reach. This provides an appropriate flood flow for the protection of floodplain forest and can be used in the regulation of the upstream reservoir.
