识别原发性青光眼视野缺损进展

视野检查是青光眼疾病进展的重要检测手段.即使是正常人,每一次视野检测也不可能完全重复上一次检测结果,都会出现短期波动和长期波动.这种光敏感度的生理波动会在青光眼患者的视野结果中明显增加,并混淆检测者发现真正的视野改变.因此,从这种生理波动中甄别出真正的青光眼视野缺损或进展,成了一项复杂的任务.用来判断青光眼视野进展的方法大概概括为四类:(1)临床评估系统最老的识别视野进展的方法,由多个观察员完全主观评估视野缺损情况,实行双盲评估视野缺损;(2)线性趋势外推法预测青光眼视野缺损本方法是基于最初5次视野检查结果,使用线性外推法预测将来患者的视野缺损;(3)逐点线性回归分析一种是在视野的不同点进行线性回归分析,另一种是基于视野列表指标的线性回归分析,通过Humphrey FieldAnalyzer(HFA)软件统计视野区的视野列表指标,视野中心区给予更多的加权;(4)新的青光眼进展指数为了更好的解释视野结果,对检测结果进行了年龄校正.这些方法都有自己的优势和不足,而且每一种方法都有使用的特殊条件;同时,也没有一种方法是完美的.目前最理想的判断青光眼视野缺损进展的方法,应该是根据一系列检查结果的明确改变,以及视野改变与其它临床观察值的相互关系进行判断.更新的帮助识别视野缺损进展的方法在不久的将来就会出现.

Identification of Progressive Glaucomatous Visual Field Loss

In normal individuals,visual field measures are not perfectly repeatable and individual test locations exhibit both short and long-term sensitivity variations.This physiologic variability is greatly increased in glaucoma and confounds detection of real progressive loss in visual function.Distinguishing progressive glaucomatous visual field loss from test variability therefore represents a complex task.Procedures used for detection of glaucomatous visual field progression may be broadly grouped into four categories:(1)clinical judgment,which consists of simple subjective observation of sequential visual field test results;(2)linear regression analysis: Linear extrapolation based on 5 initial visual field test results was a reliable predictor of future field loss in most patients;(3)pointwise linear regression analysis This new technique,which uses all available data in a field series and gives the rate of sensitivity loss at each location,may provide a clinically useful method for detecting field progression in glaucoma.and;(4)the glaucoma progression Index(GPI)Glaucoma progression rates calculated using the GPI seen to be congsiderably less affected by cataract and cataract surgery than rates base on the traditional,All of these methods demonstrate distinct benefits and drawbacks,making each useful in specific circumstances,although no single method appears universally ideal.At the present time the best method of detection of progression may be to rely upon confirmation of change at successive[Abstract]In normal individuals,visual field measures are not perfectly repeatable and individual test locations exhibit both short and long-term sensitivity variations.This physiologic variability is greatly increased in glaucoma and confounds detection of real progressive loss in visual function.Distinguishing progressive glaucomatous visual field loss from test variability therefore represents a complex task.Procedures used for detection of glaucomatous visual field progression may be broadly grouped into four categories:(1)clinical judgment,which consists of simple subjective observation of sequential visual field test results;(2)linear regression analysis: Linear extrapolation based on 5 initial visual field test results was a reliable predictor of future field loss in most patients;(3)pointwise linear regression analysis This new technique,which uses all available data in a field series and gives the rate of sensitivity loss at each location,may provide a clinically useful method for detecting field progression in glaucoma.and;(4)the glaucoma progression Index(GPI)Glaucoma progression rates calculated using the GPI seen to be congsiderably less affected by cataract and cataract surgery than rates base on the traditional,All of these methods demonstrate distinct benefits and drawbacks,making each useful in specific circumstances,although no single method appears universally ideal.At the present time the best method of detection of progression may be to rely upon confirmation of change at successive examinations and also by correlation of visual field changes with other clinical observations.Alternative analysis methods may become available in the near future to help identify cases of progressive loss.