阈值改良 Amsler 表与 Humphrey 静态视野分析仪对青光眼视野检查的比较

对５０只正常眼和４７只青光眼进行阈值改良Ａｍｓｌｅｒ表与Ｈｕｍｐｈｒｅｙ静态分析仪视野检查比较，两种方法存在着相关关系，阳性检出率无区别，提示阈值改良Ａｍｓｌｅｒ表对青光眼早期视野损害有较高的检出率。     

Perimetric variability: Importance of criterion level

Perimetry suffers from considerable variability of results. A new technique for estimating individual criterion levels in normal subjects exposes the important role of psychological variables. The analysis depends on features peculiar to acuity perimetry. It can be accommodated in the regular examination. The results can be used to compensate for practice effects in serial examinations and to tighten the range of normal limits. The reduction in variation between normal subjects amounted to 57 per cent.     

青光眼患者相对性瞳孔反射传入障碍与其两眼视野面积差值的比较

对伴有相对性瞳孔反射传入障碍（RAPD）的26例非对称性青光眼（17例原发性开角型青光眼和9例青睫综合征）患者，将RAPD定量值与其两眼视野面积差值（VFAD）进行相关分析。结果显示Ⅰ2e、Ⅰ4e和Ⅲ4e等视线VFAD与RAPD值的相关系数分别为0.70、0.81和0.88，各相关系数经统计学检验均有极显著意义（P＜0.001）。表明RAPD测量在揭示青光眼不对称性视功能损害方面与视野检查具有一致性。因而RAPD可以作为非对称性青光眼视功能损害的重要体征之一。     

Visual field in hysteria-reliability of visual field by Goldmann perimetry

Four cases with hysterical amblyopia in youngsters under 15-year-old showed the poor reproducibility of visual field, that is, when the same target was moved from the periphery toward the fixation ten times along the same meridian during the same examination, the position of the plotted points were rather variable. The range of variation was measured from the innermost point to the outermost one, after the two first points were omitted because points first detected were usually far from the others. The variation of cases measured by this method was compared with that of normal persons. Results were as follows; 1. in normal person, the mean value of its range was 5.5° in first decade and 4.2° in second to seventh decade; 2. patients with psychogenic visual disturbances showed a variability of 14.2°, and this was significantly different from normal (p < 0.01). These results suggest that this convenient method was helpful for diagnosis of hysteria. It should also be remembered that when we evaluate the visual field, changes under 4° are probably not significant.     

Extrapolating global visual field indices from local parameters in the nasal region

The local mean and the average difference of four pairs of test locations within the 26° visual field, situated above and below the horizontal nasal meridian, were used to predict the global field indices MD and CLV of the Gl glaucoma program. Out of 539 examinations (194 eyes suspected of having glaucoma), the local indices NDIFF (describing asymmetrical behavior around the nasal horizontal meridian), ND0 (the mean defect in the nasal region), and the global indices MD and CLV were calculated. Seven hundred fifty-five examinations (446 normal eyes) served as a control group. First and second examinations of 146 glaucoma suspect eyes were used to calculate the retest reliability scores for the indices in question. When analyzing the glaucoma suspects, the local index NDIFF, together with the local mean defect, ND0, yielded highly reliable estimates of the global indices MD and CLV, with a retest correlation r = 0.86 for NDIFF, and r = 0.96 for ND0. The covariance of NDIFF with CLV was r = 0.67, while the co-variance of MD with ND0 was r = 0.95.The ranges of the local indices ND0 and NDIFF were each classified into normal range and range of suspected pathology, in analogy to the normal and pathological ranges of the global field indices. Equivalence of the local indices with the corresponding ranges of MD and CLV was investigated and the results are shown. The establishment of local indices may prove to be a powerful tool in early detection of glaucomatous damage.     

Suppression scotomas in primary microstrabismus — a perimetric artefact

Static perimetry with stereoscopic targets, stereo-perimetry, was performed on eight patients with primary microstrabismus to find out how strabismic subjects see under natural conditions, i.e. how they ordinarily make use of their squinting eye. In all cases, suppression scotomas were detectable using dissociating perimetric techniques. By means of stereoperimetry, however, the scotomas were not detectable. On the contrary, stereo-acuity was always best in the center of the suppression scotomas. This result indicates that suppression scotomas of the microstrabismic subjects examined here represented perimetric artefacts. In microstrabismic pateints, the cooperation of the deviated eye in the central visual field is probably much better than has previously been thought.     

Visual field deficits in cats reared with cyclodeviations of the eyes

Summary Visual fields of ten cats which had one or both eyes rotated at 8 days of age were measured by two forms of perimetry and compared to visual fields of two normal cats and of four cats with monocular rotations at 16 days, 3 months or 6 months of age. All animals showed excellent localization of visual stimuli and responded to the actual location of stimuli in space rather than to the retinal locus normally associated with that location. In cats with monocular rotations, the field of the normal eye was always normal, extending from 90 ° ipsilateral to 30 ° contralateral. Cats with rotations of one eye at 3 or 6 months of age had essentially normal fields in the rotated eye as well, while cats with surgery at 8 or 16 days had restricted horizontal fields. They responded only to stimuli in the ipsilateral hemifield; they were blind in the contralateral hemifield. Their superior and inferior visual fields were normal. The field deficits related consistently to visual field coordinates and not to the angle or direction of rotation. In cats with binocular rotations the visual field of at least one eye extended across the midline. Thus, the extent of the field depended upon sensorimotor experiences of the cat both before and after surgery. It is argued that these monocular field deficits have a central origin, not a retinal one.When tested with both eyes open, seven of 14 experimental animals did not respond throughout the visual field seen by each eye alone. The total visual field with both eyes open was less than the sum of the two monocular fields; greatest losses were most pronounced in the extreme periphery of the field ipsilateral to the rotated eye. Since changes in eye position (e.g., convergence during bincocular viewing) were not observed, it is suggested that the binocular losses indicate suppression of the deviated eye which has a central origin.All animals were tested for visual following, visually-triggered extension (placing), and visually-guided reaching. Cats which had been routinely encouraged to use the rotated eye(s) by occlusion of the other eye showed skilful performance within a few weeks after surgery as previously reported by Peck and Crewther (1975), Mitchell et al. (1976) and others. In contrast, two cats reared with both eyes open after unilateral rotation in infancy were profoundly handicapped, as previously reported by Yinon (1975, 1976).This research was supported by Grant NS 14116 from the US Public Health Service     

Conversion factor for comparison of data from Humphrey and Medmont automated perimeters

Background : Clinical experience has shown that the sensitivity indices reported by the Humphrey Field Analyser (HFA) are generally higher than those given by the Medmont Automated Perimeter (M600). It is the purpose of this paper to determine a conversion factor for the two perimeters and to confirm this prediction using clinical data. Theory predicted that HFA_sensitivity ? 5 dB = M600_sensitivity. Methods : Sensitivity versus eccentricity profiles were measured over the central visual field on 10 young subjects using both perimeters. Results : Both the HFA and the M600 operate within the realms of the Weber law and measure similar Weber fractions. The sensitivity profiles had similar slopes (about ?0.2 dB/degree) and were separated by about six decibels with the HFA reporting higher sensitivity values. This result confirmed the theoretical prediction. Conclusion : The difference in threshold sensitivities between the two perimeters is a result of differences in scaling factors and instrument luminances. A suggested clinical conversion factor is to subtract 5 dB from the HFA data to approximate those of the M600.     

老年性黄斑变性的黄斑部光敏感度检测

目的　探讨老年性黄斑变性早期患者黄斑暗视敏感度的变化。方法　用Octopus10 1型视野计 ,对早期老年性黄斑变性组 2 0例 30眼 ,对照组正常人 2 1例 2 6眼进行暗视和明视敏感度检测 ,应用tM2 测试程序 ,将中心 30°视野内视网膜暗视和明视敏感度进行比较和分析。结果　老年性黄斑变性组暗视和明视敏感度较正常组均降低 ,且暗视敏感度降低值大于明视敏感度降低值 ,差异显著 (P <0 .0 5 )。结论黄斑暗视敏感度检测可作为老年性黄斑变性早期诊断和检测指标。