首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Interpretation of numeric automated threshold visual field results is often difficult. A large amount of data is obtained for every single field tested. Various approaches to summarize this data have been suggested, most commonly the mean and standard deviation of departures from age-corrected normal threshold values. These visual field indices differ substantially from subjective field interpretation where spatial relationships are important. We have previously devised two methods for automated field interpretation which take spatial information into account--regional up-down comparisons and arcuate cluster analysis. We now studied the merits of using these new spatial methods and compared them to traditional visual field indices for discrimination between normal and glaucomatous field results. Central static 30 degree field results in 101 eyes of 101 normal subjects and 101 eyes of 101 patients with glaucoma were discriminated using logistic regression analysis. The best field classification was obtained with a spatial visual field model combining up-down differences and arcuate clusters. The advantages of the spatial model were confirmed in an independent material of 163 eyes of 163 normal subjects and 76 eyes of 76 patients with glaucoma where eyes with large field defects had been removed. In this material the spatial model gave 87% sensitivity and 83% specificity while the best non-spatial model gave 82% sensitivity and 80% specificity. Visual field interpretation in glaucoma may be significantly enhanced if detection is focused on circumscribed field loss rather than on averages of differential light sensitivities and similar indices which do not take spatial relationships into consideration.  相似文献   

2.
The central visual fields of 2165 normal and 106 glaucoma eyes were measured using a threshold related suprathreshold strategy. The effects of altering the cluster radius in normals and glaucoma eyes sheds light on the nature of defects in these two groups. It is estimated that approximately 13% of normals have clusters; the great majority of these individuals have one cluster of two defects. Most clusters in normals are formed artefactually due to angioscotoma and/or physiological variations in the blind spot position. Clusters due to other factors occur rarely. Clusters are found with equal frequencies in the superior and inferior fields in normal eyes, but with a greater frequency in the superior field in glaucoma eyes.The use of clusters in quantification is both sensitive and specific. Using results from this large sample and looking at other visual field properties, it is possible to devise weighted probability indices to score visual fields.  相似文献   

3.
目的 评价趋势导向视野检查法(tendency-oriented perimetry, TOP)在青光眼视功能检测中的应用价值。 方法 利用Octopus 101全自动视野计分别对20名正常人的20只正常眼、32例原发性开角型青光眼(primary open angle glaucoma, POAG)患者的32只患眼和14例可疑POAG患者的14只眼分别进行常规阈值视野检查(Normal/Normal程序)和TOP视野检查(TOP/Normal程序)。所有受检眼在2周内再次分别进行常规阈值视野检查和TOP视野检查。将两种视野检查的结果、视野检查指数、点对点阈值变异及视野缺损点数进行比较和分析。 结果 TOP视野检查正常人的阴性检出率为90%,POAG的阳性检出率为75%,其中检测中晚期POAG的阳性检出率达100%。2种视野检查的视野指数呈明显正相关,平均敏感度(mean sensitivity, MS)的相关系数为0.9335,平均缺损(mean defect, MD)的相关系数为0.9189,偏离缺失(loss variance, LV)的相关系数为0.9621。点对点阈值变异和视野缺损点数TOP视野检查结果略高于常规阈值视野检查结果,但二者间差异均无显著性的意义(P=0.2019,P=0.4448)。 结论 TOP视野检查指数与常规阈值视野检查指数呈明显正相关,其检测中晚期POAG的敏感性及可重复性高。 (中华眼底病杂志, 2002, 18: 169-272)  相似文献   

4.
BACKGROUND: To investigate the clinical usefulness of the Heidelberg Retina Tomograph II (HRT II) in glaucoma-screening. MATERIAL AND METHODS: HRT II measurements were performed on 53 glaucomatous, 33 normal and 24 glaucoma suspect eyes. HRT II classification ("glaucoma", "borderline" and "normal") was compared to the classification of clinical examination (biomicroscopic indirect papilla examination, applanation tonometry, threshold perimetry) as well as to the classifications determined with threshold perimetry or GDx nerve fibre analysis simulating a screening examination. RESULTS: HRT II measurements were successful in 82.7 % of the eyes investigated. The diagnostic sensitivity of the HRT II was 60 %. Specificity was 88.8 % and 100 % at different criteria for "disease". HRT II classification corresponded the biomicroscopic classification in 63.7 %. The accordance of the HRT II classification with the GDx and visual field classification was 65.4 % and 64.8 %, respectively. GDx classification corresponded with the clinical and visual field classification in 41 % and 44 %. Significant (p < 0.05) positive correlation was between HRT II parameters cup/disc area ratio, linear C/D ratio and visual field indices MD and PSD. The HRT II parameter: Retinal Nerve Fibre Layer Cross Sectional Area and visual field index MD correlated in a significant negative manner. CONCLUSIONS: Though patient examination was fast using the HRT II instrument, the technique with the present software cannot be considered suitable for glaucoma screening, since its sensitivity is low. The HRT II seems to be useful when added to other diagnostic techniques.  相似文献   

5.
Time changes of contrast thresholds during automatic perimetry   总被引:1,自引:0,他引:1  
Contrast thresholds were continuously recorded in six points of the visual field through a repetitive up-and-down staircase method using the automatic perimeter developed by Heijl & Krakau (1975b). The uninterrupted sessions lasted about 30 min. Nineteen patients with a verified diagnosis of glaucoma, or in whom glaucoma was suspected, and twelve healthy normal subjects were tested. With increasing test time, a decreased contrast sensitivity was found. In most subjects the mean threshold increment was small (less than 1.5 dB). The threshold increments were larger in the patient group than in the normal subjects--many test points showing increments of 6-10 dB during the test session. Such a large deterioration of sensitivity was most common in eyes with visual field defects. Test points which showed large threshold increments were often situated in the vicinity of documented visual field defects. In eyes with pathological visual fields, the short-term variation increased with increasing test time. An impairment of fixation with increasing test time was found in the patient group.  相似文献   

6.
PURPOSE: To evaluate the Heidelberg Retina Tomograph III (HRT III) glaucoma probability score in differentiating normal from pathologic eyes and to compare the glaucoma probability score with Moorfields regression analysis (MRA). DESIGN: Prospective cross-sectional study. METHODS: Fifty-nine normal, 40 hypertensive, and 83 glaucomatous eyes were examined with Swedish interactive threshold algorithm standard 24-2 visual fields and HRT III. Sensitivity and specificity were evaluated using global and sectorial glaucoma probability score and MRA compared with damage in visual fields. Areas under receiver operating characteristic (ROC) curves were evaluated. Agreement between MRA and glaucoma probability score was calculated using the kappa coefficient. Glaucoma probability score was considered to be displaced when a symbol was outside and the opposite symbol was inside the optic disk. RESULTS: MRA sensitivity and specificity were 39.8% and 93.2% (most specific criteria) and 68.7% and 83.1% (least specific criteria), respectively. Glaucoma probability score sensitivity and specificity were 71.1% and 69.5% (most specific criteria) and 85.5% and 54.2% (least specific criteria), respectively. Visual field parameters were related to the global (P = .001) and sectorial (P < .05) glaucoma probability score. A displaced glaucoma probability score was found in 35 eyes, but with unchanged glaucoma probability score sensitivity and specificity. Areas under the ROC curves of glaucoma probability score was 0.77. The kappa coefficient was 0.34. CONCLUSIONS: Glaucoma probability score analysis tends to be more sensitive but less specific than MRA. Glaucoma probability score did not differentiate normal and hypertensives eyes. When displaced, glaucoma probability score sensitivity and specificity were unchanged. MRA and glaucoma probability score agreement was low. Glaucoma probability score is advantageous over MRA in early-stage glaucoma.  相似文献   

7.
目的 探讨国产YDS-201自动视野计四点阈值程序在青光眼视野筛查诊断中的临床应用价值.方法 采用国产YDS-201自动视野计的中心52及四点阈值程序对77例(140只眼)青光眼患者在半暗室环境下检测中心30°视野.分别进行定性、定位、检测时间的对比分析.结果 定性诊断:两种程序检查结果视野缺损部位一致的119只眼(85%),不一致的21只眼(15%);定位诊断:四个象限均符合者为118只眼,约占84.3%,两个或三个象限符合者为22只眼,约占15.7%,未见四个象限均不符合者;检测耗时:中心52程序检查用时183~638s,平均(302.13±99.02)s,四点阈值程序检查用时23~101s,平均(44.11±18.00)s,P<0.001.结论 YDS-201视野计四点阈值程序在快速筛查青光眼视野缺损中具有较高敏感性和特异性,检查用时短,适合于青光眼的视野筛查,是一种在大量人群中快速筛查青光眼的良好方法.  相似文献   

8.
AIM: To determine if global and segmental changes in optic disc parameters of sequential Heidelberg retina tomograph (HRT) images develop in individual ocular hypertensive (OHT) patients without white on white visual field defects. METHODS: Patients and normal controls were recruited from a prospective ocular hypertension treatment trial. The subject groups consisted of 21 OHT patients who had converted to early glaucoma on the basis of visual field criteria (24-2 program on the Humphrey perimeter), 164 OHT subjects with normal visual fields, and 21 normal controls. Sequential HRT images 16-21 months apart were obtained for each subject and segmental optic disc parameters were measured to determine if any change had occurred. From the analysis of sequential HRT images of the 21 normal eyes we established normal limits of interimage variation. Individual discs in each group showing changes above the 95% limit of normal variability were then sought. RESULTS: Several segmental and global optic disc parameters were found to show significant change in the converter group before confirmed visual field change, confirming our previously published results. Individual optic disc analysis using the 95% limit of normal variability data demonstrated glaucomatous change in 13 out of 21 converter eyes. 47 of the 164 OHT eyes with normal visual fields showed change in global and segmental parameters in a "glaucomatous" direction above the level expected for normal variability. The parameters which changed most frequently in the OHT eyes were: global cup volume (6.7% of discs), inferonasal cup volume (11%), inferotemporal cup volume (8.5%), and superotemporal cup area (7.3%). CONCLUSIONS: We have identified change in a subset of ocular hypertensive patients which could predate the development of glaucomatous visual field loss. The HRT could be of value in the sequential follow up of those suspected of having glaucoma by identifying eyes at risk of developing glaucoma. However, further refinement of the technique is required to eliminate some of the inherent variability of the analysis method described, and to increase the ability to detect at risk individuals.  相似文献   

9.
The influence of stimulus size and normal database on the detection of visual field defects in automated static threshold perimetry (Humphrey Field Analyzer) was investigated in 82 eyes having a diagnosis of normal, glaucoma suspect, or early glaucoma. Using a mathematically derived 'normal' database, which assumes constantly decreasing threshold sensitivities with increasing eccentricity, the size I stimulus showed significantly greater sensitivity than the size III stimulus for detecting small, shallow scotomata in the central visual field. The use of Statpac, which contains an empirically derived, age-related normal database, increased the sensitivity significantly over that of the size III stimulus (with its mathematical model), and to a degree similar to that of the size I stimulus. The results obtained with the size I stimulus were reproducible and independent of the patient's age. This study suggests a potential role for the size I stimulus in evaluating eyes having or at risk of developing early glaucomatous field loss.  相似文献   

10.
PURPOSE: To compare the prevalence of visual field loss, the sensitivity distribution, and the size and depth of glaucomatous visual field defects using the standard full threshold (FT) and the Swedish interactive threshold algorithm (SITA) standard (SS) procedures in patients with early or suspected glaucoma. METHODS: Automated perimetry findings were retrospectively evaluated in 53 patients (105 eyes) with early or suspected glaucoma. RESULTS: The number of eyes judged to have glaucomatous visual field loss by SS (48 eyes) was significantly larger than what was found with FT (35 eyes), and 70 eyes were classified as pre-perimetric glaucoma. In these 70 eyes, there were many locations where the sensitivity was significantly higher with SS than with FT (intrasubject difference), and SS had less intersubject variability than FT at most locations. The cumulative decibel scores at the region of glaucomatous defects were larger with SS (206.2+/-103.3 dB) than with FT (162.1+/-87.5 dB) (p=0.02), which indicated that the depth of defects measured by SS was shallower than that by FT. The sizes of defects were significantly larger with SS (11.2+/-5.6) than with FT (9.7+/-5.1) (p<0.05). CONCLUSIONS: Glaucomatous defects were measured as being significantly shallower and larger with SS than with FT. In addition, the prevalence of visual field defect was higher with SS according to some of the criteria for glaucomatous visual field defects. These results might be related to the fact that SS strategy has a lower variability and to the Bayesian statistical properties of the SITA algorithm.  相似文献   

11.
探讨原发性开角型青光眼和低压性青光眼早期视野损害及视网膜神经纤维层缺损的特点。  相似文献   

12.
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。  相似文献   

13.
PURPOSE: To determine the sensitivity and specificity of two new visual field algorithms in detecting glaucomatous visual field defects: (1) Swedish interactive threshold algorithm (SITA) standard and (2) SITA fast. DESIGN: Prospective observational case series. PARTICIPANTS: Ninety normal subjects and 82 glaucoma patients. TESTING: Central 30 degrees fields were performed with the Humphrey visual field analyzer 30-2 program (Humphrey Systems, Dublin, CA) using full threshold, SITA standard, and SITA fast algorithms on the same day for two or more sessions within a 1-month period. MAIN OUTCOME MEASURES: Sensitivity and specificity in detecting glaucomatous visual field defects with SITA standard and SITA fast using full threshold testing as the reference standard. RESULTS: The sensitivity of SITA standard and SITA fast in detecting glaucomatous defects overall was 98% and 95%, respectively. In the subset of mild glaucomatous field defects (26 patients), sensitivity of SITA standard was 92% versus 85% with SITA fast. Sensitivity was 100% for both algorithms in moderate to severe glaucomatous defects. Specificity for glaucoma defects using SITA standard and SITA fast was 96% for both algorithms. SITA standard reduced test-taking time from full threshold by 52% in normal subjects and 47% in glaucoma patients (P < 0.001). SITA fast reduced test-taking time by 72% in normal subjects and 65% in glaucoma patients (P < 0.001). Mean deviation values were 0.4 dB and 0.8 dB better in SITA standard and SITA fast fields, respectively, in normal subjects (P < 0.001), and 0.7 dB and 1.2 dB in SITA standard and SITA fast fields, respectively, in glaucoma patients (P < 0.001) compared with full threshold values. CONCLUSIONS: The new algorithms for measuring visual fields, SITA standard and SITA fast, have excellent sensitivity and specificity for glaucomatous visual field loss with considerable savings in time.  相似文献   

14.
BACKGROUND: The "Swedish Interactive Threshold Algorithm" (SITA) is a new technique minimizing test time without reduction of data quality. In this retrospective study we compared visual fields assessed with the conventional full-threshold technique with those by SITA and analyzed qualitative and quantitative differences and the test time reduction of SITA. PATIENTS AND METHODS: 113 eyes with different glaucomatous field damage of 66 patients aged from 22 to 89 years were included. The patients underwent perimetry with each strategy within four months. Exclusion criteria were eyes with progressing glaucomatous damage and high rate of false-positive results or artifacts by corrective glasses. RESULTS: The qualitative differences of the analysis were small: full threshold demonstrated more relative scotomas in eyes with normal SITA readings, whereas scotomas assessed with SITA were often pronounced to absolute scotomas. Average time reduction by SITA was 40% and depended on the severity of glaucomatous stage. No reduction was found for advanced glaucoma, whereas normal fields using SITA were performed in half of the time of full threshold strategy. CONCLUSION: Differences of SITA to conventional full threshold testing may be related to fatigue effects of full threshold strategy due to longer test time. The reduction of test time enables more motivation for more frequent visual field examinations and thus a better detection of early glaucoma or progressing visual field damage.  相似文献   

15.
Test-retest variability in glaucomatous visual fields   总被引:6,自引:0,他引:6  
We measured test-retest variations in computerized visual fields from glaucomatous eyes. Fifty-one patients were tested four times within a four-week period; the severity of disease varied from incipient to advanced. We determined the dependence of threshold variability on defect depth and test point location. In areas of the visual field initially found to have moderate loss of sensitivity, variation in follow-up measurements ranged from normal sensitivity to absolute defect, with little dependence on distance from fixation. Conversely, large changes were considerably more unusual in locations initially showing normal or near-normal sensitivities, and variability was lowest in the most central portion of the field. Our findings suggest that differentiation between true progression and random variation will be facilitated if these factors are taken into account, as well as if comparisons are based on more than two tests. The complex nature of interest variation in glaucoma makes it natural to approach this problem with the help of computer-assisted analyses.  相似文献   

16.
Evaluation of VEP perimetry in normal subjects and glaucoma patients   总被引:3,自引:0,他引:3  
PURPOSE: To estimate sensitivity to glaucomatous visual field loss using multifocal visual evoked potential (VEP) perimetry, to compare these findings to those of conventional achromatic perimetry and to determine specificity of VEP perimetry in normal subjects. METHODS: A total of 33 glaucoma patients with known visual field defects in at least one eye on standard computerized perimetry and 33 healthy subjects were tested with VEP perimetry. The glaucoma patients were also tested with standard computerized perimetry using the 30-2 SITA Fast program of the Humphrey Field Analyzer (HFA). Visual evoked potential perimetry classification and VEP probability maps were used to determine the sensitivity and specificity of the technique. RESULTS: Visual evoked potential perimetry classified 68% of all eyes in the glaucoma group (45/66) as pathological; sensitivity increased to 81% (38/47) when considering only those eyes with HFA field defects. It also identified more test locations with significant loss at the p < 5% level in both groups (48% and 37%, respectively) than did HFA, while HFA identified more loss at the higher significance levels p < 2%, and p < 1%. Visual evoked potential perimetry showed more significant loss in eyes with almost normal or slightly damaged standard fields, while HFA identified more significant field loss in eyes with severe conventional field damage. The mean VEP amplitude of the 66 glaucoma eyes was 1.46e(-7) V; it was 1.676e(-7) V for the 66 control eyes. This difference was significant (p = 0.0033), but the overlap between groups was large. Visual evoked potential perimetry classified 42% of the control eyes as 'outside normal limits', and VEP probability maps showed 30.0% of test segments as significantly depressed at the p < 5% level, 10.8% of sites at p < 2%, and 4.6% at the p < 1% level. CONCLUSION: Mean VEP amplitude differed significantly between normal and glaucoma eyes, but the overlap was considerable. Visual evoked potential perimetry falsely classified a large number of normal eyes as pathological and showed many more significantly depressed test locations than expected. Agreement between VEP and standard perimetry was relatively poor for the glaucoma group. Further refinements are needed before VEP perimetry can be regarded as a reliable clinical method of mapping glaucomatous visual fields.  相似文献   

17.
· Background: Delphi perimetry is a method of visual field examination which produces a statistical estimation of the visual field by testing only four critical points of the central visual field. This study was performed to evaluate this technique for the detection of glaucomatous field loss. · Method: Patients with glaucoma and ocular hypertension underwent Delphi perimetry and Humphrey visual field analysis (HVFA) program 24-2. The visual field results of both examination were compared. · Results: Of 262 eyes from 199 patients, 120 eyes showed glaucomatous defects by HVFA and 142 were normal. Delphi perimetry showed abnormal visual fields in 107 eyes, 13 of which were false-positive results as Humphrey visual fields were normal. Delphi classified 155 fields as normal, of which 26 were false negatives as Humphrey visual fields showed glaucomatous defects. Therefore, the sensitivity of Delphi perimetry for the detection of glaucomatous visual field defect was 78% and the specificity was 91%. In the 26 false-negative eyes, the most common defect missed was an isolated paracentral scotoma or an early nasal step. Furthermore, 27 of the 94 glaucomatous eyes classified as abnormal by Delphi had defects estimated by Delphi perimetry that corresponded poorly to the field loss demonstrated by Humphrey visual field analysis. Therefore, qualitative sensitivity and specificity of Delphi perimetry for producing an accurate representation of the location, extent and defect depth of glaucomatous visual field loss would be 48.8% and 72% respectively. · Conclusion: In this study Delphi perimetry failed to give an accurate statistical estimation of the visual field in an unacceptably high number of cases; therefore, it cannot be recommended for clinical use. Received: 12 June 1997 Revised version received: 11 November 1997 Accepted: 13 November 1997  相似文献   

18.
AIM: To evaluate the ability of confocal scanning laser tomography of the optic nerve head to detect glaucomatous optic nerve damage in ocular hypertensive eyes without visual field defects. METHODS: The study included 50 normal subjects, 61 glaucoma patients with glaucomatous changes in the optic disc and visual field, and 102 "preperimetric" patients with increased intraocular pressure, normal visual fields, and glaucomatous appearance of the optic disc as evaluated on colour stereo optic disc photographs. For all individuals, confocal scanning laser tomographs of the optic nerve head were taken using the Heidelberg retina tomograph (HRT; software 2.01). RESULTS: Almost all investigated HRT variables varied significantly (p < 0.05) between the normal eyes and preperimetric glaucoma eyes with pronounced overlap between the two study groups. Corresponding to the overlap, sensitivity and specificity values were relatively low when HRT variables were taken to differentiate between normal and preperimetric glaucoma eyes. At a given specificity of 95% highest sensitivities were found for the variables "rim area in the superior disc sector" (24.8%), "nerve fibre layer thickness in the inferior disc sector" (26.5%), and "rim volume in the superior disc sector" (25.5%). A multivariate approach increased sensitivity to 42.2% at a given specificity of 95%. For the glaucoma group highest sensitivity values were reached by rim volume in the superior disc sector (73.8%) and rim area (72.1%); the multivariate approach reached 83.6%. CONCLUSIONS: Owing to pronounced overlapping between the groups, confocal scanning laser tomography of the optic nerve head has relatively low diagnostic power to differentiate between normal eyes and preperimetric glaucoma eyes. One of the reasons may be the biological interindividual variability of quantitative optic disc variables.  相似文献   

19.
PURPOSE: To determine whether a variational Bayesian independent component analysis mixture model (vB-ICA-mm), a form of unsupervised machine learning, can be used to identify and quantify areas of progression in standard automated perimetry fields. METHODS: In an earlier study, it was shown that a model using vB-ICA-mm can separate normal fields from fields with six different patterns of visual field loss related to glaucomatous optic neuropathy (GON) along maximally independent axes. In the present study, an independent group of 191 patient eyes (66 with ocular hypertension (OHT), 12 with suspected glaucoma by field, 61 with suspected glaucoma by disc, and 52 with glaucoma) with five or more standard visual fields under observation for a mean of 6.24 +/- 2.65 years and 8.11 +/- 2.42 visual fields were evaluated with the vB-ICA-mm. In addition, eyes with progressive GON (PGON) were identified (n = 39). Each participant had a series of fields tested, with each field entered independently and placed along the axes of the previously developed model. This allowed change in one pattern of visual field defect (along one axis) to be assessed relative to results other areas of that same field (no change along other axes). Progression was based on a slope falling outside the 5th and the 95th percentile limits of all slopes, with at least two axes not showing such a deviation in a given individual's series of fields. Fields were also scored using Advanced Glaucoma Intervention Study (AGIS) and the Early Manifest Glaucoma Treatment Trial (EMGT) criteria. RESULTS: Thirty-two of 191 eyes progressed on vB-ICA-mm by this definition. Of the 32, 22 had field loss at baseline, 7 had only GON, 3 were OHTs and 12 were from the 39 eyes (31%) with PGON. The vB-ICA-mm identified a higher percentage of progressing eyes in each diagnostic category than did AGIS or and the EMGT. CONCLUSIONS: The vB-ICA-mm can quantitatively identify progression in eyes with glaucoma by evaluating change in one or more patterns of the visual field loss while other areas or patterns remain stable. This may enable each eye to contribute to the determination of whether change is caused by true progression or by variability.  相似文献   

20.
Lack of diffuse loss of differential light sensitivity in early glaucoma   总被引:2,自引:0,他引:2  
We studied the differential light sensitivity in 83 patients who were prospectively followed with computerized threshold preimetry and optic disc pathography because of suspect glaucoma. Eyes with media opacities were excluded from the analysis. Fourteen eyes developed progressive optic disc cupping and/or localized visual field loss. In this glaucoma group light sensitivity in the 10 best points in the visual field did not deviate more from estimated age-corrected standard values than in the remaining groups of 115 eyes with increased intraocular pressure and 18 normotensive eyes. The results do not support the concept that diffuse loss of differential light sensitivity should be common in early glaucoma.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号