Frequency doubling technology perimetry for detection of glaucomatous visual field loss

PURPOSE:To evaluate the ability of frequency doubling technology perimetry to detect early, moderate, and advanced glaucomatous visual field loss.METHODS:In a prospective study, frequency doubling technology perimetry (C-20 full threshold) was performed in the right eye of 254 normal control subjects and 230 patients with early (n = 85), moderate (n = 114), or advanced (n = 31) glaucomatous visual field loss. Previous Humphrey Field Analyzer test results were used to classify glaucomatous visual field loss as early (mean deviation no worse than -6 dB), moderate (mean deviation between -6 and -12 dB) or advanced (mean deviation between -12 and -22 dB). RESULTS:Receiver operating characteristic curves showed 100% sensitivity and specificity (area under the curve, 1.0) for detecting advanced glaucomatous visual field loss, approximately 96% sensitivity and 96% specificity (area under the curve, 0.9751) for detecting moderate glaucomatous visual field loss, and approximately 85% sensitivity and 90% specificity (area under the curve, 0.9261) for early glaucomatous visual field loss.CONCLUSIONS:Frequency doubling technology perimetry demonstrates high sensitivity and specificity for detection of early, moderate, and advanced glaucomatous visual field loss.     

Frequency doubling technology perimetry for the detection of glaucomatous visual field loss

PURPOSE: To present an unusual case of orbital compartment syndrome after endoscopic sinus surgery. METHODS: Case report. RESULTS: Acute proptosis, chemosis, decreased vision, and ophthalmoplegia were found immediately after endoscopic sinus surgery. Ophthalmologic evaluation showed a tense orbit, and intraocular pressure increased to 54 mm Hg. Treatment was initiated and the intraocular pressure dropped. Computed tomography (CT) revealed the presence of bacitracin ointment in the orbit. CONCLUSION: Ophthalmic complications after sinus surgery are well identified. Postoperative orbital compartment syndrome may be caused by retrobulbar hemorrhage, edema, air (emphysema), or foreign material. In this case, the findings were caused by inadvertent injection of bacitracin ointment into the orbit.     

倍频视野计检测青光眼性视野缺损能力的研究

目的评估倍频视野计检测青光眼性视野缺损的能力以及与OCTOPUS101全自动视野计检查结果之间的相关性。方法应用倍频视野计的C-20—5筛选程序以及OC—TOPUS101全自动视野计的G2-TOP程序对23例正常对照者、20例早期青光眼患者、35例中晚期青光眼患者、11例高眼压患者及13例疑似青光眼患者进行视野检测。正常对照组、高眼压组及疑似青光眼组随机选择一眼进行测试，青光眼组选择具有较严重视野缺损的一眼进行测试。结果倍频视野计的C-20—5筛选程序在检测青光眼时ROC曲线下面积为0．925（敏感性85％，特异性91％），与OCTOPUS视野指数-平均缺损、偏离缺失之间的Pearson系数分别为0．702与0．429（P〈0．001），倍频视野计与OCTOPUS101视野计检查平均所需时间分别为1．00min与2．33min．2者之间有明显差异（P〈0．001）。结论倍频视野计检测青光眼性视野缺损具有良好的敏感性与特异性，与OCTOPUS101视野计的视野指数之间亦存在理想的相关性，而且前者比后者检测速度更快，使大规模人群筛查成为可能。     

Screening for glaucomatous visual field loss with automated threshold perimetry

We examined 27 glaucomatous eyes and 154 normal eyes with automated threshold perimetry. Previously suggested algorithms for detecting mild to moderate glaucomatous visual field loss, primarily by comparing the sensitivity of corresponding clusters of points above and below the horizontal meridian, yielded results remarkably consistent with those of our earlier series: 93% (25 of 27) of abnormal and 88% (135 of 154) of normal eyes were correctly identified. Excluding unreliable examinations increased specificity from 88% to 93%. Test duration was similar to results with the Field Analyzer's older, purportedly slower operating system.     

Automated differential threshold perimetry for detecting glaucomatous visual field loss

Because early glaucomatous visual field defects occur asymmetrically across the horizontal meridian, we analyzed data from automated perimetry by comparing sums of threshold values of corresponding groups of points in the superior and inferior hemispheres of the central 30 degrees tested by the Humphrey Field Analyzer. We developed patterns and criteria from 25 early glaucomatous and 36 normal control eyes to achieve optimal balance between sensitivity (96%) and specificity (86%). Application of these criteria to an independent group of 27 glaucomatous and 105 control eyes yielded a sensitivity of 88.9% and specificity of 85.7%. Minor modification of the criteria improved sensitivity and specificity to more than 90% for both patients and controls.     

多焦视诱发电位在青光眼视野损害检测中的应用

目的了解多焦视诱发电位(mfVEP)在青光眼视野损害检测中的作用。设计病例对照研究。研究对象 20例正常人和20例原发性青光眼患者。方法对20例正常人和20例原发性青光眼患者应用RETIscan mfVEP记录系统3．20行检查, 分别测量所有受试者mfVEP每一位点记录曲线的振幅,并计算受试者的双眼视网膜反应不对称系数(RAC)。比较青光眼患者 mfVEP检查的暗点与OCTOPUS 101型自动视野计G2程序检查的视野缺损区的对应性。主要指标振幅、RAC。结果在与自动视野计检查发现的视野缺损相对应的部位,90％患眼的mfVEP表现为至少3个相邻位点的振幅降低或RAC超出正常人数据库均数的2倍标准差(SD)。其中63％患眼表现为至少3个相邻位点的振幅降低超出正常人均数的2 SD,70％患眼表现为至少3个相邻位点的RAC超出正常人均数的2 SD。有2例患者(2眼)的自动视野计检查结果正常,但mfVEP显示有视野异常。正常人中无一眼的mfVEP表现为视野异常。结论 mfVEP有可能作为青光眼视野损害的客观检查手段。     

Clinical classification of glaucomatous visual field loss by frequency doubling perimetry

Purpose: To determine whether the frequency doubling perimeter (FDP) can grade glaucomatous visual function loss in a clinically relevant manner. Sinusoidal gratings <1 cpd that undergo counterphase flicker >15 Hz appear to have twice as many bands of light, a phenomenon referred to as the “frequency doubling illusion.” Evidence suggests that this psychophysical effect is mediated in part by large-diameter ganglion cells, which are reported to be lost early in the glaucomatous disease process. A portable, commercially available FDP has already demonstrated high diagnostic potential for glaucoma screening.Methods: Sixty-four eyes of 42 glaucomatous patients and 22 eyes of 14 normal subjects were evaluated by means of both frequency doubling perimetry and Humphrey perimetry. A clinical scoring algorithm modeled after the Hodapp-Parrish-Anderson criteria for scoring Humphrey visual field defects was derived for the FDP at the halfway point of the study, and all participants were reassessed with this algorithm upon its completion.Results: FDP mean and pattern deviation showed strong linear correlations with Humphrey 30-2 mean deviation (R = 0.75; P < .0001) and corrected pattern standard deviation values (R = 0.64; P < .0001). Despite this, neither global index could consistently categorize the graded glaucomatous visual fields in a manner consistent with the Hodapp-Parrish-Anderson criteria. The new FDP scoring algorithm did provide good segregation (73% precise parity, 93% parity within one Humphrey grade).Conclusions: Sixteen-zone frequency doubling perimetry can segregate glaucomatous visual field loss into pathologic categories approximating those obtained with Humphrey 30-2 perimetry by means of a formula modeled after the Hodapp-Parrish-Anderson criteria.     

倍频视野检查在青光眼视野缺损的应用

目的研究倍频视野检查在青光眼视野检查中的效果.方法应用倍频视野仪及Humphrey视野仪对64眼正常眼及120眼青光眼患者进行视野检查.结果倍频视野检查在青光眼视野检查中的特异性为55/64(85.9%),敏感性为104/120(86.7%).倍频视野检查在184眼正常眼及青光眼的视野检查中与Humphrey视野检查结果有密切相关(MD的相关系数为0.948,p＜0.001,PSD相关系数为0.712,p＜0.001).结论倍频视野检查是青光眼视野检查的一个有效手段.     

蓝/黄视野检查在预测青光眼视野变化的价值

目的　评价蓝 /黄视野检查法 (blue -on - yellow perimetry ,BYP)在预测青光眼视野缺损进展方面的价值。方法　对 1 6例原发性开角型青光眼 ( primaryopenangleglaucoma ,POAG)分别在同期内行BYP和白 /白视野检查法 (white -on -whiteperimetry ,WWP)检查 ,在同期视野检查后每年至少有 1次WWP随访检查。末次WWP检查与同期 2种视野检查的间隔时间为 1 7～ 4 0月 ,并分析WWP检查视野缺损进展情况。比较分析视野缺损进展组和未进展组的同期BYP和WWP检查的视野缺损点数和视野指数与视野缺损进展的关系。结果　 1 1例患者视野缺损无进展 ,5例患者视野缺损有不同程度的进展。进展组的BYP检查的缺损点数明显多于同期WWP检查的缺损点数 (t =4 .6 7,P =0 . 0 0 95) ;而未进展组 2种视野检查的缺损点数差异无显著性意义 (t =1 . 87,P =0. 0 91 2 ) ;BYP检查的平均敏感度 (meansensitivity ,MS)值均明显低于同期WWP检查的MS值 (P <0 . 0 5) ;BYP检查的平均缺损 (meandefect ,MD)值明显高于同期WWP检查的MD值 (P <0 . 0 5)。同期BYP和WWP视野缺损点数之比 ,进展组 ( 1 . 96± 0 .4 8)明显高于未进展组 ( 1 . 31± 0 . 4 0 ) ,两组间差异有显著性意义 (t =2 .85,P =0 . 0 1 2 9) ;同期BYP和WWP的MD值之比 ,进展     

Frequency doubling technology perimetry abnormalities as predictors of glaucomatous visual field loss

PURPOSE: To determine whether frequency doubling technology (FDT) perimetry results predict glaucomatous visual field defects, as assessed by standard automated perimetry (SAP), in a glaucoma suspect population. DESIGN: Longitudinal observational study. METHODS: The study included 105 eyes of 105 glaucoma suspect patients, with a mean follow-up time of 41 +/- 17 months. Glaucoma suspects had either intraocular pressure (IOP) higher than or equal to 23 mm Hg or glaucomatous optic neuropathy by stereophotograph assessment. All patients had normal SAP visual fields at baseline. A baseline FDT test was performed within 3 months of the normal SAP examination. Several baseline FDT parameters and other variables (age, gender, IOP, central corneal thickness, SAP visual field indices, and stereophotograph assessment) were investigated by univariate and multivariate Cox proportional hazards models to obtain hazard ratios (HR) and identify factors that predicted which patients had SAP glaucomatous visual field loss during follow-up. RESULTS: Seventeen patients (16%) developed repeatable SAP visual field abnormality during follow-up. An abnormal FDT examination at baseline predicted the development of SAP visual field conversion in both univariate (HR = 3.17; 95% confidence interval [CI] = 1.22-8.25; P =.018) and multivariate models (Adjusted HR = 3.68; 95% CI = 1.06-12.8; P =.04). The analysis of FDT examinations during follow-up revealed that in 59% of converters the FDT abnormalities preceded SAP visual field loss by as much as 4 years. Also, the initial development of glaucomatous visual field loss as measured by SAP occurred in regions that had previously demonstrated abnormalities on FDT testing. CONCLUSION: Functional abnormalities detected by FDT perimetry were predictive of the future onset and location of SAP visual field loss among glaucoma suspect patients.     

Diffuse and localized glaucomatous field loss in light-sense,flicker and resolution perimetry

A total of 75 eyes in 75 patients with different types of glaucoma (21 eyes with low-tension glaucoma, 49 with primary open-angle glaucoma and 5 with pigmentary glaucoma) were examined by automated light-sense, flicker and resolution perimetry. All fields were classified in a masked fashion as being normal (N) or as having diffuse loss (D), localized loss (L) or diffuse plus localized loss (DL). The frequency distributions for the various field loss categories were plotted against the highest intraocular pressure ever reported in the patients' records. The frequency distributions for the purely localized defects showed a peak at 20 mmHg and were markedly skewed to low pressure values, whereas those for both diffuse plus localized damage and purely diffuse loss peaked at about 30 mmHg. The data suggest that diffuse field loss may be an indicator of pressure-induced damage.This study was supported by research grant La517/2-1 (B.J.L.) from the German Research Foundation (Deutsche Forschungsgemeinschaft DFG, Bonn, F.R.G.) and by Medical Research Council of Canada grant 1578. Presented as a poster at the 1990 ARVO meeting in Sarasota, Florida     

Multifocal objective perimetry compared with Humphrey full-threshold perimetry in patients with optic neuritis

BACKGROUND: The aim of the study is to compare multifocal visual evoked potential (mfVEP) objective perimetry with Humphrey full-threshold visual field (HVF) perimetry, in the assessment of patients with optic neuritis (ON). METHODS: We assessed 16 patients with clinically diagnosed ON. A comparison was made between the HVF and mfVEP, based on the global severity indices of both tests and number and topography of significant abnormalities detected. The latency data and inter-eye asymmetry findings on the mfVEP were also evaluated. RESULTS: From a total of 128 quadrants analysed in the 16 patients (100 affected, 28 unaffected eyes), HVF perimetry identified a scotoma in 39/128 (30.5%) quadrants, all of which were in affected eyes; the mfVEP detected a scotoma in 68/128 (53.1%) quadrants using amplitude and/or asymmetry data (XV2=7.2485, P=0.0071). Latency plots on the mfVEP identified a significant latency deviation cluster in 20/25 (80%) affected eyes. Abnormalities were also detected in 4/7 (57%) unaffected eyes. The global severity indices in the affected eyes showed a high correlation between the two tests (r=0.73). CONCLUSIONS: The mfVEP detected more abnormalities in patients with ON than HVF perimetry. The use of latency recordings as well as combined amplitude and asymmetry plots is advantageous and has the potential to detect abnormalities not otherwise detected on HVF perimetry.     

Color perimetry of glaucomatous visual field defects

A color video tangent screen has been devised, using microcomputer control of a video display to produce colored perimetric test objects matched in luminance to a white surround at 10-foot lamberts . Perimetric isopters for varying degrees of color saturation were determined by kinetic perimetry. This form of color perimetry was used to examine one eye of each of 40 patients with open-angle glaucoma as well as 20 glaucoma-suspect patients. For the first 23 eyes with manifest glaucomatous visual field defects, a masked comparison was made between the results of color perimetry and conventional perimetry with a Goldmann perimeter. For these 23 eyes, color perimetry did as well as luminance perimetry in 14, was less sensitive in 2, and was more sensitive in 7. All defects that were detectable by conventional perimetry were successfully demonstrated by the color method. Such defects often appeared to be greater in extent when mapped by the color method as compared to conventional luminance perimetry.     

Blue-yellow perimetry in the detection of early glaucomatous damage

A perimetric method using blue stimuli on a yellow background was compared with perimetry using white stimulion on a white background as a method of detecting glaucomatous damage. Meridian perimetry was used with an adapted Tübinger perimeter. The difference between the blue-on-yellow meridian and the white-on-white meridian was subdivided into two parts: the general blue sensitivity loss (GBSL), probably due to optical factors, and the corrected blue sensitivity loss (CBSL), probably due to glaucoma. Nine normals, fourteen primary open angle glaucoma (POAG) patients and nine ocular hypertensives (OHT) were tested. All POAG patients and some of the OHT group showed higher CBSL values than the controls. The blue-yellow meridian showed broader and deeper defects than the white-white meridian in all of the POAG group; some of the OHT group had defects in the blue-yellow meridian that were not present in the white-white meridian.In conclusion, blue on yellow perimetry shows promise as a method for more sensitive detection of early glaucomatous damage.     

Short-wavelength automated perimetry can predict glaucomatous standard visual field loss by ten years

Examination of visual fields using standard achromatic automated perimetry (SAP) is essential for glaucoma management. However, as many as 35-50% of retinal ganglion cells can be lost before a visual field defect is detected.^1,2,3 Previous studies have indicated that examination of the short-wavelength (blue) sensitive color system may be able to detect early functional loss in glaucoma. Moreover, it has been reported to detect glaucomatous visual field loss as many as 5 years earlier than SAP.^4,5,6,7 We describe the case of a patient who demonstrated visual field defects on short-wavelength automated perimetry (SWAP) ten years prior to developing visual field defects in SAP.     

Short-wavelength automated perimetry can predict glaucomatous standard visual field loss by ten years

Examination of visual fields using standard achromatic automated perimetry (SAP) is essential for glaucoma management. However, as many as 35-50% of retinal ganglion cells can be lost before a visual field defect is detected. Previous studies have indicated that examination of the short-wavelength (blue) sensitive color system may be able to detect early functional loss in glaucoma. Moreover, it has been reported to detect glaucomatous visual field loss as many as 5 years earlier than SAP. We describe the case of a patient who demonstrated visual field defects on short-wavelength automated perimetry (SWAP) ten years prior to developing visual field defects in SAP.     

Variability of glaucomatous visual field defects in computerized perimetry

Summary Normal subjects are able to maintain a stable level of performance throughout a test session of 30 min, using 0.5 s exposure time. Test points placed in normal areas of glaucoma cases behave similarly, whereas test points in relative scotomatous parts of the field show not only a lower sensitivity level but also a tendency to a decline of the performance level and/or a higher threshold variation.Change of exposure time showed remarkable effects on the performance level at defect points, an increase to 1 s causing a stabilization on an improved level and a decrease to 0.25 s giving a deterioration.The results are discussed in terms of noise admixture to the signal. According to this model an increased noise amplitude by impaired retinal function reduces the performance level and augments the variation. On the other hand, an increased exposure time of the test object, which causes a stabilization of the process on an improved performance level, may be interpreted as a reduction of the noise amplitude.

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Zusammenfassung Gesunde Probanden zeigen bei der Perimetrie bis zu einer Untersuchungszeit von 30 min nur unbedeutliche Änderung der Schwellenwerte der Netzhautempfindlichkeit bei einer Darbietungszeit der Stimuli von 0.5 s Testpunkte im gesunden Gesichtsfeldbereich von Glaukompatienten verhalten sich ähnlich, während Testpunkte im Bereich relativer Gesichtsfeldausfälle nicht nur geringere sondern auch eine abnehmende Empfindlichkeit und/oder eine größere Variabilität der Schwellenwerte aufweisen.Eine Veränderung der Darbietungszeit zeigte einen erheblichen Effekt auf den Schwellenwerten bei relativen Skotomen; eine Zunahme der Darbietungszeit auf 1 s zeigte eine Stabilisierung auf erhöhter Empfindlichkeit, eine Abnahme der Darbietungszeit auf 0.25 s ergab eine starke Verschlechterung.Die Ergebnisse werden diskutiert unter dem Aspekt der Informationsübertragung unter Beimengung von Rauschen. Nach diesem Modell könnte eine vergrößerte Amplitude des Rauschens bei herabgesetzter Netzhautfunktion eine Verschlechterung des Schwellenwertes und die größere Variabilität bedingen. Anderseits kann die verlängerte Expositionszeit mit einer Stabilisierung des verbesserten Schwellenwertes als eine Reduzierung der Rauschen-Amplitude gewertet werden.

     

Quantification of glaucomatous visual field defects with automated perimetry

A method to quantify different glaucomatous visual field defects is presented. Three visual field indices are calculated: the short-term fluctuation, the mean defect, and the corrected loss variation. The method was applied to visual fields tested with program JO on the Octopus automated perimeter. The indices of 130 glaucoma suspects and 50 glaucoma patients were compared with 100 normal controls. The indices provide good detectability of visual field defects and easy follow-up.     

Detection of glaucomatous visual field defect by nonconventional perimetry

PURPOSE: To report the correlations among Humphrey Field Analyzer 750 (HFA), high-pass resolution perimetry (HRP), and frequency-doubling technology (FDT) perimetry in glaucoma patients and ocular hypertensive patients. DESIGN: Cross-sectional study. METHODS: Eighty-two eyes of 82 consecutive patients with primary open-angle glaucoma (POAG) or ocular hypertension were included in this study. One eye of each patient was randomly selected for data analysis. Visual fields were assessed by HFA, HRP, and FDT perimetry. HRP global deviation (HRP-GD), HRP local deviation (HRP-LD), FDT-mean deviation (FDT-MD), and FDT-pattern standard deviation (FDT-PSD) were considered for the analysis. Clinical agreement between HRP and FDT was evaluated. All data were analyzed by Pearson r coefficient when the distribution of the data was normal and by Spearman coefficient correlation when the distribution of the data was not normal. A P <.05 was considered statistically significant. RESULTS: Fifty-two eyes (52 patients) were classified as glaucoma and 30 eyes (30 patients) as ocular hypertension. In the entire group, a significant (P >.001) correlation was found between the HFA indices and those of either HRP or FDT. A significant (P <.001) correlation was found between HRP-GD and FDT-MD as well as between HRP-LD and FDT-PSD. In 14% of the glaucomatous patients and in 33% of the subjects with ocular hypertension, FDT and HRP showed different clinical features. CONCLUSIONS: Our data suggest that FDT and HRP are useful for detection of early glaucomatous visual field damage.