Video color perimetry: impairment in glaucoma suspects

Purpose: To detect mild visual field impairment in asymptomatic glaucoma suspect patients. Methods: Color perception within the visual field was tested with customized color video perimetry. The key features of the system were stimuli color desaturation, low-level luminance and equiluminant gray background. Twenty patients with asymptomatic glaucoma were tested and compared with a group of age-matched control subjects. Results: Automated perimetry test findings differed significantly in the two groups, particularly for short-wavelength sensitivity (blue). The severity of color impairment correlated directly with intraocular pressure. Conclusion: Desaturated low-luminance video perimetry will reliably detect and quantify asymptomatic visual field defects. A previous work on multiple sclerosis has detected a mild long-wavelength (red) impairment in asymptomatic patients after an episode of optic neuritis, even in clinically unaffected fellow eyes. Our findings in glaucoma suspect patients indicate that a mild blue impairment could be the initial sign of this disease.     

Comparing retinal sensitivities on blue-on-yellow and green-on-yellow perimetry in glaucoma suspects

Purpose:To compare the retinal sensitivities between the blue-on-yellow perimetry (BYP)/short-wavelength automated perimetry (SWAP) and green-on-yellow perimetry (GYP) among patients with and without nuclear sclerosis among glaucoma suspects.Methods:After ophthalmic examination, patients were subjected to two perimetric tests: BYP and GYP. The visual field (VF) parameters were compared between the two perimeters (p < 0.05 was considered significant).Results:Fifty-five eyes of 39 patients with a mean age of 60.53 ± 9.70 years were included in the study. Twenty-one eyes had clear lens or pseudophakia. Twenty-six eyes had lower grades of nuclear sclerosis (NO2NC2, NO3NC3) and eight eyes had higher grades of cataract (NO4NC4, NO5NC5). The mean retinal sensitivity (RS) in BYP was 22.08 ± 5.02 (dB) and in GYP was 23.84 ± 5.50 (dB) (p = 0.08). The mean defect in BYP was -2.56 ± 4.40 (dB) and in GYP was -3.24 ± 5.05 (dB), pattern standard deviation (PSD) in BYP was 3.65 ± 1.91 (dB) and in GYP was 3.83 ± 1.99 (dB), and foveal threshold (FT) was 24.20 ± 4.32 (dB) in BYP and 28.10 ± 4.50 (dB) in GYP. The two perimeters showed good agreement by the Bland–Altman plot for all parameters. Fourteen eyes showed perimetric changes suggestive of glaucoma by BYP. In these, GYP had a sensitivity of 92.86% (95% CI of 66.13% to 99.82%) and specificity of 95.12% (95% CI of 83.47% to 99.40%).Conclusion:BYP and GYP show good agreement. They are comparable in clear media as well as in different grades of nuclear sclerosis. GYP showed good sensitivity and specificity compared to BYP.     

Learning effect of Humphrey Matrix perimetry

BACKGROUND: Humphrey Matrix perimetry is a recent development in automated perimetry that uses frequency-doubling technology (FDT). We evaluated the learning effect of Humphrey Matrix perimetry with a full-threshold 30-2 strategy. METHODS: Twenty-four patients with primary open-angle glaucoma and early visual field defects as assessed by standard automated perimetry and 24 healthy control subjects participated. All subjects had no prior experience with FDT visual field tests. Humphrey Matrix perimetry using a full-threshold 30-2 strategy was performed 3 times within 1 month. Various visual field indices were compared across multiple tests. RESULTS: Mean deviation (MD) showed a larger defect at the first test than at the second and third tests (p < 0.001), and the mean total improvement of the MD was 2.80 decibels (dB) in the glaucoma group and 1.71 dB in the control group. Pattern standard deviations (PSDs) were decreased as the tests were repeated, but test duration, fixation losses, and false-positive or false-negative rate were not changed significantly. Additionally, the Glaucoma Hemifield Test (GHT) showed unstable results. INTERPRETATION: In patients naive to the FDT test, Humphrey Matrix perimetry showed a large learning effect on MD and PSD among the various visual field indices. The GHT results of Humphrey Matrix perimetry showed a large instability.     

Validating tablet perimetry against standard Humphrey Visual Field Analyzer for glaucoma screening in Indian population

Purpose:The aim of this study was to determine the correlation between the perimetric outcomes using a free application program of the iPad, ''Visual Fields Easy'' (VFE), and Humphrey Visual Field Analyzer (HVFA), in normal as well as eyes with glaucomatous damage of varying severity.Methods:In this prospective, cross-sectional, observational pilot investigation, visual field testing was carried out in 210 eyes of 210 patients (60 Normal, 150 Glaucoma), using suprathreshold VFE application (Version 8) on the iPad and Standard White-on-White using HVFA. Severity of glaucoma was categorized using Hodapp-Anderson-Parrish criteria for visual field defects. The results of the VFE program were compared to the 24-2 SITA FAST HVFA.Results:Data of 210 patients, 100 (47.6%) females, and 110 (52.4%) males, age ranging from 42 to 78 years, Mean 56.64 ± 10.67 years, was analyzed. The Spearman correlation coefficient showed a significant inverse relationship between missed points on the VFE app with MD (S = –0.783) and a parabolic relationship with PSD (S = 0.646) values obtained with the HVFA. As regards missed points, for mild glaucoma, missed points were 37.5, sensitivity was 77.8% and specificity was 52.6%; for moderate glaucoma, missed points were 33.5, sensitivity was 90% and specificity was 48% while for severe glaucoma, missed points were 23, sensitivity was 97% and specificity was 70%. AROC for eyes with mild glaucoma versus normal was 0.419 (95% CI: 0.343-0.495), moderate glaucoma versus normal was 0.705 (95% CI: 0.630-0.780) and severe glaucoma versus normal was 0.857 (95% CI: 0.806-0.908).Conclusion:Suprathreshold perimetry using VFE is not suitable as a rapid screening tool for mass screening of glaucoma. VFE cannot be used as a substitute for HVFA in clinic because of its inability to detect early or moderate glaucoma.     

Perimetry in Children: Survey of Current Practices in the United Kingdom and Ireland

Purpose: Visual fields are key functional outcome measures in children with a variety of ophthalmologic disorders. However, reliably assessing fields in children is challenging. We report the findings of a survey of current practices of perimetry in children in the United Kingdom and Ireland.

Methods: An electronic questionnaire was sent to Orthoptic Service Heads in July 2008.

Respondents were asked for comments regarding visual field testing in children as well as details of the volume and type of perimetry performed in their units, over a 1-year period.

Results: Of the 98 (62%) completed questionnaires, 16 departments reported not testing visual fields in children. In total 3675 subjects under 16 years of age were reported to have undergone perimetry in 1 year, most in units with a ≥ 50% pediatric caseload for orthoptics. A total of 42% of units used static perimetry alone, 11% kinetic, and 47% used a combination of both.

Conclusion: High numbers of visual field tests are carried out in children in the UK and Ireland annually. Automated perimetry is used predominantly, despite the underlying algorithms having been developed for adult populations. Thus there is a clear need for more research, to ensure that evolving management practices are informed by understanding of the diagnostic accuracy and value of perimetry in children.     

Comparison of diagnostic ability of standard automated perimetry,short wavelength automated perimetry,retinal nerve fiber layer thickness analysis and ganglion cell layer thickness analysis in early detection of glaucoma

Purpose:The aim of this study was to compare the diagnostic ability of macular ganglion cell layer (GCL) analysis using spectral domain optical coherence tomography against retinal nerve fiber layer analysis (RNFL), short-wavelength automated perimetry (SWAP), and standard automated perimetry (SAP) in early detection of glaucoma.Methods:Participants fulfilling the inclusion criteria were consecutively enrolled from the glaucoma clinic of tertiary care eye hospital in Western India from November 2015 to October 2016. The subjects underwent a detailed evaluation by trained glaucoma specialists. On suspicion of glaucoma, the patients underwent SAP, SWAP, and SD-OCT for GCL and RNFL analysis.Results:There were 91 patients in total of which experts classified 54 eyes into GON and 37 eyes into nonglaucomatous group. Sensitivity of SAP (42.59%) was significantly lower (P < 0.05) than that of average GCL thickness (79.63%) and average RNFL thickness (72.22%). Specificity and positive LR of SWAP (97.3% and 19.19, respectively) and SAP (94.6% and 7.88, respectively) were greater than those of GCL (81.08% and 4.21) and RNFL (67.57% and 2.23) parameters. Negative LR of average GCL thickness (0.25) was superior to that of average RNFL thickness (0.411), SWAP (0.495), and SAP (0.607).Conclusion:Macular GCL parameters perform better than RNFL parameters in patients with early glaucomatous damage. There is superior ability of SWAP over SAP in detecting glaucomatous changes in glaucoma suspect group. GCL thickness analysis has higher sensitivity and negative likelihood ratio, whereas SWAP had higher specificity and positive likelihood ratio. Thus, combining both tests can lead to better diagnostic ability for early glaucomatous damage.     

Evaluation of S-cone Sensitivity in Reattached Macula Following Macula-Off Retinal Detachment Surgery

Purpose To investigate the recovery of short-wavelength sensitivity in patients who had undergone successful reattachment of a rhegmatogenous retinal detachment with macular involvement.Methods Postoperative assessment of the visual acuity and the visual fields by standard achromatic automated perimetry (SAP), and short-wavelength automated perimetry (SWAP, Humphrey visual field analyzer; macula test pattern) was performed on 12 patients after the macula was reattached. The follow-up period was up to 12 months.Results The visual acuity and SAP sensitivity recovered rapidly after reattachment, with further moderate improvements up to 6 months after reattachment. The improvements stabilized by 9 to 12 months. The SWAP sensitivities improved more slowly than the visual acuity or SAP sensitivities, but they continued to improve even when visual acuity or SAP sensitivities had stabilized.Conclusion We conclude that measurement of the sensitivities of the short-wavelength-sensitive cones (S-cones) with SWAP may be a sensitive method to evaluate the visual recovery of the reattached macula following macula-off retinal detachment. Jpn J Ophthalmol 2005;49:301–305 © Japanese Ophthalmological Society 2005     

Recovery of Visual Field Loss Due to Central Retinal Artery Occlusion

Background The recovery of the visual field in eyes with central retinal artery occlusion (CRAO) has rarely been reported, because the patient has difficulty in central fixation during perimetry testing due to poor visual acuity. We describe the recovery of the central visual field in eyes with atypical CRAO.Cases Two patients who showed sudden visual loss underwent ophthalmic examinations, including fluorescein fundus angiography and Humphrey central 30-2 perimetry.Observations Both patients had good visual acuity at presentation, with normal retinal color in the area of the papillomacular bundle surrounded by a mild retinal whitening in one case and by scattered cotton-wool patches in the other. They were considered on the basis of angiographic findings to have central retinal artery occlusion. The mean deviation of the Humphrey central 30-2 perimetry gradually improved during the initial 70 days after the onset of symptoms in both patients.Conclusions Although the mechanism remains to be clarified, a certain degree of visual field recovery may be seen in some cases of retinal artery occlusion. More patients with CRAO should be studied with follow-up perimetry. Jpn J Ophthalmol 2004;48:294–299 © Japanese Ophthalmological Society 2004     

Factors influencing short wavelength automated perimetry in normal subjects

Background : Short wavelength automated perimetry (SWAP) has been shown to be useful in the early detection of visual field losses in glaucoma. This study investigates the effects of patient-related variables on SWAP. Methods : Eight normal subjects performed SWAP under a range of refractive blur conditions (plano, +1.00 D, +2.00 D, +3.00 D) and filter conditions (0.3 neutral density, yellow). Results : The results of this study were:

• 1 SWAP in normal subjects was unaffected by refractive blur up to +3.00D.
• 2 Filters produced an overall depression in SWAP sensitivity results proportional to their 400 nm transmission.

Conclusion : SWAP is a robust visual field test insensitive to moderate amounts of refractive error. However, as different visual mechanisms are being measured by the two tests, care should be taken when trying to compare SWAP directly with conventional white-on-white perimetry.     

Red flags and artifacts in perimetry

Background:As perimetry is a psychophysical test, the thresholds obtained are not only dependent on the functional architecture of the visual system but also on a variety of physical and cognitive factors. Factors such as, Lens rim artifact, improper refraction, miosed pupil and blepharoptosis, can affect luminance thresholds. Additionally, cognitive factors such as patient’s attention, motivation, fatigue, and response bias can influence the obtained thresholds.Purpose:The video describes identification of various artifacts in Humphrey visual field printout and it has some useful teaching points to recognize and learn.Synopsis:Visual field test is critical for assessment and to document progression of glaucoma, but is prone to errors and artifacts. Fortunately, the patterns of such artifactual field loss are often characteristic and easily recognizable.Highlights:Several types of errors can lead to inaccurate results. Proper instructions and patient supervision during the test helps to improve the test results. The technician should ensure correct patient’s data entry. Careful examination of the obtained data on the printout is essential to detect any errors that can lead to misinterpretation of visual field, false alarms, and wrong clinical conclusion.Video link: https://youtu.be/OWdFk4pWJkM     

Relationship between short-wavelength automatic perimetry and Heidelberg retina tomograph parameters in eyes with ocular hypertension

AIM:To compare and correlate optic nerve head parameters obtained byHeidelberg retina tomograph (HRT) with short-wavelength automatic perimetry (SWAP) indices in eyes with ocular hypertension (OHT).METHODS: One hundred and forty-six patients with OHT included in the present study. All subjects had reliable SWAP and HRT measurements performed within a 2wk period. The eyes were classified as normal/abnormal according to visual field criteria and Moorfields regression analysis (MRA). Correlations between visual field indices and HRT parameters were analyzed using Pearson correlation coefficient (r).RESULTS:Twenty-nine eyes (19.9%) had SWAP defects. Twenty-nine eyes (19.9%) were classified as abnormal according to global MRA. Six eyes (4.1%) had abnormal global MRA and SWAP defects. The k statistic is 0.116 (P=0.12) indicating a very poor agreement between the methods. No statistical significant correlation between HRT and SWAP parameters was detected.CONCLUSION:SWAP defects may coexist with abnormalities of optic disc detected by HRT in eyes with OHT. In most eyes, however, the two methods detect different glaucoma properties.     

分离格栅视觉诱发电位与蓝黄视野检查诊断开角型青光眼的性能比较

目的:评估分离格栅视觉诱发电位(IC-VEP)在诊断开角型青光眼中的表现,并将其与蓝黄色视野检查法(B/YP)和光学相干断层扫描(OCT)进行比较。方法:通过回顾性分析,对来自中国的101例受试者(正常组35例;早期青光眼30例,中晚期青光眼患者36例)分别进行IC-VEP、蓝黄色视野检查和OCT等检查。计算IC-VEP、视野检查法和OCT对检测青光眼的敏感度以及这三种方法之间的一致性,以评估其临床表现。结果:早期POAG组的IC-VEP、蓝黄色视野检查和OCT的敏感度分别为70.00%、70.00%、63.33%。在中晚期POAG组中,IC-VEP、OCT和蓝黄色视野检查的敏感度分别为86.11%、88.89%、91.67%。其中IC-VEP的特异性为91.43%。IC-VEP的结果与OCT和蓝黄色视野测试高度一致(kappa:0.721~1.000,P<0.05)。结论:作为视觉功能的客观检查手段,IC-VEP可用于青光眼的早期诊断,也可用于监测可疑青光眼患者的RGC功能。     

The association of office intraocular pressure fluctuation in ocular hypertension with frequency doubling technology perimetry abnormality

Purpose To characterize intraocular pressure (IOP) and central corneal thickness (CCT) measurements of ocular hypertension (OHT) patients with and without frequency doubling technology (FDT) perimetry test abnormalities. Patients and methods In this prospective, observational, cross-sectional, comparative case series, one eye of 33 OHT patients was randomly chosen. All OHT patients had IOP ≥23 mmHg in 2 out of 3 measurements on the test day, normal appearing discs and nerve fiber layer, and normal white on white standard automated perimetry (SAP). Several IOP calculations (outpatient IOP, highest office IOP, mean office IOP, office IOP fluctuation, and office IOP peak), CCT, SAP and FDT parameters were compared between OHT patients with repeatable FDT perimetry abnormality and normal FDT perimetry. Results Eight (24%) of 33 OHT patients had an abnormal FDT perimetry test. The median office IOP fluctuation (5.0 vs 2.0, P = 0.007), office IOP peak (3.2 vs 1.0, P = 0.004), and FDT pattern standard deviation (PSD) (5.03 v 3.32, P = 0.000) were significantly higher in OHT patients with repeatable FDT perimetry test abnormalities compared to OHT patients with normal FDT perimetry test. Office IOP fluctuation and office IOP peak were significantly correlated with both number of significantly depressed FDT points and FDT PSD index. CCT measurements and SAP global indices did not differ significantly in OHT patients with and without FDT perimetry test abnormality. Conclusion Our results suggest that currently diagnosed OHT patients who have large office IOP fluctuations and office IOP peaks are more likely to have repeatable FDT perimetry test abnormalities. These results suggest that OHT patients with large IOP fluctuations and IOP peaks are more likely to have early glaucomatous damage, and this should be taken into account when assessing the risk of conversion to primary open angle glaucoma.     

联合多种视功能检查对原发性开角型青光眼早期诊断的意义

了解原发性开角型青光眼视觉电生理和计算机自动视野检查结果的变化特征并对其视功能状况进行综合分析以寻找比较敏感和特异的参数，为原发性开角型青光眼较早期和早期诊断提供依据。方法：对３６例原发性开角型青光眼患者，８例可疑性青光眼患者，３０例正常对照者分别进行视网膜振荡电位，视网膜电图，视诱发电位和Ｈｕｍｐｈｅｒｙ计算机自动视野检查。     

A comparison of short wavelength automated perimetry with frequency doubling perimetry for the early detection of visual field loss in ocular hypertension

Background : Achromatic automated perimetry (AAP) is limited in its ability to detect very early visual field loss in ocular hypertensive patients. Tests targeting axons that are selectively damaged, or have low redundancy, may detect visual field losses before they are seen on AAP. It has been claimed that short wavelength automated perimetry (SWAP) and frequency doubling perimetry (FDP) are two tests that provide early detection. Methods : Patients (n = 62) were selected on the basis that they had raised intraocular pressure but normal visual fields detected by AAP. A SWAP and an FDP was performed on each of the patients and the results compared. Fields were scored as either normal or abnormal based on criteria used in previous studies. Results : On comparing FDP with SWAP as the ‘gold standard’, a sensitivity of 88.9% and a specificity of 96.2% was found, showing a high concordance between the two tests. Conclusion : These results suggest that as SWAP may be predictive of AAP visual field loss, FDP may be similarly predictive.     

Community Visual Field Screening: Prevalence of Follow-Up and Factors Associated With Follow-Up of Participants With Abnormal Frequency Doubling Perimetry Technology Results

Purpose: To determine if a community screening with Frequency Doubling Technology perimetry (FDT) results in a high proportion of follow-up with an eye care provider and the factors associated with follow-up. Design:Cross-sectional study. Setting: Telephone survey Methods: We conducted a telephone survey of participants with abnormal results 3–6 months after the community screening. Results: We were able to interview 121 participants (57% of 212 eligible subjects). Sixty-nine percent (83 of 121) of participants visited an eye care provider after the screening. Patients were more likely to attain an eye exam if they were female, older, or had an educational level of high school or more (p < 0.05). Of those participants who did not visit an eye care provider, 41% (18/38) did not believe the results of the test, 21% (8/38) reported not having insurance or an eye care provider, 11% (4/38) did not have time for an eye exam, and 11% (4/38) reported not knowing they needed to see an eye care provider. Conclusion: A community screening program with FDT encouraged more than two thirds of participants with abnormal results to seek an eye exam. The most common reason not to attain an eye exam was failing to recognize the importance of an abnormal test result.     

The Pupil Response to Large Regional Stimuli in Patients with Focal Visual Field Loss

Objective: To develop and use an intraocular analysis of the focal pupil response to large-sized, regional stimuli as a means of detecting areas of visual field loss. Patients and methods: A total of 42 normal subjects and 14 patients were tested with automated threshold perimetry and infrared pupillometry using computer-controlled, large-sized light stimuli (arcuate and quadrant shaped) at 10 apostilb intensity. These novel stimuli were presented (0.2 second duration) to different regions of the visual field of each eye. Each stimulus sequence was repeated 6 times. Results: A regional pupil deficit was detected in 7 of 12 eyes of 14 patients with visual dysfunction. The regional pupil response correctly corresponded to the visual field in 93 of 156 (60%) regions tested in the 14 patients. Conclusion: Detection of regional pupil deficits using large-sized light stimuli generally underestimates the degree of visual dysfunction as compared to automated threshold perimetry. One reason may be that retinal ganglion cells subserving the afferent pupillomotor pathway have larger receptive fields and greater spatial summation properties compared with those subserving the cortical visual pathway.     

Correlation of Afferent Pupillary Defect with Visual Field Loss on Automated Perimetry

The study was designed to ascertain the relationship between visual loss in the central 30° of vision and the density of the relative afferent pupillary defect (APD). The APD of 26 patients was quantified using a neutral log density filter. The mean threshold light sensitivity on Humphrey automated perimetry (Program 30-1) of one eye was subtracted from the fellow eye total to yield the interocular visual field difference (VFD). A direct correlation was noted such that the log density of the APD increased linearly with an increase in VFD (r = 0.69, P = 0.0001). In the absence of ptosis or ocular media opacification, a VFD greater than 8.7 that is not associated with an APD is suggestive of functional visual loss. Four patients had an APD despite normal static automated perimetry, indicating that an APD may be one of the earliest signs of retinal ganglion cell or axonal dysfunction.     

Localized scotomata detected with temporal modulation perimetry in central serous chorioretinopathy

Aim: Flicker deficits have been reported in various maculopathies, including age-related macular degeneration. We test whether flicker losses exist in patients with central serous chorioretinopathy (CSC) and whether the size and flicker frequency of the target is important in detecting such losses. Methods: We examined four CSC patients with temporal modulation (flicker perception) perimetry using the Medmont auto-flicker module (Medmont Pty Ltd, Melbourne, Vic. Australia), as well as static perimetry and colour vision. One case was examined using sophisticated laboratory equipment to precisely measure their temporal contrast sensitivity function (temporal CSF or de Lange curve) using larger targets to consider the effect of target frequency and size. Two patients were followed longitudinally and tested after resolution of the maculopathy. We compared our patients with an age-matched control group of 11 people. Results: Temporal modulation perimetry detected larger and more localized defects in all cases of active CSC compared with static perimetry. There appeared to be size and frequency tuning to the deficit, with greatest loss being found at 16 Hz with small (0.5°) targets. The losses resolved in one case where the retina recovered in 4 weeks, but remained to a lesser degree in another case who suffered a 2 year long fluctuating course before the CSC subsided. Conclusions: Temporal modulation perimetry detects a loss of flicker sensitivity in patients with CSC. Deeper and more clearly defined scotomata are found with a flickering stimulus compared with a steady state one. The greatest losses of flicker sensitivity are found with 16 Hz modulation and with small targets located directly over the lesion. The duration of the disease may be important for recovery of flicker sensitivity. Temporal modulation perimetry appears to be a valuable tool for the confirmation of functional loss due to CSC.     

Automated perimetry: background, instruments and methods

The goal of automated perimetry is to reduce perimetrist involvement and testing time while maintaining standardized test conditions. Proper calibration of the perimeter background luminance and target intensity is important so that results can be compared between examinations and machines. Three testing procedures may be used alone or in combination: kinetic, threshold static and suprathreshold static perimetry. The Octopus and the Perimetron are fully automated perimeters. The former uses threshold static perimetry while the latter uses kinetic and suprathreshold static perimetry. They are operated by small-sized microprocessors using miniature silicone chip circuitry. They are accurately calibrated, fulfilling the specifications deemed necessary by visual psychophysicists. Although data display and plotting problems still exist, automated perimetry is ready for thorough comparisons with Goldmann and Tübinger manual perimetry.