Measuring Visual Fields in Children With Glaucoma Using a Portable Tablet

Purpose

To compare perimetric outcomes of an iPad perimetry app (Melbourne Rapid Fields [MRF]) with those of the Humphrey Field Analyser (HFA) testing children with glaucoma.

Methods

Sixteen children diagnosed and treated for glaucoma were recruited to evaluate their perimetric performance over two visits. At each visit, they undertook visual field assessment using the MRF application as well as the HFA. The HFA test was part of their usual clinical work up and a clinical assistant judged which test format (24-2 SITA standard or SITA fast) might be suited to the testing of that child. The primary outcome measure was the association and repeatability of mean deviation (MD) for the MRF and HFA tests, by way of regression, intraclass correlation coefficient and Bland-Altman analysis. Secondary measures were comparisons of pattern deviation indices, test times as well as an indication of participant test preference. Summary data show means ± standard deviation.

Results

The age for our cohort was 7 to 15 years of age (mean, 10.0 ± 2.4 years of age). The MRF MD was in close concordance to HFA MD with an intraclass correlation coefficient of 0.91 (95% confidence interval, 0.82-0.95). Bland-Altman analysis found little bias (-0.6 dB) and a 95% coefficient of repeatability of 2.1 dB in eyes having a normal HFA MD. In eyes with glaucomatous visual field defects the 95% coefficient of repeatability at retest was much larger for both the MRF (10.5 dB) as well as for the HFA (10.0 dB). Average MRF test times (5.6 ± 1.2 minutes) were similar to SITA Fast (5.4 ± 1.9 minutes) with both being significantly faster than SITA standard (8.6 ± 1.4 minutes; P < 0.001). All children chose testing with the MRF as their preference.

Conclusions

MRF correlated strongly with HFA and was preferred by the children over the HFA. MRF is suitable for perimetric evaluation of children with glaucoma.

Translational Relevance

This study finds that an iPad based visual field test can be used with children having glaucoma to yield outcomes similar to SITA-fast. Children indicate a preference for such testing.

Kinetic Perimetry on Virtual Reality Headset

OBJECTIVE

We present a portable automatic kinetic perimeter based on a virtual reality (VR) headset device as an innovative and alternative solution for the screening of clinical visual fields. We compared the performances of our solution with a gold standard perimeter, validating the test on healthy subjects.

METHODS

The system is composed of an Oculus Quest 2 VR headset with a clicker for participant response feedback. An Android app was designed in Unity to generate moving stimuli along vectors, following a standard Goldmann kinetic perimetry approach. Sensitivity thresholds are obtained by moving centripetally three different targets (V/4e, IV/1e, III/1e) along 24 or 12 vectors from an area of non-seeing to an area of seeing and then transmitted wirelessly to a PC. A Python real-time algorithm processes the incoming kinetic results and displays the hill of vision in a two-dimensional map (isopter). We involved 21 subjects (5 males and 16 females, age range 22-73 years) for a total of 42 eyes tested with our proposed solution, and results were compared with a Humphrey visual field analyzer to test reproducibility and efficacy.

RESULTS

isopters generated with the Oculus headset were in good agreement with those acquired with a commercial device (Pearson's correlation values r > 0.83 for each target).

CONCLUSIONS

we demonstrate the feasibility of VR kinetic perimetry by comparing performances between our system and a clinically used perimeter in healthy subjects.

SIGNIFICANCE

proposed device leads the way for a portable and more accessible visual field test, overcoming challenges in current kinetic perimetry practices.

Glaucoma Home Monitoring Using a Tablet-Based Visual Field Test (Eyecatcher): An Assessment of Accuracy and Adherence Over 6 Months

Purpose

To assess accuracy and adherence of visual field (VF) home monitoring in a pilot sample of patients with glaucoma.

Design

Prospective longitudinal feasibility and reliability study.

Methods

Twenty adults (median 71 years) with an established diagnosis of glaucoma were issued a tablet perimeter (Eyecatcher) and were asked to perform 1 VF home assessment per eye, per month, for 6 months (12 tests total). Before and after home monitoring, 2 VF assessments were performed in clinic using standard automated perimetry (4 tests total, per eye).

Results

All 20 participants could perform monthly home monitoring, though 1 participant stopped after 4 months (adherence: 98% of tests). There was good concordance between VFs measured at home and in the clinic (r = 0.94, P < .001). In 21 of 236 tests (9%), mean deviation deviated by more than ±3 dB from the median. Many of these anomalous tests could be identified by applying machine learning techniques to recordings from the tablets' front-facing camera (area under the receiver operating characteristic curve = 0.78). Adding home-monitoring data to 2 standard automated perimetry tests made 6 months apart reduced measurement error (between-test measurement variability) in 97% of eyes, with mean absolute error more than halving in 90% of eyes. Median test duration was 4.5 minutes (quartiles: 3.9-5.2 minutes). Substantial variations in ambient illumination had no observable effect on VF measurements (r = 0.07, P = .320).

Conclusions

Home monitoring of VFs is viable for some patients and may provide clinically useful data.

Wide-field direct ocular straylight meter

The impact of the intraocular straylight (IOS) on the visual performance and retinal imaging is still a challenging topic. Direct optical methods to measure IOS avoid psychophysical approaches and interaction with the patient. In this work, we developed an optical instrument providing direct imaging measurement of IOS based on the double-pass technology. The system was tested in an artificial eye IOS model constructed with holographic diffusers and validated with theoretical simulations.

Accuracy of kinetic perimetry assessment with the Humphrey 850; an exploratory comparative study

AIM

To compare kinetic perimetry on the Humphrey 850 and Octopus 900 perimeters for assessment of visual fields, uniocular rotations and fields of binocular single vision.

METHODS

Prospective cross section study comparing Humphrey 850 kinetic perimetry to kinetic perimetry using the Octopus 900. Results were compared for both perimeters for the measurement of visual field boundaries, uniocular rotations and fields of binocular single vision in subjects with normal visual function, with comparisons of mean vector extremity values and duration of testing. A visual field boundary overlay was used to assess detection potential of Humphrey 850 kinetic perimetry using I4e and I2e targets in results of known abnormal visual fields.

RESULTS

Fifteen subjects (30 eyes) with normal parameters of visual function underwent dual perimetry assessment. Mean visual field boundaries and ocular rotation extremity values were similar for Humphrey and Octopus kinetic perimetry along horizontal meridians. Measurements for Humphrey perimetry were significantly smaller for superior and inferior visual field and rotations with ceiling effects at approximately 40 and 50 degrees, respectively. Use of visual field boundary overlays for 140 patient results showed high detection of the known abnormal visual field results by the Humphrey 850 perimeter (91.4% with I4e target; 95% with I2e target) but with notable exceptions for peripheral superior visual field defects.

CONCLUSIONS

The Humphrey perimeter's aspheric bowl introduces a ceiling effect for measurements in the superior and inferior visual field at approximately 40 and 50 degrees respectively. This results in potential diagnostic accuracy issues when measuring uniocular rotations, fields of binocular single and visual field boundaries in conditions that specifically impair superior and/or inferior ocular motility (e.g., thyroid eye disease) or visual fields (e.g., chiasmal compression).

Testing the visual field of children and adults with Rarebit: The role of task repetition on sensitivity

Rarebit is a simple and user-friendly perimetry that tests the visual field by using tiny supra-threshold dot stimuli. It appears to be especially useful for examining the visual field of children who are under 12 years of age. However, previous data showed that the number of errors was higher in children than adults. We ask whether the different number of errors in these two groups depended on task learning and whether it may be accounted for by sensitivity differences or a response bias. Thirty-one children between 9 and 12 years of age and thirty-nine adults were tested three times with Rarebit perimetry. A bias-free sensitivity index, d', rather than the simple hit rate, revealed a group difference that remained after extensive task repetition. Indeed, d' increased with task learning in a similar way in the two groups so that group difference remained after practice. The response bias differed in the two groups, being conservative in the older group (criterion C >0) and liberal in the younger (criterion C < 0). Both biases disappeared with task learning in the third session, suggesting that response bias cannot account for the group difference in sensitivity after practice. When bias-free measures of sensitivity are used and task learning effects are minimized, Rarebit perimetry may be a more valuable method than simple mean hit rate (MHR) to enlighten sensitivity differences in the visual field assessment within the pediatric population.

Computerized System for Static and Kinetic Automatic Perimetry

A new automatic perimeter has recently been developed under the supervision of the Perimetry Study Group of the Genoa University Eye Clinic. The main characteristics of this instrument are the following: projected targets; accurate calibration of stimulus size and shape; preliminary measurement of visual acuity and pupillary diameter; automated fixation control based on an optimized television system; static, kinetic, and mixed procedures; screening and diagnostic threshold and suprathreshold strategies; standard and non-standard parameters for stimuli, background, and procedures; user-friendly software; large disk memory for data storage and analysis.

Evaluating the Usefulness of MP-3 Microperimetry in Glaucoma Patients

PURPOSE

The purpose of the current study was to evaluate the test-retest reproducibility and structure-function relationship of the MP-3 microperimeter, compared against the Humphrey Field Analyzer (HFA).

METHODS

Design: Reliability and validity study.

SETTING

Institutional, or clinical practice.

STUDY POPULATION

Thirty eyes of 30 primary open-angle glaucoma patients were enrolled.

OBSERVATION PROCEDURES

Visual fields (VF) were measured twice with the MP-3 and HFA instruments, using the 10-2 test grid pattern in both perimeters. Ganglion cell complex (GCC) thickness was measured using optical coherence tomography (OCT). Test-retest reproducibility was assessed using the mean absolute deviation (MAD) measure at all 68 VF test points, and also the intraclass correlation coefficient (ICC) of the repeated VF sensitivities. The structure-function relationship between VF sensitivities (measured with MP-3 or HFA) and GCC thickness (adjusted for the retinal ganglion cell displacement) was analyzed using linear mixed modeling.

MAIN OUTCOME MEASURE

Reproducibility and structure-function relationship.

RESULTS

The average measurement duration with the HFA 10-2 was 7 minutes and 6 seconds (7m06s) ± 0m49s (mean ± standard deviation). A significantly (P < .001, paired Wilcoxon test) longer measurement duration was observed for the MP-3 test: 10m29s ± 2m55s. There were no significant differences in MAD and ICC values between HFA (MAD; 0.83 ± 0.69 dB and ICC: 0.89 ± 0.69, mean ± standard deviation) and MP-3 (MAD: 0.65 ± 0.67 dB and ICC: 0.89 ± 0.69). MP-3 VF sensitivities had a stronger structure-function relationship with GCC thickness compared to HFA.

CONCLUSIONS

The MP-3 microperimeter has a similar test-retest reproducibility to the HFA but a better structure-function relationship.

24-2 Visual Fields Miss Central Defects Shown on 10-2 Tests in Glaucoma Suspects, Ocular Hypertensives, and Early Glaucoma

PURPOSE

To investigate the prevalence of visual field defects in glaucomatous eyes, glaucoma suspects, and ocular hypertensives with 24-2 and 10-2 visual fields.

DESIGN

Prospective, cross-sectional study.

PARTICIPANTS

Patients with or suspected glaucoma tested with 24-2 and 10-2. Patients were classified into 3 groups on the basis of the presence of glaucomatous optic neuropathy (GON) and 24-2 visual field abnormalities: early glaucoma (GON and abnormal visual field, mean deviation >-6 decibels [dB]), glaucoma suspects (GON and normal visual field), and ocular hypertensives (normal disc, normal visual field, and intraocular pressure >22 mmHg). For the classification of visual field abnormalities, 24-2 and 10-2 tests performed on the same visit were analyzed.

MAIN OUTCOME MEASURES

Comparison of the prevalence of abnormal 24-2 versus 10-2 visual field results based on cluster criteria in each diagnostic group.

RESULTS

A total of 775 eyes (497 patients) were evaluated. A total of 364 eyes had early glaucoma, 303 eyes were glaucoma suspects, and 108 eyes were ocular hypertensives. In the glaucoma group, 16 of the 26 eyes (61.5%) classified as normal based on cluster criteria on 24-2 tests were classified as abnormal on 10-2 visual fields. In eyes with suspected glaucoma, 79 of the 200 eyes (39.5%) classified as normal on the 24-2 test were classified as abnormal on 10-2 visual fields. In ocular hypertensive eyes, 28 of the 79 eyes (35.4%) classified as normal on the 24-2 were classified as abnormal on the 10-2. Patients of African descent were more likely to have an abnormal 10-2 result (67.3 vs. 56.8%, P = 0.009).

CONCLUSIONS

Central visual field damage seen on the 10-2 test is often missed with the 24-2 strategy in all groups. This finding has implications for the diagnosis of glaucoma and classification of severity.

Performance of an iPad Application to Detect Moderate and Advanced Visual Field Loss in Nepal

PURPOSE

To evaluate the accuracy and efficiency of Visual Fields Easy (VFE), a free iPad app, for performing suprathreshold perimetric screening.

DESIGN

Prospective, cross-sectional validation study.

METHODS

We performed screening visual fields using a calibrated iPad 2 with the VFE application on 206 subjects (411 eyes): 210 normal (NL), 183 glaucoma (GL), and 18 diabetic retinopathy (DR) at Tilganga Institute of Ophthalmology, Kathmandu, Nepal. We correlated the results with a Humphrey Field Analyzer using 24-2 SITA Standard tests on 373 of these eyes (198 NL, 160 GL, 15 DR).

RESULTS

The number of missed locations on the VFE correlated with mean deviation (MD, r = 0.79), pattern standard deviation (PSD, r = 0.60), and number of locations that were worse than the 95% confidence limits for total deviation (r = 0.51) and pattern deviation (r = 0.68) using SITA Standard. iPad suprathreshold perimetry was able to detect most visual field deficits with moderate (MD of -6 to -12 dB) and advanced (MD worse than -12 dB) loss, but had greater difficulty in detecting early (MD better than -6 dB) loss, primarily owing to an elevated false-positive response rate. The average time to perform the Visual Fields Easy test was 3 minutes, 18 seconds (standard deviation = 16.88 seconds).

DISCUSSION

The Visual Fields Easy test procedure is a portable, fast, effective procedure for detecting moderate and advanced visual field loss. Improvements are currently underway to monitor eye and head tracking during testing, reduce testing time, improve performance, and eliminate the need to touch the video screen surface.

Smaller Fixation Target Size Is Associated with More Stable Fixation and Less Variance in Threshold Sensitivity

The aims of this randomized observational case control study were to quantify fixation behavior during standard automated perimetry (SAP) with different fixation targets and to evaluate the relationship between fixation behavior and threshold variability at each test point in healthy young participants experienced with perimetry. SAP was performed on the right eyes of 29 participants using the Octopus 900 perimeter, program 32, dynamic strategy. The fixation targets of Point, Cross, and Ring were used for SAP. Fixation behavior was recorded using a wearable eye-tracking glass. All participants underwent SAP twice with each fixation target in a random fashion. Fixation behavior was quantified by calculating the bivariate contour ellipse area (BCEA) and the frequency of deviation from the fixation target. The BCEAs (deg²) of Point, Cross, and Ring targets were 1.11, 1.46, and 2.02, respectively. In all cases, BCEA increased significantly with increasing fixation target size (p < 0.05). The logarithmic value of BCEA demonstrated the same tendency (p < 0.05). A positive correlation was identified between fixation behavior and threshold variability for the Point and Cross targets (ρ = 0.413–0.534, p < 0.05). Fixation behavior increased with increasing fixation target size. Moreover, a larger fixation behavior tended to be associated with a higher threshold variability. A small fixation target is recommended during the visual field test.

Visual Field Testing with Head-Mounted Perimeter 'imo'

PURPOSE

We developed a new portable head-mounted perimeter, "imo", which performs visual field (VF) testing under flexible conditions without a dark room. Besides the monocular eye test, imo can present a test target randomly to either eye without occlusion (a binocular random single eye test). The performance of imo was evaluated.

METHODS

Using full HD transmissive LCD and high intensity LED backlights, imo can display a test target under the same test conditions as the Humphrey Field Analyzer (HFA). The monocular and binocular random single eye tests by imo and the HFA test were performed on 40 eyes of 20 subjects with glaucoma. VF sensitivity results by the monocular and binocular random single eye tests were compared, and these test results were further compared to those by the HFA. The subjects were asked whether they noticed which eye was being tested during the test.

RESULTS

The mean sensitivity (MS) obtained with the HFA highly correlated with the MS by the imo monocular test (R: r = 0.96, L: r = 0.94, P < 0.001) and the binocular random single eye test (R: r = 0.97, L: r = 0.98, P < 0.001). The MS values by the monocular and binocular random single eye tests also highly correlated (R: r = 0.96, L: r = 0.95, P < 0.001). No subject could detect which eye was being tested during the examination.

CONCLUSIONS

The perimeter imo can obtain VF sensitivity highly compatible to that by the standard automated perimeter. The binocular random single eye test provides a non-occlusion test condition without the examinee being aware of the tested eye.

The Effect of Attentional Cueing and Spatial Uncertainty in Visual Field Testing

Purpose

To determine the effect of reducing spatial uncertainty by attentional cueing on contrast sensitivity at a range of spatial locations and with different stimulus sizes.

Methods

Six observers underwent perimetric testing with the Humphrey Visual Field Analyzer (HFA) full threshold paradigm, and the output thresholds were compared to conditions where stimulus location was verbally cued to the observer. We varied the number of points cued, the eccentric and spatial location, and stimulus size (Goldmann size I, III and V). Subsequently, four observers underwent laboratory-based psychophysical testing on a custom computer program using Method of Constant Stimuli to determine the frequency-of-seeing (FOS) curves with similar variables.

Results

We found that attentional cueing increased contrast sensitivity when measured using the HFA. We report a difference of approximately 2 dB with size I at peripheral and mid-peripheral testing locations. For size III, cueing had a greater effect for points presented in the periphery than in the mid-periphery. There was an exponential decay of the effect of cueing with increasing number of elements cued. Cueing a size V stimulus led to no change. FOS curves generated from laboratory-based psychophysical testing confirmed an increase in contrast detection sensitivity under the same conditions. We found that the FOS curve steepened when spatial uncertainty was reduced.

Conclusion

We show that attentional cueing increases contrast sensitivity when using a size I or size III test stimulus on the HFA when up to 8 points are cued but not when a size V stimulus is cued. We show that this cueing also alters the slope of the FOS curve. This suggests that at least 8 points should be used to minimise potential attentional factors that may affect measurement of contrast sensitivity in the visual field.

Comparison of Standard Automated Perimetry, Short-Wavelength Automated Perimetry, and Frequency-Doubling Technology Perimetry to Monitor Glaucoma Progression

Detection of progression is paramount to the clinical management of glaucoma. Our goal is to compare the performance of standard automated perimetry (SAP), short-wavelength automated perimetry (SWAP), and frequency-doubling technology (FDT) perimetry in monitoring glaucoma progression.Longitudinal data of paired SAP, SWAP, and FDT from 113 eyes with primary open-angle glaucoma enrolled in the Diagnostic Innovations in Glaucoma Study or the African Descent and Glaucoma Evaluation Study were included. Data from all tests were expressed in comparable units by converting the sensitivity from decibels to unitless contrast sensitivity and by expressing sensitivity values in percent of mean normal based on an independent dataset of 207 healthy eyes with aging deterioration taken into consideration. Pointwise linear regression analysis was performed and 3 criteria (conservative, moderate, and liberal) were used to define progression and improvement. Global mean sensitivity (MS) was fitted with linear mixed models.No statistically significant difference in the proportion of progressing and improving eyes was observed across tests using the conservative criterion. Fewer eyes showed improvement on SAP compared to SWAP and FDT using the moderate criterion; and FDT detected less progressing eyes than SAP and SWAP using the liberal criterion. The agreement between these test types was poor. The linear mixed model showed a progressing trend of global MS overtime for SAP and SWAP, but not for FDT. The baseline estimate of SWAP MS was significantly lower than SAP MS by 21.59% of mean normal. FDT showed comparable estimation of baseline MS with SAP.SWAP and FDT do not appear to have significant benefits over SAP in monitoring glaucoma progression. SAP, SWAP, and FDT may, however, detect progression in different glaucoma eyes.

Heidelberg Edge Perimeter: The New Method of Perimetry

Glaucoma is an optic nerve neuropathy associated with progressive visual field loss. One of the most frequent eye diseases these days, it is believed to have affected 60 million people worldwide in 2014. Various visual field examination methods are known, from the confrontational test to kinetic and static perimetry. The latest device to access the visual field is the Heidelberg Edge Perimeter (HEP). It is a flicker perimeter, but, unlike others of its kind, it uses a unique stimulus called FDF (Flicker Defined Form). A 5-grade round stimulus is created by reversing the phase of flickering black and white dots, thereby forming illusory outlines. The test uses randomly flickering points in medium illumination (50 cd/m²). The background remains the same during the whole test. Background luminance is 50 cd/m2, the marker showing time is 400 ms, and the frequency is 15 Hz. Current studies show that HEP can detect early visual field loss which remains invisible during a standard visual field test with standard automated perimetry. HEP might also prove useful in the early detection of other diseases connected with visual field loss, for example in neurology.

Correcting LCD luminance non-uniformity for threshold Saccadic Vector Optokinetic Perimetry (SVOP)

The accurate assessment of visual field function can provide valuable information on a range of visual disorders. Saccadic Vector Optokinetic Perimetry (SVOP) is a novel instrument for measuring supra-threshold visual fields in young children who are otherwise unable to perform Automated Static Perimetry (ASP). However, limitations in Liquid Crystal Display (LCD) technology restrict the ability of SVOP to determine threshold values at various points in the visual field, often required in detailed perimetry examinations. This paper introduces a purpose-specific LCD luminance non-uniformity compensation approach to address this limitation. Thorough quantitative evaluation identifies the effectiveness of the proposed approach in (i) compensating for luminance non-uniformities across an LCD, and (ii) enabling SVOP to perform accurate and precise threshold visual field tests. The findings demonstrate that SVOP provides a promising alternative to the current threshold ASP standard (Humphrey Field Analyser).

Early detection of choroidal neovascularization facilitated with a home monitoring program in age-related macular degeneration

PURPOSE

To describe clinical and imaging findings in two eyes with new onset subtle neovascular age-related macular degeneration that was detected by the regular use of a home monitoring device based on preferential hyperacuity visual field testing.

METHODS

Interventional case report.

RESULTS

Case 1, an 82-year-old man with the intermediate stage of age-related macular degeneration in both eyes, had been using the ForeseeHome device for 2 years when a change in test scores prompted an examination (an alert visit) to search for choroidal neovascularization (CNV) in his right eye. He denied any vision changes, and visual acuity remained 20/20 in the right eye. Fundus examination showed large drusen without any signs of CNV. The late phase of a fluorescein angiogram showed a small juxtafoveal area of subretinal leakage which corresponded to an intraretinal cystoid abnormality on optical coherence tomography. Intravitreal ranibizumab therapy was initiated, and the patient has maintained excellent visual acuity for at least 1 year. Case 2, a 67-year-old woman, had been using the home device for 3 months when an alert notification was prompted in the left eye. On notification, she recognized that she had had a subtle change in her vision in that eye with new distortion. Visual acuity decreased to 20/32 in the left eye. Fundus examination revealed stable confluent drusen without any apparent fluid, blood, or lipid. No definite fluorescein angiogram leakage was identified among the hyperfluorescent staining of extensive drusen. However, optical coherence tomography showed a cystoid abnormality in the inner plexiform layer prompting the initiation of intravitreal ranibizumab under the assumption that the changes represented CNV.

CONCLUSION

The home monitoring device has been proven to facilitate early detection of CNV associated with age-related macular degeneration. These two cases highlight early diagnosis of CNV heralded by the device. Visual acuity remained 20/32 or better, minimal or no fluorescein angiogram leakage was found, and subtle cystoid abnormalities appeared on optical coherence tomography.

Development and evaluation of a new instrument to measure visual exploration behavior

Effective visual exploration is required for many activities of daily living and instruments to assess visual exploration are important for the evaluation of the visual and the oculomotor system. In this article, the development of a new instrument to measure central and peripheral target recognition is described. The measurement setup consists of a hemispherical projection which allows presenting images over a large area of ± 90° horizontal and vertical angle. In a feasibility study with 14 younger (21-49 years) and 12 older (50-78 years) test persons, 132 targets and 24 distractors were presented within naturalistic color photographs of everyday scenes at 10°, 30°, and 50° eccentricity. After the experiment, both younger and older participants reported in a questionnaire that the task is easy to understand, fun and that it measures a competence that is relevant for activities of daily living. A main result of the pilot study was that younger participants recognized more targets with smaller reaction times than older participants. The group differences were most pronounced for peripheral target detection. This test is feasible and appropriate to assess the functional field of view in younger and older adults.

[Practical aspects of automated perimetry]

Visual field testing is a subjective method, but yet a very important part for diagnosis and in follow-up of ocular or neurological diseases. In order to do a correct exam of the visual field, one must know well the equipment and all the factors that could induce errors. Basic skills for working with Optopol or Humphrey perimeter are discussed in this paper.

[Pulsar perimetry. A review and new results]

We present a review and update on Pulsar perimetry, which combines temporal frequency, contrast and spatial frequency stimuli. The effects of age, visual acuity, and learning on results are described. Data on threshold fluctuation, signal-to-noise ratio, and the possibility of reducing noise with filtering techniques are provided. We describe its dynamic range and the possibility of compensating for profound defects. Finally, we show the results obtained in normal patients and in those with ocular hypertension or initial glaucoma, as well as an analysis of glaucoma progression.

Visual automated macromolecular model building

Automated model-building software aims at the objective interpretation of crystallographic diffraction data by means of the construction or completion of macromolecular models. Automated methods have rapidly gained in popularity as they are easy to use and generate reproducible and consistent results. However, the process of model building has become increasingly hidden and the user is often left to decide on how to proceed further with little feedback on what has preceded the output of the built model. Here, ArpNavigator, a molecular viewer tightly integrated into the ARP/wARP automated model-building package, is presented that directly controls model building and displays the evolving output in real time in order to make the procedure transparent to the user.

[Different significance in normal subjects and in glaucoma patients tested with Optopol PTS-910, in the galucoma program]

PURPOSE

to quantify the inter-test variability (dB) for the Optopol PTS automated perimeter, Glaucoma Fast threshold program.

MATERIALS AND METHOD

A prospective study was performed on 166 glaucomatous patients and a control group of 30 normal subjects, tested by complete ophthalmological exam and automated perimetry (Optopol PTS-910). The visual field was tested weekly for 4 consecutive weeks. The visual field defects were classified according to the Aulhorn-Karmeyer descriptive scale.

RESULTS

For the control group, the medium inter-test variability was of 1.57 +/- 0.24 dB, lower next to fixation and increasing towards the 50 degree isopter. The medium inter-test variability increases along with the perimetric stage :1.57 +/- 0.66 dB for pre-perimetric glaucoma, 2.13 + 1.04 dB for non-specific defects group, 3.23 + 1.01 dB for the stage 1, 3.52 + 2.61 dB, for the stage 2, 3.65 + 1.19dB for the stage 3 and 5.82 +/- 1.67dB for the stage 4. For the cases of preperimetric glaucoma and non-specific defects, a similar profile of variability to the normal subjects can be observed. For the stages 2-4, the profile of the areas with maxim inter-test variability moves towards the relative scotoma and the surrounding area.

CONCLUSIONS

A better description of the inter-test variability and the evolution of this intricate parameter of the retinal light sensitivity is useful for the differential diagnostic between the real change and the "background noise" in early detection of the functional progression in glaucoma.

Glaucoma diagnosis optic disc analysis comparing Cirrus spectral domain optical coherence tomography and Heidelberg retina tomograph II

PURPOSE

To evaluate the diagnostic ability of optic nerve head parameters, measured by Cirrus spectral domain optical coherence tomography (SD OCT) and Heidelberg retina tomograph II (HRT II) to detect concomitant glaucoma.

METHODS

Cirrus OCT and HRT examinations of 62 eyes of 62 patients (32 with no perimetric glaucoma and 30 with concomitant perimetric glaucoma) evaluated between August 2010 and December 2010 were retrospectively analyzed and compared with regard to the optic disc morphometric parameter, disc area, rim area, cup-to-disc ratio (CDR), and cup volume. Receiver operating characteristic curves were constructed for the parameters and areas under the curves (AUCs) were compared.

RESULTS

All parameters except disc area were significantly different between Cirrus OCT and HRT. Average cup-to-disc ratio (CDR), vertical CDR, and cup volume were greater when measured by OCT compared with HRT II (P = 0.002, P < 0.001, and P < 0.001, respectively). Rim area was smaller by OCT than by HRT II (P < 0.001). Of the parameters evaluated, rim area (0.938), average CDR (0.865), and vertical CDR (0.897) had higher AUCs with OCT than with HRT II. Glaucoma diagnostic capability using the AUC was greater for OCT than for the HRT.

CONCLUSIONS

Optic nerve head parameters measured by Cirrus OCT seem to be useful in differentiating glaucomatous optic nerve heads. The two types of instrument compared here should not be used interchangeably to obtain measurements of the optic disc for diagnosis of glaucoma.

[Comparison between binocular, open-field auto ref/keratometer and conventional autorefractor]

OBJECTIVE

To compare the refractive results between open-field auto ref/keratometer and conventional autorefractor, and to investigate the effect of cycloplegic to this difference.

METHODS

Three hundred and four primary and secondary school students were consecutively enrolled in Beijing Tongren Hospital. Non-cycloplegic and cycloplegic objective refractions were performed for each subject by conventional autorefractor (Accuref-K9001, Shin Nippon, Japan) and binocular, open-field auto ref/keratometer (Grand Seiko Co., Ltd., Hiroshima, Japan). The coincidence rate of sphere, spherical equivalent (SE) and axis (defined as difference of diopter ≤ 0.50 D, difference of axis degree ≤ 20°) were calculated; Bland-Altman and distribution analysis were performed according to mean and difference of SE.

RESULTS

The coincidence rate of sphere, SE and axis were 77.3%, 78.6% and 66.0% before cycloplegic and increased to 94.4%, 95.1% and 69.5% after cycloplegic, respectively. The difference (95%CI) of SE before cycloplegic between these two refractometers was 0.12 (-1.04 to 1.29) D and was positively correlated with the mean of SE (after cycloplegic) (r(pearson) = 0.21, P < 0.001). The difference (95%CI) of SE after cycloplegic was -0.08 (-0.60 to 0.45) D. The difference (95%CI) of SE of K9001 autorefractor before and after cycloplegic was larger than that of WAM autorefractor [0.51 (-0.83 - 1.84) D and 0.31 (-0.66 to 1.28) D, P < 0.001]. Before cycloplegic, SE measured by WAM autorefractor showed myopic more than 0.25 D than K9001 (group 1) was found in 51 (16.8%) subjects; difference within 0.25 D was found in 160 (52.6%) subjects; hyperopic more than 0.25 D (group 3) was found in 93 (30.6%) subjects. After cycloplegic, 69 (22.7%) subjects were found in group 1, and subjects increased to 213 (70.1%) and decreased to 22 (7.2%) in group 2 and group 3, respectively.

CONCLUSION

The binocular, open-field auto ref/keratometer provides more hyperopic readings than conventional autorefractor. It will be useful in both clinical screening and scientific research because it produces less instrument myopia than that of conventional autorefractor.

[Design and implementation of pupil auto-tracking system in the perimeter]

The pupil auto-tracking system is a key component of the full-automatic perimeter. Taking the advantage of integral image in counting characteristic value rapidly, we studied the relationship between training stages and total error detection rate based on the training of Adaboost strong classifier. Besides, a testing strategy of amplification detection window was introduced, and a multi-stage cascaded eye classifier for eye detection was proposed finally. It kept the same detection rate as the commonly trained strong classifier with a much lower error detection rate. In the meantime, the present article explaines the main arithmetic implement functions, as well as designs the motion control program for the jaw bracket system.

[Correlation between visual field index values and mean deviation values of Humphrey field analyzer]

PURPOSE

We examined the correlation between the visual field index (VFI) and mean deviation (MD), as well as the correlation on VFI slope and MD slope.

METHODS

This retrospective study was performed on 105 eyes of 60 patients. All eyes underwent examination by the Humphrey visual field analyzer. The correlation of the (i) VFI and MD, (ii) VFI slope and MD slope were analyzed in all eyes and the eyes were classified by visual field patterns (paracentral, peripheral, mixed and normal defect type). (iii) The agreement degree between the VFI slope and MD slope was examined. A generalized-estimating-equation(GEE) model and kappa statistic were used for analysis.

RESULT

A significant correlation between MD and VFI was shown in all eyes, including eyes classified of visual field defect. The correlation between the VFI slope and MD slope was significant in all eyes. However, these correlations were not evident in paracentral type of defect but in the other types. K statistic evaluated a moderate agreement between the VFI slope and MD slope.

CONCLUSION

A significant correlation was shown between the VFI and MD, VFI slope and MD slope in all eyes. However, no correlation between the VFI slope and MD slope existed in the paracentral area. It seems that the evaluation of progression of visual field defect in the central area needs to be considered carefully.

Perimetry, tonometry and epidemiology: the fate of glaucoma management

This is the lecture that I gave when I was awarded Acta Ophthalmologica's gold medal and honorary award at the Nordic Ophthalmological Congress in Reykjavik in August 2010. I was inspired by Jared Diamond's famous book: Guns, Germs, and Steel, The Fates of Human Societies. Diamond is professor of geography and physiology at the University of California, Los Angeles. In this book, which won the Pulitzer Prize, the author explains why the European civilization took over the world. This was all because of predetermined factors of biological nature, environmental differences that were strengthened by feedback loops, and resulted in technological innovation and superiority. In this presentation, I write about the development of glaucoma knowledge and management. I suggest that the development might have been predetermined, just waiting for more facts to be unveiled by research. The technologies tonometry and perimetry have been fundamental as has epidemiological techniques and controlled trials. The new and increased knowledge about glaucoma must now be translated to improvements of clinical glaucoma care. The glaucoma scientists of today and tomorrow will continue to reveal as yet unknown facts, maybe in a predetermined way, but nevertheless of benefit to all patients with glaucoma.

[Comparing the ranges of defect measured with standard white on white and Pulsar perimetries]

OBJECTIVES

Normal thresholds on Pulsar perimetry fall faster than those of standard perimetry in the peripheral visual field. Two related studies were performed. Firstly, the frequency distributions of glaucoma defects on standard automated perimetry (SAP) and the relationship of the centre and periphery (Study A) were studied first, followed by an attempt to establish the limits of pulsar perimetry (Study B).

MATERIAL AND METHOD

A: frequency of defects was calculated in 78.663 SAP perimetries (G1-TOP, Octopus 1-2-3, Haag-Streit). Study B: 204 eyes with mean defect (MD-SAP) lower than 9 dB were examined 8.92 ± 4.19 times with SAP (TOP-32, Octopus 311) and temporal modulation perimetry (T30W, Pulsar Perimeter, Haag-Streit).

RESULTS

Study A: 50.7% of the SAP examinations showed MD values lower than 9 dB and 32.7% bellow 6 dB. The MD correlation of the central 20° with the MD of the most peripheral points was r=0.933. Study B: in cases with MD-TOP-32 lower than 6 dB, SAP had the maximum possibility of detecting defect in 0.02% of points and Pulsar in 0.29%. In subjects with MD-TOP-32 between 6 and 9 dB frequencies were 0.38% in SAP and 3.5% in Pulsar (5.1% for eccentricities higher than 20°).

CONCLUSIONS

Pulsar allows detecting defects, without range limitations, in the initial half of SAP frequencies expected on glaucoma patients. In order to study the progression of deeper defects the examination should focus on the central points, where the dynamic range of both systems is more equivalent.

[Application of Octopus 101 automated perimetry with kinetic and static program in patients with the anterior ischemic optic neuropathy]

OBJECTIVE

To investigate the clinical significance of the Octopus 101 kinetic and Static combined automatic perimetry in Anterior Ischemic Optic Neuropathy (AION). To assess the merit and demerit of Octopus 101 kinetic and static combined automatic perimetry performed in AION cases.

METHODS

45 AION patients were detected with Octopus 101 with kinetic and static 30 degrees, 60 degrees scope static program from June 2006 to September 2008. The mean defect (MD), loss variance (LV), areas of isopter, and reaction time were analyzed. The correlation between MD, areas of isopter and reaction time were analyzed.

RESULTS

In AION, there are kinds of visual field defect related to the optic lesions in static perimetry examine. Kinetic programme display the isopter deletion. Isopter areas using I-2e and III-4e stimulus are significantly different (P < 0.05). Smaller stimulus can find more periphery changes in AION.

CONCLUSIONS

The Octopus 101 perimeter can provide static and kinetic program in the same sitting. In clinical practice it is necessary to perform both static and kinetic examination in patients with AION because the visual field defects are diverse, and the data provided by static and kinetic program are complementary.

Comparison of static automated perimetry and semi-automated kinetic perimetry in patients with bilateral visible optic nerve head drusen

PURPOSE

Until now there has been no standardized, systemic approach to diagnostics in patients with optic nerve head drusen (ONHD). This study compares visual field (VF) results obtained with static automated perimetry (SAP) and semi-automated kinetic perimetry (SKP) in patients with bilateral visible ONHD.

METHODS

Visual fields in 26 eyes (13 patients) with ONHD were obtained by Humphrey Field Analyser II (SAP) and Octopus 101 (SKP) equipment and classified by three masked observers. Pairs of VFs were considered equivalent if the descriptions given by both methods matched. Individual reaction time (RT) was assessed during SKP. Fifteen healthy volunteers were examined as control material.

RESULTS

Visual field pairs matched in 19 eyes (three normal VFs, 16 arcuate defects). In the remaining eight eyes SKP provided more information in concentric constriction of the VF (two eyes) and SAP provided more information on paracentral scotomas (five eyes). Sensitivity was 69% for SKP, 80% for SAP and 88% for both methods together. Mean RT assessed using SKP amounted to 909 ms in eyes with ONHD and 568 ms in normal subjects (p < 0.0003). The median examination duration was 13 mins with SKP and 11 mins with SAP (p = 0.05) in eyes with ONHD, and 8 mins in control eyes (p < 0.0001).

CONCLUSIONS

In clinical practice it is necessary to perform both SAP and SKP in patients with ONHD because the VF defects are diverse. In SKP, RT is prolonged in eyes with ONHD compared with normal eyes and SKP takes longer than SAP in ONHD eyes.

Computerized meridian perimetry. A preliminary report

By a modification of the display of test points it is possible to use the computerized perimeter "Competer" for meridian testing. The test program gives estimates of the thresholds in two separate rounds, the second starting when the first is completed. Accordingly two profiles are plotted in the meridians tested. Furthermore a smoothed profile is drawn from the mean values of the two rounds. The outcome when testing normal subjects and cases with glaucomatous defects was studied and the stability of thresholds in normals and the decay in scotomatous areas with time is demonstrated.

Evaluation of the oculo-kinetic perimetry glaucoma screening test in a sub-Saharan African setting

BACKGROUND

The oculo-kinetic perimetry glaucoma screening test (OKPGST) simplifies testing for glaucoma. Despite its acceptable degree of efficiency and practicability, its usage in sub-Saharan African appears limited.

OBJECTIVE

To evaluate and compare the oculo-kinetic perimetry glaucoma screening chart against automated perimetry and clinical criteria in screening for glaucoma in a sub-Sahara African setting.

METHODS

In the first stage, the test was conducted on selected eyes with reproducible glaucomatous visual field detects on perimetry with the KOWA AP125 central visual field plotter, and also in their age-matched controls. During the second stage at the rural outreach health posts, patients with clinically diagnosed primary open angle glaucoma (intraocular pressure of > 21mmHg and a cup/disc ratio > 0.5), and their age-matched controls were also screened with the test.

RESULTS

The test was positive in 107 of the 113 eyes with glaucomatous field loss on automated perimetry; and inaccurate in 2 of the 98 control eyes, giving a sensitivity of 94.7%, specificity of 98%, and an efficiency of 96.2%. Among patients with clinically diagnosed glaucoma at the rural health posts, the test was positive in 61 of 65 eyes, while it was inaccurate in 2 of 62 eyes of control patients, giving a sensitivity of 93.8%, specificity 96.8%, and an efficacy of 99.2%.

CONCLUSION

The oculo-kinetic perimetry glaucoma screening test with the KOWA performed well, using the KOWA automated perimeter as a standard. It is a convenient, rapid, reliable and inexpensive screening tool in diagnosing primary open angle glaucoma in rural health establishments where conventional perimeters are lacking.

Age-dependent normative values for differential luminance sensitivity in automated static perimetry using the Octopus 101

PURPOSE

To determine age-dependent normative differential threshold values for the Octopus 101 instrument and to create a smooth mathematical model characterizing the age-dependency and asymmetry of the hill of vision.

METHODS

Static automated perimetry within the central 30 degrees visual field (VF) was conducted with the Octopus 101 (background luminance 10 cd/m(2)) in 81 eyes of 81 ophthalmologically healthy subjects (11-12 per decade of age) aged 10-79 years. A 4-2-2 staircase strategy with three reversals was run. The test point grid consisted of 68 concentrically arranged points with test point condensation towards the VF centre, representing the approximately rotation-symmetrical 30 degrees hill of vision. Thresholds of differential luminance sensitivity (DLS) were estimated by the maximum likelihood method. A smooth mathematical model was fitted to the normative data.

RESULTS

The model fit was satisfactory (r(2) = 0.74). Covariables were: age, eccentricity, angle and subject. Total random standard deviation (SD) was 1.75 dB. The residual SD exceeded 1.75 dB in the border region, was 1.5 dB within the centre and fell below 1.25 dB in a ring around the centre. Average thresholds of DLS varied with age quadratically. It is close to constant for the 10-40-year-old age group and declines ever more steeply thereafter. The effect of age on DLS in the VF increased with eccentricity. The greatest drop was located in the peripheral superior hemifield: at 25 degrees eccentricity the superior DLS was estimated to be 5.5 dB higher in 10-year-olds than in 75-year-olds.

CONCLUSIONS

This new smooth model allows for the prediction of age-related normal threshold values for any stimulus location within the 30 degrees VF and thus for the calculation of global and local measures of defect such as mean defects or p-values for any type of stimulus.

Zum Nachweis der zentralen Empfindlichkeitsverminderung bei Optikus-Neuropathien mit der Computerperimetrie (Octopus) und mit den visuell evozierten Potentialen (VEP)

Contrast sensitivity, as far as tested with pattern-VEPs, and light-difference sensitivity, psychophysically tested with the Octopus in the visual field center, seem to reflect different visual functions, because they are disturbed to a different degree in discrete neuropathies: light-difference sensitivity may be within normal range and a careful numerical analysis is needed in order to find pathologic differences. With VEPs, on the other hand, it is easier to detect a loss of normal neural conduction.

Wie sehen Glaukomgesichtsfelder wirklich aus?

Analysis of the visual fields of 20 glaucoma patients using 229 F2 programmes consisting of 30 degrees long profiles with 1 degree resolution and double measurements of the light sensitivity threshold, revealed that there is a positive correlation between mean loss and mean short-term fluctuations; short-term fluctuations tend to be larger with increasing loss of sensitivity. However, small short-term fluctuations were also seen in areas of greatly reduced sensitivity. Analysis of the F2 programmes showed 12 different abnormal patterns. The pattern most frequently found, "increased scatter with normal sensitivity", appears to be the earliest perimetric sign of glaucoma. Progression of the glaucomatous damage produces a "gray area of increased scatter", usually accompanied by reduced sensitivity with a poorly defined lower and upper threshold.

Recovery of visual fields in brain-lesioned patients by reaction perimetry treatment

BACKGROUND

The efficacy of treatment in hemianopic patients to restore missing vision is controversial. So far, successful techniques require laborious stimulus presentation or restrict improvements to selected visual field areas. Due to the large number of brain-damaged patients suffering from visual field defects, there is a need for an efficient automated treatment of the total visual field.

METHODS

A customized treatment was developed for the reaction perimeter, permitting a time-saving adaptive-stimulus presentation under conditions of maximum attention. Twenty hemianopic patients, without visual neglect, were treated twice weekly for an average of 8.2 months starting 24.2 months after the insult. Each treatment session averaged 45 min in duration.

RESULTS

In 17 out of 20 patients a significant and stable increase of the visual field size (average 11.3 degrees +/- 8.1) was observed as well as improvement of the detection rate in the defective visual field (average 18.6% +/- 13.5). A two-factor cluster analysis demonstrated that binocular treatment was in general more effective in augmenting the visual detection rate than monocular. Four out of five patients with a visual field increase larger than 10 degrees suffered from hemorrhage, whereas all seven patients with an increase of 5 degrees or less suffered from infarction. Most patients reported that visual field restoration correlated with improvement of visual-related activities of daily living.

CONCLUSION

Rehabilitation treatment with the Lubeck Reaction Perimeter is a new and efficient method to restore part of the visual field in hemianopia. Since successful transfer of treatment effects to the occluded eye is achieved under monocular treatment conditions, it is hypothesized that the damaged visual cortex itself is the structure in which recovery takes place.

[Diagnostic capability of PULSAR, FDT y HRT-II in glaucoma suspects]

PURPOSE

To determine the diagnostic capability of PULSAR-T30W, FDT-Threshold-N30 and HRT-II in glaucoma suspects.

METHODS

Forty-seven eyes from 47 referred glaucoma suspects (GS) were examined twice with each technique. Cases with TOP-WW-MD>6dB were excluded. Results were compared with those of 70 eyes from 70 normal controls (C).

RESULTS

Mean MD value using TOP-WW in the GS group (0.96dB. sd=1.7) was not significantly different from C (0.8dB. sd=1.77) (p>0.05). Disc area in GS group (2.12 mm(2). sd=0.34) was significantly greater than in C (1.97 mm2. sd=0.45) (p<0.01). For 95.7% specificity, PULSAR-sLV showed the highest sensitivity of 30.9% in individual examinations. The highest reproducible sensitivity in the two examinations was obtained using HRT-II maximum contour elevation (23.4%) and reference height (23.4%), and was 14.9% for various indices after correcting for the influence of disc area (cup area, cup/disc area ratio, maximum contour depression and mean RNFL thickness). Reproducible sensitivity of the perimetric indices was: PULSAR-MD=8.5%, PULSAR-sLV=17%, FDT-MD=6.4%, FDT-PSD=4.3%. The association of perimetric and HRT-II indices achieved high sensitivity but low diagnostic reproducibility.

CONCLUSIONS

The most effective indices were maximum contour elevation, reference height and PULSAR-sLV, although the inclusion of the optic nerve head assessment in the selection of the GS sample may have favored the HRT-II results.

Discriminating Ability of Humphrey Matrix Perimetry in Early Glaucoma Patients

PURPOSE

To determine the discriminating ability of some parameters provided by Humphrey Matrix perimetry for early glaucoma detection.

METHODS

A prospective cross-sectional study was performed. Sixty-five primary open-angle glaucoma patients with early-stage visual field defects on standard automated perimetry (mean deviation = -1.98 +/- 1.93 dB) and 56 healthy subjects were included. All subjects performed the Humphrey Matrix perimetry with a threshold 30-2 strategy. The receiver operating characteristic (ROC) curve was constructed for each parameter and calculated the area under the ROC curve (AUC) to seek the best discriminating parameter for early glaucoma detection.

RESULTS

The AUCs of Humphrey Matrix perimetry with the mean deviation, pattern standard deviation, Glaucoma Hemifield Test, number of points that have a p < 5% in pattern deviation plot (PDP) and number of points that have a p < 1% in PDP were 0.795, 0.808, 0.689, 0.985 and 0.946, respectively.

CONCLUSION

Humphrey Matrix perimetry allowed accurate discrimination between normal and early glaucomatous eyes. The number of points that had a p < 5% in PDP was the best discriminating parameter for early glaucoma detection using Humphrey Matrix perimetry.

A comparison of global indices between the Medmont Automated Perimeter and the Humphrey Field Analyzer

BACKGROUND

Two commonly used perimeters in Australia are the Humphrey Field Analyzer II (HFA) and the Medmont Automated Perimeter (MAP). Each device describes the visual field in terms of numerical values called global indices; however, these values are not interchangeable between devices. This study was designed to directly compare the global indices of HFA and MAP visual fields.

METHODS

63 subjects who had suspected glaucoma, ocular hypertension or glaucoma, or were normal controls were recruited selectively. Each patient was tested with the MAP and HFA. Global indices were then compared between tests. These included mean deviation (MD) and pattern standard deviation (PSD) from the HFA and average defect (AD) and pattern defect (PD) from the MAP.

RESULTS

The MD and PSD results were strongly correlated with the AD and PD results, respectively. The relationship between them could be described in terms of two polynomial equations: AD = 0.94+1.31(MD)+0.02(MD)(2) and PD = 2.21(PSD)-0.05(PSD)(2)-0.006. These non-linear relationships may be the result of differences in testing method (test stimulus spectrum, number of testing locations or background luminance) or differences in the way each global index was calculated.

CONCLUSION

The AD and PD results obtained from the MAP may be substituted for the MD and PSD results from the HFA after appropriate conversion.

[Computer fusion of the mfVEP and HVF images]

INTRODUCTION

The purpose of this paper is to show a method of data fusion from two different tests: the multifocal visual evoked potentials (mfVEP) and humphrey visual field (HVF). Fusing the results may lead to a better diagnosis of various diseases associated with changes of patient's field-of-view.

MATERIAL AND METHODS

Two methods were used: mfVEP and HVF. MatLab environment was used for computer fusion of the images obtained in the mfVEP and HVF tests.

RESULT

The two methods results' fusion was achieved during computer experiments.

CONCLUSIONS

Achieved results will allow more precise and objective analysis of patient's field-of-view.

[Assessment of the macula function by static perimetry, microperimetry and rarebit perimetry in patients suffering from dry age related macular degeneration]

PURPOSE

To compare the visual field results obtained by static perimetry, microperimetry and rabbit perimetry in patients suffering from dry age related macular degeneration (AMD).

MATERIAL AND METHODS

Fifteen eyes with dry AMD (hard or soft macula drusen and RPE disorders) were enrolled into the study. Static perimetry was performed using M2 macula program included in Octopus 101 instrument. Microperimetry was performed using macula program (14-2 threshold, 10dB) within 10 degrees of the central visual field. The fovea program within 4 degrees was used while performing rarebit perimetry.

RESULTS

The mean sensitivity was significantly lower (p<0.001) during microperimetry (13.5 dB) comparing to static perimetry (26.7 dB). The mean deviation was significantly higher (p<0.001) during microperimetry (-6.32 dB) comparing to static perimetry (-3.11 dB). The fixation was unstable in 47% and eccentric in 40% while performing microperimetry. The median of the "mean hit rate" in rarebit perimetry was 90% (range 40-100%). The mean examination duration was 6.5 min. in static perimetry, 10.6 min. in microperimetry and 5,5 min. in rarebit perimetry (p<0.001). Sensitivity was 30%, 53% and 93% respectively.

CONCLUSIONS

The visual field defects obtained by microperimetry were more pronounced than those obtained by static perimetry. Microperimetry was the most sensitive procedure although the most time-consuming. Microperimetry enables the control of the fixation position and stability, that is not possible using the remaining methods. Rarebit perimetry revealed slight reduction of the integrity of neural architecture of the retina. Microperimetry and rarebit perimetry provide more information in regard to the visual function than static perimetry, thus are the valuable method in the diagnosis of dry AMD.

Relative scotomata in the "normal" eye of functionally amblyopic patients. A scanning laser ophthalmoscope (SLO) micreperimetric study

PURPOSE

To evaluate amblyopic patients with scanning laser ophthalmoscope (SLO) microperimetry to determine whether SLO assessment and data might provide useful information in our understanding of amblyopia and determine its utility in the evaluation of amblyopic patients.

METHODS

In this retrospective case series, selected for SLO testing case series, clinical data of forty-six patients with amblyopia were reviewed after completion of treatment for anisometropic or strabismic amblyopia. Ten ophthalmologically age-matched, normal patients served as controls. All patients were tested with the SLO, evaluating for the presence of macular scotomata. SLO findings were assessed within each group and between groups.

RESULTS

A macular scotoma was found in the amblyopic eye of 25 of 26 anisometropic amblyopic patients and all 20 strabismic amblyopia patients. Twenty of 26 patients with anisometropic amblyopia had a relative scotoma in the non-amblyopic "normal" eye. All 20 patients with strabismic amblyopia also had a non-amblyopic "normal" contralateral eye scotoma. None of the normal control patients had a scotoma in either eye. Several ocular and binocular clinical features were correlated to scotoma findings within and between groups.

CONCLUSION

The SLO proved useful for the assessment of some features of amblyopia. A scotoma was identified not only in the amblyopic eye of all but one amblyopic patient, as expected, but also in almost all of the fellow non- amblyopic, presumed "normal" contralateral eyes, and in spite of treatment normalization of visual acuity and stereoacuity in several cases. Thus, the ocular and binocular pathological effects of unilaterally functional amblyopia are not limited to the amblyopic eye but may also be seen, to a sub-clinical degree, by SLO microperimetry in the supposedly normal contralateral eye as well as in the apparently successfully treated previously amblyopic eye.