Perimetry In Glaucoma Patients Research Articles

Correlation of Binocular Perimetry Screening using imo, a Portable Head Mounted Perimeter with 10-2 Standard Automated Perimetry for Early Glaucoma with Central Visual Field Defects.

The screening program using imo strongly correlates with 10-2 Standard automated perimetry in detecting central visual field defects in early glaucoma, highlighting its potential as a valuable tool for efficient screening and severity quantification. To investigate the correlation between abnormalities within the central 10° of the screening program using imo, a portable head-mounted perimeter, and 10-2 standard automated perimetry in early-stage glaucoma with central visual field defects. This retrospective study included early glaucoma with (26 eyes) and without (38 eyes) central visual field defects. The correlation between the numbers of abnormal points within the central 10° of the imo screening program and those in the probability plot of 10-2, and mean total deviation and pattern deviation, were analyzed. The imo screening program demonstrated sensitivity (80%) and specificity (98.7%) in detecting abnormalities, with a 91.6% agreement rate of 10-2. The mean number of anomalies in the 10-2 plot (pattern deviation) with P<1% was 0.85, 7.75, and 9.69 (95% confidence interval: 0.18-1.51, 5.38-10.1, and 6.89-12.5, respectively) for no, one, and two anomalies in the imo screening program, respectively. The number of anomalies with P<1% was significantly higher when the imo screening program detected one anomaly versus none (P<0.01), and two versus one (P<0.05). Mean total deviation values were -1.15, -7.5, and -15.2 (95% confidence interval: -2.32 to 0.03, -11.21 to -3.78, and -19.7 to -10.6, respectively), while mean pattern deviation values were -1.57, -9.0, and -16.0 (95% confidence interval: -2.57 to -0.57, -12.5 to -5.49, and -21.4 to -10.7, respectively), for no, one, and two anomalies in the imo screening program, respectively. The imo portable head-mounted perimeter was found to correlate with 10-2 standard automated perimetry in glaucoma patients with central visual field defects and has the potential to shorten visual field testing times.

Improving the Accuracy and Speed of Visual Field Testing in Glaucoma With Structural Information and Deep Learning.

To assess the performance of a perimetric strategy using structure-function predictions from a deep learning (DL) model. Visual field test-retest data from 146 eyes (75 patients) with glaucoma with (median [5th-95th percentile]) 10 [7, 10] tests per eye were used. Structure-function predictions were generated with a previously described DL model using cicumpapillary optical coherence tomography (OCT) scans. Structurally informed prior distributions were built grouping the observed measured sensitivities for each predicted value and recalculated for each subject with a leave-one-out approach. A zippy estimation by sequential testing (ZEST) strategy was used for the simulations (1000 per eye). Ground-truth sensitivities for each eye were the medians of the test-retest values. Two variations of ZEST were compared in terms of speed (average total number of presentations [NP] per eye) and accuracy (average mean absolute error [MAE] per eye), using either a combination of normal and abnormal thresholds (ZEST) or the calculated structural distributions (S-ZEST) as prior information. Two additional versions of these strategies employing spatial correlations were tested. S-ZEST was significantly faster, with a mean average NP of 213.87 (SD = 28.18), than ZEST, with a mean average NP of 255.65 (SD = 50.27) (P < 0.001). The average MAE was smaller for S-ZEST (1.98; SD = 2.37) than ZEST (2.43; SD = 2.69) (P < 0.001). Spatial correlations further improved both strategies (P < 0.001), but the differences between ZEST and S-ZEST remained significant (P < 0.001). DL structure-function predictions can significantly improve perimetric tests. DL structure-function predictions from clinically available OCT scans can improve perimetry in glaucoma patients.

Correlation between disc damage likelihood scale and vertical cup disc ratio with Automated Humphrey Perimetry in glaucoma patients attending a tertiary care hospital, Kathmandu, Nepal

Glaucoma is the second leading ocular disease of irreversible blindness. Glaucoma is a progressive disorder and requires serial evaluation in order to monitor disease progression and optimize therapy. The objective of this study was to determine the correlation between disc damage likelihood scale (DDLS) and vertical cup disc ratio (VCDR) with the results of Humphrey field analyzer (HFA) parameters. This study was a descriptive, cross-sectional and observational study. A total of 104 eyes of 52 patients diagnosed with primary open angle glaucoma or normal tension glaucoma were examined. DDLS staging, VCDR and HFA 24-2 visual fields were obtained from the patients. The correlation of DDLS and VCDR with Mean deviation (MD), Pattern standard deviation (PSD) and Glaucoma hemi field test (GHT) of HFA was calculated by Pearson correlation coefficient (r). DDLS showed a coefficient correlation value of r = -.628, r = .391 and r = .395 (p = &lt;0.000) when correlated against HFA MD, PSD and GHT respectively. VCDR showed a coefficient correlation value of r = -.524, r = .317 and r = .221 when correlated against HFA MD, PSD and GHT respectively. DDLS has a better correlation compared to VCDR with all the parameters.

Evaluating the role of OCT in optic disc analysis in glaucoma patients

Background: thirty patients underwent full ophthalmic examination, including a review of medical history, best-corrected visual acuity, slit-lamp biomicroscopy, intraocular pressure measurement, gonioscopy, dilated fundoscopic examination, automated perimetry, and OCT at 1 month and after 6 months. Objectives: the aim of the study was to assess RNFL thickness, ONH clinically and by OCT and correlate RNFL thickness by OCT with visual fields by standard automated perimetry in glaucoma patients, highlighting the usefulness of OCT in glaucoma patients where diagnosis by standard means were not confirmatory. Patients and methods: All patients were scanned using SD-OCT (RS-3000; Nidek) after dilation with 1% tropicamide eye drop and the images were acquired by a single operator. Also, standard automated perimetry was conducted using the SITA 24-2 of the Humphrey Field Analyzer program (Carl Zeiss Meditec) with a Goldmann size III stimulus on a 31.5-apostilb background. Results: There was a statistically significant difference between patients at 1 month and after 6 months as regards OCT (RNFL), on comparison between the four quadrants at 1 month the mean of the inferior quadrant was > superior > temporal > nasal respectively. After 6 months the mean of the four quadrants as well as the total RNFL thickness decreased but only the decrease in the temporal quadrant and total RNFL thickness was statistically significant (P=0.003, P=0.044 respectively). Conclusion: An OCT would be significantly informative early in the disease course to diagnose a preperimetric glaucoma, to confirm on a visual field, and to follow up glaucoma progression.

Evaluating the role of OCT in optic disc analysis in glaucoma patients

Background: thirty patients underwent full ophthalmic examination, including a review of medical history, best-corrected visual acuity, slit-lamp biomicroscopy, intraocular pressure measurement, gonioscopy, dilated fundoscopic examination, automated perimetry, and OCT at 1 month and after 6 months. Objectives: the aim of the study was to assess RNFL thickness, ONH clinically and by OCT and correlate RNFL thickness by OCT with visual fields by standard automated perimetry in glaucoma patients, highlighting the usefulness of OCT in glaucoma patients where diagnosis by standard means were not confirmatory. Patients and methods: All patients were scanned using SD-OCT (RS-3000; Nidek) after dilation with 1% tropicamide eye drop and the images were acquired by a single operator. Also, standard automated perimetry was conducted using the SITA 24-2 of the Humphrey Field Analyzer program (Carl Zeiss Meditec) with a Goldmann size III stimulus on a 31.5-apostilb background. Results: There was a statistically significant difference between patients at 1 month and after 6 months as regards OCT (RNFL), on comparison between the four quadrants at 1 month the mean of the inferior quadrant was > superior > temporal > nasal respectively. After 6 months the mean of the four quadrants as well as the total RNFL thickness decreased but only the decrease in the temporal quadrant and total RNFL thickness was statistically significant (P=0.003, P=0.044 respectively). Conclusion: An OCT would be significantly informative early in the disease course to diagnose a preperimetric glaucoma, to confirm on a visual field, and to follow up glaucoma progression.

A comparison between the diagnostic results of short wavelength automated perimetry and standard automated perimetry in glaucoma patients

Purpose The aim of this study was to compare the diagnostic results of short wavelength automated perimetry (SWAP) and standard automated perimetry (SAP) in glaucoma patients. Patients and methods This study was held in Qena University Hospital from March 2012 to December 2012 and included 60 individuals who underwent full ophthalmological examination by means of slit-lamp biomicroscopy, gonioscopy, best-corrected visual acuity testing on Landolt's chart, fundus and optic nerve head examination using a +90 D lens, intraocular pressure (IOP) measurement by means of applanation tonometry, and finally optic nerve head photography using a Zeiss Visucam 500 fundus camera. The participants were divided into three groups: a normal age-matched control group (group A); a group with primary open-angle glaucoma POAG (group B); and a group with ocular hypertension OHT and glaucoma suspects (group C). Informed consent was obtained from all controls and patients after the nature and possible consequences of the procedure had been fully explained to them. All statistical analyses were performed by using IBM SPSS statistics. Results Thirty randomly selected eyes of 30 volunteers made up group A, 20 eyes of 20 POAG patients comprised group B, and 10 eyes of 10 ocular hypertension patients and glaucoma suspects comprised group C. The mean age of the 60 individuals included in the present study was 70.18 years (range: 60-82 years, SD: ±8.068); 29 were female and 31 were male. The prevalence of SWAP and SAP in glaucoma patients showed deficits in groups B and C, as defined by the presence of a glaucoma hemifield test 'outside normal limits'. According to this criterion, three of 10 (33.3%) group C eyes demonstrated a SWAP deficit at the second visit, whereas no (0%) eyes showed a deficit in SAP at the same time point. All 20 patients of group B manifested abnormal SWAP. The level of agreement in terms of the severity of field loss between SWAP and SAP for groups B and C, based on the pattern SD, was studied. In the present study we found that visual field loss was greater and more diffuse in SWAP than in SAP, but no patient exhibited new scotomata. Conclusion SWAP is superior to SAP in identifying patients with early glaucoma, ocular hypertension, glaucoma suspects, and patients with progressive optic disc cupping and may therefore be quite useful for determining early and progressive changes in glaucoma.

Comparative Analysis of Visual Field Plotting by Octopus Interzeag 1-2-3, Humphrey Field Analyser II and Frequency Doubling Perimetry in Glaucoma Patients in South Indian Population.

Standard achromatic perimetry tests the differential light sensitivity whereas the frequency doubling technology tests the contrast sensitivity. The aim of this study was to compare and correlate the visual field indices with three different types of perimeters namely frequency doubling perimetry (FDP), Humphrey field analyser (HFA) and Octopus Interzeag 1-2-3 (OI) for detecting glaucomatous field defects. Prospective cross-sectional observational study. Hundred eyes of 50 glaucoma patients were studied. All the patients underwent visual field examinations by Octopus Interzeag 1-2-3, Humphrey field Analyser II and Frequency Doubling perimetry (FDP). The correlations of the global indices were compared. The time taken to perform the test with the three perimeters was analysed. The visual field plotting by the perimeters were comparable and significant positive correlation was observed. The time taken to perform visual field test by Octopus Interzeag 1-2-3 was shorter than the other two methods. The visual field plotting by Octopus Interzeag 1-2-3, Humphrey field analyser and frequency doubling technology perimetry were comparable and Octopus field plotting takes lesser time than the rest two methods.

A Comparison of False-negative Responses for Full Threshold and SITA Standard Perimetry in Glaucoma Patients and Normal Observers

To compare false-negative (FN) rates for Full Threshold (FULL) and Swedish Interactive Threshold Algorithm (SITA) Standard automated perimetry in healthy control subjects and glaucoma patients. One eye of 19 glaucoma patients and 5 normal control subjects underwent 5 visual field examinations within 6 weeks on the Humphrey Field Analyzer II using the 24-2 FULL and SITA testing procedures. The order of presentation of test procedures was counterbalanced across participants. We obtained FN response procedures that presented stimuli 9 dB greater than a previously determined threshold value at specific locations in the visual field (FULL) or up to 20 dB greater than the threshold value (SITA), and evaluated whether the patient responded to these suprathreshold stimuli. We compared the percentage of FN responses for the FULL and SITA tests before (Peridata output) and after postprocessing of data. The percentage of FNs was almost twice as high for FULL testing compared with the 2 SITA analyses. The SD of FN percentages was half as large for SITA postprocessing compared with FULL and SITA Peridata procedures. Because the distributions were not normally distributed, a Kruskal-Wallis analysis of variance was performed and revealed a statistically significant difference (H=13.094, P<0.001) for FN percentages among the 3 evaluations. FULL test procedures yield about twice as many FNs as SITA procedures. This may be related to the SITA method of testing for FN in relatively normal areas as opposed to any location (even if it has low sensitivity) with FULL. Because FN responses can be due to either high variability in damaged areas or pathologic variations, these revised FN procedures provide greater assistance in properly interpreting visual field results.

Relationship between flicker FDF perimetry and standard automated perimetry in glaucoma patients

Abstract Purpose To compare the main indices of flicker FDF perimetry (FDF, Heidelberg Engineering, Germany) with standard automated perimetry (SAP) in glaucoma patients. Methods Twenty‐three open‐angle glaucoma patients were prospectively and consecutively selected. Glaucomatous patients had an intraocular pressure higher than 21 mmHg and glaucomatous optic disc appearance. All of them underwent at least one reliable perimetry with each device. SAPs were performed with a FDF perimeter (24‐2 ASTA‐Standard test) and Humphrey perimeter (Carl Zeiss (24‐2 SITA standard algorithm). The Kolmogorov Smirnov test was applied to check that the data were normally distributed. Only one eye per subject was included in the study. Spearman correlations were calculated between both devices : mean deviation (MD), pattern standard deviation (PSD), and visual field index (VFI). Results : Mean age was 65.07±8.67 years. MD of SAP was ‐6.73 ± 6.23 dB, and MD of FDF was ‐7.70 ± 5.84 dB (p=0,123); PSD of SAP was 6.07 ± 3.62, and PSD of FDF was 3.91 ± 1.89 (p = 0.953). The correlations between MDs were 0.736 (p&lt;0.001) and between PSDs were 0.320 (p&gt;0.05) Conclusion Moderate correlations were found between main visual field indices both devices. Altough no differences were found, FDF tends to present MD values lower than Humphrey.

Long-term variability in short-wavelength automated perimetry compared to standard perimetry in glaucoma patients and normal subjects

Aims:To compare long-term variability (LTV) in short-wavelength automated perimetry (SWAP) with that of standard white-on-white (W-W) perimetry, in primary open angle glaucoma (POAG) patients and normal subjects and to determine its clinical significance.Patients and Methods:The sample comprised 30 patients of stable POAG (group 1) and 20 age-matched normal controls (group2) who performed both SWAP and W-W perimetry thrice at monthly intervals. Long-term variability at each location in the visual field was calculated as the standard deviation of three threshold decibel values taken from the three visual fields performed. Mean LTV was then calculated for the entire field for each subgroup and compared.Results:Mean LTV in SWAP and W-W perimetry in glaucoma patients was 3.01 ± 0.74 dB and 2.73 ± 1.07dB respectively. In normal subjects mean LTV of SWAP and W-W perimetry was 2.69 ± 0.91 db and 1.97 ± 1.34 dB respectively. Intra group analysis revealed that mean LTV of SWAP was greater compared to W-W perimetry in normal subjects and glaucoma patients. In the latter, the difference did not reach statistical significance. Inter group analysis showed that mean LTV in both SWAP and W-W perimetry was greater in glaucoma patients than in normal subjects. Factors other than POAG that could influence LTV, including progression of cataract and change in pupil size due to use of pilocarpine were excluded. Mean examination time for SWAP per sitting was 7.65% longer than that for W-W perimetry.Conclusions:Higher mean LTV of SWAP as compared to W-W perimetry needs to be taken into consideration when evaluating serial visual fields for change. Use of rapid threshold algorithms e.g. SITA (Swedish interactive test algorithm) SWAP should be encouraged as these will reduce the patient fatigue and increase the reliability of the test.

A Comparison of Catch Trial Methods Used in Standard Automated Perimetry in Glaucoma Patients

To compare the false-positive (FP) response rates between 2 methods used by the Humphrey Field Analyzer in glaucoma patients. One eye of one hundred and twenty glaucoma patients was tested twice within 2 months with 24-2 SITA Standard and 24-2 full threshold (FT) perimetric test procedures. FP rates were obtained with the response time window (RTW) method used by SITA and the blank presentation (BP) method of the size V FT procedure. False-negative (FN) catch trial rates were also examined. A repeated measure, 2 x 2 analysis of variance was used to examine error rates, and FP rates for visits 1 and 2 were regressed to investigate its relationship. For FP rates on the first 2 visits, glaucoma patients had no significant differences comparing RTW (SITA) with BP (FT) (1.99% vs. 1.88%) and higher mean FN rates (4.11% vs. 1.69%, P=0.001); the FP rates at visit 2 were similar (1.69% vs. 2.08%) and FN rates were lower for both methods at visit 2. However, when comparing patients with FP responses that occurred with both RTW and BP methods, RTW rates were lower (3.58% vs. 7.72%, P=0.007). The RTW method seems to underestimate FP response rates.

Realationship optical coherence tomography and short‐wavelength automated perimetry in glaucoma patients

Abstract Purpose To correlate the main indices of short‐wavelength automated perimetry (SWAP) with the peripapillary retinal nerve fiber layer (RNFL) thickness measured with optical coherence tomography (OCT) in glaucoma patients. Methods 66 eyes of 66 glaucoma patients were prospective and consecutively selected. All of them had intraocular pressure &gt;21 mmHg, and reproducible glaucomatous visual field loss in standard automated perimetry. SWAP test were performed with a Humphrey perimeter and the 24‐2 full threshold algorithm. Pearson correlations were calculated between SWAP indices (mean deviation and pattern standard deviation) and OCT parameters. Results Mild significant (p&lt;0.05) correlations were observed between SWAP indices and some OCT parameters. The strongest correlations were found between the RNFL thickness in the vertical axis (superior and inferior pole thickness) and mean deviation of SWAP. Pattern standard deviation did not correlate with any OCT parameter. Average thickness and superior quadrant thickness had the strongest correlations with mean deviation of SWAP (both 0.36). Conclusion RNFL thickness measured with OCT showed mild correlations with SWAP indices in glaucoma subjects.

Detection of glaucomatous visual field defect by nonconventional perimetry

PurposeTo 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. DesignCross-sectional study. MethodsEighty-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. ResultsFifty-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. ConclusionsOur data suggest that FDT and HRP are useful for detection of early glaucomatous visual field damage.

Learning effect and measurement variability in frequency-doubling technology perimetry in chronic open-angle glaucoma.

To prospectively study the learning effects and measurement variability in frequency-doubling technology perimetry in glaucoma patients who were well practiced in testing with an automated static perimeter. Patients with clinically stable chronic open-angle glaucoma (n = 44) who had undergone repeated perimetric testing using a 30-2 full-threshold program with a Humphrey perimeter with reliable results were enrolled in the study. The authors tested each patient using frequency-doubling technology perimetry. After initial examination with the C-20-1 screening program, the N-30 full-threshold program was performed three times at 1- to 3-month intervals. Perimetric results of the N-30 program improved with repeated testing in both eyes between the first and second visits. The average of mean deviation (MD) of the N-30 program significantly improved by 0.6 dB ( < 0.001) in the right eye and 0.8 dB ( < 0.002) in the left eye between the first and second sessions. The sensitivity in 4 of 19 test points (right eye) and 5 of 19 points (left eye) improved significantly at the second sessions, but not the third session. There were no significant differences in the FDT results between the second and third sessions in both eyes. The standard deviation of the mean MD value for the three sessions ranged from 3.8 to 4.0 dB in both eyes. Baseline measurements for perimetric follow-up with the N-30 full-threshold program in patients with glaucoma should be repeated at least twice after testing with the C-20-1 screening program.

A new scoring system for comparing the results of high‐pass resolution perimetry and differential light sensitivity perimetry in glaucoma patients

Using a new standard, we compared the visual field defects detected by high-pass resolution perimetry (HRP) and differential light sensitivity (DLS) perimetry in 61 eyes of 61 open-angle glaucoma patients. Abnormal test points were determined using probability plot analysis of HRP and total deviation probability maps of the Humphrey Field Analyzer. To evaluate the agreement between the two tests, we developed a new scoring system. Thirty-three eyes, 23 eyes, and 5 eyes had good, fair, and poor agreement, respectively. In relation to Aulhorn's stage classification, the more advanced the glaucomatous stage, the more increased the percentages of good agreement. These results suggest that the distribution and severity of visual field defects demonstrated by HRP agree closely with those found using DLS perimetry in glaucomatous eyes, especially those with advanced visual field changes.

Effects of Pupillary Dilation on Automated Perimetry in Glaucoma Patients Receiving Pilocarpine

The authors studied 18 glaucoma patients receiving pilocarpine 2% therapy with automated static threshold perimetry using the Humphrey Field Analyzer 30-2 and STATPAC programs before and after instillation of 10% phenylephrine. The mean defect improved by an average of 3.14 decibels (dB) (standard deviation, 1.89 dB0 after administration of phenylephrine (P less than 0.001). The pattern standard deviation and the corrected pattern standard deviation also improved with dilation by 1.42 dB (P less than 0.01) and 1.73 dB (P less than 0.05), respectively, after dilation with phenylephrine. Comparisons of the unweighted means of threshold values in three zones of increasing eccentricity showed that the outer zone of the visual field had the greatest improvement after dilation. These findings indicate that pupillary dilation in glaucoma patients receiving pilocarpine therapy produces a nonuniform increase in threshold sensitivities and support the importance of consistent pupillary diameters on serial automated visual field examinations.

Significance of the peripheral visual field for diagnosis of glaucoma

Investigated was the significance of semiquantitative tests of the peripheral visual field in glaucoma. For that purpose 793 visual fields of 793 glaucoma patients or glaucoma suspects and 338 visual fields of 338 normal controls (normal central 26 degrees--area) were analysed. Perimetry was performed with an Octopus 201 with the help of program G1, which tests 14 peripheral test locations. In the majority of the 455 glaucoma patients (pathological findings in the central visual field) the periphery was also disturbed. Much to our surprise however, the 338 glaucoma suspects (having normal central visual fields) showed the same frequency of peripheral visual field disturbance as the normals. This holds true for the total peripheral visual field, as well as for the individual test locations. Therefore it makes sense to limit perimetry in glaucoma patients to the central area, provided that the central area is quantitatively measured with an adequate testgrid.