Standard Automated Perimetry Results Research Articles

Clinical evaluation of the eye-to-visual-pathway integrity of glaucomatous neurodegeneration using 1.5T MR imaging: The integrity of glaucomatous neurodegeneration

Aim: Accumulating data imply that glaucoma may represent a neurodegenerative disorder affecting the entire visual system. We evaluated retrobulbar glaucomatous damage with favorable techniques for 1.5T diffusion-tensor magnetic resonance imaging and we compared those techniques with clinical data in a large case series. Material and methods: This Cross-sectional study included 130 eyes of 65 patients with primary open-angle glaucoma. Patients with no known ocular or systemic concomitant disorders, neurological diseases, previous glaucoma surgeries, or antioxidant usage were selected. A decrease in thickness and deterioration in the optic nerve diffusion of severely glaucomatous eyes of patients with asymmetrical involvement was observed in optic nerve tractography. Optical coherence tomography and visual field results of the subjects were recorded. Glaucoma analysis with optical coherence tomography and standard automated perimetry results of the subjects were recorded. Diffusion-tensor magnetic resonance imaging analysis of optic nerves and radiations were performed, computing fractional anisotropy, apparent diffusion coefficient, axial diffusivity, and radial diffusivity. Correlation between the diffusion-tensor magnetic resonance imaging and clinical eye parameters of glaucomatous neurodegeneration were statistically evaluated. Results: The correlations between diffusion parameters and age were highly significant. Statistically significant correlations were found between ganglion cell complex and apparent diffusion coefficient, axial and radial diffusivities of optic nerves. Conclusion: Eye-brain connection in glaucoma can be evaluated with routine clinical instruments. Our study also revealed a limited correlation of retrobulbar glaucomatous neurodegeneration with ophthalmic damage. A better understanding of retrobulbar damage will enable us to develop more efficient strategies and a more accurate understanding of glaucoma.

False Positive Responses in Standard Automated Perimetry

To analyze the relationship between rates of false positive (FP) responses and standard automated perimetry results. Prospective multicenter cross-sectional study. One hundred twenty-six patients with manifest or suspect glaucoma were tested with Swedish Interactive Thresholding Algorithm (SITA) Standard, SITA Fast, and SITA Faster at each of 2 visits. We calculated intervisit differences in mean deviation (MD), visual field index (VFI), and number of statistically significant test points as a function of FP rates and also as a function of general height (GH). Increasing FP values were associated with higher MD values for all 3 algorithms, but the effects were small, 0.3 dB to 0.6 dB, for an increase of 10 percentage points of FP rate, and for VFI even smaller (0.6%-1.4%). Only small parts of intervisit differences were explained by FP (r2 values 0.00-0.11). The effects of FP were larger in severe glaucoma, with MD increases of 1.1 dB to 2.0 dB per 10 percentage points of FP, and r2values ranging from 0.04 to 0.33. The numbers of significantly depressed total deviation points were affected only slightly, and pattern deviation probability maps were generally unaffected. GH was much more strongly related to perimetric outcomes than FP. Across 3 different standard automated perimetry thresholding algorithms, FP rates showed only weak associations with visual field test results,except in severe glaucoma. Current recommendations regarding acceptable FP ranges may require revision. GH or other analyses may be better suited than FP rates for identifying unreliable results in patients who frequently press the response button without having perceived stimuli.

The Impacts of Face Mask Use on Standard Automated Perimetry Results in Glaucoma Patients.

The coronavirus disease 2019 (COVID-19) spread rapidly worldwide, causing a severe outbreak. Because the disease is easily transmitted, face masks are a vital tool to slow the spread. The aim of this study is to investigate the impacts of face mask use on standard automated perimetry (SAP) results in glaucoma patients. All follow-up glaucoma patients who underwent SAP between May and October 2020 were enrolled in this study. In patients with low test reliability and/or visual field changes, SAP was repeated after repositioning and taping patients' face masks. A total of 127 patients (59 female and 68 male) with a mean age of 59.8±10.3 years were included in the study. While 101 patients (79.5%) wore surgical face masks, 26 patients (20.5%) wore cloth face masks. Low SAP reliability appeared in 23 patients (18.1%), and inferior visual field defects were present in 3 patients (2.4%). The main effects of poorly fitting face masks on SAP reliability were increased fixation losses and false-positive errors (for both, P=0.001). Low SAP reliability was significantly higher in patients wearing cloth face masks than in those wearing surgical face masks (47.8% vs. 9.9%; P=0.0001). The face mask-related fogging of eyeglasses before SAP is a strong predictor of fogging of the trial lenses-related low SAP reliability (odds ratio: 27, 95% confidence interval: 5.48-132.92, P=0.0001). In all repeated SAPs, the patients' reliability parameters improved, and inferior visual field artifacts disappeared. Unsuitable face masks can cause either visual field artifacts, which may be interpreted as glaucoma progression or low test reliability. Taping the face masks' upper edges is an effective technique to prevent visual field artifacts and obtain good test reliability.

Role of visual field reliability indices in ruling out glaucoma.

Standard automated perimetry is the current criterion standard for assessment of visual field (VF) loss in glaucoma. The 3 commonly used reliability indices to judge the quality of standard automated perimetry results are fixation losses (FLs) and false-positive (FP) and false-negative (FN) response rates. However, the influence of reliability indices, when within the manufacturer-recommended limits, on VF classification has been sparsely studied. To evaluate the role of VF reliability indices in ruling out glaucoma. A cross-sectional study of 291 eyes of 291 participants referred to a tertiary eye care facility by general ophthalmologists. The participants were suspected to have glaucoma based on optic disc appearance, but the eyes were judged to be normal with physiological cupping by glaucoma experts on masked evaluation of optic disc photographs. All participants underwent VF testing with the Swedish interactive threshold algorithm standard 24-2 program. Logistic regression models were used to evaluate the associations between reliability indices and FP classifications on VF testing (glaucoma hemifield test as outside normal limits and pattern standard deviation with P < .05). Median FL, FP, and FN response rates were 7%, 1%, and 2%, respectively. Among the 241 participants with reliable VF results (FL <20% and FP response rate <15%), the VF classification was normal in 188 (78.0%) and glaucoma (FP) in 53 (22.0%). Probability of FP VF classification was associated with FN response rates (odds ratio [OR], 1.36; 95% CI, 1.25-1.48, P < .001) but did not appear to be associated with FLs (OR, 0.96; 95% CI, 0.90-1.03, P = .30) or FP response rates (OR, 0.96; 95% CI, 0.83-1.12, P = .64). Predicted probability of FP VF classification was 9% (95% CI, 6%-14%), 40% (32%-49%), and 82% (68%-91%) at FN response rates of 0%, 8%, and 16%, respectively. This study suggests that FN response rates have an effect on the ability of automated VF assessments to rule out glaucoma. Since FN response rates are ignored by the manufacturer while flagging a test as unreliable, clinicians and researchers may benefit by realizing that FN response rates can lead to FP VF classification, even when their frequencies are small.

Optic nerve head changes in early glaucoma: a comparison between stereophotography and Heidelberg retina tomography

To evaluate and compare the diagnostic accuracy of the Heidelberg retina tomograph (HRT) version 3 with that of glaucoma specialists using stereophotography in discriminating between normal eyes and patients with early glaucomatous visual field loss. A total of 105 eyes of 105 individuals were prospectively and consecutively recruited. The sample comprised 51 normal and 54 early glaucomatous eyes, as defined by intraocular pressure and standard automated perimetry results, regardless of optic disc appearance. Receiver operating characteristic (ROC) curves were plotted for the HRT3 parameters and a linear discriminant function (LDF) developed in our hospital. Best sensitivity-specificity pairs were compared between the HRT3 parameters, with the highest areas under the ROC curve (AUCs) and evaluation of optic disc stereophotographs. Agreement between methods for measuring vertical cup-to-disc ratio was evaluated with the Bland-Altman plot. The average visual field mean deviation was -2.90 dB. The HRT3 parameters with the largest AUCs were our LDF (0.900), rim volume (0.883), and vertical cup/disk ratio (0.880), with no significant differences between these parameters. Sensitivity-specificity pairs were 79.6-100% (clinical evaluation), 83.3-86.3% (our LDF), 64.8-96.1% (final glaucoma probability score), and 68.5-90.2% (global Moorfields regression analysis). The diagnostic accuracy for differentiating normal eyes from those with early visual field defects was similar between clinical evaluation of the optic disc and evaluation with the HRT3. The use of our LDF increased the sensitivity-specificity balance with respect to the HRT-provided parameters. The diagnostic accuracy of the HRT classifications was comparable to that of an experienced glaucoma specialist.

Retinal Nerve Fiber Layer Evaluation in Open-Angle Glaucoma

Purpose: To determine the optimum criteria for optical coherence tomography (OCT) to discriminate best between healthy and glaucomatous eyes. Design: A prospective cross-sectional study. Methods: In total, 164 eyes selected from clinical practice were included in this study. These were classified into 98 healthy and 66 glaucomatous eyes, depending on the intraocular pressure, appearance of the optic disc and standard automated perimetry results. Only 1 eye per subject was randomly included. The retinal nerve fiber layer (RNFL) was evaluated by means of OCT (Stratus OCT 3000). The sensitivity and specificity values of different diagnostic criteria (4 abnormal quadrants and 1–5 abnormal clock-hours) were calculated with different probability levels (p < 0.05 and p < 0.01). Results: The criterion with the best sensitivity-specificity balance was the presence of ≥2 hour positions with an RNFL thickness outside of the 95% confidence interval (CI; sensitivity = 77.2%, specificity = 91.9%). For the 99% CI, the best criterion was the presence of at least 1 abnormal hour position (sensitivity = 71.2%, specificity = 91%). Regarding retinal quadrants, the presence of at least 1 quadrant with RNFL thickness outside of the CI was the criterion that best discriminated the existence of glaucomatous damage. Conclusions: The definition of diagnostic criteria based on OCT structural parameters may improve its diagnostic ability. The highest diagnostic ability was provided by the presence of at least 2 hour positions or RNFL average thickness outside the 95% CI.

Ability of Stratus OCT to Identify Localized Retinal Nerve Fiber Layer Defects in Patients with Normal Standard Automated Perimetry Results

To evaluate the ability of Stratus optical coherence tomography (OCT; Carl Zeiss Meditec, Dublin, CA) with its internal normative database to discriminate between healthy eyes and eyes with a localized retinal nerve fiber layer (RNFL) defect not accompanied by a perimetric defect according to standard automated perimetry (SAP) (i.e., a preperimetric localized RNFL defect). Data were retrospectively reviewed from 49 eyes of 49 subjects with preperimetric localized RNFL defects, and 49 healthy control eyes of 49 age-matched subjects, with classification into each group based primarily on red-free fundus photography The sensitivity and specificity of various OCT RNFL thickness parameters for identifying subjects with preperimetric localized RNFL defects was determined. In addition, the topographic relationship between the OCT-measured RNFL thickness and the localized RNFL defect location according to red-free fundus photography (i.e., the red-free RNFL defect) was examined. results. The sensitivity of the Stratus OCT RNFL thickness parameters ranged from 2.0% to 40.8%. The highest sensitivity was yielded using a criterion of > or =1 clock hour that were abnormal at the 5% level, which had a specificity of 85.7%. The OCT-measured RNFL thickness showed excellent topographic agreement with the red-free RNFL defect location. Although the sensitivity of current Stratus OCT RNFL thickness parameters is low for preperimetric localized RNFL defects, it appears that OCT has the potential to recognize such defects. Further study is needed to develop new analytical methods that will increase OCT sensitivity for identifying preperimetric localized RNFL damage.

Combining Structural and Functional Testing for Detection of Glaucoma

To assess whether the combined use of both structural and functional tests improves discrimination between healthy and glaucomatous eyes over either type of testing alone. Observational cross-sectional study. One hundred twenty-three eyes of 123 participants enrolled in the Diagnostic Innovations in Glaucoma Study. Because both structural and functional tests were evaluated, 2 definitions of glaucoma were used: glaucomatous visual field (VF) damage based on repeatable abnormal standard automated perimetry results (n = 43) and glaucomatous optic disc (glaucomatous optic neuropathy [GON]) based on masked assessment of optic disc stereophotographs (n = 65). Participants had scanning laser polarimetry, optical coherence tomography (OCT), and confocal scanning laser ophthalmoscopy imaging in addition to frequency-doubling technology (FDT) perimetry and short-wavelength automated perimetry (SWAP) testing completed within a 6-month interval. For each glaucoma definition, sensitivities and specificities were calculated for the best structural parameters, FDT perimetry pattern standard deviation (PSD), and SWAP PSD/glaucoma hemifield test, and then for each possible pairwise combination of one structural and one functional parameter. The best structural parameters for discriminating between glaucoma and control eyes were nerve fiber indicator for scanning laser polarimetry, inferior average retinal nerve fiber layer thickness for OCT, and Moorfields regression classification for confocal scanning laser ophthalmoscopy. Sensitivities and specificities for detecting glaucomatous VF damage for scanning laser polarimetry, OCT, confocal scanning laser ophthalmoscopy, FDT perimetry, and SWAP were 41.9% and 98.3%, 58.1% and 98.3%, 58.1% and 84.5%, 44.2% and 98.3%, and 65.1% and 86.2%, respectively. Adding FDT perimetry to each of the best structural parameters led to a significant (P<0.05) increase in sensitivity without a significant change in specificity compared with structural parameters alone. Adding SWAP to each of the best structural parameters led to a significant increase in sensitivity and also a significant decrease in specificity compared with each structural parameter alone. A combination of parameters from structural tests and functional tests can improve the sensitivity of glaucoma detection. The sensitivity and specificity desired for a particular clinical application will determine the selection of the particular diagnostic tests.

Short-Wavelength Automated Perimetry in Neuro-Ophthalmologic Disorders

Objective: To evaluate the efficacy of short-wavelength automated perimetry (SWAP) in the assessment of patients with neuro-ophthalmologic disorders, especially optic neuropathies. Methods: A modified Humphrey field analyzer was used to perform standard automated perimetry and SWAP, a technique that isolates the activity of short-wavelength-sensitive (blue) mechanisms. Forty patients (80 eyes) were evaluated by SWAP and standard automated perimetry. Thirteen patients (26 eyes) had recovered from optic neuritis and/or multiple sclerosis, 15 (30 eyes) were in various stages of treatment for pseudotumor cerebri, and 12 (24 eyes) had other miscellaneous neuro-ophthalmologic conditions. Six additional patients (12 eyes) with neuro-ophthalmologic conditions were tested twice on different days during a 2-week period, with the order of SWAP and standard perimetric testing being reversed on the second day. Results: Of the 80 eyes tested, 38 (48%) had SWAP visual fields that were worse than standard automated perimetry results; 29 (36%) showed no difference between standard and SWAP visual fields; and 13 (16%) had standard automated perimetry results that were worse than SWAP visual fields. Of the 26 eyes in patients with optic neuritis and/or multiple sclerosis, 15 (58%) had SWAP results that were worse than standard visual fields. Ten (33%) of the 30 eyes with pseudotumor cerebri had SWAP results worse than standard automated perimetry results, and 13 (54%) of 24 eyes with miscellaneous neuro-ophthalmologic conditions had SWAP results worse than standard automated perimetry results. For the 12 eyes undergoing repeated testing, SWAP visual fields were worse when they were performed last, perhaps indicating that some fatigue effect was present. This was observed for standard visual fields as well, but to a smaller extent. Conclusions: Preliminary findings suggest that SWAP may be useful in detecting certain neuro-ophthalmologic deficits more readily than standard automated visual field testing, especially for optic neuritis and multiple sclerosis. Further evaluations will be necessary to define the effects of fatigue for SWAP visual fields in neuro-ophthalmologic disorders.

Short-wavelength automated perimetry in neuro-ophthalmologic disorders.

To evaluate the efficacy of short-wavelength automated perimetry (SWAP) in the assessment of patients with neuro-ophthalmologic disorders, especially optic neuropathies. A modified Humphrey field analyzer was used to perform standard automated perimetry and SWAP, a technique that isolates the activity of short-wavelength-sensitive ("blue") mechanisms. Forty patients (80 eyes) were evaluated by SWAP and standard automated perimetry. Thirteen patients (26 eyes) had recovered from optic neuritis and/or multiple sclerosis, 15 (30 eyes) were in various stages of treatment for pseudotumor cerebri, and 12 (24 eyes) had other miscellaneous neuro-ophthalmologic conditions. Six additional patients (12 eyes) with neuro-ophthalmologic conditions were tested twice on different days during a 2-week period, with the order of SWAP and standard perimetric testing being reversed on the second day. Of the 80 eyes tested, 38 (48%) had SWAP visual fields that were worse than standard automated perimetry results; 29 (36%) showed no difference between standard and SWAP visual fields; and 13 (16%) had standard automated perimetry results that were worse than SWAP visual fields. Of the 26 eyes in patients with optic neuritis and/or multiple sclerosis, 15 (58%) had SWAP results that were worse than standard visual fields. Ten (33%) of the 30 eyes with pseudotumor cerebri had SWAP results worse than standard automated perimetry results, and 13 (54%) of 24 eyes with miscellaneous neuro-ophthalmologic conditions had SWAP results worse than standard automated perimetry results. For the 12 eyes undergoing repeated testing, SWAP visual fields were worse when they were performed last, perhaps indicating that some fatigue effect was present. This was observed for standard visual fields as well, but to a smaller extent. Preliminary findings suggest that SWAP may be useful in detecting certain neuro-ophthalmologic deficits more readily than standard automated visual field testing, especially for optic neuritis and multiple sclerosis. Further evaluations will be necessary to define the effects of fatigue for SWAP visual fields in neuro-ophthalmologic disorders.