The Effect of Testing Reliability on Visual Field Sensitivity in Normal Eyes

Repeatability of Online Circular Contrast Perimetry Compared to Standard Automated Perimetry

PRCIS

Online circular contrast perimetry provides visual field assessment on any computer or tablet with no extra hardware. It has good test repeatability and reliability that is comparable with standard automated perimetry. It holds promise for use in disease screening and surveillance to expand the provision of glaucoma care.

PURPOSE

To evaluate the repeatability of online circular contrast perimetry (OCCP) compared to standard automated perimetry (SAP) in normal participants and patients with stable glaucoma over 18 weeks.

METHODS

Thirty-six participants (13 normal controls and 23 patients with open angle glaucoma) were recruited. OCCP and SAP perimetry tests were performed twice at baseline, then at 6, 12, and 18 weeks. Global perimetric indices were compared between perimetry types and analyzed for short-term and intermediate-term repeatability.

RESULTS

There were no statistically significant changes over time for both OCCP and SAP across all groups for mean deviation (MD), pattern standard deviation, and visual index/visual field index ( P >0.05). Test-retest intraclass correlation coefficients (ICCs) for OCCP MD were excellent at baseline (0.98, 95% CI: 0.89-0.99) and good at 18 weeks (0.88, 95% CI: 0.51-0.98). SAP test-retest ICCs were excellent at baseline (0.94, 95% CI: 0.70-0.99) and 18 weeks (0.97, 95% CI: 0.84-0.99). Inter-test ICCs were good, ranging from 0.84 to 0.87. OCCP testing time was shorter than SAP (5:29 ± 1:24 vs. 6:00 ± 1:05, P <0.001). OCCP had similar false-positive (3.84 ± 3.32 vs. 3.66 ± 4.53, P =0.48) but lower false-negative (0.73 ± 1.52 vs. 4.48 ± 5.00, P <0.001) and fixation loss responses (0.91 ± 1.32 vs. 2.02 ± 2.17, P <0.001).

CONCLUSIONS

OCCP allows visual field assessment on any computer screen with no additional hardware. It demonstrated good repeatability and reliability with similar performance indices to SAP in both the short term and intermediate term. OCCP has the potential to be utilized as a glaucoma screening and surveillance tool for in-clinic and at-home testing, expanding the provision of care.

Development and evaluation of Order of Magnitude (OM): a virtual reality-based visual field analyzer for glaucoma detection

PURPOSE

This study introduces the Order of Magnitude (OM), a cost-effective, indigenous, virtual reality-based visual field analyzer designed for detecting glaucomatous visual field loss.

METHODS

The OM test employs a two-step supra-thresholding algorithm utilizing stimuli of 0.43°diameter (equivalent to Goldmann size III) at low and high thresholds. A comparative analysis was conducted against the Humphrey visual field (HVF) test, considered the gold standard in clinical practice. Participants, including those with glaucoma and normal individuals, underwent comprehensive eye examinations alongside the OM and HVF tests between April and October 2019. Diagnostic sensitivity and specificity of the OM test were assessed against clinical diagnoses made by specialists.

RESULTS

We studied 157 eyes (74 glaucomatous, 83 control) of 152 participants. Results demonstrated a high level of reliability for both OM and HVF tests, with no significant difference observed (P = 0.19, Chi-square test). The sensitivity and specificity of the OM test were found to be 93% (95% CI 86-100%) and 83% (95% CI 72.4-93%), respectively, while the HVF test showed sensitivity and specificity of 98% (95% CI 93.9-100%) and 83% (95% CI 73.9-92.8%), respectively.

CONCLUSION

These findings suggest that the OM test is non-inferior to the reference standard HVF test in identifying glaucomatous visual field loss.

The Impact of Peripheral Vision on Manual Reaction Time Using Fitlight Technology for Handball, Basketball and Volleyball Players

The purpose of the research was to identify the impact of peripheral (unilateral and bilateral) vision on manual reaction time to visual stimuli in handball, basketball and volleyball players by implementing a 6-week experimental program of specific exercises and some adapted tests using Fitlight technology. The research included 412 players (212 male-51.5%; 200 female-48.5%) from three team sports: basketball-146 (35.4%), handball-140 (40%) and volleyball-126 (30.6%). The experimental program carried out over 6 weeks was identical for all handball, basketball and volleyball players participating in the study; two training sessions per week were performed, with each session lasting 30 min; 15 exercises were used for the improvement of manual reaction time to visual stimuli involving peripheral vision. Through the Analysis of Variance (ANOVA), we identified statistically significant differences between the arithmetic means of the samples of handball, basketball and volleyball players, as well as according to general samples also of gender (male and female), p = 0.000. Male and female handball samples achieved the greatest progress in manual reaction time to visual stimuli involving peripheral vision for the Reaction time test with a unilateral right visual stimulus (30 s) and the Reaction time test with a unilateral left visual stimulus (30 s), while general sample also of male and female basketball samples, for the Reaction time test with bilateral visual stimuli (30 s) and the Reaction time test with six Fitlights (1 min); male and female volleyball samples recorded the lowest progress in all tests compared to handball and basketball groups. According to our results, female samples made greater progress in reaction time than male groups for all four tests of the present study. The implemented experimental program led to an improvement in manual reaction time to visual stimuli due to the use of Fitlight technology and the involvement of peripheral vision for all research samples.

Retinal Vessel Pulsatile Characteristics Associated With Vascular Stiffness Can Predict the Rate of Functional Progression in Glaucoma Suspects

Purpose

Tissue stiffening and alterations in retinal blood flow have both been suggested as causative mechanisms of glaucomatous damage. We tested the hypothesis that retinal blood vessels also stiffen, using laser speckle flowgraphy (LSFG) to characterize vascular resistance.

Methods

In the longitudinal Portland Progression Project, 231 eyes of 124 subjects received LSFG scans of the optic nerve head (ONH) and automated perimetry every 6 months for six visits. Eyes were classified as either "glaucoma suspect" or "glaucoma" eyes based on the presence of functional loss on the first visit. Vascular resistance was quantified using the mean values of several instrument-defined parameterizations of the pulsatile waveform measured by LSFG, either in major vessels within the ONH (serving the retina) or in capillaries within ONH tissue, and age-adjusted using a separate group of 127 healthy eyes of 63 individuals. Parameters were compared against the severity and rate of change of functional loss using mean deviation (MD) over the six visits, within the two groups.

Results

Among 118 "glaucoma suspect" eyes (average MD, -0.4 dB; rate, -0.45 dB/y), higher vascular resistance was related to faster functional loss, but not current severity of loss. Parameters measured in major vessels were stronger predictors of rate than parameters measured in tissue. Among 113 "glaucoma" eyes (average MD, -4.3 dB; rate, -0.53 dB/y), higher vascular resistance was related to more severe current loss but not rate of loss.

Conclusions

Higher retinal vascular resistance and, by likely implication, stiffer retinal vessels were associated with more rapid functional loss in eyes without significant existing loss at baseline.

Longitudinal Signal-to-Noise Ratio of Perimetry at Different Severities of Glaucoma

Purpose

Automated perimetry is relied on for functional assessment of patients with glaucoma, but questions remain about its effective dynamic range and its utility for quantifying rates of progression at different stages of the disease. This study aims to identify the bounds within which estimates of rate are most reliable.

Methods

Pointwise longitudinal signal-to-noise ratios (LSNR), defined as the rate of change divided by the standard error of the trend line, were calculated for 542 eyes of 273 patients with glaucoma/suspects. The relations between the mean sensitivity within each series and lower percentiles of the distribution of LSNRs (representing progressing series) were analyzed by quantile regression, with 95% confidence intervals derived by bootstrapping.

Results

The 5th and 10th percentiles of LSNRs reached a minimum at sensitivities 17 to 21 dB. Below this, estimates of rate became more variable, making LSNRs of progressing series less negative. A significant step change in these percentiles also occurred at approximately 31 dB, above which LSNRs of progressing locations became less negative.

Conclusions

The lower bound of maximum utility for perimetry was ∼17 to 21dB, coinciding with previous results suggesting that below this point, retinal ganglion cell responses saturate and noise overwhelms remaining signal. The upper bound was ∼30 to 31 dB, coinciding with previous results suggesting that above this point, the size III stimulus used is larger than Ricco's area of complete spatial summation.

Translational Relevance

These results quantify the impact of these two factors on the ability to monitor progression and provide quantifiable targets for attempts to improve perimetry.

Online Circular Contrast Perimetry: A Comparison to Standard Automated Perimetry

PURPOSE

The aim was to validate and compare the diagnostic accuracy of a novel 24-degree, 52-loci online circular contrast perimetry (OCCP) application to standard automated perimetry (SAP).

DESIGN

Prospective cohort study.

METHODS

Two hundred and twenty participants (125 normal controls, 95 open angle glaucoma patients) were included. Agreement, correlation, sensitivity, specificity, and area under receiver operating curves (AUC) were compared for parameters of OCCP, SAP, and optical coherence tomography (OCT) for the retinal nerve fiber layer and macular ganglion cell complex inner plexiform layer.

RESULTS

Pointwise sensitivity for OCCP was greater than SAP by 1.02 log units (95% CI: 0.95-1.08); 95% limits of agreement 0.860 to 1.17. Correlation and agreement for global indices and regional zones between OCCP and SAP were strong. OCCP mean deviation (MD) AUC was 0.885±0.08, similar to other instruments' parameters with the highest AUC: SAP MD (0.851±0.08), OCT retinal nerve fiber layer inferior thickness (0.908±0.07), OCT ganglion cell complex inner plexiform layer inferior thickness (0.849±0.08), P>0.05. At best cutoff, OCCP MD sensitivity/specificity were comparable to SAP MD (90/74 vs 94/65%).

CONCLUSIONS

OCCP demonstrates similar perimetric sensitivities to SAP and similar AUC to SAP and OCT in distinguishing glaucoma patients from controls. OCCP holds promise as a glaucoma surveillance and screening tool, with the potential to be utilized for in-clinic and at-home perimetry and expand community testing.

Longitudinal evaluation of trifocal and extended depth of focus lenses implantation using standard automated perimetry parameters

PURPOSE

To evaluate reliability and global indices parameters from standard automated perimetry (SAP) in normal eyes undergoing phacoemulsification cataract surgery with implantation of trifocal or extended depth of focus intraocular lens (IOL).

METHODS

Prospective study to evaluate the effect of trifocal IOL AcrySof IQ PanOptix® and extended depth of focus intraocular lens (EDOF) Tecnis Symfony® IOL implantation on visual field parameters. Patients underwent SAP pre- and postoperatively. Reliability indices (false negative rate-FN, false positive rate-FP), global indices (foveal sensitivity threshold, visual field index-VFI, standard pattern deviation-PSD, mean deviation MD) and test duration were analyzed.

RESULTS

A total of 23 eyes from 13 patients were in the trifocal IOL group and a total of 22 eyes from 14 patients were in the EDOF group. The following results were obtained by analyzing pre- and postoperative SAP of EDOF IOL: the rate of change of FN was 1.95/1.41% (p = 0.61); FP 1.64/1.27 (p = 0.60); MD - 1.60/- 1.08 dB (p = 0.15); foveal sensitivity was 34.5/33.9 dB (p = 0.41); VFI 98.5/98.4% (p > 0.99); PSD 1.85/1.86 (p = 0.07); and for test duration 305.81/298.36 s (p = 0.35); all respectively. Analysis of pre- and postoperative parameters of trifocal IOL were the rates of change of FN 1.22/1.83% (p = 0.29); FP 1.65/1.48% (p = 0.95); MD - 1.55/- 1.37 dB (p = 0.19); foveal sensitivity 33.9/34.9 dB (p = 0.47); VFI 98.6/98.3% (p = 0.62); PSD 1.58/2.05 (p = 0.02); and test duration 297.17/298.57 s (p = 0.87); all respectively.

CONCLUSION

We identified a change in the PSD parameters in the trifocal IOL group. No other significant changes were identified in SAP parameters after implantation of trifocal AcrySof IQ PanOptix® and EDOF Tecnis Symfony® IOL. Longitudinal evaluation showed no changes in SAP after Trifocal and EDOF IOL implantation in normal subjects.

False Positive Responses in Standard Automated Perimetry

PURPOSE

To analyze the relationship between rates of false positive (FP) responses and standard automated perimetry results.

DESIGN

Prospective multicenter cross-sectional study.

METHODS

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).

RESULTS

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 r² values 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.

CONCLUSIONS

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.

Should clinical automated perimetry be considered for routine functional assessment of early/intermediate age-related macular degeneration (AMD)? A systematic review of current literature

Purpose

There is growing interest in functional testing for early/intermediate age‐related macular degeneration (iAMD). However, systematic evaluation of existing clinical functional tests is lacking. This systematic review examines evidence for using clinical automated perimetry in routine assessment of early/iAMD.

Recent findings

PubMed, Web of Science Core Collection, and Embase were searched from inception to October 2020 to answer, is there evidence of visual field defects in early/iAMD, and if so, are early/iAMD visual field defects linked to real‐world patient outcomes? Articles using clinical automated perimetry (commercially accessible and non‐modified devices/protocols) were included. Microperimetry was excluded as this has yet to be incorporated into clinical guidelines. The primary outcome was global visual field indices including mean deviation (MD), pattern standard deviation (PSD), mean sensitivity (MS) and frequency of defects. The secondary outcome was any real‐world patient outcome including quality of life and/or activities of daily living indices. Twenty‐six studies were eligible for inclusion and all studies were observational. There was consistent evidence of worsened MD, PSD, MS and frequency of defects for early/iAMD compared to normal eyes under photopic, low‐photopic and scotopic conditions. Meta‐analysis of studies using standard automated perimetry (SAP) under photopic conditions revealed worsened MD (−1.52dB [−2.27, −0.78 dB]) and MS (−1.47dB [−2, −0.94 dB]) in early/iAMD compared to normal eyes, representing large statistical effect sizes but non‐clinically meaningful reductions. There was insufficient data for meta‐analyses regarding other clinical automated perimetry protocols. Only one study assessed a real‐world patient outcome (on‐road driving performance), with no significant link to visual field outcomes in early/iAMD.

Summary

Significant reduction of global visual field indices is present in early/iAMD, but not clinically meaningful using SAP under photopic conditions. Translational relevance of visual field outcomes to patient outcomes in early/iAMD remains unclear. Thus, SAP under photopic conditions is unlikely to be useful for routine assessment of early/iAMD.

Trends in Utilization of Visual Field Tests for Glaucoma Patients: A Nationwide Study Using the Korean Health Insurance Review and Assessment Database

Purpose

To analyze 10-year trends in utilization of visual field tests for adult glaucoma or glaucoma-suspect patients using the Korean Health Insurance Review and Assessment data.

Methods

Health claims for the years 2010 to 2019, as recorded via Korea’s Health Insurance Review and Assessment service, were accessed. We identified glaucoma patients using the glaucoma diagnostic codes H40 (glaucoma) and H42 (glaucoma in other diseases classified elsewhere). For verification of the glaucoma diagnosis, information on any antiglaucoma medication prescriptions and ocular surgery history also was obtained. Visual field testing data was isolated using procedural codes E6690 (kinetic perimetry) and E6691 (standard automated perimetry [SAP]) performed in tertiary hospitals. Any changes in visual field test utilization were identified using regression trend analysis.

Results

From 2010 to 2019, the total number of SAP procedures performed in tertiary hospitals for either glaucoma or glaucoma-suspect patients increased gradually from 93,459 to 216,433. With regard to kinetic perimetry examinations, the total number decreased gradually from 6,364 to 3,792. The yearly average SAP number per patient showed a slight increase, from 1.168 to 1.248 (β = 0.008, R² = 0.669, p = 0.004). Meanwhile, the yearly average number of kinetic perimeter examinations per patient showed a significant decrease, from 1.093 to 0.940 (β = −0.013, R² = 0.580, p = 0.010).

Conclusions

Between 2010 and 2019, the yearly average number of SAP procedures performed per glaucoma or glaucoma-suspect patient increased in Korea. Meanwhile, the yearly average number of kinetic perimetry examinations per patient significantly decreased.

Viability of Performing Multiple 24-2 Visual Field Examinations at the Same Clinical Visit: The Frontloading Fields Study (FFS)

PURPOSE

To assess the viability, in terms of time taken for testing and repeatability, of frontloading (performing multiple perimetric examinations) in a single clinic visit.

DESIGN

Reliability enhancement analysis.

METHODS

A total of 329 healthy glaucoma suspect and glaucoma subjects within a glaucoma clinic undergoing perimetric testing using SITA-Faster twice for each eye within the same session were included. Global indices, pointwise sensitivity and probability scores, test duration, and reliability metrics were analysed.

RESULTS

For both tests 9.1% of right eye and 6.7% of left eye results were unreliable, with 58.4% and 67.5% of right and left eyes achieving reliable results, respectively; 83.8% of all subjects spent less than 20 minutes performing all tests. Differences in global indices, pointwise sensitivity and probability scores showed no systematic or clinically significant difference between tests one and two for each eye. There was also no systematic difference in the number of test locations identified as defective at the P < .05 level between tests. Test results that were unreliable tended to show more instances of a failed "cluster" criterion that were not repeatable.

CONCLUSIONS

Frontloading using SITA-Faster was viable for obtaining sets of reliable, repeatable perimetric data in terms of conventional outputs, overcoming practical issues regarding low test reliability using singleton results and confirmation of visual field defects. Despite the need to remain cognisant of the reliability of SITA-Faster, frontloading using this algorithm may be a practical method for meeting recommendations for multiple perimetric data required to make confident inferences about glaucoma state and progression.

Slowed Saccadic Reaction Times in Seemingly Normal Parts of Glaucomatous Visual Fields

Purpose: In eye movement perimetry, peripheral stimuli are confirmed by goal-directed eye movements toward the stimulus. The saccadic reaction time (SRT) is regarded as an index of visual field responsiveness, whereas in standard automated perimetry (SAP), the visual field sensitivity is tested. We investigated the relation between visual field sensitivity and responsiveness in corresponding locations of the visual field in healthy controls and in patients with mild, moderate and advanced glaucoma.

Materials and Methods: Thirty-four healthy control subjects and 42 glaucoma patients underwent a 54-point protocol in eye movement perimetry (EMP) and a 24-2 SITA standard protocol in a Humphrey Field Analyzer. The visual field points were stratified by total deviation sensitivity loss in SAP into 6 strata. A generalized linear mixed model was applied to determine the influence of the various factors.

Results: The generalized linear mixed model showed that the mean SRT increased with increasing glaucoma severity, from 479 ms in the control eyes to 678 ms in the eyes of patients with advanced glaucoma (p < 0.001). Mean SRTs significantly increased with increasing SAP sensitivity loss. Even at the locations where no sensitivity loss was detected by SAP (total deviation values greater or equal than 0 dB), we found lengthened SRTs in mild, moderate and advanced glaucoma compared to healthy controls (p < 0.05) and in moderate and advanced glaucoma compared to mild glaucoma (p < 0.05). At locations with total deviation values between 0 and −3 dB, −3 and −6 dB and −6 and −12 dB, we found similar differences.

Conclusions: The lengthened SRT in areas with normal retinal sensitivities in glaucomatous eyes, i.e., planning and execution of saccades to specific locations, precede altered sensory perception as assessed with SAP. Better understanding of altered sensory processing in glaucoma might allow earlier diagnosis of emerging glaucoma.

Long-Term Effectiveness and Safety of Tafluprost, Travoprost, and Latanoprost in Korean Patients with Primary Open-Angle Glaucoma or Normal-Tension Glaucoma: A Multicenter Retrospective Cohort Study (LOTUS Study)

This multicenter retrospective cohort study compared the effectiveness and safety of long-term tafluprost, travoprost, or latanoprost in patients with primary open-angle glaucoma (POAG) or normal-tension glaucoma (NTG). Data were extracted from electronic medical records of 300 patients treated with tafluprost, travoprost, or latanoprost for >6 months. Propensity matching for age and sex was used for effectiveness and safety comparisons. The primary endpoint was visual field (VF) progression via mean deviation (MD) slope. Secondary endpoints were change of MD, intraocular pressure, pattern standard deviation, VF index, and advanced glaucoma intervention study score. Treatment-related adverse events (AEs) were also compared between groups. Overall, 216 POAG or NTG patients were matched into Match Set 1 (72 patients/group), and 177 NTG-only patients in Match Set 2 (59 patients/group) according to: age (mean: 61, 62 years) and sex (male: 53, 56%). There were no statistically significant between-group differences regarding MD slope (p = 0.413, p = 0.374 in Match Sets 1 and 2, respectively). There were no significant between-group differences/tendencies regarding secondary endpoints. No AEs were serious, and there were no significant between-group differences regarding reported AEs. In patients with POAG or NTG, long-term tafluprost, travoprost, or latanoprost showed similar effects. All three prostaglandin analogs had good long-term safety profiles.

A Single Low-Dose of Methylphenidate Improves Abnormal Visual Field Testing

PURPOSE

To evaluate the effect of methylphenidate on visual field testing in healthy adults with abnormal visual field results.

METHODS

This prospective, randomized, controlled interventional clinical trial comprised all patients who had abnormal visual field test results and normal eye examination and ophthalmic history. Eligible patients were randomly assigned to either the study group or the control group. All patients repeated their visual field testing. Study group patients received a single dose of 10 mg methylphenidate prior to that. The main outcome measures were the percent difference in mean deviation and pattern standard deviation between the second and first visual fields.

RESULTS

The methylphenidate group had greater improvement in all parameters. Mean deviation improved by median 68% (IQR 19%-78%) in the methylphenidate group vs. 27% [-5% to 55%] in the controls. However, this was not statistically significant (p = .83). Pattern standard deviation improved by median 49% (22%-59%) vs. 7% [-9% to 45%], respectively (p = .012). The visual fields were also reviewed by 3 masked experienced ophthalmologists. They indicated that the second visual field improved in 76.2% of the methylphenidate group vs. 48.5% of the controls (p = .04). A normal repeat visual field occurred in 57.7% vs. 21.2%, respectively. A subgroup analysis of patients with prior experience in visual field testing yielded an even more striking improvement in the methylphenidate group vs. controls.

CONCLUSIONS

A single low dose of methylphenidate can improve visual field testing in subjects without ocular pathology, and even more in those with prior experience in perimetry.

A Novel Method of Visual Field Assessment for Patients with Unilateral Severely Limited Central Vision: A Pilot Study

Purpose

Reliable visual field testing requires the tested eye to be fixated on a central target. This poses a major obstacle for eyes with severe central vision loss. This pilot study assesses whether it may be feasible to examine such patients with a modified method.

Methods

A green filter was placed over the fellow eye. A FASTPAC algorithm was used with a red stimulus. The green filter prevented transmission of the red stimuli but allowed visualization of the yellow fixation light. Subjects were tested by both the conventional and the novel method, performed in a randomized order. We compared the reliability indices and also the precision of the two methods.

Results

We present results from six patients. The novel method was associated with an 85% reduction in fixation losses (P=0.028) and a 58% reduction in eye motion on gaze tracking (P=0.007). Further, specialized testing in one of the volunteers demonstrated that the novel technique could more precisely define a small zone of preserved peripheral vision (P=0.008).

Conclusion

The results of this pilot study suggest that the novel method described may be a feasible strategy for visual field testing in patients with unilateral severe central vision loss.

An artificial intelligence model for the simulation of visual effects in patients with visual field defects

Background

This study aimed to simulate the visual field (VF) effects of patients with VF defects using deep learning and computer vision technology.

Methods

We collected 3,660 Humphrey visual fields (HVFs) as data samples, including 3,263 reliable 24-2 HVFs. The convolutional neural network (CNN) analyzed and converted the grayscale map of reliable samples into structured data. The artificial intelligence (AI) simulations were developed using computer vision technology. In statistical analyses, the pilot study determined 687 reliable samples to conduct clinical trials, and the two independent sample t-tests were used to calculate the difference of the cumulative gray values. Three volunteers evaluated the matching degree of shape and position between the grayscale map and the AI simulation, which was graded from 0 to100 scores. Based on the average ranking, the proportion of good and excellent grades was determined, and thus the reliability of the AI simulations was assessed.

Results

The reliable samples in the experimental data consisted of 1,334 normal samples and 1,929 abnormal samples. Based on the existing mature CNN model, the fully connected layer was integrated to analyze the VF damage parameters of the input images, and the prediction accuracy of the damage type of the VF defects was up to 89%. By mapping the area and damage information in the VF damage parameter quintuple data set into the real scene image and adjusting the darkening effect according to the damage parameter, the visual effects in patients were simulated in the real scene image. In the clinical validation, there was no statistically significant difference in the cumulative gray value (P>0.05). The good and excellent proportion of the average scores reached 96.0%, thus confirming the accuracy of the AI model.

Conclusions

An AI model with high accuracy was established to simulate the visual effects in patients with VF defects.

Comparison of perimetric Glaucoma Staging Systems in Asians with primary glaucoma

BACKGROUND

To compare functional staging classifications in Vietnamese patients with primary open angle glaucoma (POAG) and chronic primary angle closure glaucoma (PACG).

METHODS

A retrospective cross-section study was conducted at a national setting. Two hundred seven eyes of 207 patients were recruited. Patients were tested with standard automated perimetry. Field loss was generally classified in four stages (normal, early, moderate, and severe), using four classification strategies: (1) Hodapp-Parrish-Anderson (HPA), (2) enhanced Glaucoma Staging System (eGSS), (3) modified Glaucoma Staging System (mGSS) and (4) the Advanced Glaucoma Intervention Study (AGIS). AGIS as a standard method was used to judge the staging performance of the other three classifications in terms of agreement (Cohen Kappa-K) and association (Chi-Square Test-Cramer's V).

RESULTS

The agreement between AGIS and mGSS (K = 0.687; p < 0.001) and HPA (K = 0.686; p < 0.001) was substantial while that between AGIS and eGSS was slight (K = 0.103; p < 0.001). The association between AGIS and mGSS (V = 0.748; p < 0.001) and HPA (V = 0.748; p < 0.001) was greater than eGSS (V = 0.594; p < 0.001).

CONCLUSIONS

MGSS and HPA showed stronger agreement and closer association with AGIS than eGSS. We recommend mGSS should be used in managing a glaucoma clinic because of its simplicity and convenience over HPA and AGIS.

A New System for Assessing Visual Disability Using a Digital Visor

Background: Considering the lack of universally accepted visual requirements for driving and for defining various grades of visual disability, the aim of this study is to propose a new method that provides a numerical score resulting from a combined assessment of the visual field and visual acuity loss obtained using a digital technology visor. Methods: This study presents a new system for calculating the percentage of visual disability by combining binocular visual acuity and binocular visual field assessments. A new Global Vision Evaluation System digital technology visor uses standardized, reproducible criteria to produce well-defined, numerically expressed test results. Through a specific algorithm, the device produces a numerical value expressing the percentage of visual disability. Results: Eighty-six subjects with various types of visual impairment underwent visual acuity and visual field test examinations carried out employing both traditional methods and the new digital visor. The two methods provided homogeneously similar results regarding the positioning of the subjects on the visual disability scale. Conclusions: The new digital visor seems to be a valid method to ensure that visual disability assessments are more homogeneous and reliable, and that, consequently, the resources available for this purpose are more fairly distributed.

Usefulness of data augmentation for visual field trend analyses in patients with glaucoma

AIM

To investigate the usefulness of data augmentation in visual field (VF) trend analyses in patients with glaucoma.

METHOD

This study included 6380 VFs from 638 eyes of 417 patients with open-angle glaucoma. Various affine transformations were applied to augment the VF data: (1) rotation, (2) scaling, (3) vertical and horizontal shift and (4) a combination of these different transformations. Using pointwise linear regression (PLR), the total deviation (TD) values of a patient's 10th VF were predicted using TD values from shorter VF series (from first to third VFs (VF1-3) to first to ninth VFs (VF1-9)) with and without VF data augmentation, and the root mean squared error (RMSE) was calculated.

RESULTS

With PLR, mean RMSE without VF augmentation averaged from 3.95 (VF1-3) to 19.01 (VF1-9) dB. The RMSE was significantly improved by applying the different transformations: (1) rotation (from VF1-3 to VF1-7), (2) scaling (from VF1-3 to VF1-6), (3) vertical and horizontal shifts (from VF1-3 to VF1-4) and (iv) a combination of these (from VF1-3 to VF1-7). Progression rates in VF1-10 had better agreement with those in shorter VF series when a combination of affine transformation was applied. The differences in rates were between 1.9 (VF1-3) and 0.39 (VF1-9) dB if augmentation was used, which was significantly smaller than that observed when augmentation was not applied (from 2.6 with VF1-3 to 0.26 dB with VF1-9).

CONCLUSION

It is useful to apply VF data augmentation techniques when predicting future VF progression in glaucoma using PLR, especially with short VF series.

Factors Predicting a Greater Likelihood of Poor Visual Field Reliability in Glaucoma Patients and Suspects

Purpose

Identify factors predicting worse or better than expected visual field (VF) performance.

Methods

A total of 10,262 VFs from 1538 eyes of 909 subjects with manifest or suspected glaucoma were analyzed. Linear mixed-effects models predicted mean deviation (MD) at each timepoint. Differences between observed and predicted MD (ΔMD) were calculated and logistic regression identified factors predicting lower than expected (ΔMD <-1 dB) or higher than expected (ΔMD >1 dB) sensitivity.

Results

Both higher and lower than expected sensitivity were more likely in VFs with severe compared with mild damage (relative risk [RR] >1.3, P < 0.05). Higher than expected sensitivity was more likely in VFs with moderate damage (RR = 2.57, P < 0.001). False-positive (FP) errors increased the likelihood of higher than expected sensitivity at all disease stages (RR >2.1 per 10% increase, P < 0.001), whereas false-negative (FN) errors increased the likelihood of lower than expected sensitivity in mild and moderate disease (RR >1.19 per 10% increase, P < 0.05). Fixation loss errors slightly increased the likelihood of higher than expected VF sensitivity in moderate and severe disease (RR >1.1 per 10% increase, P < 0.01). Longer test duration increased likelihood of lower than expected sensitivity at all disease stages (RR >1.36 per minute increase, P < 0.001). Lower than expected sensitivity was more likely in late afternoon tests (RR = 1.27, P < 0.01). A total of 26.6% of VFs had higher or lower than expected sensitivity in the absence of FPs, FNs, or fixation losses.

Conclusions

FPs, test duration, and FNs are the primary measures predicting if a VF is likely to be reliable, although tests with normal reliability measures may still be unreliable. Our results help clinicians judge VF reliability and highlight the need to integrate reliability measures with other clinical data when making treatment decisions.

Translational Relevance

This likelihood model derived from a large dataset helps clinicians identify VFs that may either falsely suggest disease progression or mask true worsening, thereby improving the utility of VFs in clinical practice.

Vision to improve: quality improvement in ophthalmology

Improving quality of care and patient outcomes is a professional duty of all health care workers. Quality improvement is a part of health policy, an accreditation requirement of residency programs, and a recognized sub-specialty in academic medicine. Given the increasing need for ophthalmological services with our aging population, it is critical for ophthalmologists and their staff to develop the necessary skills in quality improvement to ensure access to care that is safe, patient-centered, effective, efficient, equitable, and timely. This narrative review outlines tools that are used in a recognized framework, including the creation of an aim statement, Ishikawa diagram, Pareto analysis, process maps, Plan-Do-Study-Act cycles, and run charts. We also discuss common challenges that occur when conducting quality initiatives. Two quality improvement projects conducted in the Department of Ophthalmology at University of Toronto are used as examples to illustrate these tools. The aim of the first project was to improve visual field test reliability and the aim of the second was to ensure secure email communication between residents and staff in caring for emergency patients. This primer provides the foundations ophthalmologists and their staff can use to support and guide their quality improvement efforts.

Measuring degeneration of the lateral geniculate nuclei from pituitary adenoma compression detected by 7T ultra-high field MRI: a method for predicting vision recovery following surgical decompression of the optic chiasm

OBJECTIVE

Predicting vision recovery following surgical decompression of the optic chiasm in pituitary adenoma patients remains a clinical challenge, as there is significant variability in postoperative visual function that remains unreliably explained by current prognostic factors. Available literature inadequately characterizes alterations in adenoma patients involving the lateral geniculate nucleus (LGN). This study examined the association of LGN degeneration with chiasmatic compression as well as with the retinal nerve fiber layer (RNFL), pattern standard deviation (PSD), mean deviation (MD), and postoperative vision recovery. PSD is the degree of difference between the measured visual field pattern and the normal pattern ("hill") of vision, and MD is the average of the difference from the age-adjusted normal value.

METHODS

A prospective study of 27 pituitary adenoma patients and 27 matched healthy controls was conducted. Participants were scanned on a 7T ultra-high field MRI scanner, and 3 independent readers measured the LGN at its maximum cross-sectional area on coronal T1-weighted MPRAGE imaging. Readers were blinded to diagnosis and to each other's measurements. Neuro-ophthalmological data, including RNFL thickness, MD, and PSD, were acquired for 12 patients, and postoperative visual function data were collected on patients who underwent surgical chiasmal decompression. LGN areas were compared using two-tailed t-tests.

RESULTS

The average LGN cross-sectional area of adenoma patients was significantly smaller than that of controls (13.8 vs 19.2 mm2, p < 0.0001). The average LGN cross-sectional area correlated with MD (r = 0.67, p = 0.04), PSD (r = -0.62, p = 0.02), and RNFL thickness (r = 0.75, p = 0.02). The LGN cross-sectional area in adenoma patients with chiasm compression was 26.6% smaller than in patients without compression (p = 0.009). The average tumor volume was 7902.7 mm3. Patients with preoperative vision impairment showed 29.4% smaller LGN cross-sectional areas than patients without deficits (p = 0.003). Patients who experienced improved postoperative vision had LGN cross-sectional areas that were 40.8% larger than those of patients without postoperative improvement (p = 0.007).

CONCLUSIONS

The authors demonstrate novel in vivo evidence of LGN volume loss in pituitary adenoma patients and correlate imaging results with neuro-ophthalmology findings and postoperative vision recovery. Morphometric changes to the LGN may reflect anterograde transsynaptic degeneration. These findings indicate that LGN degeneration may be a marker of optic apparatus injury from chiasm compression, and measurement of LGN volume loss may be useful in predicting vision recovery following adenoma resection.

The Effect of Patient Characteristics and Sleep Quality on Visual Field Performance Reliability

Purpose

To investigate the association of automated visual field (VF) reliability indices (false positive [FP], false negative [FN], and fixation loss [FL]) and sleep quality, VF experience, and age.

Methods

Prospective, cross-sectional study. Adult patients (age ≥ 18 years) completing automated VF testing were invited to participate. Baseline participant characteristics were obtained, and all participants were asked to complete the Pittsburgh Sleep Quality Index (PSQI) questionnaire. Nonparametric Spearman correlations and logistical regression models were performed.

Results

63 patients were enrolled. Lower PSQI score was correlated with higher percentage (%) FL in the right eye (p = 0.03). Fewer prior VF was significantly correlated with higher %FP in the right eye (p = 0.008). Older age was significantly correlated with higher %FN in the left eye (p = 0.01). Greater mean deviation (MD) and pattern standard deviation (PSD) were strongly correlated with higher %FN in the right (p = 0.02 and 0.002, resp.) and left eyes (p = 0.01 and 0.02, resp.).

Conclusion

In this prospective, cross-sectional study, worse MD and PSD are strongly correlated with increased FN in both eyes. Increased FN in the left eye associated with older age might be attributable to test fatigue. Worse sleep quality is associated with decreased FL in the right eye.