The Purpose of the study was to develop a deep residual learning algorithm to screen for glaucoma from fundus photography and measure its diagnostic performance compared to Residents in ...Ophthalmology. A training dataset consisted of 1,364 color fundus photographs with glaucomatous indications and 1,768 color fundus photographs without glaucomatous features. A testing dataset consisted of 60 eyes of 60 glaucoma patients and 50 eyes of 50 normal subjects. Using the training dataset, a deep learning algorithm known as Deep Residual Learning for Image Recognition (ResNet) was developed to discriminate glaucoma, and its diagnostic accuracy was validated in the testing dataset, using the area under the receiver operating characteristic curve (AROC). The Deep Residual Learning for Image Recognition was constructed using the training dataset and validated using the testing dataset. The presence of glaucoma in the testing dataset was also confirmed by three Residents in Ophthalmology. The deep learning algorithm achieved significantly higher diagnostic performance compared to Residents in Ophthalmology; with ResNet, the AROC from all testing data was 96.5 (95% confidence interval CI: 93.5 to 99.6)% while the AROCs obtained by the three Residents were between 72.6% and 91.2%.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
We sought to construct and evaluate a deep learning (DL) model to diagnose early glaucoma from spectral-domain optical coherence tomography (OCT) images.
Artificial intelligence diagnostic tool ...development, evaluation, and comparison.
This multi-institution study included pretraining data of 4316 OCT images (RS3000) from 1371 eyes with open angle glaucoma (OAG) regardless of the stage of glaucoma and 193 normal eyes. Training data included OCT-1000/2000 images from 94 eyes of 94 patients with early OAG (mean deviation > −5.0 dB) and 84 eyes of 84 normal subjects. Testing data included OCT-1000/2000 from 114 eyes of 114 patients with early OAG (mean deviation > −5.0 dB) and 82 eyes of 82 normal subjects. A DL (convolutional neural network) classifier was trained using a pretraining dataset, followed by a second round of training using an independent training dataset. The DL model input features were the 8 × 8 grid macular retinal nerve fiber layer thickness and ganglion cell complex layer thickness from spectral-domain OCT. Diagnostic accuracy was investigated in the testing dataset. For comparison, diagnostic accuracy was also evaluated using the random forests and support vector machine models. The primary outcome measure was the area under the receiver operating characteristic curve (AROC).
The AROC with the DL model was 93.7%. The AROC significantly decreased to between 76.6% and 78.8% without the pretraining process. Significantly smaller AROCs were obtained with random forests and support vector machine models (82.0% and 67.4%, respectively).
A DL model for glaucoma using spectral-domain OCT offers a substantive increase in diagnostic performance.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
We evaluated the usefulness of various regression models, including least absolute shrinkage and selection operator (Lasso) regression, to predict future visual field (VF) progression in glaucoma ...patients.
Series of 10 VFs (Humphrey Field Analyzer 24-2 SITA-standard) from each of 513 eyes in 324 open-angle glaucoma patients, obtained in 4.9 ± 1.3 years (mean ± SD), were investigated. For each patient, the mean of all total deviation values (mTD) in the 10th VF was predicted using varying numbers of prior VFs (ranging from the first three VFs to all previous VFs) by applying ordinary least squares linear regression (OLSLR), M-estimator robust regression (M-robust), MM-estimator robust regression (MM-robust), skipped regression (Skipped), deepest regression (Deepest), and Lasso regression. Absolute prediction errors then were compared.
With OLSLR, prediction error varied between 5.7 ± 6.1 (using the first three VFs) and 1.2 ± 1.1 dB (using all nine previous VFs). Prediction accuracy was not significantly improved with M-robust, MM-robust, Skipped, or Deepest regression in almost all VF series; however, a significantly smaller prediction error was obtained with Lasso regression even with a small number of VFs (using first 3 VFs, 2.0 ± 2.2; using all nine previous VFs, 1.2 ± 1.1 dB).
Prediction errors using OLSLR are large when only a small number of VFs are included in the regression. Lasso regression offers much more accurate predictions, especially in short VF series.
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).
...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.
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.
The MP-3 microperimeter has a similar test-retest reproducibility to the HFA but a better structure-function relationship.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
We recently constructed an algorithm to measure visual field (VF) using the variational Bayes linear regression (VBLR). This algorithm enabled a faster VF measurement than the Swedish interactive ...thresholding algorithm (SITA) standard while maintaining the test-retest reproducibility (Murata H, et al. Br J Ophthalmol 2021). The current study aimed to compare the structure-function relationship between the SITA standard and VBLR.
In 78 eyes of 56 patients with primary open-angle glaucoma, VF measurements were conducted using both SITA standard and VBLR VF, as well as spectral-domain optical coherence tomography. The structure-function relationship was investigated between visual sensitivity and circumpapillary retinal nerve fiber layer in the whole VF. This analysis was repeated for each of the 12 sectors (30 degrees). The strength of the structure-function relationship was evaluated using the second-order bias-corrected Akaike Information Criterion (AICc) index.
In the whole VF, AICc values of SITA standard and VBLR were 601.6 and 597.3, respectively. The relative likelihood that VBLR had a better structure-function relationship than the SITA standard was 88.2% (when the entire field was averaged) or 99.9% (when all test points were analyzed in the pointwise manner). With the sector-wise analysis, SITA standard had a better structure-function relationship than VBLR in 1 sector (Superior sector in the retina), whereas VBLR had a better structure-function relationship than SITA standard in 4 sectors (Supero-Nasal, Infero-Nasal, Inferior, and Infero-Temporal sectors) with >95% relative likelihood.
Although it depends on locations and similar between SITA standard and VBLR-VF, but VBLR-VF had a better structure-function relationship than the SITA standard overall.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To investigate differences in biomechanical properties focusing on stiffness parameters between normal, treatment-naïve primary open-angle glaucoma (POAG), and treated POAG eyes. Retrospective ...case-control study, This study included 46 treatment-naïve POAG eyes, 46 POAG eyes treated with prostaglandin analogues, and 49 normal eyes used as controls; matched in terms of age and axial length. Corneal hysteresis (CH) and corneal resistance factor (CRF) were measured using an ocular response analyzer (ORA). Fifteen biomechanical parameters were measured with the Corneal Visualization Scheimpflug Technology (Corvis ST), including biomechanical glaucoma factor (BGF) and two stiffness parameters of 'SP A1' and 'stress-strain index (SSI)', which were compared among the three groups. Additionally, the area under the curve (AUC) values of the receiver-operating curve to discriminate control and treatment-naïve POAG eyes were calculated for BGF and CH. Treatment-naïve POAG eyes had higher 'SSI' than normal eyes even after controlling for IOP (p < 0.05, Tukey-Cramer test). Treated POAG eyes had significantly lower CRF, and higher BGF than treatment-naïve POAG eyes. There were also significant differences in CH or SP A1 among the three groups. BGF and CH had similar AUC values (0.61 and 0.59). Treatment-naïve POAG eyes had stiffer corneas compared to normal eyes, which seemed to result from the material/structure of the cornea rather than higher intraocular pressure. Antiglaucoma topical medication alters biomechanical properties measured with Corvis ST. These results are important for understanding the pathogenesis and improving the management of POAG.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Abstract
Minimally invasive glaucoma surgery has expanded the surgical treatment options in glaucoma, particularly when combined with cataract surgery. It is clinically relevant to understand the ...associated postoperative changes in biomechanical properties because they are influential on the measurement of intraocular pressure (IOP) and play an important role in the pathogenesis of open-angle glaucoma (OAG). This retrospective case–control study included OAG patients who underwent cataract surgery combined with microhook ab interno trabeculotomy (µLOT group: 53 eyes of 36 patients) or iStent implantation (iStent group: 59 eyes of 37 patients) and 62 eyes of 42 solo cataract patients without glaucoma as a control group. Changes in ten biomechanical parameters measured with the Ocular Response Analyzer and Corneal Visualization Scheimpflug Technology (Corvis ST) at 3 and 6 months postoperatively relative to baseline were compared among the 3 groups. In all the groups, IOP significantly decreased postoperatively. In the µLOT and control groups, significant changes in Corvis ST-related parameters, including stiffness parameter A1 and stress‒strain index, indicated that the cornea became softer postoperatively. In contrast, these parameters were unchanged in the iStent group. Apart from IOP reduction, the results show variations in corneal biomechanical changes from minimally invasive glaucoma surgery combined with cataract surgery.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
We previously reported that the visual field (VF) prediction model using the variational Bayes linear regression (VBLR) is useful for accurately predicting VF progression in glaucoma (Invest ...Ophthalmol Vis Sci. 2014, 2018). We constructed a VF measurement algorithm using VBLR, and the purpose of this study was to investigate its usefulness.
122 eyes of 73 patients with open-angle glaucoma were included in the current study. VF measurement was performed using the currently proposed VBLR programme with AP-7700 perimetry (KOWA). VF measurements were also conducted using the Swedish interactive thresholding algorithm (SITA) standard programme with Humphrey field analyser. VF measurements were performed using the 24-2 test grid. Visual sensitivities, test-retest reproducibility and measurement duration were compared between the two algorithms.
Mean mean deviation (MD) values with SITA standard were -7.9 and -8.7 dB (first and second measurements), whereas those with VBLR-VF were -8.2 and -8.0 dB, respectively. There were no significant differences across these values. The correlation coefficient of MD values between the 2 algorithms was 0.97 or 0.98. Test-retest reproducibility did not differ between the two algorithms. Mean measurement duration with SITA standard was 6 min and 02 s or 6 min and 00 s (first or second measurement), whereas a significantly shorter duration was associated with VBLR-VF (5 min and 23 s or 5 min and 30 s).
VBLR-VF reduced test duration while maintaining the same accuracy as the SITA-standard.
To investigate the effects of cataract surgery on corneal biomechanics and intraocular pressure (IOP) measured with the updated Corvis ST tonometer (CST).
Prospective, interventional case series ...study.
This study included 39 eyes of 39 cataract patients. CST measurements were performed at presurgery (Pre) as well as 1 week (1W), 1 month (1M), and 3 months (3M) postsurgery. The following CST parameters were recorded: deformation amplitude max (DA max), DA ratio max 1 mm and 2 mm, integrated radius, stiffness parameter at applanation 1 (SP A1), Ambrosio relational thickness to the horizontal profile (ARTh), Corvis biomechanical index (CBI), central corneal thickness (CCT), noncorrected intraocular pressure (IOPnct), and biomechanically corrected IOP (bIOP). IOP was also measured with Goldmann applanation tonometry and the noncontact tonometer CT-90A. All measurements were compared at each period using the linear mixed model, with and without adjustment for bIOP and CCT.
All IOP measurements decreased over time (P < .01). CCT was increased at 1W and 3M (P < .01), whereas ARTh was decreased at 1W and 1M (P < .01), but returned to its Pre level at 3M. DA max and Integrated radius were increased at 3M (P < .01), whereas SP A1 was decreased at 3M (P < .01). CBI was increased at 1W (P < .01), but returned to its Pre level at 1M.
IOP and Corneal biomechanical properties are changed after cataract surgery. In particular, SP A1 decreases while DA max and integrated radius increase, even at 3M, suggesting a less stiff cornea.
•Corvis ST measured changes in corneal biomechanical properties after cataract surgery.•Stiffness parameter at applanation 1 decreases while maximum deformation amplitude and integrated radius increase after cataract surgery.•These changes suggest a less stiff cornea after cataract surgery.•Goldmann applanation tonometry–measured intraocular pressure was deceased.•Corvis ST's biomechanically corrected intraocular pressure was also decreased.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP