Glaucoma is the leading cause of irreversible blindness, but its early symptoms are not obvious and are easily overlooked, so early screening for glaucoma is particularly important. The cup to disc ratio is an important indicator for clinical glaucoma screening, and accurate segmentation of the optic cup and disc is the key to calculating the cup to disc ratio. In this paper, a full convolutional neural network with residual multi-scale convolution module was proposed for the optic cup and disc segmentation. First, the fundus image was contrast enhanced and polar transformation was introduced. Subsequently, W-Net was used as the backbone network, which replaced the standard convolution unit with the residual multi-scale full convolution module, the input port was added to the image pyramid to construct the multi-scale input, and the side output layer was used as the early classifier to generate the local prediction output. Finally, a new multi-tag loss function was proposed to guide network segmentation. The mean intersection over union of the optic cup and disc segmentation in the REFUGE dataset was 0.904 0 and 0.955 3 respectively, and the overlapping error was 0.178 0 and 0.066 5 respectively. The results show that this method not only realizes the joint segmentation of cup and disc, but also improves the segmentation accuracy effectively, which could be helpful for the promotion of large-scale early glaucoma screening.
Diagnostic Techniques, Ophthalmological ; Fundus Oculi ; Glaucoma/diagnostic imaging* ; Humans ; Neural Networks, Computer ; Optic Disk/diagnostic imaging*

Glaucoma is one of blind causing diseases. The cup-to-disc ratio is the main basis for glaucoma screening. Therefore, it is of great significance to precisely segment the optic cup and disc. In this article, an optic cup and disc segmentation model based on the linear attention and dual attention is proposed. Firstly, the region of interest is located and cropped according to the characteristics of the optic disc. Secondly, linear attention residual network-34 (ResNet-34) is introduced as a feature extraction network. Finally, channel and spatial dual attention weights are generated by the linear attention output features, which are used to calibrate feature map in the decoder to obtain the optic cup and disc segmentation image. Experimental results show that the intersection over union of the optic disc and cup in Retinal Image Dataset for Optic Nerve Head Segmentation (DRISHTI-GS) dataset are 0.962 3 and 0.856 4, respectively, and the intersection over union of the optic disc and cup in retinal image database for optic nerve evaluation (RIM-ONE-V3) are 0.956 3 and 0.784 4, respectively. The proposed model is better than the comparison algorithm and has certain medical value in the early screening of glaucoma. In addition, this article uses knowledge distillation technology to generate two smaller models, which is beneficial to apply the models to embedded device.
Humans ; Optic Disk/diagnostic imaging* ; Glaucoma/diagnosis* ; Algorithms ; Diagnostic Techniques, Ophthalmological ; Databases, Factual

Objective To observe the role of ultrasound biomicroscopy(UBM)in two-year post-operative follow-up for primary open-angle glaucoma patients with modified CO
Carbon Dioxide ; Follow-Up Studies ; Glaucoma, Open-Angle/surgery* ; Humans ; Microscopy, Acoustic ; Sclera/diagnostic imaging* ; Treatment Outcome

PURPOSE: To compare the clinical and anterior segment anatomical features in primary angle closure sub-groups based on configurations of iris root insertion. METHODS: Primary angle closure patients were imaged using anterior segment optical coherence tomography. Anterior chamber depth, iris curvature, iris thickness (IT) at the scleral spur and 500, 750, and 1,500 µm from the scleral spur (IT(0), IT(500), IT(750), and IT(1500)), lens vault, iris area, angle opening distance (AOD(500)), angle recess area (ARA(750)), and trabecular iris space area (TISA(750)) were measured. Iris root insertion was categorized into a non-basal insertion group (NBG) and basal insertion group (BG). RESULTS: In total, 43 eyes of 39 participants belonged to the NBG and 89 eyes of 53 participants to the BG. The mean age of participants was greater in the NBG than the BG (62.7 ± 5.7 vs. 59.8 ± 7.3 years, p = 0.043), and the baseline intraocular pressure was higher in the BG than the NBG (16.4 ± 4.4 vs. 14.9 ± 3.3 mmHg, p = 0.037). The BG showed a greater IT(0) (0.265 ± 0.04 vs. 0.214 ± 0.03 mm, p < 0.001) and iris area (1.59 ± 0.24 vs. 1.52 ± 0.27 mm2, p = 0.045), lower ARA(750) (0.112 ± 0.08 vs. 0.154 ± 0.08 mm2, p = 0.017) and AOD(500) (0.165 ± 0.07 vs. 0.202 ± 0.08 mm, p = 0.014) compared to the NBG. CONCLUSIONS: The BG had a narrower anterior chamber angle, thicker peripheral iris, and higher pretreatment intraocular pressure.
Anterior Eye Segment/*diagnostic imaging ; Female ; Glaucoma, Angle-Closure/diagnosis/physiopathology/*surgery ; Gonioscopy ; Humans ; *Intraocular Pressure ; Iridectomy/*methods ; Iris/diagnostic imaging/*surgery ; Lens, Crystalline/diagnostic imaging ; Male ; Middle Aged ; Prospective Studies ; Tomography, Optical Coherence/*methods

BACKGROUNDPrimary angle-closure glaucoma (PACG) is a major cause of visual morbidity in East Asia. Dark-room provocative test (DRPT) has been used to determine which narrow angles have the risk to develop angle closure. However, the accuracy of DRPT might be altered because that after emerging from the dark room, the configuration of the angle is affected by the light of the slit-lamp and the appositionally closed angle reopens. The aim of this study was to examine the pupillary diameter in different light conditions and use it as a parameter to assess the accuracy of dark-room provocative test.

METHODSPatients with suspected primary angle-closure glaucoma undergoing DRPT were recruited. The anterior chamber angle was examined by anterior segment optical coherence tomography under the following conditions: (1) in standard room illumination; (2) after short-term dark-adaptation and (3) after DRPT. Mean values of pupil size and numbers of appositionally closed angle under different conditions were compared.

RESULTSA total of 47 eyes of 47 patients were analyzed. The pupil size after DRPT was smaller than that after short-term dark-adaptation (P < 0.001) and smaller than that in standard room illumination (P = 0.026). The numbers of appositionally closed angles after short-term dark-adaptation were significantly larger than those after DRPT (P < 0.001). There was no significant difference between the numbers of appositionally closed angles in standard room illumination and after DRPT (P = 0.157).

CONCLUSIONSConstriction of pupil size immediately after prolonged dark room provocative test may lead to change in the angle configuration, which may lead to false negative results. We suggest a modified protocol of recording intraocular pressure immediately after DRPT and performing gonioscopy following short-term dark adaptation to improve the accuracy of angle closure assessment.

Adult ; Aged ; Dark Adaptation ; Diagnostic Techniques, Ophthalmological ; Female ; Glaucoma, Angle-Closure ; diagnosis ; diagnostic imaging ; Humans ; Male ; Middle Aged ; Sensitivity and Specificity ; Ultrasonography

PURPOSE: To evaluate the influence of biometric variables on refractive outcomes after cataract surgery in angle-closure glaucoma (ACG) patients. METHODS: In this case-control study, 42 ACG patients, 40 open-angle glaucoma (OAG) patients, and 35 controls without glaucoma who had undergone conventional cataract surgery were enrolled consecutively. Electronic medical records, including preoperative biometric variables (keratometric diopter, axial length, anterior chamber depth, and lens thickness), the refractive change (RC), and the absolute value of refractive change (ARC) were reviewed. RESULTS: In the control and OAG patients, the anterior chamber depth was negatively correlated with the ARC (r = -0.344, p = 0.043 and r = -0.431, p = 0.006, respectively), whereas there was no correlation in the ACG patients. Lens thickness was positively correlated with the RC, but not with the ARC, in the control and OAG groups (r = 0.391, p = 0.020 and r = 0.501, p = 0.001, respectively). In contrast, lens thickness in the ACG group was not correlated with the RC but was positively correlated with the ARC (r = 0.331, p = 0.032). CONCLUSIONS: In contrast with the anterior chamber depth, preoperatively measured lens thickness may be a useful predictor of the direction of the RC after cataract surgery in control and OAG patients. However, in ACG patients, a thicker lens was correlated with a larger RC, regardless of the direction of the shift (hyperopic or myopic).
Aged ; Anterior Chamber/*diagnostic imaging ; Biometry/*methods ; Female ; Follow-Up Studies ; Glaucoma, Angle-Closure/*complications/diagnosis/surgery ; Glaucoma, Open-Angle/*complications/diagnosis/surgery ; Humans ; *Intraocular Pressure ; Male ; Middle Aged ; *Phacoemulsification ; Refraction, Ocular/*physiology ; Retrospective Studies ; Tomography, Optical Coherence

Background: Currently, spectral-domain optical coherence tomography (SD-OCT) appears to be a new type of glaucoma diagnostic tool. Thus, this study aimed to evaluate the effectiveness of glaucoma diagnostic parameters from SD-OCT of patients with different severities of myopia. Methods: This was a cross-sectional study. A total of 248 participants (248 eyes) were enrolled, including 51 cases in the early primary open-angle glaucoma group, 79 cases in the control group (0.50 D to -0.50 D, excluding -0.50 D), 47 cases in the low-myopic group (-0.50 to -3.00 D, excluding -3.00 D), 43 cases in the moderate-myopic group (-3.00 to -6.00 D, excluding -6.00 D), and 28 cases in the high-myopic group (≤-6.00 D). All participants were examined using the Humphrey visual field test and SD-OCT. The SD-OCT parameters of the retinal nerve fiber layer (RNFL) and ganglion cell complex were analyzed statistically using the receiver operating characteristic curve and area under the curve (AUC). Results: The AUC showed that the best parameters for the control and low-myopic groups were the inferior and inferior temporal RNFL thicknesses (AUC >0.94), respectively; for the moderate- and high-myopic groups, the best parameter was the temporal low RNFL thickness (AUC, 0.926 and 0.896, respectively). The AUC of the inferior parameters of the moderate-myopic group (0.864) was lower, ranked 15 among all RNFL parameters. When the sensitivity was fixed at 85%, the specificity of the inferior, superior, inferior temporal, and superior temporal quadrants was higher (>80%) in the control and low-myopic groups, while they were lower (20-60%) for the moderate- and high-myopia groups. The green color based on the OCT database was also less for the high-myopic group compared with that of other groups (P < 0.05). Conclusions Glaucoma diagnostic parameters from SD-OCT were not clinically effective for the moderate- and high-myopic groups. The specificities were low. The moderate- and high-myopic groups require comprehensive analyses for the diagnoses of glaucoma. The SD-OCT database should be improved to better indicate the level of myopia based on the corresponding diopter readings.
Aged ; Case-Control Studies ; Cross-Sectional Studies ; Female ; Glaucoma ; diagnostic imaging ; Glaucoma, Open-Angle ; Humans ; Male ; Middle Aged ; Nerve Fibers ; Optic Disk ; ROC Curve ; Retinal Ganglion Cells ; Tomography, Optical Coherence ; Visual Fields

PURPOSE: To investigate the relationship between vitamin D and glaucoma. METHODS: This retrospective, cross-sectional study included subjects who underwent a health screening at the Health Screening Center of Kangbuk Samsung Hospital from August 2012 to July 2013. All fundus photographs were reviewed by ophthalmologists. The ophthalmologists determined if an eye was glaucomatous based on the criteria set forth by the International Society of Geographical and Epidemiological Ophthalmology and by the appearance of the retinal nerve fiber layer and optic disc. If the subjects previously underwent an ophthalmologic examination, they were enrolled based on the documented history. In addition to fundus photographs, each participant underwent a systemic examination including blood sampling and sociodemographic and behavioral questionnaires. The subjects were divided into five groups according to serum 25-hydroxyvitamin D (25(OH)D) level. Multivariate logistic regression models were constructed to assess possible associations between elevated glaucoma risk and systemic factors with a p < 0.2 on univariate analysis. RESULTS: Of the 169,208 subjects older than 20 years, 123,331 were eligible for the study. There was no difference in the prevalence of glaucoma according to quintile of serum 25(OH)D level based on sex (p = 0.412 for males, p = 0.169 for females). According to the multivariable-adjusted logistic analysis, the odds ratio of glaucoma for the fourth quintile was significantly lower than that of the first quintile in females (odds ratio, 0.713; 95% confidence interval, 0.520 to 0.979). CONCLUSIONS: Lower 25(OH)D level was significantly associated with an elevated risk of glaucoma in females compared with higher 25(OH)D level. Further evaluation is needed to investigate the relationship between glaucoma and vitamin D.
Adult ; Cross-Sectional Studies ; Female ; Follow-Up Studies ; Glaucoma/diagnosis/*epidemiology/etiology ; Humans ; Incidence ; Intraocular Pressure ; Male ; Optic Disk/diagnostic imaging ; Prevalence ; Republic of Korea/epidemiology ; Retrospective Studies ; Vitamin D/*blood ; Vitamin D Deficiency/blood/complications/*epidemiology ; Young Adult

PURPOSE: To investigate the use of ganglion cell inner plexiform layer (GC-IPL) thickness, as measured by spectral domain optical coherence tomography, to detect central visual field (VF) progression. METHODS: This study included 384 eyes from 384 patients (219 preperimetric and 165 perimetric glaucomatous eyes; average follow-up, 4.3 years). Photographic assessment of retinal nerve fiber layer (RNFL) and serial VF analysis were performed to detect glaucoma progression in the central (within 10°) area. Study inclusion required at least five serial spectral domain optical coherence tomography exams at different visits. The long-term test-retest variability of average GC-IPL thicknesses was calculated in 110 stable preperimetric glaucomatous eyes. The sensitivity and specificity of GC-IPL measurements for the detection of central VF progression were calculated in an event-based analysis using the calculated variability as a cut-off and were compared with those of central RNFL photographic assessment. RESULTS: The intersession test-retest variability, defined as the 95% confidence interval, was 1.76 µm for average GC-IPL thickness. The sensitivity and specificity of the average GC-IPL thickness for detecting central VF progression were 60.7% and 78.9%, respectively. Among six sectors, the inferonasal GC-IPL sector showed the highest sensitivity (53.6%). The sensitivity of the ≥1 sector GC-IPL to detect central VF progression was significantly higher than that of central RNFL photographic progression (p = 0.013). Other GC-IPL parameters showed comparable sensitivity and specificity to detect central VF progression compared with RNFL photographic progression. CONCLUSIONS: Serial GC-IPL measurements show comparable performance in the detection of central glaucomatous VF progression to RNFL photographic assessment.
Disease Progression ; Female ; Follow-Up Studies ; Glaucoma/*diagnosis/physiopathology ; Humans ; *Intraocular Pressure ; Macula Lutea/*diagnostic imaging ; Male ; Middle Aged ; ROC Curve ; Retinal Ganglion Cells/*pathology ; Retrospective Studies ; Time Factors ; Tomography, Optical Coherence/*methods ; *Visual Fields