Animals ; Macaca mulatta ; Optic Disk ; Glaucoma ; Craniocerebral Trauma ; Intraocular Pressure ; Low Tension Glaucoma

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

INTRODUCTION: Detection of neurological conditions is of high importance in the current context of increasingly ageing populations. Imaging of the retina and the optic nerve head represents a unique opportunity to detect brain diseases, but requires specific human expertise. We review the current outcomes of artificial intelligence (AI) methods applied to retinal imaging for the detection of neurological and neuro-ophthalmic conditions. METHOD: Current and emerging concepts related to the detection of neurological conditions, using AI-based investigations of the retina in patients with brain disease were examined and summarised. RESULTS: Papilloedema due to intracranial hypertension can be accurately identified with deep learning on standard retinal imaging at a human expert level. Emerging studies suggest that patients with Alzheimer's disease can be discriminated from cognitively normal individuals, using AI applied to retinal images. CONCLUSION Recent AI-based systems dedicated to scalable retinal imaging have opened new perspectives for the detection of brain conditions directly or indirectly affecting retinal structures. However, further validation and implementation studies are required to better understand their potential value in clinical practice.
Humans ; Artificial Intelligence ; Brain/diagnostic imaging* ; Retina ; Optic Disk ; Aging

OBJECTIVE: To observe the effect of acupuncture on visual acuity, intraocular pressure, visual field, retinal and choroidal thickness on optic disc and macular area in patients with optic atrophy. METHODS: A total of 33 patients with optic atrophy were treated with acupuncture. Acupuncture was given at Chengqi (ST 1), Shangjingming (Extra), Qiuhou (EX-HN 7) and Fengchi (GB 20) etc., 30 min each time, once a day, for 14 days. The visual acuity, intraocular pressure, visual field indexes (mean deviation [MD], pattern standard deviation [PSD] and visual field index [VFI]), optic disc retinal nerve fiber layer thickness, macular retinal thickness and choroidal thickness of optic disc and sub-foveal were compared before and after treatment. RESULTS: Compared before treatment, the visual acuity was increased (P<0.05), the MD value was decreased (P<0.05), the thickness of nerve fiber layer on the upper temporal side of optic disc was thinner (P<0.05), and the choroidal thickness of average, nasal side and lower temporal side of optic disc was increased (P<0.05). There was significant correlation between visual field MD and retinal nerve fiber layer thickness in different quadrants before and after treatment (P<0.01). CONCLUSION Acupuncture could improve visual acuity, increase choroidal thickness in part of optic disc area in patients with optic atrophy.
Acupuncture Therapy ; Humans ; Optic Atrophy/therapy* ; Optic Disk/diagnostic imaging* ; Retina/diagnostic imaging* ; Tomography, Optical Coherence

The existing retinal vessels segmentation algorithms have various problems that the end of main vessels are easy to break, and the central macula and the optic disc boundary are likely to be mistakenly segmented. To solve the above problems, a novel retinal vessels segmentation algorithm is proposed in this paper. The algorithm merged together vessels contour information and conditional generative adversarial nets. Firstly, non-uniform light removal and principal component analysis were used to process the fundus images. Therefore, it enhanced the contrast between the blood vessels and the background, and obtained the single-scale gray images with rich feature information. Secondly, the dense blocks integrated with the deep separable convolution with offset and squeeze-and-exception (SE) block were applied to the encoder and decoder to alleviate the gradient disappearance or explosion. Simultaneously, the network focused on the feature information of the learning target. Thirdly, the contour loss function was added to improve the identification ability of the blood vessels information and contour information of the network. Finally, experiments were carried out on the DRIVE and STARE datasets respectively. The value of area under the receiver operating characteristic reached 0.982 5 and 0.987 4, respectively, and the accuracy reached 0.967 7 and 0.975 6, respectively. Experimental results show that the algorithm can accurately distinguish contours and blood vessels, and reduce blood vessel rupture. The algorithm has certain application value in the diagnosis of clinical ophthalmic diseases.
Algorithms ; Fundus Oculi ; Optic Disk ; ROC Curve ; Retinal Vessels/diagnostic imaging*

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*

PURPOSE: We investigated structural changes in the retina by using optical coherence tomography (OCT) in a feline model of retinal degeneration using iodoacetic acid (IAA).METHODS: We examined 22 eyes of 11 felines over 2 years of age. The felines had fasted for 12 hours and were intravenously injected with IAA 20 mg/kg of body weight. OCT (Spectralis OCT) was performed at the point where the ends of the retinal vessels collected in the lateral direction from the optic nerve head and area centralis. Similarly, OCT was performed four times at 1-week intervals following injections, at which point the felines were sacrificed and histologic examinations were performed. Using OCT, the thickness of each layer of the retina was measured.RESULTS: The average body weight of the three male and eight female felines investigated in this study was 1.61 ± 0.19 kg. The mean total retinal thickness of the felines before injection was 221.32 ± 9.82 µm, with a significant decrease in the retinal thickness at 2, 3, and 4 weeks following injections of 186.41 ± 35.42, 174.56 ± 31.94, and 175.35 ± 33.84 µm, respectively (p = 0.028, 0.027, and 0.027, respectively). The thickness of the outer nuclear layer was 57.49 ± 8.03 µm before injection and 29.26 ± 17.87, 25.62 ± 13.88, and 31.60 ± 18.38 µm at 2, 3, and 4 weeks, respectively, after injection (p = 0.028, 0.028, 0.046, respectively).CONCLUSIONS: In a feline model of retinal degeneration using IAA, the total retinal thickness and the thickness of the outer nuclear layer were shown to decrease significantly on OCT.
Angiography ; Body Weight ; Female ; Humans ; Iodoacetic Acid ; Male ; Optic Disk ; Photoreceptor Cells, Vertebrate ; Retina ; Retinal Degeneration ; Retinal Vessels ; Retinaldehyde ; Tomography, Optical Coherence

PURPOSE: To explore the progressive change and associated factors of optic disc tilt in young myopic glaucomatous eyes by analyzing long-term follow-up data.METHODS: Optic disc images were obtained from spectral-domain optical coherence tomography enhanced depth imaging from at least five different visits. At each visit, the disc tilt angle (DTA), defined as the angle between the Bruch's membrane opening plane and the optic canal plane, was estimated at the central frame that passes through the optic disc. Glaucoma progression was assessed on the basis of changes noted on serial optic disc and retinal nerve fiber layer photographs or changes in the visual field (VF). A linear mixed effect model was used to assess the influence of parameters (age, sex, baseline and follow-up intraocular pressure, retinal nerve fiber layer thickness, VF mean deviation, axial length, central corneal thickness), and presence of glaucomatous progression upon DTA change.RESULTS: A total of 26 eyes of 26 young myopic primary open-angle glaucoma patients (axial length >24.0 mm; mean age, 25.1 ± 4.0 years; mean follow-up, 3.3 ± 0.9 years) were included. DTA was 7.0 ± 3.4 degrees at baseline and 8.3 ± 3.8 degrees at last visit, which represents a significant difference (p < 0.001). Worse VF mean deviation (p < 0.001) and longer axial length (p = 0.006) were significantly associated with DTA increase.CONCLUSIONS: Young myopic glaucomatous eyes showed progressive optic disc tilting. Progressive optic disc tilting in young myopic glaucomatous eyes may be related to either continuous axial myopic shift or glaucomatous structural change.
Bruch Membrane ; Follow-Up Studies ; Glaucoma ; Glaucoma, Open-Angle ; Humans ; Intraocular Pressure ; Myopia ; Nerve Fibers ; Optic Disk ; Retinaldehyde ; Tomography, Optical Coherence ; Visual Fields

Glaucoma is a progressive degenerative disease of the optic nerve head, characterized by a specific pattern of axonal loss and visual field deterioration. This review aims at introducing the different novel pharmacologic agents for its treatment, as well as their mechanisms. Most glaucoma patients require lifelong care and individualized treatment. Intraocular pressure (IOP), which is regulated by aqueous humor production, outflow via the trabecular meshwork (parasympathomimetics only) and uveoscleral outflow pathways, is currently the only treatable target for glaucoma treatment. Conventional glaucoma medications are categorized as β blockers, α agonists, carbonic anhydrase inhibitors, parasympathomimetics, and prostaglandin analogues. The development of basic research-derived novel classes of pharmacologic agents features novel action mechanisms, which are different from those of conventional medications. New classes of recently approved or clinical trial-tested medications include Rho-kinase inhibitors, nitric oxide donors, adenosine agonists, and prostaglandin analogs targeting E-type prostanoid receptors, etc. Their integration and future development will facilitate the expansion and customization of therapeutic options.
Adenosine ; Aqueous Humor ; Axons ; Carbonic Anhydrase Inhibitors ; Glaucoma ; Humans ; Intraocular Pressure ; Nitric Oxide Donors ; Ocular Hypertension ; Optic Disk ; Parasympathomimetics ; Prostaglandins, Synthetic ; rho-Associated Kinases ; Trabecular Meshwork ; Visual Fields

PURPOSE: We report two patients diagnosed with a sinus thrombosis with papillary edema. CASE SUMMARY: Case 1 was a 27-year-old male who presented with complaints of headache and vomiting for 2 months and blurred vision in both eyes. The best-corrected visual acuity (BCVA) was 1.0 in the right eye and 1.0 in the left eye. A visual field (VF) examination revealed a binocular peripheral VF defect and optical coherence tomography (OCT) and a fundus examination indicated optic disc swelling in both eyes. Brain magnetic resonance imaging (MRI) showed no specific finding but magnetic resonance venography revealed filling defect signs in the transverse sinus and a cerebrospinal fluid examination indicated elevated intracranial pressure (ICP). Case 2 was a 54-year-old female who came to our hospital with suspicion of bilateral optic disc swelling. The BCVA was 0.9 in the right eye and 1.0 in the left eye. A VF examination revealed an inferior-temporal VF defect and blind spot enlargement in the right eye. OCT and a fundus examination showed optic disc swelling in both eyes. Brain MRI showed no specific finding but magnetic resonance venography revealed a decrease in blood flow in the transverse sinus, sigmoid sinus. A cerebrospinal fluid examination indicated elevated ICP. CONCLUSIONS: In the case of optic disc swelling in both eyes, a secondary cause of ICP elevation and the possibility of optic disc swelling due to sinus thrombosis should be considered, and brain MRI and venography are needed to distinguish these possibilities.
Adult ; Brain ; Cerebrospinal Fluid ; Colon, Sigmoid ; Edema ; Female ; Headache ; Humans ; Intracranial Hypertension ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Optic Disk ; Optic Nerve Diseases ; Papilledema ; Phlebography ; Sinus Thrombosis, Intracranial ; Telescopes ; Tomography, Optical Coherence ; Visual Acuity ; Visual Fields ; Vomiting