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

The bionic optic nerve can mimic human visual physiology and is a future treatment for visual disorders. Photosynaptic devices could respond to light stimuli and mimic normal optic nerve function. By modifying (Poly(3,4-ethylenedioxythio-phene):poly (styrenesulfonate)) active layers with all-inorganic perovskite quantum dots, with an aqueous solution as the dielectric layer in this paper, we developed a photosynaptic device based on an organic electrochemical transistor (OECT). The optical switching response time of OECT was 3.7 s. To improve the optical response of the device, a 365 nm, 300 mW·cm ^-2 UV light source was used. Basic synaptic behaviors such as postsynaptic currents (0.225 mA) at a light pulse duration of 4 s and double pulse facilitation at a light pulse duration of 1 s and pulse interval of 1 s were simulated. By changing the way light stimulates, for example, by adjusting the intensity of the light pulses from 180 to 540 mW·cm ^-2, the duration from 1 to 20 s, and the number of light pulses from 1 to 20, the postsynaptic currents were increased by 0.350 mA, 0.420 mA, and 0.466 mA, respectively. As such, we realized the effective shift from short-term synaptic plasticity (100 s recovery of initial value) to long-term synaptic plasticity (84.3% of 250 s decay maximum). This optical synapse has a high potential for simulating the human optic nerve.
Humans ; Quantum Dots ; Bionics ; Oxides ; Optic Nerve

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

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

OBJECTIVES: Dysthyroid optic neuropathy (DON) is a class of diseases that makes seriously endanger to the vision of patients with thyroid-associated ophthalmopathy. This study aims to observe the visual function changes in patients with DON, and to evaluate the diagnostic value of indicators diagnosing DON. METHODS: A retrospective study was conducted on 98 eyes of 49 patients with dysthyroid optic neuropathy (DON) who were treated in Xiangya Hospital of Central South University from January 2017 to December 2019. All patients were received the examination of best corrected visual acuity (BCVA), Humphrey visual field, visual evoked potential (VEP), and contrast sensitivity. Ninety-eight eyes were divided into a DON group (45 eyes) and a non-DON group (53 eyes). T-test was used to compare the related indicators between the 2 groups. The sensitivity and specificity of each indicator were analyzed by receiver operating characteristic (ROC) curve. RESULTS: The BCVA and visual field index (VFI) of the DON group were significantly lower than those of the non-DON group (all P<0.05). The mean deviation (MD) and pattern standard deviation (PSD) of the DON group were significantly higher than those of the non-DON group (all P<0.05). The low frequency contrast sensitivity (CSL), medium frequency contrast sensitivity (CSM), and high frequency contrast sensitivity (CSH) of the DON group were significantly lower than those of the non-DON group (all P<0.05), with CSH being particularly prominent. Compared with the non-DON group, at spatial frequencies of 15°, 30°, and 60°, the amplitude of N135 wave was significantly reduced, and the latency of N75 wave, P100 wave, and N135 wave was significantly prolonged in the DON group (all P<0.05); at spatial frequencies of 15° and 30°, the amplitude of P100 wave was significantly reduced in the DON group (P<0.05). The ROC curve analysis results showed that the area under the curve (AUC) of VFI, CSL, CSM, CSH and 15° P100 amplitude diagnosing DON were 0.812, 0.841, 0.880, 0.784, and 0.791, respectively, with CSM possessing the highest sensitivity and specificity. CONCLUSIONS The visual function of patients with DON is decreased. VFI, contrast sensitivity of low, medium, and high frequency, and 15° P100 wave amplitude might be effective indicators for early diagnosis of DON.
Humans ; ROC Curve ; Optic Nerve Diseases/complications* ; Retrospective Studies ; Evoked Potentials, Visual ; Graves Ophthalmopathy

OBJECTIVES: To investigate the characteristics and objective assessment method of visual field defects caused by optic chiasm and its posterior visual pathway injury. METHODS: Typical cases of visual field defects caused by injuries to the optic chiasm, optic tracts, optic radiations, and visual cortex were selected. Visual field examinations, visual evoked potential (VEP) and multifocal visual evolved potential (mfVEP) measurements, craniocerebral CT/MRI, and retinal optical coherence tomography (OCT) were performed, respectively, and the aforementioned visual electrophysiological and neuroimaging indicators were analyzed comprehensively. RESULTS: The electrophysiological manifestations of visual field defects caused by optic chiasm injuries were bitemporal hemianopsia mfVEP abnormalities. The visual field defects caused by optic tract, optic radiation, and visual cortex injuries were all manifested homonymous hemianopsia mfVEP abnormalities contralateral to the lesion. Mild relative afferent pupil disorder (RAPD) and characteristic optic nerve atrophy were observed in hemianopsia patients with optic tract injuries, but not in patients with optic radiation or visual cortex injuries. Neuroimaging could provide morphological evidence of damages to the optic chiasm and its posterior visual pathway. CONCLUSIONS Visual field defects caused by optic chiasm, optic tract, optic radiation, and visual cortex injuries have their respective characteristics. The combined application of mfVEP and static visual field measurements, in combination with neuroimaging, can maximize the assessment of the location and degree of visual pathway damage, providing an effective scheme for the identification of such injuries.
Humans ; Optic Chiasm/pathology* ; Visual Pathways/pathology* ; Visual Fields ; Evoked Potentials, Visual ; Random Amplified Polymorphic DNA Technique ; Hemianopsia/complications* ; Vision Disorders/pathology* ; Optic Nerve Injuries/diagnostic imaging* ; Brain Injuries, Traumatic/diagnostic imaging*

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

Acute methanol poisoning harms the optic nerve and central nervous system, can cause irreversible damage, even coma or death in severe cases. This article reported four cases of methanol poisoning. 3 patients mistakenly ingested industrial alcohol containing methanol, the most serious patient suffered from coma, vision loss and other symptoms, the blood methanol concentration was 869.3 μg/ml. Another patient was poisoning caused by inhalation of methanol, with symptoms such as total blindness in the right eye and decreased visual acuity in the left eye. After active supportive treatment, 2 patients had partial recovery of visual acuity, and 2 patients had no sequelae. This article discussed the clinical features, treatment and prognosis of optic nerve damage caused by methanol poisoning, in order to raise awareness of this disease.
Coma ; Follow-Up Studies ; Humans ; Methanol ; Optic Nerve ; Optic Nerve Injuries ; Poisoning/therapy*

OBJECTIVE: To investigate the therapeutic effect of Epothilone D on traumatic optic neuropathy (TON) in rats. METHODS: Forty-two SD rats were randomized to receive intraperitoneal injection of 1.0 mg/kg Epothilone D or DMSO (control) every 3 days until day 28, and rat models of TON were established on the second day after the first administration. On days 3, 7, and 28, examination of flash visual evoked potentials (FVEP), immunofluorescence staining and Western blotting were performed to examine the visual pathway features, number of retinal ganglion cells (RGCs), GAP43 expression level in damaged axons, and changes of Tau and pTau-396/404 in the retina and optic nerve. RESULTS: In Epothilone D treatment group, RGC loss rate was significantly decreased by 19.12% (P=0.032) on day 3 and by 22.67% (P=0.042) on day 28 as compared with the rats in the control group, but FVEP examination failed to show physiological improvement in the visual pathway on day 28 in terms of the relative latency of N2 wave (P=0.236) and relative amplitude attenuation of P2-N2 wave (P=0.441). The total Tau content in the retina of the treatment group was significantly increased compared with that in the control group on day 3 (P < 0.001), showing a consistent change with ptau-396/404 level. In the optic nerve axons, the total Tau level in the treatment group was significantly lower than that in the control group on day 7 (P=0.002), but the changes of the total Tau and pTau-396/404 level did not show an obvious correlation. Epothilone D induced persistent expression of GAP43 in the damaged axons, detectable even on day 28 of the experiment. CONCLUSION Epothilone D treatment can protect against TON in rats by promoting the survival of injured RGCs, enhancing Tau content in the surviving RGCs, reducing Tau accumulation in injured axons, and stimulating sustained regeneration of axons.
Animals ; Disease Models, Animal ; Epothilones ; Evoked Potentials, Visual ; Nerve Regeneration/physiology* ; Optic Nerve Injuries/metabolism* ; Rats ; Rats, Sprague-Dawley ; Retinal Ganglion Cells/physiology*

Objective To describe a rare case of acute lymphocytic leukemia (ALL) with optic nerve head tumor cell infiltration treated with external beam irradiation.
Precursor Cell Lymphoblastic Leukemia-Lymphoma ; Optic Nerve ; Radiotherapy