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1.
Acta Clin Croat ; 60(1): 10-15, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34588716

RESUMO

The aim was to determine differences of blink reflex in clinically definite multiple sclerosis (CDMS) and clinically isolated syndrome (CIS) in patients presented with symptoms and signs of brainstem impairment. The study included 20 patients diagnosed with CDMS, 20 with CIS, and 20 healthy controls. We recorded latencies of early (R1) and late component ipsilaterally (R2) and contralaterally (R2'), and occurrence of irritative component (R3). We analyzed data on sex, age, signs of brainstem impairment and magnetic resonance imaging (MRI) findings for the presence of brainstem demyelinating lesions. There was no statistically significant difference between patient groups according to sex, age, symptoms of brainstem involvement and MRI findings. There was no statistically significant difference in R1 component latencies and R2 latencies on the right side. Latencies of R2 on the left and R2' on the right were statistically longer in CDMS group. There was no difference in the appearance of R3 component. In conclusion, blink reflex was found to be a very sensitive and useful diagnostic tool in the assessment of brainstem structures, especially because abnormalities are seen not only in CDMS but also in CIS. Slowing of the late component as a sign of dysfunction in the efferent part of the reflex arc is not very specific but is a highly sensitive finding.


Assuntos
Piscadela , Esclerose Múltipla , Tronco Encefálico/diagnóstico por imagem , Diagnóstico Precoce , Humanos , Esclerose Múltipla/diagnóstico , Tempo de Reação
2.
Math Biosci Eng ; 18(5): 5146-5175, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34517482

RESUMO

The human tear film is rapidly established after each blink, and is essential for clear vision and eye health. This paper reviews mathematical models and theories for the human tear film on the ocular surface, with an emphasis on localized flows where the tear film may fail. The models attempt to identify the important physical processes, and their parameters, governing the tear film in health and disease.


Assuntos
Síndromes do Olho Seco , Piscadela , Humanos , Modelos Teóricos , Lágrimas
3.
Neuron ; 109(18): 2981-2994.e5, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34534455

RESUMO

The role of the cerebellum in predictive motor control and coordination has been thoroughly studied during movements of a single body part. In the real world, however, actions are often more complex. Here, we show that a small area in the rostral anterior interpositus nucleus (rAIN) of the mouse cerebellum is responsible for generating a predictive motor synergy that serves to protect the eye by precisely coordinating muscles of the eyelid, neck, and forelimb. Within the rAIN region, we discovered a new functional category of neurons with unique properties specialized for control of motor synergies. These neurons integrated inhibitory cutaneous inputs from multiple parts of the body, and their activity was correlated with the vigor of the defensive motor synergy on a trial-by-trial basis. We propose that some regions of the cerebellum are organized in poly-somatotopic "action maps" to reduce dimensionality and simplify motor control during ethologically relevant behaviors.


Assuntos
Piscadela/fisiologia , Núcleos Cerebelares/química , Núcleos Cerebelares/fisiologia , Extremidades/fisiologia , Movimento/fisiologia , Animais , Núcleos Cerebelares/citologia , Cerebelo/química , Cerebelo/citologia , Cerebelo/fisiologia , Previsões , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Optogenética/métodos , Gravação em Vídeo/métodos
4.
Comput Intell Neurosci ; 2021: 2747940, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335710

RESUMO

In high-paced and efficient life and work, fatigue is one of the important factors that cause accidents such as traffic and medical accidents. This study designs a feature map-based pruning strategy (PFM), which effectively reduces redundant parameters and reduces the time and space complexity of parallelized deep convolutional neural network (DCNN) training; a correction is proposed in the Map stage. The secant conjugate gradient method (CGMSE) realizes the fast convergence of the conjugate gradient method and improves the convergence speed of the network; in the Reduce stage, a load balancing strategy to control the load rate (LBRLA) is proposed to achieve fast and uniform data grouping to ensure the parallelization performance of the parallel system. Finally, the related fatigue algorithm's research and simulation based on the human eye are carried out on the PC. The human face and eye area are detected from the video image collected using the USB camera, and the frame difference method and the position information of the human eye on the face are used. To track the human eye area, extract the relevant human eye fatigue characteristics, combine the blink frequency, closed eye duration, PERCLOS, and other human eye fatigue determination mechanisms to determine the fatigue state, and test and verify the designed platform and algorithm through experiments. This system is designed to enable people who doze off, such as drivers, to discover their state in time through the system and reduce the possibility of accidents due to fatigue.


Assuntos
Big Data , Redes Neurais de Computação , Algoritmos , Piscadela , Simulação por Computador , Humanos
5.
Behav Neurosci ; 135(5): 622-628, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34323518

RESUMO

The developmental onset of aversive learning processes depends on complex interactions between endocrine, neural, and social influences. Emergence of avoidance conditioning in rat pups is triggered by elevated plasma corticosterone activating the amygdala. Further, the mother's ability to buffer the corticosterone response delays the onset of avoidance in ˜2-week-old pups. Eyeblink conditioning (EBC) also develops during the pre-weaning period. In previous work, little or no conditioning was observed on Day 17 for pups housed in the home cage with mother and littermates between training sessions, whereas pups isolated between training sessions did show some conditioning. This suggests that social buffering may also delay the onset of this form of aversive learning. In the present study with Day-17 pups, one session of periorbital shock, the typical EBC unconditioned stimulus for young rat pups, resulted in lower plasma corticosterone levels and neural activity in the central nucleus of the amygdale (CeA) of pups returned to the mother and homecage following the session as compared to pups isolated following the shock session. These findings demonstrate social buffering of the physiological response to aversive stimulus exposure under conditions of EBC and support the hypothesis that social buffering of early adverse experience may adjust the timing of emergence of EBC in rat pups. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Assuntos
Condicionamento Palpebral , Corticosterona , Tonsila do Cerebelo , Animais , Piscadela , Condicionamento Clássico , Feminino , Humanos , Mães , Ratos
6.
Sensors (Basel) ; 21(14)2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34300635

RESUMO

This paper reports on a mask-type sensor for simultaneous pulse wave and respiration measurements and eye blink detection that uses only one sensing element. In the proposed sensor, a flexible air bag-shaped chamber whose inner pressure change can be measured by a microelectromechanical system-based piezoresistive cantilever was used as the sensing element. The air bag-shaped chamber is fabricated by wrapping a sponge pad with plastic film and polyimide tape. The polyimide tape has a hole to which the substrate with the piezoresistive cantilever adheres. By attaching the sensor device to a mask where it contacts the nose of the subject, the sensor can detect the pulses and eye blinks of the subject by detecting the vibration and displacement of the nose skin caused by these physiological parameters. Moreover, the respiration of the subject causes pressure changes in the space between the mask and the face of the subject as well as slight vibrations of the mask. Therefore, information about the respiration of the subject can be extracted from the sensor signal using either the low-frequency component (<1 Hz) or the high-frequency component (>100 Hz). This paper describes the sensor fabrication and provides demonstrations of the pulse wave and respiration measurements as well as eye blink detection using the fabricated sensor.


Assuntos
Sistemas Microeletromecânicos , Piscadela , Frequência Cardíaca , Pressão , Respiração
7.
Transl Vis Sci Technol ; 10(8): 11, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34251425

RESUMO

Purpose: The purpose of this study was to evaluate the effects of temperature and blinking on contact lens (CL) dehydration using an in vitro blink model. Methods: Three silicone hydrogel (delefilcon A, senofilcon A, and comfilcon A) and two conventional hydrogel (etafilcon A and omafilcon A) CL materials were evaluated at 1 and 16 hours. The water content (WC) of the CLs was measured using a gravimetric method. Lenses were incubated on a blink model, internally heated to achieve a clinically relevant surface temperature of 35°C. An artificial tear solution (ATS) was delivered to the blink model at 4.5 µL/min with a blink rate of 6 blinks/min. A comparison set of lenses were incubated in a vial containing either 2 mL of ATS or phosphate-buffered saline (PBS) at 35°C. Results: Increasing temperature to 35°C resulted in a decrease in WC for all tested CLs over time (P ≤ 0.0052). For most CLs, there was no significant difference in WC over time between ATS or PBS in the vial (P > 0.05). With the vial system, WC decreased and plateaued over time. However, on the blink model, for most CLs, the WC significantly decreased after 1 hour but returned toward initial WC levels after 16 hours (P > 0.05). Conclusions: The reduction in WC of CLs on the eye is likely due to both an increase in temperature and dehydration from air exposure and blinking. Translational Relevance: This study showed that the novel, heated, in vitro blink model could be used to provide clinical insights into CL dehydration on the eye.


Assuntos
Piscadela , Lentes de Contato Hidrofílicas , Desidratação , Humanos , Lágrimas , Temperatura
8.
Artigo em Inglês | MEDLINE | ID: mdl-34310312

RESUMO

Accurate eye blink artifact detection is essential for electroencephalogram (EEG) analysis and auxiliary analysis of nervous system diseases, especially in the presence of the frontal epileptiform discharges. In this paper, we develop a novel eye blink artifact detection algorithm based on optimally selected multi-dimensional EEG features. Specific efforts have been paid to filtering the frontal epileptiform discharges, where an unsupervised learning exploiting the EEG signal physiological characteristics and smooth nonlinear energy operator (SNEO) based on the K-means clustering has been firstly proposed. Multiple statistical EEG features derived from the frontal electrodes and other electrodes are then extracted to characterize eye blink artifacts. Discriminative feature selection scheme based on the variance filtering and Relief algorithms has been respectively studied, and the average correlation coefficient (ACC) is applied for feature optimization evaluation. The eye blink artifact detection is finally achieved based on the support vector machine (SVM) trained on the optimized EEG features. The effectiveness of the proposed algorithm is demonstrated by experiments carried out on the EEG database of 11 subjects recorded from the Children's Hospital, Zhejiang University School of Medicine (CHZU). Comparisons to several state-of-the-art (SOTA) eye blink artifact detection methods are also presented.


Assuntos
Artefatos , Processamento de Sinais Assistido por Computador , Algoritmos , Piscadela , Criança , Eletroencefalografia , Humanos
9.
Neuroscience ; 471: 72-79, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34332014

RESUMO

Recent evidence raised the importance of the cerebellum in emotional processes, with specific regard to negative emotions. However, its role in the processing of face emotional expressions is still unknown. This study was aimed at assessing whether face emotional expressions influence the cerebellar learning processes, using the delay eyeblink classical conditioning (EBCC) as a model. Visual stimuli composed of faces expressing happy, sad and neutral emotions were used as conditioning stimulus in forty healthy subjects to modulate the cerebellum-brainstem pathway underlying the EBCC. The same stimuli were used to explore their effects on the blink reflex (BR) and its recovery cycle (BRRC) and on the cerebellar-brain inhibition (CBI). Data analysis revealed that the learning component of the EBCC was significantly reduced following the passive view of sad faces, while the extinction phase was modulated by both sad and happy faces. By contrast, BR, BRRC and CBI were not significantly affected by the view of emotional face expressions. The present study provides first evidence that the passive viewing of faces displaying emotional expressions, are processed by the cerebellum, with no apparent involvement of the brainstem and the cerebello-cortical connection. In particular, the view of sad faces, reduces the excitability of the cerebellar circuit underlying the learning phase of the EBCC. Differently, the extinction phase was shortened by both happy and sad faces, suggesting that different neural bases underlie learning and extinction of emotions expressed by faces.


Assuntos
Piscadela , Expressão Facial , Cerebelo , Condicionamento Clássico , Emoções , Humanos
10.
J Occup Health ; 63(1): e12237, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34085344

RESUMO

OBJECTIVES: The present study was conducted to evaluate the status of tear film objectively and subjectively in machine carpet weavers. METHODS: In this cross-sectional study, machine-made carpet weavers were compared with the controls who were selected from people working in other parts of the factory except for the production. A complete evaluation of ocular health was done for all participants. The blink rate, tear deformation Time (TDT), and ocular staining were evaluated as an objective assessment and the ocular surface disease index (OSDI) was used for a subjective assessment of the tear film status. The results were compared between the two groups using the SPSS software. RESULTS: The results of 46 weavers (mean age: 38.43 ± 6.10 years) and 46 controls (mean age: 33.20 ± 8.40 years) were analyzed. The mean of blink rate and OSDI score were significantly higher in weavers (Blink rate: 20.67 ± 4.18 blink/min, OSDI: 22.59 ± 9.51) in comparison with controls (Blink rate: 14.00 ± 3.30 blink/min, OSDI: 6.22 ± 4.78, P < .001). The mean TDT value of the weavers was significantly lower compared with the controls (10.27 ± 3.01 and 16.58 ± 4.18 s respectively, P < .001). Ocular surface staining was seen among 60.9% of weavers while there was 6.5% in the controls (P < .001). Based on the TDT test and OSDI results together, the percentage of dry eye in the weavers was 43.5% and that in the non-weavers was 2.2%, which showed that the relationship between weaving and dry eyes was statistically significant (P < .001). CONCLUSIONS: The results indicate that increased symptoms and decreased tear stability in weavers compared with non-weavers lead to more tear film abnormalities in these individuals.


Assuntos
Síndromes do Olho Seco/diagnóstico , Pisos e Cobertura de Pisos , Doenças Profissionais/diagnóstico , Exposição Ocupacional/efeitos adversos , Indústria Têxtil , Adulto , Piscadela , Estudos Transversais , Técnicas de Diagnóstico Oftalmológico , Síndromes do Olho Seco/epidemiologia , Síndromes do Olho Seco/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/epidemiologia , Doenças Profissionais/etiologia , Lágrimas
11.
Comput Methods Programs Biomed ; 208: 106171, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34102561

RESUMO

BACKGROUND AND OBJECTIVE: Eyestrain has been increasingly severe in our lives and works as the progress of computers and smartphones. Evaluating eyestrain helps to prevent and relieve eyestrain. Our study aimed to evaluate eyestrain by analyzing vertical electrooculogram (VEOG). METHODS: 21 young subjects were asked to watch a video on the computer for a totally 120 minutes each, during which the VEOG signal was acquired using only three electrodes, and the questionnaire was answered every 30 minutes. The VEOG signal was divided into four 30-minute phases, from which VEOG signal power probability (VEOGSPP) features and blink features were extracted. The blink features include the changes of blink number (BN), group blinks number (GBN) and ratio (GBR), mean blink amplitude (Mean_BA) and duration (Mean_BD), mean blink duration at 50% (Mean_BD50), mean closing duration (Mean_CD) and opening duration (Mean_OD), mean opening duration at early 50% (Mean_ODE50) and late 50% (Mean_ODL50), mean blink maximum rising slope (Mean_BMRS) and falling slope (Mean_BMFS). RESULTS: The results showed that the VEOGSPP in the high-frequency band (0.8-6.3Hz), BN, GBN, and GBR significantly increased while the VEOGSPP in the low-frequency band (0.1-0.4Hz), Mean_BA, Mean_OD, and Mean_ODL50 significantly decreased with eyestrain (P<0.05). CONCLUSIONS: In conclusion, eyestrain induced by watching videos for a long time could be well evaluated by analyzing the VEOG signal.


Assuntos
Astenopia , Piscadela , Computadores , Eletroculografia , Humanos , Smartphone
12.
Biophys J ; 120(16): 3527-3537, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34181902

RESUMO

Phagocytosis is an important part of innate immunity and describes the engulfment of bacteria and other extracellular objects on the micrometer scale. The protrusion of the cell membrane around the bacteria during this process is driven by a reorganization of the actin cortex. The process has been studied on the molecular level to great extent during the past decades. However, a deep, fundamental understanding of the mechanics of the process is still lacking, in particular because of a lack of techniques that give access to binding dynamics below the optical resolution limit and cellular viscoelasticity at the same time. In this work, we propose a technique to characterize the mechanical properties of cells in a highly localized manner and apply it to investigate the early stages of phagocytosis. The technique can simultaneously resolve the contact region between a cell and an external object (in our application, a phagocytic target) even below the optical resolution limit. We used immunoglobulin-G-coated microparticles with a size of 2 µm as a model system and attached the particles to the macrophages with holographic optical tweezers. By switching the trap on and off, we were able to measure the rheological properties of the cells in a time-resolved manner during the first few minutes after attachment. The measured viscoelastic cellular response is consistent with power law rheology. The contact radius between particle and cell increased on a timescale of ∼30 s and converged after a few minutes. Although the binding dynamics are not affected by cytochalasin D, we observed an increase of the cellular compliance and a significant fluidization of the cortex after addition of cytochalasin D treatment. Furthermore, we report upper boundaries for the length- and timescale, at which cortical actin has been hypothesized to depolymerize during early phagocytosis.


Assuntos
Piscadela , Pinças Ópticas , Fagocitose , Reologia , Viscosidade
13.
Neuroscience ; 468: 168-175, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34147564

RESUMO

Although conditioned pain modulation (CPM) is considered to represent descending pain inhibitory mechanisms triggered by noxious stimuli applied to a remote area, there have been no previous studies comparing CPM between pain and tactile systems. In this study, we compared CPM between the two systems objectively using blink reflexes. Intra-epidermal electrical stimulation (IES) and transcutaneous electrical stimulation (TS) were applied to the right skin area over the supraorbital foramen to evoke a nociceptive or a non-nociceptive blink reflex, respectively, in 15 healthy males. In the test session, IES or TS were applied six times and subjects reported the intensity of each stimulus on a numerical rating scale (NRS). Blink reflexes were measured using electromyography (R2). The first and second sessions were control sessions, while in the third session, the left hand was immersed in cold water at 10 °C as a conditioning stimulus. The magnitude of the R2 blink and NRS scores were compared among the sessions by 2-way ANOVA. Both the NRS score and nociceptive R2 were significantly decreased in the third session for IES, with a significant correlation between the two variables; whereas, TS-induced non-nociceptive R2 did not change among the sessions. Although the conditioning stimulus decreased the NRS score for TS, the CPM effect was significantly smaller than that for IES (p = 0.002). The present findings suggest the presence of a pain-specific CPM effect to a heterotopic noxious stimulus.


Assuntos
Piscadela , Estimulação Elétrica Nervosa Transcutânea , Estimulação Elétrica , Humanos , Masculino , Nociceptividade , Dor , Medição da Dor , Limiar da Dor , Reflexo
14.
Neurosci Bull ; 37(8): 1147-1159, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33991316

RESUMO

While the hippocampus has been implicated in supporting the association among time-separated events, the underlying cellular mechanisms have not been fully clarified. Here, we combined in vivo multi-channel recording and optogenetics to investigate the activity of hippocampal interneurons in freely-moving mice performing a trace eyeblink conditioning (tEBC) task. We found that the hippocampal interneurons exhibited conditioned stimulus (CS)-evoked sustained activity, which predicted the performance of conditioned eyeblink responses (CRs) in the early acquisition of the tEBC. Consistent with this, greater proportions of hippocampal pyramidal cells showed CS-evoked decreased activity in the early acquisition of the tEBC. Moreover, optogenetic suppression of the sustained activity in hippocampal interneurons severely impaired acquisition of the tEBC. In contrast, suppression of the sustained activity of hippocampal interneurons had no effect on the performance of well-learned CRs. Our findings highlight the role of hippocampal interneurons in the tEBC, and point to a potential cellular mechanism subserving associative learning.


Assuntos
Condicionamento Palpebral , Animais , Piscadela , Condicionamento Clássico , Hipocampo , Interneurônios , Camundongos , Células Piramidais
15.
J Plast Reconstr Aesthet Surg ; 74(7): 1436-1445, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33952434

RESUMO

Facial palsy can cause the impairment of eye closure and affect blink, ocular health, communication, and esthetics. Dynamic surgical procedures can restore eye closure in patients with decreased facial nerve function. There are no standardized measures of voluntary and spontaneous eye closure that are used to evaluate the outcomes of blink restoration procedures. The purpose of this systematic literature review was to identify the measures used to assess normal and abnormal eye closure and blinking in patients with facial palsy. A literature search of the PubMed database using the keyword "facial nerve/surgery" was conducted. Only English language articles that pertain to the use of facial paralysis assessment systems published in the past 20 years, which involve eyelid closure were included. There were 57 articles that used a facial paralysis classification system with an eyelid closure component: House-Brackmann Facial Nerve Grading Scale (n = 43, 67%); Sunnybrook Facial Grading Scale (n = 9); palpebral fissure heights (n = 4), and the electronic clinician-graded facial function tool (n = 3) and three additional measures were reported once. Although the Terzis and Bruno Scoring System, blink ratio, and electronic, clinician-graded facial function scale(eFACE) Clinician-Graded Scoring System were valid measures of eyelid closure, there was no one comprehensive eye assessment that demonstrated all aspects of eye closure in facial palsy, which include closure amplitude, spontaneity, and quality of life. For blink assessment, eFACE is the most comprehensive tool currently available and recommended to be used with a patient-reported quality of life supplement that captures the specific domains related to facial nerve dysfunction.


Assuntos
Piscadela/fisiologia , Pálpebras/inervação , Nervo Facial/cirurgia , Paralisia Facial/cirurgia , Procedimentos Neurocirúrgicos , Pálpebras/fisiopatologia , Paralisia Facial/fisiopatologia , Humanos , Recuperação de Função Fisiológica
16.
J Fr Ophtalmol ; 44(7): 1029-1037, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34045106

RESUMO

PURPOSE: Blinking plays an important role in protecting the eyes, and the use of computers has been associated with a reduction in the blink rate. The goal of this study was to evaluate the effect of a virtual reality headset on blinking and lipid layer thickness and to compare these data to those associated with a conventional desktop monitor. METHODS: Two experiments were performed to compare the effect of 20minutes of use of a virtual reality headset (FOVE) and 20minutes of use of a desktop monitor on the frequency and length of blinks (experiment 1, 15 participants) and on the thickness of the lipid layer as measured by Lipiview (experiment 2, 12 participants). RESULTS: In the first experiment, the blink rate [F(1.83)=4.3, P=0.04, ß=0.36] and duration [F(1.83)=13, P=0.001, ß=0.35] increased with time under both conditions, but no statistical difference was found between the two conditions (headset vs. desktop monitor) either for blink rate [rmANOVA F(1.11)=0.01, P=0.92; headset: 15.1 blinks, 95% CI: 12.6 to 17.6 blinks; desktop: 14.6 blinks, 95% CI: 13.6 to 15.7 blinks] or for blink duration [rmANOVA F(1.11)=4.534, P=0.06; headset: 205.75ms, 95% CI: 200.9 to 210.6ms; desktop: 202.82ms, 95% CI: 198.2 to 207.5ms]. However, strong individual variations were observed. Evaluation of simulator sickness and visual fatigue by questionnaire showed no significant differences between the two conditions (SSQ simulator sickness questionnaire: V=46, P=0.62; VFQ visual fatigue questionnaire: V=15.5, P=0.13). In the second experiment, the lipid layer thickness increased significantly after use of the VR headset [F(1.18)=11.03, P=0.004, headset: 76.2nm, desktop: 58.8nm]. CONCLUSION: In terms of recommendations, the effect of virtual reality headsets on blink duration and frequency during a moderate exposure (20minutes) is comparable to that of a conventional desktop monitor. However, the strong individual variations observed, the lack of reliable tests to evaluate this individual sensitivity, and the significant increase in lipid layer thickness in experiment 2 suggest the value of a more detailed investigation, in particular with consideration of a longer exposure time and other tear film parameters.


Assuntos
Síndromes do Olho Seco , Realidade Virtual , Piscadela , Humanos , Lipídeos , Lágrimas
17.
Graefes Arch Clin Exp Ophthalmol ; 259(9): 2795-2805, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34003361

RESUMO

PURPOSE: To quantitatively evaluate the lipid layer thickness (LLT) and blinking in children with or without allergic conjunctivitis (AC), and to compare those between the different types of AC. METHODS: For this case-control study, 81 children with symptomatic AC with an average age of 9.62 ± 2.67 years were enrolled and subdivided according to the subtypes of AC, including seasonal/perennial allergic conjunctivitis group and vernal keratoconjunctivitis (VKC)/atopic keratoconjunctivitis (AKC) group. Another 82 age-matched healthy children were enrolled as control group. All subjects underwent routine eye examination and measurements of LLT, the number of incomplete or total blinking, partial blinking rate by the LipiView interferometer over a 10-s period. Other ocular surface assessment included fluorescein tear breakup time (TBUT), lower tear meniscus height, meibomian gland loss (MGL), meibum expressibility and quality. RESULTS: Pediatric patients with AC had significant thinner LLT, shorter TBUT, decreased total blinking but increased partial blinking rate, especially in those with VKC/AKC (all P < 0.05). A significant deterioration of meibomian gland parameters was observed in AC group when compared with control subjects, demonstrated by severe upper and lower MGL, lid margin abnormalities, decreased meibum expressibility, and abnormal meibum quality, all of which were worse in the severe type of AC (all P < 0.05). Thinner LLT was significantly correlated with decreased TBUT (ß = 3.666, P < 0.001) and severity of upper MGL (ß = - 7.701, P = 0.002). CONCLUSION: Decreased LLT and blinking disorders in pediatric patients with AC may contribute to lipid layer deficiency in the long run, which should be considered and appropriately diagnosed for a more precise treatment.


Assuntos
Conjuntivite Alérgica , Síndromes do Olho Seco , Piscadela , Estudos de Casos e Controles , Criança , Conjuntivite Alérgica/diagnóstico , Humanos , Interferometria , Lipídeos , Glândulas Tarsais/diagnóstico por imagem , Lágrimas
18.
Neural Netw ; 141: 87-97, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33873012

RESUMO

Event cameras contain emerging, neuromorphic vision sensors that capture local-light​ intensity changes at each pixel, generating a stream of asynchronous events. This way of acquiring visual information constitutes a departure from traditional frame-based cameras and offers several significant advantages - low energy consumption, high temporal resolution, high dynamic range and low latency. Driver monitoring systems (DMS) are in-cabin safety systems designed to sense and understand a drivers physical and cognitive state. Event cameras are particularly suited to DMS due to their inherent advantages. This paper proposes a novel method to simultaneously detect and track faces and eyes for driver monitoring. A unique, fully convolutional recurrent neural network architecture is presented. To train this network, a synthetic event-based dataset is simulated with accurate bounding box annotations, called Neuromorphic-HELEN. Additionally, a method to detect and analyse drivers' eye blinks is proposed, exploiting the high temporal resolution of event cameras. Behaviour of blinking provides greater insights into a driver level of fatigue or drowsiness. We show that blinks have a unique temporal signature that can be better captured by event cameras.


Assuntos
Piscadela , Tecnologia de Rastreamento Ocular , Redes Neurais de Computação , Fotografação , Humanos , Masculino
19.
Eye Contact Lens ; 47(7): 388-393, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33840748

RESUMO

PURPOSE: To evaluate active lysozyme deposition on daily disposable (DD) contact lenses (CL) using a novel in vitro blink model. METHODS: Three conventional hydrogel DD CL materials (etafilcon A, omafilcon A, nelfilcon A) and three silicone hydrogel DD CL materials (delefilcon A, senofilcon A, somofilcon A) were tested. The device blink rate was set to 6 blinks/min with a tear flow rate of 1 µL/min using an artificial tear solution (ATS) containing lysozyme and other typical tear film components. After incubation at 2, 4, or 8 hr, lenses were removed, and lysozyme activity was measured. A separate experiment was conducted with lenses incubated in a static vial containing 480 µL of ATS. RESULTS: Etafilcon A deposited significantly higher amounts of active lysozyme (402±102 µg/lens) than other lens materials after 8 hr (P<0.0001). Etafilcon A had a higher amount of active lysozyme using the blink model compared with the static vial (P=0.0435), whereas somofilcon A (P=0.0076) and senofilcon A (P=0.0019) had a higher amount of lysozyme activity in the vial compared with the blink model. CONCLUSION: The blink model can be tuned to provide quantitative data that closely mimics ex vivo studies and can be used to model deposition of lysozyme on CL materials.


Assuntos
Lentes de Contato Hidrofílicas , Muramidase , Piscadela , Humanos , Silicones , Lágrimas
20.
Eye Contact Lens ; 47(8): 442-444, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33900215

RESUMO

OBJECTIVES: Decreased blink rate during video display viewing (VDV) has been reported; however, patients with tear dysfunction often complain of more frequent blinking. The objectives were to compare blink rates during conversation and VDV in normal and dry eyes and correlate blink rates with signs and symptoms. METHODS: Blink rate was measured with an infrared blink sensor for 2 minutes during conversation and for 2 minutes while watching a video clip (VDV) in patients without dry eye disease (control, n=18) and in patients with tear dysfunction from meibomian gland dysfunction (MGD, n=23), conjunctivochalasis (CCh, n=19), and aqueous tear deficiency (n=34; non-Sjögren syndrome n=18 and Sjögren syndrome n=16). Patients completed visual analogue questionnaires assessing irritation frequency and severity and blink frequency and underwent an ocular surface evaluation. Group comparisons and correlations were calculated. RESULTS: Compared with control, conversational and VDV blink rates were significantly higher in CCh and aqueous tear deficiency (P≤0.005). Self-reported blink frequency was higher in all tear dysfunction groups compared with control. The VDV blink rate was significantly lower than the conversation blink rate in the control group (P=0.006) but not in any of the tear dysfunction groups. Conversational and VDV blink rates were significantly correlated with irritation frequency and severity. CONCLUSIONS: Blink rate decreases during VDV in normal eyes; however, this blink rate suppression was not observed in patients with tear dysfunction, perhaps because of their irritation symptoms or tear instability.


Assuntos
Síndromes do Olho Seco , Ceratoconjuntivite Seca , Disfunção da Glândula Tarsal , Piscadela , Síndromes do Olho Seco/diagnóstico , Humanos , Glândulas Tarsais , Lágrimas
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