Blink Research Articles

Laser acupuncture and photobiomodulation therapy in Bell’s palsy with a duration of greater than 8 weeks: a randomized controlled trial

To investigate the efficacy of laser acupuncture and photobiomodulation therapy in alleviating symptoms among patients diagnosed with Bell’s palsy with duration of greater than 8 weeks. The randomized controlled trial has been performed from May 2021 to April 2023. Patients were eligible who had Bell’s palsy with duration of greater than 8 weeks on out-patient Department of Otorhinolaryngology in Beijing Tongren Hospital. The laser acupuncture group received class IV laser treatment for 3 times per weeks, a total of 72 times. The control group received the same treatment procedure except the laser parameter. The primary outcome measures comprised House–Brackmann facial nerve grading system and electroneurography. Secondary outcome measures comprised Sunnybrook facial grading system, electromyography, and the blink reflex. A total of 84 participants were included (42 control group, 42 laser acupuncture group). After treatment, House–Brackmann facial nerve grading system (OR, 0.11; 95% CI, 0.04–0.30; P < 0.001), and the pathologic numbers of electroneuronography were statistically different between the laser acupuncture group and control group, including orbicularis oculi (OR,0.08; 95% CI, 0.02–0.21; P < 0.001), Frontalis muscle (OR,0.14; 95% CI, 0.05–0.39; P < 0.001), Orbicularis oris (OR,0.13; 95% CI, 0.04–0.36; P < 0.001), Ala nasi muscle (OR,0.06; 95% CI, 0.02–0.18; P < 0.001). In secondary outcomes, Sunnybrook facial grading system, has significant difference between the two groups (20.26; 95% CI, 14.69 to 25.83; P < 0.01). Latency by ENoG, include orbicularis oculi (-0.61; 95% CI, -0.43 to -0.09; P < 0.001), frontalis muscle (-0.12; 95% CI, -0.21 to -0.03; P < 0.01), orbicularis oris (-0.28; 95% CI, -0.41 to -0.16; P < 0.001), and ala nasi muscle (-0.26; 95% CI, -0.38 to -0.16; P < 0.001). All amplitudes of MUAPs and durations by electromyography (EMG) showed statistically significant differences compared with the control group after treatment. For the frontalis muscle, the amplitude of MUAPs was -64.23 (95% CI, -80.89 to -47.56; P < 0.001) and duration was -1.18 (95% CI, -1.49 to -0.87; P < 0.001). For orbicularis oris, amplitude of MUAPs was -29.82 (95% CI, -55.03 to -4.62; P = 0.02) and duration was -0.57 (95% CI, -0.94 to -0.20; P < 0.001). For depressor angulli oris, amplitude of MUAPs was -47.06 (95% CI, -62.15 to -31.97; P < 0.001) and duration was -2.21 (95% CI, -2.69 to -1.72; P < 0.001). Blink reflex, including R1 (OR, 0.03; 95% CI, 0.01–0.16; P < .001), R2 (OR, 0.04; 95% CI, 0.004–0.29; P < .001), and R2 latency differences (OR, 0.15; 95% CI, 0.05–0.51; P < .001), have significant difference between the two groups, respectively. The findings suggest that laser acupuncture relieve symptoms for patients with Bell’s palsy with a duration of greater than 8 weeks.Trial registration: ClinicalTrials.gov Identifier: NCT05846217.

Ocular toxicity associated with anti-HER2 agents in breast cancer: A pharmacovigilance analysis using the FAERS database.

Anti-human epidermal growth factor receptor 2 (HER2) agents have exhibited pronounced tumor-inhibitory activity, yet the accompanying ocular toxicity has frequently been underestimated. We aim to conduct a comprehensive comparative analysis of ocular toxicity risk related to various anti-HER2 agents. We executed a retrospective pharmacovigilance investigation based on the FDA Adverse Event Reporting System (FAERS) database, covering the period from Q2 2018 to Q1 2023. The disproportionality analysis was performed to assess ocular toxicity risk. Multivariate logistic regression was implemented to mitigate potential biases. Moreover, the time to onset of ocular toxicity was also evaluated. A total of 3467 ocular adverse event (AE) reports concerning anti-HER2 agents were collected. At the preferred term (PT) level, there were 69 positive signals, among which excessive eye blinking, abnormal sensation in the eye, and asthenopia presented a significant risk. In comparison to tyrosine kinase inhibitors (TKIs), antibody drugs were associated with a broader range of ocular disorders at Standardized MedDRA Queries (SMQ)levels, including conjunctival disorders, corneal disorders, ocular infections, ocular motility disorders, optic nerve disorders, and retinal disorders. In terms of onset time, pertuzumab displayed an earlier onset at 21.5 days, while trastuzumab deruxtecan had the latest at 91.5 days. In summary, our study reveals varying degrees of ocular toxicity related to anti-HER2 agents, with a significantly higher risk observed in antibody drugs. Additionally, novel ocular toxicity signals, not documented in product labels, have been detected. In the future, further research will be necessary to validate our findings.

The effect of incomplete blinking rate on corneal epithelial remodeling after trans-PRK surgery: a six-month study.

To evaluate the impact of incomplete blink rate on corneal epithelial thickness after transepithelial photorefractive keratectomy (Trans-PRK) surgery. Trans-PRK patients were divided into two groups based on preoperative incomplete blinking rates, namely rates ≤0.5 (41 right eyes, group A) and rates >0.5 (65 right eyes, group B). We used anterior segment optical coherence tomography to measure the corneal epithelial thickness (CET) and lipiview to measure the number of blinks, incomplete blinking rate, and lipid layer thickness (LLT). In both groups, CET decreased at 1 week and 1 month, and the thicknesses in the IT, T, and ST regions exceeded the preoperative levels. Three months after Trans-PRK, the thickness exceeded the preoperative levels and continued to increase during subsequent follow-ups. The blinking times and LLT in both groups decreased at 1 week and gradually increased but did not return to preoperative levels. Group A maintained an incomplete blinking rate of over 0.5 at all postoperative periods. The incomplete blinking rate of group B remained above 0.5 postoperatively, although there was an improvement compared with preoperative rates. Both groups showed a correlation between changes in CET and incomplete blinking rate. There was a correlation between changes in LLT and the incomplete blinking rate after surgery. Both groups showed uneven corneal epithelia thickening, which became more pronounced approaching the peripheral areas. In addition, changes in CET after surgery were positively correlated with the incomplete blinking rate in both patient groups. There was a negative correlation between postoperative LLT and incomplete blinking rate.

The Gluten-Casein-Free Diet in Children with Autism: A Clinical Results of the Ophthalmic and Behavioral Manifestations

Aim: To evaluate the ophthalmic and behavioral effects of a gluten-free casein-free diet (GCFD) in autism spectrum disorder (ASD). Method: The study was conducted from November 2020 to January 2023. We designed an 8-week clinical trial of GCFD on corneal reflex, pupil size, body mass index (BMI), weight, Autistic Disorder Index, Communication, Social interaction, and Stereotype Behavior. Results: A total of thirty participants completed the trial. GCFD reduced BMI [%95 CI -4.8895 to -2.1305 (P &amp;lt; 0.0001)], weight [%95 CI -8.5153 to -0.0647 (P = 0.0467)], Autistic Disorder Index [%95 CI -28.0359 to -16.2841 (P &amp;lt; 0.0001)], Communication [%95 CI -3.3325 to -1.6675 (P &amp;lt; 0.0001)], Social Interaction [%95 CI -4.3190 to -2.4010 (P &amp;lt; 0.0001)], and Stereotype Behavior [%95 CI -2.3939 to -0.2461 (P =0.01)] significantly. GCFD also reduced left [%95 CI -2.2421 to -1.6779 (P &amp;lt;0.0001)] and right pupil size [%95 CI -2.2999 to -1.7201 (P &amp;lt;0.0001)] significantly. Conversely, corneal reflex was significantly increased [95% CI 0.2159 to 2.1241 (P = 0.01)]. No differences were observed for IPD. Conclusion: This study suggested that the GCFD can effectively control ASD behaviors as well as regulate autonomic functions related to ophthalmic markers such as pupil size and corneal reflex, but more research is needed.

Prepulse inhibition and the call alert in emergency medical services.

In emergency medical services, paramedics are informed of an emergency call by a high-intensity acoustic alarm called the "call alert." Sudden, loud sounds like the call alert may cause a startle response and be experienced as aversive. Studies have identified an association between the call alert and adverse health effects in first responders; conceivably, these adverse health effects might be reduced by modifying the call alert to blunt its startling and aversive properties. Here, we assessed whether the call alert causes a startle response and whether its startling and aversive properties are reduced when the call alert is preceded by a weak acoustic "prepulse," a process referred to as "prepulse inhibition" (PPI). Paramedics (n = 50; 34M:13F:3 not reported; ages 20-68) were exposed to four call alerts (two with and two without a prepulse) in counterbalanced order. Responses were measured using electromyography (measuring blink amplitude), visual analog scales (quantifying perceived call alert intensity and aversiveness), and an electrocardiogram (assessing heart rate). Paramedics responded to the call alert with a startle reflex blink and an increased heart rate. Acoustic prepulses significantly reduced the amplitude of the call alert-induced startle blink, the perceived sound intensity, and the perceived "dislike" of the call alert. These findings confirm that the call alert is associated with an acoustic startle response in paramedics; adding a prepulse to the call alert can reduce its startling and aversive properties. Conceivably, such reductions might also diminish adverse health effects associated with the call alert in first responders.

Evaluation of Brain Stem Function in Diabetics with and Without Distal Symmetrical Polyneuropathy Using the Blink Reflex

Background: Diabetic peripheral neuropathy (DPN) is the commonest complication of T2DM. Neuropathy is a descriptor for a spectrum of clinical and subclinical symptoms with varying anatomical distributions, clinical histories, and perhaps underlying pathogenetic mechanisms. The distal Symmetrical sensory polyneuropathy is chronic, symmetrical, length-dependent sensorimotor. Studies of the blink reflex have shown potential as a method of assessing brainstem activity. Objective: The primary purpose of this research was to assess the function of the blink reflex in the early detection of cranial nerves and brain stem dysfunction in diabetes patients with and without polyneuropathy. We also aimed to see whether there were differences in blink reflex abnormalities between diabetes individuals with and without polyneuropathy. Patients and Methods: The study included a group of sixty-60 diabetic patients. Clinician and electrophysiologist evaluations were used to determine the severity of neuropathy. Patients with diabetes were separated into two groups: those with and without neuropathy. Results: A statistically significant difference between the two groups was for C.R.2 latency, and I.R.2 latency with a P-value &lt;0.001. Except for blink reflex’s R1 latency (P-value &gt;0.2), all other Blink reflex parameters were statistically different between patients who experience diabetic neuropathy and those who didn’t. Regarding HbA1c, a significant positive association with IR2 latency and C.R.2 latency was noted (Pvalue &lt;0.001) and also, a statistically significant negative association was found with I.R.2 duration and C.R.2 duration (P-value &lt;0.001). Amplitudes of sural, tibial and peroneal nerves were negatively associated with Blink reflex Latencies and positively associated with blink reflex duration. Conclusion: In conclusion, blink-reflex parameters (including ipsi-lateral R.2 latency, contra-lateral R.2 latency) are significantly associated with HBA1C level and degree of peripheral diabetic neuropathy. Received Sept. 2022 Accepted Nov. 2023 Published Jan. 2024

Contribution of TRPM8‐mediated activity to thermally‐evoked reflex blink

Purpose: To study the characteristics of reflex blink evoked by cold and heat stimulation of the ocular surface (OS), and to define the contribution of TRPM8 to the process.Methods: The orbicularis oculi muscle electromyography signal (OOemg) and the ocular surface temperature (OST; measured with a small thermoprobe placed on the cornea) were recorded in anaesthetised rats. OS temperature changes (ΔT) were induced by topical instillation of 20 μL drops of saline solution at different temperatures (15–50°C). ΔT and the area under the curve (AUC) and duration of the evoked OOemg signals were analysed before (control) and after topical treatment with the TRPM8 antagonist N‐(3‐aminopropyl)‐2‐[(3‐methylphenyl) methoxy] ‐N‐(2‐thienylmethyl) benzamide hydrochloride (AMTB; 1 mM).Results: Mild (−ΔT 0.1–5°C) and intense (−ΔT 5–15°C) cooling always evoked a reflex OOemg signal (probability = 1). AMTB significantly reduced the probability of cooling to evoke blink (probability = 0.26 and 0.57 for mild and intense cold stimuli, respectively; p &lt; 0.001). OOemg AUC and duration were also significantly reduced by AMTB (p &lt; 0.01). Probability of evoking OOemg signal by mild (ΔT 0.1–5°C) and intense (ΔT 5–15°C) OS heating was low (0.30 and 0.59 respectively), and their duration and AUC were significantly smaller than those evoked by cooling (p &lt; 0.001). Although AMTB did not modify the probability of heating stimuli to evoke OOemg signals (0.17 and 0.57 for mild and intense heating, respectively), the duration of signals evoked by mild heating stimuli was significantly increased (p &lt; 0.001).Conclusions: Cold stimuli applied to the ocular surface always evoked reflex EMG activity of the lid muscle. This ability of cooling stimuli to evoke reflex blink is mediated by TRPM8 channels, whose pharmacological blockade reduces both the probability to evoke the reflex blink and its amplitude.Support: PID2020‐115934RB‐I00 from DOI: MCIN/AEI/10.13039/50110001103; CIPROM/2021/48 from Generalitat Valenciana, Spain.

Характеристика полисинаптической рефлекторной возбудимости ствола головного мозга у больных с экзогенно-конституциональным ожирением

The purpose — to study the characteristics of polysynaptic reflex excitability of the brain stem based on an electroneuromyographic research of the blink reflex in patients with exogenous constitutional obesity (ECO). Material and methods. 288 women (mean age 37.5 (2.8) years) with ECO and 45 healthy women of the same age group were examined. All patients underwent a clinical and anthropometric examination, including quantitative indicators of body size and weight and electroneuromyographic study of the blink reflex (BR). Results. The anthropometric study revealed the presence of two variants of fat deposition topography — android (AT) and gynoid (GT) types. The ratio of ECO-AT and ECO-GT in this sample was 41.28% and 58.72%, respectively. Patients with ECO-GT showed a significant increase in the duration of the R2 component of the BR (44.1 (1.5) ms) (p &lt;0.01), a reduction in its latency (35.5 (0.8) ms) (p &lt; 0.05) and a decrease in the threshold (1.9 (0.1) mA) (p &lt; 0.01) compared to the indicators of healthy subjects. A direct significant correlation was found between the level of polysynaptic reflex excitability and the level of obesity (r = 0.75, p &lt; 0.05). The data obtained characterize the role of a lack of inhibition processes in the central nervous system and a functional deficit of the sensorimotor component in the ECO development mechanisms, with a disorder of autonomic nervous system and behavioural and emotional disorders, including eating behavior. As the degree of obesity increases, as well as with a more unfavorable pathogenetic type of ECO, the severity of changes in polysynaptic reflex excitability of the brain stem also increases. Conclusions. The study of polysynaptic reflex excitability of the brain stem by electroneuromyographic BR testing shows the role of dysfunction of the CNS suprasegmental parts in the ECO development and progression.

Orbital Structure Involvement in Midface Fractures Impacting Ocular Injury at a Tertiary Hospital in Eastern Indonesia

ABSTRACT Introduction: The midface is a complex anatomical area consisting of several areas. Although various factors protect the eye from trauma, such as orbital rim, blink reflex, elasticity of ocular structures, and protective eye movements by hands and head, ocular injuries remain common in patients with midface fractures, with an incidence rate of up to 90.6%. This study, the first of its kind conducted in Indonesia, aims to evaluate the characteristics and incidence of ocular injuries in midface fractures and to examine the relationship between the treatment. Methods: This observational analytic study employed a retrospective cohort design, utilizing medical record data of midface fracture patients. The independent variables included age, sex, cause, incidence, segment and severity of ocular injury, number of orbital wall involvements, and treatment options. The dependent variable was midface fracture patients. The Mann–Whitney and Fisher’s exact tests were employed to analyze the multivariate data. Results: Individuals aged 32–37 were most commonly affected due to accidents, with the anterior ocular segment and maxilla bone frequently affected. There are no special factors that differentiate a person from experiencing an ocular injury in a midface fracture (P &gt; 0.05). Ocular injuries correlated with orbital wall injury (P = 0.008) at least one discontinuity. Impaired functions included movement and visual disturbances, diplopia, and dystopia (P = 0.134). Conclusions: No significant relationship was found between age, sex, and cause of trauma with ocular injuries in patients with midface fractures. However, a significant relationship was observed between the amount of orbital rim involvement and at least one wall discontinuity occurring in midface fracture patients.

Advancing Intraoperative Neurophysiological Monitoring With Human Reflexes.

Human reflexes are simple motor responses that are automatically elicited by various sensory inputs. These reflexes can provide valuable insights into the functioning of the nervous system, particularly the brainstem and spinal cord. Reflexes involving the brainstem, such as the blink reflex, laryngeal adductor reflex, trigeminal hypoglossal reflex, and masseter H reflex, offer immediate information about the cranial-nerve functionality and the overall state of the brainstem. Similarly, spinal reflexes such as the H reflex of the soleus muscle, posterior root muscle reflexes, and sacral reflexes provide crucial information about the functionality of the spinal cord and peripheral nerves. One of the critical benefits of reflex monitoring is that it can provide continuous feedback without disrupting the surgical process due to no movement being induced in the surgical field. These reflexes can be monitored in real time during surgical procedures to assess the integrity of the nervous system and detect potential neurological damage. It is particularly noteworthy that the reflexes provide motor and sensory information on the functional integrity of nerve fibers and nuclei. This article describes the current techniques used for monitoring various human reflexes and their clinical significance in surgery. We also address important methodological considerations and their impact on surgical safety and patient outcomes. Utilizing these methodologies has the potential to advance or even revolutionize the field of intraoperative continuous monitoring, ultimately leading to improved surgical outcomes and enhanced patient care.

Mindspeak: Empowering Communication with Brain Keyboard

Brain-Computer Interface (BCI) technology stands as a groundbreaking innovation, revolutionizing the way individuals with severe motor disabilities interact with the world. The integration of Electroencephalogram (EEG) sensors within applications like the Brain Keyboard marks a pivotal stride forward. By capturing and interpreting brain signals triggered by simple actions such as eye blinking, these sensors empower users to control a virtual keyboard, transcending the limitations imposed by traditional motor pathways. This direct channel between the human brain and external devices offers an unprecedented avenue for communication, particularly invaluable for those grappling with conditions like paralysis or locked-in syndrome. The profound impact of BCIs extends far beyond facilitating textual communication; they represent a lifeline, a bridge toward autonomy and engagement for individuals facing profound physical challenges. Through these interfaces, users can articulate thoughts, express emotions, and actively participate in social interactions, fundamentally enhancing their quality of life. This technological marvel not only breaks down communication barriers but also holds promise in broader applications. As BCIs evolve, their potential encompasses enabling control over robotic prosthetics, granting users the ability to accomplish tasks once deemed impossible. Moreover, the implications of BCIs stretch into the realm of neuroscience, offering a unique window into understanding cognitive processes and neurological disorders. The ability to decode and interpret brain activity not only aids in facilitating communication but also paves the way for groundbreaking research and potential therapies. Challenges persist, such as enhancing signal accuracy and streamlining usability, yet the remarkable benefits that BCIs offer to individuals with motor disabilities continue to fuel ongoing innovation in this dynamic field. Ultimately, the fusion of EEG sensors, processing units, and user interfaces in BCIs heralds a new era of inclusivity and empowerment, where individuals previously marginalized by physical limitations find newfound avenues for expression, interaction, and independence. This transformative technology not only unlocks communication but also holds the key to reshaping our understanding of the human brain and its intricate workings, promising a f uture where disabilities no longer confine one's ability to engage with the world.

Role of corneal sensory nerves in tearing and blinking

The cornea is innervated trigeminal neurons classified in three different functional types: polymodal nociceptor, mechano‐nociceptor and cold thermoreceptor neurons. Corneal sensory nerves are responsible of the conscious sensations evoked by corneal stimulation, and are also involved in the trophic maintenance of the tissue. Besides, corneal nerve activity is also involved in the regulation of the protective functions of the ocular surface such as tearing and blinking.Regulation of reflex and basal tearing is integrated at the brainstem and, in both cases, under the influence of the sensory inflow provided by several types of corneal sensory nerves. While reflex tearing is induced selectively by the stimulation of corneal polymodal nociceptors, basal tearing rate depends on the spontaneous activity of cold thermoreceptors. Thus, when cold thermoreceptors are silenced by environmental warming, basal tearing is compromised.Voluntary, reflex and spontaneous (basal) blinking present differences in their characteristics and regulation mechanisms. Voluntary blinking depends on the direct instructions generated at the brain cortex, acting over the motor neurons located at the facial nucleus. Reflex blinking is integrated at the brainstem, being induced by the stimulation of the cornea and periocular skin, and even by loud sounds. Spontaneous blinking is claimed to be controlled by a CNS centre that established a blinking pattern. This pattern is modified under different conditions such as cognitive activity, being for example reduced during visual attentional tasks in order not to lose relevant visual information. When the activity of corneal cold thermoreceptors is abolished or reduced by ocular instillation of local anaesthetics, the frequency and characteristics of the spontaneous blinking is not modified. However, when the activity of cold thermoreceptors is increased for prolonged periods (for instance after topical instillation of F6H8 drops, which reduces the ocular surface temperature), blinking pattern become more regular and an increased number of blinks of larger the amplitude and shorter duration are induced. This increased blinking frequency produced when the activity of cold thermoreceptors is increased is sufficient to even counteract the reduction of blinking frequency induced during visual tasks performance. The increase in blink frequency driven by corneal cold thermoreceptors' activation may constitute a protective mechanism to prevent excessive desiccation of the ocular surface.(Supported by PID2020‐115934RB‐I00 from DOI: MCIN/AEI/10.13039/50110001103, and CIPROM/2021/48 from the Generalitat Valenciana, Spain)

Conscious sensations and protective reflexes driven by eye surface nerves in health and disease

The trigeminal primary sensory neurons that innervate the ocular surface, especially the cornea, have been classified in three functional types: polymodal nociceptors, mechano‐nociceptors and cold thermoreceptors. These sensory nerves are responsible for the conscious sensations evoked in response to ocular surface stimulation as well as for the regulation of tearing and blinking, and they are also involved in the trophic maintenance of the ocular tissues.Depending on the transducing channels they express in their membrane, sensory nerves from the ocular surface respond to different types of stimulus and, after this information is processed by the CNS, different conscious sensations are evoked: corneal mechano‐nociceptors' activation led to pricking pain; polymodal nociceptors evoke burning irritation, and cold thermoreceptors' activation may evoke freshness/cold/dryness/pain depending on the subtype of cold thermoreceptor neuron activated by the stimulus. While reflex blinking and tearing are driven by the activation of polymodal nociceptors as the afferent arm of the reflex, basal blinking and tearing rate are under the control of cold thermoreceptors' activity.During inflammation and after injury (such as UV‐induced keratitis, allergic keratoconjunctivitis, corneal surgery, tear‐deficient dry eye) the activity of corneal sensory nerves is modified in both eyes, even when inflammation or damage affects only one eye. The abnormal corneal sensory nerve activity constitutes the basis for the discomfort, dryness and pain sensations experienced under these conditions. Also, protective mechanisms depending on ocular nerve activity such as blinking and tearing become altered.(Supported by PID2020‐115934RB‐I00 from DOI: MCIN/AEI/10.13039/50110001103, and CIPROM/2021/48 from the Generalitat Valenciana, Spain)

Comparison of two different doses of xylazine and ketamine versus medetomidine for partial intravenous anaesthesia in horses

Thirty horses were randomly divided into three groups and sedated with xylazine (1.1 mg/kg). General anaesthesia was induced with diazepam (0.03 mg/kg) and ketamine (2.5 mg/kg). Partial intravenous anaesthesia was maintained with isoflurane and constant rate infusion (CRI) consisting of xylazine 0.33 mg/kg/h and ketamine 1.5 mg/kg/h (X+K); or, higher dose of xylazine 1.2 mg/kg/h and ketamine 3.6 mg/kg/h (XX+KK); or, medetomidine 3.5 μg/kg/h (MED). Horses in each group breathed spontaneously. Heart rate, respiratory rate, peripheral oxygen saturation, palpebral and corneal reflexes, rescue doses with ketamine, invasive arterial blood pressure, inspired and expired gas compositions were measured. Anaesthesia, surgery, and recoveries were timed, and recovery was scored. The xylazine with ketamine groups showed a higher respiratory rate, a significant decrease in consumption of isoflurane, and a shorter time to standing in comparison with the medetomidine group. Recovery of the lowest quality was observed in group MED and a significantly improved recovery was observed in group X+K. The CRI consisting of xylazine with ketamine was shown to be a suitable alternative to CRI with medetomidine in horses undergoing arthroscopy.

The Effects of Social Presence on Gaze, Movement, Arousal and Blink Rate in Autism: A Cooperative Virtual Reality Game-Based Approach

The Effects of Social Presence on Gaze, Movement, Arousal and Blink Rate in Autism: A Cooperative Virtual Reality Game-Based Approach

DriveAlert: Improving Road Safety with Real-time Monitoring of Driver Drowsiness through Blink Rate

DriveAlert: Improving Road Safety with Real-time Monitoring of Driver Drowsiness through Blink Rate

The Anesthetic Effect of Oral Administration of α-Chloroaldose and Dexmedetomidine on Silver Fox

In the past, anesthesia was delivered to foxes mostly through intramuscular or subcutaneous injection, which caused substantial stress to the animals, making it necessary to restrain them physically before the procedure. Moreover, research on anesthesia technology for domestic animals has been insufficient. Therefore, in this study, the α-chloroaldose and dexmedetomidine combination was used via oral administration to anesthetize foxes. Ten healthy silver foxes were administered the combination of oral anesthesia, and routine physiological indicators, anesthesia time and effects, and biological reflexes were continuously monitored. The temperature of anesthetized foxes after the administration of oral anesthesia continued to decrease, and by the end of the monitoring, it decreased by 1.3°C.The average SpO2 was 95.3 ± 2.2% during the whole anesthesia period. Changes in the heart rate were significant, initially showing a decreasing trend and then an increasing trend. The anesthesia period showed characteristics of smooth induction, proper maintenance, and rapid recovery. The sedative, analgesic, and muscle relaxant effects were more balanced and provided a good anesthesia effect time of 30 min: corneal, eyelid, and anal biological reflexes persisted and were inhibited at 20~50 min after oral medication, which shows a suitable depth of anesthesia.

Short-latency prepulse inhibition of the trigeminal blink reflex.

Prepulse inhibition (PPI) is a well-established phenomenon wherein a weak sensory stimulus attenuates the startle reflex triggered by a subsequent strong stimulus. Within the circuit, variations in target responses observed for PPI paradigms represent prepulse-induced excitability changes. However, little is known about the mechanism of PPI. Here, we focused on short-latency PPI of the trigeminal blink reflex R1 signal with an oligosynaptic reflex arc through the principal sensory trigeminal nucleus and the facial nucleus. As the facial nucleus is facilitatory to any input, R1 PPI is the phenomenon in the former nucleus. Considering that GABAergic modulation may be involved in PPI, this study investigated whether the PPI mechanism includes GABA-A equivalent inhibition, which peaks at approximately 30 ms in humans. In 12 healthy volunteers, the reflex was elicited by electrical stimulation of the supraorbital nerve, and recorded at the ipsilateral lower eyelid by accelerometer. Stimulus intensity was 1.5 times the R1 threshold for test stimulus and 0.9 times for the prepulse. The prepulse-test interval (PTI) was 5-150 ms. Results showed significant inhibition at 40-and 80-150-ms PTIs but not at 20-, 30-, 50-, 60-, and 70-ms PTIs, yielding two distinct inhibitions of different time scales. This corresponds well to the early and late components of inhibitory post synaptic potentials by GABA-A and GABA-B receptor activation. Thus, the data support the contribution of inhibitory post synaptic potentials elicited by the prepulse to the observed PPI. As inhibitory function-related diseases may impair the different inhibition components to varying degrees, methods deconvoluting each inhibitory component contribution are of clinical importance.

Facial Onset Sensory and Motor Neuronopathy with Neurotrophic Keratitis: A Case Report

Facial-onset sensory and motor neuronopathy (FOSMN) is a rare, progressive neurodegenerative disorder characterized by sensory loss and motor deficits, primarily affecting the face and upper extremities. The condition begins with sensory impairments in the trigeminal nerve distribution, extending to involve the scalp, neck, upper limbs, and trunk. Symptoms include facial weakness, bulbar disturbances (dysphonia, dysarthria, dysphagia, and sialorrhea), and lower motor neuron signs (weakness, atrophy, fasciculation, and cramps) in the limbs. A hallmark of FOSMN is the diminished or absent corneal reflex, indicating trigeminal nerve involvement and leading to potential complications like neurotrophic keratitis (NK), which can cause corneal ulceration and blindness. The etiology of FOSMN remains uncertain, with theories proposing autoimmune or neurodegenerative origins. Diagnosis is challenging due to the overlap with other ocular surface disorders, necessitating careful examination and differential diagnosis. Management focuses on symptomatic relief, including eye protection to prevent corneal complications. Awareness and early detection of ocular symptoms in FOSMN are crucial for preventing severe outcomes like NK and blindness.

Конъюнктивальный компонент компьютерного зрительного синдрома — причины и механизмы субъективных проявлений

Aim: to evaluate the frequency and severity of subjective conjunctival signs of computer vision syndrome (CVS) and to discuss their possible causes and mechanisms. Patients and Methods: online screening of 367 students from different Russian universities, including 303 (82.5%) girls and 64 (17.5%) boys, aged 15–30 years (20.6±0.1 years), was conducted using a multidimensional author's questionnaire and validated scales for assessing Internet addiction and daily duration and experience of using digital devices (DDs). Results: analysis of the screening data showed that only 10.3% of the respondents had no complaints of conjunctival signs of CVS. Predominant conjunctival symptoms (both in terms of frequency and severity) were dryness, redness and tearing. The structure of "always" and "very often" complaints of eye dryness (4.6% and 8.5% respectively), eye redness (3.3% and 7.0% respectively) and tearing (2.7% and 5.5% respectively) is similar. The structure of "very often" complaints differs from the structure of "always" complaints in that burning and itching (19.5%) ranks third after dryness (21.3%) and redness (20.4%). Eye dryness (5.2%), redness (4.0%) and tearing (2.7%) were the most common "very severe" complaints. Eye redness (10.3%), eye dryness (9.4%), and burning and itching (7.3%) were most common among "severe" complaints. Conclusion: the authors' findings and published data show that the high rate of complaints of visual discomfort with conjunctival signs and disorders of the lacrimal apparatus when using DDs is not only due to the effect of reduced blink rate and increased evaporation of the tear film, but also to much more complex, systemic neuro-ophthalmological mechanisms. The most likely mechanism is vegetative dysregulation resulting from excessive and prolonged use of information technologies and DDs, and ignorance of hygienic and ergonomic standards. KEYWORDS: computer vision syndrome, dry eye disease, conjunctivitis, neuro-ophthalmology, autonomic dysregulation. FOR CITATION: Akhmadeev R.R., Mukhamadeev T.R., Shaykhutdinova E.F., Khusniyarova A.R. Conjunctival component of computer vision syndrome — causes and mechanisms of subjective manifestations. Russian Journal of Clinical Ophthalmology. 2024;24(1):2–6 (in Russ.). DOI: 10.32364/2311-7729-2024-24-1-1.