- Association between tear film break up time and blink interval in visual display terminal users. [Journal Article]
- IJInt J Ophthalmol 2018; 11(10):1691-1697
- CONCLUSIONS: Subjects with shorter TBUT than blinking interval are prevalent among VDT users. Subjects over the age of 40 shows an increased risk for unstable tear film.
- Assessing the relationship between non-invasive tear break-up time and maximum blink interval values among young adults at Mzuzu University. [Journal Article]
- COClin Optom (Auckl) 2018; 10:87-91
- CONCLUSIONS: There is a positive significant correlation (r=0.64, r2=0.418, P<0.001) between NITBUT and MBI values. There was no significant difference between the NITBUT and MBI values between males and females. The study has also discovered that there is no correlation between NITBUT and MBI with age and gender.
- Changes in membrane properties of rat deep cerebellar nuclear projection neurons during acquisition of eyeblink conditioning. [Journal Article]
- PNProc Natl Acad Sci U S A 2018 10 02; 115(40):E9419-E9428
- Previous studies have shown changes in membrane properties of neurons in rat deep cerebellar nuclei (DCN) as a function of development, but due to technical difficulties in obtaining viable DCN slice...
Previous studies have shown changes in membrane properties of neurons in rat deep cerebellar nuclei (DCN) as a function of development, but due to technical difficulties in obtaining viable DCN slices from adult animals, it remains unclear whether there are learning-related alterations in the membrane properties of DCN neurons in adult rats. This study was designed to record from identified DCN cells in cerebellar slices from postnatal day 25-26 (P25-26) rats that had a relatively mature sensory nervous system and were able to acquire learning as a result of tone-shock eyeblink conditioning (EBC) and to document resulting changes in electrophysiological properties. After electromyographic electrode implantation at P21 and inoculation with a fluorescent pseudorabies virus (PRV-152) at P22-23, rats received either four sessions of paired delay EBC or unpaired stimulus presentations with a tone conditioned stimulus and a shock unconditioned stimulus or sat in the training chamber without stimulus presentations. Compared with rats given unpaired stimuli or no stimulus presentations, rats given paired EBC showed an increase in conditioned responses across sessions. Whole-cell recordings of both fluorescent and nonfluorescent DCN projection neurons showed that delay EBC induced significant changes in membrane properties of evoked DCN action potentials including a reduced after-hyperpolarization amplitude and shortened latency. Similar findings were obtained in hyperpolarization-induced rebound spikes of DCN neurons. In sum, delay EBC produced significant changes in the membrane properties of juvenile rat DCN projection neurons. These learning-specific changes in DCN excitability have not previously been reported in any species or task.
- StatPearls [BOOK]
- BOOKStatPearls Publishing: Treasure Island (FL)
- Complex partial seizures refer to focal seizures that start in one hemisphere of the brain and are associated with impairment in consciousness. Complex partial seizures are now preferably called as "...
Complex partial seizures refer to focal seizures that start in one hemisphere of the brain and are associated with impairment in consciousness. Complex partial seizures are now preferably called as "focal impaired awareness seizure" or "focal onset impaired awareness seizure." International League Against Epilepsy (ILAE) 2017 classification has categorized seizures based on three key features: the location of seizure onset, level of awareness during a seizure, and other features of seizures. Focal seizures refer to epileptiform activity starting in one area on one side of the brain. If awareness is impaired or affected at any time during the seizure, it is called focal impaired awareness seizure. Focal seizures are further classified into motor onset (automatisms, atonic, clonic, myoclonic, tonic, epileptic spasms, hyperkinetic) and nonmotor onset (autonomic, emotional, sensory, cognitive, behavior arrest) types. A seizure that starts on one side or one part of the brain and then spreads to both sides, earlier referred to secondarily generalized seizures, is now preferably termed as "focal to bilateral seizure." Focal seizures with impaired consciousness can present with or without an aura. Auras can last from a few seconds to as long as 1 to 2 minutes before the consciousness is impaired. Consciousness is maximally impaired in the beginning typically. Most of the seizures with automatisms last longer than 30 seconds, up to 1 to 2 minutes and sometimes can be as long as 10 minutes. Absence seizures can sometimes present with same symptomatology however ictal EEG will show generalized 3-Hz spike-wave complexes. Symptoms of focal seizures with impaired awareness depend on the area of the brain it is arising from. Most of the complex partial seizures arise from the temporal lobe. Extratemporal origin has been reported in at least 10% to 30% of patients. Seizures of Temporal Lobe Origin These are the most common type of focal impaired awareness seizures. Stereotyped automatisms occur in about 40% to 80% of patients with temporal lobe epilepsies. Seizures with predominantly oral and manual automatisms in addition to some other motor manifestations are highly suggestive of temporal lobe origin. About 60% of temporal lobe seizures have a secondary generalization. Gradual recovery after several minutes of confusion occurs postictally in most patients, however, in some patients automatic behavior like running, walking about, the nondirected violent behavior may occur. Temporal lobe focal impaired seizures can have features similar to frontal seizures, but temporal lobe focal impaired seizures typically have slower onset and progression, and more pronounced confusion. Certain features can help in localizing the seizure onset to one hemisphere. Ictal vomiting, ictal speech, urinary urge, and automatisms with intact consciousness suggest seizure onset in the non-dominant hemisphere, and speech disturbance postictally is suggestive of seizure onset in the dominant hemisphere. Upper limb dystonia lateralizes seizure to the opposite hemisphere. In young children with focal seizures of temporal lobe onset, behavioral arrest and unresponsiveness are common. Oroalimentary automatisms tend to occur in children older than age 5. In younger children, symmetric motor movement of the limbs and head nodding is typical. In infants, these seizures may be subtle with few automatisms. In very young infants, central apnea can occur. Temporal focal impaired seizures can be confused with absence seizures as both may have automatisms, but temporal seizures are usually longer in duration and are associated with postictal confusion. Seizures arising from mesial temporal lobe are characterized by auras such as epigastric sensation, deja vu, a feeling of fear, and unpleasant smells. Autonomic features like tachycardia, flushing, and pallor are common. Auras may be followed by impaired awareness and manual and oroalimentary automatisms. Automatisms in the upper limb and /or pupillary dilatation unilaterally may lateralize seizure to the ipsilateral hemisphere. Dystonia in the upper limbs and head and eye version on the opposite side can occur. Lateral temporal seizures may have vertigo, auditory (buzzing, ringing), or visual symptoms as initial aura symptoms. Auditory aura in only one ear may lateralize seizure to contralateral hemisphere. Initial aura is usually not prolonged, and impaired awareness is an early feature. Seizures are of shorter duration and progression to bilateral convulsions is more common than those arising from mesial temporal lobe. Seizures of Frontal Lobe Origin Up to 30% of the patients with focal epilepsy have seizures arising from the frontal lobe. It is the most common extratemporal type. Seizures are accompanied by loss of consciousness in about half of the patients with frontal lobe epilepsy. Focal impaired awareness seizures can arise from various locations within the frontal lobe, except the rolandic strip. These seizures typically are brief, lasting about 30 seconds, occurring in clusters, multiple times a day, are often nocturnal occurring during sleep and have minimal postictal confusion. Motor symptoms are predominant and range from hypermotor thrashing episodes like pelvic thrusting, bicycling movements to asymmetric tonic posturing. Sexual automatisms, bizarre behavior, and vocalizations are common. These seizures often have a stereotypical pattern for each patient. Nocturnal frontal lobe seizures may be mistaken for parasomnias. The ictal EEG may be difficult to interpret because of movement artifacts. Identification based on semiology alone and differentiating from mesial temporal lobe epilepsy may be difficult, however earliest signs and symptoms and their order of appearance may help in distinction. Seizures with hypermotor features are more likely to have ictal focus in the orbitofrontal and frontopolar regions. Temporal lobe seizures have more oroalimentary automatisms, gesturing and fumbling semiology. Epileptiform activity in frontal convexity can cause clonic seizures, and in the supplementary motor area can cause tonic seizures. Unique semiology of supplementary sensorimotor cortex includes deviation of head and eye to the side contralateral to seizure onset, the asymmetrical posturing of upper limbs with an extension of arm contralateral to the side of seizure onset and flexion of ipsilateral arm. Orbitofrontal region seizures are automotor type and manifest prominently with autonomic phenomena like flushing, vocalization, and automatisms. Anterior cingulate gyrus seizures have predominant motor manifestations like hypermotor seizures and complex motor seizures. Posterior cingulate cortex epilepsies predominantly have altered consciousness and automotor seizures as main clinical manifestations. Antero-lateral dorsal convexity seizures may manifest with auras such as dizziness, epigastric sensation, behavioral arrest and speech arrest. Seizures of Parietal Lobe Region Seizures arising from parietal lobe may be difficult to diagnose because of their subjective nature. Positive and /or negative sensory features are common. Sensorimotor phenomenon and vestibular hallucinations suggest onset in the parietal lobe. Paresthesias, visual hallucinations, visual illusions, somatic illusions, vertiginous features can occur. Seizures arising from the dominant hemisphere can cause receptive language impairment. Parietal lobe complex partial seizures can have auras like epigastric sensations, visual hallucinations, panic attacks and behavioral arrest. Often there is involvement of other lobes as the seizure spreads. When focal seizures from parietal lobe spread and involve the temporal lobe, loss of consciousness and automatisms may occur. Seizures of occipital lobe origin Seizures with ictal origin in the occipital lobe are characterized by a visual aura and are difficult to diagnose especially in young children. Visual auras, typically of elementary sensations, ictal blindness, versions of the head and eyes to opposite side, rapid and forced blinking, oculoclonic activity are some features suggesting occipital lobe as an origin of focal seizure with impaired consciousness. Seizures from primary visual cortex can cause bilateral loss of vision in the form of white-out or black-out. Shorter duration of visual aura (less than 2 minutes) can help to differentiate from migraine aura which is typically longer (5 to 15 minutes). Complex, formed visual hallucinations like pictures of people, animals, etc. are associated with seizure onset in the extra-striate cortex. Other symptoms may result from spread to temporal or parietal lobes. Seizures of Insular Lobe Origin Seizures arising from the insula can mimic frontal, temporal, parietal lobe seizures. Origin from the insula is suspected when viscerosensitive symptoms (nausea, vomiting, salivation), motor symptoms (tonic, hypermotor or generalized tonic-clonic movements), and/or sensory symptoms (numbness, tightness, vibration, pain, vertigo) occur at seizure onset.
- Blink patterns and kinematics of eyelid motion in ophthalmologically normal horses. [Journal Article]
- AJAm J Vet Res 2018; 79(6):650-657
- CONCLUSIONS: AND CLINICAL RELEVANCE Kinematic variables of ophthalmologically normal horses were similar to values reported for humans. Horses had a greater percentage of complete squeeze blinks, which could increase tear film stability. Blinking kinematics can be assessed as potential causes of idiopathic keratopathies in horses.
- Simultaneous Subconjunctival Triamcinolone and Bevacizumab Injections for Management of Blepharokeratoconjunctivitis in Children. [Journal Article]
- CRCase Rep Ophthalmol Med 2018; 2018:2602487
- CONCLUSIONS: This case series highlights the potential vision threatening complications of BKC. In addition to conventional management options, this report is the first published use of subconjunctival triamcinolone and bevacizumab injections for BKC in children in an attempt to minimize and improve corneal neovascularization and scarring and subsequently to retain useful vision.
- [Influence of blue light from visual display terminals on human ocular surface]. [Journal Article]
- ZYZhonghua Yan Ke Za Zhi 2018 Jun 11; 54(6):426-431
- Objective: To investigate the influence of blue light from visual display terminals (VDTs) on human ocular surface. Methods: Prospective intervention test Thirty volunteers were recruited to watch ...
Objective: To investigate the influence of blue light from visual display terminals (VDTs) on human ocular surface. Methods: Prospective intervention test Thirty volunteers were recruited to watch videos on the same VDT in a dark environment, about 40 cm from the screen. Volunteers were supposed to watch videos in the night shift mode that reduces the amount of blue light for 1 hour. At the same time of the second day, they watched the same videos on the VDT in the normal mode for 1 hour. Tear film break-up time (BUT), corneal fluorescein staining scores, lipid layer thickness (LLT), times of blinking in 19.1 seconds and the ratio of partial blinking in 19.1 seconds were measured before and after each watching. Meanwhile, volunteers were asked to complete a questionnaire about their subjective experience after watching. Results: BUT, corneal fluorescein staining scores and LLT showed no significant decreases in the volunteers after they watched videos on the VDT in the night shift mode [BUT before watching: (8.08±3.15)s, BUT after watching in the night shift mode: (5.31±2.49)s, t=-0.52, P>0.05], but there were significant decreases after they watched videos in the normal mode [BUT after watching in the normal mode: (3.35±1.95) s, t=2.40, P<0.05]. At the same time, there was a significant difference between night shift mode and normal mode[BUT after watching in the night shift mode (5.31±2.49)s, BUT after watching in the normal mode: (3.35±1.95)s, t=3.67, P<0.05). Times of blinking and the ratio of partial blinking in 19.1 seconds were increased modestly after watching in 2 different modes, but there was no significant difference(times of blinking after watching in the night shift mode were 5.55±3.27, times of blinking after watching in the normal mode were 5.93±3.59, t=-0.92, P>0.05). The questionnaire results showed that 70.0%(21) of the volunteers reported mild discomfort including eye dryness, itching, pain, foreign body sensation, redness and asthenopia, 46.7%(14) reported no difference between the 2 modes, 36.7%(11) preferred the night shift mode, 16.6%(5) felt better with the normal mode, and 80.0%(24) would like to try the night shift mode in their daily life. Conclusions: Use of VDTs for a short period of time can lower the stability of tear film. The night shift mode may cause less damage to the ocular surface than the normal mode. High-energy blue light from VDTs can be a risk factor in the ocular surface damage, but the damage is reversible. (Chin J Ophthalmol, 2018, 54: 426-431).
- Reorganization of sensorimotor gating after peripheral facial palsy starts at brainstem. [Journal Article]
- NRNeurol Res 2018; 40(7):541-548
- Background and objective We aimed to analyze the alterations in sensorimotor gating at brainstem after peripheral facial palsy (PFP). To examine sensorimotor gating, we used prepulse modulation (PPM)...
Background and objective We aimed to analyze the alterations in sensorimotor gating at brainstem after peripheral facial palsy (PFP). To examine sensorimotor gating, we used prepulse modulation (PPM) of blink reflex (BR). We also recorded BR recovery to identify excitability changes in the facial nucleus. Patients and method We included 33 patients and 39 recordings. Control group was composed of 16 healthy subjects. Simultaneous bilateral baseline BR, BR recovery at ISI of 300-ms and BR-PPM at ISI of 100-ms recordings were performed after stimulation of trigeminal nerve on right sides of healthy subjects and on both sides of patients. Severity of PFP and time lapse from the onset was noted. Results Mean R1 amplitude was increased, whereas mean R2 and R2c magnitude were reduced in all groups after prepulse stimulation. However, multivariate ANOVA showed significance at group level (patients and healthy subjects), at prepulse level (no prepulse and 100-ms prepulse) and group and prepulse level. Suppression of R2 or R2c was lower on both sides of patients compared to healthy subjects and the deficit first started on the symptomatic side. Conclusion Suppression of R2 and R2c after prepulse stimulation is reduced in PFP suggesting decreased filtering of facial sensory input at brainstem level. Trigeminal sensitization at brainstem develops early after PFP.
- [Magnetic resonance imaging features of tear outflow and structural changes of the lacrimal sac and nasolacrimal duct in normal subjects with eyes closed]. [Journal Article]
- ZYZhonghua Yan Ke Za Zhi 2018 Mar 11; 54(3):205-211
- Objective: To investigate the static and dynamic features of the normal lacrimal sac (LS)-nasolacrimal duct (NLD), and find out if tear flows while the subject is in supine position with eyes closed...
Objective: To investigate the static and dynamic features of the normal lacrimal sac (LS)-nasolacrimal duct (NLD), and find out if tear flows while the subject is in supine position with eyes closed. Methods: Cross-sectional study. Healthy volunteers and patients whose head were examined by MRI in Guangdong Provincial Hospital of Integrated Traditional Chinese and Western Medicine with normal LS-NLD were recruited. The normal lacrimal ducts of the candidates were scanned, while candidates remained in supine position, by static or dynamic imaging procedures with a 1.5T MRI system, which adopted the thinnest slice thickness, consecutive sections (no spacing) and two scanning planes (axial and coronal planes of LS-NLD). The static and dynamic imaging procedures were done in June and July 2014 and October 2015, respectively. The static imaging was performed with conventional T(2)WI, contrast-enhanced 3D FIESTA-C, contrast-enhanced T(1)WI and heavy T(2)WI pulse sequences under normal physiological condition, and 104 eyes with normal LS-NLD from 39 patients and 13 healthy volunteers (21 male and 31 female) aged 10 to 75 years were scanned with the static procedure. The dynamic imaging was done with heavy T(2)WI pulse sequence. The coronal dynamic imaging was done only after 0.9% NaCl was instilled in the conjunctival sacs, and 20 eyes with normal LS-NLD of 10 volunteers (6 male and 4 female) aged 23 to 53 years were scanned with the coronal dynamic procedure. The axial dynamic imaging was done under normal physiological condition and after 0.9% NaCl was instilled in the conjunctival sacs respectively, and 20 eyes with normal LS-NLD of 10 volunteers (8 male and 2 female) aged 20 to 40 years were scanned with the axial dynamic procedure. The incidences on the axial dynamic imaging under the two conditions were compared with χ(2) test. Results: A total of 104 eyes with normal LS-NLD (52 candidates) were scanned with the static imaging sequences. In all LS-NLDs, an indentation located at the posterior-lateral side wall of the junction of LS-NLD was discovered, and its depth was variable. In 28.8% (30/104) of LS, 64.4% (67/104) of the junctions and 22.1% (23/104) of NLD, lumens were closed. As for the coronal dynamic imaging (20 eyes with normal LS-NLD in 10 subjects), segmental tear transit was observed in 15/20 of NLD. As for the axial dynamic imaging (20 eyes with normal LS-NLD in 10 subjects), after 0.9% NaCl was instilled, dynamic changing of their lumen size was revealed in 17/20 of LS-NL and the occurrence rate of the lumen size changing (29.3%, 94/321, the number of the axial slices with lumen changes/total number of the axial slices imaged) was higher than that (16.4%,52/317) under normal physiological condition. The difference between the two rates was statistically significant (χ(2)=14.993, P<0.001). LS contained more tear than NLD. Conclusion: While the candidates are in supine position with eyes closed (absolutely no blinking), an indentation is at the posterior-lateral side wall of the junction of LS-NLD, and there are autonomous, segmental lumen open-close actions in normal LS-NLD and tear transit in their lumens. (Chin J Ophthalmol, 2018, 54: 205-211).
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- Sensitivity of Diagnostic Tests for Dry Eye in Patients with Blepharospasm. [Journal Article]
- ACActa Clin Croat 2017; 56(3):375-381
- The aim of the study was to evaluate diagnostic tests for keratoconjunctivitis sicca (Schirmer test, tear break-up time (TBUT) test, and corneal staining with fluorescein and lissamine green dye) in ...
The aim of the study was to evaluate diagnostic tests for keratoconjunctivitis sicca (Schirmer test, tear break-up time (TBUT) test, and corneal staining with fluorescein and lissamine green dye) in patients with blepharospasm. This prospective study included 60 female patients older than 40 with blepharospasm, divided into two groups according to clinical symptoms. For fluorescein test, the surface under the ROC curve was 1.0 with standard error (SE) 0 and 95% confidence interval (95% CI) 0.940-1.0; for Schirmer test, the surface under the ROC curve was 0.817 with SE 0.0555 and 95% CI 0.696-0.905; for lissamine green test, the surface under the ROC curve was 0.813 with SE 0.056 and 95% CI 0.691-0.902; and for TBUT test, the surface under the ROC curve was 0.772 with SE 0.061 and 95% CI 0.645-0.870. According to the results of ROC curve, which determines the sensitivity and specificity of normal values, comparison of diagnostic tests for keratoconjunctivitis sicca used in this study showed that fluorescein test had the best sensitivity and specificity. Schirmer test should be avoided in patients with blepharospasm because its results are influenced by frequent blinking and are not appropriate for study interpretation. Despite the pathologic values of TBUT test (numerically), this test is still acceptable for patients with blepharospasm because its interval takes more time than the interval between two blinks.