Antiseizure Medication-Induced Nystagmus During Eye Closure Identified by Electroencephalography.

Nystagmus is a well-known side effect of antiseizure medicines (ASMs), but it is often underestimated and overlooked. Here, we describe a case in which nystagmus during eye closure was identified early using routine electroencephalography (EEG). A 34-year-old man developed focal epilepsy after head trauma at the age of 25 years. The patient was treated with carbamazepine but liver dysfunction was observed; therefore, treatment was attempted with lacosamide (LCM) and lamotrigine. With an increase in the LCM dose, steep potential changes suggestive of horizontal nystagmus were observed in the electrooculogram, F7, and F8 on EEG, and the patient complained of eye shaking during eye closure. These symptoms and EEG findings improved with LCM dose reduction. If the presence of nystagmus is identified on EEG coincidentally and a patient's subjective symptoms with ASM are confirmed, it is advisable to taper and/or discontinue the causative agent.

Intraoperative motor-evoked potential with tetanic stimulation changes pre- and post-hemispherotomy.

BACKGROUND: Careful examination of motor-evoked potential (MEP) findings is critical to the safety of intraoperative neuromonitoring during neurosurgery. We reviewed the intraoperative MEP findings in a pediatric patient who had undergone hemispherotomy for refractory epilepsy. CASE DESCRIPTION: The patient was a 4-year-and-2-month-old boy with extensive right cerebral hemisphere, drug-resistant epilepsy, left upper and lower extremity paralysis, and cognitive impairment. We examined intraoperative MEP results both before and after hemispherotomy. Post-hemispherotomy and MEPs were successfully elicited through transcranial electrical stimulation (TES) but not via direct cortical stimulation on the right side. Furthermore, TES on the right side, following hemispherotomy, led to a reduction in the MEP amplification effect resulting from tetanic stimulation of the left unilateral median and tibial nerves. Conversely, we observed the effects of MEP amplification during TES on the left side after tetanic stimulation of these nerves. Postoperatively, the patient underwent magnetic resonance imaging and electroencephalogram examinations, confirming the anatomical and electrophysiological completeness of the dissection. Notably, the seizures disappeared, and no apparent complications were observed. CONCLUSION: Collectively, our findings suggest that TES can still activate deep structures and elicit MEPs, even in cases where the corticospinal connections to the posterior limb of the internal capsule are entirely severed. Thalamo-cortical interactions may affect the MEP amplification, observed during tetanic stimulation. Injury to the corticospinal tracts of the white matter may be obscured on conventional MEP findings; however, it may be identified by MEP changes in tetanic stimulation.

Effect of Sevoflurane Anesthesia on Intraoperative Spikes, High-Frequency Oscillations, and Phase-Amplitude Coupling in MRI-Normal Hippocampus.

INTRODUCTION: The purpose of this study was to determine the effect of sevoflurane anesthesia on spikes, high-frequency oscillations (HFOs), and phase-amplitude coupling using a modulation index in MRI-normal hippocampus, with the aim of evaluating the utility of intraoperative electrocorticography in identifying the epileptogenic hippocampus during sevoflurane administration. METHODS: Eleven patients with intractable temporal lobe epilepsy with a normal hippocampus on MRI underwent extra-operative electrocorticography evaluation. Patients were assigned to the Ictal (+) or Ictal (-) group depending on whether the parahippocampal gyrus was included in the seizure onset zone. Intraoperative electrocorticography was performed under 0.5 and 1.5 minimum alveolar concentration of sevoflurane. The rates of spikes, ripples, fast ripples (FRs), ripples on spikes, FRs on spikes, and MI HFO(3-4 Hz) were evaluated. RESULTS: During the intraoperative electrocorticography procedure, sevoflurane administration was found to significantly increase the rate of spikes, ripples on spikes, fast ripples on spikes, and MI HFO(3-4 Hz) in the Ictal (+) group (P < 0.01). By contrast, the Ictal (-) group exhibited a paradoxical increase in the rate of ripples and fast ripple (P < 0.05). CONCLUSIONS: Our findings indicate that the administration of sevoflurane during intraoperative electrocorticography in patients with MRI-normal hippocampus can lead to a dose-dependent enhancement of epileptic biomarkers (spikes, ripples on spikes, fast ripples on spikes, and MI (HFO 3-4)) in the epileptogenic hippocampus, while paradoxically increasing the rate of ripples and fast ripple in the nonepileptogenic hippocampus. These results have significant implications for the identification of the MRI-normal hippocampus that requires surgical intervention and preservation of the nonepileptogenic hippocampus.

Abnormal magnetic resonance imaging signal in the burr hole and the identification of the intracranial infection of a deep brain stimulation device: illustrative case.

BACKGROUND: Device infection is a critical postoperative complication in deep brain stimulation (DBS). However, intracranial infections are rare and lack specific findings, which lead to a challenging diagnosis. OBSERVATIONS: A 59-year-old female with generalized dystonia underwent bilateral globus pallidus internus and subthalamic nucleus (STN) DBS device implantation. One year earlier, a left STN-DBS extension wire disconnection was observed and replaced. The patient presented to our department because of tenderness along the extension wire that had persisted for 1 month. Magnetic resonance imaging (MRI) of the head indicated abnormal signals around the lead of the left STN and burr hole. Intraoperatively, the authors observed pus and infected granulation tissue in the burr holes. After device removal, antibiotics were administered, and the patient successfully progressed without complications. Moreover, the abnormal MRI signal disappeared. LESSONS: A characteristic abnormal MRI signal within the burr hole in DBS may suggest early infection even in the absence of other inflammatory findings. Clinicians should ensure that MRI is not limited to intracranial findings but extends beyond the extracranial space.

Mid-infrared photoacoustic spectroscopy based on ultrasound detection for blood component analysis.

For the non-invasive measurement of biological tissue, a piezoelectric photoacoustic spectroscopy (PZT-PAS) system that detects a single frequency of ultrasound induced by the irradiation of pulse-modulated mid-infrared laser light was developed. PA spectra of the optical phantom and biological samples were obtained, and the relationship between the PA signal intensity and optical absorbance in the fingerprint region (930-1,200 cm-1) was analyzed to estimate the optical absorbance. The resonance vibration of the induced ultrasound was utilized to further increase the signal strength for biological tissue measurement. Consequently, PA spectrum reflecting the absorption of components in biological tissues was obtained.

Generalized Epilepsy With Repetitive Sinus Pauses Following Generalized Tonic-Clonic Seizures Due to Reduced Baroreflex Sensitivity.

Epilepsy and syncope are sometimes difficult to differentiate, and they often occur together. We report here a unique case of severe neuromodulatory syncope associated with generalized epilepsy. A 24-year-old right-handed female with no remarkable history had her first epileptic seizure when she was 15 years old and was diagnosed with epilepsy. However, she had epileptic seizures or fainting spells every few months and was referred to Nara Medical Center at the age of 23 years. No obvious neurological abnormality was present, and no organic abnormality was found on head magnetic resonance imaging. The seizures were symmetrical generalized tonic-clonic seizures (GTCS) without aura, and the patient was unable to stand up for several hours after the seizure. Long-term video electroencephalogram monitoring revealed two types of seizures: (1) GTCS starting with generalized polyspikes and waves and (2) fainting with sinus arrest for up to 10 seconds when the patient tried to stand up after GTCS. After the addition of valproic acid following the diagnosis of generalized epilepsy, her epileptic seizures improved, but syncope remained. We consulted the cardiology department of our hospital and diagnosed mixed neuromodulatory syncope after performing the tilt test. She underwent catheter ablation for cardioneuromodulation, and her syncope improved. Several reports have described reduced baroreflex sensitivity during the interictal period in epilepsy, and seizure-related autonomic dysfunction has been implicated in sudden unexpected death in epilepsy (SUDEP). In addition to suppression of epileptic seizures, when autonomic nervous system symptoms associated with epilepsy are severe, as in this case, a thorough cardiovascular examination should be performed, and the patient should be treated with the goal of preventing SUDEP.

Additional Effect of High-output Current and/or High-duty Cycle in Vagus Nerve Stimulation for Adolescent/Adult Intractable Epilepsy.

A vagus nerve stimulation (VNS) device delivers electrical pulses to the vagus nerve at a rhythm defined by the duty cycle. The standard therapeutic range is advocated for an output current of 1.5-2.25 mA and a duty cycle of 10%. As the optimal settings vary from patient to patient, some patients may benefit from additional seizure reduction when stimulated beyond the standard range. A total of 74 patients (15 children aged <12 years and 59 adolescents/adults) who underwent VNS implantation between 2011 and 2020 and who were followed up for at least 2 years were included in this retrospective study. Stimulation parameters exceeding 2.25 mA of output current, 25% of duty cycle, and 0.5625 (2.25 mA × 25%) of current × duty cycle were defined as high stimulation. The proportion achieved an additional seizure reduction of 20%, and the 50% seizure reduction rate at the last follow-up was compared between adolescents/adults and children. Approximately 40% of patients in adolescents/adults treated with high stimulation experienced an additional acute effect, resulting in a 50% or greater reduction in seizures in almost all patients. Moreover, in adolescents/adults, 22.2%-41.9% of the patients were treated with high stimulation, and the responder rate was 69.5%. Conversely, the responder rate in children was 26.7%, significantly worse than that in adolescents/adults, despite higher stimulation. VNS with high-stimulation settings is effective for adolescent and adult patients with intractable epilepsy. Even high stimulation may not be effective in extremely refractory pediatric epilepsy with a high seizure frequency.

Motor-evoked potential monitoring from urinary sphincter muscle during pediatric untethering surgery: a case series.

PURPOSE: Postoperative urinary dysfunction following untethering surgery for spinal lipoma is devastating. To assess urinary function, we invented a pediatric urinary catheter equipped with electrodes for the direct transurethral recording of myogenic potential from the external urethral sphincter (EUS). This paper presents two cases in which urinary function was monitored intraoperatively by recording of motor-evoked potential (MEP) from EUS during untethering surgery in children. METHODS: Two children (aged 2 and 6 years) were included in this study. One patient had no preoperative neurological dysfunction, while the other had frequent urination and urinary incontinence. A pair of surface electrodes was attached to a silicone rubber urethral catheter (6 or 8 Fr; diameter, 2 or 2.6 mm). The MEP from the EUS was recorded to assess the function of the centrifugal tract from the motor cortex to the pudendal nerve. RESULTS: Baseline MEP waveforms from the EUS were successfully recorded with latency and amplitude of 39.5 ms and 66 µV in patient 1 and 39.0 ms and 113 µV in patient 2, respectively. A significant decrease in amplitude was not observed during surgery in the two cases. No new urinary dysfunction and complications associated with the urinary catheter-equipped electrodes developed postoperatively. CONCLUSION: Using an electrode-equipped urinary catheter, monitoring of MEP from the EUS could be applicable during untethering surgery in pediatric patients.

Left Temporal Pole Encephalocele With Independent Hippocampal Seizures: Surgical Strategy and Relevance of Epileptic Biomarkers.

SUMMARY: Temporal pole encephalocele (TE) is an increasingly recognized surgically treatable subtype of refractory temporal lobe epilepsy that rarely shows hippocampal involvement. A 27-year-old patient presented with medically intractable epilepsy because of a left temporal pole encephalocele with a normal hippocampus on MRI. Extraoperative electrocorticography showed independent seizure onset with distinct morphology of seizure onset pattern from the temporal pole encephalocele and hippocampus. Additional analysis of ictal and interictal fast ripples revealed different electrophysiological fast ripple profiles in the two seizure onset zones. The patient underwent temporopolar disconnection, eliminating the need for large dural repair and multiple hippocampal transections that helped preserve the intrahippocampal and extrahippocampal memory pathways. Herein, the authors report that independent hippocampal seizures can be observed in patients with temporal pole encephalocele. Features of the ictal and interictal fast ripples can differ depending on the morphology of the seizure onset pattern. The authors suggest that, the interpretation of fast ripples in clinical practice should take seizure onset patterns into consideration.

Effects of intraoperative motor evoked potential amplification following tetanic stimulation of the pudendal nerve in pediatric craniotomy.

OBJECTIVE: Monitoring the intraoperative motor evoked potentials (MEPs) in pediatric craniotomy is challenging because of its low detection rate, which makes it unreliable. Tetanic stimulation of the peripheral nerves of the extremities and pudendal nerves prior to transcranial electrical stimulation (TES) or direct cortical stimulation (DCS) amplifies the MEPs. The authors investigated the effects of MEP amplification following tetanic stimulation of the median and tibial nerve or the pudendal nerve in pediatric patients undergoing craniotomy. METHODS: This prospective observational study included 15 patients ≤ 15 years of age (mean age 8.9 ± 4.9 years) undergoing craniotomy. MEPs were obtained with TES (15 cases) or DCS (8 cases)-conventional MEP without tetanic stimulation (c-MEP) and MEP following tetanic stimulation of the unilateral median and tibial nerves (mt-MEP) or following tetanic stimulation of the pudendal nerve (p-MEP) were used. Compound muscle action potentials were elicited from the abductor pollicis brevis, gastrocnemius, tibialis anterior, and abductor hallucis longus muscles. The authors compared the identification rate and the rate of amplitude increase of each MEP. RESULTS: For both TES and DCS, the identification and amplitude increase rates were significantly higher in cases without preoperative hemiparesis for p-MEPs than in those for c-MEPs and mt-MEPs. In comparison to patients with preoperative hemiparesis, p-MEPs displayed a higher identification rate, with fewer false negatives in DCS cases. CONCLUSIONS: In pediatric craniotomy, the authors observed the amplification effect of MEPs with pudendal nerve tetanic stimulation and the amplification effect of DCS on MEPs without increasing false negatives. These findings suggested the likelihood of more reliable intraoperative MEP monitoring in pediatric cases.

Expansion of Substrate Scope for Nitroxyl Radical/Copper-Catalyzed Aerobic Oxidation of Primary Alcohols: A Guideline for Catalyst Selection.

Four distinctive sets of optimum nitroxyl radical/copper salt/additive catalyst combinations have been identified for accommodating the aerobic oxidation of various types of primary alcohols to their corresponding aldehydes. Interestingly, less nucleophilic catalysts exhibited higher catalytic activities for the oxidation of particular primary allylic and propargylic alcohols to give α,ß-unsaturated aldehydes that function as competent Michael acceptors. The optimum conditions identified herein were successful in the oxidation of various types of primary alcohols, including unprotected amino alcohols and divalent-sulfur-containing alcohols in good-to-high yields. Moreover, N-protected alaninol, an inefficient substrate in the nitroxyl radical/copper-catalyzed aerobic oxidation, was oxidized in good yield. On the basis of the optimization results, a guideline for catalyst selection has been established.

Isolation and Characterization of a Novel Jumbo Phage from Leaf Litter Compost and Its Suppressive Effect on Rice Seedling Rot Diseases.

Jumbo phages have DNA genomes larger than 200 kbp in large virions composed of an icosahedral head, tail, and other adsorption structures, and they are known to be abundant biological substances in nature. In this study, phages in leaf litter compost were screened for their potential to suppress rice seedling rot disease caused by the bacterium Burkholderia glumae, and a novel phage was identified in a filtrate-enriched suspension of leaf litter compost. The phage particles consisted of a rigid tailed icosahedral head and contained a DNA genome of 227,105 bp. The phage could lyse five strains of B. glumae and six strains of Burkholderia plantarii. The phage was named jumbo Burkholderia phage FLC6. Proteomic tree analysis revealed that phage FLC6 belongs to the same clade as two jumbo Ralstonia phages, namely RSF1 and RSL2, which are members of the genus Chiangmaivirus (family: Myoviridae; order: Caudovirales). Interestingly, FLC6 could also lyse two strains of Ralstonia pseudosolanacearum, the causal agent of bacterial wilt, suggesting that FLC6 has a broad host range that may make it especially advantageous as a bio-control agent for several bacterial diseases in economically important crops. The novel jumbo phage FLC6 may enable leaf litter compost to suppress several bacterial diseases and may itself be useful for controlling plant diseases in crop cultivation.

Cough syncope and hyperventilation-induced convulsion in Chiari 1.5 malformation.

Chiari malformation type I (CM1) is defined as cerebellar tonsillar herniation below the level of the foramen magnum. Syncope, especially cough syncope, is a rare but important symptom of CM1 patients. Here, we report a CM1 patient, in combination with brainstem herniation (CM1.5), presenting with repetitive syncope who was successfully treated by decompressive surgery. A 43-year-old right-handed male, with 5-year history of repeated episodes of loss of consciousness in association with cough, was investigated. Neurological examination revealed slight muscle weakness, clumsiness, and sensory disturbance in the left upper limb. There was no sign of orthostatic hypotension or orthostatic intolerance. Cranial and spinal magnetic resonance imaging revealed a herniation of the cerebellar tonsils and a syringomyelia. Forced hyperventilation during electroencephalogram (EEG) induced brief generalized symmetric clonic convulsions with preserved consciousness, but no overt EEG seizure patterns or slow activities were found. Based on the diagnosis of CM1.5 with recurrent episodes of loss of consciousness, he underwent foramen magnum decompression. He has no recurrence of the episode after the surgery on 1 year follow-up. Decompressive surgery was an effective procedure for cough syncope and other symptoms of the current patient with CM1.5. Dissociation of cerebrospinal fluid pressure between the cranial and spinal compartments which leads further herniation of the cerebellar tonsils and subsequent compression on the cerebellum and the brainstem is considered to be the major mechanism of his cough syncope. Analysis of EEG can be useful not only to diagnose epileptic seizures but also to elucidate mechanisms of syncope and concurrent involuntary movements.

Complete genomic sequence of a novel phytopathogenic Burkholderia phage isolated from fallen leaf compost.

In contrast to most Burkholderia species, which affect humans or animals, Burkholderia glumae is a bacterial pathogen of plants that causes panicle blight disease in rice seedlings, resulting in serious damage to rice cultivation. Attempts to combat this disease would benefit from research involving a phage known to attack this type of bacterium. Some Burkholderia phages have been isolated from soil or bacterial species in the order Burkholderiales, but so far there has been no report of a complete genome nucleotide sequence of a phage of B. glumae. In this study, a novel phage, FLC5, of the phytopathogen B. glumae was isolated from leaf compost, and its complete genome nucleotide sequence was determined. The genome consists of a 32,090-bp circular DNA element and exhibits a phylogenetic relationship to members of the genus Peduovirus, with closest similarity to B. multivorans phage KS14. In addition to B. glumae, FLC5 was also able to lyse B. plantarii, a pathogen causing rice bacterial damping-off disease. This is the first report of isolation of a P2-like phage from phytopathogenic Burkholderia, determination of its complete genomic sequence, and the finding of its potential to infect two Burkholderia species: B. glumae and B. plantarii.

[Elevation of cerebrospinal fluid anti-cyclic citrullinated peptides antibody index is useful for rheumatoid meningitis preceding neurological symptoms without arthritis: a case report].

We report a 62-year-old female with rheumatoid meningitis. She presented with mental disorder, loss of consciousness, generalized seizures, and cognitive impairment. Brain MRI demonstrated high intensity lesions and abnormal enhancement along the left frontal and parietal sulci. Her serum and cerebrospinal fluid were positive for anti-cyclic citrullinated peptides (CCP) antibody, and the antibody index of cerebrospinal fluid anti-CCP antibody increased, which led us to suspect rheumatoid meningitis. Her symptoms improved immediately by methylpredonisolone pulse therapy and anti-CCP antibody turned negative in cerebrospinal fluid. However, she revealed arthritis with the reduction of betamethasone and was diagnosed as rheumatoid arthritis. We suggest that the elevation of antibody index of cerebrospinal fluid anti-CCP antibody is useful in the diagnosis of rheumatoid meningitis preceding neurological symptoms without arthritis, and anti-CCP antibody in cerebrospinal fluid may be helpful as the evaluation of the treatment.

Deep slow nasal respiration with tight lip closure for immediate attenuation of severe tics.

BACKGROUND: Severe intractable tics, which are associated with Tourette syndrome and chronic tic disorder (TS/CTD), severely affect the quality of life. Common less-invasive treatments are often unable to attenuate tics with deep brain stimulation currently being the only effective treatment. We aimed to assess the anti-tic effect of deep slow nasal respiration with tight lip closure using patients with TS/CTD. METHODS: We retrospectively analyzed 10 consecutive patients (9 men, 1 woman; 23-41 years old). We instructed the patients to perform the procedure for 120 s and to obtain a video recording of before and during the procedure. The videos were used to count tics and determine lip competency or incompetency. The counted tics were rated using the modified Rush Video Rating Scale. RESULTS: Compared with before the procedure, there were significantly lower frequencies of motor and phonic tics, as well as video scored, during the procedure. Eight patients presented with lip incompetency before the procedure and none after the procedure (P = 0.041). There were no side effects associated with the procedure. CONCLUSION: Our findings indicate that deep slow nasal respiration with tight lip closure ameliorates tics in patients with TS/CTD. In accordance with our results, lip opening and oral breathing could be causes of tics, in addition to heritability. Therefore, this novel procedure could improve tics. Furthermore, our findings could contribute toward the development of tic treatments and elucidate their pathophysiology regarding the reward system, hypersensitivity, autonomic nerves, and nasal airway.