1.Initial absence of N20 waveforms from median nerve somatosensory evoked potentials in a patient with cardiac arrest and good outcomes
Miguel E HABEYCH ; Pouria MOSHAYEDI ; Jon C RITTENBERGER ; Scott R GUNN
Clinical and Experimental Emergency Medicine 2019;6(2):177-182
A 34-year-old male was brought to the hospital with a chest gunshot wound. Pulseless upon arrival, blood pressure was absent for 10 minutes. A thoracotomy resulted in return of spontaneous circulation. On hospital day 5, with brainstem reflexes present, he was unresponsive to call or pain, exhibited generalized hyperreflexia and bilateral Babinskys. Median nerve somatosensory evoked potentials (mSSEPs) and brainstem auditory evoked potentials were obtained. International Federation of Clinical Neurophysiology recommendations for mSSEPs and brainstem auditory evoked potentials were followed. Despite absence of the N20 responses from cortical mSSEPs no withdrawal from care was agreed upon. After awaking on day 7, mSSEPs were repeated and present. The patient survived and was discharged with minor deficits. Bilateral absence of N20 responses from mSSEPs performed beyond 48 hours after resuscitation from cardiac arrest is highly associated with bad neurological outcomes. However, variation due to hypothermia, noisy signals, medications, and brain hypo-perfusion must be taken into account.
Adult
;
Blood Pressure
;
Brain
;
Brain Stem
;
Critical Care Outcomes
;
Evoked Potentials, Auditory, Brain Stem
;
Evoked Potentials, Somatosensory
;
Heart Arrest
;
Humans
;
Hypothermia
;
Male
;
Median Nerve
;
Nervous System Diseases
;
Neurophysiology
;
Prognosis
;
Reflex
;
Reflex, Abnormal
;
Resuscitation
;
Thoracotomy
;
Thorax
;
Wounds, Gunshot
2.Neuromonitoring for Spinal Cord Stimulation Lead Placement Under General Anesthesia.
Journal of Clinical Neurology 2018;14(4):444-453
Spinal cord stimulation (SCS) is a common therapeutic technique for treating medically refractory neuropathic back and other limb pain syndromes. SCS has historically been performed using a sedative anesthetic technique where the patient is awakened at various times during a surgical procedure to evaluate the location of the stimulator lead. This technique has potential complications, and thus other methods that allow the use of a general anesthetic have been developed. There are two primary methods for placing leads under general anesthesia, based on 1) compound muscle action potentials and 2) collisions between somatosensory evoked potentials. Both techniques are discussed, and the literature on SCS lead placement under general anesthesia using intraoperative neurophysiological mapping is comprehensively reviewed.
Action Potentials
;
Anesthesia, General*
;
Evoked Potentials, Somatosensory
;
Extremities
;
Humans
;
Neurophysiology
;
Spinal Cord Stimulation*
;
Spinal Cord*
3.Update on the Pathophysiology and Management of Anorectal Disorders.
Tanisa PATCHARATRAKUL ; Satish S C RAO
Gut and Liver 2018;12(4):375-384
Anorectal disorders are common and present with overlapping symptoms. They include several disorders with both structural and functional dysfunction(s). Because symptoms alone are poor predictors of the underlying pathophysiology, a diagnosis should only be made after evaluating symptoms and physiologic and structural abnormalities. A detailed history, a thorough physical and digital rectal examination and a systematic evaluation with high resolution and/or high definition three-dimensional (3D) anorectal manometry, 3D anal ultrasonography, magnetic resonance defecography and neurophysiology tests are essential to correctly identify these conditions. These physiological and imaging tests play a key role in facilitating a precise diagnosis and in providing a better understanding of the pathophysiology and functional anatomy. In turn, this leads to better and more comprehensive management using medical, behavioral and surgical approaches. For example, patients presenting with difficult defecation may demonstrate dyssynergic defecation and will benefit from biofeedback therapy before considering surgical treatment of coexisting anomalies such as rectoceles or intussusception. Similarly, patients with significant rectal prolapse and pelvic floor dysfunction or patients with complex enteroceles and pelvic organ prolapse may benefit from combined behavioral and surgical approaches, including an open, laparoscopic, transabdominal or transanal, and/or robotic-assisted surgery. Here, we provide an update on the pathophysiology, diagnosis, and management of selected common anorectal disorders.
Biofeedback, Psychology
;
Constipation
;
Defecation
;
Defecography
;
Diagnosis
;
Digital Rectal Examination
;
Humans
;
Intussusception
;
Manometry
;
Neurophysiology
;
Pelvic Floor
;
Pelvic Organ Prolapse
;
Rectal Diseases
;
Rectal Prolapse
;
Rectocele
;
Ultrasonography
4.Intraoperative Neurophysiological Monitoring : A Review of Techniques Used for Brain Tumor Surgery in Children
Keewon KIM ; Charles CHO ; Moon suk BANG ; Hyung ik SHIN ; Ji Hoon PHI ; Seung Ki KIM
Journal of Korean Neurosurgical Society 2018;61(3):363-375
Intraoperative monitoring (IOM) utilizes electrophysiological techniques as a surrogate test and evaluation of nervous function while a patient is under general anesthesia. They are increasingly used for procedures, both surgical and endovascular, to avoid injury during an operation, examine neurological tissue to guide the surgery, or to test electrophysiological function to allow for more complete resection or corrections. The application of IOM during pediatric brain tumor resections encompasses a unique set of technical issues. First, obtaining stable and reliable responses in children of different ages requires detailed understanding of normal ageadjusted brain-spine development. Neurophysiology, anatomy, and anthropometry of children are different from those of adults. Second, monitoring of the brain may include risk to eloquent functions and cranial nerve functions that are difficult with the usual neurophysiological techniques. Third, interpretation of signal change requires unique sets of normative values specific for children of that age. Fourth, tumor resection involves multiple considerations including defining tumor type, size, location, pathophysiology that might require maximal removal of lesion or minimal intervention. IOM techniques can be divided into monitoring and mapping. Mapping involves identification of specific neural structures to avoid or minimize injury. Monitoring is continuous acquisition of neural signals to determine the integrity of the full longitudinal path of the neural system of interest. Motor evoked potentials and somatosensory evoked potentials are representative methodologies for monitoring. Free-running electromyography is also used to monitor irritation or damage to the motor nerves in the lower motor neuron level : cranial nerves, roots, and peripheral nerves. For the surgery of infratentorial tumors, in addition to free-running electromyography of the bulbar muscles, brainstem auditory evoked potentials or corticobulbar motor evoked potentials could be combined to prevent injury of the cranial nerves or nucleus. IOM for cerebral tumors can adopt direct cortical stimulation or direct subcortical stimulation to map the corticospinal pathways in the vicinity of lesion. IOM is a diagnostic as well as interventional tool for neurosurgery. To prove clinical evidence of it is not simple. Randomized controlled prospective studies may not be possible due to ethical reasons. However, prospective longitudinal studies confirming prognostic value of IOM are available. Furthermore, oncological outcome has also been shown to be superior in some brain tumors, with IOM. New methodologies of IOM are being developed and clinically applied. This review establishes a composite view of techniques used today, noting differences between adult and pediatric monitoring.
Adult
;
Anesthesia, General
;
Anthropometry
;
Brain Neoplasms
;
Brain
;
Child
;
Cranial Nerves
;
Electromyography
;
Evoked Potentials, Auditory, Brain Stem
;
Evoked Potentials, Motor
;
Evoked Potentials, Somatosensory
;
Humans
;
Infratentorial Neoplasms
;
Intraoperative Neurophysiological Monitoring
;
Longitudinal Studies
;
Monitoring, Intraoperative
;
Motor Neurons
;
Muscles
;
Neurophysiology
;
Neurosurgery
;
Peripheral Nerves
;
Prospective Studies
5.Cough Hypersensitivity Syndrome: A Few More Steps Forward.
Allergy, Asthma & Immunology Research 2017;9(5):394-402
Cough reflex is a vital protective mechanism against aspiration, but when dysregulated, it can become hypersensitive. In fact, chronic cough is a significant medical problem with a high degree of morbidity. Recently, a unifying paradigm of cough hypersensitivity syndrome has been proposed. It represents a clinical entity in which chronic cough is a major presenting problem, regardless of the underlying condition. Although it remains a theoretical construct, emerging evidence suggests that aberrant neurophysiology is the common etiology of this syndrome. Recent success in randomized clinical trials using a P2X3 receptor antagonist is the first major advance in the therapeutics of cough in the past 30 years; it at last provides a strategy for treating intractable cough as well as an invaluable tool for dissecting the mechanism underpinning cough hypersensitivity. Additionally, several cough measurement tools have been validated for use and will help assess the clinical relevance of cough in various underlying conditions. Along with this paradigm shift, our understanding of cough mechanisms has improved during the past decades, allowing us to continue to take more steps forward in the future.
Cough*
;
Hypersensitivity*
;
Neurophysiology
;
Receptors, Purinergic P2X3
;
Reflex
6.Apraxia: Review and Update.
Journal of Clinical Neurology 2017;13(4):317-324
Praxis, the ability to perform skilled or learned movements is essential for daily living. Inability to perform such praxis movements is defined as apraxia. Apraxia can be further classified into subtypes such as ideomotor, ideational and limb-kinetic apraxia. Relevant brain regions have been found to include the motor, premotor, temporal and parietal cortices. Apraxia is found in a variety of highly prevalent neurological disorders including dementia, stroke and Parkinsonism. Furthermore, apraxia has been shown to negatively affect quality of life. Therefore, recognition and treatment of this disorder is critical. This article provides an overview of apraxia and highlights studies dealing with the neurophysiology of this disorder, opening up novel perspectives for the use of motor training and noninvasive brain stimulation as treatment.
Apraxias*
;
Brain
;
Dementia
;
Nervous System Diseases
;
Neurophysiology
;
Parietal Lobe
;
Parkinsonian Disorders
;
Quality of Life
;
Stroke
7.Orthostatic Hypotension and Postural Orthostatic Tachycardia Syndrome in Children: Comparison of Clinical Features and Neurophysiology Test.
Yun Kyum KIM ; Ji Hyun PARK ; Hee Joung CHOI ; Joon Sik KIM
Journal of the Korean Child Neurology Society 2017;25(3):156-161
PURPOSE: The clinical characteristics and neuropsychological tests of orthostatic hypotension (OH) and postural orthostatic tachycardia syndrome (POTS) in children were compared. METHODS: From August 2011 to April 2015, we enrolled patients who visited hospital with dizziness or syncope. According to the results of head-up tilt test (HUTT), the patients were classified into 4 groups; OH group, POTS group, normal group I who had no orthostatic symptom during HUTT, and normal group II who had orthostatic symptom during HUTT. RESULTS: Eighty-eight patients were enrolled with 11(12.5%) in OH group, 13(14.7%) in POTS group, 49(55.7%) in normal group I and 15(17.0%) in the normal group II. During HUTT, the temporal changes of systolic, diastolic, and mean blood pressure of OH group were significantly different from those of POTS group, normal group I, and normal group II. Heart rate changes after tilt showed increase trend in all 4 groups and there was no significant different between OH and POTS group. In normal group II, the temporal changes of diastolic and mean blood pressure were similar to those in POTS group and were significantly different from normal group I. In the autonomic nervous system test, the heart rate response to deep breathing (HRDB) was significantly different between normal group I and II CONCLUSIONS: In pediatric OH patients, heart rate may be increased with blood pressure fall. And if orthostatic symptoms are associated with HUTT, we should not exclude OI even if the test result do not meet the criteria for diagnosis.
Autonomic Nervous System
;
Blood Pressure
;
Child*
;
Diagnosis
;
Dizziness
;
Heart Rate
;
Humans
;
Hypotension, Orthostatic*
;
Neurophysiology*
;
Neuropsychological Tests
;
Postural Orthostatic Tachycardia Syndrome*
;
Respiration
;
Syncope
8.Comparison of EEG Changes Induced by Action Execution and Action Observation.
Ji Young KIM ; Yu Min KO ; Ji Won PARK
Journal of Korean Physical Therapy 2017;29(1):27-32
PURPOSE: Recent electrophysiological studies have shown that the sensorymotor cortex is activated during both actual action excuted by themselves and observation of action performed by other persons. Observation of action based on mirror neuron system can be used as a cognitive intervention to promote motor learning. The purpose of this study was to investigate the brain activity changes during action observation and action execution using EEG. METHODS: Thirty healthy volunteers participated and were requested to perform hand action and to observe the video of hand action performed by another person. The EEG activity was evaluated by a method which segregated the time-locked for each condition. To compare the differences between action observation and execution, the Mu suppression and the relative band power were analysed. RESULTS: The results showed significant mu suppression during the action observation and execution, but the differences between the two conditions were not observed. The relative band power showed a significant difference during the action observation and execution, but there were no differences between the two conditions. CONCLUSION: These results indicate that action execution and observation involve overlapping neural networks in the sensorymotor cortical areas, proposing positive changes on neurophysiology. We are expected to provide information related to the intervention of cognitive rehabilitation.
Brain
;
Electroencephalography*
;
Hand
;
Healthy Volunteers
;
Humans
;
Learning
;
Methods
;
Mirror Neurons
;
Neurophysiology
;
Rehabilitation
9.Neurophysiology of Laryngopharyngeal Reflux and Brainstem Reflex.
Journal of the Korean Society of Laryngology Phoniatrics and Logopedics 2016;27(2):73-77
Laryngopharyngeal reflux disease (LPRD) is different with gastroesophageal reflux disease (GERD). The lower esophageal sphincter (LES) possesses an intrinsic nervous plexus that allows the LES to have a considerable degree of independent neural control. Sympathetic control of the LES and stomach stems from cholinergic preganglionic neurons in the intermediolateral column of the thoracic spinal cord (T6 through T9 divisions), which impinge on postganglionic neurons in the celiac ganglion, of which the catecholaminergic neurons provide the LES and stomach with most of its sympathetic supply. Sympathetic regulation of motility primarily involves inhibitory presynaptic modulation of vagal cholinergic input to postganglionic neurons in the enteric plexus. The magnitude of sympathetic inhibition of motility is directly proportional to the level of background vagal efferent input. Recognizing that the LES is under the dual control of the sympathetic and parasympathetic nervous systems, we refer the reader to other comprehensive reviews on the role of the sympathetic and parasympatetic control of LES and gastric function. The present review focuses on the functionally dominant parasympathetic control of the LES and stomach via the dorsal motor nucleus of the vagus.
Brain Stem*
;
Esophageal Sphincter, Lower
;
Ganglia, Sympathetic
;
Gastroesophageal Reflux
;
Laryngopharyngeal Reflux*
;
Neurons
;
Neurophysiology*
;
Parasympathetic Nervous System
;
Reflex*
;
Spinal Cord
;
Stomach
10.Neurophysiologic Mechanism of Pain.
Journal of Korean Society of Spine Surgery 2015;22(1):13-19
STUDY DESIGN: A review of the literature regarding neurophysiologic mechanism of pain. OBJECTIVES: To review and discuss neurophysiologic mechanism of pain, including neuropathic pain. SUMMARY OF LITERATURE REVIEW: The neurophysiology of pain has been established at the cellular and molecular biology level through many studies. Also, multiple modalities to manage pain have been developed. MATERIALS AND METHODS: A literature review. RESULTS: Pain develops by actions of multiple receptors, ion channels and neurotransmitters along the pain pathway. Pathologic states, such as persistent pain, allodynia, and hyperalgesia, arise from alteration of the pain pathway. Especially, neuropathic pain results from nerve injury and its pathology is rather different from the neuroplasty of normal individuals. CONCLUSION: Multiple modalities, including individualized pain treatment based on pain phenotype, are introduced. However, optimal treatment is uncertain, therefore, further studies are needed.
Hyperalgesia
;
Ion Channels
;
Molecular Biology
;
Neuralgia
;
Neuronal Plasticity
;
Neurophysiology
;
Neurotransmitter Agents
;
Pathology
;
Phenotype

Result Analysis
Print
Save
E-mail