• Clinical and Experimental Pediatrics
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• 제59권10호
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• pp.395-401
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• 2016

Since the outbreak of the enterovirus 71 (EV71) infection in Malaysia in 1997, large epidemics of EV71 have occurred in the Asia-Pacific region. Many children and infants have died from serious neurological complications during these epidemics, and EV71 infection has become a serious public health problem in these areas. EV71 infection causes hand, foot and mouth disease (HFMD) in children, and usually resolves spontaneously. However, EV71 occasionally involves the central nervous system (CNS), and induces diverse neurological complications such as brainstem encephalitis, aseptic meningitis, and acute flaccid paralysis. Among those complications, brainstem encephalitis is the most critical neurological manifestation because it can cause neurogenic pulmonary hemorrhage/edema leading to death. The characteristic clinical symptoms such as myoclonus and ataxia, cerebrospinal fluid (CSF) pleocytosis, and brainstem lesions on magnetic resonance imaging, in conjunction with the skin rash of HFMD and the isolation of EV71 from a stool, throat-swab, or CSF sample are typical findings indicating CNS involvement of EV71 infection. Treatment with intravenous immunoglobulin and milrinone are recommended in cases with severe neurological complications from EV71 infection, such as brainstem encephalitis. Despite the recent discovery of receptors for EV71 in human cells, such as the scavenger receptor B2 and P-selection glycoprotein ligand 1, it is not known why EV71 infection predominantly involves the brainstem. Recently, 3 companies in China have completed phase III clinical trials of EV71 vaccines. However, the promotion and approval of these vaccines in various countries are problems yet to be resolved.

• Annals of Clinical Neurophysiology
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• 제7권2호
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• pp.80-82
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• 2005

Background: Idiopathic Parkinson's disease (IPD) is closely related to Lewy body pathology. Pathological changes in medullar oblongata and pontine tegmentum have been reported in patients with subclinical motor symptom. Vestibular evoked myogenic potential (VEMP) is mediated by vestibular nuclei in lower brainstem and reflects the function of lower brainstem. The purpose of our study is to estimate the lower brainstem function in IPD patients. Methods: Ten patients with idiopathic Parkinson's disease underwent VEMP test. The patients were divided into Hohn-Yahr (H-Y) stage I (unilateral motor involvement) group and H-Y stage II or more severe (bilateral motor involvement) group. VEMP results were compared between groups using Mann-Whitney U test. Results: Among patients, 6 patients showed abnormal VEMP (unilateral abnormality 2, bilateral abnormalities 4). Between H-Y stage I group and H-Y II,III group, there was no statistical difference in the results of VEMP. Conclusions: We concluded that the lower brainstem dysfunction reflected in VEMP could occur in IPD regardless of the progression of the disease.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1996년도 추계학술대회
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• pp.237-239
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• 1996

In this paper, we present the ABR(Auditory Brainstem Response) as a clinical application. ABRs are composed of several waves or peaks. In recent years, the use of ABRs has gained popularity as one of the methods of choice in determinig hearing thresholds of newborns and infants. We introduce labeling and computational methods of peak identification in ABR.

• Journal of Korean Neurosurgical Society
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• 제55권3호
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• pp.164-166
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• 2014

Ganglioglioma is an infrequent tumor of the central nervous system (CNS); mostly supratentorial region. But, they can occur anywhere in the central nervous system such as brainstem, cerebellopontine angle (CPA), thalamus, optic nerve and spinal cord. Although it occurs rarely, ganglioglioma should be included in the differential diagnosis of a posterior fossa mass because early recognition is important for treatment and patient counseling.

• The Korean Journal of Physiology and Pharmacology
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• 제1권3호
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• pp.241-249
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• 1997

The aim of the present study is to examine the brainstem sites where the electrical stimulation produces a suppression of dorsal horn neuron responses of neuropathic rats. An experimental neuropathy was induced by a unilateral ligation of L5-L6 spinal nerves of rats. Ten to 15 days after surgery, the spinal cord was exposed and single-unit recording was made on wide dynamic range (WDR) neurons in the dorsal horn. Neuronal responses to mechanical stimuli applied to somatic receptive fields were examined to see if they were modulated by electrical stimulation of various brainstem sites. Electrical stimulation of periaqueductal gray (PAG), n. raphe magnus (RMg) or n. reticularis gigantocellularis (Gi) significantly suppressed responses of WDR neurons -to both noxious and non-noxious stimuli. Electrical stimulation of other brainstem areas, such as locus coeruleus. (LC) and n. reticularis paragigantocellularis lateralis (LPGi), produced little or no suppression. Microinjection of morphine into PAG, RMg, or Gi also produced a suppression as similar pattern to the case of electrical stimulation, whereas morphine injection into LC or LPGi exerted no effects. The results suggest that PAG, NRM and Gi are the principle brainstem nuclei involved in the descending inhibitory systems responsible for the control of neuropathic pain. These systems are likely activated by endogenous opioids and exert their inhibitory effect by acting on WDR neurons in the spinal cord.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제32권4호
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• pp.137-143
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• 2021

Objectives: Despite the growing concern regarding the adverse effects related to problematic smartphone use (PSU), little is known about underlying morphologic changes in the brain. The brainstem is a deep brain structure that consists of several important nuclei associated with emotions, sensations, and motor functions. In this study, we sought to examine the difference in the volume of brainstem substructures among adolescents with and without PSU. Methods: A total of 87 Korean adolescents participated in this study. The PSU group (n=20, age=16.2±1.1, female:male=12:8) was designated if participants reported a total Smartphone Addiction Proneness Scale (SAPS) score of ≥42, whereas the remaining participants were assigned to the control group (n=67, age=15.3±1.7, female:male=19:48). High-resolution T1 magnetic resonance imaging was performed, and the volume of each of the four brainstem substructures [midbrain, pons, medulla, and superior cerebellar peduncle (SCP)] was measured. Analysis of covariance was conducted to reveal group differences after adjusting for effects of age, gender, whole brainstem volume, depressive symptoms, and impulsivity. Results: The PSU group showed a significantly smaller volume of the SCP than the control group (F=8.273, p=0.005). The volume of the SCP and the SAPS score were negatively correlated (Pearson's r=-0.218, p=0.047). Conclusion: The present study is the first to reveal an altered volume of the brainstem substructure among adolescents with PSU. This finding suggests that the altered white matter structure in the brainstem could be one of the neurobiological mechanisms underlying behavioral changes in PSU.

• Journal of Korean Neurosurgical Society
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• 제50권4호
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• pp.299-303
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• 2011

Objective : Brainstem metastases are rarely operable and generally unresponsive to conventional radiation therapy or chemotherapy. Recently, Gamma Knife Radiosurgery (GKRS) was used as feasible treatment option for brainstem metastasis. The present study evaluated our experience of brainstem metastasis which was treated with GKRS. Methods : Between November 1992 and June 2010, 32 patients (23 men and 9 women, mean age 56.1 years, range 39-73) were treated with GKRS for brainstem metastases. There were metastatic lesions in pons in 23, the midbrain in 6, and the medulla oblongata in 3 patients, respectively. The primary tumor site was lung in 21, breast in 3, kidney in 2 and other locations in 6 patients. The mean tumor volume was $1,517mm^3$ (range, 9-6,000), and the mean marginal dose was 15.9 Gy (range, 6-23). Magnetic Resonance Imaging (MRI) was obtained every 2-3 months following GKRS. Follow-up MRI was possible in 24 patients at a mean follow-up duration of 12.0 months (range, 1-45). Kaplan-Meier survival analysis was used to evaluate the prognostic factors. Results : Follow-up MRI showed tumor disappearance in 6, tumor shrinkage in 14, no change in tumor size in 1, and tumor growth in 3 patients, which translated into a local tumor control rate of 87.5% (21 of 24 tumors). The mean progression free survival was 12.2 months (range, 2-45) after GKRS. Nine patients were alive at the completion of the study, and the overall mean survival time after GKRS was 7.7 months (range, 1-22). One patient with metastatic melanoma experienced intratumoral hemorrhage during the follow-up period. Survival was found to be associated with score of more than 70 on Karnofsky performance status and low recursive partitioning analysis class (class 1 or 2), in terms of favorable prognostic factors. Conclusion : GKRS was found to be safe and effective for management of brainstem metastasis. The integral clinical status of patient seems to be important in determining the overall survival time.

• Journal of Korean Neurosurgical Society
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• 제52권6호
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• pp.534-540
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• 2012

Objective : Brainstem arteriovenous malformation (AVM) is rare and radiosurgical management is complicated by the sensitivity of the adjacent neurological structures. Complete obliteration of the nidus is not always possible. We describe over 20 years of radiosurgical procedures for brainstem AVMs, focusing on clinical outcomes and radiosurgical techniques. Methods : Between 1992 and 2011, the authors performed gamma knife radiosurgery (GKRS) in 464 cerebral AVMs. Twenty-nine of the 464 patients (6.3%) reviewed had brainstem AVMs. This series included sixteen males and thirteen females with a mean age of 30.7 years (range : 5-71 years). The symptoms that led to diagnoses were as follows : an altered mentality (5 patients, 17.3%), motor weakness (10 patients, 34.5%), cranial nerve symptoms (3 patients, 10.3%), headache (6 patients, 20.7%), dizziness (3 patients, 10.3%), and seizures (2 patients, 6.9%). Two patients had undergone a previous nidus resection, and three patients had undergone a previous embolization. Twenty-four patients underwent only GKRS. With respect to the nidus type and blood flow, the ratio of compact type to diffuse type and high flow to low flow were 17 : 12 and 16 : 13, respectively. In this series, 24 patients (82.8%) had a prior hemorrhage. The mean target volume was 1.7 $cm^3$ (range 0.1-11.3 $cm^3$). The mean maximal and marginal radiation doses were 38.5 Gy (range 28.6-43.6 Gy) and 23.4 Gy (range 18-27 Gy), and the mean isodose profile was 61.3% (range 50-70%). Results : Twenty-four patients had brainstem AVMs and were followed for more than 3 years. Obliteration of the AVMs was eventually documented in 17 patients (70.8%) over a mean follow-up period of 77.5 months (range 36-216 months). With respect to nidus type and blood flow, the obliteration rate of compact types (75%) was higher than that of diffuse types (66.7%), and the obliteration rate of low flow AVMs (76.9%) was higher than that of high flow AVMs (63.6%) (p<0.05). Two patients (6.9%) with three hemorrhagic events suffered a hemorrhage during the follow-up period. The annual bleeding rate of AVM after GKRS was 1.95% per year. No adverse radiation effects or delayed cystic formations were found. Conclusion : GKRS has an important clinical role in treatment of brainstem AVMs, which carry excessive surgical risks. Angiographic features and radiosurgical techniques using a lower maximal dose with higher isodose profiles are important for lesion obliteration and the avoidance of complications.

• 한국임상수의학회지
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• 제40권4호
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• pp.260-267
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• 2023

Specialized hearing tests for pets are currently in demand. A brainstem auditory evoked response (BAER) test is an objective, non-invasive, and practical electrophysiological method that records electric signals from the peripheral auditory system to the brainstem when an auditory stimulation is provided. In veterinary medicine, sedation or anesthesia is essential for a successful examination. In human medicine, research has established the indications for various sedatives, anesthetics, and drugs according to the depth of anesthesia required. However, in veterinary medicine, there are very few comparative studies on propofol or isoflurane, which are the most common anesthetics used. Therefore, the present study aimed to analyze the difference in BAER test results between sedation with medetomidine, anesthesia using propofol, and inhalation anesthesia with isoflurane after propofol administration. The test was conducted on four healthy adult dogs. There was no statistically significant difference in latency, interpeak latency, or amplitude between the various drugs. The results suggest that a sedative or anesthetic for the administration of a BAER test can be selected according to the patient's needs.

• The Korean Journal of Physiology and Pharmacology
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• 제21권2호
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• pp.179-188
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• 2017

With the explosive increase in exposure to radiofrequency electromagnetic fields (RF-EMF) emitted by mobile phones, public concerns have grown over the last few decades with regard to the potential effects of EMF exposure on the nervous system in the brain. Many researchers have suggested that RF-EMFs can effect diverse neuronal alterations in the brain, thereby affecting neuronal functions as well as behavior. Previously, we showed that long-term exposure to 835 MHz RF-EMF induces autophagy in the mice brain. In this study, we explore whether shortterm exposure to RF-EMF leads to the autophagy pathway in the cerebral cortex and brainstem at 835 MHz with a specific absorption rate (SAR) of 4.0 W/kg for 4 weeks. Increased levels of autophagy genes and proteins such as LC3B-II and Beclin1 were demonstrated and the accumulation of autophagosomes and autolysosomes was observed in cortical neurons whereas apoptosis pathways were up-regulated in the brainstem but not in the cortex following 4 weeks of RF exposure. Taken together, the present study indicates that monthly exposure to RF-EMF induces autophagy in the cerebral cortex and suggests that autophagic degradation in cortical neurons against a stress of 835 MHz RF during 4 weeks could correspond to adaptation to the RF stress environment. However, activation of apoptosis rather than autophagy in the brainstem is suggesting the differential responses to the RF-EMF stresses in the brain system.