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1.
Journal of Clinical Neurology ; : 36-43, 2023.
Article in English | WPRIM | ID: wpr-967105

ABSTRACT

Background@#and Purpose This study aimed to determine the ability of deep learning using convolutional neural networks (CNNs) to diagnose transient global amnesia (TGA) based on electroencephalography (EEG) data, and to differentiate between patients with recurrent TGA events and those with a single TGA event. @*Methods@#We retrospectively enrolled newly diagnosed patients with TGA and healthy controls. All patients with TGA and the healthy controls underwent EEG. The EEG signals were converted into images using time-frequency analysis with short-time Fourier transforms. We employed two CNN models (AlexNet and VGG19) to classify the patients with TGA and the healthy controls, and for further classification of patients with recurrent TGA events and those with a single TGA event. @*Results@#We enrolled 171 patients with TGA and 68 healthy controls. The accuracy and area under the curve (AUC) of the AlexNet and VGG19 models in classifying patients with TGA and healthy controls were 70.4% and 71.8%, and 0.718 and 0.743, respectively. In addition, the accuracy and AUC of the AlexNet and VGG19 models in classifying patients with recurrent TGA events and those with a single TGA event were 71.1% and 88.4%, and 0.773 and 0.873, respectively. @*Conclusions@#We have successfully demonstrated the feasibility of deep learning in diagnosing TGA based on EEG data, and used two different CNN models to distinguish between patients with recurrent TGA events and those with a single TGA event.

2.
Journal of Clinical Neurology ; : 573-580, 2023.
Article in English | WPRIM | ID: wpr-1000848

ABSTRACT

Background@#and Purpose We aimed to determine whether structural brain connectivity is significantly associated with the response to sumatriptan in patients with migraine. @*Methods@#We retrospectively enrolled patients with newly diagnosed migraine who underwent brain diffusion-tensor imaging (DTI) at the time of diagnosis, with regular follow-up for at least 6 months after the initial diagnosis. Patients were classified into good- and poor-responder groups according to their response to sumatriptan. We analyzed the structural connectivity using DTI by applying graph theory using DSI Studio software. @*Results@#We enrolled 59 patients (35 good responders and 24 poor responders) and 30 healthy controls. Global structural connectivity differed significantly between patients with migraine and healthy controls, while local structural connectivity differed significantly between good and poor responders. The betweenness centrality was lower in good responders than in poor responders in the left lateral geniculate thalamic nucleus (26.078 vs. 41.371, p=0.039) and right medial mediodorsal magnocellular thalamic nucleus (60.856 vs. 90.378, p=0.021), whereas was higher in good responders in the left lateral pulvinar thalamic nucleus (98.365 vs. 50.347, p=0.003) and right medial pulvinar thalamic nucleus (216.047 vs. 156.651, p=0.036). @*Conclusions@#We found that structural connectivity in patients with migraine differed from that in healthy controls. Moreover, the local structural connectivity varied with the response to sumatriptan, which suggests that structural connectivity is a useful factor for predicting how a patient will respond to sumatriptan.

3.
Journal of Sleep Medicine ; : 107-116, 2022.
Article in Korean | WPRIM | ID: wpr-968947

ABSTRACT

Our conventional understanding of fluid transport across the brain has significantly changed over the last decade after introduction of the concept of the glymphatic system and discovery of meningeal lymphatics. The glymphatic system is not a true anatomical structure but merely a functional system for cerebrospinal fluid (CSF) and interstitial fluid exchange, whereby the CSF enters the brain through the periarterial space. This movement is driven by a few potential driver mechanisms. The CSF thereafter travels to the interstitium facilitated by aquaporin 4 channels in the astrocytic end feet and subsequently through the interstitium via diffusion and convection/advection and finally exits through the perivenous space. In this review, we describe magnetic resonance imaging (MRI) techniques that have been used or may potentially be useful to analyze the glymphatic system, together with a brief summary and discussion of limitations. MRI, a widely used clinical modality, may potentially provide deeper understanding of the pathophysiology of various diseases based on the concept of the glymphatic system.

4.
Journal of Clinical Neurology ; : 290-297, 2022.
Article in English | WPRIM | ID: wpr-925221

ABSTRACT

Restless legs syndrome (RLS) is a common neurological illness marked by a strong desire to move one’s legs, usually in association with uncomfortable sensations. Recent studies have investigated brain networks and connectivity in RLS. The advent of network analysis has greatly improved our understanding of the brain and various neurological disorders. A few studies have investigated alterations in functional connectivity in patients with RLS. This article reviews functional connectivity studies of patients with RLS, which have identified significant alterations relative to healthy controls in several brain networks including thalamic, salience, default-mode, and small-world networks. In addition, network changes related to RLS treatment have been found, including to repetitive transcranial magnetic stimulation, transcutaneous spinal cord direct-current stimulation, and dopaminergic drugs. These findings suggest that the underlying pathogenesis of RLS includes alterations in the functional connectivity in the brain and that RLS is a network disorder.

5.
Journal of Clinical Neurology ; : 390-400, 2020.
Article | WPRIM | ID: wpr-833641

ABSTRACT

Background@#and Purpose: The aim of this study was to evaluate the structural and functional connectivities of brain network using graph theoretical analysis in neurologically asymptomatic patients with end-stage renal disease (ESRD). We further investigated the prevalence of cognitive impairment (CI) in ESRD patients and analyzed the association between network measures of brain connectivity and cognitive function. @*Methods@#We prospectively enrolled 40 neurologically asymptomatic ESRD patients, 40 healthy controls, and 20 disease controls. All of the subjects underwent diffusion-tensor imaging (DTI) and resting-state functional magnetic resonance imaging (rs-fMRI). We calculated measures of structural and functional connectivities based on DTI and rs-fMRI, respectively, and investigated differences therein between the ESRD patients and the healthy controls. We assessed cognitive function in the ESRD patients using the Korean version of the Consortium to Establish a Registry for Alzheimer’s Disease neuropsychological battery. @*Results@#The ESRD patients exhibited decreased global structural and functional brain connectivities, as well as alterations of network hubs compared to the healthy controls and disease controls. About 70% of the ESRD patients had CI. Moreover, ESRD patients without CI exhibited decreased global connectivity and alterations of network hubs. Furthermore, there was a significant positive association between measures of brain connectivity and cognitive function. @*Conclusions@#We found that ESRD patients exhibited decreased structural and functional brain connectivities, and that there was a significant association between brain connectivity and cognitive function. These alterations in the brain network may contribute to the pathophysiological mechanism of CI in ESRD patients.

6.
Journal of Clinical Neurology ; : 68-76, 2019.
Article in English | WPRIM | ID: wpr-719297

ABSTRACT

BACKGROUND AND PURPOSE: There is accumulating evidence that epilepsy is caused by network dysfunction. We evaluated the hub reorganization of subcortical structures in patients with focal epilepsy using graph theoretical analysis based on diffusion-tensor imaging (DTI). In addition, we investigated differences in the values of diffusion tensors and scalars, fractional anisotropy (FA), and mean diffusivity (MD) of subcortical structures between patients with focal epilepsy and healthy subjects. METHODS: One hundred patients with focal epilepsy and normal magnetic resonance imaging (MRI) findings and 80 age- and sex-matched healthy subjects were recruited prospectively. All subjects underwent DTI to obtain data suitable for graph theoretical analysis. We investigated the differences in the node strength, cluster coefficient, eigenvector centrality, page-rank centrality measures, FA, and MD of subcortical structures between patients with epilepsy and healthy subjects. RESULTS: After performing multiple corrections, the cluster coefficient and the eigenvector centrality of the globus pallidus were higher in patients with epilepsy than in healthy subjects (p=0.006 and p=0.008, respectively). In addition, the strength and the page-rank centrality of the globus pallidus tended to be higher in patients with epilepsy than in healthy subjects (p=0.092 and p=0.032, respectively). The cluster coefficient of the putamen was lower in patients with epilepsy than in healthy subjects (p=0.004). The FA values of the caudate nucleus and thalamus were significantly lower in patients with epilepsy than in healthy subjects (p=0.009 and p=0.007, respectively), whereas the MD value of the thalamus was higher than that in healthy subjects (p=0.005). CONCLUSIONS: We discovered the presence of hub reorganization of subcortical structures in focal epilepsy patients with normal MRI findings, suggesting that subcortical structures play a pivotal role as a hub in the epilepsy network. These findings further reinforce the idea that epilepsy is a network disease.


Subject(s)
Humans , Anisotropy , Caudate Nucleus , Connectome , Diffusion , Epilepsies, Partial , Epilepsy , Globus Pallidus , Healthy Volunteers , Magnetic Resonance Imaging , Prospective Studies , Putamen , Thalamus
7.
Journal of Clinical Neurology ; : 120-122, 2018.
Article in English | WPRIM | ID: wpr-738845

ABSTRACT

No abstract available.


Subject(s)
Aged , Humans , Headache
8.
The Journal of the Korean Society for Transplantation ; : 63-68, 2018.
Article in English | WPRIM | ID: wpr-716930

ABSTRACT

Induction therapy with basiliximab is widely administered after kidney transplantation to prevent acute rejection. Herein, we report a case of non-cardiogenic pulmonary edema induced by basiliximab. To the best of our knowledge, such case has not been reported to date in Korea. A 54-year-old man with polycystic kidney disease received kidney transplantation. As induction therapy, he was prescribed basiliximab. On day 4, the second dose of basiliximab was administered. The patient complained of acute hypoxia 23 hours later, which led to circulatory collapse. He was discharged 3 weeks later with stable renal function. Pulmonary edema was presumed to have been caused by increased pulmonary capillary permeability. A possible hypothesis for this event occurring after the second basiliximab injection is steroid-related effects. Non-cardiogenic pulmonary edema is a complication that might occur after basiliximab induction therapy. Physicians should be aware of this potentially life-threatening complication.


Subject(s)
Humans , Middle Aged , Hypoxia , Capillary Permeability , Kidney Transplantation , Kidney , Korea , Polycystic Kidney Diseases , Pulmonary Edema , Shock
9.
Journal of the Korean Neurological Association ; : 43-45, 2017.
Article in Korean | WPRIM | ID: wpr-105732

ABSTRACT

Optic perineuritis (OPN) is a rare form of orbital inflammatory disease of optic nerve sheath. The clinical presentation of OPN are known as distinct from demyelinating optic neuritis (ON). Recently, we have experienced a patient with bilateral idiopathic ON who had initial magnetic resonance imaging (MRI) feature of OPN. Serial MRI and funduscopic examination exhibited the bilateral ON findings. Serial MRI and funduscopic examination are needed in diagnosing OPN to differentiate to the temporal change of ON.


Subject(s)
Humans , Magnetic Resonance Imaging , Optic Nerve , Optic Neuritis , Orbit
11.
Journal of the Korean Neurological Association ; : 111-113, 2017.
Article in Korean | WPRIM | ID: wpr-25097

ABSTRACT

No abstract available.


Subject(s)
Magnetic Resonance Imaging , Multiple Sclerosis , Neurosyphilis
12.
Neurology Asia ; : 155-160, 2016.
Article in English | WPRIM | ID: wpr-625247

ABSTRACT

Objective: This study identified the incidence and risk factors for headache attributed to acute pyelonephritis. Methods: The inclusion criteria were patients who were admitted with acute pyelonephritis at our hospital and ≥ 18 years of age. The following exclusion criteria were used: 1) patients who could not express their headache because of mental deterioration, 2) the presence of meningitis or meningoencephalitis, or 3) structural lesions on brain computed tomography or magnetic resonance images that could cause headache. The primary outcome was headache attributed to acute pyelonephritis as a dependent variable. The differences were analyzed using demographic and laboratory profiles as independent variables. Additionally, correlation analysis was performedbetweenseverity of headache using VAS score and demographic and laboratory profiles including age, WBC, and CRP. Results: A total of 479 patients met the inclusion criteria for this study, and 97 patients developed headache attributed to acute pyelonephritis. Patients with headache were younger and more likely to be female, and had a lower incidence of diabetes than those without headache. However, laboratory profiles that reflected the severity of acute pyelonephritis were not predictive factors for headache. Multiple logistic regression analysis demonstrated that young age and non-diabetes were independently significant variables for the prediction of headache attributed to acute pyelonephritis. In addition, the VAS score was found to be negative correlated with age, whereas it was not correlated with WBC and CRP. Conclusions: We determined that headache attributed to acute pyelonephritis was relatively common, and it was related to demographic characteristics but not acute pyelonephritis severity.


Subject(s)
Pyelonephritis , Headache
13.
Journal of Clinical Neurology ; : 332-339, 2016.
Article in English | WPRIM | ID: wpr-125904

ABSTRACT

BACKGROUND AND PURPOSE: We investigated the potential role of serum procalcitonin in differentiating tuberculosis meningitis from bacterial and viral meningitis, and in predicting the prognosis of tuberculosis meningitis. METHODS: This was a retrospective study of 26 patients with tuberculosis meningitis. In addition, 70 patients with bacterial meningitis and 49 patients with viral meningitis were included as the disease control groups for comparison. The serum procalcitonin level was measured in all patients at admission. Differences in demographic and laboratory data, including the procalcitonin level, were analyzed among the three groups. In addition, we analyzed the predictive factors for a prognosis of tuberculosis meningitis using the Glasgow Coma Scale (GCS) at discharge, and the correlation between the level of procalcitonin and the GCS score at discharge. RESULTS: Multiple logistic regression analysis showed that a low level of procalcitonin (≤1.27 ng/mL) independently distinguished tuberculosis meningitis from bacterial meningitis. The sensitivity and specificity for distinguishing tuberculosis meningitis from bacterial meningitis were 96.2% and 62.9%, respectively. However, the level of procalcitonin in patients with tuberculosis meningitis did not differ significantly from that in patients with viral meningitis. In patients with tuberculosis meningitis, a high level of procalcitonin (>0.4 ng/mL) was a predictor of a poor prognosis, and the level of procalcitonin was negatively correlated with the GCS score at discharge (r=-0.437, p=0.026). CONCLUSIONS: We found that serum procalcitonin is a useful marker for differentiating tuberculosis meningitis from bacterial meningitis and is also valuable for predicting the prognosis of tuberculosis meningitis.


Subject(s)
Humans , Bacteria , Glasgow Coma Scale , Logistic Models , Meningitis, Bacterial , Meningitis, Viral , Prognosis , Retrospective Studies , Sensitivity and Specificity , Tuberculosis , Tuberculosis, Meningeal
14.
Journal of the Korean Neurological Association ; : 253-255, 2016.
Article in Korean | WPRIM | ID: wpr-69723

ABSTRACT

No abstract available.


Subject(s)
Optic Neuritis , Tuberculosis, Meningeal
15.
Korean Journal of Clinical Neurophysiology ; : 61-67, 2015.
Article in English | WPRIM | ID: wpr-216869

ABSTRACT

BACKGROUND: The aim of this study was to investigate the predictive value of snoring frequency in the diagnosis and severity of obstructive sleep apnea. METHODS: Patients who underwent polysomnography with one or more of the following characteristics were included: 1) sleepiness, non-restorative sleep, fatigue, or insomnia symptoms; 2) arousal due to cessation of breathing or the occurrence of gasping or choking when waking up; and 3) habitual snoring, breathing interruptions, or both, noted by a bed partner or other observer. We analyzed the differences in clinical and polysomnographic variables between patients with and without obstructive sleep apnea and investigated the associations of those variables with obstructive sleep apnea severity. RESULTS: One hundred ninety-three patients met the inclusion criteria, and 145 of the 193 patients were diagnosed with obstructive sleep apnea. Multiple logistic regression analysis showed that large neck circumference (p = 0.0054) and high snoring index (p = 0.0119) were independent predictors for obstructive sleep apnea. Moreover, between the obstructive sleep apnea severity groups, there was a strong tendency of difference in body mass index (p = 0.0441) and neck circumference (p = 0.0846). However, there was no significant difference in snoring frequency according to obstructive sleep apnea severity (p = 0.4914). CONCLUSIONS: We confirmed that snoring frequency is a predictor of obstructive sleep apnea. In addition, we showed for the first time that snoring frequency is not associated with obstructive sleep apnea severity, thus it is not a valuable marker for predicting obstructive sleep apnea severity.


Subject(s)
Humans , Airway Obstruction , Arousal , Body Mass Index , Diagnosis , Fatigue , Logistic Models , Neck , Polysomnography , Respiration , Sleep Apnea Syndromes , Sleep Apnea, Obstructive , Sleep Initiation and Maintenance Disorders , Snoring
16.
Journal of the Korean Neurological Association ; : 100-102, 2015.
Article in Korean | WPRIM | ID: wpr-195250

ABSTRACT

Hashimoto's encephalopathy is a neurological disorder associated with high titers of antithyroid antibodies. The common neurologic symptoms are seizure, stroke-like episode, or mental change. However other atypical presentations, such as aphasia, myoclonus, ataxia, and cognitive dysfunction have also been described. We report hear a 44-year-old woman with Hashimoto's encephalopathy. The patient presented with ocular flutter as a principal manifestation, which is rare in Hashimoto's encephalopathy.


Subject(s)
Adult , Female , Humans , Antibodies , Aphasia , Ataxia , Myoclonus , Nervous System Diseases , Neurologic Manifestations , Seizures
17.
Journal of the Korean Neurological Association ; : 57-59, 2015.
Article in Korean | WPRIM | ID: wpr-201751

ABSTRACT

No abstract available.


Subject(s)
Ataxia , Infarction , Internal Capsule , Stroke
18.
Journal of the Korean Neurological Association ; : 60-62, 2015.
Article in Korean | WPRIM | ID: wpr-201750

ABSTRACT

No abstract available.


Subject(s)
Blinking , Diplopia , Miller Fisher Syndrome
19.
Journal of Sleep Medicine ; : 34-38, 2015.
Article in English | WPRIM | ID: wpr-95514

ABSTRACT

OBJECTIVES: Documented risk factors for obstructive sleep apnea include advanced age, male gender, hypertension, large neck circumference, and obesity; but some controversy remains regarding the risk factors, especially in Asians. In this study, we evaluated the risk factors for obstructive sleep apnea in snoring patients, and also analyzed the risk factors that could predict the severity of obstructive sleep apnea. METHODS: The inclusion criteria were patients 1) who visited our hospital with a chief complaint of snoring as witnessed by a sleep partner and 2) who underwent overnight polysomnography. The primary endpoint was the presence of obstructive sleep apnea as a dependent variable. RESULTS: One hundred forty-seven patients met the inclusion criteria. Of the 147 patients, 109 patients were diagnosed with obstructive sleep apnea. Multivariate analysis showed that old age and large neck circumference were significant independent variables for predicting the presence of obstructive sleep apnea, whereas hypertension and large neck circumference were independent variables for predicting the severity of obstructive sleep apnea. CONCLUSIONS: We demonstrated that neck circumference can be used to predict the presence as well as the severity of obstructive sleep apnea in snoring Asian patients.


Subject(s)
Humans , Male , Asian People , Hypertension , Multivariate Analysis , Neck , Obesity , Polysomnography , Risk Factors , Sleep Apnea Syndromes , Sleep Apnea, Obstructive , Snoring
20.
Korean Journal of Clinical Neurophysiology ; : 15-20, 2014.
Article in English | WPRIM | ID: wpr-156822

ABSTRACT

BACKGROUND: Triphasic waves are one of the electroencephalographic patterns that can be usually seen in metabolic encephalopathy. The aim of this study is to compare the clinical and electrophysiologic profiles between patients with and without triphasic waves in metabolic encephalopathy, and reassess the significance of triphasic waves in metabolic encephalopathy. METHODS: We recruited 127 patients with metabolic encephalopathy, who were admitted to our hospital. We divided these admitted patients into two groups; those with and without triphasic waves. We analyzed the difference of duration of hospitalization, mortality rate during admission, Glasgow Coma Scale, severity of electroencephalographic alteration, and presence of acute symptomatic seizures between these two groups. RESULTS: Of the 127 patients with metabolic encephalopathy, we excluded 67 patients who did not have EEG, and 60 patients finally met the inclusion criteria for this study. Patients with triphasic waves had more severe electroencephalographic alterations, lower Glasgow Coma Scale, and more acute symptomatic seizures than those without triphasic waves. After adjusting the clinical variables, Glasgow Coma Scale and acute symptomatic seizures were only significantly different between patients with and without triphasic waves. CONCLUSIONS: We demonstrated that patients with triphasic waves in metabolic encephalopathy had more significant impairment of the brain function.


Subject(s)
Humans , Brain , Brain Diseases, Metabolic , Electroencephalography , Glasgow Coma Scale , Hospitalization , Metabolism , Mortality , Seizures
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