• Sleep Medicine and Psychophysiology
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• v.28 no.2
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• pp.53-69
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• 2021

Sleep disorders, increasingly prevalent in the general population, induce impairment in daytime functioning and other clinical problems. As changes in cortical excitability have been reported as potential pathophysiological mechanisms underlying sleep disorders, multiple studies have explored clinical effects of modulating cortical excitability through non-invasive brain stimulation in treating sleep disorders. In this study, we critically reviewed clinical studies using non-invasive brain stimulation, particularly transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), for treatment of sleep disorders. Previous studies have reported inconsistent therapeutic effects of TMS and tDCS for various kinds of sleep disorders. Specifically, low-frequency repetitive TMS (rTMS) and cathodal tDCS, both of which exert an inhibitory effect on cortical excitability, have shown inconsistent therapeutic effects for insomnia. On the other hand, high-frequency rTMS and anodal tDCS, both of which facilitate cortical excitability, have improved the symptoms of hypersomnia. In studies of restless legs syndrome, high-frequency rTMS and anodal tDCS induced inconsistent therapeutic effects. Single TMS and rTMS have shown differential therapeutic effects for obstructive sleep apnea. These inconsistent findings indicate that the distinctive characteristics of each non-invasive brain stimulation method and specific pathophysiological mechanisms underlying particular sleep disorders should be considered in an integrated manner for treatment of various sleep disorders. Future studies are needed to provide optimized TMS and tDCS protocols for each sleep disorder, considering distinctive effects of non-invasive brain stimulation and pathophysiology of each sleep disorder.

• Journal of Korean Neurosurgical Society
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• v.65 no.3
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• pp.457-468
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• 2022

Objective : The clinical management paradigm of skull base chordomas is still challenging. Surgical resection plays an important role of affecting the prognosis. Endonasal endoscopic approach (EEA) has gradually become the preferred surgical approach in most cases, but traditional transcranial surgery cannot be completely replaced. This study presents a comparison of the results of the two surgical strategies and a summary of the treatment algorithms for skull base chordomas. Methods : We retrospectively analyzed the surgical outcomes and follow-up data of 48 patients with skull base chordomas diagnosed pathologically who received transnasal midline approaches (TMA) and transcranial lateral approaches (TLA) from 2010 to 2020. Results : Among the 48 patients, 36 cases were adopted TMA and 12 cases were performed with TLA. In terms of gross total resection (GTR) rate, 27.8% in TMA and 16.7% in TLA and with EEA alone it was increased to 38.9%, while 29.7% in primary surgery. In TMA, the cerebrospinal fluid (CSF) leak remains the most common complication (13 cases, 36.1%), other main complications included death, cranial nerve palsy, hypopituitarism, all the comparisons were no statistical significance. The Karnofsky Performance Scale scores in TMA were all better than those in TLA at different time, and the overall survival (OS) and recurrence free survival/progression free survival was just the reverse. Conclusion : The EEA for skull base chordomas resection has improved the GTR rate, but transcranial approach is still an alternative approach. It is necessary to select an appropriate surgical approach based on the location and the pattern of tumor growth in order to obtain the best surgical outcomes.

• Annals of Clinical Neurophysiology
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• v.13 no.1
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• pp.1-12
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• 2011

Transcranial magnetic stimulation (TMS) is a non-invasive tool used to study aspects of human brain physiology, including motor function and the pathophysiology of various brain disorders. A brief electric current passed through a magnetic coil produces a high-intensity magnetic field, which can excite or inhibit the cerebral cortex. Although various brain regions can be evaluated by TMS, most studies have focused on the motor cortex where motor evoked potentials (MEPs) are produced. Single-pulse and paired-pulse TMS can be used to measure the excitability of the motor cortex via various parameters, while repetitive TMS induces cortical plasticity via long-term potentiation or long-term depression-like mechanisms. Therefore, TMS is useful in the evaluation of physiological mechanisms of various neurological diseases, including movement disorders and epilepsy. In addition, it has diagnostic utility in spinal cord diseases, amyotrophic lateral sclerosis and demyelinating diseases. The therapeutic effects of repetitive TMS on stroke, Parkinson disease and focal hand dystonia are limited since the duration and clinical benefits seem to be temporary. New TMS techniques, which may improve clinical utility, are being developed to enhance clinical utilities in various neurological diseases.

• Journal of Magnetics
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• v.19 no.1
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• pp.20-27
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• 2014

This study examined the relationships between protein expression and Poly ADP ribose polymerase in brain cell death in brains damaged by thrombotic stroke and treated with the Full Wave- Cockroft Walton (FWCW) method of Transcranial Magnetic Stimulation (TMS). The two-way switching element for TMS drove a half-bridge inverter of the current resonance of direct current voltage (+) and direct current voltage (-), and the experiment was conducted by stimulating the mice with thrombotic stroke through a range of pulses. Thrombotic stroke was caused of ligation of the common carotid artery of male SD mice, and blood reperfusion was conducted five minutes later. Protein expression was examined in immune reaction cells, which reacted to an antibody to Poly ADP ribose polymerase in the cerebrum cells, and western blotting. Observations of the PARP changes after thrombotic stroke showed that the number of Poly ADP ribose polymerase reactions were significantly lower (p < 0.05) in the group treated with TMS of the FWCW than the group with thrombotic stroke 24 hours after its onset. The application of FWCW-TMS helped prevent the necrosis of nerve cells and might prevent the brain damage that occurs as a result of thrombotic stroke, and improve the function recovery and disorder of brain cells.

• The korean journal of orthodontics
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• v.21 no.2 s.34
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• pp.399-418
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• 1991

This study was designed to evaluate the relationship of mandibular condylar position to overbite depth and compare the findings from transcranial radiographs and those, from individualized corrected tomographs in determination of condylar position. The subjects consisted of 20 control subjects (male 8, female 12), and 10 open-bite patients (male 3, female 7) and 23 deep-bite patients (male 17, female 6). The mean age was 23.3 years for the control group, 21.5 years for open-bite group, and 23.2 years for deep-bite group. Transcranial radiographys and individualized corrected tomographys in centric occlusion were taken from right and left temporomandibular joints of each sueject. The results were as follows. 1. In the 20 normal subjects showing no symptoms of TM disorder, the incidence of condylar retrusion was $27.5\%$, middle condylar position $60.0\%$, and anterior displacement $12.5\%$. 2. There was significant correlation between the bite depth and observed condylar position. 3. Only $45.2\%$ of the findings from transcranial radiographs coincided with those from individualized corrected tomographs in determining condylar position.

• Annals of Clinical Neurophysiology
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• v.1 no.1
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• pp.76-79
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• 1999

The most significant factor in pathogenesis of vascular headaches like migraine and cluster headache is dynamic changes of diameters of the cerebral arteries. TCD is a valuable noninvasive tool to assess the cerebral hemodynamic status by measuring the flow velocities of the intracranial cerebral arteries around the circle of Willis. TCD can evaluate flow velocities and vasoreactivity of the patients with a vascular headache during the ictal phase as well as during intericatal phase. Distribution of the changes recorded differ between types of headaches and also between the major ictal symptoms. The changes suggest the presence of prolonged vasospasm interictally and more marked relaxation of the cerebral arteries. TCD can be used to monitor the long-term clinical course of patients with vascular headache by correlation the symptomatic improvement and TCD data before and after long-term pharmacological prophylactic treatments. During the ictal phases large intervention. The results may be used in selecting and evaluating the agents for abortive therapy for acute attacks. In conclusion TCD can quantitatively evaluate vascular headaches when making diagnosis and classification and can provide guidelines to choose more individualized therapeutic options for both acute and long-term treatment.

• Journal of Korean Neurosurgical Society
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• v.44 no.2
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• pp.63-66
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• 2008

Objective : The purpose of this study is to investigate the correlation between various transcranial Doppler (TCD) ultrasonography parameters and clinical vasospasm after aneurysmal subarachnoid hemorrhage (SAH). Methods : This study enrolled 40 patients presented with aneurysmal SAH between September 2006 and August 2007. We measured differences of mean blood flow velocity (BFVm), highest systolic blood flow velocity (BFVh), and Lindegaard ratio (LR) in the middle cerebral artery on TCD examination. These parameters were evaluated for correlation with clinical vasospasm by univariate analysis and the receiver operating characteristic analysis. Results : Twelve patients (30%) developed clinical vasospasm. The best TCD parameters for the detection of clinical vasospasm were revealed to be differences of BFVm, BFVh, and LR values between $1^{st}$ TCD test and $3^{rd}$ TCD (7 cm/s. 11.5 cm/s, 0.45 respectively). The positive predictive value of anyone of three parameters was 60% and the negative predictive value was 100%. Conclusion : TCD is still considered a useful tool for screening clinical vasospasm. To confirm the predictive value of the above parameters. further prospective study will be needed.

• Journal of Magnetics
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• v.19 no.4
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• pp.353-356
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• 2014

The aim of the present study was to examine whether mental practice (MP) in conjunction with repetitive transcranial magnetic stimulation (rTMS) can improve the upper limb function of sub-acute stroke patients. This study was conducted with 32 subjects who were diagnosed with hemiparesis by stroke. The experimental group consisted of 16 members upon each of whom was performed MP in conjunction with rTMS, whreas the control group consisted of 16 members upon each of whom was performed MP and sham rTMS. Both groups received traditional physical therapy for 30 minutes a day, 5 days a week, for 6 weeks; additionally, they received mental practice for 15 minutes a day. The experimental group was instructed to perform rTMS, and the control group was instructed to apply sham rTMS for 15 minutes. A motor cortex excitability analysis was performed by motor evoked potentials (MEPs), and upper limb function was evaluated by Fugl-Meyer Assessment (FMA) and the Box and Block test (BBT). Results showed that the amplitude, latency, FMA, and BBT of the experimental group and the latency, FMA, and BBT of the control group were significantly improved after the experiment (p<0.05). Significant differences were found between the groups in amplitude and latency after the experiment (p<0.05). The results showed that MP in conjunction with rTMS is more effective in improving upper limb function than MP alone.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.19 no.1
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• pp.151-159
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• 1989

The author has studied radiographic bony cnages of mandibular condyle head in temporomandibular disorder patients using Oblique lateral transcranial projection, Orthopantomography, and Tomography. The bony change types and the frequencies of occurrence and the incidences of bony changes in three different radiographic techniques were examined. The coincidences of bony change types between the Oblique lateral transcranial projection and the lateral part of Tomogram, the Orthopantomogram and the medial part of Tomogram were also examined. The results were as follows: 1. The mean age of patients was 31.7 years and under 40 years were 24 patients, women werw 27 patients, men were 4patients. 2. The observable case of bony changes in all three radiographic techniques were 19 cases (50%) of 38 cases and the observable cases of bony changes in only Tomography were 5 cases(13.2%) 3. The most frequent radiographic bony change type was osteophyte and next orders were flattening, erosion, concavity. 4. The positional incidences of bony change in Tomogram were 31 cases in lateral part and 27 cases in central part. 5. The coincidence of bony change types between the Oblique lateral transcranial projection and the lateral part of Tomogram was 80%, and the coincidence between the Orthopantomogram and the medial part or Tomogram was 76.0%.

• Journal of Magnetics
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• v.20 no.4
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• pp.427-431
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• 2015

The aim of this study was to investigate whether repetitive transcranial magnetic stimulation (rTMS) can improve motor recovery in the lower extremities of the patients with subacute stage spinal cord injury (SCI). This study was conducted with 19 subjects diagnosed with paraplegia because of SCI. The experimental group included 10 subjects who underwent active rTMS, and the control group included 9 subjects who underwent sham rTMS. The SCI patients in the experimental group underwent conventional rehabilitation therapy, and active rTMS was applied daily to the hotspot of the lesional hemisphere. The SCI patients in the control group underwent sham rTMS and conventional rehabilitation therapy. The participants in both the groups received therapy five days per week for six weeks. Latency, amplitude, and velocity were assessed before and after the six-week therapy period. A significant difference in post-treatment gains for the latency and velocity was observed between the experimental and control groups (p < 0.05). However, no significant differences in the amplitude were observed between the two groups (p > 0.05). The results of this study indicate that rTMS may be beneficial in improving motor recovery in the lower extremities of subacute stage SCI patients.