• Annals of Clinical Neurophysiology
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• v.1 no.2
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• pp.160-167
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• 1999

Although somatosensory evoked potentials(SSEPs) have been utilized as the useful diagnostic tools in evaluating the wide variety of pathological conditions, such as focal lesions affecting the somatosensory pathways, demyelinating diseases, and detecting the clinically occult abnormality, their neural generators is still considerably uncertain. To appreciate the basis for uncertainties about the origins of SSEPs, consider criteria that must be met to establish a causal relationship between activity in a neural structure and a spine/ scalp-recorded potential. Electrode locations and channel derivations for SSEPs recordings are based on two principles:(1) the waveforms are best recorded from electrode sites on the body surface closest to the presumed generator sources along the somatosensory pathways, and(2) studies of the potential-field distribution of each waveform of interest dictate the best techniques to be used. In this article, authors will describe followings focused on ;(1) the concepts of near field potentials(NFPs) and far field potentials(FFPs) - the voltage of NFPs is highly dependent upon recording electrode position, FFPs are unlike NFPs in that they are widely distributed, their latencies and amplitudes are independent of recording electrode.(2) appropriate montage settings to detect the significant potentials in the median nerve and posterior tibial nerve SSEPs(3) neural generators of various potentials(P9, N13, P14, N18, N20, P37) and their clinical significance in interpretating the results of SSEPs. Especially, Characteristics of N18(longduration, small superimposed inflection) suggested that N18 is a complex wave with multiple generators including brainstem structures and thalamic nuclei. And N18 might be used as the parameter of braindeath. Precise understanding on these facts provide an adequate basis utilizing SSEPs for numerous clinical purposes.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.1197-1198
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• 2012

• Journal of International Academy of Physical Therapy Research
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• v.3 no.2
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• pp.429-434
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• 2012

Ischemia, the leading cause of strokes, is known to be deeply related to synaptic plasticity and apoptosis in tissue damage due to ischemic conditions or trauma. The purpose of this study was to research the effects of NEES(needle electrode electrical stimulation) in brain cells of ischemia-induced rat, more specifically the effects of Poly[ADP-ribose] polymerase(PARP) on the corpus striatum. Ischemia was induced in SD mice by occluding the common carotid artery for 5 minutes, after which blood was re-perfused. NEES was applied to acupuncture points, at 12, 24, and 48 hours post-ischemia on the joksamri, and at 24 hours post-ischemia on the hapgok. Protein expression was investigated through PARP antibody immuno-reactive cells in the cerebral nerve cells and western blotting. The number of PARP reactive cells in the corpus striatum 24 hours post-ischemia was significantly(p<.05) smaller in the NEES group compared to the global ischemia(GI) group. PARP expression 24 hours post-ischemia was very significantly smaller in the NEES group compared to the GI group. Results show that ischemia increases PARP expression and stimulates necrosis, making it a leading cause of death of nerve cells. NEES can decrease protein expression related to cell death, protecting neurons and preventing neuronal apoptosis.

• The Korean Journal of Pain
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• v.23 no.3
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• pp.198-201
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• 2010

Persistent and intractable hiccups (with respective durations of more than 48 hours and 1 month) can result in depression, fatigue, impaired sleep, dehydration, weight loss, malnutrition, and aspiration syndromes. The conventional treatments for hiccups are either non-pharmacological, pharmacological or a nerve block treatment. Pulsed radiofrequency lesioning (PRFL) has been proposed for the modulation of the excited nervous system pathway of pain as a safe and nondestructive treatment method. As placement of the electrode in close proximity to the targeted nerve is very important for the success of PRFL, ultrasound appears to be well suited for this technique. A 74-year-old man suffering from intractable hiccups that had developed after a coronary artery bypass graft and had continued for 7 years was referred to our pain clinic. He had not been treated with conventional methods or medications. We performed PRFL of the phrenic nerve guided by ultrasound and the hiccups disappeared.

• Journal of Acupuncture Research
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• v.21 no.6
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• pp.249-257
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• 2004

Objective : Radial nerve palsy is characterized by palsy or paralysis of extensors of the wrist and digits, as well as the forearm supinators. Very proximal lesions also may affect the triceps. Numbness occurs on the dorsoradial aspect of the hand and the dorsal aspect of the radial 3 and 1/2 digits. We observed 7 patients with radial nerve palsy, the results are as follows. Methods & Results : All patients were treated by the same method and treatment was performed by acupuncture and Neuromuscular Electrical Stimulation. the electrode were placed unilaterally on the motor points of forearm. As the result, symptoms are improved remarkably. Conclusions : Patients were treated for 5.4 weeks, 14.7 times(average). The grade was that 6 cases were good and 1 case was excellent.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.1
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• pp.60-68
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• 2010

In case of sensorineural hearing loss, auditory perception can be activated by electrical stimulation of the nervous system via electrode implanted into the cochlea or auditory nerve. Since the tonotopic map of the human auditory nerve has not been definitively identified, the recording of auditory nerve signal with microelectrode is desirable for determining the tonotopic map. This paper proposes the multi-channel analog front-end for auditory nerve signal detection. A channel of the proposed analog front-end consists of an AC coupling circuit, a low-power 4th-order Gm-C LPF, and a single-slope ADC. The AC coupling circuit transfers only AC signal while it blocks DC signal level. Considering the bandwidth of the auditory signal, the Gm-C LPF is designed with OTAs adopting floating-gate technique. For the channel-parallel ADC structure, the single-slope ADC is used because it occupies the small silicon area. Experimental results shows that the AC coupling circuit and LPF have the bandwidth of 100 Hz - 6.95 kHz and the ADC has the effective resolution of 7.7 bits. The power consumption per a channel is $12\;{\mu}W$, the power supply is 3.0 V, and the core area is $2.6\;mm\;{\times}\;3.7\;mm$. The proposed analog front-end was fabricated in a 1-poly 4-metal $0.35-{\mu}m$ CMOS process.

• The Korean Journal of Pain
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• v.29 no.1
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• pp.23-28
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• 2016

Background: Sacral nerve stimulation is a therapeutic option with demonstrated efficacy for conditions presenting with perineal pain caused by different etiologies. We aimed to assess whether a sacral electrode ($Interstim^{(R)}$, Medtronic, Minneapolis, MN, USA) inserted through the caudal pathway is able to offer an acceptable level of sacral stimulation and rate of catheter migration. Methods: We present 12 patients with pelvic pain who received sacral neuromodulation via the sacral hiatus with the InterStim electrode. We evaluated patient satisfaction as well as migration and removal of the electrode, if necessary. Results: Our experience included 12 patients, 10 women and two men, with a mean age of 60 years. In eight of the 12 patients, the initial therapy was effective, and the final system implantation was performed. During subsequent follow-up, patient satisfaction was good. To date, there have been no cases of electrode displacement or migration. Conclusions: The caudal insertion of the InterStim electrode, with its own fixation system, and initially designed for transsacral insertion, appears in our experience to be a satisfactory option which can minimize electrode displacements, achieving similar results in therapeutic efficacy and causing no difficulties in removal.

• Restorative Dentistry and Endodontics
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• v.16 no.2
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• pp.85-98
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• 1991

The aim of this study was to investigate the effect of low - power laser used in the medical field for various purposes to suppress pain responses evoked by noxious electrical or mechanical stimuli. After both inferior alveolar nerves and the left anterior digastric muscle of cats under general anesthesia were exposed, a recording electrode for the jaw opening reflex was inserted into the anterior digastric muscle. The right inferior alveolar nerve was dissected under a surgical microscope until the response of the functional single nerve could be evoked by the electrical stimulation of the dental pulp or oral mucosa. The electrical stimulus was applied with a rectangular pulse of 10 ms duration for measuring the threshold intensity of a single nerve fiber in the inferior alveolar nerve which responds to stimulation of dental pulp and oral mucosa. Then a pulse of 1 ms duration was applied for determination of conduction velocity. A noxious mechanical stimulus to the oral mucosa was applied by clamping the receptive field with an arterial clamp. The Ga-As diodide laser(wave length, 904 nm ; frequency, 1,000 Hz) was irradiated to the prepared tooth cavity, inferior alveolar nerve and oral mucosa as a pulse wave of 2 mW for 6 minutes. This was followed by a continuous wave of 15 mW for 3 minutes. The action potential of the nerve and EMG of the digastric muscle evoked by the noxious electrical stimulus and nerve response to noxious mechanical stimulus were compared at intervals of before, immediately after, and at 5, 10, 20, 40, 60 minutes after laser irradiation. The results were as follows: The conduction velocity of the intrapulpal $A{\delta}$- nerve fiber recorded from the inferior alveolar nerve before irradiation had a mean value of $6.68{\pm}2.07m/sec$. The laser irradiation did not affect the conduction velocity of the AS - nerve fiber and did not change the threshold intensity or amplitude of the action potential either. The EMG of the digastric muscle evoked by noxious electrical stimulation to the tooth was not changed by the laser irradiation, whether in latency, threshold intensity or amplitude. The laser irradiated to the receptive field of the oral mucosa which was subjected to noxious stimuli did not affect the amplitude of the action potential or the frequency either.

• Annals of Clinical Neurophysiology
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• v.6 no.2
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• pp.98-102
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• 2004

Background: Carpal tunnel syndrome (CTS) is a common condition characterized by entrapment neuropathy of the median nerves. Clinical manifestations are the most important findings for diagnosis and assessment of therapeutic effects. But, objective indicators, such as electrophysiological findings, are also valuable supplementary tools. This study investigated the relationship between clinical grading and sensory nerve conduction velocity (SNCV) of median proper palmar digital nerve (MPPDN) in CTS patients. Method: This study was done on 90 upper limbs of 53 patients with CTS (men: 6, women: 47, age: 26~69 years, mean age; 52 years). Each SNCV of MPPDN was recorded with bar electrode using antidromic method. Each SNCV was compared with clinical grading of CTS. The clinical grades of CTS were designated as follows; group 1 is mild symptoms, 2 is moderate symptoms, and 3 is severe and longstanding symptoms. Result: In thumb, the SNCV of MPPDN was not different significantly between 3 groups (p=0.817). In the index finger, the SNCV was the fastest in the group 1, but faster in group 3 than in group 2 (p=0.001). In the middle and ring fingers, SNCV was decreased in higher clinical grading groups (middle finger: p=0.015, ring finger: p=0.044). Conclusion: SNCV of MPPDN of middle and ring finger correlated with the clinical grading of CTS. SNCV of index finger was the fastest in group 1. But SNCV of thumb did not correlate with the clinical grading of CTS.

• The Korean Journal of Physiology
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• v.2 no.2
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• pp.75-81
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• 1968

According to recent observations of Cohen et al. the patterns of vestibular eye movements of rabbits are different from those of cats. However, the causes of such difference of the reflex eye movements in these species are not wholly explained. While the accumulated data obtained from cats appear to be established, experimental evidences in rabbits are rather meager. The author had re-examined the reflex eye movements of rabbits and attempted to find a mechanism which causes such difference in the reflex eye movements between two species. In anesthesized rabbit, unilateral individual semicircular canal nerve was stimulated selectively with a fine insulated electrode which was inserted through a hole made on the corresponding osseous canal, under a dissecting microscope. When an individual canal nerve was stimulated, the reflex movements of both eyes were observed, photographed, and recorded kymographically. Extraocular muscles were also studied to find their morphological characteristics and to correlate them with the function of the muscles. 1. At the beginning of the stimulation, both eyes moved to a specific direction depending upon the canal stimulated, and such directional eye movements were sustained during the whole course of stimulation. Amplitude of the eye movement showed graded responses to the increasing frequency of the stimulus, reaching to the maximal response at 200-300 cps. 2. Stimulation of the unilateral horizontal canal nerve caused conjugate eye movements, which was also observed in cats and other species by other investigators. 3. Stimulation of the unilateral vertical canal nerve caused a pattern of non-conjugate eye movements, which are different from those observed in cats. Such different patterns of vestibular eye movements in two different species are ascribable to the functional difference of the inferior and superior oblique muscles.