• Journal of the Korean Academy of Clinical Electrophysiology
• /
• v.4 no.1
• /
• pp.63-83
• /
• 2006

This study conducted the following experiment to examine anesthetic effects of 500 kHz ultrasound with lidocaine. Clinical experiment was conducted to compare local anesthetic effects by ultrasound frequencies and drugs with 40 normal adults and it divided subjects into experimental group (I) applying only ultrasound, ointment group (II) applying only lidocaine, phonophoresis group of 1 MHz (III), phonophoresis group of 500 kHz lidocaine (IV) for pain threshold and nerve conduct experiments. Mechanical threshold was measured with von Frey monofilament, thermal pain threshold with halogen lamp and digital thermometer, action potential in median nerve with diagnostic electromyography before and after treatment, and at 30 min., 60 min., 90 min., and 120 min. after treatment. Results of this study can be summarized as follows. Topical anesthesia experiment showed that pain threshold of phonophoresis groups was significantly increased, but there were little differences in ultrasound frequency and drugs among phonophoresis groups. Conduction anesthesia experiment showed that phonophoresis group of 500 kHz using lidocaine had significant difference in pain threshold and sensory nerve conduction compared to ointment group and ultrasound group, but there was no great difference from other phonophresis groups and light nerve block effect was found. It was considered that application of 500 kHz ultrasound using lidocaine will be more effective in deep anesthesia or nerve block than 1 MHz ultrasound. However, researches considering various frequencies, intensities and application hours in low frequency areas including kHz ultrasound are needed to increase deep permeation of drugs.

• Annals of Clinical Neurophysiology
• /
• v.16 no.1
• /
• pp.8-14
• /
• 2014

Background: Early detection of neuropathy may prevent further progression of this complication in the diabetic patients. The purpose of this study was to evaluate the prevalence of early neuropathic complication in patients with newly diagnosed type 1 and type 2 diabetes. Methods: Nerve conduction studies (median, ulnar, posterior tibial, peroneal, and sural nerves) were performed for 49 type 1 (27 males, mean $14.1{\pm}7.5$ years) and 40 type 2 (27 males, $42.0{\pm}14.1$ years) diabetic patients at onset of diabetes. Children with age at onset under 4 years and adults over 55 years were excluded to eliminate the aging effect and the influence of obstructive arteriosclerosis. Neuropathy was defined as abnormal nerve conduction findings in two or more nerves including the sural nerve. Results: Mean HbA1c level was $12.6{\pm}3.3%$ for type 1 and $10.5{\pm}2.9%$ for type 2 diabetes. The prevalence of neuropathy was 12.2% for type 1, and 35.0% for type 2 diabetes, respectively. There were significant trends in the prevalence of neuropathy with increasing age (p<0.05). The effect of the mean level of glycosylated hemoglobin on the prevalence of polyneuropathy at onset of diabetes was borderline (p=0.0532). Neither sex of the patients nor the type of diabetes affected the neurophysiologic abnormalities at the diagnosis. Conclusions: Even in a population with diabetes at the diagnosis, the prevalence of subclinical neuropathy was not low. Neuropathy has been significantly associated with increasing age indicating the possibility of longer duration of undetected diabetes among them, especially in type 2 diabetes.

• Annals of Clinical Neurophysiology
• /
• v.3 no.2
• /
• pp.156-159
• /
• 2001

Miller Fisher syndrome(MFS) has been the focus of conflicting opinions regarding the peripheral versus the central nature of the site of major neural injury. We present our electrophysiological findings in one case of MFS to help clarify the pattern of peripheral nerve injury in this syndrome. A 45-year-old man visited our hospital due to sudden diplopia. Initial examination revealed internuclear opthalmoplegia. The next day, his symptoms rapidly aggravated to complete external ophthalmoplegia, ataxia, and areflexia with hand and foot numbness. Serial electrophysiological studies were performed. The results of brainstem evoked potential(BAEP) and blink reflex were normal in the serial studies. Motor and sensory nerve conduction study(NCS) were normal findings in second hospital day, but ulnar sensory nerve shows no sensory nerve action potential(SNAP) and sural sensory conduction velocity was delayed in 7th hospital day. Our patient's clinical presentation began to improve on 15th hospital day, and his electrophysiologic study showed improvement on 29th hospital day. We believe that all the manifestations of MFS can be explained by the involvement of peripheral nerves without brainstem or cerebellar lesion with the serial electrophysiological studies.

• Annals of Clinical Neurophysiology
• /
• v.19 no.2
• /
• pp.125-130
• /
• 2017

Background: Routine nerve conduction study (NCS) can only be used to evaluate the function of large fibers, and the results of NCS are often normal in patients with distal sensory polyneuropathy. The measurement of the current perception threshold (CPT) has been reported to represent a variety of peripheral nerve fiber functions. This study was performed to investigate the value of measuring CPT in patients with diabetic sensory polyneuropathy who have no abnormalities in routine NCS. Methods: Twenty-seven diabetic patients with sensory polyneuropathy and normal routine NCS and 18 age-matched control subjects participated in this study. The CPT was measured on the unilateral index finger and great toe of each subject at frequencies of 5 Hz, 250 Hz, and 2,000 Hz. Results: CPT values were significantly higher in the patient group than in the control group, especially with stimuli at the lowest frequency of 5 Hz (p < 0.05). There were significant correlations between the CPT values obtained at three different frequencies in the patient group, whereas the correlation was only significant in the pair of 250 Hz/5 Hz (both in the hands and feet), and in the pair of 2,000 Hz/250 Hz (in the feet) for the control group. Conclusions: Our data suggest that the CPT test, especially at a stimuli frequency of 5 Hz, may be a useful screening tool for diabetic polyneuropathy in patients who show no abnormalities in routine NCS.

• Journal of Yeungnam Medical Science
• /
• v.8 no.1
• /
• pp.79-85
• /
• 1991

The author studied 20 healthy adults (20 hands) as a control and 30 patients (40 hands) with carpal tunnel syndrome to evaluate the clinical usefulness of measuring nerve conduction velocity after wrist fiexion in diagnosis of carpal tunnel syndrome. The median nerve conduction velocity over wrist to finger segment was measured before and after wrist flexion for 1, 2 and 5 minutes, using belly-tendon method for motor nerve distal latency(MNDL) and antidromic method for sensory nerve conduction velocity(SNCV). The results were as follows : 1. In control froup, MNDL increased in 1 hand and SNCV decreased in 2 hands after wrist flexion. In patient group, MNDL increased in 2 hands and SNCV decreased in 3 hands after wrist flexion. 2. In both control and patient group, there were no significant changes in mean values of SNCV and MNDL between before and after wrist flexion. 3. Phalen's wrist flexion test was positive in 5 percent of control and 60 percent of patient group. 4. Tinel's sign was present in 10 percent of control and 33 percent of patient group.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.10
• /
• pp.290-298
• /
• 2017

This study compared the median nerve, ulnar never, and F waves of patients diagnosed with early Carpal Tunnel Syndrome to a control group to determine whether F waves could be a useful indicator in the diagnosis of early CTS. The terminal motor latency (TML), terminal motor amplitude and sensory nerve conduction velocity (SNCV) of the section from the palms to the wrists, which are the key indicators to use in a nerve conduction study, and F waves were compared with the control group using the t-test. A correlation analysis was performed to analyze the correlation between the main indicators. The comparison between the median nerve's TML of the early CTS patients and that of the control group shows that there are 2 sections which have high significance (p<0.001). In the comparison of the SNCV of the median nerve between the control group and early CTS patients, high significance was observed (p<0.001). In the analysis of the F waves, there was high significance (p<0.001) between the control group and early CTS patients for the median nerve, but not for the ulnar nerve. The correlation analysis revealed that both the SNCV-TML and F wave-TML had significance. These results suggested that, along with TML and SNCV, F waves can be a useful indicator to diagnose CTS.

• Journal of Oral Medicine and Pain
• /
• v.30 no.4
• /
• pp.447-455
• /
• 2005

The purpose of this study was to examine the effect of Nd:YAG laser irradiation for sensory nerve conduction change. Nd:YAG laser was irradiated to mental region for 5 minutes with the parameters that 10 Hz and 20 Hz of 100 mJ/pulse. Target size of irradiation was 30 mm diameter of circle and target-tip distance was about 10 mm. Therefore, the power density were 212 $mW/cm^2$ and 424 $mW/cm^2$. Sensory nerve conduction was evaluated with $Neurometer^{\circled}$ CPT/C before and after Nd:YAG laser irradiation. As an outcomes, the current perception threshold(CPT) and pain tolerance threshold(PTT) were obtained. We made a comparison of these two values and the results were as follows. 1. There was no significant difference in CPT at 1W, 10 Hz and 2 W, 20 Hz Nd:YAG laser irradiation. 2. There was no significant difference in PTT at 10 Hz, 20 Hz of 100 mJ/pulse Nd:YAG laser. 3. There were no significant differences in CPT and PTT between 1 W, 10 Hz group and 2 W, 20 Hz group. Therefore, We can make a conclusion that Nd:YAG laser irradiation to mental region have no effect on mental nerve conduction in our study model.

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

• Kosin Medical Journal
• /
• v.33 no.2
• /
• pp.257-262
• /
• 2018

Guillain-$Barr{\acute{e}}$ syndrome (GBS) and acute disseminated encephalomyelitis (ADEM) are demyelinating neurologic disorders with different target organs. Although they share similar pathogenetic mechanism, reports of simultaneous occurrence of the 2 disorders are rare. A 2 year 6 month old girl visited our hospital for fever, cough, and general weakness. Although the muscle power of extremities showed mild weakness and voiding difficulty, initial deep tendon reflex of both knees and ankles was normal. A nerve conduction study to evaluate the weakness revealed the absence of F waves. Cerebrospinal fluid analysis demonstrated pleocytosis with lymphocyte predominance and elevated protein levels. Magnetic resonance imaging showed abnormal T2 hyperintensity in pons, medulla and spinal cord. Serum anti-GD1b antibody was positive. Based on clinical findings, laboratory findings, nerve conduction study, and neuroimaging, the diagnosis of GBS and ADEM was made. This is the first case of GBS accompanied by ADEM in Korea.

• Annals of Clinical Neurophysiology
• /
• v.4 no.2
• /
• pp.125-132
• /
• 2002

Objectives : Although the diagnosis of hereditary neuropathy with liability to pressure palsies (HNPP) is important for correct prognostic evaluation and genetic counseling, the diagnosis is frequently missed or delayed. Our main aim on undertaking this study was to characterize the electrodiagnostic features of HNPP. Material and Methods : Clinical, electrophysiologic and molecular studies were performed on Korean HNPP patients with 17p11.2 deletion. The results of electrophysiologic studies were compared with those of Charcot-Marie-Tooth disease type 1A (CMT1A) patients carrying 17p11.2 duplication. Results : Eight HNPP (50 motor, 39 sensory nerves) and six CMT1A (28 motor, 16 sensory nerves) patients were included. The slowing of sensory conduction in nearly all nerves and the distal accentuation of motor conduction abnormalities are the main features of background polyneuropathy in HNPP. In contrast to CMT1A, where severity of nerve conduction slowing was not different among nerve groups, HNPP sensory nerve conduction was more slowed in the median and ulnar nerves than in the sural nerve (p<0.01), and DML was more prolonged in the median nerve than in the other motor nerves (p<0.01). TLIs were significantly lower in HNPP than in the normal control and CMT1A patients for the median and ulnar nerves (p<0.01), and were also significantly reduced for the peroneal nerve (p<0.05) compared with those of the normal controls. Conclusion : The distribution and severity of the background electrophysiologic abnormalities are closely related to the topography of common entrapment or compression sites, which suggests the possible pathogenetic role of subclinical pressure injury at these sites in the development of the distinct background polyneuropathy in HNPP.