• Title/Summary/Keyword: Conduction block

Search Result 95, Processing Time 0.029 seconds

A case of acute motor sensory axonal neuropathy presenting reversible conduction block

  • Lee, Dongah;Kim, Hyung Chan;Park, Kang Min;Park, Jinse;Ha, Sam Yeol;Kim, Sung Eun;Lee, Byung In;Kim, Jong Kuk;Yoon, Byeola;Shin, Kyong Jin
    • Annals of Clinical Neurophysiology
    • /
    • v.20 no.1
    • /
    • pp.49-52
    • /
    • 2018
  • Reversible conduction block (RCB) was rare in patients with acute motor sensory axonal neuropathy (AMSAN). A-46-year-old man presented with paresthesia, weakness, diplopia, and dysarthria. Nerve conduction study (NCS) exhibited axonal changes with conduction block in motor and sensory nerves. His symptoms were rapidly progressed and recovered. Conduction block was disappeared in the follow-up NCS performed after 2 weeks. The AMSAN case with RCB showed rapid progress and rapid recovery of clinical symptoms as acute motor axonal neuropathy patients with RCB.

Conduction Block of the Primary Afferent Fibers by Topically Applied Allyl Isotheocyanate

  • Shin, Hong-Kee;Kim, Kee-Soon
    • The Korean Journal of Physiology
    • /
    • v.28 no.2
    • /
    • pp.123-132
    • /
    • 1994
  • The present study was undertaken to elucidate the desensitization of cutaneous receptors and the conduction block of the afferent nerves induced by direct application of allyl isotheocyanate (mustard oil) to the receptive field (RF) or onto the afferent nerve, respectively. Dorsal horn cell responses to mechanical stimulations of RF were completely suppressed when mustard oil was applied to either the afferent nerve or the whole area of RF. C-fiber responses of dorsal horn cells were more susceptive to mustard oil than A-fiber activities. This was confirmed by the experiment in which the compound action potentials recorded from rat tibial nerve before and after topical application of mustard oil were compared. The higher the concentration of mustard oil and the longer the application time, the more powerful desensitization or conduction block was induced. From the results of the present study, it is suggested that the desensitization of the afferent fiber and sensory receptors induced by mustard oil results mainly from the conduction block of C-fiber in the primary afferent nerve.

  • PDF

A Case of Acute Motor Conduction Block Neuropathy Associated with Anti-GM1 Antibody (GM1 항체와 연관된 급성 운동 전도차단 신경병증 1예)

  • Park, Kang-Min;Bae, Jong-Seok;Kim, Sang-Jin;Lee, Jeong-Nyeo;Kim, Jong-Kuk
    • Annals of Clinical Neurophysiology
    • /
    • v.9 no.2
    • /
    • pp.89-92
    • /
    • 2007
  • A 33-year-old women developed weakness in all limbs 3 days prior to admission. Motor examination showed decreased strength in all limbs, but sensory examination was normal. Deep tendon reflexes were areflexia. Electrophysiological examination showed conduction blocks with nearly normal conduction velocities and terminal latencies in motor nerves and normal amplitudes and velocities in sensory nerves. Her serum was positive for IgG antibodies to gangliosides GM1, GD1b, and galactocerebroside. Acute motor conduction block neuropathy may be another variant of Guillain-Barre syndrome.

  • PDF

A Case of Lewis-Sumner Syndrome Improved by Oral Steroid Therapy (경구 스테로이드 치료로 호전된 Lewis-Sumner 증후군 1예)

  • Kim, Jong Kuk;Kim, Min-Jeong;Yoo, Bong-Goo;Kim, Kwang-Soo;Lim, Kwon Il
    • Annals of Clinical Neurophysiology
    • /
    • v.8 no.1
    • /
    • pp.102-105
    • /
    • 2006
  • We present a case with stepwise weakness and sensory involvement of both hands for more than 2 months. His nerve conduction study findings revealed prolonged terminal latencies, decreased motor and sensory conduction velocities and conduction blocks of both ulnar nerves, more severely on left side. And there were other abnormalities manifested with mononeuropathy multiplex. Increased cerebrospinal fluid protein was found. We diagnosed him as Lewis-Sumner syndrome and tried high dose oral steroid therapy for 2 months. He showed improvement of motor functioning with persistent conduction block.

  • PDF

Analysis of heat conduction of cylinder block of turbocharged gasoline engine by boundary element method (경계요소법에 의한 터보과급 가솔린기관 실린더블럭의 열전도 해석)

  • 김은태;최영돈;홍진관
    • Journal of the korean Society of Automotive Engineers
    • /
    • v.11 no.2
    • /
    • pp.41-54
    • /
    • 1989
  • In this study, steady state heat conduction problems of the cylinder block of turbocharged gasoline engine were solved by the boundary element method. Surface of the cylinder block was divided by the triangular cells with constant potential. Temperature distribution, effective heat transfer coefficient of the cylinder block were investigated with variation of equivalence ratio, engine speed and boost pressure. The results show that maximum temperature of cylinder block increase rapidly with increasing engine speed and boost pressure. The monolithic structure of cylinder block results in sever inhomogeneity of inner wall temperature at the high engine speed and boost pressure.

  • PDF

Multifocal Motor Neuropathy (다초점성 운동신경병증)

  • Lee, Dong-Kuck
    • Annals of Clinical Neurophysiology
    • /
    • v.4 no.2
    • /
    • pp.98-107
    • /
    • 2002
  • Multifocal motor neuropathy (MMN) is a chronic immune-mediated peripheral myelinopathy. The major clinical features include slowly progressive, painless, and asymmetric weakness, usually of distal limb muscle. Early in the course of the disease, weakness is not necessarily associated with muscle atrophy, owing to the initial primary involvement of peripheral myelin. Chronic progressive weakness is often associated with some degree of concurrent axonal loss and subsequent muscle atrophy. Sensory symptoms are usually mild or absent, and involvement of cranial and respiratory muscles is rare. The findings of multifocal motor conduction block, abnormal temporal dispersion, and focal conduction slowing at segments not at risk for common entrapment or compression injury, associated with normal sensory conduction studies along the same segments, are the hallmark electrophysiologic features of MMN. The slow progression and absence of upper motor neuron signs are the major clinical points that separate MMN from amyotrophic lateral sclerosis. The role of GM1 antibodies, found in high titers in 22~84% of MMN patients, remains uncertain. The contention that MMN is an autoimmune disorder is largely based on the often dramatic improvement in symptoms following the administration of intravenuos immunoglobulin or cyclophosphamide.

  • PDF

Study on the Thermal Stress Distribution Characteristivs of the Cylinder Block of a Light Gasoline Engine (경차용 가솔린 기관 실린더 블럭의 열응력 분포 특성에 대한 연구)

  • 김병탁
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.22 no.6
    • /
    • pp.800-808
    • /
    • 1998
  • In this study the thermal stress distribution and deformantion characteristics resulting from the nonuniform temperature fields of the cylinder block of a light 3-cylinder 4-stroke gasoline engine were analyzed using the 3-dimensional finite element method. The temperature distributions req-uisite for the thermoelastic behavior alalysis were obtained from the steady-state heat conduction analysis performed on the basis of experimental data. in order to examine the effect of a ceramic material the cylinder liner was replaced by the silicon nitride($Si_{3}N_{4}$) and its thermal behaviors were compared with those of the original block.

  • PDF

Conjugate Heat Transfer in a Vertical Channel with Protrunding Heat Source (돌출된 열원이 부착된 수직 채널내 복합열전달)

  • Kim, Ui-Gwang;Baek, Byeong-Jun;Jo, Byeong-Su
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.20 no.2
    • /
    • pp.741-751
    • /
    • 1996
  • The coupled conduction and convection heat transfer from the protruding heat source in a vertical channel is numerically investigated. Conjugate solution of the two-dimensional energy equation is obtained for the incompressible air flow over the rectangular block with local heat source. It was found that several recirculation zones and separation bubble near the block were related to Re and Gr. And the results show that fractions of the heat transfer through each of the block face, maximum temperature of the block and the relative effect of each parameter on the maximum temperature and heat transfer.

Electrophysiological Features of Diabetic Polyneuropathy: Motor Nerve Conduction Studies (당뇨병성다발신경병증의 전기생리학적 특징: 운동신경전도검사)

  • Kang, Ji-Hyuk;Lee, Yun-Seob
    • The Journal of the Korea Contents Association
    • /
    • v.10 no.10
    • /
    • pp.237-245
    • /
    • 2010
  • Nerve conduction studies (NCS) are the most objective measure of nerve function and essential for the diagnosis of sub-clinical neuropathy in diabetes mellitus and diabetic polyneuropathy (DPN). This study evaluates the characteristic of electrophysiological abnormalities in DPN. Electrodiagnostic data from 120 patients with diabetic polyneuropathies and 77 control subjects were reviewed. Motor nerve conduction velocities (MNCV), distal motor latencies (DML), compound muscle action potential (CMAP) amplitudes, No potential frequency and conduction block were analyzed. Data were normalized based on normative reference values, and the proportion of nerves with abnormal values in the lower and upper limbs were evaluated. DPN was systemic demyelinating peripheral polyneuropathy and more severe abnormal nerve conduction was found in lower limbs than in upper limbs. The abnormal degree was more severe in peroneal nerve. It was no statistically significant difference of conduction block in control and DPN group. Our findings suggest that DPN had more common and severe peroneal nerve involvement in the motor nerve conduction studies (MNCS). These findings have important implications for the electrophysiological evaluation of DPN.

Study on the Steady-State Heat Conduction Characteristics of a Small Gasoline Engine (소형 가솔린 기관의 정상 열전도 특성에 관한 연구)

  • 김병탁
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.21 no.3
    • /
    • pp.267-277
    • /
    • 1997
  • In this paper, heat conduction characteristics of the cylinder block of a small 3 - cylinder, 4¬stroke gasoline engine were analyzed using the 3 - dimensional finite element method. Based on the experimental data, the engine cycle simulation was carried out in order to obtain the heat transfer coefficient and the temperature of the gas and the mean heat transfer coefficient of the coolant. Heat transfer data of the gas, which were averaged with respect to exposure time to the wall, were taken as convective boundary conditions corresponding to the operating conditions to obtain the temperature fields of the block. Finally silicon nitride(Si3N4) was taken as the material of the block liner in order to investigate its temperature distribution characteristics and compare the results with the original ones.

  • PDF