摘要:

AbstractA MEDLINE review suggested a lack of recent studies about the entrapments seen with underlying diabetic neuropathy. Suggested protocols for research in diabetic peripheral neuropathy have not included the concepts of entrapments as an early — indeed, first manifestation of the neuropathy. Carpal tunnel syndrome is a frequent accompaniment of diabetic peripheral neuropathy. Assessment of the degree of entrapment superimposed on the generalized peripheral neuropathy can be clarified by analysis of the CMAP and the SNAP — particularly with respect to duration of the negative spike of the action potential. Also, analysis of the action potentials elicited by stimulation of the ulnar and radial nerves and their comparison with the median nerve is often helpful. Finally careful inspection of the actions potential when stimulating proximal and distal to the entrapment will establish the degree of nerve compromise relative to the underlying diabetic neuropa

ISSN:0148-639X    

DOI:10.1002/mus.880160202

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractComparative effects of ischemia and acute hypoxemia (PaO2= 24 mm Hg) were studied in anesthetized cats on afferents from the tibialis anterior limb muscle. Metaboreceptors (groups III and IV fibers) and mechanoreceptors were identified by their activation by an intraarterial injection of lactic acid (LA) or high‐frequency vibrations (HFV) applied to the extremity of the muscle tendon, respectively. Ischemia and hypoxemia exerted opposite influences on the two categories of muscle afferents: they depressed the response of mechanoreceptors to HFV, but markedly enhanced the spontaneous tonic activity of metaboreceptors. The effects of hypoxamia were delayed but slightly greater and lasted longer during the recovery period than those exerted by ischemia. The inhibitory action on mechanoreceptors exerted by a reduced oxyden supply to muscle is interpreted as a result from local acidosis. Indeed, under normoxic conditions, a LA bolus injection during the HFV test also reduced the firing rate of these receptors. © 1993 John Wiley&Sons, I

ISSN:0148-639X    

DOI:10.1002/mus.880160203

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractFor the diagnosis of ocular myasthenia gravis (ocular MG), testing of the muscles close to the affected ones may be important. The relative importance of several methods: stimulated single fiber EMG (stimulated SFEMG), repetitive nerve stimulation test (RNS) of orbicularis oculi muscle, and infrared reflection oculography (IROG) was investigated. Thirty‐two patients in whom a diagnosis of ocular MG was considered on clinical grounds were admitted to the study. Based on the results of the three neurophysiological tests, the patients could be divided in three groups: a first group with an abnormal stimulated SFEMG, and an abnormal RNS and/or abnormal IROG; a second group with only a slightly abnormal stimulated SFEMG; and a third group with normal tests in all three tests. The clinical diagnosis of ocular MG was made in all 11 patients of the first group; in 86% (6 of 7) of the patients of the second group; and in 7% (1 of 14) of the patients of the third groups. This study demonstrates that the orbicularis oculi muscle is a suitable muscle for stimulated SFEMG in patients with ocular MG, and that the results obtained with this technique showed a better relation with the clinical diagnosis than those of the two other techniques. We also demonstrate that there is no additional value in studying the jitter with different stimulation rates in patients with suspected ocular MG. © 1993 John Wiley&Sons, I

ISSN:0148-639X    

DOI:10.1002/mus.880160204

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractPlasma carnitine “insufficiency,” (plasma esterified carnitine to free carnitine ratio above 0.25) was found in 21 48 (43.8%) patients with mitochondrial myopathy, of whom 4 also showed both total and free carnitine deficiencies in plasma. In addition, plasma levels of SCAC and LCAC were higher in patients with mitochondrial myopathy than in controls (P<0.001 andP<0.01, respectively). Patients diagnosed as having plasma carnitine insufficiency or deficiency were treated with L‐carnitine (50–200 mg/kg per day in four daily doses). Muscle weakness improved in 19 of 20 patients, failure to thrive in 4 of 8, encephalopathy in 1 of 9, and cardiomyopathy in 8 of 8 patients. Plasma carnitine “insufficiency” provides an additional clue to the diagnosis of mitochondrial myopathy and an indication for L‐carnitine therapy. © 1993 John W

ISSN:0148-639X    

DOI:10.1002/mus.880160205

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractWe studied 42 patients with cervical and lumbar radiculopathies using magnetic stimulation. Prolonged latencies following magnetic stimulation of the brain, the paravertebral spinal nerve, or both, showed a highly significant correlation with muscle weakness in clinical testing (24 of 26 patients with weakness had pathological motor evoked potentials) as well as with spontaneous activity of the target muscles in needle electromyography (24 of 25 subjects). The determination of both the central and the peripheral motor conduction time was found to be essential in patients with radiculopathies, because different patterns of latency changes correlated with different morphological results in computed tomography: in patients diagnosed as having a lateral compression of the nerve root the peripheral nerve latency was delayed; whereas, in patients with more medially localized herniations, a prolonged central motor latency was the most frequent finding. This study posits that combined magnetic stimulation of the brain and nerve root is an effective and painless technique for the noninvasive evaluation of nerve root function. © 1993 John Wiley&Sons, Inc

ISSN:0148-639X    

DOI:10.1002/mus.880160206

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractWe report a 53‐year‐old Jamaican man with 20 years of progressing weakness involving proximal limb muscles and neck flexors. Serum CK was 1100 IU/L. EMG demonstrated spontaneous activity, myopathic motor units, and full recruitment patterns in weak muscles. Muscle biopsy revealed marked myofiber degeneration with extensive fibrosis, suggesting a chronic myopathic process. HTLV‐1 antibody was present in serum in high titers by ELISA and Western blot. Immunohistochemistry with rabbit polyclonal antisera to HTLV‐1 showed rare staining myocytes. PCR demonstrated HTLV‐1 DNA in frozen muscle tissue. This myopathy, associated with HTLV‐1 infection, has clincal and pathological features similar to a dystrophy. We recommend serological screening for HTLV‐1 in cryptogenic adult myopathies. © 1993 John W

ISSN:0148-639X    

DOI:10.1002/mus.880160207

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractWe report electrophysiological findings of conduction along peripheral sensory fibers in 64 patients with amyotrophic lateral sclerosis. Distribution of the values of action potential amplitudes and conduction velocities of peripheral afferent fibers were significantly lower than in normal age‐matched controls. Sensory action potential amplitudes (SAPas) were more affected than sensory conduction velocities (SCVs). When single patients were considered, SAPas were slightly but significantly reduced in 22% of the cases (median nerve 17%, ulnar nerve 11%, and sural nerve 22%). A parallel decrease in SCVs and MCVs in 14 patients in whom the study was repeated over a period of time was also found. All these electrophysiological findings are due to progressive neuronopathy of peripheral sensory fibers. A pathogenetic mechanism is proposed. © 1993 John Wiley&Sons, I

ISSN:0148-639X    

DOI:10.1002/mus.880160208

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractWe report a patient who had six episodes of acute Guillain—Barre syndrome during his life. He is the fifth such case with postmortem analysis. © 1993 John Wiley&Sons, I

ISSN:0148-639X    

DOI:10.1002/mus.880160209

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractSix patients with a newly described genetic syndrome in Iraqi and Iranian Jews of congenital myasthenia associated with facial malformations were studied with voluntary and stimulation single fiber EMG (SFEMG). Voluntary SFEMG revealed abnormal jitter in all patients in both extensor digitorum communis (EDC) and orbicularis oculi (OOC) muscles, though much smaller in the clinically unaffected EDC. SFEMG study of OOC muscle by axonal stimulation at rates from 1 to 48 Hz showed the most increased jitter at the highest stimulation frequencies in the majority of end‐plates, one‐third of which showed maximal jitter at intermediate rates. These results may suggest a postsynaptic abnormality as the underlying cause for the neuromuscular transmission defect, and demonstrate the usefulness of SFEMG in the diagnosis of congenital myasthenia. © 1993 John Wiley&Sons,

ISSN:0148-639X    

DOI:10.1002/mus.880160210

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractWe studied low‐dose intramuscular succinylcholine in 9 subjects as part as an ongoing investigation of its potential to predict responses to botulinum toxin. We measured compound muscle action potentials (CMAPs) from the extensor digitorum brevis (EDB) muscles in each foot before and after intramuscular injections of 2.5 mg of succinylcholine into the EDB. Succinylcholine reduced mean CMAP amplitudes to 42% of baseline; the maximal reduction occurred at 19 ± 6 (mean standard deviation) minutes. Recovery to 73% of the baseline CMAP amplitude (approximately 50% recovery from block) occurred at 105 ± 49 minutes after injection. Repetitive (train‐of‐four) stimulation at 2 Hz produced mild CMAP decrements (5–25%), but only during the recovery phase. Varying the succinylcholine concentrations (10, 20, or 50 mg/mL) while holding the total drug dose constant did not change the rate of onset or the extent of block. No systemic complications occurred. We conclude that: (1) 2.5 mg intramuscular succinylcholine can safely induce selective muscle weakness with a time course that differs from intravenously administered succinylcholine; and (2) further clinical studies comparing intramuscular succinylcholine and botulinum toxin are warranted. © 1993 John Wiley

ISSN:0148-639X    

DOI:10.1002/mus.880160211

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY