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PubMedDate not supplied

[Neuroleptic malignant syndrome and related conditions].

Neuroleptic malignant syndrome is characterised by muscular rigidity, fever and signs of severe vegetative nervous system involvement. Its etiopathogenesis is still unclear and the disease is potentially fatal. Its clinical aspects, which are often only partially manifested, make it difficult to formulate a correct diagnosis in time, not least due to the problem of differential diagnosis with other syndromes with similar symptoms but a different pathogenesis, psychopathology and therapy: acute lethal catatonia, fatal acute delirium, heat-stroke, malignant hyperthermia. The speed of the diagnosis is vital for effective therapy, but this is made even more difficult by the need approach. The paper presents eleven case studies; after an analysis of the numerous clinical aspects of the syndrome and the definition of its diagnostic parameters, an appropriate therapeutic protocol is outlined. Lastly, the problem of retreatment using a neuroleptic of the same or a different class is discussed once the acute phase has been overcome.

Amantadine↗
PubMed2005

[A 67-year-old man with rt. hand resting tremor and rigidity after lt. putaminal hemorrhage].

We report a 67-year-old man with rt. hand resting tremor and rigidity after lt. putaminal hemorrhage. He had hypertension and alcoholic liver cirrhosis as past history. When he was 62 years old, he realized rt. hemiplegia suddenly and admitted in Juntendo Urayasu hospital. Brain CT showed intracranial hemorrhage in lt. putamen. He was treated with neurosurgery operation for rejecting hemorrhage. Mild rt. hemiparesis remained but he could live independently. He was medicated sulpiride for depression after cerebrovascular accident. On 63 years old, resting tremor and rigidity appeared on his rt. hand. His doctor stopped sulpiride and treated with L-Dopa/Benserazide and trihexiphenidyl. His parkinsonism was stable with this treatment for four years. His doctor considered that he was Parkinson's disease or drug-induced parkinsonism. On 67 years old, he became akinetic-mutism state suddenly and admitted in the hospital. His consciousness turned alert soon and discharged after two weeks. This episode was considered as epilepsy. After one week from discharge, he was found cardio-pulmonary arrest and confirmed dead in the hospital. Post-mortem examination revealed necrosis in the posterior-lateral part of lt. putamen due to hemorrhage. However, there was no degenerative change of the striatum or the substantia nigra and no Lewy bodies in his brain. Other pathological changes were also not found. His parkinsonism might be caused putaminal pathology due to hemorrhage.

Aged↗
PubMed1998

Gait disorder and parkinsonian signs in patients with stroke related to small deep infarcts and white matter lesions.

Vascular parkinsonism is thought to be a distinct parkinsonian syndrome associated with small deep infarcts and white matter lesions (WMLs). We studied the prevalence of parkinsonian features (bradykinesia, rigidity, tremor, and gait disorder) in relation to small deep or territorial infarcts and WMLs on computed tomography (CT) in 62 lacunar and 41 territorial stroke patients, at 3.0 (median) years of follow up. One or more parkinsonian signs were found in 36% of these patients; 11% clinically had parkinsonism. Parkinsonian signs were found more frequently in lacunar than in territorial stroke patients: bradykinesia in 45% and 7%, rigidity in 13% and 7%, tremor in 6% and 7%, and gait disorder in 16% and 7%, respectively. Patients with WMLs at study entry (n = 16) were compared with those without WMLs (n = 87): 56% and 25% had bradykinesia, 25% and 8% rigidity, 25% and 3% tremor, and 38% and 8% gait disorder, respectively. Regression analysis with adjusted odds ratios ([a]OR) showed that WMLs at study entry were associated with bradykinesia ([a]OR 8.0, 95% confidence interval [CI] 1.6-41.6), gait disorder ([a]OR 7.1, 95% CI 1.5-33.7), and tremor ([a]OR 7.0, 95% CI 1.2-40.3). Bradykinesia was associated with lacunar stroke at study entry ([a]OR 11.5, 95% CI 2.4-54.9). Thus, one third of our stroke patients had one or more parkinsonian signs, and 10% clinically had a parkinsonian syndrome that differed from Lewy body parkinsonism: infrequent resting tremor, but frequent gait disorder. Parkinsonian signs were associated with WMLs and lacunar stroke. Therefore, this study favors a distinct vascular parkinsonian syndrome.

Adult↗
PubMed2000

[Deep brain stimulation(DBS) therapy for parkkinson,s disease].

During the last decade, it has become increasingly clear that DBS represents a useful adjunct for therapies to control various symptoms of Parkinson's disease. The stimulation sites include the thalamic nucleus ventralis intermedius(Vim), globus pallidus internus(GPi) and subthalamic nucleus (STN). The clinical data of DBS therapy currently available from the literature, together with our own experience, are reviewed. The results of our double blinded evaluation of the effects of GPi and STN stimulation are also summarized. DBS therapy affords the best effect on tremor when the Vim is selected as the stimulation site. DBS therapy is also useful for controlling rigidity when the GPi or STN is stimulated. Improvement of bradykinesia may often be induced by DBS therapy involving the GPi or STN. Dopa-induced dyskinesia can be attenuated effectively by the direct and/or indirect effects of DBS therapy. Two advantages of GPi and STN stimulation were identified in our double blinded evaluation. Firstly, the stimulation can supplement a reduced action of levodopa during the off-period. It thus improves the patient's daily activities through attenuation of the motor fluctuations. Secondly, the stimulation can replace part of the action of levodopa during the on-period. It thus attenuates dopa-induced dyskinesia through a reduced dose of medication. More importantly, the stimulation improves the daily activities in dopa-intolerant patients who are being administered a small dose of levodopa because of unbearable side effects. In addition, GPi stimulation has its own inhibitory effect on dopa-induced dyskinesia.

Clinical Trials as Topic↗
PubMed1982

The neuroleptic malignant syndrome.

The neuroleptic malignant syndrome (NMS) comprises hyperpyrexia, altered consciousness, muscular rigidity, and autonomic dysfunction. It is a rare idiosyncratic reaction to major tranquilizers, including the phenothiazines, butyrophenones, and thioxanthenes; haloperidol and fluphenazine enanthate or fluphenazine decanoate are the drugs most commonly incriminated. The syndrome occurs after therapeutic rather than toxic doses of neuroleptic drugs and is unrelated to the duration of therapy. The NMS is attributed to a disturbance of dopaminergic systems within the basal ganglia and hypothalamus. Associated laboratory abnormalities include leukocytosis, with elevated serum creatine phosphokinase (CPK) and liver enzyme concentrations. The NMS, which is known to some psychiatrists and neurologists but to few internists, probably is underdiagnosed; therefore, its true incidence is unknown. The NMS should be included in the differential diagnosis of any febrile patient with a history of neuroleptic treatment. Because the mortality of NMS is about 20%, early diagnosis and withdrawal of the neuroleptic drug therapy is crucial. Supportive treatment in a medical intensive care unit may be required.

Antipsychotic Agents↗
PubMed2005

Monoaminergic drugs and directly observable signs of LAAM withdrawal in rhesus monkeys.

Monoaminergic ligands modified a naltrexone discriminative stimulus in rhesus monkeys dependent on 2 mg/kg per day of the mu opioid L-alpha-acetylmethadol (LAAM). This study examined a role for monoamines in the directly observable and physiologic manifestations of LAAM withdrawal induced by naltrexone in the same monkeys. The effects of saline, clonidine (0.032 mg/kg), haloperidol (0.032 mg/kg), cocaine (1.0 mg/kg), amphetamine (1.0 mg/kg) and imipramine (10.0 mg/kg) were examined in LAAM-dependent monkeys that subsequently received saline or naltrexone (0.0001-1.0 mg/kg). Naltrexone dose-dependently increased respiration, abdominal rigidity and salivation. Clonidine attenuated each of these withdrawal signs, whereas haloperidol increased some (i.e. respiration) and decreased others (i.e. salivation). When administered alone, cocaine and amphetamine increased respiration and also increased the respiratory stimulant effects of naltrexone; cocaine and amphetamine did not attenuate any measure of withdrawal. With the exception of a decrease in naltrexone-induced salivation, imipramine was without effect. These results are strikingly different from results in these same LAAM-dependent monkeys showing that cocaine and amphetamine, but not clonidine, markedly attenuated a naltrexone discriminative stimulus. That monoaminergic ligands differentially alter the directly observable and discriminative stimulus effects of naltrexone in LAAM-dependent monkeys supports the view that monoamines differentially mediate the physical manifestations (norepinephrine) and subjective experience (dopamine) of opioid withdrawal.

Adrenergic alpha-Agonists↗
PubMed1994

The syndrome of 'pure akinesia' and its relationship to progressive supranuclear palsy.

Five patients developed a stereotyped syndrome of progressive akinesia of gait, speech, and hand-writing without rigidity, tremor, or dementia. The symptoms did not improve with levodopa. These clinical findings conform to a syndrome described repeatedly in Japan since 1974 as "pure akinesia." Evidence has indicated that pure akinesia often represents a pre-ocular motor, and in some cases an ocular motor-sparing, form of progressive supranuclear palsy (PSP). Although we found disorders of eyelid movements, none of the patients demonstrated a gaze palsy on clinical examination. Four patients underwent eye movement recordings. The two patients with the longest disease duration had slow or small vertical saccades. These findings support the notion that patients with pure akinesia may develop a vertical gaze palsy, similar to that in PSP, late in their course. Our patients show that pure akinesia occurs in North America as well as in Japan. Recognition of the syndrome of pure akinesia may suggest the diagnosis of PSP before the development of abnormalities of ocular movement.

Dementia↗
PubMed1986

Plasma haloperidol levels drawn at neuroleptic threshold doses: a pilot study.

The daily haloperidol doses of 33 newly admitted, acutely psychotic schizophrenic patients were rapidly adjusted to a point at which slight hypokinesia-rigidity first appeared on clinical examination (the neuroleptic threshold). The mean daily haloperidol dose at which the neuroleptic threshold was crossed was 4.2 +/- 2.4 mg/day. The plasma haloperidol levels obtained at these neuroleptic threshold doses clustered around a mean of 4.9 +/- 2.9 ng/ml. This plasma haloperidol level distribution extensively overlaps the proposed lower boundaries for the therapeutically effective range of plasma haloperidol levels, but it is below the range in which coarse extrapyramidal side effects appear in high frequency (greater than 10 ng/ml). Sixty-seven percent of our patients demonstrated moderate or greater therapeutic improvement within 3 weeks of treatment at neuroleptic threshold doses, a therapeutic efficacy rate identical to that expected with standard neuroleptic doses. The authors propose that the neuroleptic threshold is a readily available clinical marker which identifies a range of plasma haloperidol levels capable of producing therapeutic response with minimal associated coarse extrapyramidal side effects.

Adolescent↗
PubMed1979

[Effects of diazepam and baclofen on the anemic decerebrate rigidity in rats (author's transl)].

Effects of diazepam and baclofen on the anemic decerebrate rigidity in rats were studied by using the drugs that modify GABAergic mechanisms of deplete catecholamine. Rigid forelimb tension in anemic decerebrate rats took the form of tonically sustained tension (tonic component), while the phasic tension (phasic component) was induced by mechanical stimulation of hindlimbs. Diazepam exerted a marked dose-dependent inhibition of the phasic component, whereas baclofen produced a similar effect on both tonic and phasic components. In rats pretreated with semicarbazide, the inhibitory effect of diazepam on phasic component was reduced, and the effect of semicarbazide was antagonized by pyridoxine. The effect of diazepam was slightly enhanced by pretreatment with aminooxyacetic acid, and antagonized by picrotoxin. In contrast to diazepam, the depressant actions of baclofen on both components were not affected by semicarbazide, aminooxyacetic acid or picrotoxin. Catecholamine depletion produced by alpha-methyltyrosine or disulfiram significantly reduced the effect of baclofen on the phasic component. It thus appears that GABA is involved in the effect of diazepam on the phasic component, and noradrenaline is involved in the same effect of baclofen in anemic decerebrate rats.

Aminooxyacetic Acid↗
PubMed2005

Unilateral stereotactic posteroventral globus pallidus internus pallidotomy for Parkinson's disease: surgical techniques and 2-year follow-up.

With the advent of levodopa (L-dopa) and the recognition of its striking effect on Parkinson's disease (PD), virtually all surgical procedures for PD ceased from the mid 1960s. However, there has been a resurgence of pallidotomy and other stereotactic procedures in the last two decades as physicians realized that most PD patients eventually face medical failure after long-term treatment with L-dopa. Nine PD patients, three men and six women, with an average age of 62 years and disease duration of 13 years underwent unilateral globus pallidus internus (GPi) pallidotomy contralateral to the side with marked akinetic symptoms and drug-induced dyskinesia. All patients were evaluated using the Unified Parkinson's disease Rating Scale (UPDRS) after drug withdrawal and while taking their optimal medical regimen, preoperatively and 6, 12, and 24 months after surgery. There was significant improvement in activities of daily living and motor subscores as well as total UPDRS score in the "off" state at the 2-year follow-up, which mainly resulted from improvement in contralateral bradykinesia and rigidity. Significant improvements in contralateral akinetic symptoms and drug-induced dyskinesia were also observed in the "on" state and were sustained for at least 2 years. Ipsilateral and axial symptoms were not altered by unilateral GPi pallidotomy. The complications of surgery were generally well tolerated. One patient had a small postoperative asymptomatic hemorrhage identified by routine follow-up magnetic resonance imaging. Another two patients developed temporary sexual disinhibition and auditory hallucination, respectively, which resolved spontaneously 2 weeks after surgery. The effect of pallidotomy for alleviation of akinetic parkinsonism is modest but significant, and continues to be effective for at least 2 years. Further analytical studies, especially the correlation of clinical effects and lesion locations, are important not only to provide direct feedback for surgeons to examine the technical accuracy and but also to facilitate understanding of the pathophysiology of PD.

Activities of Daily Living↗
PubMed2004

L-DOPA reverses the hypokinetic behaviour and rigidity in rotenone-treated rats.

Peripherally and locally administered rotenone (an inhibitor of mitochondrial complex I) has been proposed as a model of Parkinson's disease (PD) as it induces nigrostriatal degeneration associated with alpha-synuclein inclusions. If rotenone-induced symptoms represent a model of PD, than they should be counteracted by L-DOPA. To answer this question, rats were treated with rotenone 2.5 mg/kg over 48 days. Behavioural data showed a strong increase in catalepsy, a decrease in locomotor activity and biochemical data showed a significant depletion of dopamine levels in the striatum (Cpu) and substantia nigra in rotenone treated animals compared to vehicle. To examine the effectiveness of L-DOPA in reversing the motor deficit in rats, a dose of L-DOPA (10 mg/kg) in combination with the peripheral amino acid decarboxylase inhibitor benserazide were daily administrated intraperitonially for a period of 10 days in the rotenone-treated rats. This treatment counteracted catalepsy and increased locomotor activity and number of rearings but decreased inactive sitting. In this animal model (rotenone model), catalepsy tests and motor activities showed that the clinically used anti-parkinsonian drug L-DOPA substitutes rotenone-induced dopamine (DA) deficiency.

Animals↗
PubMed1985

[Clinical neurophysiology in the evaluation and physiopathology of Parkinson's disease].

Clinical Neurophysiology brings about 2 major contributions in the study of Parkinson's disease: on the one hand, it makes it possible to measure the motor troubles; on the other, it enables their pathophysiological analysis. The 3 classical signs must be studied separately. Tremor can easily be recorded by electromyography. Moreover, its parkinsonian nature can be specified by studying the resetting of EMG bursts following electrical stimulation of the motor nerve. A pace maker has been demonstrated in the thalamus from where rhythmic messages are first sent to motor cortex and thereafter reverberated to spinal motoneurons. Rigidity can be assessed by sophisticated but not generalized methods. It is easier to evaluate it by long-loop responses evoked by proprioceptive or exteroceptive stimulations. These responses reflect activity in pathways relaying in supraspinal structures. Contrary to spasticity, rigidity is not basically due to dysfunctions in segmentary spinal circuits. It is more likely that it depends on hyperactive and hyperexcitable long loop pathways. This hypothesis is in agreement with well established facts showing that parkinsonian hypertonia vanishes after dorsal root section. Akinesia is complex semeiologically. It is made of various components some of which can be measured. Reaction times and movement times provide interesting data which however are not strictly correlated with the motor handicap. Motor programmes are assembled in normal delays but they are not "called upon" correctly, reflecting a disturbance in the motor planning. A lack of "energetization" of the motor cortex and the pyramidal tract is likely. A functional disconnection between the motor program/plan side and the execution side can be hypothesized to explain the 3 major signs; on the one hand, neural messages are not correctly transferred to the pyramidal system, on the other, spinoencephalospinal loops on the execution side become more active as they escape from the control normally exerted by the plan/program side where basal ganglia play a prominent role.

Animals↗
PubMedDate not supplied

[Spinal cord paraneoplastic syndromes].

OBJECTIVE: We reviewed the bibliography of various paraneoplastic syndromes which may show spinal involvement. DEVELOPMENT: Paraneoplastic sensory neuropathy, myelitis and rigidity syndromes may present alone or as part of a generalized syndrome of paraneoplastic encephalomyelitis/sensory neuronopathy, usually associated with small cell cancer of the lung and anti-Hu antibodies. Amyotrophic lateral sclerosis and subacute necrotizing myelopathy of paraneoplastic origin are very rare, although casual association of these conditions with cancer cannot be ruled out. Subacute motor neuronopathy is linked to lymphoproliferative syndromes and breast cancer has been reported associated with cases of primary lateral sclerosis and the stiff man syndrome. CONCLUSIONS: Various conditions of paraneoplastic origin may affect the spinal cord. Neurological symptoms may precede the diagnosis of neoplasia, are serious and do not usually respond to either immunosuppressive treatment or treatment of the underlying neoplasm, although there are exceptions. The presence of specific antibodies in some cases facilitates early diagnosis and shows the importance of immune mechanisms in these diseases. The paraneoplastic motor neuron syndromes may present atypically: at early or late age, be of slow evolution and associated with raised protein levels of the cerebrospinal fluid or with paraproteinemia.

Antibodies, Neoplasm↗
PubMed2004

Differences in age at onset and familial aggregation between clinical types of idiopathic Parkinson's disease.

Idiopathic Parkinson's disease (PD) can be subdivided by its patterns of motor symptoms into tremor-dominant (TDT), akinetic-rigid (ART), and mixed type (MT). Our objective was to determine whether age at onset and family history are different in these three types. In total, 366 patients with PD were assigned in a standardized approach to one of the three subtypes. Age at onset and family history were obtained in all patients and all presumably affected family members were examined. Mean ages at disease onset were similar in all three groups, but distribution of age at onset was markedly different: monophasic in TDT with a peak around 60 years, biphasic in ART with two peaks, one in the middle of the sixth decade (earlier onset, ART-EO), another during the first half of the seventh decade (later onset, ART-LO), and increasing with age only in MT patients A positive family history was significantly associated only with TDT (odds ratio = 5.7) and ART-EO (odds ratio = 7.8), but not with MT or ART-LO patients. Segregation analysis suggested an autosomal recessive mode of transmission in ART-EO and an autosomal dominant mode of transmission in TDT.

Age of Onset↗
PubMed1982

On the possible role of excitatory amino acids in the striatum in mediating morphine-induced muscular rigidity.

The possible role of excitatory amino acids in the striatum in mediating tonic activity in the electromyogram (EMG) was studied. Glutamate diethylester (GDEE) (100-400 nmoles) induced a tonic activity in the EMG in a dose-dependent way when injected into the striatum. This effect was well antagonized by intrastriatal injection of quisqualic acid (5 and 25 nmoles), less by kainic acid (5 nmoles) and not significantly by N-methyl-D-aspartate (NMDA) (30 nmoles). Systemic administration of naloxone (2 mg/kg IP) did not inhibit the GDEE-induced activity in the EMG. The tonic activity in the EMG, induced by systemic administration of morphine (15 mg/kg IP) was not significantly influenced by injection of GDEE (200 nmoles) into the striatum, but was first decreased and then slightly enhanced by intrastriatal injection of quisqualic acid (25 and 50 nmoles), not affected by kainic acid (5 nmoles) and first slightly decreased and then strongly enhanced by NMDA (15 and 30 nmoles). Injection of kainic acid (5 nmoles), quisqualic acid (5 or 25 nmoles) or NMDA (30 nmoles) alone into the striatum did not produce any tonic activity in the EMG. Our results support the assumption that quisqualic acid, kainic acid and NMDA react with different types of receptors for excitatory amino acids in the striatum. Both quisqualicacid and NMDA showed a biphasic action, whereas kainic acid was ineffective. Furthermore, the activity in the EMG induced by morphine might be at least partly due to a functional antagonism of morphine against glutamate in striatal neurons.

Amino Acids↗
PubMed1999

Parkinson's disease and lower limb somatosensory evoked potentials: apomorphine-induced relief of the akinetic-rigid syndrome and vertex P37-N50 potentials.

We evaluated brainstem P30, vertex-central P37-N50 and contralateral frontal N37 somatosensory evoked potentials (SEPs) from the tibial nerve in 14 patients affected by Parkinson's disease (PD) with akinetic-rigid syndrome. In seven patients SEPs were recorded after administration of apomorphine. The cortical P37-N50 complex was either absent (five patients, eight tested sides) or significantly smaller in patients as compared to the control group (n = 18). There was a relationship between abnormalities of early vertex potentials and degree of motor impairment. Administration of apomorphine was followed by an increase in amplitude of P37-N50 response, which was maximal after 15-30 min and then progressively returned to basal values in parallel with clinical improvement. Amplitude of brainstem P30 and frontal N37 responses was within normal values and did not vary following drug administration. These results suggest that the P37-N50 complex arises from independent cortical generators, probably located in the pre-rolandic cortex, which may be selectively affected by basal ganglia dysfunction. Amplitude decrease of the P37-50 complex may reflect an abnormal processing of somatosensory inputs within the pre-central cortex due to defective modulation exerted by basal ganglia circuitry on cortical excitability. SEP potentiation following apomorphine, besides indicating that this dysfunction is partly reversible, might suggest objective method to measure therapeutic efficacy.

Aged↗
PubMed1990

An autopsy case of peroneal muscular atrophy with rigidity and tremor. Ultrastructural and systematic morphometrical studies on peripheral nerves.

An autopsy case of hereditary peroneal muscular atrophy (PMA) with rigidity and static tremor is presented. The patient developed slowly progressive distal muscular atrophy of the legs at the age of 15 years. By the age of 52 years, PMA became marked associated with pes cavus, and tremor and rigidity of the extremities were noted. Motor and sensory conduction velocities gradually depressed and lost near the end of his life. At autopsy, the major neuropathological abnormalities involved the peripheral nervous systems, and were characterized by axonal atrophy and loss of myelinated fibers. These changes involved both the proximal and distal nerves, being more severely affected in the distal. The pathological changes in other regions of the nervous systems were mainly confined to the spinal cord, dorsal ganglia and spinal nerve roots, and pigmented neurons in the brain stem. Morphometrically, the total fascicular area was much smaller than in control, but the total number of myelinated fibers greatly outnumbered that of control 75,200 to 48,200 at the proximal sciatic nerve and then gradually decreased towards the periphery; however, even in the distal sural nerve, the total number of myelinated fibers exceeded that of control (6820 to 5469). Thus, the density of myelinated fibers were much higher, being 1.5 to 2 times greater, than in control. Its abrupt decline at the distal nerve might account for neurogenic atrophy of the distal musculature. Unmyelinated fibers were slightly increased in density and not atrophic. This case is unique in its clinicopathology and does not belong to any subtypes of PMA including "neuronal plus".

Adult↗
PubMed2001

Hyperekplexia in neonates.

Hyperekplexia (startle disease) is a rare non-epileptic disorder characterised by an exaggerated persistent startle reaction to unexpected auditory, somatosensory and visual stimuli, generalised muscular rigidity, and nocturnal myoclonus. The genetic basis is a mutation usually of the arginine residue 271 leading to neuronal hyperexcitability by impairing glycinergic inhibition. Hyperekplexia is usually familial, most often autosomal dominant with complete penetrance and variable expression. It can present in fetal life as abnormal intrauterine movements, or later at any time from the neonatal period to adulthood. Early manifestations include abnormal responses to unexpected auditory, visual, and somatosensory stimuli such as sustained tonic spasm, exaggerated startle response, and fetal posture with clenched fists and anxious stare. The tonic spasms may mimic generalised tonic seizures, leading to apnoea and death. Consistent generalised flexor spasm in response to tapping of the nasal bridge (without habituation) is the clinical hallmark of hyperekplexia. Electroencephalography may show fast spikes initially during the tonic spasms, followed by slowing of background activity with eventual flattening corresponding to the phase of apnoea bradycardia and cyanosis. Electromyography shows a characteristic almost permanent muscular activity with periods of electrical quietness. Nerve conduction velocity is normal. No specific computed tomography findings have been reported yet. Clonazepam, a gamma aminobutyric acid (GABA) receptor agonist, is the treatment of choice for hypertonia and apnoeic episodes. It, however, may not influence the degree of stiffness significantly. A simple manoeuvre like forced flexion of the head and legs towards the trunk is known to be life saving when prolonged stiffness impedes respiration.

Diagnosis, Differential↗