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D De Grandis

Publications and source records attributed to D De Grandis.

At least 37 records · Page 2Linked to original sources
PubMed1997

Guidelines for the therapeutic use of botulinum toxin in movement disorders. Italian Study Group for Movement Disorders, Italian Society of Neurology.

Since its introduction in the early '80s the use of botulinum toxin has improved the quality of life of the patients affected by movement disorders. Toxin's neuromuscular blocking action allows a symptomatic treatment of those clinical conditions characterised by excessive muscular activity. Although the dosages used are safe and the side-effects are reversible, a correct use of botulinum toxin depends on the knowledge of its clinical pharmacology and of the anatomy of the body segments to be injected. In addition, the treatment of more complex conditions, i.e. laringeal dystonia, imposes an inter-disciplinary approach and specialised injection techniques. In this review, the Italian Study Group on Movement Disorders presents the consensus guidelines for the therapeutic use of botulinum toxin in movement disorders. The main toxin types, their use and administration modalities, and the training guidelines will be presented.

Botulinum Toxins↗
PubMed1997

Motor evoked responses to paired cortical magnetic stimulation in Parkinson's disease.

We evaluated cortical excitability in patients with Parkinson's disease (PD) using paired magnetic stimulation. This recent technique allows to study the cortical inhibition after motor evoked potential (MEP) and its modulation at different intensities of stimulation and interstimulus intervals (ISIs). At low stimulus intensity and at ISIs of 40-75 ms we observed, in PD patients, a greater test MEP inhibition, which might be due to a lower facilitatory effect of conditioning MEP on the motor cortex. At high stimulus intensity, in PD patients, a consistent inhibition of test MEP persisted and, at ISIs of 75-150 ms, it did not reach the amplitude of conditioning MEP as in normal subjects. Some clinical and neurophysiological features, like a silent period of shorter duration, demonstrated in PD patients a decrease of the inhibitory input to the motor cortex. On the contrary, the persistence of test-MEP inhibition at high stimulus intensity could also suggest a prevalence of inhibitory activity when an effective and phasic activation of the corticospinal system is required.

Aged↗
PubMed1997

Lower-limb lengthening in short stature. An electrophysiological and clinical assessment of peripheral nerve function.

We assessed peripheral nerve function during and after lower-limb lengthening by callotasis in 14 patients with short stature, using motor conduction studies. Four patients with short stature of varying aetiology showed unilateral and one showed bilateral weakness of foot dorsiflexion. Both clinical and electrophysiological abnormalities consistent with involvement of the peroneal nerve were observed early after starting tibial callotasis. There was some progressive electrophysiological improvement despite continued bone distraction, but two patients with Turner's syndrome had incomplete recovery. A greater percentage increase in tibial length did not correspond to a higher rate of peroneal nerve palsy. The function of the posterior leg muscles and the conduction velocity of the posterior tibial nerve were normal throughout the monitoring period. The F-wave response showed a longer latency at the end of the bone distraction than in basal conditions; this is probably related to the slowing of conduction throughout the entire length of the nerve.

Achondroplasia↗
PubMed1997

The therapeutic use of botulinum toxin.

Since Alan Scott's research, botulinum toxin (BoNT) has been used in several diseases or conditions characterised by muscular overactivity. BoNT acts on either neuromuscular or autonomic cholinergic junctions. Seven different serotypes are known, with antigenic specificity and different therapeutic profiles. BoNT is made up of a heavy chain, involved in binding and membrane translocation, and a light chain, involved in blocking neuroexcytosis. Each serotype shares a specific acceptor on the presynaptic membrane of a cholinergic junction. The available BoNT preparations differ in toxicity, purity and stability. Injection of the neurotoxin produces several modifications at a neuromuscular junction. Axonal sprouting, muscular fibre atrophy, and new end-plates are the most evident histological events after BoNT treatment. They appear to be reversible in untreated muscles. Diffusion can occur at first by haematogeneous or local BoNT spread. Several factors, such as dose, volume, site of injection, muscle size, and muscular fascia, can influence the amount of diffusion and possible side-effects. After prolonged BoNT treatment patients can become unresponsive. Antibodies directed against BoNT have been observed with ELISA or mouse bioassay. Different serotypes have been used to treat non-responder patients. Novel toxins with lower immunogenicity and prolonged clinical efficacy are required for more effective treatment.

Journal Article↗
PubMed1996

Surface mechanomyogram reflects muscle fibres twitches summation.

The aim of this work is to define the pattern of summation of the muscle fibre twitches in the surface mechanomyogram (MMG) generation process. For this purpose, two groups of muscle fibres of the extensor digitorum communis (EDC) were stimulated using needle electrodes. To these two artificial (because made by different muscle fibre types) motor units (MU1 and MU2), we administered: (a) separate stimulations: 3 and 9 Hz (MU1), 8 and 20 Hz (MU2) for 5 s; (b) simultaneous stimulation: 3 Hz (MU1) + 8 Hz (MU2); 9 Hz (MU1) + 20 Hz (MU2) for 5 s. The mechanomyograms, recorded during separate stimulation of MU1 and MU2, were linearly summated for the generation of a mechanomyographic signal to be compared with the one detected during (b) stimulation procedure. The bispectrum and the bicoherence of the generated MMG (MMGg) and of the MMG recorded during simultaneous (MMGs) stimulation were calculated for the detection of the quadratic non-linearity in the system responses. It was found that the MMGg and MMGs presented difference in the bispectrum and bicoherence index only when the 9-20 Hz stimulation pair was considered In conclusion, our data indicate that the MMG derives from the summation of the active muscle fibres twitches and that the latter is linear only for very low firing rates. This is to be carefully considered when studies on MMG modelling will be undertaken.

Electric Stimulation↗
PubMed1996

Botulinum toxin treatment in the facial muscles of humans: evidence of an action in untreated near muscles by peripheral local diffusion.

In a population of subjects with blepharospasm and facial hemispasm treated for the first time with botulinum toxin type A (BT) in the orbicularis oculi muscle, we performed an electrophysiologic study (compound muscle action potential and motor evoked potential) to assess whether BT effect could be detected in near untreated muscles (orbicularis oris and masseter). There was a significant BT action in nearly untreated muscles with different peripheral innervation that can be explained by local diffusion of the drug.

Action Potentials↗
PubMed1996

Cryoglobulinemic neuropathy related to hepatitis C virus infection. Clinical, laboratory and neurophysiological study.

Peripheral neuropathy is frequently reported in mixed cryoglobulinemia. As a close relationship has been established between mixed cryoglobulinemia and hepatitis C virus (HCV), the clinical, neurophysiological, and serologic findings of five patients affected by neuropathy, cryoglobulinemia and HCV infection were investigated. HCV infection was ascertained by the presence in the serum of anti-HCV antibodies detected by enzyme-linked immunosorbent assay(ELISA), and of HCV RNA assessed by polymerase chain reaction (PCR). Initial symptoms included paresthesias and painful dysesthesias in the legs. Later on, the patients developed a mainly asymmetric axonal polyneuropathy or a multifocal neuropathy associated with signs of systemic vasculitis. In this case series we report the short-term prognosis, as well as the response to interferon (IFN) alpha and conventional treatment. The presence of HCV RNA supports the hypothesis that a persistent HCV infection might be involved in the pathogenesis of mixed cryoglobulinemia and cryoglobulinemia-associated disorders.

Adult↗
PubMed1995

Sympathetic skin response in patients with Duchenne muscular dystrophy.

To verify an eventual disfunction of the palmar sympathetic skin activity in Duchenne Muscular Dystrophy, we studied the sympathetic skin response (SSR) with endogenous, Deep Breathing (DB-SSR), exogenous Startle (SE-SSR) and Electric type stimuli (EE-SSR) in a group of patients and a control group. At the same time as the SSR, the heart rate (HR) and the basic R-R interval variation (RRIV) as well as the EMG diaphragmatic activity were checked. In this way, significant differences in the latency (p = 0.02) and amplitude (p = 0.009) values of the EE-SSR and in the amplitude values of the SE-SSR (p = 0.001) and of the DB-SSR (p = 0.02) were noted in the DMD group compared to the control group. In the group of patients the rise in latency of the EE-SSR correlates with the age (p = 0.0001) and with the reduction of its amplitude (p = 0.03). This last parameter correlates with the stage of the illness (p = 0.02). In the control group the mean amplitude of the EE-SSR is approximately 30% greater than that of startle and 50% of deep breathing. Although with amplitudes homogeneously reduced, these ratios are also conserved in the DMD group. Moreover the HR is greater (p = 0.0001) whilst the RRIV is reduced (p = 0.02) in the group of the patients. However these parameters do not correlated either to the cardiac involvement or to the stage of the illness. The presence of the SSR for all the modalities of stimulation indicates the substantial integrity of the afferent and the efferent paths of the ANS. The alterations in latency and amplitude of the SSR in the patients could be the consequence of a lack of dystrophin at the level of the sudoriparous myopithelium in analogy to what has been demonstrated in the mdx mouse.

Adolescent↗
PubMed1994

Pattern of motor evoked response to repetitive transcranial magnetic stimulation.

The changes in motor pathway excitability, induced by pairs or trains of transcranial magnetic stimuli, were studied. The motor evoked potential (MEP) pattern depended on the interstimulus interval (ISI), the stimulus intensity and the type of coil employed. At low intensity, using either an 8-shaped or a circular coil, there was a test MEP inhibition at ISIs of 50-150 msec. During trains of stimuli, this inhibition showed a periodic trend with an interval of 250-300 msec. At high stimulus intensity we observed a progressive disappearance of test MEP inhibition which was incomplete with an 8-shaped coil and complete, reaching an MEP facilitation, with a circular coil. The inhibition observed at low intensity might be due to cortical inhibitory mechanisms. The effect found at high intensity and with the circular coil could depend on the activation of deeper and at higher threshold cortico-spinal structures. This hypothesis, however, does not explain the simultaneous delay of the test MEP latency which might depend on the activation of different cortico-spinal pathways.

Adult↗
PubMed1994

Spinal somatosensory evoked potentials in patients with tethered cord syndrome.

We studied the electrophysiological changes occurring in six patients with tethered cord syndrome. Evidence of spinal malformations was provided by magnetic resonance imaging. The functional assessment of the spinal cord was performed by analysing both spinal and cortical somatosensory evoked potentials. The evoked electrospinogram was recorded from the thoracic and lumbosacral spinous processes. The N22 lumbosacral potential was selectively affected, being rostrocaudally displaced and reduced in amplitude or even absent in patients with neurological signs indicating a segmental lower cord lesion. Inter-peak somatosensory evoked potentials latency was normal in all cases, suggesting that ascending axonal potentials in the dorsal column fibres may be synchronized. Segmental potentials of the lumbosacral response, originating from the post-synaptic activity of dorsal horn interneurons, are selectively affected in this syndrome resulting from the rostrocaudal displacement of the spinal cord due to tethering. Our findings in the clinical field are consistent with previous experimental evidence indicating a different sensitivity of the gray vs. white matter to progressive stretching.

Adult↗
PubMed1994

Variability of tibial nerve early cortical potentials in normal subjects.

The aim of the study was to calculate and test the variability of several tibial nerve SEP parameters, particularly scalp amplitude distribution, with a view to obtaining more reliable clinico-electrophysiological correlations. The parameters were evaluated in 20 healthy subjects using a simple, easily reproducible recording method. The absolute latency of the P40 wave was greater than that of the N37 wave, except in two cases. Paradoxical lateralization was present in all subjects. On the basis of the scalp amplitude distribution of the ipsi- and contralateral potentials, three distinct groups were identified: a) dominance of ipsilateral P40, 29 sides; b) dominance of P37, 15 sides; and c) equivalent amplitude of P37 and ipsilateral P40, 5 sides. The individual amplitude values of these potentials were plotted on a normogram. The results suggest that (i) the absence of one or more early cortical SEPs may be considered abnormal; (ii) when SEP scalp lateralization is present, it may be useful to compare the amplitude distribution of the individual components in normal and pathological populations; and (iii) for this purpose, lateralized potentials are more reliable owing to their lower degree of amplitude dispersion.

Adult↗
PubMed1993

The influence of muscular lengthening on cramps.

Muscle cramps induced by voluntary contraction and by electrical stimulation of the peripheral nerve were studied electrophysiologically in 10 healthy subjects. The aim was to verify that cramps can be evoked by electrical stimulation of peripheral nerve and to clarify the physiological mechanism responsible by analyzing the effect of muscular stretching on cramps. Our results showed: (1) Cramps can be induced even after peripheral nerve block by electrical stimulation distal to the block. (2) No cramps were recorded during or following maximal voluntary contraction without muscular shortening, while 7 of 10 subjects showed a true cramp following maximal effort with shortening of the muscle. (3) Muscle stretching caused a sudden interruption of cramps induced by either voluntary contraction or electrical stimulation of the peripheral nerve, even after the induction of nerve block. (4) The lengthening state of the muscle can strongly influence the possibility of evoking cramps by electrical stimulation of nerve. Our study verifies the experimental model proposed by Lambert in 1969, emphasizing the relevance of frequency of stimulation and confirming the hypothesis that cramps are of peripheral origin. The effects of muscle stretch and lengthening on cramp interruption and development also have a peripheral mechanism.

Adult↗
PubMed1993

Botulinum toxin treatment in patients with focal dystonia and hemifacial spasm. A multicenter study of the Italian Movement Disorder Group.

In six Centers belonging to the Italian Movement Disorder Study Group, the efficacy of botulinum toxin treatment was evaluated in an open collaborative study in 251 patients with focal dystonia and hemifacial spasm. The percentage of functional improvement ranged from 66% to 81% in patients with blepharospasm, from 40% to 51% in patients with spasmodic torticollis and from 73% to 81% in those with hemifacial spasm. Good results were also obtained in patients with oromandibular dystonia, laryngeal dystonia and writer's cramp. Side effects were mild and transient. Local botulinum toxin injection is the first choice symptomatic treatment in focal dystonia and hemifacial spasm.

Adult↗
PubMed1992

Polyneuritis cranialis: clinical and electrophysiological findings.

A 13 year old boy, developed bilateral facial weakness, dysphonia and dysphagia acutely after a febrile illness. Neurological examination and MRI of the brain were normal. The CSF protein level increased. Blink reflex monitoring during clinical recovery was consistent with demyelination of the lower cranial nerves innervating the branchial arch musculature, a rare variant of Guillain-Barré syndrome.

Adolescent↗
PubMed1992

Idiopathic facial paralysis: new therapeutic prospects with acetyl-L-carnitine.

The study population was composed of 43 patients affected by idiopathic facial paralysis (20 males and 23 females), aged between 11 and 67. The study was carried out in a double-blind, randomized, placebo controlled manner. Acetyl-L-carnitine was given in an oral dose of 3 x 1 g daily for 1 month, along with a daily oral administration of 50 mg of methylprednisolone for 14 days. The evaluation was made by means of electromyograms (EMG) of the orbicularis oculi and oris muscles, by the Schirmes lacrimation test, by stapedial reflex test and a score scale for clinical assessment of paralysis. Results so far obtained have shown an earlier functional recovery of the nerve in those patients treated with acetyl-L-carnitine. Comparison between the affected and unaffected sides of the face revealed a statistical significance in the treated group (p < 0.05) as well as the amplitudes of the muscle action potentials (MAP) between the affected sides (p < 0.01).

Acetylcarnitine↗
PubMed1990

Far-field and cortical somatosensory evoked potentials in motor neuron disease.

We examined median somatosensory evoked potentials (SEPs) in 26 patients with sporadic motor neuron disease (MND). SEPs were recorded with multiple scalp derivations, using both the midfront and the earlobe as references for each subject. Central conduction time (CCT) was abnormal in three patients, but only when using the midfront reference. Moreover, an exclusive alteration of the early prerolandic potentials (absent or delayed P20 and/or P22) was noted using the earlobe reference in amyotrophic lateral sclerosis and in progressive bulbar palsy (54% and 50% of patients, respectively) but not in progressive muscular atrophy. These findings correlated with clinical evidence of upper motor neuron signs and with the severity of the disease. In agreement with recent views regarding the sources of the early anterior cortical responses, neuronal loss in the motor cortex may be considered as affecting the generator sites of these potentials.

Adult↗
PubMed1989

Fibrillatory activity and other membrane changes in partially denervated muscles.

Rat soleus muscles were partially or totally denervated by sectioning the radicular nerve L5 or the radicular nerves L3 through L6, respectively. Three days after these procedures, fibrillation potentials were not observed in the case of partial denervation, whereas they were clearly detectable after total denervation. At later times, spontaneous spike activity also developed in the partially denervated muscles. The difference in time of onset of fibrillation between partially and totally denervated muscles was confirmed by a more gradual increase in the number of acetylcholine receptors and a greater sensitivity to tetrodotoxin of the former muscles. These differences between partially and totally denervated muscles are interpreted on the basis of the different amounts of nerve breakdown products generated in the two situations.

Acetylcholine↗