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D Dall'Agata

Publications and source records attributed to D Dall'Agata.

17 recordsLinked to original sources
PubMed1991

Motor and sensory evoked potentials in progressive supranuclear palsy.

Motor potentials evoked in the biceps, thenar, and tibialis anterior muscles by electrical stimulation of the scalp and of the spinal regions were recorded in 12 patients with progressive supranuclear palsy (PSP) and in a control group. Abnormalities of central motor conduction for at least one muscle were present in five patients (41.7%), characterized by a long illness duration. The central sensory conduction time of the median nerve was normal, but five patients showed a depressed frontal N30 wave. These findings support the possible occurrence of functional damage to the corticospinal tracts and to the supplementary motor area in PSP.

Aged↗
PubMed1991

Motor evoked potentials (MEPs) in lacunar syndromes.

Motor evoked potentials (MEPs) evoked in the biceps, thenar and tibialis anterior muscles by electrical stimulation of the scalp and of the spinal regions were recorded in 32 patients with focal deficits due to minor cerebral ischemia of the lacunar type and in a control group. Somatosensory evoked potentials (SEPs) to median nerve stimulation were also recorded. The central motor conduction times (CMCTs) and the threshold intensities for eliciting MEPs in the relaxed muscles were significantly increased on the affected side. Central motor conduction, for at least one muscle, was altered in 18 patients. MEP abnormalities were related to pyramidal signs (though they could be observed also in a patient without any motor impairment) and occurred independently of a specific clinical picture or a radiologically confirmed lacunar lesion. SEPs were less frequently altered than MEPs.

Aged↗
PubMed1990

Impaired habituation of long-latency stretch reflexes of the wrist muscles in Huntington's disease.

Electromyographic responses to sudden wrist extension were recorded from the forearm and finger flexor muscles in 10 patients with Huntington's disease (HD) and in 10 normal controls. Stretch reflexes were characterized by a short-latency (SL) and a long-latency (LL) component both in patients and controls. Latency, duration, and size of the SL component were not different in the two groups, whereas the LL component was delayed in latency and reduced in size in HD patients. Increasing the stretch repetition rate from 0.1 to 0.4 cycles/s did not affect the SL component of either group, whereas the LL stretch reflex was reduced in size and duration in normal controls, but not in HD patients. These findings suggest an impairment of the "gain" mechanisms of the sole LL component, responsible for a desaturation of this component. This study supports the hypothesis that LL stretch reflexes are mediated by a transcortical long loop, possibly damaged in HD.

Adult↗
PubMed1990

Selective effects of repetition rate on frontal and parietal somatosensory evoked potentials (SEPs).

The effects of changing the stimulus presentation rate on early parietal (N20-P25) and frontal (P22-N30) somatosensory potentials (SEPs), evoked by median nerve stimulation, were investigated in 15 normal subjects. Stimuli were presented at 0.1, 0.4, 1.0, 4.0 and 10/sec. Only minor latency changes, mainly for the frontal P22 component, were observed when the stimulus rate was increased up to 10/sec: while the frontal P22-N30 complex was more rapidly and severely reduced in amplitude than the parietal N20-P25 complex. The differential effects of stimulus presentation rate on early frontal and parietal SEPs support the hypothesis of separate neural generators and suggest that the choice of the stimulation frequency may be critical for the interpretation of diagnostic SEP studies.

Adult↗
PubMed1990

Generalized dystonia with bilateral striatal computed-tomographic lucencies in a patient with human immunodeficiency virus infection.

We report the case of a 36-year-old, drug-addicted woman with laboratory evidence of human immunodeficiency virus infection in the central nervous system. The patient presented with generalized dystonia involving both axial and segmental muscles, mainly in the legs, and with minimal additional neurological abnormalities. A computed-tomographic scan revealed bilateral and symmetrical lucencies in the putaminal region. The possibility of an acquired immunodeficiency syndrome-related manifestation is discussed.

AIDS Dementia Complex↗
PubMed1988

Somatosensory evoked potentials in lacunar syndromes.

Parietal and prerolandic somatosensory evoked potentials (SEPs) to median nerve stimulation were recorded from 40 patients with lacunar syndromes due to CT-verified lacunar infarcts. The control group consisted of 30 age-matched normal controls. Nineteen patients showed SEP abnormalities, mainly an increase of height-covariated latency of cortical components and/or of the central conduction time. Such changes occurred independently of the clinical features of lacunar syndromes, being related more to the lesion location than to its size. SEP studies may be a useful adjunct to the clinical diagnosis of lacunar infarct, possibly also when the CT scans are normal.

Adult↗
PubMed1988

Electrical stimulation of the motor tracts in cervical spondylosis.

Motor action potentials evoked by percutaneous electrical stimulation of the scalp and of the cervical (or lumbar) vertebral region were recorded from the biceps, thenar and tibialis anterior muscles in 30 patients with cervical spondylosis. Twelve normal controls were matched for age and height. Abnormalities of central motor conduction (absence or increased central delay of cortical responses) for at least one muscle were observed in all (but one) the patients with myelopathy alone or combined with radiculopathy. An increase in latency of the responses evoked by cervical stimulation occurred in 40% of patients with radiculopathy or myelo-radiculopathy. Changes of motor conduction occurred even in the absence of abnormalities of somatosensory evoked potentials, while the opposite was never observed. Direct stimulation of the motor tracts may be of value in the functional assessment of the motor pathways in cervical spondylosis.

Adult↗
PubMed1987

Electrophysiological analysis of motor control in patients with vascular hemichorea.

An EMG analysis of motor control was performed in 4 patients with unilateral choreic movements of sudden onset, 3 of whom presented CT scan evidence of lacunar infarcts involving the contralateral striatum. The choreic dyskinesias were correlated with EMG bursts of variable duration occurring with a random order of activation. Ballistic elbow flexion movements were performed with a normal triphasic EMG pattern, but both size and duration of the first agonist burst were increased on the affected side. Abnormalities of cerebral somatosensory evoked responses were observed in 3 patients on stimulation of the side with choreic movements.

Aged↗
PubMed1987

Parietal and prerolandic somatosensory evoked responses in carotid artery reversible ischemic attacks (RIA).

Somatosensory potentials evoked by median nerve stimulation were recorded bilaterally from the prerolandic and parietal scalp in 36 patients with reversible ischemic attacks in one carotid artery distribution. Responses recorded from the affected and unaffected hemisphere were compared. SEP abnormalities were observed over the affected hemisphere in 22 subjects (61.1%), irrespective of number and/or duration of episodes, and appeared selectively correlated to their clinical features. SEP studies proved to be more sensitive than conventional EEG recordings and are suitable for evaluation of the functional impairment of specific cerebral areas following transient cerebral ischemia. The occurrence of SEP abnormalities in RIA may represent an unfavourable sign, being more frequent in patients with evidence of internal carotid artery disease.

Adult↗
PubMed1986

Thalamic dementia: report of a case with unusual lesion location.

Thalamic dementia usually results from a bilateral paramedian thalamic infarction. We report a case with typical clinical and neuropsychological features of thalamic dementia, but with CT evidence of an unusual and asymmetrical location of ischemic lesions. Somatosensory evoked potential recordings were consistent with a left medial thalamic infarction, associated with a contralateral lesion, possibly at lemniscal level. This case suggests that thalamic dementia may develop following a unilateral paramedian thalamic infarction.

Adult↗
PubMed1986

Long-term prognosis of patients with lacunar syndromes.

A follow-up study of 107 patients with lacunar syndromes has been performed using the analysis of the survival curves and the recurrence curves for new focal cerebrovascular acute episodes. At the end of the 7th year of follow-up, the survival rate of lacunar patients was 479 per 1000, lower than the survival rate of the normal population matched for sex and age (755 per 1000). A more severe prognosis was observed in subjects over 65 years of age, in patients with pseudobulbar syndrome, hypertension and higher degree of disability. The average recurrence rate for new cerebrovascular episodes was 4.74 per 100 patient-years, much lower than that in survivors from cerebral infarction.

Age Factors↗
PubMed1985

Headache in transient ischemic attacks (TIA).

The evaluation of headache in patients with transient ischemic attacks (TIA) has various sources of difficulty, the definition of TIA being the most relevant. The classical definition needs to be supplemented with a normal CT scan if a misleading diagnostic statement is to be avoided. The clinical features of 90 patients suffering from TIA and who had contrast-enhanced CT scans are reported. Headache occurred in 30% of the patients. Headache prevailed in patients with vertebrobasilar TIA compared with carotid TIA (p less than 0.05). Headache prevailed as a preceding (24 h) and/or concomitant sign compared with other neurological symptoms (77.8% of the patients). Headache was ipsilateral, in the anterior half of the head in the carotid TIA and in the posterior half of the head in the vertebrobasilar TIA. In about 50% of the patients generalized non-localized headache occurred. Headache usually preceded the neurological symptoms in cases of arterial occlusion (20 carotid, 3 vertebral artery), usually appearing during or after the attack in cases without arterial occlusion. Only 2 cases out of 20 with positive CT scan had headache. These two patients suffered from a rather large hypodense lesion. The other 18 patients showed lacunar lesions. Different hypotheses concerning the physiopathology of the headache associated with TIA are discussed.

Adult↗
PubMedDate not supplied

Abnormalities of parietal and prerolandic somatosensory evoked potentials in Huntington's disease.

Cervical, parietal and prerolandic somatosensory evoked potentials (SEPs) to median nerve stimulation at the wrist were recorded with an earlobe reference in 24 patients with Huntington's disease (HD) and in 24 age-matched normal controls. Cortical responses of abnormal wave form and reduced amplitude were constantly observed in HD patients. SEP changes affected more severely the prerolandic (P22/N30) pattern, which could not be recognized in two-thirds of patients, than the parietal (N20/P27) pattern, which could be identified in all cases. The N20 latency and the central conduction time (N13-N20 interval) were significantly increased. The occurrence of abnormalities of central conduction and of a predominant involvement of the prerolandic SEP pattern suggests an impairment of impulse transmission along the somatosensory lemniscal pathway at subcortical, possibly thalamic, level in HD.

Adult↗