PURPOSE: To determine the a-wave latency of the electroretinograms (ERGs) recorded from control subjects and patients with retinal diseases. METHODS: The a-wave latency and implicit time (IT) were measured retrospectively from the ERGs of 40 control subjects and 99 patients. The patients included 9 with complete congenital stationary night blindness ...

To evaluate the effect of early treatment of congenital hypothyroidism on central nervous system development, auditory brainstem evoked potentials were determined in 32 patients with hyperthyrotropinemia diagnosed during neonatal screening. The patients included 27 with congenital hypothyroidism and 5 with transient hypothyroidism. Abnormal auditory brainstem evoked potential tracings were found ...

AIM: To determine the value of the blink reflex as a predictor of outcome of idiopathic peripheral partial facial paresis. METHOD: The study included 30 patients suffering from acute idiopathic peripheral facioparesis and 30 age- and sex-matched healthy controls. Patients with symptomatic disease were excluded on the basis of neuroradiologic ...

In patients with degenerative ataxia, various abnormalities in motor cortex activation by transcranial magnetic stimulation (TMS) have been observed, including a reduction of intracortical facilitation and a lengthening of the silent period. However, the groups of patients examined in previous studies were heterogeneous, involving patients with autosomal-dominant and idiopathic cerebellar ...

The visual evoked potential (VEP) record in response to a pattern stimulus is a non invasive and reliable method of detecting central and peripheral nerve system abnormalities. VEP recording have been used in animals with fulminant hepatic failure, and also in-patients with hepatic encephalopathy and acute severe hepatitis. Our aims ...

We studied the Erb's point potential with supramaximal stimulation of the median nerve in 14 consecutive patients with clinical and electrophysiological evidence of unilateral brachial plexopathy and in normal controls. Both arms were studied in each individual. In each patient, the ratio of amplitude of recorded Erb's point potential from ...

OBJECTIVES: We aimed to test the hypothesis that subclinical cognitive brain dysfunction in cirrhotic patients would deteriorate after a transjugular intrahepatic portosystemic shunt (TIPS) in the absence of clinically detectable hepatic encephalopathy. METHODS: Out of 49 consecutive cirrhotic patients receiving elective TIPS for recurrent variceal hemorrhage, we identified 22 patients ...

Short-latency somatosensory evoked potentials (SSEPs) were measured before and after intermittent cervical traction therapy to serve as objective indicators of therapy effectiveness. The subjects were 29 patients with myelopathy, 23 with cervical radiculopathy, 28 with cervical sprain, and 26 healthy individuals. SSEPs were recorded by stimulating the median nerve, and ...

BACKGROUND: The spinocerebellar ataxias (SCAs) are clinically heterogeneous disorders caused by triplet repeat expansions in the sequence of specific disease genes. Spinocerebellar ataxia type 8 (SCA8), originally described in a family characterized by pure cerebellar ataxia with slow disease progression, presents with expansion of combined CTA/CTG repeats. OBJECTIVE: To perform ...

While evoked potentials are sensitive tools for diagnosing multiple sclerosis, little is known about their prognostic value and their role in determining the course of the disease. To validate the visual and motor evoked potentials (VEP and MEP) as measures for the course of multiple sclerosis, we examined prospectively 30 ...

Correlations were drawn between subscores of a cerebellar motor dysfunction (CMD) scale and simple reaction time (RT) and movement time (MT) in patients diagnosed with olivopontocerebellar atrophy (OPCA). Poor performance on CMD subscores was correlated with long disease duration and lengthening of visual and auditory RT and MT, with the ...

An advanced method for analyzing the patterning of successive galvanic skin responses (GSR) is presented. The proposed method is based on principal component analysis in which the vector containing the measured signal is presented as a weighted sum of orthogonal basis vectors. The method is tested using measurements from 20 ...

OBJECTIVE: The aim of the study was to investigate the abnormalities of brainstem auditory evoked potentials (BAEP) in patients with severe chronic obstructive pulmonary disease (COPD). METHODOLOGY: Twenty-one patients with severe COPD (16 men, five women; mean age: 64 +/- 6.5 years), in whom other causes of BAEP abnormalities had ...

Chronic hypoxemia is known to cause peripheral neuropathy (PNP) in chronic obstructive pulmonary disease (COPD) patients. We aimed to know how often PNP is encountered in such patients and the changes in the central nervous system (CNS) if any. We enrolled 32 patients (30 M, 2 F; mean age +/- ...

BACKGROUND: As a parameter for the evaluation of the vestibular evoked myogenic potential (VEMP), amplitude has been used clinically. However, the significance of latency has not been considered. OBJECTIVE: To clarify the diagnostic value of latencies of the VEMP. DESIGN: We reviewed records of the VEMP of patients with various ...

Ataxia with vitamin E (Vit E) defciency (AVED) is an autosomal recessive disorder caused by mutations of the alpha tocopherol transfer protein gene. The Friedreich ataxia phenotype is the most frequent clinical presentation. In AVED patients, serum Vit E levels are very low in the absence of intestinal malabsorption. As ...

OBJECTIVE: The aim of the study was to determine how odor processing is altered in patients with unilateral supratentorial brain tumors. METHODS: Olfactory event-related potentials (OERPs) were evaluated in 10 patients with unilateral brain tumors of the frontal or temporal lobe in response to linalool and allylcaproate. Both odors were ...

OBJECTIVE: Patients with acromegaly have an increased risk of ventricular dysrhythmias and sudden death. Late potentials in a signal-averaged electrocardiogram (SAECG), a predictor of ventricular dysrhythmias, are frequently seen in patients after previous myocardial infarction, but little is known about the prevalence of late potentials in acromegaly. The aim of ...

OBJECTIVES: Little is known about the frequency of abnormal visually evoked potentials (VEPs) in patients with respiratory chain disorders (RCDs). We thus wanted to investigate the frequency of abnormal VEPs in RCDs, how often VEPs are abnormal despite normal visual acuity, and which of the VEP variables are most often ...

The alien hand sign (AHS) is often encountered in patients with corticobasal ganglionic degeneration (CBGD), revealing a unilateral dysfunction of the motor system of unknown pathophysiology. We examined the possibility of an abnormal cortical representation of hand muscles in 10 patients with probable CBGD and a prominent AHS. Cortical maps ...

OBJECTIVES: To assess impairment of cognitive functions occurring in patients with posttraumatic headache as a consequence of a minor cranial trauma in the absence of organic damage involving the central nervous system. BACKGROUND: The term posttraumatic syndrome defines a stereotypic set of symptoms following traumatic brain injury that are subjective ...

OBJECTIVES: To report follow-up studies of cerebellar stimulation in patients with acute cerebellar ataxia (ACA). METHODS: We studied two patients with ACA. One patient also had decreased deep sensations in the feet due to combined diseases such as diabetic polyneuropathy and lumbosacral radiculopathies. We applied the technique of electrical stimulation ...

We investigated the relationship between the latency of the Nb wave of the auditory evoked response (AER) and periods of awareness during propofol anaesthesia. In the anaesthetic room before cardiac surgery the AER was recorded continuously in 14 patients. Awareness was measured by the ability of the patient to respond ...

The authors studied the origin of the scalp P13-like potential in median somatosensory evoked potentials, which have been reported to be preserved in patients with cervicomedullary lesions or in brain death. There were five patients with high to middle cervical lesions (C2/3 or C3/4 level). Small P13-like potentials after P11 ...

The present study has been undertaken to describe brainstem auditory evoked potential (BAEP) changes in tubercular meningitis (TBM) and correlate these with CT scan and MRI findings. 24 patients with TBM were subjected to clinical evaluation and CT scan or MRI study. Outcome was defined by 3 month Barthel index ...

We describe a peculiar form of late onset paroxysmal cerebellar ataxia including clinical features similar to episodic ataxia type 2 (EA2) but unresponsive to acetazolamide. Four unrelated patients were clinically investigated. Neuropathological examination was performed in one patient and molecular analysis in all four. All 47 exons of CACNA1A were ...

OBJECTIVE: Behcet's disease is the association of recurrent aphthous stomatitis with genital ulceration and eye disease. Neurologic involvement patterns include meningomyelitis, a brain stem syndrome, pyramidal and extrapyramidal abnormality and stroke. In the present study, subclinical involvement was investigated by using P300 in Behcet's patients without neurological manifestation. METHODS: Fifteen ...

A total of 13 patients, who were diagnosed with localized brainstem lesions using MRI, were investigated. The diagnoses were multiple sclerosis in five patients, brainstem hemorrhage in three patients, pontomedullary infarction in one patient and Wallenberg's syndrome in four patients. In addition, 42 ears of 21 normal adult volunteers were ...

The functional status of vestibulo-collic reflexes in the sternocleidomastoid (SCM) muscles was investigated in 24 patients with spasmodic torticollis using small, abrupt 'drops' of the head. None had been treated with botulinum toxin injections during at least 4 months preceding the study. Eight of the patients, four of whom had ...

PURPOSE: To verify the efficiency and objectivity of the pattern visual evoked potential (VEP) for organic disorders of the cortical visual system. METHODS: This retrospective study evaluated VEP in 19 patients diagnosed with psychogenic visual disturbance, 7 patients with malingering, and 37 age-matched normal volunteers. Transient (3 reversals per second) ...

The aims of this study were to examine the late components of the auditory event-related potentials (AERPs), i.e. N(100), P(200) and P(300), in recently detoxified alcohol-dependent patients compared to normal controls and to investigate whether there is a relationship between alterations in these AERPs and signs of activation of the ...

Needle EMG may be negative in mild or predominantly sensory lumbosacral radiculopathies. In such cases, an increase in the latency of the soleus H-reflex is a useful diagnostic criterion for establishing sensory fiber compromise at the S1 root level. However, if clinical signs of radicular involvement are lacking, the latency ...

We report results of vestibular-evoked myogenic potentials (VEMPs) in patients with cerebellopontine angle tumors and compare results obtained using clicks with those obtained using 500 Hz short tone bursts (STB). We reviewed the records of 87 patients with cerebellopontine angle tumors. Clicks (0.1 ms, 95 dB nHL) were presented to ...

We analysed somatosensory evoked potentials (SEPs) in the patients with juvenile myoclonic epilepsy (JME) in order to find out if sodium valproate (VPA) affects SEP latencies and amplitudes. SEPs were studied in 23 patients with JME receiving VPA monotherapy, eight patients with JME not receiving VPA, and a control group ...

OBJECTIVE: to test the effects of tendon stimulation on isometric voluntary contraction. METHODS: Twenty patients with dystonia (12 patients with generalized and eight with task-specific dystonia) and 10 normal healthy subjects participated in the study. The tendon of the extensor carpi radialis muscle was stimulated with electrical stimuli at the ...

A systematic evaluation of anterior horn cell, motor and sensory pathways is possible by electromyography (EMG), motor (MEPs) and somatosensory (SEPs) evoked potentials, respectively, which may provide valuable information on acute transverse myelitis (ATM). In a prospective hospital-based study, EMG, MEP and SEP studies were carried out on admission and ...

With the intention to assess remote effects of cerebellar dysfunction, 23 patients with inherited or idiopathic cerebellar ataxia were studied with positron emission tomography (PET) and 2[18F]fluoro-2-deoxy-D-glucose (FDG). Eight patients (group 1) suffered from early onset cerebellar ataxia (EOCA, age of symptom onset <20 years), nine patients (group 2) from ...

OBJECTIVE: To assess the viability of sympathetic sudomotor fibers in carpal tunnel syndrome (CTS). METHODS: We recorded sympathetic skin response (SSR) with a multichannel recording system. Forty-four patients with CTS (51 hands), 7 patients (7 hands) with asymptomatic median mononeuropathy at the wrist (MMW), and 20 normal subjects (20 hands) ...

The purpose of this study was to examine the relationship of abnormal short-latency somatosensory evoked potentials (SSEPs) recorded by a noncephalic reference montage with clinical variables in cervical myelopathy patients and to reexamine the diagnostic utility of SSEPs in such patients. We studied cervical SSEPs elicited by stimulating the median ...

OBJECTIVES: Patients with primary palmar hyperhidrosis (PPH) might exhibit hyperexcitability of the reflex circuits involved in sweating. We hypothesized that this hyperexcitability could become evident in the study of the excitability recovery curve of the sympathetic sudomotor skin response (SSR). METHODS: In 10 patients with PPH and 10 healthy volunteers ...

To estimate vestibulo-collic reflexes in patients with spinocerebellar degeneration (SCD), vestibular evoked myogenic potentials (VEMPs) were recorded in 16 patients with SCD and in 9 normal subjects. The patients with SCD were classified into three groups: those with olivo-ponto-cerebellar ataxia (OPCA; n = 10); those with cortical cerebellar atrophy (CCA; ...

F-waves in the extremities result from the backfiring of antidromically activated anterior horn cells and F-waves of the mentalis muscle can be also elicited after stimulation of the marginal mandibular branch of the facial nerve. In order to investigate the influence of the descending pathway of the excitability of the ...

Spinocerebellar ataxia 8 (SCA8) is caused by a CTG repeat expansion in an untranslated region of a recently cloned gene on 13q21. The pathogenic role of this trinucleotide repeat was evaluated by examining 154 Finnish ataxia patients and 448 controls. Expansions ranging from 100 to 675 repeats were present in ...

Median nerve somatosensory evoked potentials (SEP) were recorded in 30 patients with multiple sclerosis. The examined patients had an expanded disability status scale (EDSS) between 0 and 6. The primary cortical potential N20, the subcortical potentials P14, N13b, N13a and the peripheral potential P9 were recorded simultaneously. In 5 patients ...

In the present study we investigated whether the precentral component (N30) of short somatosensory evoked potentials (SEPs) to median nerve stimulation may be modified by peripheral neuromuscular blocking agent in patients affected by rigidity. We, therefore, recorded SEPs in nine Parkinson's disease (PD) patients and in seven psychotic patients affected ...

A series of electrophysiological investigations were performed over a 6-month period in two patients affected by fulminant Guillain-Barré polyradiculoneuropathy, who developed an ascending paralysis leading, within 72 h, to flaccid quadriplegia, internal and external ophthalmoplegia, absence of all brainstem reflexes and no respiratory effort: the clinical state resembled brain death. ...

OBJECTIVE: We report an electrophysiological method to differentiate amyotrophic lateral sclerosis (ALS) from cervical spondylotic myelopathy (CSM). METHODS: Motor evoked potentials (MEPs) by transcranial magnetic stimulation were investigated in patients with ALS (n=10) and CSM (n=9). In addition to limb MEPs using the triple stimulation technique (TST) at upper limbs, ...

To determine the diagnostic efficacy of late responses and of magnetic stimulation in the electrodiagnostic evaluation of lumbosacral radiculopathies, 42 patients with acute monoradiculopathies of L5 or S1 were examined. We performed conventional nerve conduction studies, F-wave studies, needle electrode examination (NEE) and magnetic stimulation. The results were compared with ...

OBJECTIVE: Evaluation of changes in the peak latencies of sensory evoked potentials in different patient groups, to evaluate differences in metabolic encephalopathy of critically ill patients with multiple organ failure as a result of septic or nonseptic conditions. DESIGN: Prospective cohort study. SETTING: Intensive care units of the university hospital, ...

This study developed a standardized procedure for provoking cataplexy, which facilitated observation of the physiologic changes occurring with cataplexy. Data were obtained from narcoleptic patients recruited from a sleep disorder center. Patients were asked to describe the nature and frequency of cataplexy, as well as their typical emotional triggers. Referring ...