Saccadic eye movements analysis in the early diagnosis of myasthenia gravis.

Saccadic eye movements were examined by electro-oculography in 21 patients with suspected myasthenia gravis. The presence of dissociated nystagmus and quiver eye movements was also assessed. The aim of the study was to assess the diagnostic value of saccadic abnormalities in the early stage of the disease. Pathological oculographic findings consisted of intra and post saccadic disorders and intersaccadic variability. A fatigue test was useful in detecting latent disorders in most patients. A Tensilon test was positive in 11 out of 16 patients with oculographic abnormalities. Diagnostic problems, apparently paradoxical findings and differential involvement of extraocular muscle fibers are discussed.

Multisystem involvement of the central nervous system in Strümpell's disease. A neurophysiological and neuropsychological study.

The multisystem involvement of the central nervous system (CNS) in familial spastic paraplegia (FSP) has not been fully investigated by means of complete neurophysiological and neuropsychological examinations. The classification which distinguishes pure and complicated forms of FSP, is based on clinical features and does not take into account the possibility that clinically silent lesions of the CNS can be identified by means of adequate tests. The study was intended to assess the subclinical and multisystem involvement of the CNS in a group of 11 patients affected by FSP, clinically distinguished in 7 pure forms and 4 complicated forms. Neurophysiological tests included saccadic eye movements analysis, visual and auditory brain stem evoked responses. Neuropsychological examination was devised by means of a special purpose mental deterioration battery. Our results, showing a high incidence of multisystemic subclinical involvement of the CNS, confirm and extend the concept that FSP is a multisystemic degenerative disease of the CNS, and that the existence of "pure" forms should be reconsidered.

Age-dependent changes in visually guided saccadic eye movements.

Voluntary horizontal saccadic eye movements (SEM) were recorded in 148 drug free healthy subjects (15-75 years of age). None had history and/or objective evidences of CNS abnormalities. SEM recordings took place always at the same time of the day, after a standard lunch. Peak saccadic velocity (PSV), saccade latency (SL) and saccade accuracy (SA) were extracted for each saccade session. A negative linear correlation was found between SEM parameters (PSV, SA, SL) and age. Aged subjects showed a significant (p less than 0.01) elongation of the to locate the target, a significant (p less than 0.01) decrease in PSV and a significant (p less than 0.01) decrement in SA.

Role of saccadic analysis in the diagnosis of multiple sclerosis in the era of magnetic resonance imaging.

Magnetic resonance imaging (MRI) has recently been recognised as the most sensitive method with which to detect clinically silent lesions in patients affected by multiple sclerosis. Visually guided horizontal saccadic eye movements (SEM) were studied, together with MRI, in 57 multiple sclerosis patients. A very similar sensitivity was found for both MRI (78.2%) and SEM analysis (76.3%). Significant associations between peak saccadic velocity and brain stem signs and between saccadic latency and visual signs were observed.

Computer analysis of saccadic eye movements: assessment of two different carbamazepine formulations.

The central effects of two different formulations of Carbamazepine (CBZ) have been examined by analysis of saccadic eye movements (SEM) in 6 healthy volunteers, who took part in a double-blind, latin-square, placebo controlled study. Both a conventional- and a controlled-release formulation of CBZ produced a significant effect on peak saccadic velocity and saccade accuracy, but only the former affected saccade latency. Computer analysis of SEM confirmed it to be a highly sensitive method for detection of subclinical drug effects on the CNS.

The contribution of saccadic eye movements analysis, visual and auditory evoked responses to the diagnosis of multiple sclerosis.

A number of tests have been used to identify paraclinical evidences of central nervous system (CNS) lesions in multiple sclerosis (MS). The present study was aimed to test and compare the diagnostic value of saccadic eye movements (SEM) analysis, and visual and auditory brain stem evoked responses (VER, ABER) in MS, and to study the correlation between electrophysiologic findings and clinical data. The reference group for epidemiological and statistical analysis was selected from the group of 109 suspected MS patients included in the study. SEM analysis resulted at least as sensitive as VER and ABER. SEM analysis showed good sensitivity and positive predictive value. Saccade latency resulted the most sensitive SEM parameter. Subclinical internuclear ophthalmoparesis resulted highly specific. We suggest that SEM analysis could be included into the electrophysiologic tests for identifying paraclinical evidences of CNS lesions in MS. Correlations between electrophysiologic findings and clinical data are discussed.

Neuroocular side effects of carbamazepine and phenobarbital in epileptic patients as measured by saccadic eye movements analysis.

The effect of carbamazepine (CBZ) and phenobarbital (PB), alone and in association, on the function of specific brain structures was studied in chronically treated epileptic patients by means of saccadic eye movements (SEMs) analysis. The relationship between daily fluctuations of CBZ plasma levels and the occurrence of intermittent side effects was also evaluated. All treatments produced a significant impairment (p less than 0.001) of SEM function as compared with a group of controls. SEM abnormalities appeared to change in relation to daily fluctuation of CBZ plasma levels. When the SEM parameters were considered separately, PB showed a significantly (p less than 0.001) more relevant sedative effect, whereas both drugs appear to produce the same effect on cerebellar and pontine functions. Although impairment of SEM function was most likely far from reaching clinical significance, it represents important information for the clinician.