Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 15 de 15
Filter
Add more filters










Publication year range
1.
Rev Neurol ; 28(5): 453-9, 1999.
Article in Spanish | MEDLINE | ID: mdl-10229956

ABSTRACT

INTRODUCTION: Due to the aging population in developed countries, epidemiological studies show an increasing tendency to the prevalence of epilepsy in the elderly. PATIENTS AND METHODS: During 54 months, we have studied the electroclinical and neuroimaging features in outpatients older than 60, with active epilepsy. Every patient was interviewed by one of the authors. Then, we have reviewed the medical records about the clinical features, EEG and neuroimaging (NI) studies and seizures frequency (SF) outcome. Differences in crude proportions were assessed by chi 2 test for independence by 2 x 2 tables. RESULTS: The study was been performed in 78 patients with 70.3 +/- 7.3 years of mean age at review. Partial seizures were significantly related with an higher SF at onset and, in the series of complex partial seizures was more frequent a temporal EEG topography. There was predominance of men, NI abnormal, symptomatic etiology and SF at onset > or = 1 by day in that patients who started their epilepsy after 60 years. A 51.3% was seizures-free in the last year and in 80% the SF was improved a 50% or more from the beginning. CONCLUSION: A significantly greater percentage of patients remained with seizures in four cases: in those with a SF at onset greater than 1 every day, in those suffering complex partial seizures, in women and in patients with temporal EEG topography.


Subject(s)
Brain/physiology , Electroencephalography , Epilepsy/diagnosis , Aged , Anticonvulsants/therapeutic use , Diagnostic Imaging/methods , Epilepsy/drug therapy , Female , Humans , Male , Middle Aged , Retrospective Studies
2.
J Opt Soc Am A Opt Image Sci Vis ; 16(3): 718-27, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10069057

ABSTRACT

We measured subject performance as a function of luminance for both detection and discrimination of increment stimuli; some were static, and some were arranged to give two-step apparent motion. Our aim was to examine a prediction for the shape of the psychometric function for motion: an accelerating function due to the presence of a multiplicative nonlinearity contained in many low-level motion models. For the tasks with static stimuli we found psychometric function slopes (of log d' versus log luminance plots) between 1.9 and 2.4 in two subjects, as previously reported. For the tasks with apparent motion stimuli in the same range of detectability, however, the slopes are between 1.2 and 1.7. The lower slopes indicate that many low-level motion models are either incorrect or incomplete as currently specified, and changes in nonlinearities and noise placement are discussed.


Subject(s)
Artifacts , Motion Perception/physiology , Psychometrics/methods , Visual Perception/physiology , Discrimination, Psychological/physiology , Humans , Lighting , Nonlinear Dynamics , Photic Stimulation/methods , Sensory Thresholds/physiology , Signal Detection, Psychological/physiology
3.
Rev Neurol ; 27(157): 422-6, 1998 Sep.
Article in Spanish | MEDLINE | ID: mdl-9774812

ABSTRACT

INTRODUCTION AND MATERIAL: During 54 months, we have studied the electro-clinical and neuroimaging features in outpatients with active epilepsy. Each patient was interviewed for one of us. Then, we have reviewed the medical records about both the clinical featuring. EEG and neuroimaging (NI) studies and seizures frequency (SF) outcome. Differences in crude proportions were assessed by chi 2 test for independence by 2 x 2 tables. RESULTS AND CONCLUSIONS: It has been 207 patients with 49 +/- 19.6 years of mean age at review. Partial seizures was significantly related with both a higher SF at onset and politherapy. Also, with a focal EEG distribution but only in case of complex partial seizures. Abnormal NI was significantly more frequent in oldest patients. A greater proportion of patients were in politherapy in four situation: SF at onset > 1 by day, a focal EEG distribution, duration of epilepsy longer than 20 years and age of onset lesser than 60 years. A 37.2% was seizures-free in the last year and in 34% the SF was improved a 50% or more from the beginning. A significantly greater proportion of patients was following with seizures in four cases: when the SF at onset has been > or = 1 by day, being partial seizures, women and having politherapy.


Subject(s)
Electroencephalography , Epilepsy/diagnosis , Tomography, X-Ray Computed , Adult , Anticonvulsants/therapeutic use , Disease Progression , Epilepsy/drug therapy , Female , Humans , Male , Middle Aged , Prognosis
4.
J Opt Soc Am A Opt Image Sci Vis ; 15(8): 2003-11, 1998 Aug.
Article in English | MEDLINE | ID: mdl-9691484

ABSTRACT

We measured motion-detection and motion-discrimination performance for different directions of motion, using stochastic motion sequences. Random-dot cinematograms containing 200 dots in a circular aperture were used as stimuli in a two-interval forced-choice procedure. In the motion-detection experiment, observers judged which of two intervals contained weak coherent motion, the other internal containing random motion only. In the direction-discrimination experiment, observers viewed a standard direction of motion followed by comparison motion in a slightly different direction. Observers indicated whether the comparison was clockwise or counterclockwise, relative to the standard. Twelve directions of motion were tested in the detection task and five standard directions (three cardinal directions and two oblique directions) in the discrimination task. Detection thresholds were invariant with direction of motion, but direction-discrimination thresholds were significantly higher for motion in oblique directions, even at low-coherence levels. Results from control conditions ruled out monitor artifacts and indicate that the oblique effect is relative to retinal coordinates. These results have broad implications for computational and physiological models of motion perception.


Subject(s)
Motion Perception/physiology , Visual Perception/physiology , Anisotropy , Discrimination, Psychological/physiology , Humans , Models, Biological , Photic Stimulation/methods , Sensory Thresholds , Stochastic Processes
6.
Rev Neurol ; 25(140): 518-22, 1997 Apr.
Article in Spanish | MEDLINE | ID: mdl-9172909

ABSTRACT

INTRODUCTION: In complex partial crises (CPC) some characteristics of the way in which they occur may be helpful in localizing the focus of origin in the cerebral cortex. Thus, the appearance of any kind of status epilepticus will not predominate depending on the origin of the epileptic focus, but the complex partial state will be rare when the origin is temporal and more frequent when the origin is frontal. The appearance of CPC in a cluster form is, on the other hand, characteristic of crises originating in the frontal lobe. MATERIAL AND METHODS: We review the clinical history of 151 epileptics with CPC, evaluating the way in which the crises appear, together with other clinical data. We define the start of the crisis in a specific lobe, when this was the site of maximum voltage of the epileptic anomaly or of maximum phase opposition. RESULTS: 10% of the patients showed grouping of their CPC; in the remainder the appearance was isolated, 15% showed status epilepticus at some point in their illness. We found a statistical difference when relating this to the anomalous topography of the EEG; between 15% and 42% more patients with status epilepticus were counted when the topography of the anomaly in the EEG was extratemporal. There was also between 37.2% and 76.4% more patients with cluster crises in the cases with an extratemporal focus.


Subject(s)
Epilepsy, Complex Partial/diagnosis , Status Epilepticus/diagnosis , Adolescent , Adult , Aged , Cerebral Cortex/physiopathology , Electroencephalography , Epilepsy, Complex Partial/physiopathology , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Status Epilepticus/physiopathology , Tomography, X-Ray Computed
7.
Vision Res ; 36(15): 2297-302, 1996 Aug.
Article in English | MEDLINE | ID: mdl-8776494

ABSTRACT

We measured the relative efficiency for motion and position discriminations of brief, localized spot stimuli with a technique that makes no assumptions about sites of noise or information loss in the visual system. In one task, the observer had to discriminate whether an increment was located at one (left) or another (right) closely spaced spots. In the other task, the observer had to discriminate two successive brief increments of the left spot from a left spot increment followed by a right spot increment. Ideal observer theory predicts identical performance on the two tasks. Observers' thresholds, however, were significantly lower in the motion task at all intervals between flashes (ISIs) less than 60 msec in one observer and all ISIs less than 150 msec in two other observers (P < 0.01, t-test). We conclude that this apparent motion stimulus is seen more efficiently than a non-moving stimulus, and that the higher efficiency may be due to use of a motion sensitive channel in addition to independent position sensitive channels.


Subject(s)
Motion Perception/physiology , Discrimination, Psychological , Humans , Lighting , Male , Optical Illusions/physiology , Psychophysics , Sensory Thresholds/physiology , Time Factors
8.
Rev Neurol ; 24(132): 960-3, 1996 Aug.
Article in Spanish | MEDLINE | ID: mdl-8755357

ABSTRACT

Neuro-imaging studies (NI) in patients with complex partial seizures (CPC) demonstrate the epileptogenicity of a more or less localized underlying lesion. Correlation with the topography of the EEG focus permits affirmation of the origin. We analyze anomalies on NI and on the EEG of 151 patients with CPC. The EEG was abnormal in 128 and showed a unilateral epileptic focus in 117. NI was focal and unilateral in 72 of the 102 abnormal cases. Topographic correlation was 78.5%. This close correlation in our series makes us consider the localized lesions to be the probable aetiological factor.


Subject(s)
Brain Mapping , Brain/physiopathology , Electroencephalography , Epilepsy, Complex Partial/diagnosis , Epilepsy, Complex Partial/physiopathology , Adult , Epilepsy, Complex Partial/etiology , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged
9.
Rev Neurol ; 24(131): 820-4, 1996 Jul.
Article in Spanish | MEDLINE | ID: mdl-8681193

ABSTRACT

With the appearance of MR, a great advance has been made in the study of the aetiology of epilepsy. This technique can show anomalies not detected in CT scans, obtain images of multiple planes, improve the differentiation of cerebral tissues and allow improved visualization of the temporal lobe, making it very useful in the study of patients with complex partial crises (CPC). We studied 151 epileptics with CPC by means of CT scan and MR in all cases; the anomolous topography was the same in all cases, but the diagnosis was not. In patients with a previously normal CT scan, on MR anomalies were detected in 24 cases. We found a statistical differences on evaluation of the MR anomaly depending on whether the CT scan was normal or abnormal. Statistical differences were also found when there were a greater number of anomalies on MR depending on the frequency of crises at the onset of the disorder.


Subject(s)
Epilepsy, Complex Partial/diagnosis , Epilepsy, Complex Partial/etiology , Magnetic Resonance Imaging , Tomography, X-Ray Computed , Adolescent , Adult , Aged , Brain/physiopathology , Epilepsy, Complex Partial/physiopathology , Female , Humans , Male , Middle Aged
10.
J Am Coll Cardiol ; 24(4): 928-33, 1994 Oct.
Article in English | MEDLINE | ID: mdl-7930226

ABSTRACT

OBJECTIVES: This study was designed to characterize the clinical, echocardiographic and angiographic findings in patients who have regional wall motion abnormalities predictive of coronary artery disease on dobutamine stress echocardiograms, although coronary angiography reveals no critical stenoses. BACKGROUND: The specificity of dobutamine stress echocardiography has been reported to be lower than its sensitivity; the sources of false positive findings on dobutamine stress echocardiograms have not been previously defined. METHODS: Clinical and echocardiographic characteristics were retrospectively reviewed for patients who had both a dobutamine stress echocardiogram indicative of coronary artery disease on the basis of wall motion abnormalities and < 50% stenoses reported on coronary angiography performed within 6 weeks of the echocardiogram. A 16-segment model was used to perform wall motion scoring. Angiograms were independently reviewed, and stenosis severity was quantified with the use of digital calipers. RESULTS: Thirty-nine (11.4%) of 342 studies met criteria for false positive test results, which occurred predominantly in women (72%, p < 0.001). Regional wall motion abnormalities were evident more often in the posterior circulation (62%), and 65% of them were limited to the basal segments. Twelve (28%) of 43 wall motion abnormalities were associated with coronary stenoses of at least intermediate grade (lumen diameter 40.3% to 68.1%). Abnormalities confined to basal segments of the posterior circulation were unlikely to have associated coronary lesions (p = 0.03). CONCLUSIONS: False positive findings on dobutamine stress echocardiograms tend to involve small wall motion abnormalities that are frequently located in basal segments of the posterior myocardial circulation. Approximately one third of false positive results occurred in patients with intermediate-grade coronary stenoses, and these studies may reflect true inducible ischemia. Additional sources of false positive study results may include poor endocardial visualization and abnormal motion due to tethering to the fibrous skeleton of the heart. Altered echocardiographic diagnostic criteria may be appropriate for small wall motion abnormalities confined to basal segments of the posterior circulation.


Subject(s)
Coronary Angiography , Coronary Disease/diagnostic imaging , Dobutamine , Echocardiography , Adult , Aged , Aged, 80 and over , Constriction, Pathologic/diagnostic imaging , Constriction, Pathologic/physiopathology , Coronary Disease/physiopathology , Exercise Test , False Positive Reactions , Female , Humans , Male , Middle Aged , Myocardial Contraction , Predictive Value of Tests , Retrospective Studies , Sensitivity and Specificity
12.
Neurologia ; 7(1): 10-4, 1992 Jan.
Article in Spanish | MEDLINE | ID: mdl-1596398

ABSTRACT

The authors evaluated the type of neurological involvement existing in patients with Behçet's syndrome over a 10 year period. Nine patients presenting several bouts with neurological symptomatology were studied with headache being clinically predominant followed in order of frequency by sensitive and/or motor ictal pictures. Suspected localization was both hemispheric and brain stem. No diagnostic test was able to clear up the origin of the lesions in the first stages of the disease, however the authors were able to observe, upon performing visual and/or brain stem evoked potentials and nuclear magnetic resonance at the time of the control, that several asymptomatic patients showed alterations in both tests. Thus, the value of the above mentioned tests must be emphasized in the follow up and control of neuro-Behçet's disease.


Subject(s)
Behcet Syndrome/complications , Headache/etiology , Hemiplegia/etiology , Adult , Behcet Syndrome/pathology , Behcet Syndrome/physiopathology , Brain/pathology , Brain Ischemia/etiology , Brain Ischemia/pathology , Evoked Potentials , Female , Headache/pathology , Hemiplegia/physiopathology , Humans , Magnetic Resonance Imaging , Male , Meningitis, Aseptic/etiology , Meningitis, Aseptic/pathology , Vision Disorders/etiology , Vision Disorders/physiopathology
15.
Presse Med ; 14(14): 773-6, 1985 Apr 06.
Article in French | MEDLINE | ID: mdl-3158891

ABSTRACT

The indications for endomyocardial biopsy were evaluated from 116 consecutive cases. The diagnostic value of this invasive but well tolerated procedure was in agreement with data from the literature. An accurate diagnosis, unforseeable in 8% of the patients, was established in 12%. The diagnosis of apparently primary myocardiopathy with ventricular dilatation was confirmed in 45 out of 59 cases; there were 3 cases of myocarditis, 3 cases of restrictive cardiopathy (haemochromatosis, fibroplastic endocarditis) and 1 case of hypertrophic cardiopathy. No tissue abnormality was noted in 6 cases. An accurate diagnosis was obtained by biopsy in 1 case of "eosinophilic lung" without overt cardiac involvement. In malignant diseases treated with anthracyclines in doses reaching maximal theoretical total dosage (30 patients), severe tissue lesions were present in 10% of the cases, incipient haemochromatosis in 16.6% and subendocardial fibrosis in 3.3%. However, total doses of up to 600 mg/m2 could be administered to 90% of the patients. Myocardial lesions could be demonstrated in 1 of 2 patients with collagen disease. Endomyocardial biopsy therefore seems to be justified in myocardiopathies with ventricular dilatation, in some collagen diseases with a tendency to cardiac involvement and to monitor treatment with anthracyclines in total doses higher than the theoretical maximum dosage.


Subject(s)
Cardiomegaly/pathology , Cardiomyopathies/pathology , Myocardium/pathology , Adolescent , Adult , Aged , Antibiotics, Antineoplastic , Biopsy , Female , Humans , Male , Middle Aged , Naphthacenes/administration & dosage , Naphthacenes/adverse effects
SELECTION OF CITATIONS
SEARCH DETAIL
...