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F Coret

Publications and source records attributed to F Coret.

17 recordsLinked to original sources
PubMed2006

Accurate quantification methods to evaluate cervical cord atrophy in multiple sclerosis patients.

OBJECT: Automatic accurate measurement techniques are needed to increase reproducibility in the quantification of cervical cord area (CCA) with magnetic resonance (MR) imaging in the assessment of central nervous system (CNS) atrophy in multiple sclerosis (MS) patients. MATERIALS AND METHODS: Two segmentation methods were implemented: (1) spatial mean brightness level estimation (SMBLE), and (2) partial-volume modeling (PVM). These were evaluated with the inclusion of spinal cord inclination and/or partial-volume-effect corrections. An averaged manually segmented set was considered as reference. Thirty MR studies were used to compare the different methods. A set of 15 MS patients and 15 control subjects within a two-year longitudinal study were used to evaluate cord atrophy with the best method. Statistical evaluation was made by using an intraclass correlation coefficient and Bland-Altman comparisons. RESULTS: Partial-volume modeling with spinal cord inclination correction and partial-volume spinal-cord contour contribution estimation was the most accurate method. The longitudinal test showed a 4% decrease in CCA in MS patients with no significant reduction in control subjects. CONCLUSION: The automatic PVM cord-segmentation approach, taking into consideration the spinal-cord inclination and partial-volume treatment, provides reproducibility and increased accuracy in the evaluation of cord atrophy, allowing the monitoring of changes in MS patients.

Adolescent↗
PubMed2006

[Atypical clinicoradiological course in a case panancephalic variant of Creutzfeldt-Jakob].

INTRODUCTION: Creutzfeldt-Jakob disease (CJD) is the most frequent of the human transmissible spongiform encephalopathies. Pathogenic mechanisms of CJD are still unknown. Sporadic CJD, the most habitual, is clinically characterized by rapidly progressive dementia, myoclonia and ataxia. Panencephalic variant CJD, typically from Japan, is characterized by extensive involvement of the cerebral white and gray matter. International interest has grown from more than one decade ago in relation to the diagnosis of new variant (vCJD). New protocols of MR imaging have contributed to the early diagnosis of CJD with specific signs. CASE REPORT: We report a case of panencephalic CJD, with atypical clinical presentation and unusual MR imaging findings. DISCUSSION: Our patient developed visual and psychiatric symptoms. Brain MR imaging showed extensive white matter lesions in posterior parietal lobe and occipital regions, which disappeared after steroid treatment. The most characteristic radiological sign for sporadic CJD is the high signal intensity of the basal ganglia, for vCJD the pulvinar sign and, for panencephalic CJD the presence of periventricular white matter lesions, with tendency to the spread when the disease progress. In serial MR imaging studies of our patient, we could see how typical signs were appearing. However, the complete and unusual resolution of the original white matter lesions makes us to think about a possible inflammatory component, in some time in the evolution of white matter damage.

Adult↗
PubMed2003

Evidence of Wallerian degeneration in normal appearing white matter in the early stages of relapsing-remitting multiple sclerosis: a HMRS study.

OBJECTIVE: Wallerian degeneration in normal appearing white matter in early relapsing-remitting multiple sclerosis (RRMS), and its correlation with the number of relapses and disease duration. Background Recent pathological studies have demonstrated Wallerian degeneration in normal appearing white matter (NAWM) in multiple sclerosis (MS), in established RRMS, and in chronic MS. However, the presence of Wallerian degeneration early in the disease and its correlation with relapse and with disease duration has not been studied. METHODS: We performed proton magnetic resonance spectroscopic imaging in 21 MS patients, and 4 healthy controls, age and gender matched, aged under 45 years, with a maximum of 4 years since first bout, and an EDSS score of less than 3.0. N-acetyl-aspartate (NAA) (an index of axonal integrity) was measured in the NAWM from the pons and the cerebellar peduncles. RESULTS: We observed that the NAA levels were abnormally low in the NAWM in the early RRMS patients (p = 0.04, Student's t-test). The decrease in the NAA concentration correlated with disease duration in the two areas studied (p = 0.03 for pons and p = 0.04 for cerebellar peduncle); and with the number of previous relapses (Pearson's correlation = -0.582, p < 0.002). CONCLUSION: Wallerian degeneration measured by the NAA concentration at pons and cerebellar peduncles is present early in the disease and correlates with the number of relapses and disease duration.

Adolescent↗
PubMed2002

High clinical inflammatory activity prior to the development of secondary progression: a prospective 5-year follow-up study.

OBJECTIVE: To study if there are different patterns of clinical activity--measured by the annual exacerbation rate (AER)--among relapsing-remitting multiple sderosis (RRMS), "early" secondary multiple sclerosis (SPMS) and "late" SPMS. METHODS: A prospective 5-year follow-up study in 80 MS patients has been carried out, calculating the AER and the mean expanded disability status scale (EDSS) change rate (MCR). RESULTS: A significant difference on the AER, among RRMS, early SPMS and late SPMS, has been found. CONCLUSIONS: The SPMS has a high clinical inflammatory activity before and during its transformation from a RRMS.

Adult↗
PubMed1998

[A risk of developing multiple sclerosis following an outbreak of optic neuritis during a mean follow-up of 4.5 years].

OBJECTIVE: The current study was designed to determine the risk of developing clinically definite multiple sclerosis (CDMS) after an isolated idiopathic optic neuritis (ON). PATIENTS AND METHODS: We retrospectively studied 28 patients (range from 18-45 years) who presented a unilateral acute ON between 1 st April and 31 st December. We excluded optic neuropathy of other causes, a previous diagnosis of MS or systemic diseases associated with ON. Patients underwent brain MRI, visual evoked potentials (VEPs), somatosensory evoked potentials (SEPs) and brainstem auditory evoked potentials (BAEPs). The mean interval between ON onset and MRI was 3.1 months. 24 patients were treated with corticosteroids in different ways: oral prednisone (14) and intravenous methylprednisolone (10). Mean duration of the follow-up was 4.5 years in 26 patients. RESULTS: Brain MRI detected white matter areas with increased signal in 10 of 25 patients (40%). Eight (30%) had bilateral anormalities on VEP, while SEPs and BAEPs revealed anormalities in one patient (5.5%). Two out 26 patients (7.7%) developed CDMS; one was treated with oral prednisone and the other with intravenous corticosteroids. No patients with normal MRI developed MS compared to 20% of patients with lesions on initial brain MRI. The only patient with abnormal SEPs and BAEPs did not develop MS. CONCLUSIONS: We found in our population low rate of developing CDMS with higher risk for those ON with abnormalities on initial brain MRI.

Adolescent↗
PubMed1997

[Predictive value of the study of cerebro-spinal fluid in neurological diseases. Discriminant analysis of 733 cases].

INTRODUCTION: The study of cerebrospinal fluid (CSF) gives very valuable data for the diagnosis of certain neurological disorders. Objective. To discover the discriminative value of different tests and their usefulness in the study of neurological disorders. MATERIAL AND METHODS: Discriminative multivariate analysis was used for the group of parameters obtained from study of CSF and serum in a sample of 733 patients. BO was included, CSF cytobiochemical data and five of the equations used for calculation of the synthesis of intrathecal IgG. RESULTS: The best discriminative function was expressed as the intrathecal IgG with normal BHE. The formula of Tourtellotte was noteworthy for overestimation of the synthesis of intrathecal IgG when the albumin index indicated BHE rupture. Prospective reclassification of the 733 cases showed that these tests are well worthwhile to rule out immunologically mediated disorders (93% of the cases were correctly reclassified); they suggest the diagnosis in multiple sclerosis (66% correctly reclassified) and give very poor reliability when trying to distinguish between inflammatory infectious processes. CONCLUSIONS: In spite of their undoubted use in supporting the clinical diagnosis, the tests used for study of the synthesis of IgG, even complemented by cytobiochemical examination of the CSF, are not in themselves sufficient for use as a discriminative test in the differential diagnosis of neurological processes.

Albumins↗
PubMed1993

[Intrathecal synthesis of IgG: comparative study of its determination with 5 different equations, in 733 neurologic patients].

In order to find out the degree to which rupture of the blood-brain barrier (BBB) could influence the diagnostic effectiveness of five equations used to determine the intrathecal synthesis of IgG, a comparative study was performed with results from 733 patients with different neurological processes either related to an immune response (PNI) or not (PNNI). Rupture of the BBB was determined by a quotient of cerebrospinal fluid (CSF)/serum albumin (COA) higher than that obtained in the control group. When the BBB was retained, there was no clear superiority of one formula over another, but an altered BBB was the conditioning factor in the divergence. The extended Index was the least influenced by the rupture of the BBB, while Tourtellotte's equation was the most affected. In agreement with the clinical information data, the IgG Index was the most sensitive equation, while the extended Index was the most specific.

Blood-Brain Barrier↗
PubMed1990

[Findings of computed tomography in the acute form of Marchiafava-Bignami disease].

We report a case of Marchiafava-Bignami's disease with acute evolution. Pathological examination was carried out and a cavitary lesion with discontinuous longitudinal extension was found throughout the corpus callosum. CT had shown a narrow hypodense area symmetrically localized just anterior to the frontal horns of the lateral ventricles, corresponding to the genus of the corpus callosum. The literature is reviewed, the anatomical-radiological correlations are discussed, and the possibility of the diagnosis of this condition during life is commented.

Acute Disease↗
PubMed1989

[The presence of oligoclonal bands in the cerebrospinal fluid in various neurologic diseases].

The polyacrylamide gel electrophoresis of spinal fluid from 488 patients suffering neurological diseases and from a control group are reviewed. One hundred and eleven cases (22.7%) showed oligoclonal bands (OB). The highest percentage of OB appeared in the group of patients with definite multiple sclerosis (84%), followed by those with probable multiple sclerosis (46%) and inflammatory infectious diseases (43%); the group of patients with a possible multiple sclerosis (7%), vascular malignancies (11%) and other diseases (4%) showed a lower incidence of OBs. No OBs were found in groups of patients with degenerative diseases, dementia or the control group. These results confirm the great usefulness of this test to support the diagnosis of multiple sclerosis, although it also shows that it is not a specific test so it should always be evaluated within a clinical context.

Electrophoresis, Polyacrylamide Gel↗
PubMed1989

[Abnormal movements of vascular origin].

Three patients with hemichorea and ten with dystonia of vascular origin are reported. Five were secondary to ischemic infarcts, two to lacunar infarcts, three to intraparenchymal hematoma, and in the remaining three the type of lesion could not be determined. The patients with chorea, as opposed to those with dystonia, presented abruptly immediately after the stroke, and had a regressive evolution and good therapeutic response. The type of dyskinesia was not useful to identify the precise localization of the lesion or to determine its nature. In addition, in 5 patients multiple lesions were found and 5 had release of archaic reflexes or cortical atrophy in CT; this shows the importance of the overall functional impairment and focal lesions in the genesis of dyskinesia. There were sensory deficits in 7 patients. In 2 patients lesions were not found in the CT in spite of the presence of previous hemiparesis; this suggests that this technique has limitations to discover focal cerebral lesions in patients with focal or hemicorporal dyskinesia.

Adult↗
PubMedDate not supplied

[A critical review of the current pathogenesis of multiple sclerosis and possible future trends].

INTRODUCTION: Multiple sclerosis (MS) is a disorder in which the pathogenesis is not clearly understood, but where the disability caused and its progression determine the seriousness of the condition. At present, inflammation due to T lymphocytes is thought to be the cause of the clinical features and resulting disability. The main feature is demyelination, but it has not been possible to show by immunology studies, neuroimaging studies or therapeutic trials that the binomial inflammation-demyelination correlates with the disability. Therefore other possibilities of pathogenesis which provide a better explanation for the clinical findings in MS may be considered. DEVELOPMENT: We may start with the hypothesis of the existence of gliotoxic and neurotoxic factors in a patient with MS. These, by means of electrical inhibition mechanisms, autoimmune phenomena and loss of the normal neurone-oligodendrocyte-astrocyte relationship, or a non-specific immune response may give place to inflammation with secondary demyelination on the one hand and to axonopathy with alterations in the mechanisms of remyelination due to alterations in the signals between the axon and the oligodendrocyte on the other. CONCLUSIONS: When these three factors are considered, a better explanation is found for the factors which determine the progression of the disability, exhaustion of the inflammatory response, deficient remyelination and the poor correlation between demyelination and the progression of the disease. At the same time, new possibilities for approaches to the treatment and investigation of MS appear.

Astrocytes↗
PubMedDate not supplied

[A study of various scales of fatigue and impact on the quality of life among patients with multiple sclerosis].

OBJECTIVES: To explore fatigue in multiple sclerosis and evaluate the specificity of three fatigue scales in this condition: the fatigue severity scale, the specific fatigue scale and the fatigue impact scale. MATERIAL AND METHODS: We sent out 60 questionnaires with the three scales and the quality of life scale, the Nottingham Health Profile, to patients with multiple sclerosis as clinically defined by Poser's criteria. Answers were received to 58 questionnaires and the data correlated by Sperman's correlation and the Student t test, with demographic variables (age, age of onset and sex) and clinical variables (clinical form, time the disease was present, period of time since the previous episode and Kurtzke scale (EDSS). RESULTS: Fatigue was present in 78% of the patients. There was correlation between fatigue severity scale and EDSS, pyramidal function, cerebellar function, the period of time the illness was present and the clinical form. We found that the specific fatigue scale is independent of EDSS. The fatigue impact scale was correlated with the EDSS apart from the questions concerning cognitive function. CONCLUSIONS: Fatigue is a common symptom of multiple sclerosis which has an independent effect on cognitive function. It is also related to involvement of the pyramidal and cerebellar systems, and depends on the degree of disability and time the disease has been present. The specific fatigue scale is a good tool for exploration of this symptom of multiple sclerosis.

Cognition Disorders↗
PubMedDate not supplied

[Disseminated encephalomyelitis. A study of 5 cases].

Five cases of acute disseminated encephalomyelitis (ADE) with a follow-up longer than 5 years are presented. The clinical picture, CT images, MR and laboratory tests, specially LCR and evoked potentials presented in a variable form. In two cases the symptoms were preceded by viral infection. The course was acute in one case while the other four evolved in a subacute form during weeks. In two patients a pseudotumoral pattern was observed in the CT and MR images leading to difficulties in the diagnosis. Clinical improvement was accompanied by a partial resolution of the lesions. Steroid treatment improved symptomatology in all the cases. Knowledge of this process may avoid the unnecessary practice of other, more aggressive tests.

Adolescent↗