Biomedical subjects

M Falautano

Publications and source records attributed to M Falautano.

5 recordsLinked to original sources

PubMed2000

Electroencephalographic coherence analysis in multiple sclerosis: correlation with clinical, neuropsychological, and MRI findings.

OBJECTIVE: To explore functional corticocortical connections in multiple sclerosis by means of coherence of the EEG, and to evaluate their correlations with the degree of cognitive impairment and with brain lesion load assessed by MRI. METHODS: EEG coherence was studied from 28 patients with clinically definite multiple sclerosis. Ten minutes of resting EEG were recorded with 20 scalp electrodes, with binaural reference. FFT power and coherence were calculated in artifact free epochs of 1 second and compared with values from 22 control subjects of comparable age and sex distribution. Patients also underwent MRI (n=27) and neuropsychological examination (n=21). RESULTS: Compared with controls, patients with multiple sclerosis showed increased theta power in the frontotemporal-central regions (p<0.005). theta Band coherence was decreased between homologous areas (p<0.02). alpha Band coherence was decreased both in the local and long distance connections (p<0.0005). These findings were most striking both in patients with high MRI subcortical lesion load and in patients with cognitive involvement. A significant correlation was found between interhemispheric theta (p=0.02) and alpha (p=0. 017) and anteroposterior alpha (p=0.013) coherence and subcortical MRI lesion load, but not with exclusively periventricular lesion load. CONCLUSIONS: These findings support the hypothesis that cognitive impairment in multiple sclerosis is mostly dependent on involvement of corticocortical connections related to demyelination and/or axonal loss within the white matter immediately underlying the cortex.

Adult↗

PubMed2000

Neuropsychological impairment in multiple sclerosis patients: the role of (juxta)cortical lesion on FLAIR.

In this study we evaluated the correlation between neuropsychological impairment (measured with the Brief Repeatable Battery Neuropsychological Tests) and (juxta)cortical lesions detected with FLAIR and the relative sensitivity of the FLAIR sequence compared to spin-echo MRI sequences in detecting (juxta)cortical MS lesions. A total of 39 patients with definite MS were evaluated by MRI with a conventional and fast spin echo sequence and fast FLAIR sequence, and neuropsychological tests of the Brief Repeatable Battery Neuropsychological tests were performed. The Z-score of all subtests were used to calculate a Cognitive Impairment Index. The results show that a high number of (juxta)cortical lesions is detected with thin slice FLAIR (30% of all lesions seen). This percentage was not superior to spin-echo, reflecting the thin slice thickness (3 mm) we used. The lesions detected with FLAIR were to a certain degree different ones than the lesions detected with the other techniques. While the number of non-cortical lesions correlated with the expanded disability status scale (r=0.32, P=0.045), the number of (juxta)cortical lesions detected with the FLAIR showed a correlation (r=0.34, P=0.035) with the Cognitive Impairment Index. Our study underlines the high number of (juxta)cortical lesions in MS and the value of thin slice FLAIR sequence to detect such lesions with MRI. It also stresses the importance of (juxta)cortical lesions on determining neuropsychological impairment. Multiple Sclerosis (2000) 6 280 - 285

Adult↗

PubMed1999

A multiparametric MRI study of frontal lobe dementia in multiple sclerosis.

Previous studies achieved conflicting results when correlating magnetic resonance imaging (MRI) abnormalities and cognitive impairment in multiple sclerosis (MS) patients. Recently, the estimation of MS lesion load on T1-weighted images and the analysis of magnetization transfer ratio (MTR) histograms, increased the degree of the correlation between physical disability and MRI findings in MS. We assessed the relationship of conventional and non-conventional MRI-derived measures with frontal lobe dementia in MS. Dual echo, T1-weighted and MT MRI scans of the brain were obtained in 11 MS patients with and in 11 without frontal lobe dementia, matched for age, sex, education and disability. Total (TLL) and frontal (FLL) lesion loads were assessed from T2- and T1-weighted scans. MTR histogram analysis was performed for the whole brain, the frontal lobe and the cerebellum. Median TLL and FLL were significantly higher in cognitively impaired patients on both T2- and T1-weighted scans. The MRI measure that better discriminated the two groups of patients was T1-weighted TLL (median values were 19.1 ml for demented and 1.9 ml for non-demented patients, P=0.006). Average MTR, peak height and location of overall brain and frontal lobe histograms were significantly lower for cognitively impaired than for cognitively intact patients (P values ranged from 0.0001 to 0.001). Cerebellar MTR histogram metrics did not significantly differ in patients with and without cognitive decline. The presence of cognitive decline in MS is associated with the extent and pathological severity of brain MRI abnormalities.

Dementia↗

PubMed1999

Cognitive function in primary progressive and transitional progressive multiple sclerosis: a controlled study with MRI correlates.

The relative rarity of primary progressive (PP) and transitional progressive (TP) multiple sclerosis has meant that little documentation of cognitive function in such patients is currently available. The aim of this study was to investigate the cognitive skills of patients with PP and TP multiple sclerosis relative to matched healthy controls, and to examine the relationship of this impairment to MRI parameters. Sixty-three patients (43 PP, 20 TP) were individually matched with healthy controls, who undertook the same cognitive tasks as the patient group. The neuropsychological assessment comprised Rao's brief repeatable battery, a reasoning test, and a measure of depression. Patients also underwent T1- and T2-weighted brain MRI. These patients were taken from a larger cohort (158 PP, 33 TP) in whom it had been demonstrated that the re were no significant differences between the mean scores of the PP and TP groups on any of the cognitive variables. The 63 patients were therefore taken as one group for comparison with the healthy controls. These patients performed significantly worse than the controls in tests of verbal memory, attention, verbal fluency and spatial reasoning. An impairment index was constructed and applied to the patient data. This correlated modestly with T2-lesion load (r = 0.45, P = 0.01), T1-hypointensity load (r = 0.45, P = 0.01) and cerebral volume (r = -0.35, P = 0.01). Thus, PP and TP multiple sclerosis patients demonstrate significant cognitive dysfunction when compared with matched healthy controls. The relationship between this impairment and MRI parameters is moderate, suggesting that cognitive dysfunction in PP and TP multiple sclerosis has a complex and multifactorial aetiology, which is not adequately explained by pathology as demonstrated on conventional MRI.

Adult↗

PubMed1998

Relation between MR abnormalities and patterns of cognitive impairment in multiple sclerosis.

OBJECTIVE: This study correlated the extent of abnormalities detected by different magnetic resonance imaging (MRI) techniques [proton density (PD)-weighted, T1-weighted, and magnetization transfer imaging (MTI)] with the overall cognitive, frontal lobe, and memory impairments in patients with MS. PATIENTS: There were 30 clinically definite MS patients, with different disease courses. EXCLUSION CRITERIA: psychoactive/steroid treatments, mood disorders, acute relapse phase. MAIN OUTCOME MEASURES: Neuropsychological test results. Total (TLL) and frontal (FLL) lesion loads assessed from PD-weighted, T1-weighted (22 patients), and MTI (22 patients) MRI scans. Average lesion MT ratios (MTR) and analysis of the MTR histograms from brain tissue axial slabs on MTI scans. RESULTS: Patients with frontal lobe deficits (n=15) or memory impairment (n-17) had a higher TLL on PD scans (p=0.04 and p=0.01, respectively). Patients with frontal lobe deficits had higher FLL on PD scans (p=0.01) and TLL on MTI (p=0.03) scans. No significant relationships between the extent of T1-weighted lesion loads and the presence of any neuropsychological impairment. Mean MTR of both MS lesions and whole brain tissue was lower in patients with frontal lobe impairment (p=0.04). MRI lesion loads correlated significantly with some neuropsychological test scores. CONCLUSIONS: Lesion loads on PD-weighted MRI and MTI-derived measures are associated with cognitive decline in MS patients. Overall macroscopic and microscopic brain damage is more important than the corresponding regional brain disease in determining deficits of selective cognitive domains.

Adult↗