ABSTRACT
BACKGROUND: The accrual of brain focal pathology is considered a good substrate of disability in relapsing-remitting multiple sclerosis (RRMS). However, knowledge on long-term lesion evolution and its relationship with disability progression is poor. OBJECTIVE: The objective of this paper is to evaluate in RRMS the long-term clinical relevance of brain lesion evolution. METHODS: In 58 RRMS patients we acquired, using the same scanner and protocol, brain magnetic resonance imaging (MRI) at baseline and 10±0.5 years later. MRI data were correlated with disability changes as measured by the Expanded Disability Status Scale (EDSS). RESULTS: The annualized 10-year lesion volume (LV) growth was +0.25±0.5 cm(3) (+6.7±8.7%) for T2-weighted (T2-W) lesions and +0.20±0.31 cm(3) (+11.5±12.3%) for T1-weighted (T1-W) lesions. The univariate analysis showed moderate correlations between baseline MRI measures and EDSS at 10 years (p < 0.001). Also, 10-year EDSS worsening correlated with LV growth and the number of new/enlarging lesions measured over the same period (p < 0.005). In the stepwise multiple regression analysis, EDSS worsening over 10 years was best correlated with the combination of baseline T1-W lesion count and increasing T1-W LV (R = 0.61, p < 0.001). CONCLUSION: In RRMS patients, long-term brain lesion accrual is associated with worsening in clinical disability. This is particularly true for hypointense, destructive lesions.
Subject(s)
Brain/pathology , Multiple Sclerosis, Relapsing-Remitting/complications , Multiple Sclerosis, Relapsing-Remitting/pathology , Adult , Disability Evaluation , Disease Progression , Female , Humans , Longitudinal Studies , Magnetic Resonance Imaging , Male , Time FactorsABSTRACT
OBJECT: Simultaneous EEG-fMRI recordings allow the identification of haemodynamic changes induced by neuronal activity during ictal or interictal epileptiform events (IEDs). We evaluated the reproducibility of continuous EEG-fMRI (cEEG-fMRI) in patients with focal epilepsy. MATERIALS AND METHODS: We studied 15 patients with focal epilepsy (8 cryptogenic and 7 symptomatic) and frequent interictal abnormalities. Each patient underwent two cEEG-fMRI acquisitions (runs) in the same day (session) and 8 patients repeated the examination after one month. cEEG-fMRI reproducibility was defined by the existence of partially overlapping clusters between activation maps obtained from different runs. RESULTS: We detected IEDs in 40 out of 46 EEG-fMRI runs and a related significant BOLD-response in all 40 runs. A prevalent positive BOLD response was detected in 12 patients and a prevalent negative response in 3 subjects. Statistical maps included a mean of 10 significant clusters. Nearly 30% of clusters were reproducible in both intrasession and intersession comparisons, with a mean overlap of 30%. Reproducibility did not differ between positive and negative BOLD-responses. DISCUSSION: Among the reproducible clusters, those with the highest percentage of overlap were concordant with the EEG electric field in all patients and they were localized in the same lobe as the brain lesion in patients with symptomatic epilepsy. We hypothesize that reproducible clusters could be more consistently related to the irritative zone than non-reproducible ones. CONCLUSION: The evaluation of cluster reproducibility could improve our knowledge of IED-related BOLD response. Moreover, it could enhance the reliability of cEEG-fMRI to identify the irritative zone in focal epileptic patients.
Subject(s)
Electroencephalography/methods , Epilepsies, Partial/diagnosis , Magnetic Resonance Imaging/methods , Oxygen/blood , Oxygen/metabolism , Adult , Brain/physiopathology , Brain Mapping/methods , Epilepsies, Partial/blood , Epilepsies, Partial/pathology , Female , Humans , Image Processing, Computer-Assisted , Male , Middle Aged , Reproducibility of ResultsABSTRACT
Blood oxygenation level dependent (BOLD) response related to interictal activity was evaluated in a patient with post-traumatic focal epilepsy at repeated continuous electroencephalogram (EEG)-functional magnetic resonance imaging examinations. Lateralized interictal EEG activity induced a main cluster of activation co-localized with the anatomical lesion. Spreading of EEG interictal activity to both frontal lobes evoked bilateral clusters of activation indicating that topography of BOLD response might depend on the spatial distribution of epileptiform activity.