Motor dysfunction correlates with frontal white matter ischemic changes in patients with leukoaraiosis.

UNLABELLED: Objectives. To test the relation between white matter lesions (WML) location and physical performance, in aged patients. Methods. SUBJECTS: 29 patients (17 males), aged >65 (mean age 72.6 ± 5.2), with leukoaraiosis. WML was quantified with a visual scale; Apparent Diffusion Coefficient (ADC) was measured bilaterally in frontal periventricular lesioned white matter and frontal and parieto-occipital normal appearing white matter (NAWM). Motor performance was studied using the Short Physical Performance Battery (SPPB), single leg stand time, finger tapping and grooved pegboard tests (GPT). Results. There were significant correlations between the frontal region visual scale scores and SPPB chair stands (r = -0.379; P = .039) and Grooved Pegboard (r = 0.393; P = .032); frontal NAWM ADC values and SPPB standing balance (r = -0.450; P = .014) and SPPB 4 meter walk (r = -0.379; P = .043). Conclusion. Frontal WML are negatively related to motor performance in patients with leukoaraiosis. DWI results suggest that this may be true even for NAWM.

The electroclinical-imagiological spectrum and long-term outcome of transient periictal MRI abnormalities.

The electroclinical-imagiological spectrum and long-term outcome of transient periictal MRI abnormalities (TPMA) remains largely unclear. This prompted us to perform a prospective observational cohort study, including electroencephalography (EEG) and multi-sequence MRI, in 19 consecutive patients (8 female, mean age 51.7 years) with TPMA induced by convulsive and non-convulsive status epilepticus (n=14) or isolated seizures. TPMA were associated with focal, lateralized or diffuse EEG abnormalities, and were mostly focal unilateral and cortico-subcortical (n=11), less frequently cortically restricted, bilateral, hemispheric and with remote lesions (pulvinar, cerebellum); 66.7% had cortico-pial contrast enhancement and 93.7% restriction on diffusion-weighted imaging, with cortical cytotoxic edema on apparent-diffusion coefficient, only tumor-like TPMA (n=5) presenting noticeable subcortical vasogenic edema. The heterogeneity of clinical, EEG and MRI findings contributed to a 38.6% strict focal topographic concordance between them, with the more widespread findings also attributable to the time lag between studies, seizure dynamics/etiologies and cerebral reserve. At follow-up (mean duration 29.6 months, 3-120), the brain damage induced by TPMA was responsible for a high incidence of clinical and MRI sequelae (63.2%), only tumor-like/small TPMA induced by acute symptomatic seizures presenting good clinical outcomes. Our findings may contribute to a better definition and comprehension of the TPMA electroclinical-imagiological spectrum, pathophysiology and long-term outcome.

Functional brain mapping of ictal activity in gelastic epilepsy associated with hypothalamic hamartoma: a case report.

Hypothalamic hamartomas (HHs) have been demonstrated as the cause of gelastic epilepsy, both by intracranial electrodes and functional imaging. The neocortex becomes secondarily involved, through poorly characterized propagation pathways. The detailed dynamics of seizure spread have not yet been demonstrated, owing to the limited spatial-temporal resolution of available functional mapping. We studied a patient with epilepsy associated with HH and gelastic epilepsy. Simultaneous electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) of several seizure events were obtained, with blood oxygen level dependent (BOLD) activation of the hamartoma, and left hemisphere hypothalamus, hippocampus, parietal-occipital area, cingulate gyrus, and dorsal-lateral frontal area. Integration of regional BOLD kinetics and EEG power dynamics strongly suggests propagation of the epileptic activity from the HH through the left fornix to the temporal lobe, and later through the cingulate fasciculus to the left frontal lobe. The EEG/fMRI method has the spatial-temporal resolution to study the dynamics of seizure activity, with detailed demonstration of origin and propagation pathways.

Cognitive function correlates with frontal white matter apparent diffusion coefficients in patients with leukoaraiosis.

BACKGROUND AND AIMS: Diffusion weighted imaging (DWI) displays a high sensitivity to white matter changes, even in areas where no lesions are visible. Correlation with vascular risk factors and cognitive dysfunction seems to be feasible using this technique. We aimed to test relations between age, blood pressure and cognitive function,with lesion load and average Apparent Diffusion Coefficient (ADC) values in lesioned (LWM) and in normal appearing white matter (NAWM), in patients with age related white matter lesions (ARWML). METHODS: Subjects were 29 patients (mean age 72.6 +/- 5.2 years) with different severity of ARWML on MRI and no (or mild) disability assessed by the Instrumental Activities of Daily Living Scale. Imaging lesion load was quantified in bilateral frontal, temporal, parieto-occipital, basal ganglia and infratentorial regions, using a simple visual rating scale; ADC was measured bilaterally in Regions of Interest in parieto-occipital and frontal NAWM, and in frontal periventricular LWM. Neuropsychological examination consisted of Raven Colored Progressive Matrices, Rey's Complex Figure, Digit Canceling. Symbol digit Substitution, Inverse Digit Repetition and Verbal Fluency tests. RESULTS: Visual scales scores and ADC were significantly higher in frontal and parieto-occipital regions. Both were significantly correlated to age and blood pressure, in frontal (visual scale scores and ADC) and parieto-occipital regions (ADC). Attention skills were negatively correlated to ADC in LWM and NAWM in frontal regions and with frontal region visual scale scores. CONCLUSION: Our findings suggest that severity of white matter ischemic changes is correlated with worse cognitive function, as well as advanced age and higher blood pressure.A higher vulnerability of frontal white matter to vascular disease seems to play an important role in executive dysfunction, mainly determined by impairment of attentional skills.DWI results suggest this could be true even for NAWM.

Brain mapping of epileptic activity in a case of idiopathic occipital lobe epilepsy (Panayiotopoulos syndrome).

The Panayiotopoulos type of occipital lobe epilepsy has generated great interest, but the particular brain areas involved in the peculiar seizure manifestations have not been established. We studied a patient with the syndrome, using high-resolution EEG and simultaneous EEG and functional magnetic resonance imaging (fMRI). Resolution of the scalp EEG was improved using a realistic spline Laplacian algorithm, and produced a complex distribution of current sinks and sources over the occipital lobe. The spike-related blood oxygen level dependent (BOLD) effect was multifocal, with clusters in lateral and inferior occipital lobe and lateral and anterior temporal lobe. We also performed regional dipole seeding in BOLD clusters to determine their relative contribution to generation of scalp spikes. The integrated model of the neurophysiologic and vascular data strongly suggests that the epileptic activity originates in the lateral occipital area, spreading to the occipital pole and lateral temporal lobe.

The BOLD effect of interictal spike activity in childhood occipital lobe epilepsy.

PURPOSE: Occipital lobe epilepsy (OLE) presents in childhood with different manifestations, age of onset and EEG features that form distinct syndromes. The ictal clinical symptoms are difficult to correlate with onset in particular areas in the occipital lobes, and the EEG recordings have not been able to overcome this limitation. The mapping of epileptogenic cortical regions in OLE remains therefore an important goal in our understanding of these syndromes. METHODS: In this work, three patients with two types of idiopathic childhood OLE were studied with EEG source analysis and also with mapping of the BOLD effect associated with spikes in simultaneous EEG/fMRI recordings. RESULTS: Two patients with late onset OLE provided EEG source localizations in the lateral parietal cortex and in the medial occipital areas. The BOLD activations were more consistent and restricted to the medial parietal-occipital cortex in both cases. One patient with photosensitive idiopathic OLE presented with dipole sources in the medial parietal cortex, but the BOLD activations were widespread over inferior and bilateral occipital areas and also posterior temporal ones. There was little spatial overlap between the EEG and BOLD results, but the localizations suggested by the latter are more consistent with the ictal clinical manifestations of each type of epileptic syndrome. CONCLUSIONS: Overall, the BOLD effect associated with interictal spikes maps epileptogenic areas to different localizations than the ones suggested by EEG source analysis. These maps are similar in two patients with late onset idiopathic OLE, but different from a case of photosensitive idiopathic OLE.