Sara Gori

Alteration of Cardiac Function in Patients with Temporal Lobe Epilepsy: Different Roles of EEG-ECG Monitoring and Spectral Analysis of RR Variability

Summary: Purpose: Because several reports have described the relation between epilepsy and cardiac arrhythmias and suggest that changes in autonomic neural control of the heart could be involved in the pathogenesis of sudden unexplained death in patients with epilepsy, the aim of this study was to evaluate cardiac function in patients with temporal lobe epilepsy.

Daytime sleepiness in mild and moderate Alzheimer's disease and its relationship with cognitive impairment

The increased tendency to fall asleep during the daytime together with increased wakefulness during the night has been demonstrated in patients with advanced Alzheimers disease (AD). The aim of this study was to assess daytime sleep propensity in a cohort of patients with mild/moderate AD and to correlate it with cognitive impairment. Twenty drug‐free AD patients meeting the NINCDS‐ADRDA criteria for probable AD were evaluated. According to their Clinical Dementia Rating scores, subjects were classified into mild (CDR1; n = 11) and moderate (CDR2; n = 9) dementia patients. A group of 12 healthy subjects was taken as controls. The subjects were evaluated by the multiple sleep latency test (MSLT) after their nocturnal sleep pattern had been assessed by a polysomnographic recording throughout the night before. Both groups of AD patients showed a higher level of daytime sleepiness, which was statistically significant for mean daytime sleep latency (MDSL) (controls versus CDR1 and versus CDR2, CDR1 versus CDR2) and for 10:00 and 12:00 hour naps (controls versus CDR1, controls versus CDR2). In the entire group of AD patients, MDSL was significantly related with MMSE, De Renzis Token test, verbal fluency, verbal digit span, story recall, Ravens Progressive Matrices, Weigl test and Bentons three‐dimensional test. These data indicate that an increased sleep propensity during daytime occurs also in patients with mild/moderate AD detected by objective neurophysiological techniques.

Word recall correlates with sleep cycles in elderly subjects

Morning recall of words presented before sleep was studied in relation to intervening night sleep measures in elderly subjects. Night sleep of 30 elderly subjects aged 61–75 years was recorded. Before sleep, subjects were presented with a list of paired non‐related words and cued recall was asked immediately after the morning awakening. Recall positively correlated with average duration of NREM/REM cycles, and with the proportion of time spent in cycles (TCT) over total sleep time (TST). No significant correlations were found with other sleep or wake measures. These results suggest the importance of sleep structure for sleep‐related memory processes in elderly adults.

Evaluation of acute ischemic stroke using quantitative EEG: A comparison with conventional EEG and CT scan

The sensitivity of quantitative electroencephalogram (EEG) was compared with that of conventional EEG in patients with acute ischaemic stroke. In addition, a correlation between quantitative EEG data and computerized tomography (CT) scan findings was carried out for all the areas of lesion in order to reassess the actual role of EEG in the evaluation of stroke. Sixty-five patients were tested with conventional and quantitative EEG within 24 h from the onset of neurological symptoms, whereas CT scan was performed within 4 days from the onset of stroke. EEG was recorded from 19 electrodes placed upon the scalp according to the International 10-20 System. Spectral analysis was carried out on 30 artefact-free 4-sec epochs. For each channel absolute and relative power were calculated for the delta, theta, alpha and beta frequency bands and such data were successively represented in colour-coded maps. Ten patients with extensive lesions documented by CT scan were excluded. The results indicated that conventional EEG revealed abnormalities in 40 of 55 cases, while EEG mapping showed abnormalities in 46 of 55 cases: it showed focal abnormalities in five cases and nonfocal abnormalities in one of six cases which had appeared to be normal according to visual inspection of EEG. In a further 11 cases, where the conventional EEG revealed abnormalities in one hemisphere, the quantitative EEG and maps allowed to further localize abnormal activity in a more localized way. The sensitivity of both methods was higher for frontocentral, temporal and parieto-occipital cortical-subcortical infarctions than for basal ganglia and internal capsule lesions; however, quantitative EEG was more efficient for all areas of lesion in detecting cases that had appeared normal by visual inspection and was clearly superior in revealing focal abnormalities. When we considered the electrode related to which the maximum power of the delta frequency band is recorded, a fairly close correlation was found between the localization of the maximum delta power and the position of lesions documented by CT scan for all areas of lesion excepting those located in the striatocapsular area.

Functional magnetic resonance imaging in episodic cluster headache

We have investigated the cerebral activation centre in four patients with episodic cluster headache (CH) with functional magnetic resonance imaging (f-MRI). The patients underwent MRI scans for anatomical and functional data acquisition in the asymptomatic state, during a headache attack and after subcutaneous administration of sumatriptan. Anatomical images were acquired by means of 3D-MPRAGE sequences and f-MRI images were obtained by means of echo-planar imaging. Data was analysed using the BrainVoyager QX version 1.7.81 software package. In all patients, the data showed significant hypothalamic activation of the hypothalamus ipsilateral to the pain side, attributable to a headache attack. Overall, we have demonstrated the anatomical location of central nervous system activation by means the first f-MRI study in CH patients. f-MRI offers a good balance of spatial and temporal resolution, and this method of study appears appropriate for investigating the pathogenetic aspects of primary headaches. Positron emission tomography and f-MRI may be regarded as little or no importance in a clinical context, they do, however, offer great potential for the exploration of headache physiopathology and the effects of pharmacological treatment.

Sleep quality, chronotypes and preferential timing of attacks in migraine without aura

Clinical observations show that migraine attacks have a seasonal, menstrual and circadian timing, suggesting a role of chronobiological mechanisms and their alterations in the disease, but little experimental data exists about this issue. The aim of this study was to estimate sleep quality chronotypes and the possible circadian timing of attacks in migraneurs. One hundred patients suffering from migraine without aura according to the IHS criteria (2004), and 30 controls were enrolled. Morning and evening type subjects were more represented in migraine patients than in controls and showed a tendency towards worse sleep quality and higher disability. Forty–two percent of migraineurs presented more than 75% of their attacks at night. Morning and evening types rather than intermediate and differences between real and preferred times may represent stressors that can worsen the disease. A preferential timing for occurrence of migraine attacks during the night and early morning hours was documented.

The importance of nasal resistance in obstructive sleep apnea syndrome: a study with positional rhinomanometry.

The importance of nasal obstruction in the pathogenesis of obstructive sleep apnea syndrome (OSAS) has not yet been totally defined. Numerous studies have reported an association between nasal obstruction and OSAS, but the precise nature of this relationship remains to be clarified. This study was undertaken to evaluate the prevalence of nasal obstruction disorders in a group of OSAS patients. For this purpose, we analyzed the nasal resistance of 36 OSAS patients by performing a traditional basal anterior active rhinomanometry test (AAR) and a positional AAR, with the patient in a supine position. Seven patients had a pathologic nasal resistance in the seated position that increased further in the supine position; 9 patients had normal resistance in the seated position but a pathologic resistance in the supine position. In 20 patients, nasal resistance was normal in both positions. No statistically significant differences in the degree of apnea/hypopnea index (AHI) was found between the 20 patients with normal positional AAR and the 16 with pathologic positional AAR (p = 0.13). Moreover, no statistically significant differences in the degree of AHI was found between the 7 patients with pathologic basal and positional AAR and the 9 patients with normal basal AAR and pathologic positional AAR (p = 0.38).

Body movements during night sleep and their relationship with sleep stages are further modified in very old subjects

The night sleep of 12 healthy subjects aged 76-98 was polygraphically investigated in order to analyse body movements and their association with sleep stages at very old age; this group was compared with 11 healthy old subjects aged 61-75 years. In very old subjects sleep is less punctuated by body movements and the association of body movements with each sleep stage is further modified compared to less old subjects. Short-lasting movements emerge indifferently from stage 1, stage 2 and REM sleep, but are significantly less frequent in SWS. Furthermore, in very old subjects the probability of awakening after body movements is higher than in old subjects, suggesting that sleep is more vulnerable to the occurrence of body movements than at previous ages. The difficulty in the elderly to maintain a stable state expresses the inability to sustain and coordinate stable physiological activities characteristic of the old age. In addition, the presence of numerous awakenings, not preceded by movements, supports the hypothesis that the awakening in the very old people may be a sudden event, as should be confirmed by the study of other behavioural and physiological activities preceding awakening.

Body movements during night sleep in healthy elderly subjects and their relationships with sleep stages.

In order to enlighten the profile of body movements during sleep at old age, the night sleep of twelve elderly subjects was polygraphically investigated; seven young healthy subjects were the control group. Significantly less body movements during sleep were found in the elderly compared to young subjects, meaning that the decrease in the number of body movements observed from infancy to childhood up to adulthood also continues at later ages. Differently from young adult, whose sleep body movements mainly occur in stage REM, no specific sleep state and/or stage was preferentially associated with the occurrence of body movements in the elderly. These data may point to an age-related modification in the interaction between motor cortex control and subcortical circuits. Furthermore, when body movements occur in elderly individuals, they are significantly more often followed in the next 60 s by a sleep stage change or by a spontaneous behavioural awakening. This might reflect a peculiar inability of elderly subjects to sustain stable states, and could also suggest that body movements may act as a co-factor in a process, comprising other physiological changes, leading to state shifts.

Epilepsy after neuroimaging normalization in a woman with tacrolimus-related posterior reversible encephalopathy syndrome

Posterior reversible encephalopathy syndrome (PRES) is known to occur after solid organ transplantation, and is caused by immunosuppressive agents such as tacrolimus. PRES onset usually occurs within the first 2months after liver transplantation. Clinical findings include seizures, headache, focal neurological deficits, visual disturbances, and altered mental status. These are associated with characteristic imaging features of subcortical white matter lesions on brain MRI. Atypical localizations of this posterior leukoencephalopathy have been reported. Expeditious recognition of the syndrome may lead to a complete recovery. Abnormalities of EEG during follow-up might be associated with unfavorable seizure outcome, even when neuroimaging changes resolve. We report a case of late-onset PRES with atypical localization following liver transplantation. The patient developed epilepsy despite resolution of MRI lesions at 8 months of follow-up. EEG was a prognostic factor of seizure persistence, suggesting an incomplete recovery of brain lesions in contrast to neuroimaging findings.