RESUMEN
OBJECTIVE: To evaluate whether vegetative state patients maintain circadian rhythms. RESEARCH DESIGN: An observational study of five single cases. METHODS AND PROCEDURES: Five chronic vegetative state patients underwent clinical and neurological evaluations and 2-week continuous temperature measurements. MAIN OUTCOMES AND RESULTS: The two patients with traumatic brain injury showed well-formed circadian temperature rhythms and had more reflexive behaviours and relatively low cortical and sub-cortical atrophy, whereas the three patients from anoxic-hypoxic origin demonstrated no cycles or rhythmic behaviour. CONCLUSIONS: The presence of periods of wakefulness does not imply preserved sleep-wake cycling capacity, nor preserved circadian rhythms and it should not be taken as a distinguishing feature for the definition of the vegetative state.
Asunto(s)
Regulación de la Temperatura Corporal/fisiología , Lesiones Encefálicas/fisiopatología , Ritmo Circadiano/fisiología , Hipoxia Encefálica/fisiopatología , Estado Vegetativo Persistente/fisiopatología , Vigilia/fisiología , Adulto , Anciano , Lesiones Encefálicas/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
Determining conscious processing in unresponsive patients relies on subjective behavioural assessment. Using data from hand electromyography, the authors studied the occurrence of subthreshold muscle activity in response to verbal command, as an objective indicator of awareness in 10 disorders of consciousness patients. One out of eight vegetative state patients and both minimally conscious patients (n = 2) demonstrated an increased electromyography signal specifically linked to command. These findings suggest electromyography could be used to assess awareness objectively in pathologies of consciousness.
Asunto(s)
Concienciación/fisiología , Electromiografía , Actividad Motora/fisiología , Músculo Esquelético/fisiopatología , Estado Vegetativo Persistente/fisiopatología , Estado Vegetativo Persistente/psicología , Adulto , Estudios de Cohortes , Femenino , Mano , Humanos , Masculino , Persona de Mediana Edad , Estado Vegetativo Persistente/etiología , Reproducibilidad de los Resultados , Análisis y Desempeño de TareasRESUMEN
BACKGROUND AND OBJECTIVE: Methodological variability in the assessment of white matter hyperintensities (WMH) in dementia may explain inconsistent reports of its prevalence and impact on cognition. We used a method of brain MRI segmentation for quantifying both tissue and WMH volumes in Alzheimer's disease (AD) and examined the association between WMH and structural and cognitive variables. METHODS: A consecutive series of 81 patients meeting NINCDS-ADRDA criteria for probable AD was studied. Nineteen healthy volunteers of comparable age served as the control group. Patients had a complete neurological and neuropsychological evaluation, and a three dimensional MRI was obtained. Images were segmented into grey matter, white matter, and cerebrospinal fluid. WMH were edited on segmented images, and lobar assignments were based on Talairach coordinates. RESULTS: Mild and moderate to severe AD patients had significantly more WMH than controls (p<0.05). WMH preferentially involved the frontal lobes (70%), were inversely correlated with grey matter cortical volume (R(2) = 0.23, p<0.001), and were significantly associated with vascular risk factors and with a worse performance on memory tasks. CONCLUSION: Objective measurements of tissue volumes in AD demonstrated that WMH are significantly related to cortical atrophy and neuropsychological impairment.