RESUMEN
BACKGROUND: Very recently, cognitively normal, middle-aged adults with severe obstructive sleep apnea (OSA) were shown to have regional cortical amyloid-ß deposits. In the normal brain, amyloid tracer (e.g., [11C]-PiB) uptake is observed in white matter (WM) but not in cortical gray matter (GM), resulting in clear GM-WM contrast. There are no reports on possible changes in this contrast in severe OSA. OBJECTIVES: Evaluate changes in the global [11C]-PiB GM-WM contrast and study if factors reflecting clinical and imaging characteristics are associated with them. DESIGN AND SETTING: Cross-sectional imaging study. PARTICIPANTS: 19 cognitively intact middle-aged (mean 44 years) patients with severe OSA (Apnea-Hypopnea Index >30/h), carefully selected to exclude any other possible factors that could alter brain health. MEASUREMENTS: Detailed neuroimaging (amyloid PET, MRI). Signs of possible alterations in amyloid tracer GM-WM contrast and kinetics were studied with static and dynamic [11C]-PiB PET and WM structures with detailed 3.0T MRI. RESULTS: Static [11C]-PiB PET uptake showed significantly decreased GM-WM contrast in 5 out of 19 patients. This was already clearly seen in visual evaluation and also detected quantitatively using retention indexes. Dynamic imaging revealed decreased contrast due to alterations in trace accumulation in the late phase of [11C]-PiB kinetics. Decreased GM-WM contrast in the late phase was global in nature. MRI revealed no corresponding alterations in WM structures. Importantly, decreased GM-WM contrast was associated with smoking (p = 0.007) and higher Apnea-Hypopnea Index (p = 0.001). CONCLUSIONS: Severe OSA was associated with decreased GM-WM contrast in amyloid tracer uptake, with significant correlation with clinical parameters of smoking and AHI. The results support and further extend the current understanding of the deleterious effect of severe OSA on proper amyloid clearance, possibly reflecting dysfunction of the brain glymphatic system.
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Apnea Obstructiva del Sueño , Sustancia Blanca , Adulto , Amiloide/metabolismo , Compuestos de Anilina , Radioisótopos de Carbono , Humanos , Persona de Mediana Edad , Tomografía de Emisión de Positrones/métodos , Apnea Obstructiva del Sueño/diagnóstico por imagen , Tiazoles , Sustancia Blanca/diagnóstico por imagenRESUMEN
OBJECTIVES: To prospectively determine the feasibility of preoperative supine breast MRI in breast cancer patients scheduled for oncoplastic breast-conserving surgery. METHODS: In addition to a diagnostic prone breast MRI, a supplementary supine MRI was performed with the patient in the surgical position including skin markers. Tumours' locations were ink-marked on the skin according to findings obtained from supine MRI. Changes in tumours' largest diameter and locations between prone and supine MRI were measured and compared to histology. Nipple-to-tumour and tumour-to-chest wall distances were also measured. Tumours and suspicious areas were surgically removed according to skin ink-markings. The differences between MRI measurements with reference to histopathology were evaluated with the paired-sample t test. RESULTS: Fourteen consecutive patients, 15 breasts and 27 lesions were analysed. Compared to histology, prone MRI overestimated tumour size by 47.1% (p = 0.01) and supine MRI by 14.5% (p = 0.259). In supine MRI, lesions' mean diameters and areas were smaller compared to prone MRI (- 20.9%, p = 0.009 and - 38.3%, p = 0.016, respectively). This difference in diameter was more pronounced in non-mass lesions (- 31.2%, p = 0.031) compared to mass lesions (- 9.2%, p = 0.009). Tumours' mean distance from chest wall diminished by 69.4% (p < 0.001) and from nipple by 18.2% (p < 0.001). Free microscopic margins were achieved in first operation in all patients. CONCLUSIONS: Supine MRI in the surgical position is feasible and useful in the precise localisation of prone MRI-detected lesions and provides a helpful tool to implement in surgery. Supine MRI more accurately determines tumours' size and location and might have an important role to diminish overestimations. KEY POINTS: ⢠Breath-hold supine breast MRI is feasible using commercially available coils and sequences. ⢠Size and area of lesions on MRI were consistently smaller when measured from the supine position as compared to the prone position. ⢠Supine breast MRI is useful in the precise preoperative localisation of prone MRI-detected lesions. â¢.
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Neoplasias de la Mama/diagnóstico , Imagen por Resonancia Magnética/métodos , Mastectomía Segmentaria/métodos , Posición Supina , Adulto , Anciano , Neoplasias de la Mama/cirugía , Estudios de Factibilidad , Femenino , Humanos , Persona de Mediana Edad , Reproducibilidad de los ResultadosRESUMEN
BACKGROUND: Normal displacement of the conus medullaris with unilateral and bilateral SLR has been quantified and the "principle of linear dependence" has been described. PURPOSE: Explore whether previously recorded movements of conus medullaris with SLRs are i) primarily due to transmission of tensile forces transmitted through the neural tissues during SLR or ii) the result of reciprocal movements between vertebrae and nerves. STUDY DESIGN: Controlled radiologic study. METHODS: Ten asymptomatic volunteers were scanned with a 1.5T magnetic resonance (MR) scanner using T2 weighted spc 3D scanning sequences and a device that permits greater ranges of SLR. Displacement of the conus medullaris during the unilateral and sham SLR was quantified reliably with a randomized procedure. Conus displacement in response to unilateral and sham SLRs was quantified and the results compared. RESULTS: The conus displaced caudally in the spinal canal by 3.54±0.87 mm (mean±SD) with unilateral (p≤.001) and proximally by 0.32±1.6 mm with sham SLR (p≤.542). Pearson correlations were higher than 0.99 for both intra- and inter-observer reliability and the observed power was 1 for unilateral SLRs and 0.054 and 0.149 for left and right sham SLR respectively. CONCLUSIONS: Four relevant points emerge from the presented data: i) reciprocal movements between the spinal cord and the surrounding vertebrae are likely to occur during SLR in asymptomatic subjects, ii) conus medullaris displacement in the vertebral canal with SLR is primarily due to transmission of tensile forces through the neural tissues, iii) when tensile forces are transmitted through the neural system as in the clinical SLR, the magnitude of conus medullaris displacement prevails over the amount of bone adjustment.
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Pierna/fisiopatología , Imagen por Resonancia Magnética , Enfermedades de la Médula Espinal/fisiopatología , Médula Espinal/fisiopatología , Adulto , Femenino , Cadera/diagnóstico por imagen , Cadera/fisiopatología , Humanos , Rodilla/diagnóstico por imagen , Rodilla/fisiopatología , Pierna/diagnóstico por imagen , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/fisiopatología , Masculino , Movimiento/fisiología , Pelvis/diagnóstico por imagen , Pelvis/fisiopatología , Médula Espinal/diagnóstico por imagen , Enfermedades de la Médula Espinal/diagnóstico por imagen , Nervios Espinales/diagnóstico por imagen , Nervios Espinales/fisiopatología , Vértebras Torácicas/diagnóstico por imagen , Vértebras Torácicas/fisiopatologíaRESUMEN
The co-registration of transcranial magnetic stimulation and electroencephalography (TMS-EEG) is emerging as a successful technique for causally exploring cortical mechanisms and connections. However, various artefacts could affect TMS-EEG signals. Correct artefacted channels reconstruction is crucial to obtain accurate topographical representation and consequently accurate inverse problem solution, in order to map in a proper way the global brain responses after the stimulation of one particular brain region of interest. In this paper, we discuss the problem of artefacted channels interpolation in TMS-EEG signals. Aim of the study was to investigate two different interpolation methods evaluating their performance in two datasets: one constituted by 19 EEG channels montage (low-density spatial resolution) and the other one by 60 EEG channels montage (high-density spatial resolution). In addition, these evaluations took place in two different contexts of application: after the averaging of TMS Evoked Potentials (TEPs) in a time interval to obtain a global information in the considered range, and at fixed latencies 100 ms and 300 ms after the TMS stimulus. The results showed that the global reconstruction error was lower at fixed latencies for the high-density electrodes spatial resolution montage.
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Mapeo Encefálico , Electroencefalografía , Estimulación Magnética Transcraneal , Encéfalo , Potenciales Evocados , HumanosRESUMEN
Studies concerning the role of denture status on in temporomandibular disorders (TMD) are scarce. The aim of this study was to evaluate the association of tooth loss and denture status with clinical findings of TMD. The data were obtained from 6316 subjects aged ≥ 30 years from the Finnish Health 2000 Survey. The associations between clinically assessed TMD findings and number of teeth, wearing of removable dentures, need for denture repair and age of the dentures were analysed by means of chi-square test and logistic regression. Among women after adjusting for age, having fewer teeth or wearing complete dentures associated with restricted maximum interincisal distance and pain on palpation of the temporomandibular joints (TMJ) and masticatory muscles. After adding education level and depression in the model, the associations between TMJ pain and explanatory variables were weakened. Among men, having a higher number of teeth associated with occurence of TMJ crepitation. Subjective need for repair of dentures and having a denture aged ≥ 5 years associated with pain on palpation in masticatory muscles among women. Among men, both the objective and subjective need for denture repair and having at least one denture aged ≥ 5 years or been repaired during the past 5 years associated negatively with the presence of TMJ crepitation. It can be concluded that edentulousness, wearing of complete dentures and poor condition of dentures associate with pain-related TMD findings among women. Psychosocial factors have a modifying effect on these associations.
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Dentaduras/estadística & datos numéricos , Síndrome de la Disfunción de Articulación Temporomandibular/epidemiología , Pérdida de Diente/epidemiología , Adulto , Anciano , Dolor Facial/epidemiología , Femenino , Humanos , Masculino , Músculos Masticadores/fisiopatología , Persona de Mediana Edad , Factores de Riesgo , Factores Sexuales , Factores de TiempoRESUMEN
BACKGROUND AND PURPOSE: EPM1, caused by mutations in the CSTB gene, is the most common form of PME. The most incapacitating symptom of EPM1 is action-activated and stimulus-sensitive myoclonus. The clinical severity of the disease varies considerably among patients, but so far, no correlations have been observed between quantitative structural changes in the brain and clinical parameters such as duration of the disease, age at onset, or myoclonus severity. The aim of this study was to evaluate possible changes in CTH of patients with EPM1 compared with healthy controls and to correlate those changes with clinical parameters. MATERIALS AND METHODS: Fifty-three genetically verified patients with EPM1 and 70 healthy volunteers matched for age and sex underwent 1.5T MR imaging. T1-weighted 3D images were analyzed with CTH analysis to detect alterations. The patients were clinically evaluated for myoclonus severity by using the UMRS. Higher UMRS scores indicate more severe myoclonus. RESULTS: CTH analysis revealed significant thinning of the sensorimotor and visual and auditory cortices of patients with EPM1 compared with healthy controls. CTH was reduced with increasing age in both groups, but in patients, the changes were confined specifically to the aforementioned areas, while in controls, the changes were more diffuse. Duration of the disease and the severity of myoclonus correlated negatively with CTH. CONCLUSIONS: Cortical thinning in the sensorimotor areas in EPM1 correlated significantly with the degree of the severity of the myoclonus and is most likely related to the widespread stimulus sensitivity in EPM1.
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Corteza Cerebral/patología , Imagen por Resonancia Magnética/métodos , Síndrome de Unverricht-Lundborg/patología , Adolescente , Adulto , Atrofia/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto JovenRESUMEN
BACKGROUND: The clinical benefits of intensive stroke rehabilitation vary individually. We used multimodal functional imaging to assess the relationship of clinical gain and imaging changes in patients with chronic stroke whose voluntary motor control improved after constraint-induced movement therapy (CIMT). METHODS: Eleven patients (37.6 ± 36.8 months from stroke) were studied by functional MRI (fMRI), transcranial magnetic stimulation (TMS), and behavioral assessment of hand motor control (Wolf Motor Function Test) before and after 2 weeks of CIMT. Individual and group-level changes in imaging and behavioral parameters were investigated. RESULTS: Increase in fMRI activation in the sensorimotor areas was greater amongst those subjects who had poor hand motor behavior before therapy and/or whose motor behavior improved notably because of therapy than amongst subjects with relatively good motor behavior already before therapy. The magnitude of CIMT-induced changes in task-related fMRI activation differed between lesioned and non-lesioned hemispheres, and the fMRI laterality index was different for paretic and non-paretic hand tasks. The corticospinal conduction time in TMS was significantly decreased after CIM therapy. CONCLUSIONS: Alterations in sensorimotor cortical activations (fMRI) and corticospinal conductivity (TMS) were observed after intensive rehabilitation in patients with chronic stroke. Activation and functional changes in fMRI and TMS correlated significantly with the degree of clinical improvement in hand motor behavior. The present data advance the understanding of the functional underpinnings of motor recovery, which may be obtained even years after the stroke.
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Imagen por Resonancia Magnética , Corteza Motora/irrigación sanguínea , Modalidades de Fisioterapia , Recuperación de la Función/fisiología , Corteza Somatosensorial/irrigación sanguínea , Accidente Cerebrovascular , Adulto , Mapeo Encefálico , Enfermedad Crónica , Potenciales Evocados Motores/fisiología , Femenino , Estudios de Seguimiento , Lateralidad Funcional , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Oxígeno/sangre , Estadística como Asunto , Accidente Cerebrovascular/patología , Accidente Cerebrovascular/fisiopatología , Rehabilitación de Accidente Cerebrovascular , Estimulación Magnética TranscranealRESUMEN
OBJECTIVES: To investigate the association of smoking with bruxism while controlling for genetic and environmental factors using a co-twin-control design. Especially, the role of nicotine dependence was studied in this context. METHODS: The material derives from the Finnish Twin Cohort consisting of 12,502 twin individuals who responded to a questionnaire in 1990 (response rate of 77%). All were born in 1930-1957, the mean age being 44 years. The questionnaire covered 103 multiple choice questions, 7 dealing with tobacco use and 22 with sleep and vigilance matters, including perceived bruxism. In addition, a subsample derived from the Nicotine Addiction Genetics Finland Study containing 445 twin individuals was studied. RESULTS: In age- and gender-controlled multinomial logistic regression, both monthly and rarely reported bruxism associated with both current cigarette smoking (odds ratio [OR] = 1.74 and 1.64) and former cigarette smoking (OR = 1.64 and 1.47). Weekly bruxism associated with current smoking (OR = 2.85). Current smokers smoking 20 or more cigarettes a day reported weekly bruxism more likely (OR = 1.61-1.97) than those smoking less. Among twin pairs (N = 142) in which one twin was a weekly bruxer and the cotwin a never bruxer, there were 13 monozygotic pairs in which one twin was a current smoker and the other twin was not. In all cases, the bruxer was the smoker (p = .0003). Nicotine dependence associated significantly with bruxism. CONCLUSIONS: Our twin study provides novel evidence for a possible causal link between tobacco use and bruxism among middle-aged adults. Nicotine dependence may be a significant predisposing factor for bruxism.
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Bruxismo/epidemiología , Fumar/epidemiología , Tabaquismo/epidemiología , Gemelos , Anciano , Causalidad , Estudios de Cohortes , Comorbilidad , Enfermedades en Gemelos/epidemiología , Femenino , Finlandia/epidemiología , Humanos , Modelos Logísticos , Masculino , Persona de Mediana EdadRESUMEN
How bruxism develops from adolescence to early adulthood remains unclear. A previous database was revisited to evaluate the natural course of self-reported tooth grinding and clenching among young Finns aged 14-23 using four assessments. Overall, the self-reported frequencies of both grinding and clenching increased during the examination period: from 13.7% to 21.7% and from 9.2% to 14.8%, respectively. There were significant increases (without a statistically significant difference between genders) in both grinding (P = 0.002) and clenching (P = 0.015) between 15 and 23 years. A significant rise in grinding between 18 and 23 years was also found (P = 0.011). It is concluded that self-reported bruxism increases from adolescence to young adulthood. Moreover, there are large differences between individuals, and fluctuations may occur in the natural course of bruxism.
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Bruxismo/psicología , Conocimientos, Actitudes y Práctica en Salud , Adolescente , Factores de Edad , Concienciación , Bruxismo/fisiopatología , Femenino , Finlandia , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Masculino , Autoimagen , Factores Sexuales , Bruxismo del Sueño/fisiopatología , Bruxismo del Sueño/psicología , Adulto JovenRESUMEN
BACKGROUND AND PURPOSE: Ventricular dilation and sulcal enlargement are common sequelae after aSAH. Our aim was to quantify the late ventricular dilation and volumes of the CSF spaces after aSAH and to determine if they correlate with neurologic and cognitive impairments frequently detected in these patients. MATERIALS AND METHODS: 3D T1-weighted images needed for volumetry were available in 76 patients 1 year after aSAH, along with 75 neuropsychological assessments. Volumes of CSF segments and ICV were quantified by SPM in 76 patients and 30 control subjects to determine CSF/ICV ratios. The mCMI was calculated to roughly evaluate the ventricular dilation. The contributing factors for enlarged ventricles and CSF volumes were reviewed from radiologic, clinical, and neuropsychological perspectives. RESULTS: The mCMI was higher in patients with aSAH (0.23 +/- 0.06) compared with control subjects (0.20 +/- 0.04; P = .020). In line with these planimetric measurements, the SPM-based CSF/ICV ratios were higher in patients with aSAH (35.58 +/- 7.0) than in control subjects (30.36 +/- 6.25; P = .001). Preoperative hydrocephalus, higher HH and Fisher grades, and focal parenchymal lesions on brain MR imaging, but not the treatment technique, were associated with ventricular enlargement. The clinical outcome and presence of neuropsychological deficits correlated significantly with CSF enlargement. CONCLUSIONS: Ventricular and sulcal enlargement, together with reduced GM volumes, after aSAH may indicate general atrophy rather than hydrocephalus. Enlarged CSF spaces correlate with cognitive deficits after aSAH. A simple measure, mCMI proved to be a feasible tool to assess the diffuse atrophic brain damage after aSAH.
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Ventrículos Cerebrales/patología , Líquido Cefalorraquídeo , Trastornos del Conocimiento/patología , Imagen por Resonancia Magnética , Hemorragia Subaracnoidea/patología , Adolescente , Adulto , Anciano , Atrofia , Derivaciones del Líquido Cefalorraquídeo , Femenino , Humanos , Hidrocefalia/patología , Hidrocefalia/cirugía , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Valor Predictivo de las Pruebas , Hemorragia Subaracnoidea/cirugía , Resultado del Tratamiento , Adulto JovenRESUMEN
OBJECTIVES: To evaluate apparent diffusion coefficient (ADC) in cerebellar subregions in patients with stroke. MATERIALS AND METHODS: The total counts and ADCs were bilaterally measured on cerebellar white matter, gray matters of medial (G1), intermediate (G2), and lateral zones (G3) on SPECT and ADC maps from 20 patients with supratentorial ischemic stroke within the first 48 h and on day 8 after onset. ADCs were also obtained from 15 age-matched controls. RESULTS: Within 48 h, the ADCs were significantly increased bilaterally in the G3, and tended to be increased bilaterally in the white matter and G1, and contralateral G2 compared with controls. On day 8, the ADCs were significantly increased in all contralateral cerebellar subregions and in ipsilateral G1 and G2, and tended to be increased in ipsilateral G3. The ADC value was significantly higher in contralateral than in ipsilateral white matter on day 8. The interhemispheric asymmetry indices (AIs) of ADC and SPECT were significantly associated with each other in G2 and G3 within 48 h, but not on day 8. The AIs of ADC and SPECT were significantly related to each other in the G3 within 48 h and on day 8. CONCLUSIONS: Supratentorial ischemic stroke may cause mild cerebellar vasogenic edema.
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Cerebelo/metabolismo , Imagen de Difusión por Resonancia Magnética , Accidente Cerebrovascular/patología , Anciano , Isquemia Encefálica/complicaciones , Mapeo Encefálico , Estudios de Casos y Controles , Cerebelo/diagnóstico por imagen , Cerebelo/patología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Fibras Nerviosas Mielínicas/diagnóstico por imagen , Fibras Nerviosas Mielínicas/patología , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/etiología , Tomografía Computarizada de Emisión de Fotón Único/métodosRESUMEN
OBJECTIVE: To evaluate possible changes in the gray matter volume of patients with Unverricht-Lundborg disease (EPM1) compared with healthy controls. METHODS: Thirty-four genetically verified patients with EPM1 and 30 healthy controls matched for age and sex underwent MRI (T1-, T2-, fluid-attenuated inversion recovery-, and T1-weighted 3-dimensional images). T1-weighted 3-dimensional images were analyzed with voxel-based morphometry (VBM) to compare the regional differences in gray matter volumes between patients and controls. The patients with EPM1 were also clinically evaluated for myoclonus severity using the Unified Myoclonus Rating Scale. RESULTS: VBM analysis revealed atrophy in the bilateral primary, premotor, and supplementary motor cortex. The thalamus and precuneus were also bilaterally affected. No infratentorial changes were detected in the group analysis. CONCLUSION: The cortical motor areas of the brain are particularly affected in EPM1, correlating with the motor symptoms of this disease. The combination of detailed imaging with neurophysiologic evaluation may help to reveal the pathogenesis of Unverricht-Lundborg disease.
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Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Corteza Motora/patología , Tálamo/patología , Síndrome de Unverricht-Lundborg/patología , Adolescente , Adulto , Atrofia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndrome de Unverricht-Lundborg/genética , Adulto JovenRESUMEN
The present study comprised 101 (48 men) employees of the Finnish Broadcasting Company with or without irregular shift work, but all with a work week of five shifts in a row followed by 2 days off. The mean age of the subjects was 41.0 years (SD = 9.9). The BiteStrip, a single-use disposable EMG device was used for one night during the work week to detect sleep bruxism. The Actiwatch Plus actigraph was worn on the non-dominant wrist for the entire week to evaluate sleep. Total sleep time and fragmentation index, the latter as a measure of sleep efficiency was calculated for the present study. The BiteStrip scores among the participants were: 0- no bruxism: 52.2% (according to the manufacturer, comparable to a sleep laboratory bruxism count of up to 39 over 5 h), 1- mild: 29.3% (40-74 counts), 2- moderate: 12.0%: (75-124 counts) and 3- severe: 6.5% (>125 counts). Severe bruxers slept less during the work week than non-bruxers (P = 0.009), but severe bruxers slept slightly more than non-bruxers during days off. The group means of the sleep fragmentation index decreased from start towards the middle of the work week and increased during days off (P = 0.016). The levels of the fragmentation indices were consistently higher in accordance with bruxism severity (P = 0.013). It was concluded that bruxism has a coherent relationship with sleep efficiency and it can be detected at home with a low cost device.
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Electromiografía/instrumentación , Músculo Masetero/fisiopatología , Bruxismo del Sueño/diagnóstico , Privación de Sueño/complicaciones , Tolerancia al Trabajo Programado/fisiología , Adulto , Análisis de Varianza , Bruxismo/diagnóstico , Bruxismo/etiología , Estudios de Casos y Controles , Electromiografía/métodos , Femenino , Servicios de Atención a Domicilio Provisto por Hospital , Humanos , Masculino , Polisomnografía , Reproducibilidad de los Resultados , Sueño/fisiología , Bruxismo del Sueño/etiología , Privación de Sueño/psicología , Encuestas y Cuestionarios , Tolerancia al Trabajo Programado/psicologíaRESUMEN
Structural studies in primates have shown that, in addition to the primary motor cortex (M1), premotor areas are a source of corticospinal tracts. The function of these putative corticospinal neuronal tracts in humans is still unclear. We found frontal non-primary motor areas (NPMAs), which react to targeted non-invasive magnetic pulses and activate peripheral muscles as fast as or even faster than those in M1. Hand muscle movements were observed in all our subjects about 20 ms after transcranial stimulation of the superior frontal gyrus (Brodmann areas 6 and 8). Stimulation of NPMA could activate both proximal and distal upper limb muscles with the same delay as a stimulation of the M1, indicating converging motor representations with direct functional connections to the hand. We suggest that these non-primary cortical motor representations provide additional capacity for the fast execution of movements. Such a capacity may play a role in motor learning and in recovery from motor deficits.
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Corteza Cerebral/fisiología , Vías Eferentes/fisiología , Lóbulo Frontal/fisiología , Mano/inervación , Mano/fisiología , Corteza Motora/fisiología , Músculo Esquelético/inervación , Músculo Esquelético/fisiología , Adulto , Mapeo Encefálico , Electromiografía , Potenciales Evocados Motores/fisiología , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Umbral Sensorial/fisiología , Corteza Somatosensorial/fisiología , Estimulación Magnética TranscranealRESUMEN
OBJECTIVE: We aimed at comparing the effects of two different electrode-to-skin contact preparation techniques on the stimulus artefact induced by transcranial magnetic stimulation (TMS) in electroencephalography (EEG) signals. METHODS: Six healthy subjects participated in a combined navigated brain stimulation (NBS) and EEG study. Electrode contacts were first prepared in the standard way of rubbing the skin using a wooden stick with a cotton tip. The location of hand motor area and the motor threshold (MT) was determined for each subject. Then, the TMS-induced artefact was measured at 60%, 80%, 100% and 120% of the MT. Subsequently, the epithelium under the electrode contacts was electrically short-circuited by puncturing with custom-made needles and the stimulation sequences were replicated. The artefact was compared between the preparation techniques. RESULTS: The TMS-induced artefact was significantly reduced after puncturing. In addition, the size and duration of the artefact depended on the applied stimulation intensity. The reduction of the artefact was largest in electrodes at and close to the stimulation site. CONCLUSIONS: Mini-puncturing technique enables more accurate analysis of TMS-induced short-latency phenomena in EEG during NBS, and it may aid in the examination of the short distance neural connectivity beneath and close to the stimulation site. SIGNIFICANCE: This study describes a practical skin preparation method that significantly improves the utility of TMS-EEG method in studying short-latency cortical connectivity.
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Artefactos , Electroencefalografía , Punciones/efectos adversos , Estimulación Magnética Transcraneal , Adulto , Encéfalo/fisiología , Mapeo Encefálico , Umbral Diferencial/fisiología , Umbral Diferencial/efectos de la radiación , Estimulación Eléctrica/métodos , Electrodos/efectos adversos , Potenciales Evocados/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Procesamiento de Señales Asistido por ComputadorRESUMEN
The main goal of this functional Magnetic Resonance Imaging (fMRI) study was to verify the hypothesis that seriously violent persons with Sz and the co-morbid diagnoses of an Antisocial Personality Disorder (APD) and a Substance Use Disorder (Sz+APD+SUD) would present a different pattern of prefrontal functioning than seriously violent persons with Sz only. In support with the main hypothesis, frontal basal cortices were significantly less activated in persons with Sz+APD+SUD during the execution of a go/no-go task than in persons with Sz only and non-violent persons without a mental illness. In contrast, significantly higher activations in frontal motor, premotor and anterior cingulate regions were observed in the Sz+APD+SUD group than in the Sz-only group.
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Trastorno de Personalidad Antisocial/epidemiología , Encéfalo/fisiopatología , Imagen por Resonancia Magnética , Esquizofrenia/epidemiología , Trastornos Relacionados con Sustancias/epidemiología , Violencia/psicología , Violencia/estadística & datos numéricos , Adulto , Trastorno de Personalidad Antisocial/diagnóstico , Trastorno de Personalidad Antisocial/psicología , Comorbilidad , Diagnóstico Dual (Psiquiatría) , Humanos , Masculino , Persona de Mediana Edad , Corteza Prefrontal/fisiopatología , Esquizofrenia/fisiopatología , Índice de Severidad de la Enfermedad , Trastornos Relacionados con Sustancias/diagnósticoRESUMEN
OBJECTIVE: To assess whether subarachnoid hemorrhage (SAH) and its treatment is followed by volume loss in temporomesial structures. METHODS: One hundred fifty-five consecutive patients with aneurysmal SAH were randomly assigned to surgical or endovascular treatment. Volumetric MRI was performed in 77 SAH patients with good or moderate clinical outcome 1 year after hemorrhage. A comprehensive neuropsychological test battery was used to evaluate the cognitive performance of the subjects. Thirty healthy individuals were imaged as MRI controls. RESULTS: The normalized hippocampal (HC) volumes were 24.7/23.7 (right/left), and the amygdaloid (AM) volumes were 21.0/20.5 in the matched control population. In SAH patients, the corresponding volumes were smaller, HC 23.2/21.3 (p = 0.072/0.002) and AM 18.4/18.7 (p = 0.012/0.045). In addition, the AM ipsilateral to the ruptured aneurysm was smaller in patients who had undergone surgical treatment (15.7) vs endovascular treatment (20.3; p < 0.001). Treatment modality did not significantly affect the measured HC volumes. The hippocampal but not amygdaloid volumes correlated with the scores of several neuropsychological tests. CONCLUSION: Subarachnoid hemorrhage and its treatment may be followed by atrophy in temporomesial structures. A clear correlation was demonstrated between neuropsychological performance and reduced temporomesial volumes.
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Imagen por Resonancia Magnética/estadística & datos numéricos , Hemorragia Subaracnoidea/patología , Hemorragia Subaracnoidea/terapia , Lóbulo Temporal/patología , Atrofia/diagnóstico , Atrofia/epidemiología , Femenino , Finlandia/epidemiología , Humanos , Imagenología Tridimensional/estadística & datos numéricos , Incidencia , Masculino , Persona de Mediana Edad , Pronóstico , Medición de Riesgo/métodos , Factores de Riesgo , Hemorragia Subaracnoidea/epidemiología , Resultado del TratamientoRESUMEN
The objective of this study was to test inter-observer variability in shade selection for porcelain restorations, using three different shade guides: Vita Lumin Vacuum, Vita 3D-Master and Procera. Nineteen young dental professionals acted as observers. The results were also compared with those of a digital colorimeter (Shade Eye Ex; Shofu, Japan). Regarding repeatability, no significant differences were found between the three shade guides, although repeatability was relatively low (33-43%). Agreement with the colorimetric results was also low (8-34%). In conclusion, shade selection shows moderate to great inter-observer variation. In teaching and standardizing the shade selection procedure, a digital colorimeter may be a useful educational tool.
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Diseño de Prótesis Dental/normas , Coloración de Prótesis/normas , Adulto , Percepción de Color , Colorimetría/normas , Restauración Dental Permanente/normas , Técnicos Dentales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Estudiantes de OdontologíaRESUMEN
Several studies support the relevance of psychological and psychosocial factors in the assessment and management of chronic musculoskeletal pain disorders, including temporomandibular pain disorders (TMDs). The aim of this study was to re-evaluate subtyping approach used in an earlier study (TI Suvinen, KR Hanes, JA Gerschman, PC Reade. J Orofac Pain 1997;11:200) and to compare perceived physical symptoms, psychological, coping and psychosocial variables between subtypes of patients who seek treatment for their temporomandibular pain and dysfunction. A total of 41 consecutive female patients were assessed multiaxially for physical symptoms, coping style and effectiveness and illness behaviour by a previously validated Temporomandibular Pain Dysfunction Questionnaire (TI Suvinen, KR Hanes, JA Gerschman, PC Reade. J Orofac Pain 1997;11:200). Additional measures of psychosocial variables included the global scores of the Beck Depression and Anxiety Inventory and Part I of the Multidimensional Pain Inventory. Subtypes were generated using an iterative partitioning method, k-means cluster analysis. Three clusters were identified and termed as Simple (22%), Intermediate (41%) and Complex (37%) temporomandibular disorders subtypes. Significant differences (P < 0.05) were found between clusters in psychological (coping style and effectiveness, disease conviction and affective disturbance) and in psychosocial variables (daily interference and social, work and family satisfaction), but not between physical variables. The results support previous studies that have shown differences in psychosocial variables in the presentation and subtyping of TMDs and the biopsychosocial orientation in assessment. The findings need to be reverified in a larger sample along specific physical diagnoses, but it is tentatively proposed how the three subtypes could be used in the classification of temporomandibular pain patients to guide management, based on the constellation of predominant psychological and psychosocial illness impact variables.
Asunto(s)
Dolor/psicología , Trastornos de la Articulación Temporomandibular/clasificación , Adaptación Psicológica , Adulto , Ansiedad , Distribución de Chi-Cuadrado , Análisis por Conglomerados , Depresión , Femenino , Humanos , Persona de Mediana Edad , Dimensión del Dolor , Calidad de Vida , Estadísticas no Paramétricas , Trastornos de la Articulación Temporomandibular/psicologíaRESUMEN
OBJECTIVE: To examine the longitudinal appearance of hippocampal (HC) damage in a prospective follow-up study of patients with newly diagnosed epilepsy. METHODS: A total of 103 patients with newly diagnosed focal epilepsy were scanned with MRI before antiepileptic medication was started. Serial MRI studies were scheduled after 1, 2 to 3, and 5 years of treatment in the ongoing follow-up study. Volumes of the HC were measured from MRI scans according to the Cavalieri method of modern design stereology and compared at different time points together with clinical variables. RESULTS: No difference was observed in the mean HC volumes between controls and patients at baseline, after 1, 2 to 3, and 5 years of follow-up. Individual analysis showed that 8% of patients had HC damage at the time of the diagnosis and 13% of patients developed HC volume decrease during 2 to 3 years of follow-up. These patients had longer duration of seizure disorder and larger seizure number before the epilepsy was diagnosed and treatment started compared with patients who did not show HC damage. CONCLUSIONS: Hippocampal volume decreases occur in individual patients with newly diagnosed focal epilepsy during the first years of treatment. The data obtained suggest that hippocampal volumetry provides a surrogate marker of the epileptic process.