RESUMEN
Tractography has become a widely available tool for the planning of neurosurgical operations as well as for neuroscientific research. The absence of patient interaction makes it easily applicable. However, it leaves uncertainty about the functional relevance of the identified bundles. We retrospectively analyzed the correlation of white matter markers with their clinical function in 24 right-handed patients who underwent first surgery for high-grade glioma. Morphological affection of the corticospinal tract (CST) and grade of paresis were assessed before surgery. Tractography was performed manually with MRTrix3 and automatically with TractSeg. Median and mean fractional anisotropy (FA) from manual tractography showed a significant correlation with CST affection (p = 0.008) and paresis (p = 0.015, p = 0.026). CST affection correlated further most with energy, and surface-volume ratio (p = 0.014) from radiomic analysis. Paresis correlated most with maximum 2D column diameter (p = 0.005), minor axis length (p = 0.006), and kurtosis (p = 0.008) from radiomic analysis. Streamline count yielded no significant correlations. In conclusion, mean or median FA can be used for the assessment of CST integrity in high-grade glioma. Also, several radiomic parameters are suited to describe tract integrity and may be used to quantitatively analyze white matter in the future.
Asunto(s)
Neoplasias Encefálicas , Imagen de Difusión Tensora , Glioma , Tractos Piramidales , Sustancia Blanca , Humanos , Tractos Piramidales/diagnóstico por imagen , Tractos Piramidales/patología , Glioma/diagnóstico por imagen , Glioma/patología , Masculino , Femenino , Persona de Mediana Edad , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Imagen de Difusión Tensora/métodos , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Estudios Retrospectivos , Adulto , Anciano , Clasificación del Tumor , Anisotropía , Paresia/diagnóstico por imagen , Paresia/patología , Paresia/etiología , Paresia/fisiopatología , RadiómicaRESUMEN
BACKGROUND: Acupuncture involving the limb region may be effective for stroke rehabilitation clinically, but the visualised and explanatory evidence is limited. Our objectives were to assess the specific effects of acupuncture for ischaemic stroke (IS) patients with hemiparesis and investigate its therapy-driven modification in functional connectivity. METHODS: IS patients were randomly assigned (2:1) to receive 10 sessions of hand-foot 12 needles acupuncture (HA, n=30) or non-acupoint (NA) acupuncture (n=16), enrolling gender-matched and age-matched healthy controls (HCs, n=34). The clinical outcomes were the improved Fugl-Meyer Assessment scores including upper and lower extremity (ΔFM, ΔFM-UE, ΔFM-LE). The neuroimaging outcome was voxel-mirrored homotopic connectivity (VMHC). Static and dynamic functional connectivity (sFC, DFC) analyses were used to study the neuroplasticity reorganisation. RESULTS: 46 ISs (mean(SD) age, 59.37 (11.36) years) and 34 HCs (mean(SD) age, 52.88 (9.69) years) were included in the per-protocol analysis of clinical and neuroimaging. In clinical, ΔFM scores were 5.00 in HA group and 2.50 in NA group, with a dual correlation between ΔFM and ΔVMHC (angular: r=0.696, p=0.000; cerebellum: r=-0.716, p=0.000) fitting the linear regression model (R2=0.828). In neuroimaging, ISs demonstrated decreased VMHC in bilateral postcentral gyrus and cerebellum (Gaussian random field, GRF corrected, voxel p<0.001, cluster p<0.05), which fitted the logistic regression model (AUC=0.8413, accuracy=0.7500). Following acupuncture, VMHC in bilateral superior frontal gyrus orbital part was increased with cerebro-cerebellar changes, involving higher sFC between ipsilesional superior frontal gyrus orbital part and the contralesional orbitofrontal cortex as well as cerebellum (GRF corrected, voxel p<0.001, cluster p<0.05). The coefficient of variation of VMHC was decreased in bilateral posterior cingulate gyrus (PPC) locally (GRF corrected, voxel p<0.001, cluster p<0.05), with integration states transforming into segregation states overall (p<0.05). There was no acupuncture-related adverse event. CONCLUSIONS: The randomised clinical and neuroimaging trial demonstrated acupuncture could promote the motor recovery and modified cerebro-cerebellar VMHC via bilateral static and dynamic reorganisations for IS patients with hemiparesis.
Asunto(s)
Terapia por Acupuntura , Cerebelo , Accidente Cerebrovascular Isquémico , Paresia , Recuperación de la Función , Humanos , Femenino , Masculino , Persona de Mediana Edad , Anciano , Accidente Cerebrovascular Isquémico/fisiopatología , Accidente Cerebrovascular Isquémico/terapia , Accidente Cerebrovascular Isquémico/diagnóstico por imagen , Accidente Cerebrovascular Isquémico/diagnóstico , Resultado del Tratamiento , Cerebelo/fisiopatología , Cerebelo/diagnóstico por imagen , Paresia/fisiopatología , Paresia/etiología , Paresia/terapia , Paresia/diagnóstico por imagen , Imagen por Resonancia Magnética , Cerebro/diagnóstico por imagen , Cerebro/fisiopatología , Plasticidad Neuronal , Adulto , Evaluación de la Discapacidad , Factores de Tiempo , Rehabilitación de Accidente Cerebrovascular , Estado FuncionalRESUMEN
Secondary morphological and mechanical property changes in the muscle-tendon unit at the ankle joint are often observed in post-stroke individuals. These changes may alter the force generation capacity and affect daily activities such as locomotion. This work aimed to estimate subject-specific muscle-tendon parameters in individuals after stroke by solving the muscle redundancy problem using direct collocation optimal control methods based on experimental electromyography (EMG) signals and measured muscle fiber length. Subject-specific muscle-tendon parameters of the gastrocnemius, soleus, and tibialis anterior were estimated in seven post-stroke individuals and seven healthy controls. We found that the maximum isometric force, tendon stiffness and optimal fiber length in the post-stroke group were considerably lower than in the control group. We also computed the root mean square error between estimated and experimental values of muscle excitation and fiber length. The musculoskeletal model with estimated subject-specific muscle tendon parameters (from the muscle redundancy solver), yielded better muscle excitation and fiber length estimations than did scaled generic parameters. Our findings also showed that the muscle redundancy solver can estimate muscle-tendon parameters that produce force behavior in better accordance with the experimentally-measured value. These muscle-tendon parameters in the post-stroke individuals were physiologically meaningful and may shed light on treatment and/or rehabilitation planning.
Asunto(s)
Electromiografía , Músculo Esquelético , Paresia , Accidente Cerebrovascular , Tendones , Ultrasonografía , Humanos , Electromiografía/métodos , Músculo Esquelético/fisiopatología , Músculo Esquelético/diagnóstico por imagen , Accidente Cerebrovascular/fisiopatología , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/complicaciones , Tendones/diagnóstico por imagen , Tendones/fisiopatología , Masculino , Persona de Mediana Edad , Paresia/fisiopatología , Paresia/diagnóstico por imagen , Paresia/etiología , Femenino , Ultrasonografía/métodos , Anciano , Procesamiento de Señales Asistido por ComputadorRESUMEN
Neurological deficits from a stroke can result in long-term motor disabilities, including those that affect walking gait. However, extensive rehabilitation following stroke is typically time limited. Establishing predictive biomarkers to identify patients who may meaningfully benefit from additional physical therapy and demonstrate improvement is important to improve the patients' quality of life. Detection of neuroplastic remodeling of the affected region and changes in the activity patterns excited while performing suitable motor tasks could have valuable implications for chronic stroke recovery. This protocol describes the use of a digitally controlled, magnetic resonance-compatible foot-induced robotic device (MR_COFID) to present a personalized foot-motor task involving trajectory following to stroke-affected subjects with gait impairment during functional magnetic resonance imaging (fMRI). In the task, foot flexion is performed against bi-directional resistive forces, which are tuned to the subject's strength in both the dorsiflexion and plantar flexion directions, while following a visual metronome. fMRI non-invasively uses endogenous deoxyhemoglobin as a contrast agent to detect blood oxygenation level-dependent (BOLD) changes between the active and resting periods during testing. Repeated periodic testing can detect therapy-related changes in excitation patterns during task performance. The use of this technique provides data to identify and measure biomarkers that may indicate the likelihood of an individual benefitting from rehabilitation beyond that which is currently provided to stroke patients.
Asunto(s)
Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Calidad de Vida , Imagen por Resonancia Magnética/métodos , Paresia/diagnóstico por imagen , Paresia/etiologíaRESUMEN
BACKGROUND: Kernohan-Woltman notch phenomenon (KWNP) classically occurs when a lesion causes compression of the contralateral cerebral peduncle against the tentorium, resulting in ipsilateral hemiparesis. It has been studied clinically, radiologically and electrophysiologically which all confirmed to cause false localizing motor signs. Here, we demonstrate the potential use of fluorine-18 fluorodeoxyglucose (18 F-FDG) positron emission tomography/computed tomography (PET/CT) to identify KWNP caused by an epidural hematoma. CASE PRESENTATION: A 29-year-old male patient post right-sided traumatic brain injury presenting with persistent ipsilateral hemiparesis. Patient underwent decompressive craniotomy and intracranial hematoma evacuation. Brain magnetic resonance imaging in the postoperative period showed a subtle lesion in the left cerebral peduncle. PET/CT was performed to exclude early brain tumor and explain his ipsilateral hemiparesis. PET/CT imaging demonstrated a focal region of intense 18 F-FDG uptake in the left cerebral peduncle. Throughout the treatment in outpatient neurorehabilitation unit, the patient exhibited a gradual recovery of his right hemiparesis. CONCLUSION: In our case report, for the first time, PET/CT offered microstructural and functional confirmation of KWNP. Moreover, our case suggests that 18 F-FDG PET/CT may serve as an important reference for the probability of functional recovery.
Asunto(s)
Fluorodesoxiglucosa F18 , Tomografía Computarizada por Tomografía de Emisión de Positrones , Masculino , Humanos , Adulto , Pronóstico , Paresia/diagnóstico por imagen , Paresia/etiología , Hematoma/complicacionesRESUMEN
In post-stroke hemiparesis, neural impairment alters muscle control, causing abnormal movement and posture in the affected limbs. A decrease in voluntary use of the paretic arm and flexed posture during rest also induce secondary tissue transformation in the upper limb muscles. To obtain a specific, accurate, and reproducible marker of the current biological status of muscles, we collected visible (VIS) and short-wave Infrared (SWIR) reflectance spectra in vivo using a portable spectroradiometer (350-2500 nm), which provided the spectral fingerprints of the elbow flexors and extensors. We compared the spectra for the affected and unaffected sides in 23 patients with post-stroke hemiparesis (25-87 years, 8 women) and eight healthy controls (33-87 years, 5 women). In eight patients, spectra were collected before and after botulinum toxin injection. Spectra underwent off-line preprocessing, principal component analysis, and partial least-squares discriminant analysis. Spectral fingerprints discriminated the muscle (biceps vs. triceps), neurological condition (normal vs. affected vs. unaffected), and effect of botulinum toxin treatment (before vs. 30 to 40 days vs. 110 to 120 days after injection). VIS-SWIR spectroscopy proved valuable for non-invasive assessment of optical properties in muscles, enabled more comprehensive evaluation of hemiparetic muscles, and provided optimal monitoring of the effectiveness of medication.
Asunto(s)
Toxinas Botulínicas/administración & dosificación , Músculo Esquelético/diagnóstico por imagen , Neurotoxinas/administración & dosificación , Paresia/diagnóstico por imagen , Accidente Cerebrovascular/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/efectos de los fármacos , Espectroscopía Infrarroja CortaRESUMEN
We report the case of a patient who experienced recurrent ipsilateral hemiparesis in the setting of predominantly-uncrossed corticospinal tracts, with concomitant neuronal reorganization of the cortical motor maps, and the presence of aberrant interhemispheric connections. Their presence was supported by our results from diffusion tensor imaging tractography, functional magnetic resonance imaging, and transcranial magnetic stimulation. To our knowledge, this has never been reported before, and provides valuable insights into the mechanisms behind post-stroke motor recovery.
Asunto(s)
Corteza Motora/diagnóstico por imagen , Paresia/diagnóstico por imagen , Tractos Piramidales/diagnóstico por imagen , Accidente Cerebrovascular/diagnóstico por imagen , Imagen de Difusión Tensora/métodos , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Persona de Mediana Edad , Corteza Motora/fisiopatología , Paresia/etiología , Paresia/fisiopatología , Tractos Piramidales/fisiopatología , Recurrencia , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/fisiopatologíaRESUMEN
It is about half a century since free-living amoebae were recognized as pathogenic organisms, but there is still much we should learn about these rare fatal human infectious agents. A recently introduced causative agent of granulomatous amoebic encephalitis, Balamuthia mandrillaris, has been reported in a limited number of countries around the world. A 3-year-old girl was referred to our tertiary hospital because of inability to establish a proper diagnosis. She had been experiencing neurologic complaints including ataxia, altered level of consciousness, dizziness, seizure, and left-sided hemiparesis. The patient's history, physical examination results, and laboratory investigations had led to a wide differential diagnosis. Computed tomography (CT) scan and magnetic resonance imaging analyses revealed multiple mass lesions. As a result, the patient underwent an intraoperative frozen section biopsy of the brain lesion. The frozen section study showed numerous cells with amoeba-like appearances in the background of mixed inflammatory cells. Medications for free-living amoebic meningoencephalitis were administered. PCR assay demonstrated B. mandrillaris as the pathogenic amoeba. Unfortunately, the patient died 14 days after her admission. To our knowledge, this is the first report of B. mandrillaris meningoencephalitis in the Middle East and the first time we have captured the organism during a frozen-section study.
Asunto(s)
Amebiasis/parasitología , Ataxia/parasitología , Balamuthia mandrillaris/patogenicidad , Infecciones Protozoarias del Sistema Nervioso Central/parasitología , Mareo/parasitología , Paresia/parasitología , Convulsiones/parasitología , Amebiasis/diagnóstico por imagen , Amebiasis/patología , Ataxia/diagnóstico por imagen , Ataxia/patología , Balamuthia mandrillaris/crecimiento & desarrollo , Biopsia , Infecciones Protozoarias del Sistema Nervioso Central/diagnóstico por imagen , Infecciones Protozoarias del Sistema Nervioso Central/patología , Preescolar , Mareo/diagnóstico por imagen , Mareo/patología , Resultado Fatal , Femenino , Humanos , Irán , Imagen por Resonancia Magnética , Paresia/diagnóstico por imagen , Paresia/patología , Convulsiones/diagnóstico por imagen , Convulsiones/patología , Tomografía Computarizada por Rayos XRESUMEN
A woman in her 60s was admitted to our hospital because of sudden-onset right hemiparesis, paresthesia, and neck pain. At first, a head CT scan was performed to rule out stroke, which did not detect any abnormalities. Subsequently, a neck CT scan was performed, which revealed a mild high-density structure compressing the dural sac within the cervical spinal canal. She was suspected to have a spinal hematoma. A MRI scan revealed a spindle-shaped structure with a heterogeneous high signal on T2-weighted and a mild high signal on T1-weighted sagittal images, which led to the diagnosis of a spontaneous spinal epidural hematoma. The patient was treated with conservative therapy upon which her symptoms improved. She was discharged seven days after admission. Spontaneous cervical spinal epidural hematoma often causes neck pain followed by unilateral spinal cord compression symptoms(such as hemiparesis and paresthesia)and can be misdiagnosed as a stroke. In cases of hemiparesis with sudden-onset neck pain, cervical lesions should be considered in the differential diagnoses in addition to stroke.
Asunto(s)
Hematoma Epidural Craneal , Hematoma Espinal Epidural , Compresión de la Médula Espinal , Femenino , Hematoma Espinal Epidural/diagnóstico , Hematoma Espinal Epidural/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Cuello , Paresia/diagnóstico por imagen , Paresia/etiologíaRESUMEN
To develop individualized motor rehabilitation, knowledge of the relationship between neuroplastic reorganization and motor recovery after pediatric arterial ischemic stroke (AIS) is crucial. Thus, we investigated functional connectivity in patients after AIS with good motor outcome and in patients with hemiparesis compared with typically developing peers. We included 18 patients (n = 9 with hemiparesis, n = 9 with good motor outcome) with pediatric AIS in the chronic phase (≥ 2 years after diagnosis, diagnosed > 16 years) and 18 peers matched by age and gender. Participants underwent a standardized motor assessment, single-pulse transcranial magnetic stimulation to determine the type of corticospinal tract wiring, and resting-state functional magnetic resonance imaging to examine motor network connectivity. Corticospinal tract wiring was contralateral in all participants. Patients with hemiparesis had lower interhemispheric connectivity strength compared with patients with good clinical outcome and peers. Patients with good clinical outcome had higher intrahemispheric connectivity strength compared with peers. Further, higher intrahemispheric connectivity was related to better motor outcome in patients. Our findings suggest that better motor outcome after pediatric AIS is related to higher motor network connectivity strength. Thus, resting-state functional connectivity might be predictive for motor recovery after pediatric AIS.
Asunto(s)
Corteza Cerebral , Accidente Cerebrovascular Isquémico , Imagen por Resonancia Magnética , Médula Espinal , Estimulación Magnética Transcraneal , Extremidad Superior/fisiopatología , Adolescente , Adulto , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/fisiopatología , Niño , Femenino , Humanos , Accidente Cerebrovascular Isquémico/diagnóstico por imagen , Accidente Cerebrovascular Isquémico/fisiopatología , Accidente Cerebrovascular Isquémico/terapia , Masculino , Paresia/diagnóstico por imagen , Paresia/fisiopatología , Médula Espinal/diagnóstico por imagen , Médula Espinal/fisiopatologíaAsunto(s)
Adrenoleucodistrofia/complicaciones , Adrenoleucodistrofia/diagnóstico por imagen , Progresión de la Enfermedad , Paresia/diagnóstico por imagen , Paresia/etiología , Miembro 1 de la Subfamilia D de Transportador de Casetes de Unión al ATP/genética , Adrenoleucodistrofia/genética , Preescolar , Humanos , Masculino , Paresia/genéticaRESUMEN
Glioblastoma multiforme might develop radiologically within a few days following unremarkable CT scan of the brain. Glioblastoma multiforme is the most frequent primary brain tumor. Initial presentations are diverse, including headache, seizures and transient or persistent neurological deficits. Cerebral imaging followed by histological examination of a tissue specimen is the mainstay of diagnosis. We report the case of a 79-year-old female patient whose computer tomography (CT) of the brain was unremarkable at first clinical presentation with a transient hemiparesis of the right side, but revealed a cerebral space-occupying lesion ultimately diagnosed as glioblastoma only 10 days later. According to our case presentation glioblastoma might develop radiologically within a few days following unremarkable CT scan of the brain. Since clinical manifestation with a transient ischemic attack (TIA)-like episode was preceding CT manifestation, this case indicates, that a magnetic resonance imaging (MRI) should be routinely performed in all patients presenting with TIA.
Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Progresión de la Enfermedad , Glioblastoma/diagnóstico por imagen , Anciano , Neoplasias Encefálicas/patología , Femenino , Glioblastoma/patología , Humanos , Ataque Isquémico Transitorio/diagnóstico por imagen , Paresia/diagnóstico por imagen , Factores de Tiempo , Tomografía Computarizada por Rayos XAsunto(s)
Lóbulo Frontal/diagnóstico por imagen , Espasticidad Muscular/diagnóstico por imagen , Paresia/diagnóstico por imagen , Polimicrogiria/diagnóstico por imagen , Atrofia/diagnóstico por imagen , Atrofia/etiología , Electromiografía/métodos , Potenciales Evocados Somatosensoriales/fisiología , Humanos , Masculino , Persona de Mediana Edad , Espasticidad Muscular/etiología , Paresia/etiología , Polimicrogiria/complicacionesAsunto(s)
Encéfalo/diagnóstico por imagen , Paresia/diagnóstico por imagen , Tractos Piramidales/diagnóstico por imagen , Accidente Cerebrovascular/diagnóstico por imagen , Adulto , Angiografía por Tomografía Computarizada , Imagen de Difusión por Resonancia Magnética , Humanos , Masculino , Paresia/etiología , Accidente Cerebrovascular/complicacionesAsunto(s)
Infarto Encefálico/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Paresia/diagnóstico por imagen , Infarto Encefálico/complicaciones , Infarto Encefálico/tratamiento farmacológico , Fibrinolíticos/uso terapéutico , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Paresia/etiología , Activador de Tejido Plasminógeno/uso terapéutico , Resultado del TratamientoRESUMEN
Hemiparesis after stroke is associated with increased neural activity not only in the lesioned but also in the contralesional hemisphere. While most studies have focused on the role of contralesional primary motor cortex (M1) activity for motor performance, data on other areas within the unaffected hemisphere are scarce, especially early after stroke. We here combined functional magnetic resonance imaging (fMRI) and transcranial magnetic stimulation (TMS) to elucidate the contribution of contralesional M1, dorsal premotor cortex (dPMC), and anterior intraparietal sulcus (aIPS) for the stroke-affected hand within the first 10 days after stroke. We used "online" TMS to interfere with neural activity at subject-specific fMRI coordinates while recording 3D movement kinematics. Interfering with aIPS activity improved tapping performance in patients, but not healthy controls, suggesting a maladaptive role of this region early poststroke. Analyzing effective connectivity parameters using a Lasso prediction model revealed that behavioral TMS effects were predicted by the coupling of the stimulated aIPS with dPMC and ipsilesional M1. In conclusion, we found a strong link between patterns of frontoparietal connectivity and TMS effects, indicating a detrimental influence of the contralesional aIPS on motor performance early after stroke.
Asunto(s)
Vías Nerviosas/fisiopatología , Paresia/fisiopatología , Desempeño Psicomotor , Recuperación de la Función , Accidente Cerebrovascular/fisiopatología , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Estudios Cruzados , Femenino , Lateralidad Funcional , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Corteza Motora/fisiopatología , Vías Nerviosas/diagnóstico por imagen , Paresia/diagnóstico por imagen , Paresia/etiología , Lóbulo Parietal/fisiopatología , Método Simple Ciego , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico por imagen , Rehabilitación de Accidente Cerebrovascular , Estimulación Magnética TranscranealRESUMEN
Stroke patients suffering from hemiparesis may show substantial recovery in the first months poststroke due to neural reorganization. While reorganization driving improvement of upper hand motor function has been frequently investigated, much less is known about the changes underlying recovery of lower limb function. We, therefore, investigated neural network dynamics giving rise to movements of both the hands and feet in 12 well-recovered left-hemispheric chronic stroke patients and 12 healthy participants using a functional magnetic resonance imaging sparse sampling design and dynamic causal modeling (DCM). We found that the level of neural activity underlying movements of the affected right hand and foot positively correlated with residual motor impairment, in both ipsilesional and contralesional premotor as well as left primary motor (M1) regions. Furthermore, M1 representations of the affected limb showed significantly stronger increase in BOLD activity compared to healthy controls and compared to the respective other limb. DCM revealed reduced endogenous connectivity of M1 of both limbs in patients compared to controls. However, when testing for the specific effect of movement on interregional connectivity, interhemispheric inhibition of the contralesional M1 during movements of the affected hand was not detected in patients whereas no differences in condition-dependent connectivity were found for foot movements compared to controls. In contrast, both groups featured positive interhemispheric M1 coupling, that is, facilitation of neural activity, mediating movements of the affected foot. These exploratory findings help to explain why functional recovery of the upper and lower limbs often develops differently after stroke, supporting limb-specific rehabilitative strategies.