RESUMEN
Schizophrenia has long been thought to be a disconnection syndrome and several previous studies have reported widespread abnormalities in white matter tracts in individuals with schizophrenia. Furthermore, reductions in structural connectivity may also impair communication between anatomically unconnected pairs of brain regions, potentially impacting global signal traffic in the brain. Therefore, we used different communication models to examine direct and indirect structural connections (polysynaptic) communication in large-scale brain networks in schizophrenia. Diffusion-weighted magnetic resonance imaging scans were acquired from 62 patients diagnosed with schizophrenia and 35 controls. In this study, we used five network communication models including, shortest paths, navigation, diffusion, search information and communicability to examine polysynaptic communication in large-scale brain networks in schizophrenia. We showed less efficient communication between spatially widespread brain regions particulary encompassing cortico-subcortical basal ganglia network in schizophrenia group relative to controls. Then, we also examined whether reduced communication efficiency was related to clinical symptoms in schizophrenia group. Among different measures of communication efficiency, only navigation efficiency was associated with global cognitive impairment across multiple cognitive domains including verbal learning, processing speed, executive functions and working memory, in individuals with schizophrenia. We did not find any association between communication efficiency measures and positive or negative symptoms within the schizophrenia group. Our findings are important for improving our mechanistic understanding of neurobiological process underlying cognitive symptoms in schizophrenia.
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Trastornos del Conocimiento , Disfunción Cognitiva , Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagen , Trastornos del Conocimiento/complicaciones , Trastornos del Conocimiento/patología , Disfunción Cognitiva/patología , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Cognición , Imagen por Resonancia MagnéticaRESUMEN
Negative symptoms, including avolition, anhedonia, asociality, blunted affect and alogia are associated with poor long-term outcome and functioning. However, treatment options for negative symptoms are limited and neurobiological mechanisms underlying negative symptoms in schizophrenia are still poorly understood. Diffusion-weighted magnetic resonance imaging scans were acquired from 64 patients diagnosed with schizophrenia and 35 controls. Global and regional network properties and rich club organization were investigated using graph analytical methods. We found that the schizophrenia group had higher modularity, clustering coefficient and characteristic path length, and lower rich connections compared to controls, suggesting highly connected nodes within modules but less integrated with nodes in other modules in schizophrenia. We also found a lower nodal degree in the left thalamus and left putamen in schizophrenia relative to the control group. Importantly, higher modularity was associated with greater negative symptoms but not with cognitive deficits in patients diagnosed with schizophrenia suggesting an alteration in modularity might be specific to overall negative symptoms. The nodal degree of the left thalamus was associated with both negative and cognitive symptoms. Our findings are important for improving our understanding of abnormal white-matter network topology underlying negative symptoms in schizophrenia.
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Esquizofrenia , Sustancia Blanca , Humanos , Esquizofrenia/diagnóstico por imagen , Anhedonia , Imagen de Difusión por Resonancia Magnética , Tálamo/diagnóstico por imagen , Encéfalo/diagnóstico por imagenRESUMEN
OBJECTIVE: We aimed to examine white matter microstructure and connectivity in individuals with obsessive-compulsive disorder (OCD) and their unaffected siblings, relative to healthy controls. METHODS: Diffusion-weighted magnetic resonance imaging (dMRI) scans were acquired in 30 patients with OCD, 21 unaffected siblings, and 31 controls. We examined white matter microstructure using measures of fractional anisotropy (FA), radial diffusivity (RD), and axial diffusivity (AD). Structural networks were examined using network-based statistic (NBS). RESULTS: Compared to controls, OCD patients showed significantly reduced FA and increased RD in clusters traversing the left forceps minor, inferior fronto-occipital fasciculus, anterior thalamic radiation, and cingulum. Furthermore, the OCD group displayed significantly weaker connectivity (quantified by the streamline count) compared to controls in the right hemisphere, most notably in edges connecting subcortical structures to temporo-occipital cortical regions. The sibling group showed intermediate streamline counts, FA and RD values between OCD and healthy control groups in connections found to be abnormal in patients with OCD. However, these reductions did not significantly differ compared to controls. CONCLUSION: Therefore, siblings of OCD patients display intermediate levels in dMRI measures of microstructure and connectivity, suggesting white matter abnormalities might be related to the familial predisposition for OCD.
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Trastorno Obsesivo Compulsivo , Sustancia Blanca , Anisotropía , Encéfalo/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética , Imagen de Difusión Tensora , Humanos , Trastorno Obsesivo Compulsivo/diagnóstico por imagen , Hermanos , Sustancia Blanca/diagnóstico por imagenRESUMEN
We aimed to examine the whole-brain white matter connectivity and local topology of reward system nodes in patients with alcohol use disorder (AUD) and unaffected siblings, relative to healthy comparison individuals. Diffusion-weighted magnetic resonance imaging scans were acquired from 18 patients with AUD, 15 unaffected siblings of AUD patients and 15 healthy controls. Structural networks were examined using network-based statistic and connectomic analysis. Connectomic analysis showed a significant ordered difference in normalized rich club organization (AUD < Siblings < Controls). We also found rank ordered differences (Control > Sibling > AUD) for both nodal clustering coefficient and nodal local efficiency in reward system nodes, particularly left caudate, right putamen and left hippocampus. Network-based statistic analyses showed that AUD group had significantly weaker connectivity than controls in the right hemisphere, mostly in the edges connecting putamen and hippocampus with other brain regions. Our results suggest that reward system network abnormalities, especially in subcortical structures, and impairments in rich-club organization might be related to the familial predisposition for AUD.
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Alcoholismo/fisiopatología , Endofenotipos , Recompensa , Adulto , Estudios de Casos y Controles , Imagen de Difusión Tensora , Humanos , Masculino , Vías Nerviosas/fisiología , Sustancia Blanca/metabolismoRESUMEN
Toxocariasis caused by Toxocara canis or less frequently by T.catis is a common parasitic infection worldwide. Clinical spectrum in humans can vary from asymptomatic infection to serious organ disfunction depending on the load of parasite, migration target of the larva and the inflammatory response of the host. Transverse myelitis (TM) due to toxocariasis is an uncommon illness identified mainly as case reports in literature. In this report, a case of TM who was diagnosed as neurotoxocariasis by serological findings has been presented. A 44-year-old male patient complained with backache was diagnosed as TM in a medical center in which he has admitted two years ago, and treated with pregabalin and nonsteroidal drugs for six months. Because of the progression of the lesions he readmitted to another center and treated with high dose steroid therapy for three months. After six months of follow up, improvement has been achieved, however, since his symptoms reccurred in the following year he was admitted to our hospital. Magnetic resonance imaging (MRI) examination revealed a TM in a lower segment of spinal cord. He was suffering with weakness and numbness in the left lower extremity. There was no history of rural life or contact with cats or dogs in his anamnesis. Physical examination revealed normal cranial nerve functions, sensory and motor functions. There has been no pathological reflexes, and deep tendon reflexes were also normal. Laboratory findings yielded normal hemogram and biochemical tests, negative PPD and parasitological examination of stool were negative for cysts and ova. Viral hepatitis markers, anti-HIV, toxoplasma-IgM, CMV-IgM, rubella-IgM, EBV-VCA-IgM, VDRL, Brucella tube agglutination, echinococcus antibody, autoantibody tests and neuromyelitis optica test were negative. Examination of CSF showed 20 cells/mm3 (mononuclear cells), 45 mg/dl protein and normal levels of glucose and chlorine. In both serum and CSF samples of the patient Toxocara-IgG antibodies were detected by Western blot (WB) assay. Low molecular weight bands (30-40 kDa) were detected in both of the samples by repeated WB testing. CSF revealed more intense bands suggesting local antibody production. Therefore the patient was diagnosed as neurotoxocariasis, and treated with steroid and mebendazole for six weeks. Clinical improvement was detected in the case and thoracic MRI revealed significant improvement in myelitis signs two months after treatment. In conclusion, toxocariasis should be considered in the differential diagnosis of TM although the involvement of central nervous system is rare and serological testing should be performed properly in the serum and CSF samples for the diagnosis.
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Anticuerpos Antihelmínticos/líquido cefalorraquídeo , Mielitis Transversa/diagnóstico , Toxocara canis/inmunología , Toxocariasis/diagnóstico , Adulto , Animales , Anticuerpos Antihelmínticos/sangre , Western Blotting , Diagnóstico Diferencial , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina G/líquido cefalorraquídeo , Imagen por Resonancia Magnética , Masculino , Mielitis Transversa/complicaciones , Mielitis Transversa/parasitología , Toxocariasis/complicaciones , Toxocariasis/parasitologíaRESUMEN
Our primary aim with this study was to build a patient-level classifier for stroke territory in DWI using AI to facilitate fast triage of stroke to a dedicated stroke center. A retrospective collection of DWI images of 271 and 122 consecutive acute ischemic stroke patients from two centers was carried out. Pretrained MobileNetV2 and EfficientNetB0 architectures were used to classify territorial subtypes as middle cerebral artery, posterior circulation, or watershed infarcts along with normal slices. Various input combinations using edge maps, thresholding, and hard attention versions were explored. The effect of augmenting the three-channel inputs of pre-trained models on classification performance was analyzed. ROC analyses and confusion matrix-derived performance metrics of the models were reported. Of the 271 patients included in this study, 151 (55.7%) were male and 120 (44.3%) were female. One hundred twenty-nine patients had MCA (47.6%), 65 patients had posterior circulation (24%), and 77 patients had watershed (28.0%) infarcts for center 1. Of the 122 patients from center 2, 78 (64%) were male and 44 (34%) were female. Fifty-two patients (43%) had MCA, 51 patients had posterior circulation (42%), and 19 (15%) patients had watershed infarcts. The Mobile-Crop model had the best performance with 0.95 accuracy and a 0.91 mean f1 score for slice-wise classification and 0.88 accuracy on external test sets, along with a 0.92 mean AUC. In conclusion, modified pre-trained models may be augmented with the transformation of images to provide a more accurate classification of affected territory by stroke in DWI.
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PURPOSE: To build a stroke territory classifier model in DWI by designing the problem as a multiclass segmentation task by defining each stroke territory as distinct segmentation targets and leveraging the guidance of voxel wise dense predictions. MATERIALS AND METHODS: Retrospective analysis of DWI images of 218 consecutive acute anterior or posterior ischemic stroke patients examined between January 2017 to April 2020 in a single center was carried out. Each stroke area was defined as distinct segmentation target with different class labels. U-Net based network was trained followed by majority voting of the voxel wise predictions of the model to transform them into patient level stroke territory classes. Effects of bias field correction and registration to a common space were explored. RESULTS: Of the 218 patients included in this study, 141 (65%) were anterior stroke, and 77 were posterior stroke (35%) whereas 117 (53%) were male and 101 (47%) were female. The model built with original images reached 0.77 accuracy, while the model built with N4 bias corrected images reached 0.80 and the model built with images which were N4 bias corrected and then registered into a common space reached 0.83 accuracy values. CONCLUSION: Voxel wise dense prediction coupled with bias field correction to eliminate artificial signal increase and registration to a common space help models for better performance than using original images. Knowing the properties of target domain while designing deep learning models is important for the overall success of these models.
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Aprendizaje Profundo , Imagen de Difusión por Resonancia Magnética , Accidente Cerebrovascular , Humanos , Femenino , Masculino , Estudios Retrospectivos , Imagen de Difusión por Resonancia Magnética/métodos , Anciano , Accidente Cerebrovascular/diagnóstico por imagen , Persona de Mediana Edad , Aumento de la Imagen/métodos , Anciano de 80 o más Años , Interpretación de Imagen Asistida por Computador/métodos , Valor Predictivo de las Pruebas , Accidente Cerebrovascular Isquémico/diagnóstico por imagenRESUMEN
Magnetic resonance imaging (MRI) of the internal acoustic canal is the standard diagnostic tool for a wide range of indications in patients. This study aims to investigate the vascular variations and compression of the cranial nerves (CNs) VII and VIII at the cerebellopontine angle in patients with neuro-otologic symptoms using 3D-fast imaging employing steady-state acquisition (FIESTA) MR imaging. One hundred and eighty-seven patients (374 temporal bones) were examined on a 1.5-T MRI. In addition to conventional MR sequences, a 3D-FIESTA MR imaging was acquired. Magnetic resonance images thus obtained were evaluated with special regard to the presence of vascular contact to the CNs VII and VIII, as well as the presence of the vascular variations of the anterior inferior cerebellar artery (AICA) causing the compression of CNs. The Chi-squared test was used for statistical analysis. No statistically significant differences were found between the presence and absence of the AICA loop and/or vascular contact for the clinical symptoms of patients (P > 0.05). The cisternal and canalicular segments of CNs VII and VIII and adjacent vascular variations are well identified using 3D-FIESTA, especially by determining the relationship of the AICA variations between CNs.
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Conducto Auditivo Externo/patología , Imagen por Resonancia Magnética , Nervio Facial/patología , Enfermedades del Nervio Facial/diagnóstico , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Síndromes de Compresión Nerviosa/diagnóstico , Hueso Temporal/patología , Nervio Vestibulococlear/patología , Enfermedades del Nervio Vestibulococlear/diagnósticoRESUMEN
PURPOSE: To determine whether radiation exposure increased among different ages with chest computed tomography (CT) use during the coronavirus disease-2019 (COVID-19) pandemic. METHODS: Patients with chest CT scans in an 8-month period of the pandemic between March 15, 2020, and November 15, 2020, and the same period of the preceding year were included in the study. Indications of chest CT scans were obtained from the clinical notes and categorized as infectious diseases, neoplastic disorders, trauma, and other diseases. Chest CT scans for infectious diseases during the pandemic were compared with those with the same indications in 2019. The dose-length product values were obtained from the protocol screen individually. RESULTS: The total number of chest CT scans with an indication of infectious disease was 21746 in 2020 and 4318 in 2019. Total radiation exposure increased by 573% with the use of chest CT for infectious indications but decreased by 19% for neoplasia, 12% for trauma, and 43% for other reasons. The mean age of the patients scanned in 2019 was significantly higher than those scanned during the pandemic (64.6 vs. 50.3 years). A striking increase was seen in the 10-59 age group during the pandemic (P < 0.001). The highest increase was seen in the 20-29 age group, being 18.6 fold. One death was recorded per 58 chest CT scans during the pandemic. Chest CT use was substantially higher at the beginning of the pandemic. CONCLUSION: Chest CT was excessively used during the COVID-19 pandemic. Young and middle-aged people were exposed more than others. The impact of COVID-19-pandemic-related radiation exposure on public health should be followed carefully in future years.
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COVID-19 , Enfermedades Transmisibles , Exposición a la Radiación , Persona de Mediana Edad , Humanos , Pandemias , Radiografía Torácica/métodos , Tomografía Computarizada por Rayos X/efectos adversos , Tomografía Computarizada por Rayos X/métodos , Dosis de Radiación , Estudios RetrospectivosRESUMEN
Theory of mind skills are disrupted in schizophrenia. However, various theory of mind tasks measure different neurocognitive domains. This multimodal neuroimaging study aimed to investigate the neuroanatomical correlates of mental state decoding and reasoning components of theory of mind in schizophrenia and healthy controls (HCs) using T1-weighted and diffusion-weighted (DTI) magnetic resonance imaging (MRI). Sixty-two patients with schizophrenia and 34 HCs were included. The Reading the Mind in the Eyes (RMET) and Hinting tests were used to evaluate mental state decoding and reasoning, respectively. Correlations between social cognition and cortical parameters (thickness, volume, surface area), or DTI scalars (fractional anisotropy, axial diffusivity, radial diffusivity) were cluster-based corrected for multiple comparisons. In schizophrenia, RMET scores showed positive correlations in 3 clusters, including left insula thickness, right superior-temporal thickness, left superior-temporal-sulcus volume, and DTI analysis revealed that fractional anisotropy showed positive correlations in 3 clusters, including right inferior-fronto-occipital fasciculus, left forceps-major, left inferior-fronto-occipital fasciculus. In schizophrenia, Hinting test scores showed positive correlations in 3 clusters in T1-weighted MRI, including left superior-temporal-sulcus volume, left superior-temporal-sulcus surface area, left pars-orbitalis volume. In conclusion, this study provided evidence for the involvement of particular cortical regions and white matter tracts in mental state decoding and reasoning.
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Esquizofrenia , Sustancia Blanca , Humanos , Esquizofrenia/diagnóstico por imagen , Esquizofrenia/patología , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Imagen de Difusión Tensora/métodos , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Imagen por Resonancia Magnética/métodosRESUMEN
Little is known about the underlying neurobiological mechanisms in patients with obsessive-compulsive disorder (OCD). We aimed to examine cortical thickness and surface area in individuals with OCD and their unaffected siblings, comparing them to healthy controls. 30 patients with OCD, 21 unaffected siblings (SIB) and 30 controls underwent structural magnetic resonance imaging. Structural images were analyzed using the FreeSurfer software package (version 6.0). Compared to healthy controls, both OCD and SIB groups showed significantly lower cortical thickness in the right anterior insula. Surface areas of the superior frontal gyrus, paracentral gyrus and precuneus of the right hemisphere were also reduced in OCD patients compared to controls. There were no significant differences in cortical thickness and surface area between the OCD and SIB groups. We did not detect any significant differences in subcortical volumes between groups. Lower cortical thickness in the right anterior insula in both OCD patients and unaffected siblings may represent a potential structural endophenotype for OCD.
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Imagen por Resonancia Magnética , Trastorno Obsesivo Compulsivo , Humanos , Imagen por Resonancia Magnética/métodos , Hermanos , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/patología , Trastorno Obsesivo Compulsivo/diagnóstico por imagen , Trastorno Obsesivo Compulsivo/patología , Lóbulo Parietal/patologíaRESUMEN
Anatomic variations of the anterior cruciate ligament (ACL) are very rare. The prevalence of congenital aplasia or hypoplasia of the ACL is 0.017 per 1,000 live births. The normal ACL consists of the anteromedial (AMB) and posterolateral bundles (PLB). Together, they attach to a fossa on the posteromedial aspect of the lateral femoral condyle. The PLB fibrils are smaller and shorter than those of the AMB. We report an ACL variation that had not been previously described, in which the PLB was attached to an intraarticular accessory ossicle, without causing knee instability. The large accessory ossicle caused pain. We reviewed the anatomy, anomalies, and variation in the ACL.
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Ligamento Cruzado Anterior/anomalías , Articulación de la Rodilla/anomalías , Adulto , Humanos , MasculinoRESUMEN
Recent theories suggest a shift from model-based goal-directed to model-free habitual decision-making in obsessive-compulsive disorder (OCD). However, it is yet unclear, whether this shift in the decision process is heritable. We investigated 32 patients with OCD, 27 unaffected siblings (SIBs) and 31 healthy controls (HCs) using the two-step task. We computed behavioral and reaction time analyses and fitted a computational model to assess the balance between model-based and model-free control. 80 subjects also underwent structural imaging. We observed a significant ordered effect for the shift towards model-free control in the direction OCD > SIB > HC in our computational parameter of interest. However less directed analyses revealed no shift towards model-free control in OCDs. Nonetheless, we found evidence for reduced model-based control in OCDs compared to HCs and SIBs via 2nd stage reaction time analyses. In this measure SIBs also showed higher levels of model-based control than HCs. Across all subjects these effects were associated with the surface area of the left medial/right dorsolateral prefrontal cortex. Moreover, correlations between bilateral putamen/right caudate volumes and these effects varied as a function of group: they were negative in SIBs and OCDs, but positive in HCs. Associations between fronto-striatal regions and model-based reaction time effects point to a potential endophenotype for OCD.
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Cuerpo Estriado/fisiopatología , Lóbulo Frontal/fisiopatología , Modelos Neurológicos , Vías Nerviosas/fisiopatología , Trastorno Obsesivo Compulsivo/fisiopatología , Adulto , Cognición/fisiología , Endofenotipos , Femenino , Humanos , Masculino , Tiempo de Reacción/fisiología , Análisis de Regresión , Hermanos , Adulto JovenRESUMEN
SUMMARY: Glioblastoma multiforme (GBM) is the most common lethal primary central nervous system tumor in adults. GBM is rarely seen in childhood and adolescence as primary intraventricular tumors. Few cases of solitary intraventricular GBM in adolescence have been reported to date. We report a 16-year-old boy with progressive disorientation, diffuse headache, vomiting, and increased intracranial pressure. Computed tomography and magnetic resonance imaging confirmed that the tumor filled posterior body and occipital horn of the left lateral ventricle and also invaded the surrounding parenchyma. Incomplete removal of the lesion was achieved and a pathologic diagnosis of GBM was carried out. We present a case with an uncommon subtype of glial tumor (GBM) in childhood located in a very rare site. The clinical course, radiologic findings, and possible treatment regimens are reviewed.
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Neoplasias del Ventrículo Cerebral/patología , Glioblastoma/patología , Ventrículos Laterales/patología , Adolescente , Antineoplásicos/uso terapéutico , Neoplasias del Ventrículo Cerebral/terapia , Quimioterapia Adyuvante , Terapia Combinada , Craneotomía , Resultado Fatal , Glioblastoma/terapia , Humanos , Imagen por Resonancia Magnética , Masculino , Recurrencia Local de Neoplasia/patología , Radioterapia Adyuvante , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND: Idiopathic intracranial hypertension (IIH) is a disease characterised by increased cerebral pressure without a mass or hydrocephalus. We aimed to differentiate migraine and IIH patients based on imaging findings. RESULTS: Patients with IIH (n = 32), migraine patients (n = 34) and control subjects (n = 33) were evaluated. Routine magnetic resonance imaging, contrast-enhanced 3D magnetic resonance venography and/or T1-weighted 3D gradient-recalled echo were taken with a 1.5 T magnetic resonance scanner. Optic-nerve sheath distention, flattened posterior globe and the height of the pituitary gland were evaluated in the three groups. Transverse sinuses (TS) were evaluated with respect to score of attenuation/stenosis and distribution. Pearson chi-square, Fisher's exact test and chi-square trend statistical analyses were used for comparisons between the groups. A p-value of <0.05 was considered statistically significant. Decreased pituitary gland height, optic-nerve sheath distention and flattened posterior globe were found to be statistically significant (p < 0.001) in IIH patients. Bilateral TS stenosis was also more common in IIH patients than in the control group and migraine group (p = 0.02). CONCLUSION: Decreased pituitary gland height, optic-nerve sheath distention, flattened posterior globe, bilateral stenosis and discontinuity in TS are significant findings in differentiating IIH cases from healthy individuals and migraine patients. Bilateral TS stenosis may be the cause rather than the result of increased intracranial pressure. The increase in intracranial pressure, which is considered to be responsible for the pathophysiology of IIH, is not involved in the pathophysiology of migraine.
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Interpretación de Imagen Asistida por Computador/métodos , Trastornos Migrañosos/diagnóstico por imagen , Neuroimagen/métodos , Seudotumor Cerebral/diagnóstico por imagen , Adolescente , Adulto , Diagnóstico Diferencial , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Trastornos Migrañosos/patología , Flebografía/métodos , Seudotumor Cerebral/patología , Estudios Retrospectivos , Adulto JovenRESUMEN
OBJECTIVE: To investigate the correlation between the electrophysiological and radiological findings of primary hemifacial spasm patients. SUBJECTS: Patients with primary hemifacial spasm who had had no botulinum toxin treatment previously were included in the study. DESIGN: In this prospective study patients underwent cerebral magnetic resonance imaging,a magnetic resonance angiography investigation and an electrophysiological examination after informed consent had be given by the patients. The facial nerve distal latency, amplitude and blink reflex responses were recorded as well as clinical and demographic data. RESULTS: Twenty five patients completed radiological and electrophysiological investigations. The radiological investigations disclosed neurovascular compromise which can cause hemifacial spasm in twelve patients (48%) while the findings of two patients were not considered as a certain cause of hemifacial spasm. All patients except two had at least one electrophysiological abnormality (92%). The most frequent finding was an increased R1/D ratio which suggested an increased central conduction time. CONCLUSION: In this study, an increased R1/D ratio suggests that there is a functional impairment in the brain stem even if it is not possible to disclose structural abnormalities in some hemifacial spasm patients. Combining magnetic stimulation may be a useful tool for further investigations. An inadequate radiological investigation might be the cause of relatively low radiological abnormalities in comparison with the electrophysiological ones.
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Encéfalo/diagnóstico por imagen , Músculos Faciales/fisiopatología , Nervio Facial/fisiopatología , Espasmo Hemifacial/fisiopatología , Adulto , Anciano , Parpadeo/fisiología , Encéfalo/irrigación sanguínea , Angiografía Cerebral/métodos , Electrofisiología/métodos , Músculos Faciales/inervación , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Angiografía por Resonancia Magnética/métodos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
Background Medication-overuse headache is a common clinical entity, but neuroimaging studies investigating volumetric and microstructural alterations of the brain in medication-overuse headache are rare. Therefore, in the current longitidunal study we evaluated gray matter volume and white matter integrity in patients with medication-overuse headache before and after drug withdrawal. Methods A prospective study evaluated 27 patients with medication-overuse headache and 27 age-, sex-, and education-matched healthy adults. High-resolution T1-weighted magnetic resonance imaging and diffusion tensor imaging were obtained from the control group and medication-overuse headache patients before and six months after drug withdrawal. Tract-based spatial statistics of multiple diffusivity indices and voxel-based morphometry were employed to investigate white and gray matter abnormalities. Results No correlation was found between age, gender, education and smoking status in both groups. The most commonly overused medications were simple analgesics (96.3%) and combined analgesics (3.7%). The mean duration of the history of medication overuse and headaches was 56.7 ± 63.5 months. White matter diffusional and gray matter morphological alterations including volume, fractional anisotropy, radial diffusivity, and axial diffusivity analyses showed no significant relationship in the patients before and six months after withdrawal of analgesics. Also no difference was observed between the patients versus controls. Conclusion Our data demonstrated no structural alterations within the brain in medication-overuse headache.
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Sustancia Gris/patología , Cefaleas Secundarias/inducido químicamente , Cefaleas Secundarias/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Neuroimagen/métodos , Síndrome de Abstinencia a Sustancias/diagnóstico por imagen , Sustancia Blanca/patología , Adulto , Estudios de Casos y Controles , Imagen de Difusión Tensora , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
OBJECTIVE: To assess the efficacy of inhibitory repetitive transcranial magnetic stimulation (rTMS) and neuromuscular electrical stimulation (NMES) on upper extremity motor function in patients with acute/subacute ischemic stroke. METHODS: Twenty-five ischemic acute/subacute stroke subjects were enrolled in this randomized controlled trial. Experimental group 1 received low frequency (LF) rTMS to the primary motor cortex of the unaffected side + physical therapy (PT) including activities to improve strength, flexibility, transfers, posture, balance, coordination, and activities of daily living, mainly focusing on upper limb movements; experimental group 2 received the same protocol combined with NMES to hand extensor muscles; and the control group received only PT. Functional magnetic resonance imaging (fMRI) scan was used to evaluate the activation or inhibition of the affected and unaffected primary motor cortex. RESULTS: No adverse effect was reported. Most of the clinical outcome scores improved significantly in all groups, however no statistically significant difference was found between groups due to the small sample sizes. The highest percent improvement scores were observed in TMS + NMES group (varying between 48 and 99.3%) and the lowest scores in control group (varying between 13.1 and 28.1%). Hand motor recovery was significant in both experimental groups while it did not change in control group. Some motor cortex excitability changes were also observed in fMRI. CONCLUSION: LF-rTMS with or without NMES seems to facilitate the motor recovery in the paretic hand of patients with acute/subacute ischemic stroke. TMS or the combination of TMS + NMES may be a promising additional therapy in upper limb motor training. Further studies with larger numbers of patients are needed to establish their effectiveness in upper limb motor rehabilitation of stroke.
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Terapia por Estimulación Eléctrica/métodos , Corteza Motora/fisiopatología , Evaluación de Resultado en la Atención de Salud , Paresia/rehabilitación , Recuperación de la Función/fisiología , Rehabilitación de Accidente Cerebrovascular/métodos , Accidente Cerebrovascular/terapia , Estimulación Magnética Transcraneal/métodos , Extremidad Superior/fisiopatología , Anciano , Isquemia Encefálica/complicaciones , Terapia por Ejercicio/métodos , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Terapia Ocupacional/métodos , Paresia/etiología , Método Simple Ciego , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/fisiopatología , Estimulación Eléctrica Transcutánea del Nervio/métodosRESUMEN
BACKGROUND: This study investigates the frequency of hyperintensities, which are common in bipolar disorder, in sufferers' siblings who are free of bipolar disorder and to ascertain whether these lesions reflect any familial characteristics. It offers an assessment of the relationship between these lesions and clinical characteristics. METHODS: The study group consisted of 12 patients with bipolar disorder, their siblings who had no history of mental disorder, and a matched control group. All three groups were assessed using SCID-I (Structured Clinical Interview for DSM-IV Axis I Disorders) for diagnosis, and MRI (magnetic resonance imaging) for signal hyperintensity. RESULTS: No periventricular white matter lesions were encountered in any groups. It was found that in the patients and siblings, the location was in the right cerebral hemisphere in the deep white matter, whereas it was in the left cerebral hemisphere for the control group. Only in the patient group were lesions detected in subcortical white matter in the right cerebral hemisphere. The lesions were localized in the fronto-parietal area. Considering the brain as a whole, more hyperintensities were detected in the patient group compared to the other two groups. The onset of the disorder with a manic episode was increasing probably in the presence of hyperintensities. CONCLUSIONS: Despite being alike in terms of age, more hyperintensities were detected in the patient group than in the siblings and control groups. Contrary to the control group, however, hyperintensities were localized in the right cerebral hemisphere in both the patients and the siblings groups. Hyperintensities seen in the left cerebral hemisphere yield a nonspecific impression. Siblings who have hyperintensities in the right cerebral hemisphere should be followed up and investigated with regard to bipolar disorder.
Asunto(s)
Trastorno Bipolar/diagnóstico por imagen , Lóbulo Frontal/diagnóstico por imagen , Imagen por Resonancia Magnética , Hermanos , Adulto , Femenino , Humanos , Masculino , RadiografíaRESUMEN
The present study was undertaken to determine the relationship between spinal radiological changes of ankylosing spondylitis (AS), spinal mobility, and physical functioning. Thirty-one patients diagnosed as AS according to the modified New York criteria for AS were included in this study. Three radiographic scoring methods were used to assess spinal damage. Severity of spinal involvement was assessed by using Stoke Ankylosing Spondylitis Spine Score (SASSS) and Bath Ankylosing Spondylitis Radiographic Index-Spine (BASRI-S). To assess the extent of spinal involvement, the total number of vertebrae showing radiological findings attributable to AS [number of vertebrae involved (NoVI)] was calculated according to the AS grading system defined by Braun et al. Statistical analysis, consisting of bivariate correlation, Spearman correlation, and multiple linear regression analysis, was performed using Windows Statistical Package for the Social Sciences 13.0. NoVI was negatively correlated with modified Schober and lateral spinal flexion and was positively correlated with occiput-to-wall distance and BASMI. SASSS was negatively correlated with the modified Schober. BASRI-S was negatively correlated with the modified Schober and positively correlated with BASMI. When BASMI and Bath Ankylosing Spondylitis Functional Index were taken as dependent variables, only the NoVI was found to be associated with BASMI. In our data, the extent of spinal involvement (NoVI) showed a more significant correlation with spinal measurements such as modified Schober and BASMI as compared with the other radiologic scores (SASSS and BASRI-S). Furthermore, because only the NoVI was found to be associated with BASMI, we can conclude that the extent of spinal involvement, which also includes thoracic vertebrae, affects spinal measurements.