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1.
Br J Neurosurg ; 37(4): 940-942, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32164445

RESUMO

We present the case of 69-year-old woman who underwent preoperative embolization of a suprasellar hemangioblastoma supplied by the artery of foramen rotundum. To our best knowledge, this is the first such report in English. We review the literature focusing on feeding arteries of sellar and suprasellar hemangioblastomas.


Assuntos
Neoplasias Cerebelares , Embolização Terapêutica , Hemangioblastoma , Feminino , Humanos , Idoso , Hemangioblastoma/diagnóstico por imagem , Hemangioblastoma/cirurgia , Neoplasias Cerebelares/cirurgia , Artérias
2.
NMR Biomed ; 35(1): e4612, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34505321

RESUMO

Spinal cord injury (SCI) can cause motor, sensory, and autonomic dysfunctions and may affect the cerebral functions. However, the mechanisms of plastic changes in the brain according to SCI severity remain poorly understood. Therefore, in the current study, we compared the brain activity of the entire neural network according to severity of SCI using fractional amplitude of low-frequency fluctuations (fALFF) analysis in resting-state functional magnetic resonance imaging (rs-fMRI). A total of 59 participants were included, consisting of 19 patients with complete SCI, 20 patients with incomplete SCI, and 20 healthy individuals. Their motor and sensory functions were evaluated. The rs-fMRI data of low-frequency fluctuations were analyzed based on fALFF. Differences in fALFF values among complete-SCI patients, incomplete-SCI patients, and healthy controls were assessed using ANOVA. Then post hoc analysis and two-sample t-tests were conducted to assess the differences between the three groups. Pearson correlation analyses were used to determine correlations between clinical measures and the z-score of the fALFF in the SCI groups. Patients with SCI (complete and incomplete) showed lower fALFF values in the superior medial frontal gyrus than the healthy controls, and were associated with poor motor and sensory function (p < .05). Higher fALFF values were observed in the putamen and thalamus, and were negatively associated with motor and sensory function (p < .05). In conclusion, alterations in the neural activity of the motor- and sensory-related networks of the brain were observed in complete-SCI and incomplete-SCI patients. Moreover, plastic changes in these brain regions were associated with motor and sensory function.


Assuntos
Encéfalo/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/fisiopatologia , Traumatismos da Medula Espinal/fisiopatologia , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Índice de Gravidade de Doença , Traumatismos da Medula Espinal/diagnóstico por imagem
3.
Exp Brain Res ; 240(9): 2389-2400, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35922524

RESUMO

Changes in the brain with age can provide useful information regarding an individual's chronological age. studies have suggested that functional connectomes identified via resting-state functional magnetic resonance imaging (fMRI) could be a powerful feature for predicting an individual's age. We applied connectome-based predictive modeling (CPM) to investigate individual chronological age predictions via resting-state fMRI using open-source datasets. The significant feature for age prediction was confirmed in 168 subjects from the Southwest University Adult Lifespan Dataset. The higher contributing nodes for age production included a positive connection from the left inferior parietal sulcus and a negative connection from the right middle temporal sulcus. On the network scale, the subcortical-cerebellum network was the dominant network for age prediction. The generalizability of CPM, which was constructed using the identified features, was verified by applying this model to independent datasets that were randomly selected from the Autism Brain Imaging Data Exchange I and the Open Access Series of Imaging Studies 3. CPM via resting-state fMRI is a potential robust predictor for determining an individual's chronological age from changes in the brain.


Assuntos
Conectoma , Adulto , Envelhecimento , Encéfalo/diagnóstico por imagem , Conectoma/métodos , Humanos , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/diagnóstico por imagem
4.
Neuroimage ; 100: 642-9, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24983712

RESUMO

Animal models of salicylate-induced tinnitus have demonstrated that salicylate modulates neuronal activity in several brain structures leading to neuronal hyperactivity in auditory and non-auditory brain areas. In addition, these animal tinnitus models indicate that tinnitus can be a perceptual consequence of altered spontaneous neural activity along the auditory pathway. Peripheral and/or central effects of salicylate can account for neuronal activity changes in salicylate-induced tinnitus. Because of this ambiguity, an in vivo imaging study would be able to address the peripheral and/or central involvement of salicylate-induced tinnitus. Therefore, in the present study, we developed a novel manganese-enhanced magnetic resonance imaging (MEMRI) method to map the in vivo functional auditory tract in a salicylate-induced tinnitus animal model by administrating manganese through the round window. We found that acute salicylate-induced tinnitus resulted in higher manganese uptake in the cochlea and in the central auditory structures. Furthermore, serial MRI scans demonstrated that the manganese signal increased in an anterograde fashion from the cochlea to the cochlear nucleus. Therefore, our in vivo MEMRI data suggest that acute salicylate-induced tinnitus is associated with higher spontaneous neural activity both in peripheral and central auditory pathways.


Assuntos
Cóclea/fisiopatologia , Nervo Coclear/fisiopatologia , Núcleo Coclear/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Zumbido/fisiopatologia , Animais , Vias Auditivas/fisiopatologia , Modelos Animais de Doenças , Aumento da Imagem , Manganês , Ratos , Ratos Sprague-Dawley
5.
J Synchrotron Radiat ; 21(Pt 1): 215-22, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24365939

RESUMO

Phase-contrast synchrotron X-ray microtomography (pcSyncX) based on the highly coherent X-ray beam has previously been used to visualize the microstructures of biologic specimens, but it has never been used to evaluate embolic debris adherent on a cerebral protection device (CPD). The purpose of this study was to demonstrate the feasibility of pcSyncX for evaluating embolic debris during carotid artery stenting (CAS). Five patients (four males, age range 67-77 years) with severe carotid artery stenosis underwent CAS. The retrieved CPD was exposed to synchrotron radiation and 1000 pcSyncX projection images were obtained by rotating the CPD through 180°. An X-ray shadow of a CPD was converted into a visual image by the scintillator. After microtomographic reconstruction, the three-dimensionally reconstructed images were further segmented into the embolic debris and CPD. The total volume of emboli was calculated by summing the volume at each scanning level. The number of membrane pores covered by emboli as seen from the outer surface was counted and the percentage of covered area was calculated. Embolic debris was clearly demonstrated not only on the inner surface and within pores but also on the outer surface of the CPD. The mean total volume of embolic debris was 0.538 × 10(-6) mm(3) (range 0.225-0.965 × 10(-6) mm(3)). Most (61.5%) of the debris was located at the apical one-third of the CPD and 20.8% of the pore area was covered by debris.


Assuntos
Estenose das Carótidas/cirurgia , Filtração/instrumentação , Embolia Intracraniana/prevenção & controle , Stents/efeitos adversos , Microtomografia por Raio-X/métodos , Idoso , Estudos de Viabilidade , Feminino , Humanos , Masculino , Estudos Prospectivos
6.
J Korean Soc Radiol ; 85(2): 381-393, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38617858

RESUMO

Purpose: Metabolic abnormalities in hepatic encephalopathy (HE) cause brain edema or demyelinating disease, resulting in symmetric regional cerebral edema (SRCE) on MRI. This study aimed to investigate the usefulness of the clustering analysis of SRCE in predicting the development of brain failure. Materials and Methods: MR findings and clinical data of 98 consecutive patients with HE were retrospectively analyzed. The correlation between the 12 regions of SRCE was calculated using the phi (Φ) coefficient, and the pattern was classified using hierarchical clustering using the φ2 distance measure and Ward's method. The classified patterns of SRCE were correlated with clinical parameters such as the model for end-stage liver disease (MELD) score and HE grade. Results: Significant associations were found between 22 pairs of regions of interest, including the red nucleus and corpus callosum (Φ = 0.81, p < 0.001), crus cerebri and red nucleus (Φ = 0.72, p < 0.001), and red nucleus and dentate nucleus (Φ = 0.66, p < 0.001). After hierarchical clustering, 24 cases were classified into Group I, 35 into Group II, and 39 into Group III. Group III had a higher MELD score (p = 0.04) and HE grade (p = 0.002) than Group I. Conclusion: Our study demonstrates that the SRCE patterns can be useful in predicting hepatic preservation and the occurrence of cerebral failure in HE.

7.
Radiology ; 266(3): 956-63, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23220892

RESUMO

PURPOSE: To investigate the usefulness of the combined categorical reporting system of ultrasonography (US) and cytology results for thyroid nodules to suggest indications of repeat US-guided fine needle aspiration cytology (FNAC). MATERIALS AND METHODS: Institutional review board approval was obtained, and the requirement for informed consent was waived for this retrospective study. From June 2001 to December 2009, 1084 patients (978 women, 106 men) who underwent repeat US-guided FNAC of thyroid nodules were included. FNAC results were reported by using the Bethesda system for reporting thyroid cytopathologic findings and five thyroid US categories (category US 1, benign; US 2, probably benign; US 3, indeterminate; US 4, probably malignant; US 5, malignant). The relative risk ratios were evaluated in each separate FNAC and combined initial category by means of Cox proportional risk model. RESULTS: Eighty-one of 1084 (7.5%) patients had malignancy over a mean follow-up time of 20.8 months (range, 3-98 months). Initial FNAC category of atypia of undetermined significance (relative risk ratio, 9.677) and US categories of US 3 (28.76), US 4 (142.0), and US 5 (411.6) had high relative risk ratios for malignancy (P < .05). Combined categories of benign cytology findings with US 3-5, nondiagnostic cytology findings with US 3-5, and atypia of undermined significance with any US categorization had high relative risk ratios of 104.80 (95% confidence interval: 53.328, 205.966). CONCLUSION: The combination of the categorical reporting systems between cytology and US results could be useful to suggest indications of repeat US-guided FNAC.


Assuntos
Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/estatística & dados numéricos , Nódulo da Glândula Tireoide/diagnóstico , Nódulo da Glândula Tireoide/epidemiologia , Ultrassonografia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Reprodutibilidade dos Testes , República da Coreia/epidemiologia , Fatores de Risco , Sensibilidade e Especificidade , Adulto Jovem
8.
Eur Radiol ; 23(10): 2880-90, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23732686

RESUMO

OBJECTIVES: This study was conducted to evaluate the effect of revascularisation, whether revascularisation improves total cerebral blood flow volume (FVTCBF), and how cerebral veins would respond to altered FVTCBF. METHODS: The 39 carotid artery stenoses in 37 patients who underwent revascularisation including 32 stentings and 7 endarterectomies were included in this prospective study. From the two-dimensional phase-contrast (2D-PC) MRI acquired before and after revascularisation, the flow volumes (FVs) of the arteries and veins were compared using paired t-test. The relationships between these parameters were correlated using Pearson's correlation coefficient. RESULTS: The mean FV in the treated carotid artery (proportion of treated artery among total FV) increased from 162.06 ml/min (25.80 %) to 267.71 ml/min (37.21 %; P < 0.001). Revascularisation increased the FVTCBF of patients from 638.66 ml/min to 716.72 ml/min (P < 0.001). The FV of the internal jugular veins, superior sagittal and straight sinuses (FVSS + SSS), and transverse sinuses increased after revascularisation (P < 0.05). Positive relationships were shown between the FVTCBF and the FVSS + SSS (r = 0.584-0.741, P < 0.001). CONCLUSIONS: Revascularisation improves the FVTCBF by increasing the FV in the treated carotid artery. The venous drainages are closely linked to FVTCBF. 2D-PC-MRI is a feasible method for evaluating comprehensively the haemodynamic improvement after revascularisation. KEY POINTS: • Revascularisation may be beneficial in ischaemic strokes due to carotid artery stenosis. • Revascularisation of the affected artery increases total cerebral blood flow volume ( FV TCBF). • Cerebral venous drainage, closely linked to FV TCBF, is also improved. • Two-dimensional phase-contrast MRI can comprehensively assess these haemodynamic improvements after carotid revascularisation.


Assuntos
Volume Sanguíneo , Estenose das Carótidas/fisiopatologia , Estenose das Carótidas/cirurgia , Artérias Cerebrais/fisiopatologia , Revascularização Cerebral/métodos , Circulação Cerebrovascular , Angiografia por Ressonância Magnética/métodos , Idoso , Velocidade do Fluxo Sanguíneo , Estenose das Carótidas/patologia , Artérias Cerebrais/patologia , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento
9.
Ann Hepatol ; 12(6): 926-34, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24114823

RESUMO

INTRODUCTION: Gadoxetate-disodium is a liver-specific MR contrast agent absorbed by hepatocytes via organic anion transporting polypeptide 1B3 and is excreted into the biliary system by multidrug resistance-associated protein 2. It has been suggested that relative parenchymal enhancement on hepatocyte phase image is associated with hepatic function. However, it is not clear whether gadoxetate-disodium-enhanced MRI can be used as a noninvasive fibrosis marker. Thus, the purpose of our study was to evaluate the diagnostic performance of gadoxetate-disodium-enhanced MRI in predicting the hepatic fibrosis stage. MATERIALS AND METHODS: A total of 113 patients who had fibrosis staged according to the Batts and Ludwig score were enrolled: F0 (n = 13), F1 (n = 18), F2 (n = 15), F3 (n = 32), and F4 (n = 35). All patients underwent gadoxetate-disodium-enhanced MRI before confirmation by biopsy (n = 67) or surgery (n = 46). For quantitative analysis, the contrast enhancement index (CEI) was calculated by measuring the signal intensity (SI) in liver and paraspinal muscle using a region of interest, as follows: CEI = (liver SI/paraspinal muscle SI) 20 min hepatocyte phase image/(liver SI/paraspinal muscle SI) pre-contrast T1-weighted image. The diagnostic performance was evaluated by the ROC curve, adjusted for the prevalence of each fibrosis stage. RESULTS: A significant negative correlation was observed between CEI and fibrosis stage (r = -0.545, P < 0.0001). The adjusted AUROC for CEI in the prediction of mild (≥F1), moderate (≥ F2), or severe fibrosis (≥ F3) and liver cirrhosis (F4) was 0.668, 0.703, 0.73, and 0.84, respectively. IN CONCLUSION: our results demonstrate that quantitative analysis of relative hepatic enhancement using gadoxetate-disodium-enhanced MRI can predict the hepatic fibrosis stage.


Assuntos
Meios de Contraste , Gadolínio DTPA , Cirrose Hepática/patologia , Fígado/patologia , Imageamento por Ressonância Magnética , Adulto , Idoso , Área Sob a Curva , Biomarcadores/sangue , Biópsia , Feminino , Humanos , Fígado/metabolismo , Fígado/cirurgia , Cirrose Hepática/sangue , Cirrose Hepática/cirurgia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Curva ROC , Estudos Retrospectivos , Índice de Gravidade de Doença
10.
Am J Case Rep ; 24: e938569, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36793200

RESUMO

BACKGROUND Vanishing white matter disease (VWMD) - also known as childhood ataxia with central nervous system hypomyelination - is one of the most commonly inherited white matter diseases in children. Notably, a course of chronic progressive disease with episodes of rapid and major stress-induced neurological deterioration, such as fever and minor head trauma, is a typical clinical feature of VWMD. The combination of clinical features with specific magnetic resonance imaging findings, including diffuse and extensive white matter lesions with rarefaction or cystic destruction, could recommend a genetic diagnosis. However, VWMD is phenotypically diverse and can affect individuals of all ages. CASE REPORT A 29-year-old female patient presented with recent aggravation in gait disturbance. She had progressive movement disorder, with symptoms ranging from hand tremors to upper- and lower-extremity weakness, for 5 years. Whole-exome sequencing was performed to confirm the diagnosis of VWMD, and it revealed a mutation in homozygous eIF2B2 gene. The temporal evolution of VWMD observed in the patient for 17 years (from the age of 12 to 29 years) indicated an increased extent of T2 white matter hyperintensity in the cerebrum into the cerebellum and an increased amount of dark signal intensities in the globus pallidus and dentate nucleus. Moreover, a T2*-weighted imaging (WI) scan revealed diffuse, linear, and symmetrical hypointensity along the juxtacortical white matter on the magnification view. CONCLUSIONS This is the case report about rare and unusual finding of diffuse linear juxtacortical white matter hypointensity on T2*-WI scan as a potential radiographic marker for adult-onset VWMD.


Assuntos
Traumatismos Craniocerebrais , Leucoencefalopatias , Substância Branca , Adulto , Criança , Feminino , Humanos , Adolescente , Adulto Jovem , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Leucoencefalopatias/diagnóstico por imagem , Leucoencefalopatias/genética , Imageamento por Ressonância Magnética/métodos , Cerebelo/patologia
11.
J Yeungnam Med Sci ; 40(2): 136-145, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36624654

RESUMO

Hepatic encephalopathy (HE) is a severe neuropsychiatric abnormality in patients with either acute or chronic liver failure. Typical brain magnetic resonance imaging findings of HE are bilateral basal ganglia high signal intensities due to manganese deposition in chronic liver disease and hyperintensity in T2, fluid-attenuated inversion recovery, or diffusion-weighted imaging (DWI) with hemispheric white matter changes including the corticospinal tract. Low values on apparent diffusion coefficient mapping of the affected area on DWI, indicating cytotoxic edema, can be observed in acute HE. However, neuropsychological impairment in HE ranges from mild deficits in psychomotor abilities affecting quality of life to stupor or coma with higher grades of hepatic dysfunction. In particular, the long-lasting compensatory mechanisms for the altered metabolism in chronic liver disease make HE imaging results variable. Therefore, the clinical relevance of imaging findings is uncertain and differentiating HE from other metabolic diseases can be difficult. The recent introduction of concepts such as "acute-on-chronic liver failure (ACLF)," a new clinical entity, has led to a change in the clinical view of HE. Accordingly, there is a need to establish a corresponding concept in the field of neuroimaging diagnosis. Herein, we review HE from a historical and etiological perspective to increase understanding of brain imaging and help establish an imaging approach for advanced new concepts such as ACLF. The purpose of this manuscript is to provide an understanding of HE by reviewing neuroimaging findings based on pathological and clinical concepts of HE, thereby assisting in neuroimaging interpretation.

12.
Bioengineering (Basel) ; 10(7)2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37508887

RESUMO

Neuropathic pain (NP) following spinal cord injury (SCI) is refractory to pain control strategies, and the underlying neuronal mechanisms remain poorly understood. This study aimed to determine the brain regions engaged in maintaining a spontaneous resting state and the link between those regions and the severity of NP in patients with incomplete SCI. Seventy-three subjects (41 patients and 32 age- and sex-matched healthy controls) participated in this retrospective study. Regarding the neurological level of injury, patients with incomplete SCI experienced at-level or below-level NP. The severity of NP was evaluated using a visual analog scale (VAS), and patients were divided into mild and moderate-severe NP groups based on VAS scores. Graph theory and fractional amplitude of low-frequency fluctuation (fALFF) analyses were performed to compare resting-state functional magnetic resonance imaging (fMRI) analysis results among the three groups. Graph theory analysis was performed through a region of interest (ROI)-to-ROI analysis and then fALFF analysis was performed in the brain regions demonstrating significant differences among the three groups analyzed using the graph theory. We evaluated whether the brain regions showing significant differences using graph theory and fALFF correlated with the VAS scores. Patients with moderate-severe NP showed reduced node degree and fALFF in the left middle frontal gyrus compared with those with mild NP and healthy controls. Furthermore, patients with severe NP demonstrated increased average path lengths and reduced fALFF values in the posterior cingulate gyrus. This study found that changes in intrinsic oscillations of fMRI signals in the middle frontal gyrus and posterior cingulate gyrus were significant considering the severity of NP.

13.
Neuroimage ; 60(2): 1046-54, 2012 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-22273568

RESUMO

In the present study, we report a new method of manganese enhanced magnetic resonance imaging (MEMRI) using intratympanic (IT) manganese administration. We explore Mn²âº uptake from the middle ear cavity into the cochlea through mechanically gated ion channels of the hair cell and also functional auditory tract tracing without the use of excessive auditory stimuli for a long time period outside the scanner. After manganese administration in animals with normal hearing and unilateral deafness, T1-weighted MR images were obtained for up to 48 h with a 3.0 T MR imager. In normal rats, the mean signal-to-noise ratio (SNR) at each region of interest on the auditory pathway was significantly higher in the IT injection group than in the intraperitoneal (IP) injection group (P<0.05). Furthermore, the cochlea showed Mn²âº signal enhancement only in the IT injection group. In unilateral deafness rats, the IT injection of Mn²âº into the deaf-side middle ear cavity demonstrated signal enhancement in the cochlea but not in other auditory structures without axonal transport of Mn²âº along the auditory pathway. On the other hand, the IT injection of Mn²âº into the normal-side middle ear cavity demonstrated that the mean SNRs at the cochlea, cochlear nucleus, superior olivary complex, lateral lemniscus and inferior colliculus were significantly higher in the ipsilateral auditory pathway than in the contralateral pathway (P<0.05). For the IP injection group, the mean SNRs at each auditory structure, except the cochlea, increased bilaterally. In conclusion, the present work demonstrated the potential advantages of a new IT MEMRI over conventional systemic injection strategies in that (i) the functional auditory tract tracing initiated by the hair cell function is possible and (ii) the axonal transport of Mn²âº ions by trans-synaptic activity is possible without auditory stimulation for a long time period outside MR scanner.


Assuntos
Vias Auditivas/fisiologia , Imageamento por Ressonância Magnética/métodos , Manganês , Animais , Surdez/fisiopatologia , Orelha Média , Masculino , Manganês/administração & dosagem , Peritônio , Ratos , Ratos Sprague-Dawley
14.
J Comput Assist Tomogr ; 36(2): 220-5, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22446363

RESUMO

OBJECTIVE: To investigate if there is difference in hepatic segmental volume distribution according to causes of liver cirrhosis (LC) using computed tomography volumetric analysis. METHODS: On computed tomographic scans, hepatic segmental volumes were measured in 90 patients with LC of 4 different causes (alcohol, hepatitis B virus (HBV), hepatitis C virus (HCV), and cryptogenic cirrhosis). The volumetric indices were compared. RESULTS: The volume proportion of the lateral segment in the liver in patients with HBV was significantly higher than in the patients with HCV (P = 0.038). Hepatic volume distribution in alcoholic LC showed differences: larger caudate lobe volume than HBV- and HCV-induced LC (P = 0.029 and P = 0.031), larger right lobe volume (P = 0.043) and smaller proportion of the lateral segment in the liver (P = 0.003) than in HBV-induced LC. CONCLUSIONS: Computed tomography volumetric analysis showed differences in hepatic segmental volume distribution in cirrhotic patients according to causes of LC.


Assuntos
Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/etiologia , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Meios de Contraste , Feminino , Humanos , Iohexol/análogos & derivados , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Estatísticas não Paramétricas
15.
Korean J Radiol ; 23(8): 794-802, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35914744

RESUMO

OBJECTIVE: To evaluate the feasibility of single-shot whole thoracic time-resolved MR angiography (TR-MRA) to identify the feeding arteries of pulmonary arteriovenous malformations (PAVMs) and reperfusion of the lesion after embolization in patients with multiple PAVMs. MATERIALS AND METHODS: Nine patients (8 females and 1 male; age range, 23-65 years) with a total of 62 PAVMs who underwent percutaneous embolization for multiple PAVMs and were subsequently followed up using TR-MRA and CT obtained within 6 months from each other were retrospectively reviewed. All imaging analyses were performed by two independent readers blinded to clinical information. The visibility of the feeding arteries on maximum intensity projection (MIP) reconstruction and multiplanar reconstruction (MPR) TR-MRA images was evaluated by comparing them to CT as a reference. The accuracy of TR-MRA for diagnosing reperfusion of the PAVM after embolization was assessed in a subgroup with angiographic confirmation. The reliability between the readers in interpreting the TR-MRA results was analyzed using kappa (κ) statistics. RESULTS: Feeding arteries were visible on the original MIP images of TR-MRA in 82.3% (51/62) and 85.5% (53/62) of readers 1 and 2, respectively. Using the MPR, the rates increased to 93.5% (58/62) and 95.2% (59/62), respectively (κ = 0.760 and 0.792, respectively). Factors for invisibility were the course of feeding arteries in the anteroposterior plane, proximity to large enhancing vessels, adjacency to the chest wall, pulsation of the heart, and small feeding arteries. Thirty-seven PAVMs in five patients had angiographic confirmation of reperfusion status after embolization (32 occlusions and 5 reperfusions). TR-MRA showed 100% (5/5) sensitivity and 100% (32/32, including three cases in which the feeding arteries were not visible on TR-MRA) specificity for both readers. CONCLUSION: Single-shot whole thoracic TR-MRA with MPR showed good visibility of the feeding arteries of PAVMs and high accuracy in diagnosing reperfusion after embolization. Single-shot whole thoracic TR-MRA may be a feasible method for the follow-up of patients with multiple PAVMs.


Assuntos
Malformações Arteriovenosas , Embolização Terapêutica , Veias Pulmonares , Adulto , Idoso , Angiografia , Fístula Arteriovenosa , Malformações Arteriovenosas/diagnóstico por imagem , Malformações Arteriovenosas/terapia , Embolização Terapêutica/métodos , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Pulmonar/anormalidades , Artéria Pulmonar/diagnóstico por imagem , Artéria Pulmonar/patologia , Veias Pulmonares/anormalidades , Veias Pulmonares/diagnóstico por imagem , Veias Pulmonares/patologia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
16.
NMR Biomed ; 24(4): 366-72, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-22945291

RESUMO

Motor imagery is a mental rehearsal of simple or complex motor acts without overt body movement. It has been proposed that the association between performance and the mental rehearsal period that precedes the voluntary movement is an important point of difference between highly trained athletes and beginners. We compared the activation maps of elite archers and nonarchers during mental rehearsal of archery to test whether the neural correlates of elite archers were more focused and efficiently organised than those of nonarchers. Brain activation was measured using functional MRI in 18 right-handed elite archers and 18 right-handed nonarchers. During the active functional MRI imagery task, the participants were instructed to mentally rehearse their archery shooting from a first-person perspective. The active imagery condition was tested against the nonmotor imagery task as a control condition. The results showed that the premotor and supplementary motor areas, and the inferior frontal region, basal ganglia and cerebellum, were active in nonarchers, whereas elite archers showed activation primarily in the supplementary motor areas. In particular, our result of higher cerebellar activity in nonarchers indicates the increased participation of the cerebellum in nonarchers when learning an unfamiliar archery task. Therefore, the difference in cerebellar activation between archers and nonarchers provides evidence of the expertise effect in the mental rehearsal of archery. In conclusion, the relative economy in the cortical processes of elite archers could contribute to greater consistency in performing the specific challenge in which they are highly practised.


Assuntos
Mapeamento Encefálico , Imagens, Psicoterapia , Atividade Motora/fisiologia , Fenômenos Fisiológicos do Sistema Nervoso , Esportes , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
17.
NMR Biomed ; 24(10): 1392-400, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21472808

RESUMO

Methamphetamine (MA) abusers commonly exhibit socially problematic behaviors, such as diminished empathy, decreased emotional regulation and interpersonal violence, which may be attributable to alterations in emotional experience. However, few studies have used functional MRI to examine directly the emotional experience of threatening or fearful non-face images in MA abusers. In this study, we investigated possible differences in neural correlates of negative emotional experiences between abstinent MA abusers and healthy subjects using complex visual scenes depicting fear or threat derived from the International Affective Picture System. In within-group analyses, healthy subjects and MA abusers activated a similarly distributed cortical network, prominently including the amygdala, fusiform gyrus, parahippocampal gyrus, ventrolateral prefrontal cortex and inferior frontal cortex. In between-group analyses, however, MA abusers showed a reduced activation in the bilateral dorsolateral prefrontal cortex and insula, and increased activation in the fusiform gyrus, hippocampus, parahippocampal gyrus and posterior cingulate cortex, relative to healthy subjects. Hypoactivation of the insula in MA abusers relative to healthy subjects suggests that the ability to have an emotional response to threatening scenes and empathy for another's pain could be compromised in MA abusers. Hyperactivity in the fusiform gyrus, parahippocampal gyrus and posterior cingulate cortex in MA abusers relative to healthy subjects indicates that threatening and fearful images from the International Affective Picture System may remind MA abusers of episodic memory related to similar experiences. Therefore, functional impairment of these neural networks in MA abusers may contribute to altered emotional experience in social interactions, which could lead to increased negative mood and stress in interpersonal communication.


Assuntos
Emoções/fisiologia , Saúde , Imageamento por Ressonância Magnética/métodos , Metanfetamina/efeitos adversos , Rede Nervosa/fisiopatologia , Transtornos Relacionados ao Uso de Substâncias/fisiopatologia , Análise e Desempenho de Tarefas , Adulto , Mapeamento Encefálico , Estudos de Casos e Controles , Demografia , Emoções/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/efeitos dos fármacos
18.
Acta Radiol ; 52(4): 364-71, 2011 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21498298

RESUMO

BACKGROUND: Most ductal carcinoma in situ (DCIS) of the breast is asymptomatic and usually manifests as calcifications in screening mammography. On the other hand, little is known about ultrasonographic (US) features of asymptomatic DCIS, for US is rarely used for the diagnosis and evaluation of DCIS because of low sensitivity in detecting microcalcifications. PURPOSE: To evaluate US detection and characterization of DCIS in asymptomatic women and correlate these imaging findings with the histopathologic features. MATERIAL AND METHODS: This retrospective study evaluated mammographic and US images of 60 DCIS cases from 59 asymptomatic women. US was performed in knowledge of mammographic findings. The following histopathologic parameters were analyzed: Van Nuys classification, architectural pattern, and presence of microinvasion. Image detectability and US features were correlated with these histopathologic parameters. RESULTS: Of the 54 cases (90.0%) detected on mammography, 48 cases (88.9%) had microcalcifications only, 5 (9.3%) had microcalcifications with associated density, and 1 (1.9%) had soft tissue density alone. Of the 38 cases (63.3%) identified by US, 29 cases (76.3%) had a mass with or without microcalcifications, six (15.8%) had microcalcifications only, and three (7.9%) had other findings. US identified lesions were associated with higher Van Nuys groups, microinvasion and comedocarcinoma (P = 0.044, P = 0.024, and P = 0.032, respectively). The most common US finding was a not-circumscribed, oval mass with parallel orientation and normal acoustic transmission. Microcalcifications were seen on US in 31 (81.6%) of the 38 US visible cases; this finding showed a trend of association with Van Nuys group 2 and 3 but was not statistically significant (P = 0.063). CONCLUSION: When DCIS was identified on US, it was associated with more aggressive histopathologic type. However, mammographic correlation is essential to differentiate benign from malignant lesion in cases seen by US; US findings of asymptomatic DCIS had a low suspicion of malignancy.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Carcinoma in Situ/diagnóstico por imagem , Carcinoma in Situ/patologia , Carcinoma Ductal de Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Calcinose , Feminino , Humanos , Mamografia , Pessoa de Meia-Idade , Estudos Retrospectivos , Ultrassonografia Mamária
19.
Technol Health Care ; 29(S1): 35-48, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33682743

RESUMO

BACKGROUND: Post-stroke depression (PSD) is a consequential neuropsychiatric sequela that occurs after stroke. However, the pathophysiology of PSD are not well understood yet. OBJECTIVE: To explore alterations in functional connectivity (FC) between anterior insula and fronto-cortical and other subcortical regions in the non-affected hemisphere in patients with PSD compared to without PSD and healthy control. METHODS: Resting-state FC was estimated between the anterior insula and cortical and subcortical brain regions in the non-affected hemisphere in 13 patients with PSD, 12 patients without PSD, and 13 healthy controls. The severity of depressive mood was measured by the Beck Depression Inventory (BDI)-II. RESULTS: Patients with PSD showed significant differences in FC scores between the anterior insula and the superior frontal, middle frontal, and orbitofrontal gyrus in the non-affected hemisphere than healthy control or patients without PSD (P< 0.05). In post-hoc, patients with PSD showed higher FC scores between the anterior insula and the superior frontal region than patients without PSD (P< 0.05). Furthermore, alterations in FC of the superior frontal, middle frontal, and orbitofrontal gyrus were positively correlated with depression severity, as measured with the BDI-II (P< 0.001).


Assuntos
Depressão , Imageamento por Ressonância Magnética , Acidente Vascular Cerebral , Idoso , Encéfalo , Mapeamento Encefálico , Depressão/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem
20.
Int J Biol Sci ; 17(14): 3818-3836, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34671201

RESUMO

Rationale: In intracranial arterial dolichoectasia (IADE) development, the feedback loop between inflammatory cytokines and macrophages involves TNF-α and NF-κB signaling pathways and leads to subsequent MMP-9 activation and extracellular matrix (ECM) degeneration. In this proof-of-concept study, melittin-loaded L-arginine-coated iron oxide nanoparticle (MeLioN) was proposed as the protective measure of IADE formation for this macrophage-mediated inflammation and ECM degeneration. Methods: IADE was created in 8-week-old C57BL/6J male mice by inducing hypertension and elastase injection into a basal cistern. Melittin was loaded on the surface of ION as a core-shell structure (hydrodynamic size, 202.4 nm; polydispersity index, 0.158). Treatment of MeLioN (2.5 mg/kg, five doses) started after the IADE induction, and the brain was harvested in the third week. In the healthy control, disease control, and MeLioN-treated group, the morphologic changes of the cerebral arterial wall were measured by diameter, thickness, and ECM composition. The expression level of MMP-9, CD68, MCP-1, TNF-α, and NF-κB was assessed from immunohistochemistry, polymerase chain reaction, and Western blot assay. Results: MeLioN prevented morphologic changes of cerebral arterial wall related to IADE formation by restoring ECM alterations and suppressing MMP-9 expression. MeLioN inhibited MCP-1 expression and reduced CD68-positive macrophage recruitments into cerebral arterial walls. MeLioN blocked TNF-α activation and NF-κB signaling pathway. In the Sylvian cistern, co-localization was found between the CD68-positive macrophage infiltrations and the MeLioN distributions detected on Prussian Blue and T2* gradient-echo MRI, suggesting the role of macrophage harboring MeLioN. Conclusions: The macrophage infiltration into the arterial wall plays a critical role in the MMP-9 secretion. MeLioN, designed for ION-mediated melittin delivery, effectively prevents IADE formation by suppressing macrophage-mediated inflammations and MMP activity. MeLioN can be a promising strategy preventing IADE development in high-risk populations.


Assuntos
Artérias Cerebrais/patologia , Transtornos Cerebrovasculares/prevenção & controle , Inflamação/prevenção & controle , Macrófagos/fisiologia , Nanopartículas de Magnetita/uso terapêutico , Meliteno/administração & dosagem , Animais , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Transtornos Cerebrovasculares/patologia , Quimiocina CCL2/antagonistas & inibidores , Quimiocina CCL2/metabolismo , Modelos Animais de Doenças , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismo
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