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1.
Nihon Hoshasen Gijutsu Gakkai Zasshi ; 80(1): 56-65, 2024 Jan 20.
Artigo em Japonês | MEDLINE | ID: mdl-38008461

RESUMO

The three-dimensional time-of-flight (3D-TOF), which is currently the most common acquisition technique of intracranial magnetic resonance angiography (MRA), may result in poor branch visualization due to reduced blood flow velocity. Proton density-weighted volume isotropic turbo spin-echo acquisition (PDVISTA) is less susceptible to these factors and has been reported to be useful in assessing cerebral vasospasm after subarachnoid hemorrhage. In this study, we investigated the effect of refocus flip angle (RFA) for PDVISTA on the contrast between blood vessels and background brain tissue using flow velocity phantom and clinical images, assuming the usefulness of PDVISTA in daily clinical practice. The phantom experiments showed that the contrast ratio significantly improved with decreasing RFA; however, considering the signal-to-noise ratio, RFA 80° was determined as optimal for clinical use. Visual assessment was performed on PDVISTA (RFA 80°) and conventional 3D-TOF MRA clinical images, which suggested the superiority of PDVISTA over 3D-TOF in the delineation of peripheral branches of cerebral vessels. The results suggest that PDVISTA is useful not only for subarachnoid hemorrhage patients but also in daily clinical practice.


Assuntos
Angiografia por Ressonância Magnética , Hemorragia Subaracnóidea , Humanos , Angiografia por Ressonância Magnética/métodos , Prótons , Imageamento Tridimensional/métodos , Razão Sinal-Ruído
2.
J Neurol Sci ; 423: 117366, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33714084

RESUMO

INTRODUCTION: Despite great progress in radiological diagnostic tools for neurodegenerative disorders, their diagnostic accuracy has been unsatisfactory. One of the pathological hallmarks of progressive supranuclear palsy (PSP) is atrophy of the subthalamic nucleus, which has not attracted much attention for imaging analysis. METHODS: The clinical data of patients with PSP, multiple system atrophy (MSA), Parkinson's disease (PD), and corticobasal syndrome (CBS) who underwent brain magnetic resonance imaging at our department between June 2019 and March 2020 were retrospectively reviewed. The volumes of the subthalamic nucleus and of the whole cerebrum were then analyzed and compared among the disorders. RESULTS: Fourteen PSP-Richardson syndrome (RS), 14 MSA, 14 PD, and 8 CBS patients were assessed. The mean volume of the bilateral subthalamic nuclei was smaller in PSP patients (0.148 ± 0.012 cm3) than in MSA (0.183 ± 0.026 cm3; p < 0.001), PD (0.209 ± 0.031 cm3; p < 0.001), and CBS (0.180 ± 0.056 cm3; p < 0.001) patients. The volume of the whole cerebrum was not significantly different among the disorders. Using an STN volume cut-off of 0.01925, the sensitivity and specificity for differential diagnosis between PSP and the other disorders were 0.846 and 0.972, respectively. CONCLUSION: Subthalamic nucleus volume may be a useful diagnostic marker for PSP; it may easily differentiate it from other neurodegenerative parkinsonian disorders.


Assuntos
Atrofia de Múltiplos Sistemas , Núcleo Subtalâmico , Paralisia Supranuclear Progressiva , Atrofia , Diagnóstico Diferencial , Humanos , Imageamento por Ressonância Magnética , Atrofia de Múltiplos Sistemas/diagnóstico por imagem , Estudos Retrospectivos , Paralisia Supranuclear Progressiva/diagnóstico por imagem
3.
Medicine (Baltimore) ; 100(2): e24193, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33466194

RESUMO

ABSTRACT: There is a growing need for tissue collection for immunostaining and genetic testing. Recently, several fine-needle biopsy needles are commercially available for endoscopic ultrasound-guided tissue acquisition.This prospective historical controlled study evaluates a 20G core biopsy needle with a forward bevel for solid pancreatic masses larger than 15 mm in diameter. The primary endpoint was the accuracy of histological diagnosis. The secondary endpoints included technical success rate, sample adequacy for histology, cytological diagnostic accuracy, and adverse events.Seventy consecutive patients were enrolled between January and October 2017. We achieved technical success in all cases regardless of the puncture sites or the endosonographer's experience. The final diagnoses were neoplasms in 67 patients (95.7%; pancreatic cancer in 65 patients, neuroendocrine neoplasm in 1, and malignant lymphoma in 1) and benign lesions in 3 patients (4.3%; autoimmune pancreatitis in 2 patients and mass-forming pancreatitis in 1). The obtained specimens were adequate for histological evaluation in all cases and the histological accuracy was 91.4% (95% confidence interval, 82.3-96.8%, P < .05) with the sensitivity and specificity of 91.0% and 100%, respectively. The cytological diagnostic accuracy was 95.7% and all patients were accurately diagnosed by combining cytological and histological examinations. As for adverse events, an asymptomatic needle fracture occurred in 1 case (1.4%).This 20G core biopsy needle with a forward bevel showed a high accuracy of histological diagnosis for solid pancreatic masses.


Assuntos
Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Pâncreas/anormalidades , Pâncreas/patologia , Pâncreas/cirurgia , Adulto , Idoso , Biópsia/métodos , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/normas , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/patologia , Estudos Prospectivos
4.
Jpn J Radiol ; 39(2): 198-205, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32939741

RESUMO

PURPOSE: The Cingulate Island Sign score (CIScore) by rCBF SPECT is used in the differentiation between Dementia with Lewy bodies (DLB) and Alzheimer's disease (AD) but has some false-positive AD cases. To resolve the problem, we developed new differential diagnosing method incorporating occipital lobe and para-hippocampal rCBF. MATERIALS AND METHODS: In 27 DLB and 31 AD cases undertaken Tc-99 m-ECD SPECT, we evaluated the mean Z score in the bilateral superior, middle, inferior occipital gyri, cuneus, amygdala, hippocampus, and para-hippocampus. One criterion of DLB was defined as the case with CIScore lower than 0.27. The other criteria were the cases of following either or both two conditions were satisfied. (1) The number of occipital gyri with mean Z score higher than 1 is three or more. (2) The number of hippocampal regions with mean Z score higher than 1 is one or less. We compared the differential diagnostic ability among these four criterions. RESULTS: The diagnostic accuracy by CIscore was 69% and that of the occipital gyri analysis 84%, para-hippocampal regions analysis 76% and combined occipital gyri and para-hippocampal regions analysis 93%. CONCLUSION: The new method by combined rCBF analysis of occipital gyri and para-hippocampal regions showed best diagnostic ability in differentiating DLB from AD.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Doença por Corpos de Lewy/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Idoso , Idoso de 80 Anos ou mais , Encéfalo/irrigação sanguínea , Encéfalo/efeitos dos fármacos , Circulação Cerebrovascular , Diagnóstico Diferencial , Feminino , Humanos , Tecnécio
5.
Cerebrovasc Dis Extra ; 9(1): 25-30, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31039570

RESUMO

BACKGROUND/PURPOSE: Because atherosclerotic factors and antithrombotic agents sometimes induce cerebral microbleeds (CMBs), patients with cerebral large artery disease (CLAD) tend to have more CMBs than control subjects. On the other hand, VEGF contributes to the disruption of the blood-brain barrier, and it may induce parenchymal edema and bleeding. We conducted a study to evaluate the role of vascular endothelial growth factor (VEGF) in the occurrence of CMBs in patients with CLAD. METHODS: CLAD is defined as stenosis or occlusion of either the carotid artery or the middle cerebral artery of 50% or more. We prospectively registered patients with CLAD who were hospitalized in our neurocenter. Biological backgrounds, atherosclerotic risk factors, administration of antithrombotics before hospitalization, and levels of cytokines and chemokines were evaluated. Susceptibility-weighted imaging or T2*-weighted MR angiography was used to evaluate CMBs. The Brain Observer MicroBleed Scale (BOMBS) was used for CMB assessments. Images were analyzed with regard to the presence or absence of CMBs. We also examined plasma VEGF concentrations using a commercial ELISA kit. Because more than half showed plasma VEGF levels below assay detection limits (3.2 pg/mL), the patients were dichotomized by plasma VEGF levels into two groups (above and below the detection limit). After univariate analyses, logistic regression analysis was conducted to determine the factors associated with the CMBs after adjustment for age, sex, the presence of hypertension, and administration of antithrombotic agents. A similar analysis with CMBs separated by location (cortex, subcortex, or posterior circulation) was also conducted. RESULTS: Sixty-six patients (71.1 ± 8.9 years, 53 males and 13 females) were included in this study. Plasma VEGF levels were not correlated with age, sex, and atherosclerotic risk factors; however, patients with VEGF levels >3.2 pg/mL tended toward more frequent CMBs (60.0 vs. 32.6%, in the presence and absence of CMBs, p = 0.056). With regard to the location of CMBs, those in the cortex and/or at the gray-white junction were observed more frequently in the patients with VEGF levels >3.2 pg/mL after multivariable analyses (odds ratio: 3.80; 95% confidence interval: 1.07-13.5; p = 0.039). CONCLUSIONS: In patients with CLAD, elevated plasma VEGF might be associated with CMBs, especially those located in the cortex and/or at the gray-white junction.


Assuntos
Estenose das Carótidas/sangue , Doenças Arteriais Cerebrais/sangue , Hemorragia Cerebral/sangue , Fator A de Crescimento do Endotélio Vascular/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Angiografia Cerebral/métodos , Doenças Arteriais Cerebrais/complicações , Doenças Arteriais Cerebrais/diagnóstico por imagem , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/etiologia , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Regulação para Cima
6.
J Stroke Cerebrovasc Dis ; 28(5): 1192-1199, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30711415

RESUMO

BACKGROUND: There are limited clinical studies of bilateral vertebral artery dissection (VAD). OBJECTIVE: To compare the characteristics, imaging findings, and treatments between patients with bilateral and unilateral VAD. METHODS: Between February 2007 and May 2017, 31 (mean age: 53.0 years; 23 men, 8 women) out of 171 VAD patients were hospitalized because of bilateral VAD. Onset type, dissection site, dominant side of the VA, imaging features, treatments, and outcomes were investigated based on medical records. The dominant side of the VA was determined by basi-parallel anatomical scanning. RESULTS: Twenty (64.5%) of 31 patients exhibited bilateral VAD on both sides of V4. The dominant side of the VA was right in 16 patients and left in 15 patients. The pearl and string sign (an angiographical finding with both dilatation and stenosis) was frequently observed on the dominant VAD side, while a tapered occlusion and string sign were most common on the nondominant side. For clinical subtype of VAD, 6 (19.4%) patients had subarachnoid hemorrhage, 10 (32.3%) ischemic stroke, 3 (9.7%) infarction plus subarachnoid hemorrhage, and 12 (38.7%) only headache. The frequency of infarction was increased in bilateral VAD compared with unilateral (P < .05). Surgical intervention was performed in 3 cases, while 14 patients received endovascular intervention. CONCLUSIONS: Infarction occurred frequently in bilateral VAD patients, and 17 patients required an intervention (mainly endovascular) for VA. The treatment strategy varied depending on the clinical subtype, imaging findings of VAD, and morphology of the dominant VAD side.


Assuntos
Angiografia Digital , Angiografia Cerebral/métodos , Procedimentos Endovasculares , Fármacos Hematológicos/uso terapêutico , Procedimentos Neurocirúrgicos , Dissecação da Artéria Vertebral/diagnóstico por imagem , Dissecação da Artéria Vertebral/terapia , Artéria Vertebral/diagnóstico por imagem , Adulto , Idoso , Anticoagulantes/uso terapêutico , Infarto Encefálico/diagnóstico por imagem , Infarto Encefálico/etiologia , Infarto Encefálico/terapia , Tomada de Decisão Clínica , Feminino , Fibrinolíticos/uso terapêutico , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/uso terapêutico , Valor Preditivo dos Testes , Fatores de Risco , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Subaracnóidea/etiologia , Hemorragia Subaracnóidea/terapia , Resultado do Tratamento , Dissecação da Artéria Vertebral/complicações
7.
J Magn Reson Imaging ; 49(3): 800-807, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30284331

RESUMO

BACKGROUND: Black-blood MR angiography (BBMRA), which utilizes a non-T1 contrast spin-echo type technique, has been expected to overcome several issues associated with time-of-flight (TOF) MRA. PURPOSE: To investigate the efficacy of BBMRA to detect vasospasms following subarachnoid hemorrhage (SAH). STUDY TYPE: Retrospective. SUBJECTS: Seventeen patients with SAH in their early posttreatment period. FIELD STRENGTH/SEQUENCE: BBMRA, which uses a volumetric isotropic turbo spin-echo acquisition (VISTA), and TOF-MRA on 1.5T scanners. ASSESSMENT: Visualization of supratentorial arteries and veins in BBMRA was rated on a 4-point scale by two neuroradiologists. Another neuroradiologist independently assessed TOF-MRA. The degree of the vasospasm was then evaluated using a 3-point scale by the same readers. The diagnostic performance of the MRAs was evaluated using computed tomography angiography (CTA) or digital subtraction angiography (DSA) as the standard of reference. STATISTICAL TESTS: Wilcoxon signed rank test, McNemar test, and Cohen's kappa coefficient. RESULTS: BBMRA provided superior visualization of the anterior and middle cerebral arteries than TOF-MRA (P < 0.05). The depiction of the veins was more pronounced on BBMRA (P < 0.01). Of the 166 arterial segments evaluated by CTA or DSA, 23 (13.9%) could not be assessed using TOF-MRA because of high signal hemorrhage, whereas BBMRA enabled visualization of all the segments. Vasospasm was confirmed in 30 segments by CTA or DSA. The sensitivity, specificity, and positive and negative predictive values were 73, 96, 76, and 95 for TOF-MRA and 91, 100, 100, and 98 for BBMRA, respectively (P = 0.13 for sensitivity, P = 0.06 for specificity). The agreement of the degree of vasospasm between MRA and the standard of reference, as indicated by kappa value, was 0.71 (95% confidence interval [CI], 0.55-0.87) for TOF-MRA and 0.91 (95% CI, 0.82-0.99) for BBMRA. DATA CONCLUSION: BBMRA, owing to its contrast properties, may be superior to TOF-MRA for the evaluation of intracranial arteries after SAH. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:800-807.


Assuntos
Imageamento Tridimensional , Imageamento por Ressonância Magnética , Hemorragia Subaracnóidea/diagnóstico por imagem , Vasoespasmo Intracraniano/diagnóstico por imagem , Idoso , Angiografia Digital , Artérias Carótidas/diagnóstico por imagem , Angiografia Cerebral , Circulação Cerebrovascular , Angiografia por Tomografia Computadorizada , Meios de Contraste/química , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos Retrospectivos
8.
J Clin Neurosci ; 48: 76-80, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29257748

RESUMO

Vertebral artery dissection (VAD) has been recognized as a cause of headache and stroke. Accurate evaluation of dissection using several modalities such as catheter-based angiography, CT angiography (CTA), and magnetic resonance imaging (MRI) is essential for subsequent management. The aim of this retrospective study is to compare cone-beam computed tomography angiography (CBCT-A) with other image modalities for the evaluation of the detailed structures of VAD. Twenty-five consecutive cases identified as having VAD were included. They underwent catheter-based angiography (2D-digital subtraction angiography [DSA], 3D-DSA, and CBCT-A), CTA, and MRI for the diagnosis of VAD. CBCT-A was performed following conventional angiography. Dissecting lesions were evaluated for the presence of intimal flap/double lumen, wall thickening, and enhancement of outer wall. This study results showed that CBCT-A was the most superior modality to detect intimal flap/double lumen (found in 56% of the cases) due to its high spatial resolution. MRI was superior for the assessment of wall thickening as an intramural hematoma in 76% of the cases. However, wall thickening was detected in 44% of cases using CBCT-A. In 5 cases, enhancement of outer wall was identified only in CBCT-A. In conclusion, CBCT-A provides detailed luminal and wall morphology of VADs. CBCT-A is useful for the accurate diagnosis of VADs.


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Dissecação da Artéria Vertebral/diagnóstico por imagem , Adulto , Idoso , Angiografia Digital , Angiografia Cerebral , Feminino , Hematoma/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Artéria Vertebral/diagnóstico por imagem , Dissecação da Artéria Vertebral/diagnóstico
9.
J Stroke Cerebrovasc Dis ; 27(2): 321-325, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29030047

RESUMO

BACKGROUND: The association of carotid plaque enhancement on contrast-enhanced carotid ultrasound (CEUS) and plaque vulnerability evaluated by magnetic resonance imaging (MRI) was to be determined. MATERIALS AND METHODS: The 103 patients underwent CEUS from May 2013 until June 2016. CEUS images of the carotid plaque were obtained offline. Plaque images obtained at 1, 3, 5, and 10 minutes were compared with the reference image, defined as the image obtained at 0 minute. Plaque brightness was assessed using the gray-scale median during contrast enhancement (GSM-C). Plaque vulnerability was evaluated using T1- and T2-weighted MRI and Volume ISotropic TSE Acquisition (VISTA), with a VISTA cutoff value for the plaque muscle ratio (PMR) of 1.5. Time-dependent changes in the GSM-C were evaluated, and those between 0 and 1 minute were compared with the PMR values determined on MRI. FINDINGS: GSM-C decreased significantly over time, from 32.0 at 0 minute to 28.0 at 1 minute, 25.0 at 3 minutes, and 19.0 at 10 minutes. The greater the increase in the changes in the GSM-C from 0 to 1 minute, the more significant the association with a PMR higher than the median on T1 (GSM-C: 0 minute: 29.0, 1 minute: 24.0, P = .015), a PMR less than or equal to the median on T2 (0 min: 35.0, 1 min: 28.0, P = .003), and a PMR more than 1.5 determined on VISTA (GSM-C: 0 minute: 29.0, 1 minute: 24.0, P = .005). CONCLUSIONS: Early changes in the GSM-C evaluated with CEUS indicate significant plaque vulnerability on MRI.


Assuntos
Artérias Carótidas/diagnóstico por imagem , Estenose das Carótidas/diagnóstico por imagem , Meios de Contraste/administração & dosagem , Placa Aterosclerótica , Ultrassonografia/métodos , Idoso , Artérias Carótidas/patologia , Estenose das Carótidas/patologia , Progressão da Doença , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Ruptura Espontânea , Fatores de Tempo
10.
BJR Case Rep ; 3(1): 20160090, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-30363318

RESUMO

Vogt-Koyanagi-Harada (VKH) disease is an autoimmune disorder that occurs in the melanocytes present in the uvea, leptomeninges, skin and inner ear. Clinically, this disease is characterized by bilateral uveitis and retinal detachment and is associated with meningismus and hearing loss. Gadolinium (Gd)-enhanced MRI may aid in demonstrating bilateral choroidal thickening and central nervous system involvement. We present a case of VKH where Gd-enhanced three-dimensional (3D) fluid attenuation inversion recovery (FLAIR) imaging showed abnormal bilateral enhancement in the inner ears. A 36-year-old female was referred to our institution with symptoms of visual disturbance, headache and tinnitus, and was diagnosed with VKH based on fundus examination and clinical presentations. MRI findings revealed bilateral enhancement in the choroid, leptomeninges, and inner ears. In particular, Gd-enhanced 3D FLAIR showed more conspicuous enhancement of the leptomeninges and inner ear compared with Gd-enhanced 3D T 1 weighted image. Therefore, Gd-enhanced 3D FLAIR imaging can be used when leptomeningeal or inner ear pathology is clinically suspected.

11.
Eur J Radiol ; 86: 13-19, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28027739

RESUMO

PURPOSE: We investigated the enhancement of the intracranial arterial walls with gadolinium-enhanced, black-blood three-dimensional T1-weighted imaging (Gd-3DBB) by using an improved motion-sensitized driven-equilibrium (iMSDE)-prepared volumetric isotropic turbo spin-echo acquisition (VISTA). METHODS: A total of 115 patients underwent FLAIR, 3D-TOF-MRA and Gd-3DBB with a 1.5-T scanner. The degree and distribution of the arterial wall enhancement on Gd-3DBB was assessed. The association of the degree of wall enhancement with brain infarction/ischemic lesions on FLAIR, luminal changes on 3D-TOF-MRA, and cardiovascular risk factors (CVRFs) was investigated by univariate and multiple logistic regression analyses. RESULTS: Strong enhancement of the arterial walls was observed in 77 vertebral arteries (33.5%), 4 basilar arteries (3.5%), 31 supraclinoid internal carotid arteries (ICAs) (13.5%) and 8 middle cerebral arteries (3.5%). In addition, 221 intrapetrous ICAs (96.1%) showed strong enhancement. After adjusting for confounding factors, multivariate analyses showed that the patient age was independently associated with the strong wall enhancement of the arteries for both the posterior (OR, 1.088; 95% CI, 1.034-1.146) and the anterior circulation (OR, 1.098, 95% CI 1.029-1.172). In addition, the presence of the supratentorial brain infarctions was independently associated with the strong wall enhancement in the anterior circulation excluding the intrapetrous ICAs (OR, 4.097; 95% CI, 1.483-11.319). CONCLUSIONS: Although the arterial wall enhancement on the Gd-3DBB probably reflects normal aging, the enhancement in the anterior circulation might be related to brain infarctions. On the other hand, the intrapetrous ICA enhancement is considered a nonspecific finding and should not be mistaken for arterial pathologies such as atherosclerosis or arteritis.


Assuntos
Arteriosclerose Intracraniana/patologia , Angiografia por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Artéria Basilar/patologia , Encéfalo/patologia , Artéria Carótida Interna/patologia , Meios de Contraste , Feminino , Gadolínio , Humanos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/patologia , Estudos Retrospectivos , Fatores de Risco , Artéria Vertebral/patologia
12.
Magn Reson Med Sci ; 16(1): 73-77, 2017 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-27725575

RESUMO

PURPOSE: To elucidate whether any differences are present in the stiffness map obtained with a multiscale direct inversion algorithm (MSDI) vs that with a multimodel direct inversion algorithm (MMDI), both qualitatively and quantitatively. MATERIALS AND METHODS: The MR elastography (MRE) data of 37 consecutive patients who underwent liver MR elastography between September and October 2014 were retrospectively analyzed by using both MSDI and MMDI. Two radiologists qualitatively assessed the stiffness maps for the image quality in consensus, and the measured liver stiffness and measurable areas were quantitatively compared between MSDI and MMDI. RESULTS: MMDI provided a stiffness map of better image quality, with comparable or slightly less artifacts. Measurable areas by MMDI (43.7 ± 17.8 cm2) was larger than that by MSDI (37.5 ± 14.7 cm2) (P < 0.05). Liver stiffness measured by MMDI (4.51 ± 2.32 kPa) was slightly (7%), but significantly less than that by MSDI (4.86 ± 2.44 kPa) (P < 0.05). CONCLUSION: MMDI can provide stiffness map of better image quality, and slightly lower stiffness values as compared to MSDI at 3T MRE, which radiologists should be aware of.


Assuntos
Algoritmos , Técnicas de Imagem por Elasticidade/métodos , Processamento de Imagem Assistida por Computador/métodos , Hepatopatias/diagnóstico por imagem , Hepatopatias/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Artefatos , Feminino , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos
13.
Ann Nucl Med ; 30(9): 637-644, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27438050

RESUMO

OBJECTIVE: The aim of this study is to establish the optimal regions of interest (ROIs) in anatomically normalized I-123 FP-CIT SPECT images for the quantification of dopamine transporter binding. METHODS: The subjects comprised 16 normal controls and 14 Parkinsonian patients. All of the normal control subjects underwent I-123 FP-CIT SPECT and MRI. The SPECT device used in this study was a Toshiba GCA-9300R with triple head detectors. I-123 FP-CIT (148 MBq) was intravenously administered as a bolus, and the SPECT scan started 4 h after the administration. The data were collected over 20 min for each subject, and reconstructed using a 3D-OSEM algorithm. The data were analyzed using SPM8. I-123 FP-CIT SPECT images were anatomically normalized to the MNI space using an I-123 FP-CIT template, and then divided by the background counts automatically measured using the ROIs set for the cerebral cortices. RESULTS: In the normal control subjects, the specific binding ratios of the MRI-based ROIs were lowest in the caudate nucleus, while the ratios of the I-123 FP-CIT-based ROIs were almost the same throughout all three parts. In contrast, in Parkinsonian patients, the specific binding ratios of the I-123 FP-CIT-based ROIs revealed rostrocaudal decline, while those of the MRI-based ROIs were highest in the anterior putamen. CONCLUSION: We created an ROI template on the anatomically normalized MRI and I-123 FP-CIT images, and concluded that I-123 FP-CIT-based ROIs are more suitable for obtaining quantitative values than MRI-based ones.


Assuntos
Anatomia , Tomografia Computadorizada de Emissão de Fóton Único/normas , Tropanos , Adulto , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Parkinsonianos/diagnóstico por imagem , Transtornos Parkinsonianos/metabolismo
14.
No Shinkei Geka ; 44(5): 397-402, 2016 May.
Artigo em Japonês | MEDLINE | ID: mdl-27166845

RESUMO

Calvarial intraosseous schwannoma is very rare bone tumor. Herein we report the case of a 24-year-old woman with an intraosseous schwannoma of the right frontoparietal bone. The patient had a minor head trauma caused by a traffic accident. The patient was examined by a brain computed tomography (CT) and accidentally found a calvarial bone tumor. On local examination, there was no scalp swelling and tenderness. Magnetic resonance imaging (MRI) showed isointensity of the tumor within the brain cortex on T1-weighted image (WI) and high intensity on T2-WI. On the diffusion-weighted images, the isointensity of the tumor was again depicted. The mass was strongly enhanced by gadolinium administration. Subsequently, the tumor was totally removed and was yellowish, well demarcated, and situated in the diploë intraoperatively. The inner table was widely erosive and there was a mild adhesion between the mass and the dura mater. The pathological diagnosis was an intraosseous schwannoma. We reviewed previous reports and discussed.


Assuntos
Neurilemoma/diagnóstico , Neoplasias Cranianas/diagnóstico , Feminino , Humanos , Imageamento por Ressonância Magnética , Imagem Multimodal , Neurilemoma/cirurgia , Prognóstico , Neoplasias Cranianas/cirurgia , Tomografia Computadorizada por Raios X , Adulto Jovem
15.
Ann Nucl Med ; 30(7): 477-83, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27225162

RESUMO

OBJECTIVE: The aim of this study was to create a new template for the anatomical normalization of I-123 FP-CIT SPECT images of Japanese people to evaluate dopamine transporter binding. METHODS: The subjects consisted of 16 normal control subjects (5 females and 11 males; mean age ± SD, 51.6 ± 9.5 years, ranging from 25 to 62 years) and 21 parkinsonian patients (7 females and 14 males; mean age ± SD, 70.7 ± 9.4 years, ranging from 49 to 85 years). All normal control subjects and 21 patients with parkinsonism underwent MRI. A total of 148 MBq of I-123 FP-CIT was intravenously injected as a bolus, and a SPECT scan was started 4 h later. Data were analyzed with the Statistical Parametric Mapping 8 (SPM8) software. At first, I-123 FP-CIT SPECT images were co-registered to MRI images and MRI images were normalized to Montreal Neurological Institute (MNI) space using a gray.nii template. Co-registered I-123 FP-CIT SPECT images were normalized using the predetermined normalization parameters for MRI images. Then, anatomically normalized I-123 FP-CIT SPECT images were divided by background counts individually measured using ROIs set on the cerebral cortices. The I-123 FP-CIT template was created by averaging the normalized SPECT images of the 16 normal control subjects. Thereafter, the averaged MRI images of the 16 normal control subjects were also created. RESULTS: A visual inspection revealed that there were no apparent differences between the I-123 FP-CIT images subjected to the two methods of anatomical normalization in normal control subjects. However, a group comparison by a paired t test using SPM8 revealed that the I-123 FP-CIT binding was significantly higher in the substriatal and temporal regions in I-123 FP-CIT images directly normalized with the I-123 FP-CIT template than in those normalized by the predetermined parameters with MRI, while it was higher in the bilateral frontal cortical regions in the latter than in the former images. CONCLUSION: We successfully created an I-123 FP-CIT template for Japanese people. This template is thought to be useful and reliable for the statistical analysis of I-123 FP-CIT images, although some problems exist in the evaluation of parkinsonian patients. The results of a paired t test using SPM suggest that we should use the same normalization method in statistical image analyses.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Transtornos Parkinsonianos/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Tropanos , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
16.
Eur Radiol ; 26(3): 656-63, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26060066

RESUMO

OBJECTIVES: To clarify the usefulness of 3.0-T MR elastography (MRE) in diagnosing the histological grades of liver fibrosis using preliminary clinical data. MATERIALS AND METHODS: Between November 2012 and March 2014, MRE was applied to all patients who underwent liver MR study at a 3.0-T clinical unit. Among them, those who had pathological evaluation of liver tissue within 3 months from MR examinations were retrospectively recruited, and the liver stiffness measured by MRE was correlated with histological results. Institutional review board approved this study, waiving informed consent. RESULTS: There were 70 patients who met the inclusion criteria. Liver stiffness showed significant correlation with the pathological grades of liver fibrosis (rho = 0.89, p < 0.0001, Spearman's rank correlation). Areas under the receiver operating characteristic curve were 0.93, 0.95, 0.99 and 0.95 for fibrosis score greater than or equal to F1, F2, F3 and F4, with cut-off values of 3.13, 3.85, 4.28 and 5.38 kPa, respectively. Multivariate analysis suggested that grades of necroinflammation also affected liver stiffness, but to a significantly lesser degree as compared to fibrosis. CONCLUSIONS: 3.0-T clinical MRE was suggested to be sufficiently useful in assessing the grades of liver fibrosis. KEY POINTS: MR elastography may help clinicians assess patients with chronic liver diseases. Usefulness of 3.0-T MR elastography has rarely been reported. Measured liver stiffness correlated well with the histological grades of liver fibrosis. Measured liver stiffness was also affected by necroinflammation, but to a lesser degree. 3.0-T MRE could be a non-invasive alternative to liver biopsy.


Assuntos
Imagem Ecoplanar/métodos , Técnicas de Imagem por Elasticidade/métodos , Cirrose Hepática/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Biópsia por Agulha/métodos , Imagem Ecoplanar/estatística & dados numéricos , Elasticidade , Técnicas de Imagem por Elasticidade/estatística & dados numéricos , Feminino , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/patologia , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/patologia , Humanos , Fígado/patologia , Cirrose Hepática/classificação , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Necrose , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade
17.
Chem Commun (Camb) ; 51(24): 4981-4, 2015 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-25583688

RESUMO

Reaction of [(η(6)-C6Me6)RuCl(Ph)(PMe3)] with internal alkynes in the presence of NaBAr(F)4 gave rise to the 1,4-Ru migration to form the o-vinylaryl complex, providing the first example of 1,4-metal migration of a group 8 metal center; in one case further isomerization to an η(3)-allyl complex was observed.

18.
Jpn J Clin Oncol ; 45(1): 61-6, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25341546

RESUMO

OBJECTIVE: Recent studies suggest that systemic inflammatory response is closely associated with cancer patient prognosis. Although several inflammatory prognostic markers have been proposed, the data to support their validity are lacking in large Japanese cohorts. METHODS: This is a retrospective study to examine the prognostic value of inflammatory markers, such as C-reactive protein, neutrophil-lymphocyte ratio, platelet-lymphocyte ratio and modified Glasgow prognostic scale, in pancreatic cancer. Selection criteria were admittance to hospital between January 2008 and December 2012, histologically confirmed adenocarcinoma, diagnosis of invasive ductal pancreatic cancer compatible by computed tomography imaging, and followed-up until death or for 180 days or longer. The primary end point was overall survival, which was measured from the day of histological diagnosis. RESULTS: There were 440 patients who met the selection criteria. Of the 440 cases, 200 (45.5%) received curative resection (166 Stage I/II and 34 Stage III patients), 237 (53.9%) received chemotherapy (4 Stage I/II, 92 Stage III and 141 Stage IV patients), and the remaining 3 received palliative care. Univariate and multivariate regression analyses revealed that advanced computed tomography stage, high level of C-reactive protein (0.45 mg/dl or greater), neutrophil-lymphocyte ratio (2.0 or greater) and CA19-9 level (1000 U/ml or greater) were significantly associated with worse prognosis. CONCLUSIONS: We verified the results of previous studies, and showed that neutrophil-lymphocyte ratio and C-reactive protein also had prognostic value in a large Japanese PC cohort.


Assuntos
Proteína C-Reativa/metabolismo , Carcinoma Ductal Pancreático/sangue , Linfócitos , Neutrófilos , Neoplasias Pancreáticas/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Ductal Pancreático/patologia , Feminino , Humanos , Japão , Contagem de Linfócitos , Linfócitos/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neutrófilos/patologia , Neoplasias Pancreáticas/patologia , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos
19.
J Arthroplasty ; 30(5): 879-84, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25540995

RESUMO

We retrospectively analyzed 83 metal-on-metal total hip arthroplasties in 74 patients. Ultrasonography and magnetic resonance imaging (MRI) of each hip were performed to detect abnormal patterns and pseudotumors. We examined the reliability of ultrasonography for detecting pseudotumors in comparison with MRI. We also compared the acetabular component inclination between patients with and without pseudotumors. The mean positive and negative predictive values for pseudotumor detection by ultrasonography were 65% and 91%, respectively. The mean positive and negative likelihood ratios were 5.78 and 0.32, respectively. There was no clear association between pseudotumor presence and acetabular component inclination. We concluded that ultrasonography is a suitable technique to screen for the presence of pseudotumors. We also need to distinguish between bearing-related and taper junction corrosion-related complications.


Assuntos
Artroplastia de Quadril/efeitos adversos , Granuloma de Células Plasmáticas/diagnóstico por imagem , Prótese de Quadril , Próteses Articulares Metal-Metal/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Granuloma de Células Plasmáticas/diagnóstico , Granuloma de Células Plasmáticas/etiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Ultrassonografia
20.
J Stroke Cerebrovasc Dis ; 23(10): 2857-2861, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25280821

RESUMO

OBJECTIVE: The purpose of this study was to clarify the features of posterior inferior cerebellar artery (PICA) dissection. MATERIALS AND METHODS: We prospectively registered 93 consecutive patients and 108 arteries with confirmed diagnoses of dissection in the vertebral artery (VA) or PICA between February 2007 and January 2014. Patients were diagnosed with arterial dissection when they had both acute symptoms and radiological characteristics in magnetic resonance imaging or digital subtraction angiography. Patients were divided into 2 groups depending on whether the site of dissection was VA (VA group) or PICA (PICA group). We compared the clinical and radiological characteristics and clinical outcomes of PICA versus VA dissection. RESULTS: Of the 93 patients included in this study, 83 were in the VA group, and 10 had arterial dissection in the PICA. Patients with PICA dissection more frequently suffered from SAH (P < .001), whereas nonstroke symptom was often the initial symptom in the VA group. Pearl sign was seen most frequently at the dissection site of PICA. Surgical or endovascular treatment was performed in 9 of 10 PICA dissections, whereas more than half of the VA dissections were treated conservatively (P < .001). SAH was significantly more severe in the patients with PICA dissection compared with those in the VA group (P = .049). CONCLUSION: Patients with PICA dissection suffered from subarachnoid hemorrhage more frequently than those with VA dissection. PICA dissection was treated with surgical intervention, whereas VA dissection was treated conservatively.


Assuntos
Dissecção Aórtica/complicações , Dissecção Aórtica/diagnóstico , Cerebelo/irrigação sanguínea , Artérias Cerebrais , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/diagnóstico , Dissecação da Artéria Vertebral/complicações , Dissecação da Artéria Vertebral/diagnóstico , Adulto , Idoso , Dissecção Aórtica/terapia , Angiografia Digital , Angiografia Cerebral/métodos , Artérias Cerebrais/diagnóstico por imagem , Artérias Cerebrais/patologia , Artérias Cerebrais/cirurgia , Procedimentos Endovasculares , Feminino , Humanos , Aneurisma Intracraniano/terapia , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Prognóstico , Estudos Prospectivos , Fatores de Risco , Hemorragia Subaracnóidea/diagnóstico , Hemorragia Subaracnóidea/etiologia , Dissecação da Artéria Vertebral/terapia
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