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1.
Cancer Manag Res ; 16: 37-48, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38259607

RESUMO

Background: Colorectal cancer (CRC) is a common malignancy, especially among older adults. Inflammation has been implicated in cancer progression, making inflammatory indices potential prognostic markers. This study aimed to evaluate the prognostic significance of the Glasgow prognostic score (GPS), neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), lymphocyte/C-reactive protein ratio (LCR), and C-reactive protein/albumin ratio (CAR) in older adults with CRC. Methods: This population-based, retrospective observational study included patients aged ≥ 65 years with colorectal adenocarcinoma who were admitted to Taichung Veterans General Hospital (Chiayi branch) between 2017 and 2022. Demographic and clinicopathological characteristics, and results of inflammatory indices were collected from medical records for all patients. Receiver operating characteristic (ROC) curve analyses were performed to determine the optimal cutoffs of the inflammatory indices in predicting overall mortality. Associations between the inflammatory indices, overall survival (OS) and progression-free survival (PFS) were determined using univariate and multivariable Cox proportional hazard regression analyses, with model performance evaluated using the C-index. Results: Data of 106 patients were analyzed. After adjusting for confounders, GPS ≥1 (vs 0) significantly predicted poor OS (adjusted hazard ratio [aHR]: 3.80, 95% confidence interval [CI]: 1.30-11.10, p= 0.015, C-index= 0.825) and PFS (aHR: 3.19, 95% CI: 1.34-7.57, p= 0.008, C-index= 0.785). CAR ≥1.0 (vs <1) significantly predicted poor OS (aHR: 2.36, 95% CI: 1.01-5.48), p=0.046, C-index= 0.825) and PFS (aHR: 2.33, 95% CI: 1.14-4.76, p= 0.020, C-index= 0.786). Conclusion: Among hospitalized older adults with CRC in Taiwan, high GPS and CAR, but not NLR, PLR or LCR, are potentially useful prognostic indicators for poor OS and PFS.

2.
Int J Surg Case Rep ; 91: 106798, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35131626

RESUMO

INTRODUCTION AND IMPORTANCE: The most common symptoms of primary gastrointestinal (GI) lymphoma are non-specific, such as nausea, vomiting, diarrhea, weight loss, and abdominal pain. The rare acute symptoms include bowel obstruction, intussusception, and perforation. Primary small bowel lymphoma accounts for the smallest proportion of all GI malignancies. We report a case of intestinal lymphoma presenting with bloody stools and anemia. CASE PRESENTATION: The patient initially underwent both duodenoscopy and colonoscopy with negative findings. Isotopic red blood cell (RBC) scan was then performed due to persistent bleeding along with computed tomography angiography (CTA) because of suspected bleeding in the left abdomen. Successful embolization over the arcade of the sigmoid and left colic arteries was performed. However, the bleeding did not stop, and ischemic colitis was diagnosed by repeat colonoscopy. A coloenteric fistula was finally discovered during emergent laparotomy. CLINICAL DISCUSSION: GI lymphomas are a rare disease entity among the all GI malignancies. Despite acute abdominal symptoms including obstruction, perforation, bleeding and intussusception, enteral fistula is also one of the complications. It was seen to be a long-term complication after treatment or disease process in most of cases, however it could occur as the initial manifestation. GI bleeding is a life-threatening condition and commonly needs prompt decision making. There were no standard managements for these patients, it depends on clinical judgements from physician individually. CONCLUSION: This is a rare condition that has not been previously described in Taiwan. Early diagnosis and timely management will decrease morbidity and mortality in the GI lymphoma population.

3.
Quant Imaging Med Surg ; 12(1): 43-52, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34993059

RESUMO

BACKGROUND: Ischemia before the development of dysbaric osteonecrosis (DON) in femoral heads has never been investigated. We assessed whether quantitative magnetic resonance spectroscopy (MRS) and diffusion weighted imaging (DWI) could detect dysbaric changes in divers with hip pain. METHODS: This IRB-approved exploratory study recruited 17 divers [9 with hip pain (Group 1); 8 asymptomatic (Group 2)] with normal findings on radiographs and conventional magnetic resonance imaging scans were age-, gender- and body-mass-index matched to 17 non-divers as controls (Group 1C, 2C). Apparent diffusion coefficients (ADCs) and MRS spectra were obtained from regions/voxels of interest on the femoral heads of all subjects. LCModel was used to determine water content, lipid composition, and the unsaturation index in bone marrow. Mann-Whitney non-parametric test was used to compare results of quantitative MRS and ADCs of ipsilateral femoral heads between divers and controls. RESULTS: MRS of the ipsilateral femoral heads revealed higher water (peak: 4.7 ppm) content, lower total lipid fraction (TLF), and higher unsaturation index (UI) of lipids in Group 1 than in Group 2 (water: P=0.040; UI: P=0.022) and Group 1C (water: P=0.027; TLF: P=0.039; UI: P=0.009). In contrast, femoral head ADCs were comparable between divers and controls. Five out of nine symptomatic divers were contacted for follow-up MRS and DWI studies, and the mean difference in water content in the femoral heads of patients with osteonecrosis was also higher than that in patients with symptom relief (osteonecrosis: 0.077±0.130 vs. symptom relief: 0.003±0.010). CONCLUSIONS: Dysbaric change in the femoral heads of divers with hip pain can be detected using quantitative MRS, which reveals increases in water content and UI of lipids, and a decrease in TLF.

4.
Sci Rep ; 11(1): 9924, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976243

RESUMO

The purpose of present study was to longitudinally investigate the alterations in infrapatellar fat pad (IPFP) vascularity in 5/6 nephrectomized rats by using dynamic contrast enhanced (DCE) MRI and IPFP degeneration by using MRI T2* relaxation time. Twelve male Sprague-Dawley rats were assigned to a control group and a 5/6 nephrectomy CKD group. The right knees of all rats were longitudinally scanned by 4.7 T MRI, and serial changes in the IPFP were assessed at 0, 8, 16, 30, and 44 weeks by DCE-MRI (parameters A, kel and kep) and MRI T2* mapping. After MRI measurements, knee specimens were obtained and evaluated histologically. The CKD group had IPFPs with lower blood volume A and lower permeability kep values from 16 weeks (p < 0.05), lower venous washout kel value from 30 weeks (p < 0.001), and significantly higher T2* values reflecting adipocyte degeneration beginning at 16 weeks (p < 0.05). The histopathological results confirmed the MRI findings. Hypoperfusion and adipocytes degeneration related to CKD were demonstrated in a rodent 5/6 nephrectomy model. DCE parameters and MRI T2* can serve as imaging biomarkers of fat pad degeneration during CKD progression.


Assuntos
Tecido Adiposo/patologia , Rim/patologia , Articulação do Joelho/patologia , Insuficiência Renal Crônica/patologia , Tecido Adiposo/irrigação sanguínea , Animais , Progressão da Doença , Articulação do Joelho/irrigação sanguínea , Imageamento por Ressonância Magnética , Masculino , Nefrectomia , Ratos , Ratos Sprague-Dawley , Insuficiência Renal Crônica/etiologia
5.
Eur Radiol ; 28(11): 4504-4513, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29736847

RESUMO

OBJECTIVES: To compare diffusion tensor (DT)-derived indices from the thalamic nuclei and cerebrospinal fluid (CSF) hydrodynamic parameters for the prediction of gait responsiveness to the CSF tap test in early iNPH patients. METHODS: In this study, 22 patients with iNPH and 16 normal controls were enrolled with the approval of an institutional review board. DT imaging and phase-contrast magnetic resonance imaging were performed in patients and controls to determine DT-related indices of the sensorimotor-related thalamic nuclei and CSF hydrodynamics. Gait performance was assessed in patients using gait scale before and after the tap test. The Mann-Whitney U test and receiver operating characteristic (ROC) curve analysis were applied to compare group differences between patients and controls and assess the predictive performance of gait responsiveness to the tap test in the patients. RESULTS: Fractional anisotropy (FA) and axial diffusivity showed significant increases in the ventrolateral (VL) and ventroposterolateral (VPL) nuclei of the iNPH group compared with those of the control group (p < 0.05). The predictions of gait responsiveness of ventral thalamic FA alone (area under the ROC curve [AUC] < 0.8) significantly outperformed those of CSF hydrodynamics alone (AUC < 0.6). The AUC curve was elevated to 0.812 when the CSF peak systolic velocity and FA value were combined for the VPL nucleus, yielding the highest sensitivity (0.769) and specificity (0.778) to predict gait responses. CONCLUSIONS: Combined measurements of sensorimotor-related thalamic FA and CSF hydrodynamics can provide potential biomarkers for gait response to the CSF tap test in patients with iNPH. KEY POINTS: • Ventrolateral and ventroposterolateral thalamic FA may predict gait responsiveness to tap test. • Thalamic neuroplasticity can be assessed through DTI in idiopathic normal-pressure hydrocephalus. • Changes in the CST associated with gait control could trigger thalamic neuroplasticity. • Activities of sensorimotor-related circuits could alter in patients with gait disturbance. • Management of patients with iNPH could be more appropriate.


Assuntos
Líquido Cefalorraquidiano/fisiologia , Marcha/fisiologia , Hidrocefalia de Pressão Normal/fisiopatologia , Tálamo/fisiologia , Idoso , Anisotropia , Estudos de Casos e Controles , Imagem de Difusão por Ressonância Magnética , Imagem de Tensor de Difusão , Feminino , Humanos , Hidrodinâmica , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Curva ROC , Sensibilidade e Especificidade
6.
Comput Methods Programs Biomed ; 155: 19-27, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29512499

RESUMO

BACKGROUND AND OBJECTIVE: To investigate the feasibility of histogram analysis of the T2*-based permeability parameter volume transfer constant (Ktrans) for glioma grading and to explore the diagnostic performance of the histogram analysis of Ktrans and blood plasma volume (vp). METHODS: We recruited 31 and 11 patients with high- and low-grade gliomas, respectively. The histogram parameters of Ktrans and vp, derived from the first-pass pharmacokinetic modeling based on the T2* dynamic susceptibility-weighted contrast-enhanced perfusion-weighted magnetic resonance imaging (T2* DSC-PW-MRI) from the entire tumor volume, were evaluated for differentiating glioma grades. RESULTS: Histogram parameters of Ktrans and vp showed significant differences between high- and low-grade gliomas and exhibited significant correlations with tumor grades. The mean Ktrans derived from the T2* DSC-PW-MRI had the highest sensitivity and specificity for differentiating high-grade gliomas from low-grade gliomas compared with other histogram parameters of Ktrans and vp. CONCLUSIONS: Histogram analysis of T2*-based pharmacokinetic imaging is useful for cerebral glioma grading. The histogram parameters of the entire tumor Ktrans measurement can provide increased accuracy with additional information regarding microvascular permeability changes for identifying high-grade brain tumors.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Meios de Contraste/farmacocinética , Glioma/diagnóstico por imagem , Glioma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Barreira Hematoencefálica , Neoplasias Encefálicas/irrigação sanguínea , Permeabilidade Capilar , Feminino , Glioma/irrigação sanguínea , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Neovascularização Patológica , Estudos Retrospectivos , Sensibilidade e Especificidade
7.
Sci Rep ; 7(1): 3073, 2017 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-28596576

RESUMO

The pathogenesis of chronic kidney disease (CKD) is multifactorial. In the progression of CKD arthropathy, arteriosclerosis may alter the knee subchondral bone marrow by altering blood flow through the bone vasculature. Herein, multi-parametric MRI assessment, including dynamic contrast enhanced magnetic resonance imaging (DCE-MRI), magnetic resonance spectroscopy (MRS), MRI T2*, contrast enhanced MR angiography (CE-MRA), and micro-CT were applied in a rodent nephrectomy model to: 1) investigate the blood perfusion of subchondral bone marrow and its relationship to fat water content and trabeculation pattern in CKD and 2) demonstrate the feasibility of using multi-parametric MRI parameters as imaging biomarkers to evaluate the disease's progression. Two groups of rats in our study underwent either 1) no intervention or 2) 5/6 nephrectomy. We found that in the CKD group, perfusion amplitude A and elimination constant k el values were significantly decreased, and vascular permeability k ep was significantly increased. MRS showed that fat fraction (FF) was significantly lower, water fraction (WF) was significantly higher in the CKD group. Micro-CT showed a significant loss of trabecular bone. Knee subchondral bone marrow perfusion deficiency in experimental CKD may be associated with decreased fat content, increased water content, and sparse trabeculation.


Assuntos
Medula Óssea/patologia , Osso e Ossos/irrigação sanguínea , Artropatias/diagnóstico , Artropatias/etiologia , Imageamento por Ressonância Magnética , Insuficiência Renal Crônica/complicações , Microtomografia por Raio-X , Animais , Medula Óssea/diagnóstico por imagem , Osso e Ossos/diagnóstico por imagem , Modelos Animais de Doenças , Imuno-Histoquímica , Imageamento por Ressonância Magnética/métodos , Masculino , Ratos , Microtomografia por Raio-X/métodos
8.
Medicine (Baltimore) ; 96(5): e5982, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28151889

RESUMO

Evaluation of acute white matter injuries caused by carbon monoxide (CO) poisoning can be limited by conventional magnetic resonance (MR) imaging. We aim to evaluate the feasibility of diffusion kurtosis imaging (DKI) for early detection of white matter alterations in patients with acute CO intoxication.A total of 30 subjects including 15 acute CO patients and 15 age- and sex-matched healthy volunteers were enrolled in this study. MR examinations were performed on a 3T MR scanner within 8 days after CO intoxication. DKI data were acquired to derive axial, radial, and mean kurtosis, as well as fractional anisotropy (FA), axial, radial, and mean diffusivity for tract-specific comparisons between the 2 groups.Significant decreases of mean kurtosis were shown in the genu of corpus callosum, cingulum, and motor-related tracts (corticospinal and corticobulbar tracts) in patients with acute CO intoxication as compared with controls. On the contrary, significant differences of FA values were merely shown in the regions of corticospinal tracts.DKI demonstrated comparably stronger potential than diffusion tensor imaging in terms of early detection of white matter changes in patients with acute CO intoxication. This may have implications in therapeutic strategy for managing acute CO intoxication patients.


Assuntos
Intoxicação por Monóxido de Carbono/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Substância Branca/diagnóstico por imagem , Adulto , Anisotropia , Intoxicação por Monóxido de Carbono/complicações , Estudos de Casos e Controles , Corpo Caloso/diagnóstico por imagem , Estudos de Viabilidade , Feminino , Giro do Cíngulo/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Motor/diagnóstico por imagem , Substância Branca/lesões
9.
Medicine (Baltimore) ; 95(19): e3636, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27175677

RESUMO

In this study, we aimed to investigate the reactive changes in diffusion tensor imaging (DTI)-derived diffusion metrics of the anterior thalamic nucleus (AN), a relaying center for the Papez circuit, in early idiopathic normal pressure hydrocephalus (iNPH) patients with memory impairment, as well as its correlation with the patients' neuropsychological performances. In total, 28 probable iNPH patients with symptom onset within 1 year and 17 control subjects were prospectively recruited between 2010 and 2013 for this institutional review board-approved study. Imaging studies including DTI and a neuropsychological assessment battery were performed in all subjects. Diffusion metrics were measured from the region of the AN using tract-deterministic seeding method by reconstructing the mammillo-thalamo-cingulate connections within the Papez circuit. Differences in diffusion metrics and memory assessment scores between the patient and control group were examined via the Mann-Whitney U test. Spearman correlation analyses were performed to examine associations between diffusion metrics of AN and neuropsychological tests within the patient group. We discovered that early iNPH patients exhibited marked elevations in fractional anisotropy, pure diffusion anisotropy, and axial diffusivity (all P < 0.01), as well as lower neuropsychological test scores including verbal and nonverbal memory (all P < 0.05) compared with normal control. Spearman rank correlation analyses did not disclose significant correlations between AN diffusion metrics and neuropsychological test scores in the patient group, whereas ranked scatter plots clearly demonstrated a dichotic sample distribution between patient and control samples. In summary, our study highlighted the potential compensatory role of the AN by increasing thalamocortical connectivity within the Papez circuit because memory function declines in early iNPH when early shunt treatment may potentially reverse the memory deficits.


Assuntos
Núcleos Anteriores do Tálamo/fisiopatologia , Hidrocefalia de Pressão Normal/fisiopatologia , Transtornos da Memória/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Anisotropia , Núcleos Anteriores do Tálamo/diagnóstico por imagem , Estudos de Casos e Controles , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Hidrocefalia de Pressão Normal/complicações , Hidrocefalia de Pressão Normal/psicologia , Masculino , Transtornos da Memória/etiologia , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estudos Prospectivos
10.
Medicine (Baltimore) ; 94(50): e2311, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26683969

RESUMO

Calcification of the middle cerebral artery (MCA) is uncommon in the healthy elderly. Whether calcification of the MCA is associated with cerebral ischemic stroke remains undetermined. We intended to investigate the association using Agatston calcium scoring of the MCA. This study retrospectively included 354 subjects with ischemic stroke in the MCA territory and 1518 control subjects who underwent computed tomography (CT) of the brain. We recorded major known risk factors for ischemic stroke, including age, gender, hypertension, diabetes mellitus, smoking, hyperlipidemia, and obesity, along with the MCA calcium burden, measured with the Agatston calcium scoring method. Univariate and modified logistic regression analyses were performed to examine the association between the MCA calcification and ischemic stroke. The univariate analyses showed significant associations of ischemic stroke with age, hypertension, diabetes mellitus, smoking, total MCA Agatston score, and the presence of calcification on both or either side of the MCA. Subjects with the presence of MCA calcification on both or either side of the MCA were 8.46 times (95% confidence interval, 4.93-14.53; P < 0.001) more likely to have a cerebral infarct than subjects without MCA calcification after adjustment for the major known risk factors, including age, hypertension, diabetes mellitus, and smoking. However, a higher degree of MCA calcification reflected by the Agatston score was not associated with higher risk of MCA ischemic stroke after adjustment for the confounding factors and presence of MCA calcification. These results suggest that MCA calcification is associated with ischemic stroke in the MCA territory. Further prospective studies are required to verify the clinical implications of the MCA calcification.


Assuntos
Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/diagnóstico , Calcificação Vascular/complicações , Calcificação Vascular/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X
11.
Medicine (Baltimore) ; 94(39): e1546, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26426620

RESUMO

The effect of intracranial internal carotid artery (ICA) calcification on cognitive impairment is uncertain. Our objective was to investigate whether intracranial ICA calcification is a significant cognitive predictor for cognitive impairment. Global cognition and degrees of intracranial ICA calcification of 579 subjects were assessed with Mini-Mental State Examination (MMSE) and Agatston calcium scoring method, respectively. Other risk factors for cognitive impairment, including age, education level, hypertension, diabetes mellitus, smoking, hyperlipidemia, and body mass index, were documented and analyzed for their associations with cognitive function. In univariate analyses, older age, lower education level, hypertension, diabetes mellitus, and higher intracranial ICA Agatston scores were significantly associated with cognitive impairment. In ordinal logistic regression, only age and total intracranial ICA Agatston score were significant risk factors for cognitive impairment. After adjustment for the other documented risk factors, subjects were 7% (95% CI: 5-10; P < 0.001) and 6% (95% CI: 0-13; P = 0.04) more likely to have lower cognitive category with every year increment of age and every 100-point increment of the total intracranial ICA Agatston score respectively. These results suggest an important role of the intracranial ICA calcification on cognitive impairment.


Assuntos
Calcinose/complicações , Doenças das Artérias Carótidas/complicações , Artéria Carótida Interna , Transtornos Cognitivos/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Índice de Gravidade de Doença
12.
J Orthop Res ; 33(9): 1348-55, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25940708

RESUMO

The Hoffa fat pad (infrapatellar fat pad) is a source of post-traumatic anterior knee pain, and Hoffa disease is a syndrome leading to chronic inflammation of the fat pad. Herein, change in T2* relaxation time of the fat pad was measured in a rodent anterior cruciate ligament transection (ACLX) model in order to (i) examine the causal relationship of anterior cruciate ligament (ACL) deficiency and Hoffa disease and (ii) demonstrate the feasibility of using T2* as an imaging biomarker to monitor disease progression. Three groups of male Sprague Dawley rats (n = 6 each group), received either (i) no intervention; (ii) sham surgery at the right knee; or (iii) right ACLX. T2* relaxation time was measured and histology was examined in the Hoffa fat pad after surgery. At 13 and 18 weeks after surgery, T2* values were significantly higher in the right fat pad than the left (p < 0.001) and significantly higher in the ACLX group than the control and sham groups (p < 0.001). Histology showed fibrosis and degeneration of adipocytes in the right knees of the ACLX group. We conclude that ACL deficiency and Hoffa disease are causally related and that MRI T2* value can serve as an imaging biomarker of Hoffa disease progression.


Assuntos
Tecido Adiposo/patologia , Ligamento Cruzado Anterior/cirurgia , Adipócitos/citologia , Animais , Progressão da Doença , Processamento de Imagem Assistida por Computador , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
13.
Biomed Res Int ; 2013: 970586, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23862163

RESUMO

Recent advances in the treatment of cerebral gliomas have increased the demands on noninvasive neuroimaging for the diagnosis, therapeutic planning, tumor monitoring, and patient outcome prediction. In the meantime, improved magnetic resonance (MR) imaging techniques have shown much potentials in evaluating the key pathological features of the gliomas, including cellularity, invasiveness, mitotic activity, angiogenesis, and necrosis, hence, further shedding light on glioma grading before treatment. In this paper, an update of advanced MR imaging techniques is reviewed, and their potential roles as biomarkers of tumor grading are discussed.


Assuntos
Neoplasias Encefálicas/diagnóstico , Glioma/diagnóstico , Imageamento por Ressonância Magnética , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/patologia , Glioma/irrigação sanguínea , Glioma/patologia , Humanos , Mitose , Invasividade Neoplásica , Neovascularização Patológica/diagnóstico
14.
Stroke ; 44(7): 1872-7, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23743977

RESUMO

BACKGROUND AND PURPOSE: Brain enhancement on contrast-enhanced T1-weighted imaging (CET1-WI) after ischemic stroke is generally accepted as an indicator of the blood-brain barrier disruption. However, this phenomenon usually starts to become visible at the subacute phase. The purpose of this study was to evaluate the time-course profiles of K(trans), cerebral blood volume (vp), and CET1-WI with early detection of blood-brain barrier changes on K(trans) maps and their role for prediction of subsequent hemorrhagic transformation in acute middle cerebral arterial infarct. METHODS: Twenty-six patients with acute middle cerebral arterial stroke and early spontaneous reperfusion, whose MR images were obtained at predetermined stroke stages, were included. T2*-based MR perfusion-weighted images were acquired using the first-pass pharmacokinetic model to derive K(trans) and vp. Parenchymal enhancement observed on maps of K(trans), vp, and CET1-WI at each stage was compared. Association among these measurements and hemorrhagic transformation was analyzed. RESULTS: K(trans) map showed significantly higher parenchymal enhancement in ischemic parenchyma as compared with that of vp map and CET1-WI at early stroke stages (P<0.05). The increased K(trans) at acute stage was not associated with parenchymal enhancement in CET1-WI at the same stage. Parenchymal enhancement in CET1-WI started to occur at the late subacute stage and tended to be luxury reperfusion-dependent. Patients with hemorrhagic transformation showed higher mean K(trans) values as compared with patients without hemorrhagic transformation (P=0.02). CONCLUSIONS: Postischemic brain enhancement on routine CET1-WI seems to be closely related to the luxury reperfusion at the late subacute stage and is not dependent on microvascular permeability changes at the acute stage.


Assuntos
Isquemia Encefálica/diagnóstico , Permeabilidade Capilar/fisiologia , Hemorragia Cerebral/diagnóstico , Imagem de Difusão por Ressonância Magnética/métodos , Aumento da Imagem/métodos , Acidente Vascular Cerebral/diagnóstico , Doença Aguda , Adulto , Doença Crônica , Imagem de Difusão por Ressonância Magnética/instrumentação , Seguimentos , Humanos , Aumento da Imagem/instrumentação , Infarto da Artéria Cerebral Média
15.
PLoS One ; 8(3): e59769, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23555775

RESUMO

PURPOSE: The magnetic resonance (MR) T2 value of cartilage is a reliable indicator of tissue properties and therefore may be used as an objective diagnostic tool in early meniscal degeneration. The purpose of this study was to investigate age, gender, location, and zonal differences in MR T2 value of the posterior horns of knee menisci in asymptomatic subjects. METHODS: Sixty asymptomatic volunteers (30 men and 30 women) were enrolled and divided into three different age groups: 20-34, 35-49 and 50-70 years. The inclusion criteria were BMI<30 kg/cm(2), normalized Western Ontario and McMaster Universities (WOMAC) pain score of zero, and no evidence of meniscal and ligamentous abnormalities on routine knee MR imaging. The T2 values were measured on images acquired with a T2-weighted fat-suppressed turbo spin-echo sequence at 3T. RESULTS: The mean T2 values in both medial and lateral menisci for the 20-34, 35-49, and 50-70 age groups were 9.94 msec±0.94, 10.73 msec±1.55, and 12.36 msec±2.27, respectively, for women and 9.17 msec±0.74, 9.64 msec±0.67, and 10.95 msec±1.33, respectively, for men. The T2 values were significantly higher in the 50-70 age group than the 20-34 age group (P<0.001) and in women than in men (P = 0.001, 0.004, and 0.049 for each respective age group). T2 values were significantly higher in medial menisci than in lateral menisci only in women age 50-70 (3.33 msec, P = 0.006) and in the white zone and red/white zone of the 50-70 and 35-49 age groups than that of the 20-34 age group (2.47, 1.02; 2.77, 1.16 msec, respectively, all P<0.01). CONCLUSION: The MR T2 values of the posterior meniscal horns increase with increasing age in women and are higher in women than in men. The age-related rise of T2 values appears to be more severe in medial menisci than in lateral menisci. Differences exist in the white zone and red/white zone.


Assuntos
Cartilagem Articular/patologia , Joelho/patologia , Imageamento por Ressonância Magnética , Meniscos Tibiais/patologia , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/patologia , Adulto Jovem
16.
Radiology ; 265(1): 215-21, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22829682

RESUMO

PURPOSE: To quantitatively investigate signal alterations of the substantia nigra in patients with delayed parkinsonism following CO intoxication, as seen on gray matter (GM)-suppressed inversion-recovery (IR) magnetic resonance (MR) images. MATERIALS AND METHODS: This prospective study was approved by the local institutional review board, and written informed consent was obtained from all subjects. Thirteen patients with delayed onset of CO-induced parkinsonism (nine men and four women; mean age, 40.3 years), 13 age-matched CO-intoxicated patients without parkinsonism, and 13 age-matched healthy volunteers were examined with GM-suppressed IR MR imaging. The signal intensity of the substantia nigra was normalized to the adjacent normal-appearing white matter in the temporal lobe, followed by semiautomatic segmentation into medial, middle, and lateral parts by using a skeleton-based algorithm. Multivariate and univariate analyses and Spearman rank correlation test were performed to examine the relationships between variables. Clinical severity was assessed with the modified Hoehn and Yahr rating scale. RESULTS: The normalized signal ratios in the middle and lateral segments of the substantia nigra were significantly higher in those with CO-induced parkinsonism, compared with those with CO intoxication without parkinsonism or normal volunteers (P=.02). For the medial segments, the ratios showed no significant differences among the groups. The normalized signal ratios of substantia nigra were correlated with the severity of parkinsonism, particularly in the lateral segments (ρ=0.927, P<.001). CONCLUSION: CO toxicity to the substantia nigra plays a role in pathophysiologic mechanisms of CO-induced parkinsonism. GM-suppressed IR MR imaging is a useful tool in depicting substantia nigra injury following CO intoxication.


Assuntos
Intoxicação por Monóxido de Carbono/complicações , Imageamento por Ressonância Magnética/métodos , Transtornos Parkinsonianos/etiologia , Transtornos Parkinsonianos/patologia , Substância Negra/patologia , Adulto , Análise de Variância , Estudos de Casos e Controles , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Estudos Prospectivos , Índice de Gravidade de Doença , Estatísticas não Paramétricas
17.
Radiology ; 260(2): 531-40, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21633053

RESUMO

PURPOSE: To investigate the effects of 3,4-methylenedioxymethamphetamine (MDMA, commonly known as "ecstasy") on the alterations of brain metabolites and anatomic tissue integrity related to the function of the basal ganglia-thalamocortical circuit by using proton magnetic resonance (MR) spectroscopy and diffusion-tensor MR imaging. MATERIALS AND METHODS: This study was approved by a local institutional review board, and written informed consent was obtained from all subjects. Thirty-one long-term (>1 year) MDMA users and 33 healthy subjects were enrolled. Proton MR spectroscopy from the middle frontal cortex and bilateral basal ganglia and whole-brain diffusion-tensor MR imaging were performed with a 3.0-T system. Absolute concentrations of metabolites were computed, and diffusion-tensor data were registered to the International Consortium for Brain Mapping template to facilitate voxel-based group comparison. RESULTS: The mean myo-inositol level in the basal ganglia of MDMA users (left: 4.55 mmol/L ± 2.01 [standard deviation], right: 4.48 mmol/L ± 1.33) was significantly higher than that in control subjects (left: 3.25 mmol/L ± 1.30, right: 3.31 mmol/L ± 1.19) (P < .001). Cumulative lifetime MDMA dose showed a positive correlation with the levels of choline-containing compounds (Cho) in the right basal ganglia (r = 0.47, P = .02). MDMA users also showed a significant increase in fractional anisotropy (FA) in the bilateral thalami and significant changes in water diffusion in several regions related to the basal ganglia-thalamocortical circuit as compared with control subjects (P < .05; cluster size, >50 voxels). CONCLUSION: Increased myo-inositol and Cho concentrations in the basal ganglia of MDMA users are suggestive of glial response to degenerating serotonergic functions. The abnormal metabolic changes in the basal ganglia may consequently affect the inhibitory effect of the basal ganglia to the thalamus, as suggested by the increased FA in the thalamus and abnormal changes in water diffusion in the corresponding basal ganglia-thalamocortical circuit.


Assuntos
Gânglios da Base/efeitos dos fármacos , Mapeamento Encefálico/métodos , Córtex Cerebral/efeitos dos fármacos , Imagem de Tensor de Difusão/métodos , Espectroscopia de Ressonância Magnética/métodos , N-Metil-3,4-Metilenodioxianfetamina/toxicidade , Tálamo/efeitos dos fármacos , Adolescente , Adulto , Anisotropia , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Gânglios da Base/fisiopatologia , Córtex Cerebral/fisiopatologia , Colina/metabolismo , Creatina/metabolismo , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Inositol/metabolismo , Masculino , Fosfocreatina/metabolismo , Estatísticas não Paramétricas , Tálamo/fisiopatologia
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