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1.
Neuroimage ; 300: 120859, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39317274

RESUMO

BACKGROUND: The pathophysiology of protracted symptoms after COVID-19 is unclear. This study aimed to determine if long-COVID is associated with differences in baseline characteristics, markers of white matter diffusivity in the brain, and lower scores on objective cognitive testing. METHODS: Individuals who experienced COVID-19 symptoms for more than 60 days post-infection (long-COVID) (n = 56) were compared to individuals who recovered from COVID-19 within 60 days of infection (normal recovery) (n = 35). Information regarding physical and mental health, and COVID-19 illness was collected. The National Institute of Health Toolbox Cognition Battery was administered. Participants underwent magnetic resonance imaging (MRI) with diffusion tensor imaging (DTI). Tract-based spatial statistics were used to perform a whole-brain voxel-wise analysis on standard DTI metrics (fractional anisotropy, axial diffusivity, mean diffusivity, radial diffusivity), controlling for age and sex. NIH Toolbox Age-Adjusted Fluid Cognition Scores were used to compare long-COVID and normal recovery groups, covarying for Age-Adjusted Crystallized Cognition Scores and years of education. False discovery rate correction was applied for multiple comparisons. RESULTS: There were no significant differences in age, sex, or history of neurovascular risk factors between the groups. The long-COVID group had significantly (p < 0.05) lower mean diffusivity than the normal recovery group across multiple white matter regions, including the internal capsule, anterior and superior corona radiata, corpus callosum, superior fronto-occiptal fasciculus, and posterior thalamic radiation. However, the effect sizes of these differences were small (all ß<|0.3|) and no significant differences were found for the other DTI metrics. Fluid cognition composite scores did not differ significantly between the long-COVID and normal recovery groups (p > 0.05). CONCLUSIONS: Differences in diffusivity between long-COVID and normal recovery groups were found on only one DTI metric. This could represent subtle areas of pathology such as gliosis or edema, but the small effect sizes and non-specific nature of the diffusion indices make pathological inference difficult. Although long-COVID patients reported many neuropsychiatric symptoms, significant differences in objective cognitive performance were not found.


Assuntos
Encéfalo , COVID-19 , Cognição , Imagem de Tensor de Difusão , Humanos , COVID-19/patologia , COVID-19/diagnóstico por imagem , Masculino , Feminino , Imagem de Tensor de Difusão/métodos , Adulto , Pessoa de Meia-Idade , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Cognição/fisiologia , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , SARS-CoV-2 , Testes Neuropsicológicos , Idoso , Síndrome de COVID-19 Pós-Aguda , Imageamento por Ressonância Magnética/métodos
2.
J Clin Gastroenterol ; 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37646564

RESUMO

INTRODUCTION: The serum-based endoscopic healing index (EHI) test identifies endoscopic Crohn's disease (CD) activity. Data are lacking on the relationship between EHI with other endpoints. We assessed the relationship between EHI and the simplified Magnetic Resonance Index of Activity. MATERIALS AND METHODS: Data were prospectively collected on patients with CD with either an EHI or fecal calprotectin (FCAL) within 90 days of magnetic resonance enterography (MRE). Diagnostic accuracy was assessed using area under the receiver operator characteristics. Proportions with any, severe, and terminal ileum MR inflammation were compared above/below identified thresholds for both EHI and FCAL. RESULTS: A total of 241 MREs paired to either EHI or FCAL from 155 patients were included. Both EHI and FCAL had similar accuracy to diagnose inflammation (area under the receiver operator characteristics: EHI: 0.635 to 0.651, FCAL: 0.680 to 0.708). Optimal EHI values were 42 and 26 for inflammation on MRE and endoscopy, respectively. Patients with EHI ≥42 (100% vs. 63%, P=0.002), FCAL >50 µg/g (87% vs. 64%, P<0.001) and FCAL >250 µg/g (90% vs. 75%, P=0.02) had higher rates of simplified Magnetic Resonance Index of Activity ≥1 compared with lower values. EHI differentiated ileitis numerically more than FCAL (delta: 24% to 25% vs. 11% to 21%). Patients with FCAL ≥50 µg/g had higher rates of severe inflammation compared with FCAL <50 µg/g (75% vs. 47%, P<0.001), whereas smaller differentiation existed for EHI threshold of 42 (63% vs. 49%, P=0.35). CONCLUSION: Both EHI and FCAL were specific in their confirmation of inflammation and disease activity on MRE in patients with CD. However, MRE-detected inflammation was frequently present in the presence of low EHI and FCAL in similar proportions.

3.
J Ultrasound Med ; 42(8): 1675-1688, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36744595

RESUMO

PURPOSE: To assess diagnostic performance of quantitative ultrasound (QUS) biomarkers in assessing hepatic steatosis. METHODS: We prospectively recruited 125 participants (mean age 54 years) who underwent liver QUS, magnetic resonance imaging (MRI), and laboratory tests within 30 days in this IRB approved study. Based on MRI-proton density fat fraction (MRI-PDFF) and MRE, we divided 125 participants into normal liver, nonalcoholic fatty liver (NAFL) and liver fibrosis (≥F1) groups. We examined diagnostic performance of ultrasound attenuation coefficient (AC), normalized local variance (NLV), superb microvascular imaging-based vascularity index (SMI-VI), and shear wave velocity (SWV) for determining hepatic steatosis and fibrosis using area under receiver operating characteristic curve (AUC). We also analyzed correlations of QUS biomarkers to MRI using Spearman correlation coefficient. RESULTS: We observed significant differences in AC, NLV, and SMI-VI among the three groups (22 participants with normal liver, 78 with NAFL, and 25 with liver fibrosis). AUC of AC, NLV, and SMI-VI for determining ≥ mild steatotic livers (MRI-PDFF ≥5%) was 0.95, 0.90, and 0.92, respectively. AUC of SWV for determining ≥ F1 liver fibrosis was 0.93. The correlation of MRI-PDFF was positive to AC (r = 0.91) and negative to NLV (r = -0.74), SMI-VI (r = -0.8) in NAFL group. There was a significant difference in regression slope of AC to MRI-PDFF in livers with and without ≥F1 (0.84 vs 0.91, P = .02). CONCLUSIONS: QUS biomarkers have high sensitivity and specificity to determine and grade hepatic steatosis and detect liver fibrosis. The effect of liver fibrosis on the performance of QUS biomarkers in quantifying liver fat content warrants further investigation.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/patologia , Estudos Prospectivos , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Biomarcadores , Imageamento por Ressonância Magnética/métodos
4.
J Magn Reson Imaging ; 54(5): 1466-1473, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33970516

RESUMO

BACKGROUND: While Prostate Imaging Reporting and Data System (PI-RADS) 4 and 5 lesions typically warrant prostate biopsy and PI-RADS 1 and 2 lesions may be safely observed, PI-RADS 3 lesions are equivocal. PURPOSE: To construct and cross-validate a machine learning model based on radiomics features from T2 -weighted imaging (T2 WI) of PI-RADS 3 lesions to identify clinically significant prostate cancer (csPCa), that is, pathological Grade Group ≥ 2. STUDY TYPE: Single-center retrospective study. POPULATION: A total of 240 patients were included (training cohort, n = 188, age range 43-82 years; test cohort, n = 52, age range 41-79 years). Eligibility criteria were 1) magnetic resonance imaging (MRI)-targeted biopsy between 2015 and 2020; 2) PI-RADS 3 index lesion identified on multiparametric MRI; (3) biopsy performed within 1 year of MRI. The percentages of csPCa lesions were 10.6% and 15.4% in the training and test cohorts, respectively. FIELD STRENGTH/SEQUENCE: A 3 T; T2 WI turbo-spin echo, diffusion-weighted spin-echo echo planar imaging, dynamic contrast-enhanced MRI with time-resolved T1-weighted imaging. ASSESSMENT: Multislice volumes-of-interest (VOIs) were drawn in the PI-RADS 3 index lesions on T2 WI. A total of 107 radiomics features (first-order histogram and second-order texture) were extracted from the segmented lesions. STATISTICAL TESTS: A random forest classifier using the radiomics features as input was trained and validated for prediction of csPCa. The performance of the machine learning classifier, prostate specific antigen (PSA) density, and prostate volume for csPCa prediction was evaluated using receiver operating characteristic (ROC) analysis. RESULTS: The trained random forest classifier constructed from the T2 WI radiomics features good and statistically significant area-under-the-curves (AUCs) of 0.76 (P = 0.022) for prediction of csPCa in the test set. Prostate volume and PSA density showed moderate and nonsignificant performance (AUC 0.62, P = 0.275 and 0.61, P = 0.348, respectively) for csPCa prediction in the test set. CONCLUSION: The machine learning classifier based on T2 WI radiomic features demonstrated good performance for prediction of csPCa in PI-RADS 3 lesions. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: 2.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Aprendizado de Máquina , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/diagnóstico por imagem , Estudos Retrospectivos
5.
Radiographics ; 40(2): 432-453, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32125951

RESUMO

Surgical mesh is used most frequently for tension-free repair of abdominal wall hernias in adults, because the rate of hernia recurrence is lower with mesh than with primary soft-tissue repair. Since the introduction of polypropylene mesh in the middle of the 20th century, many mesh materials and configurations for specific surgical procedures have been developed. In addition to abdominal wall hernia repair, mesh may be used for repair of diaphragmatic hernias, urinary incontinence in women (female slings), genitourinary prolapse (vaginal mesh and sacrocolpopexy), rectal prolapse (rectopexy), and postprostatectomy male urinary incontinence (male slings). General mesh repair complications include chronic pain; fluid collections such as seromas, hematomas, and abscesses; adhesions that may lead to intestinal blockage; erosion into solid or hollow viscera including enterocutaneous fistulizing disease; and mesh failure characterized by mesh shrinkage, detachment, and migration with repair malfunction. Several mesh complications are often diagnosed with imaging, primarily with CT and less frequently with MRI and US, despite variable mesh visibility at imaging. This article reviews the common surgical mesh applications in the abdomen and pelvis, discusses imaging of mesh repair complications, and provides complication treatment highlights.©RSNA, 2020.


Assuntos
Herniorrafia/métodos , Prolapso de Órgão Pélvico/cirurgia , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/terapia , Telas Cirúrgicas , Incontinência Urinária/cirurgia , Humanos
6.
J Ultrasound Med ; 37(8): 2043-2052, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29399851

RESUMO

OBJECTIVES: The aim of the study was to assess the feasibility of ultrasound strain imaging in characterizing the biceps brachii muscle in chronic poststroke spasticity. METHODS: We prospectively analyzed strain imaging data from bilateral biceps brachii muscles in 8 healthy volunteers and 7 patients with poststroke chronic spasticity. Axial deformations of the biceps brachii muscle and overlying subcutaneous tissue were produced by external compression using a sandbag (1.0 kg) attached to a transducer. The lengthening and shortening of the biceps brachii muscle and subcutaneous tissue were produced by manual passive elbow extension (from 90° to 0°) and flexion (from 0° to 90°), respectively. We used offline 2-dimensional speckle tracking to estimate axial and longitudinal strain ratios (biceps brachii strain/subcutaneous tissue strain), and the longitudinal tissue velocity of the biceps brachii muscle. Statistical analyses included analysis of variance for testing differences in strain imaging parameters among healthy, nonspastic, and spastic biceps brachii muscles, the Bonferroni correction for further testing differences in US strain imaging among paired groups (healthy versus spastic, nonspastic versus spastic, and healthy versus nonspastic), and the Pearson correlation coefficient for assessing the intraobserver reliability of performing strain imaging in stroke survivors. RESULTS: The differences in strain imaging parameters between healthy and spastic and between nonspastic and spastic biceps brachii muscles were significant at both 90° elbow flexion and maximal elbow extension (P < .01). There was no significant difference in axial strain ratios at 90° of elbow flexion or longitudinal tissue velocities between healthy and nonspastic muscles (P > .05). The intraobserver reliability of performing strain imaging in stroke survivors was good (r = 0.85; P < .01). CONCLUSIONS: Ultrasound strain imaging seems to be feasible for characterizing the biceps brachii muscle in chronic poststroke spasticity.


Assuntos
Espasticidade Muscular/diagnóstico por imagem , Espasticidade Muscular/fisiopatologia , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiopatologia , Acidente Vascular Cerebral/complicações , Ultrassonografia/métodos , Adulto , Idoso , Braço/diagnóstico por imagem , Braço/fisiopatologia , Doença Crônica , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espasticidade Muscular/etiologia , Estudos Prospectivos , Amplitude de Movimento Articular , Reprodutibilidade dos Testes
7.
J Ultrasound Med ; 32(10): 1769-75, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24065258

RESUMO

OBJECTIVES: To quantitatively assess the correlation between the corticomedullary strain ratio and cortical fibrosis in renal transplants. METHODS: Using quasistatic ultrasound elasticity imaging, we prospectively assessed the corticomedullary strain ratio in renal allografts of 33 patients who underwent renal transplant sonography and biopsy. Based on Banff score criteria for renal cortical fibrosis, 33 allografts were divided into 2 groups: group 1 (n = 19), with mild (<25%) fibrosis; and group 2 (n = 14), with moderate (>26%) fibrosis. We used 2-dimensional speckle-tracking software to perform offline analysis of cortical and medullary strain induced by external compression by the ultrasound transducer. We then calculated the corticomedullary strain ratio (cortical normalized strain/medullary normalized strain; normalized strain = developed strain/applied strain [deformation from the abdominal wall to the pelvic muscles]). An unpaired 2-tailed t test was used to determine differences in normalized strain and the strain ratio between the groups. Receiver operating characteristic curve analysis was performed to determine the best strain ratio cutoff value for identifying moderate fibrosis. RESULTS: Normalized strain differed between the cortex and medulla (mean ± SD: group 1, 4.58 ± 2.02 versus 2.58 ± 1.38; P = .002; group 2, 1.71 ± 0.42 versus 2.60 ± 0.87; P = .0011). The strain ratio in group 1 was higher than in group 2 (2.06 ± 1.33 versus 0.70 ± 0.20; P = .0007). The area under the receiver operating characteristic curve was 0.964. The sensitivity and specificity of a strain ratio cutoff value of 0.975 for determining moderate fibrosis were 92.9% and 94.7%, respectively. CONCLUSIONS: Strain values vary in different compartments of the kidney. The corticomedullary strain ratio on ultrasound elasticity imaging decreases with increasing renal cortical fibrosis, which makes it potentially useful as a noninvasive quantitative marker for monitoring the progression of fibrosis in renal transplants.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Interpretação de Imagem Assistida por Computador/métodos , Córtex Renal/patologia , Córtex Renal/fisiopatologia , Medula Renal/patologia , Medula Renal/fisiopatologia , Transplante de Rim/efeitos adversos , Injúria Renal Aguda , Adulto , Idoso , Biomarcadores , Módulo de Elasticidade , Feminino , Fibrose , Humanos , Córtex Renal/diagnóstico por imagem , Medula Renal/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Terapêutica , Resultado do Tratamento , Adulto Jovem
8.
J Ultrasound Med ; 32(2): 221-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23341376

RESUMO

OBJECTIVES: To prospectively assess changes in spleen stiffness and splenoportal venous flow before and after transjugular intrahepatic portosystemic shunt (TIPS) placement. METHODS: We prospectively evaluated spleen stiffness measured by the mean shear wave velocity with acoustic radiation force impulse imaging and the splenoportal venous velocity with color Doppler sonography in 12 patients (mean age ± SD, 42.6 ± 11.0 years; range, 29-65 years) who underwent TIPS placement for portal hypertension and gastroesophageal bleeding. The mean shear wave velocity and angle-corrected splenoportal venous velocity at the main portal and splenic veins were measured 1 day before and 3 to 9 days after TIPS placement (mean interval, 6.0 ± 1.95 days; range, 4-10 days) and were compared with portal vein pressure measured during the procedure. RESULTS: There was a significant difference in portal vein pressure before and after TIPS (25.34 ± 6.21 versus 15.66 ± 6.07 mm Hg; P = .0005). After TIPS, the mean shear wave velocity decreased significantly in all 12 cases (3.50 ± 0.46 versus 3.15 ± 0.39 m/s before and after TIPS; P = .00015). The flow velocity at the main portal vein increased significantly after TIPS (22.21 ± 4.13 versus 47.25 ± 12.37 cm/s; P = .0000051). The splenic vein velocity and spleen index measured 25.57 ± 6.98 cm/s and 55.99 ± 21.27 cm(2), respectively, before TIPS and 35.72 ± 11.10 cm/s and 50.11 ± 21.12 cm(2) after TIPS (P = .0004 and .003). CONCLUSIONS: A significant decrease in the mean shear wave velocity and increase in the splenoportal venous velocity occurred with reduced portal vein pressure after TIPS placement. Hence, both parameters can be used as noninvasive quantitative markers for monitoring TIPS function after placement.


Assuntos
Hipertensão Portal/diagnóstico por imagem , Hipertensão Portal/cirurgia , Veia Porta/diagnóstico por imagem , Derivação Portossistêmica Transjugular Intra-Hepática , Baço/diagnóstico por imagem , Adulto , Idoso , Velocidade do Fluxo Sanguíneo , Elasticidade , Técnicas de Imagem por Elasticidade , Feminino , Humanos , Hipertensão Portal/fisiopatologia , Masculino , Pessoa de Meia-Idade , Pressão na Veia Porta , Veia Porta/fisiopatologia , Derivação Portossistêmica Transjugular Intra-Hepática/instrumentação , Cuidados Pós-Operatórios , Cuidados Pré-Operatórios , Estudos Prospectivos , Análise de Onda de Pulso , Fluxo Sanguíneo Regional , Baço/fisiopatologia , Stents , Ultrassonografia Doppler em Cores
9.
Clin Imaging ; 78: 22-34, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33721575

RESUMO

This review summarizes the current state of non-invasive diagnosis of non-alcoholic fatty liver disease (NAFLD). This begins with a brief discussion of blood-based analysis (serum biomarkers) then progresses through various imaging modalities (imaging biomarkers) including magnetic resonance (MR), computed tomography (CT), and ultrasound-based imaging methods. The review concludes with comment on the advantages, disadvantages, and prospects of commercially available modalities and the impact they may have on diagnosis and management of patients with NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Biomarcadores , Humanos , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Ultrassonografia
10.
Ultrasound Med Biol ; 45(5): 1094-1102, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30898386

RESUMO

The aim of the study was to evaluate the feasibility of using ultrasound elastography to assess the effect of botulinum toxin A (BoNT-A) treatment on post-stroke spasticity of the upper limb. In this prospective study, we performed ultrasound elastography (strain imaging and acoustic radiation force impulse-based shear wave elastography) of the spastic biceps brachii muscle in seven patients (five men and two women, mean age: 45y) who underwent BoNT-A injection treatment for post-stroke spasticity of the upper limb. We measured ultrasound elasticity parameters including axial strain ratio (SR) (SR = muscle strain/reference strain), longitudinal SR and shear wave velocity of the biceps muscle immediately before and 17-30 d (mean: 22 d) after BoNT-A injection. Statistical analyses included a two-tailed paired t-test to examine the difference in ultrasound elasticity parameters of bilateral biceps muscles before and after BoNT-A treatment and a Spearman rank correlation coefficient (rs) to analyze the correlation of ultrasound elasticity parameters to clinical assessment with the Modified Ashworth Scale (MAS) and Tardieu Scale (TS). The difference in ultrasound elasticity parameters before and after BoNT-A treatment was significant (p < 0.05) in the treated spastic muscle. The correlation of ultrasound elasticity parameters with MAS and the angle of catch and range of motion in TS were also significant (rs = 0.55-0.95, p < 0.05). Our results suggest that ultrasound elastography is feasible in assessment of the effectiveness of BoNT-A treatment for post-stroke spasticity of the upper limb.


Assuntos
Toxinas Botulínicas Tipo A/uso terapêutico , Técnicas de Imagem por Elasticidade/métodos , Espasticidade Muscular/tratamento farmacológico , Fármacos Neuromusculares/uso terapêutico , Acidente Vascular Cerebral/complicações , Adulto , Idoso , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Espasticidade Muscular/diagnóstico por imagem , Espasticidade Muscular/etiologia , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/efeitos dos fármacos , Estudos Prospectivos , Resultado do Tratamento
11.
Ultrasound Med Biol ; 44(9): 1931-1940, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29398131

RESUMO

We prospectively investigated the feasibility of using quantitative ultrasound imaging (QUI) to assess the biceps brachii muscle (BBM) in individuals with chronic post-stroke spasticity. To quantify muscle echogenicity and stiffness, we measured QUI parameters (gray-scale pixel value and shear wave velocity [SWV, m/s]) of the BBM in three groups: 16 healthy BBMs; 12 post-stroke, non-spastic BBMs; and 12 post-stroke, spastic BBMs. The QUI results were compared with the Modified Ashworth Scale and Tardieu Scale. A total of 20 SWVs were measured in each BBM, once at elbow in 90° flexion and again at maximally achievable extension using acoustic radiation force impulse imaging. BBM pixel value was measured in gray-scale images captured at 90° elbow flexion using ImageJ software. Statistical analyses included analysis of variance for examining the difference in SWV and pixel values among the three groups; Bonferroni correction for testing the difference in SWV and pixel values in a paired group; t-test for examining the difference in SWV values measured at two elbow angles; and Pearson correlation coefficient for analyzing the correlation of QUI to Modified Ashworth Scale and Tardieu Scale. SWV significantly differed between spastic BBMs and non-spastic or healthy BBMs. For pixel values, each of the three groups significantly differed from the others at elbow 90° flexion. The difference in SWV measured between the two elbow angles was also significant (p <0.01). A strong negative correlation was found between SWV and passive range of motion (R2 = -0.88, p <0.0001) in spastic upper limbs. These results suggest that the use of QUI is feasible in quantitative assessment of spastic BBM.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Espasticidade Muscular/diagnóstico por imagem , Espasticidade Muscular/fisiopatologia , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/fisiopatologia , Extremidade Superior/diagnóstico por imagem , Adulto , Idoso , Doença Crônica , Estudos de Avaliação como Assunto , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/diagnóstico por imagem , Estudos Prospectivos , Amplitude de Movimento Articular , Reprodutibilidade dos Testes , Ultrassonografia , Extremidade Superior/fisiopatologia
12.
Inflamm Bowel Dis ; 29(9): 1499-1503, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36421052

RESUMO

Higher ustekinumab concentrations were associated with improved radiologic (Simplified Magnetic Resonance Index of Activity for Crohn's Disease) and stringent biomarker (calprotectin) outcomes. The high concentration needed for these novel endpoints validates previous studies using the same assay.


Assuntos
Doença de Crohn , Ustekinumab , Humanos , Ustekinumab/uso terapêutico , Doença de Crohn/tratamento farmacológico , Anticorpos Monoclonais , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Resultado do Tratamento , Indução de Remissão
13.
Clin Cancer Res ; 12(19): 5770-6, 2006 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-17020983

RESUMO

PURPOSE: Drug resistance in brain tumors is partially mediated by the blood-brain barrier of which a key component is P-glycoprotein, which is highly expressed in cerebral capillaries. Tamoxifen is a nontoxic inhibitor of P-glycoprotein. This trial assessed, in primary and metastatic brain tumors, the differential deposition of paclitaxel and whether tamoxifen could increase paclitaxel deposition. EXPERIMENTAL DESIGN: Patients for surgical resection of their primary or metastatic brain tumors were prospectively randomized to prior paclitaxel alone (175 mg/m(2)/i.v.) or tamoxifen for 5 days followed by paclitaxel. Central and peripheral tumor, surrounding normal brain and plasma, were analyzed for paclitaxel and tamoxifen. RESULTS: Twenty-seven patients completed the study. Based on a multivariate linear regression model, no significant differences in paclitaxel concentrations between the two study arms were found after adjusting for treatment group (tamoxifen versus control). However, in analysis for tumor type, metastatic brain tumors had higher paclitaxel concentrations in the tumor center (1.93-fold, P = 0.10) and in the tumor periphery (2.46-fold, P = 0.039) compared with primary brain tumors. Pharmacokinetic analyses showed comparable paclitaxel areas under the serum concentration between treatment arms. CONCLUSIONS: Paclitaxel deposition was not increased with this tamoxifen schedule as the low plasma concentrations were likely secondary to concurrent use of P-450-inducing medications. However, the statistically higher paclitaxel deposition in the periphery of metastatic brain tumors provides functional evidence corroborating reports of decreased P-glycoprotein expression in metastatic versus primary brain tumors. This suggests that metastatic brain tumors may respond to paclitaxel if it has proven clinical efficacy for the primary tumor's histopathology.


Assuntos
Antineoplásicos Hormonais/farmacocinética , Antineoplásicos Fitogênicos/farmacocinética , Neoplasias Encefálicas/sangue , Paclitaxel/farmacocinética , Tamoxifeno/farmacocinética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/patologia , Sinergismo Farmacológico , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
14.
Clin Imaging ; 45: 26-29, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28586712

RESUMO

OBJECTIVE: To assess differences in biceps brachii muscle (BBM) stiffness as evaluated by ultrasound shear wave elastography (SWE). METHODS: The passive stiffness of the BBM was quantified with shear wave velocity (SWV) measurements obtained from 10 healthy volunteers (5 men and 5 women, mean age 50years, age range 42-63 years) with the elbow at full extension and 30° flexion in this IRB-approved study. Potential differences between two depths within the muscle, two elbow positions, the two arms, and sexes were assessed by using two-tailed t-test. The reproducibility of SWV measurements was tested by using intraclass correlation coefficient (ICC). RESULTS: Significantly higher passive BBM stiffness was found at full elbow extension compared to 30° of flexion (p≤0.00006 for both arms). Significantly higher passive stiffness in women was seen for the right arm (p=0.04 for both elbow positions). Good correlation of shear wave velocity measured at the different depths. The ICC for interobserver and intraobserver variation was high. CONCLUSIONS: SWE is a reliable quantitative tool for assessing BBM stiffness, with differences in stiffness based on elbow position demonstrated and based on sex suggested.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Articulação do Cotovelo/diagnóstico por imagem , Cotovelo/diagnóstico por imagem , Músculo Esquelético/diagnóstico por imagem , Amplitude de Movimento Articular , Adulto , Técnicas de Imagem por Elasticidade/normas , Cotovelo/patologia , Articulação do Cotovelo/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Fatores Sexuais , Ultrassonografia/métodos
15.
Ultrasound Med Biol ; 43(8): 1729-1736, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28549736

RESUMO

We prospectively evaluated the feasibility of using ultrasound strain imaging (USI) to assess biceps brachii muscle (BBM) stiffness and dynamic motion in 10 healthy adults. The BBM axial deformation was produced by external compression with a sandbag (1.0 kg) tied onto the transducer. The BBM lateral movement was produced by manual passive elbow flexion and extension. By use of 2-D speckle tracking, captured 5-s real-time ultrasound data of BBM were processed to estimate axial strain, representing muscle stiffness, and lateral strain and tissue velocity, representing muscle dynamic motion. Axial (lateral) strain ratio was defined as BBM strain divided by subcutaneous soft tissue strain. There was no significant difference in lateral strain or tissue velocity between the left and right BBM (lateral strain ratio: 4.69 ± 0.07 vs. 4.51 ± 0.08 for extension, 4.82 ± 0.09 vs. 4.69 ± 0.11 for flexion; tissue velocity: 1.58 ± 0.32 cm/s vs. 1.78 ± 0.85 cm/s for extension, -2.03 ± 0.63 vs. -2.03 ± 0.59 for flexion; all p values > 0.05) or between men and women (lateral strain ratio: 4.52 ± 0.06 vs. 4.67 ± 0.1 for extension, 4.71 ± 0.11 vs. 4.83 ± 0.09 for flexion; tissue velocity, cm/s: 1.76 ± 0.76 vs. 1.66 ± 0.65 for extension, -2.21 ± 0.65 vs. -1.88 ± 0.52 for flexion, all p values > 0.05). The difference in axial stain between men and women was significant (axial strain ratio: 3.09 ± 0.43 vs. 3.52 ± 0.26, p = 0.02). Inter- and intra-observer reliability in performing USI of the BBM was good (all intra-class correlation coefficients [ICCs] >0.75). Our results suggest that USI seems to be feasible for and reproducible in estimating BBM mechanical properties and motion dynamics in healthy adults.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiologia , Amplitude de Movimento Articular/fisiologia , Ultrassonografia/métodos , Adulto , Braço/diagnóstico por imagem , Braço/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Valores de Referência , Reprodutibilidade dos Testes
17.
JSLS ; 6(4): 345-7, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12500834

RESUMO

OBJECTIVES: Low anterior resection with hand-sutured coloanal anastomosis for low rectal cancer is technically feasible, and it does not compromise oncologic results. We describe herein the effectiveness of the operation in treating low rectal cancer by a laparoscopic approach followed by intraanal canal dissection. METHODS: From February 1999 to October 1999, we used a laparoscopic procedure to divide the inferior mesenteric vessels and to dissect downward into the pelvic cavity as low as possible. A purse-string suture 1-cm distal to the lower margin of the tumor was secured and transection of the rectum was performed circumferentially via the anal canal near the dentate line. The specimen was removed by the pull-through method and coloanal anastomosis was completed with hand suture. A protective loop ileostomy was fashioned. RESULTS: We operated on 8 patients (4 males) with low tumor localization (average 4-cm above the dentate line). The age ranged from 45 to 83 years, with a median age of 64. The average operation time was 210 minutes (150 to 360 minutes), and the average blood loss was 250 cc (minimal to 750 cc). No operative mortalities occurred, but 2 patients had minor anastomotic slough complications. The average hospital stay was 13 days (7 to 26 days). The postoperative pathologic stage was T2N0M0 in 4 patients, T3N0M0 in 2 patients, T2N1M0 in 1 patient, and T3N2M0 in 1 patient. No local recurrence or distant metastasis occurred during the median 14 months (12 to 20 months) of follow-up. CONCLUSION: Laparoscopic coloanal anastomosis combined with intraanal canal dissection is safe and technically feasible. The oncologic results seem not to be compromised, but need further evaluation.


Assuntos
Adenocarcinoma/cirurgia , Laparoscopia/métodos , Neoplasias Retais/cirurgia , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Retais/patologia , Técnicas de Sutura
19.
Clin Imaging ; 37(5): 811-20, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23830542

RESUMO

To assess fly through ultrasound imaging (FTUS) in evaluation of carotid artery atherosclerosis, we prospectively performed conventional sonography and FTUS of the carotid artery on 66 patients with suspicion for atherosclerosis. Characteristics of arterial intima, atherosclerotic plaque, luminal narrowing, and carotid stent graft displayed on FTUS were compared with that on conventional sonography. On FTUS, normal carotid artery wall was smooth in appearance, mild carotid atherosclerosis appeared focal arterial wall irregularity and small plaque formation, arterial luminal reduction resulted from progressive artery plaques, and carotid stent had irregular inner lumen and tight fit against the arterial wall. A total of 38 plaques were detected by conventional sonography, while 48 plaques were depicted by FTUS in 25 patients. Using magnetic resonance angiography as a reference standard, 17 cases with >50% and 3 cases with <50% luminal reduction measured on FTUS. However, all those 20 cases were measured with >50% luminal reduction on conventional sonography. Compared with conventional sonography, FTUS can dynamically display intraluminal structure on real-time three-dimensional imaging morphologically to improve the accuracy in detecting atherosclerotic plaque and assessing luminal narrowing in the carotid artery.


Assuntos
Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/diagnóstico por imagem , Adulto , Idoso , Artéria Carótida Primitiva/diagnóstico por imagem , Feminino , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Ultrassonografia/métodos
20.
Cancer ; 112(5): 1139-46, 2008 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-18246536

RESUMO

BACKGROUND: The prognosis for patients with recurrent high-grade gliomas is poor and treatment options are limited. Current chemotherapeutic regimens can improve clinical outcomes, but extend survival by only a few months. Temozolomide is a methylating agent that is typically administered once daily. Because preclinical studies suggested that a twice-daily dosing schedule might be more effective, the safety and efficacy of twice-daily dosing of temozolomide were studied in patients with recurrent gliomas at their first, second, or third recurrence. METHODS: This multi-institutional trial enrolled 120 patients with recurrent glioblastoma multiforme (GBM), anaplastic astrocytoma (AA), or anaplastic oligodendroglioma (AO). An initial oral dose of 200 mg/m(2) of temozolomide was followed by 9 consecutive doses of 90-mg/m(2) every 12 hours. Treatment cycles were repeated every 28 days. Doses were escalated to 100 mg/m(2) twice daily in the absence of unacceptable toxicity or were reduced if unacceptable toxicity occurred. RESULTS: For GBM, AA, and AO patients, respectively, the median progression-free survival (PFS) was 4.2 months, 5.8 months, and 7.7 months, whereas the median overall survival (OS) was 8.8 months, 14.6 months, and 18 months. The overall response rate (partial and complete) for the GBM, AA, and AO patients was 31%, 46%, and 46%, respectively. Grade 3/4 toxicities included neutropenia (1.1%), thrombocytopenia (3.6%), and anemia (0.3%) (graded according to the World Health Organization grading system). CONCLUSIONS: Twice-daily dosing may enhance the efficacy of temozolomide in the treatment of recurrent gliomas without increasing toxicity. This regimen compares favorably with other dosing schedules of temozolomide reported in the literature.


Assuntos
Antineoplásicos Alquilantes/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Dacarbazina/análogos & derivados , Glioma/tratamento farmacológico , Administração Oral , Adulto , Idoso , Antineoplásicos Alquilantes/toxicidade , Dacarbazina/administração & dosagem , Dacarbazina/toxicidade , Esquema de Medicação , Avaliação de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Temozolomida
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